JP2019087251A - Abnormal water level notification system - Google Patents

Abstract

To provide an abnormal water level notification system at a low maintenance cost and a low system introduction cost, which can highly reliably detect an abnormal water level.SOLUTION: An abnormal water level notification system is provided with a center node 2, a router node 3 and a leaf node 4. The leaf node 4 of an RF device such as an RF tag wirelessly transmits a leaf response signal to the router node 3, the router node 3 detects the leaf node 4 to which transmission of the leaf response signal is discontinued, and detects generation of an abnormal water level and flood depth. Information detected at the router node 3 is wirelessly transmitted to the center node 2 with router position information as water level detection information, the center node 2 provides an abnormality notification on the basis of the received information, and transmits the received information to a flood disaster information collection and distribution server 1 on cloud environment 6 via a channel. The flood disaster information collection and distribution server 1 generates a flood disaster generation map on the basis of the received information to be collected, and distributes the generated flood disaster generation map to each portable terminal 5.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an abnormal water level notification system that reports occurrence of an abnormal water level caused by heavy rain and urges residents to evacuate.

  In recent years, the occurrence of abnormal heavy rains such as heavy rain and guerrilla heavy rain has increased, and the damage caused by floods and debris flows also tends to increase. At the time of abnormal heavy rainfall, the Meteorological Agency, the Ministry of Land, Infrastructure, Transport and Tourism, and relevant organizations of the prefectural government evacuate the residents in the area at risk of flooding based on the results of river level and discharge observation at predetermined points. An advisory and evacuation order has been issued to reduce human damage. Thus, conventionally, the thing of patent documents 1-3 is known as a technique relevant to the system which warns a resident about the danger of a flood.

  Patent Document 1 is an abnormal water level alarm device that warns of an abnormal water level for a passing vehicle on a bridge such as a river or lake, and is an interrogator capable of transmitting a microwave inquiry signal and receiving a response signal. An abnormal water level equipped with a transponder installed at the water surface position to be detected and returning a microwave response signal when the interrogator's interrogation signal is received, and a determination unit that determines the water level based on the presence or absence of the interrogator response signal An alarm device is described (Patent Document 1 and Claim 1). This abnormal water level alarm device is a water level detection device that transmits and receives data using microwaves by utilizing the property that microwaves are absorbed by water (仝 [0011]). The interrogator and transponder operate with built-in batteries and are installed near the water surface to be detected. The responders are normally not flooded but are placed at flooded locations (see Figures 8 and 9 in the literature). When the transponder is not submerged, the transponder receives the interrogation signal transmitted by the interrogator, and the transponder returns a response signal corresponding to the stored data. Therefore, the interrogator can receive the response signal, and the determination unit determines that the water level is not abnormal. When the water level rises and the transponder is submerged, the microwave interrogation signal transmitted by the interrogator is absorbed by the water and can not be received by the transponder, and the response signal is not returned to the interrogator. Thus, the determination unit determines that the water level is not abnormal (仝 [0022]-[0025]).

  The river water level warning unit described in Patent Document 2 measures the river water level by a water level measurement sensor (FIG. 2 of Patent Document 2) installed on a bridge or the like, compares the measured water level with the water level determination standard, An alarm is issued by a rotary whistle, a buzzer, a message output, etc., provided in the unit according to each condition such as rising or rapid water increase (see paragraph [0026] in FIG. 1, FIG. 1) and a wireless communication circuit. The alarm result is sent to the central management unit via the communication unit (section [0027]).

  The flood occurrence alarm system described in Patent Document 3 includes various points corresponding to the height of the ground, the gate, the stone wall, the block fence (Patent Document 3 specification paragraph [0022], FIG. 1) of the house and the river. 4) install a flood occurrence alarm device, each flood occurrence alarm device detects the water level and issues an alarm by alarm buzzer or alarm lamp (仝 [0034]), and by the transmission means in the device , Sends a flood alert to the alert management center (仝 [0038]). Here, the flood occurrence alarming device comprises a main circuit portion provided with a float switch for detecting water, and a sub-circuit portion provided with alarm means (alarm buzzer and alarm lamp) for emitting an alarm, and the main circuit portion The relay is electrically connected in series to the float switch, the first set relay electrically connected in parallel to the float switch, and the auxiliary circuit electrically connected in series to the alarm means. The second set relay is disposed on the When the float switch detects water and turns on, the actuating relay is energized to energize the first and second set relays, and the first set relay is energized to hold the actuating relay in the energized state. The second set relay is energized to activate the alarm means (仝 [0028]-[0034]). Thus, it is devised to detect the occurrence of a flood for a long time while minimizing the consumption of electric power (電力 [0019]).

JP, 2000-298055, A Unexamined-Japanese-Patent No. 2010-170190 JP, 2013-109558, A

Edited by Japan Association of Automatic Identification Systems, "Good RFID", Rev. 2 Edition, Japan, OHM Corporation, June 20, 2014.

  The river level warning unit of Patent Document 2 is mounted on a bridge and measures the height from the bridge to the water surface of the river with a water level measurement sensor, and therefore, is basically mounted on the river. However, in recent floods, it is not uncommon for water to overflow from culverts and waterways and make evacuation difficult, and the river water level warning unit of Patent Document 2 warns nearby residents of floods about the danger of flooding. It is not enough to apply as a system to issue an alert.

  On the other hand, in the flood occurrence alarm system of Patent Document 3, an alarm device is provided inside a house such as a house (see FIG. 1 of Patent Document 3), and a float type water level detection switch installed on the side of a house or on a river bank. An abnormal water level is detected and an alarm is issued. Therefore, even when the road overflows from a culvert or a canal other than a river, an abnormal water level can be detected and an alarm can be issued. However, since the float type water level detection switch is prone to malfunction due to garbage clogs and clogs such as ant, moth, and mud bee if maintenance is not performed for a long period of time, reliability concerning operation guarantee And there are problems in terms of maintenance costs.

  In the flood alarm system of Patent Document 3 (see FIG. 4), when an abnormal water level is detected by the water level detection switch of each flood alarm device (106), an alarm buzzer or an alarm attached to the flood alarm device An alarm is issued by a lamp, and a flood occurrence alarm device transmits a flood occurrence signal to a high alarm management center by wireless or wired (仝 [0038], [0041]), and an alarm or warning is issued from the alarm management center. Flood warning information and flood warning information are issued by alarm output means (152) such as loudspeakers installed in various places (仝 [0042]). However, introducing such a large-scale system requires a large amount of equipment cost, and it is difficult to introduce this system in a financially weak municipality. In recent years, flood damage caused by heavy rainfall often occurs in mountainous areas where the population density is low, and it is not realistic to introduce equipment such as an alarm management center in each of the mountainous areas. In heavy rains, many cases where sound from alarm output means such as a loudspeaker does not reach surrounding residents due to rain noise have been reported so far, even in terms of evacuability of evacuation information. There's a problem.

  In addition, with regard to the reliability and maintenance cost concerning the operation guarantee of the water level sensor mentioned in the problem in the above-mentioned Patent Document 3, the water level sensor using the interrogator and the transponder by the microwave described in Patent Document 1 is applied. It is conceivable. However, even in this case, there still remain problems regarding the system introduction cost problem, the application difficult problem in the mountainous area, and the issue of the evacuation information transferability.

  Therefore, the object of the present invention is high reliability regarding abnormal water level detection and capable of suppressing maintenance cost, low introduction cost of the system, and easy introduction easily in non-administrative general households and small business establishments It is to provide an abnormal water level notification system that can be

  In addition, another object of the present invention is to provide an abnormal water level notification system capable of reliably transmitting evacuation information to residents even during heavy rain, and providing information for appropriate evacuation determination. It is to do.

The first configuration of the abnormal water level notification system according to the present invention is an abnormal water level notification system that detects and reports occurrence of an abnormal water level due to rainfall,
A center node installed indoors in the building;
One or more router nodes installed indoors or outdoors around the center node;
One or more leaf nodes installed in the vicinity of each of the router nodes;
The router node is
Router node position output means for detecting router position information representing the self position by the global positioning satellite system, or outputting router position information representing the self position prerecorded in the position information storage means;
Response receiving means for receiving a leaf response signal transmitted from each leaf node in response to an interrogation signal wirelessly transmitted to the surrounding space with respect to each leaf node, or intermittently at predetermined time intervals;
Based on the presence or absence of transmission of the leaf response signal among the leaf nodes, or based on the intensity change of the leaf response signal, the presence or absence of water approaching or inundation is determined, and it is determined that there is water approaching or inundation. A water level detection unit that generates water level detection information in which a value indicating water level detection is validated when it is determined;
Water level detection signal transmission means for wirelessly transmitting the water level detection information output by the water level detection means to the center node together with the router position information;
The leaf node is
Leaf ID storage means for storing a leaf ID which is an identification code of the leaf node;
When the inquiry signal transmitted from the router node is received, or intermittently at predetermined time intervals, the leaf response signal including the leaf ID stored in the leaf ID storage means is generated and wirelessly transmitted to the surrounding space Providing a leaf node response means to transmit;
The center node is
A communication interface that communicates with the outside via a public communication line;
Center node receiving means for receiving the water level detection information and the router position information wirelessly transmitted from the router node;
When the center node reception means receives the water level detection information and the router position information, when the value indicating the water level detection of the water level detection information is valid, the occurrence of the abnormal water level is notified to the surroundings by voice or display. 1 anomaly notification means,
When the center node reception means receives the water level detection information and the router position information, if the value indicating the water level detection of the water level detection information is valid, the water level detection information and the router position information And an abnormal water level information transmission means for transmitting information to an external flood damage information collection and distribution server via a line.

  According to this configuration, when introducing an abnormal water level detection system in each household, each household may introduce only the center node independently. Since the router node and leaf node are shared by each center node, the local government can bear and install it as a shared burden or public facilities of the household that introduced the abnormal water level detection system, and it is introduced as a whole. Cost can be reduced. Also, in this system, each router node transmits detection information of abnormal water level, and the center node is notified of occurrence of abnormality by voice or display in the building based on the detection information of abnormal water level transmitted by each router node. Ru. Therefore, it is not necessary to introduce facilities, such as a high-level alarm management center like patent document 3, to each place, for example, and each household and each office can introduce a system easily independently. Therefore, it can be applied to mountainous areas where the population density is low and scattered in various places. In addition, the detection of the abnormal water level determines the approach of water by the electromagnetic wave change transmitted by the leaf node, and the presence or absence of water immersion. Therefore, compared with the float type water level detection switch, the mechanical mechanism is not used and the reliability of the detector Are easy to install and maintain. In addition, since RFID or Bluetooth (registered trademark) beacons can be used for leaf nodes, they are inexpensive, and if a large number of leaf nodes are installed around a router node, detection accuracy can be increased any number of times. Further, the detection of the abnormal water level is performed depending on whether or not the leaf node in the vicinity of each router node is submerged, and the router node is suitable for wireless communication and can be installed at a high place where the risk of being submerged is small. As a result, it is possible to extend the distance in which the wireless communication between the router node and the center node is possible, and it is possible to detect the abnormal water level in a wide range centering on the center node. Also, even after the area around the router node is flooded, the router node can continuously transmit the detection information of the abnormal water level unless the router node is submerged. Therefore, by setting a plurality of leaf nodes in the vicinity of the router node with different heights, it is possible to detect the inundation depth in the vicinity of the router node. Further, since each router node is provided with a router node position output means, the position can be grasped by the center node and the flood information collection and distribution server side only by installing the router node. Therefore, when installing a router node, it is not necessary to set its position on the flood damage information collection and distribution server side, and it is possible to easily add a router node.

  Here, "Global Navigation Satellite System (GNSS)" is a generic term for satellite positioning systems such as GPS (Global Positioning System), GLONASS, Galileo, and Quasi-Zenith Satellite (QZSS). The “self position recorded in advance in the position information storage means” refers to the position of the router node written and recorded in the position information storage means such as a rewritable memory built in the router node when the router node is installed. Refers to location information. The “leaf response signal transmitted from each leaf node with respect to the interrogation signal wirelessly transmitted to the surrounding space with respect to each leaf node or intermittently at a predetermined time interval” means “leaf in leaf node When the router node transmits a leaf response signal from each leaf node in response to an interrogation signal wirelessly transmitted to the surrounding space to each leaf node as a transmission method of “response signal” (question response system), and depending on the interrogation signal Also, it means that each leaf node intermittently transmits a leaf response signal at a predetermined time interval (push method). Here, the “predetermined time interval” includes not only a fixed time interval, but also a random time which is sequentially determined by random numbers at intervals of 5 to 10 minutes at leaf nodes, for example (Example 1, See Figure 10).

A second configuration of the abnormal water level notification system according to the present invention is, in the first configuration, a plurality of the center nodes arranged in buildings at various places;
A flood information collection and delivery server connected to the center node via a public communication line;
The flood damage information collection delivery server is
Flood damage map database which manages flood occurrence transaction information which is transaction information for displaying occurrence information of abnormal water level on the map,
Server side receiving means for receiving the water level detection information and the router position information transmitted from each of the center nodes;
Map information acquisition means for acquiring map information from a map distribution server via a public communication line or from a map database provided in the flood damage information collection distribution server;
A flood occurrence map generation unit that generates the flood occurrence transaction information based on the received water level detection information, the router position information, and the map information and stores the flood occurrence transaction information in the flood map database;
In accordance with a map distribution request and position information transmitted from the outside via a public communication line, map information of a predetermined range centered on a designated position designated by the position information by the map information acquisition means (hereinafter referred to as “ "Designated location surrounding map information" is displayed and flood occurrence information is displayed in the designated location surrounding map information based on the flood occurrence transaction information related to the designated location surrounding map information extracted from the flood damage map database Map distribution means for generating the generated flood damage map information and distributing the flood damage map information;
It is characterized by having.

  With this configuration, the flood information collection distribution server collects water level detection information transmitted from the router nodes installed in various places via the center node, and distributes the flood occurrence map information, whereby Residents or residents, and related organizations such as local governments that have jurisdiction over the area can easily and accurately grasp the occurrence of floods in real time. And since the resident or resident of the area where the flood has occurred can know the occurrence situation of the flood without passing the administration, it can carry out the prompt and appropriate voluntary evacuation.

In a third configuration of the abnormal water level notification system according to the present invention, in the second configuration, a plurality of leaf nodes are installed at different heights in the vicinity of each of the router nodes, The leaf ID storing means of each leaf node stores the leaf ID including height information assigned according to each height;
The router node comprises leaf list storage means for generating and storing a list of leaf IDs included in the leaf response signal normally received at the router node,
The water level detection means of the router node extracts the leaf ID of the leaf node for which the reply of the leaf response signal is interrupted with respect to the inquiry signal among the leaf IDs stored in the leaf list storage means Generating the water level detection information including the height information included in the extracted leaf ID;
The flood occurrence map generation means of the flood information collection and delivery server is based on the water level detection information including the received water level information, the router position information, and the map information, the occurrence position of the abnormal water level and the occurrence position thereof. It is characterized in that it generates flood damage map information indicating the water level on a map.

  With this configuration, for example, when the water level becomes very high due to a flood and the router node itself is submerged, or when the router node itself is submerged or washed away due to the occurrence of a rapid rise in water level such as in the case of debris flow or levee break. Also, the abnormal water level at the installation point of the router node can be accurately detected.

  In a fourth configuration of the abnormal water level notification system according to the present invention, in the second or third configuration, the flood occurrence map generation unit indicates the router location information based on the received router location information. The elevation data around the position is acquired from the map information, the inundation estimation range around the position indicated by the position information is extracted based on the acquired elevation data, and the occurrence position of the abnormal water level and the inundation estimation range The flood damage map information shown on a map is generated.

  With this configuration, when a resident or resident in a region where inundation has occurred evacuates, the occurrence position of the abnormal water level and the inundation estimation range can be grasped on the map, and it is judged whether to evacuate or stay, It becomes possible to accurately determine which evacuation route to evacuate.

  In a fifth configuration of the abnormal water level notification system according to the present invention, in the second or third configuration, the flood occurrence map generation unit indicates the router position information based on the received router position information. The elevation data around the position and the route information of the road are acquired from the map information, the inundation estimation range around the position indicated by the position information is extracted, and the inundation estimation road range which is a road range included in the inundation estimation range To generate the flood occurrence map information in which the occurrence position of the abnormal water level and the estimated inundation estimated road range are indicated on a map.

  With this configuration, when a resident or resident in a region where flooding has occurred evacuates, the occurrence position of the abnormal water level and the estimated inundation road range can be grasped on the map, and it is judged whether evacuation or stay should be It is possible to accurately determine which evacuation route to evacuate.

According to a sixth configuration of the abnormal water level notification system of the present invention, in any one of the second to fifth configurations, a portable terminal device connected to the flood damage information collection and distribution server via a public communication line is provided. Equipped
The portable terminal device is
A display,
Mobile terminal position detection means for detecting position information representing self position by a global positioning satellite system;
Map distribution request means for transmitting the map distribution request to the flood damage information collection distribution server via a public communication line together with the position information detected by the portable terminal position detection means;
Map receiving means for receiving the flood occurrence map information transmitted from the flood information collection and delivery server via a public communication line in response to the map delivery request;
Map display means for displaying the flood occurrence map information received by the map reception means on the display;
It is characterized by having.

  With this configuration, by displaying the flood occurrence map information on a map with a portable terminal device, the occurrence range of the abnormal water level can be grasped on the map even while the residents or residents of the area where the inundation occurred are evacuated. It will be possible to make decisions on which evacuation route to evacuate.

According to a seventh configuration of the abnormal water level notification system of the present invention, in any one of the second to sixth configurations, each of the router nodes stores a router ID that is an identification code of the router node. ID storage means,
The water level detection signal transmission unit of each of the router nodes wirelessly transmits the water level detection information output by the water level detection unit to the center node as water level detection information together with the router position information and the router ID. ,
Each router node is a house side router node installed near the ground side or indoor side of a building where the center node is installed, and a peripheral router node installed at each place away from the building where the center node is installed. The router ID of the shop-side router node includes shop-side node identification information identifying the shop-side router node,
The first anomaly notification means of the center node is
When the center node reception means receives the water level detection information and the router ID wirelessly transmitted from the router node,
If the router ID indicates that the shopside node identification information is a peripheral router node, a warning alert is notified to the surroundings indicating that an abnormal water level has been detected around the building,
When the router ID indicates that the store side node identification information is a store side router node, an emergency evacuation alert indicating that an abnormal water level has been detected in the middle of a building is notified to the surroundings. I assume.

  With this configuration, it is possible for residents or residents in the area where the inundation has occurred to grasp how much inundation occurs in the surrounding area.

According to an eighth configuration of the abnormal water level notification system according to the present invention, in the seventh configuration, the flood damage information collection distribution server is
When the server-side receiving unit receives the water level detection information and the router position information transmitted from the center node,
Based on the map information, among the buildings in which each of the center nodes is installed, a building which is estimated to be affected by a flood with respect to a position specified by the router position information is extracted;
A flood warning information transmitting means for transmitting flood warning information via public communication lines to each of the center nodes installed in the extracted building;
The first anomaly notification means of the center node detects that an abnormal water level is detected upstream of the building when the flood warning information transmitted from the flood information collection and distribution server is received through a public communication line. It is characterized in that the flood warning shown is reported to the surroundings.

  With this configuration, it is possible for residents in the area downstream of the area where the inundation has occurred and the downstream area or residents of the downstream area to know that the flood has occurred in the upstream area, which can lead to early evacuation and alertness.

  Here, “a building estimated to be affected by floods with respect to the position specified by the router position information” means a building downstream of the position (specified position) specified by the router position information, or A building within a predetermined range around a specific location. Extraction of “the building that is presumed to be affected by flood damage to the position specified by the router position information” is a predetermined rule determined in advance (for example, an area downstream of the specific position and an elevation lower than the specific position) Of buildings within a certain distance from a specific position, selecting buildings in areas where water damage is estimated by hazard maps around a specific position, etc.

  A ninth configuration of the abnormal water level notification system according to the present invention is characterized in that, in any one of the first to eighth configurations, a part of the router node is a portable terminal device.

  In a tenth configuration of the abnormal water level notification system according to the present invention, in any one of the first to ninth configurations, a part or all of the router node has a value indicating the water level detection by the water level detection means. A second abnormality notification means is provided for notifying the surroundings of the occurrence of the abnormal water level by voice or display when the water level detection information is generated to be effective.

  As described above, according to the abnormal water level notification system of the present invention, it is possible for each household to directly detect the inundation in the neighborhood, so it is possible to make a decision on evacuation by itself without waiting for an evacuation advisory and an instruction. We can evacuate by helping each other. Furthermore, the introduction cost as a whole can be held down, and each household or each business establishment can easily introduce the system alone. Therefore, it can be applied not only to cities but also to mountainous areas where population density is low and scattered in various places. In addition, the abnormal water level is detected by wireless detection of the approach of water by the electromagnetic wave change of the leaf node and the presence or absence of water immersion by the router node, so no mechanical mechanism is used, dirt, foreign matter adhesion, aging deterioration The reliability of the detector is high, and the installation and maintenance are easy. Also, leaf nodes can be configured inexpensively, and a large number of leaf nodes can be installed around a router node to improve detection accuracy. Also, abnormal water level detection can be performed by installing the router node at a high place suitable for wireless communication and in which there is little risk of being submerged, and the distance that allows wireless communication between the router node and the center node can be extended. An abnormal water level can be detected in a wide range around a node. In addition, by setting the plurality of leaf nodes in the vicinity of the router node with different heights, it is possible to detect the inundation depth in the vicinity of the router node. Also, just by installing each router node, its position can be grasped by the center node and the flood information collection and distribution server side, and when installing the router node, the location is set to the flood information collection and distribution server side. There is no need, and router nodes can be easily added.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure showing the whole structure of the abnormal water level alerting | reporting system which concerns on Example 1 of this invention. FIG. 6 is a diagram showing an example of installation of a router node 3 and a leaf node 4; It is a block diagram showing the functional composition of the abnormal water level alerting system of FIG. It is a flowchart showing the initialization process of each router node. It is a flowchart showing operation | movement of detection and alerting | reporting of generation | occurrence | production of the abnormal water level in the abnormal water level alerting | reporting system of FIG. It is a flowchart showing the update process of the flood information database 17 and the flood occurrence map database 18 in the abnormal water level alerting | reporting system of FIG. It is a flowchart showing operation | movement of a delivery process of the flood occurrence map information in the abnormal water level alerting | reporting system of FIG. It is a flowchart showing operation | movement of a delivery process of the flood occurrence map information in the abnormal water level alerting | reporting system of FIG. It is a flowchart showing operation | movement of a delivery process of the flood warning in the abnormal water level alerting | reporting system of FIG. It is a flowchart showing the example at the time of applying the dispatch method of the leaf response signal by a push method to the abnormal water level alerting system of FIG. It is a figure showing the whole structure of the abnormal water level alerting | reporting system which concerns on Example 2 of this invention. It is a block diagram showing the functional composition of the abnormal water level alerting system concerning Example 3 of the present invention. FIG. 6 is a diagram showing a transmission path of a leaf response signal from leaf node 4 to router node 3; It is a figure showing the electromagnetic waves which inject into receiving point B. FIG. It is the result of calculating the relationship between the time average U _Ep ^(ave) and U _Es ^(ave) of the relative energy density of the electric field component of the electromagnetic wave received at the receiving point B and the height y _{A0 of the} water surface. It is the result of calculating the relationship between the time average U _Ep ^(ave) and U _Es ^(ave) of the relative energy density of the electric field component of the electromagnetic wave received at the receiving point B and the height y _{A0 of the} water surface. It is the result of measuring the change of the receiving intensity by the change of the distance between the transmitting point A and the water surface actually using an active beacon in the laboratory. It is a figure which shows the measurement conditions of the measurement of FIG. Intensity reflectance of water to the incident angle theta _C at a frequency f = 2.4GHz R _p, is a graph showing a change in R _s. It is a figure showing the whole structure of the abnormal water level alerting | reporting system which concerns on Example 4 of this invention. It is a block diagram showing the function structure of the abnormal water level alerting | reporting system of FIG. It is a figure showing the whole structure of the abnormal water level alerting | reporting system which concerns on Example 5 of this invention. It is a figure showing the whole structure of the abnormal water level alerting | reporting system which concerns on Example 6 of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[1] System Configuration FIG. 1 is a diagram showing the overall configuration of an abnormal water level notification system according to a first embodiment of the present invention. The abnormal water level notification system of this embodiment includes a flood information collection and distribution server 1, a center node 2, a router node 3, a leaf node 4, and a portable terminal device 5. Here, "node" means devices such as contact points, branch points, and relay points of a network.

  The flood information collection and distribution server 1 is a server that collects and distributes information on occurrence of abnormal water level transmitted from center nodes 2 installed at various places, and is a general-purpose computer such as a general personal computer or rack mount server computer. It is composed of The flood damage information collection and distribution server 1 is a management center that collects and distributes flood damage information (the installation location of the management center is not limited. It may be connected by a communication line, so it may be installed at a remote location to create a cloud virtual environment. ) And is connected to a public communication line 6 such as a fixed telephone line or a mobile telephone line. The flood information collection and distribution server 1 can connect to the Internet through the public communication line 6.

  The center node 2 receives water level detection information (information on presence / absence of detection of abnormal water level), router position information (information on position of the router node 3), and router transmitted from each router node 3 within the communicable range. A signal (hereinafter referred to as a "router signal") including an ID (identification code of the router node 3) is received, and an alarm is notified to the surroundings based on the water level detection information and the store side node identification information in the router ID. It is a node that transmits the water level detection information and the router position information to the flood damage information collection and distribution server 1. The center node 2 is installed indoors in a building B such as a house, various offices, and a river management office. The center node 2 can be connected to the public communication line 6 via a generally used LAN router and connected to the Internet. The center node 2 can also be configured by a smartphone or a personal computer (hardware) and an application (software).

Here, in the alarm notified by the center node 2 in the present embodiment, there are the following three levels as alarm levels.
(Level L1) Warning: There is a point at which an abnormal water level is detected in the area that is considered to be affected by flood damage, such as the upper basin of building B.
(Level L2) Warning alert: There is a point around building B where an abnormal water level is detected.
(Level L3) Emergency evacuation warning: Building B is approaching or submerged in water.

  In the center node 2, a warning notice or warning according to the level is notified by an alarm lamp, or a speaker makes a notification by voice or alarm sound.

  The router node 3 detects its own position information (router position information) by the Global Navigation Satellite System (GNSS) and transmits it to the center node 2, and each set in the vicinity of the router node 3. By performing near field communication with the leaf node 4 with electromagnetic waves such as microwaves, proximity of water due to electromagnetic wave change transmitted by each leaf node 4 is detected, presence or absence of water immersion is detected, and water level detection information (water approaches or flooded leaf node This node is a node that transmits information indicating that the value indicating water level detection is valid) and router location information as a router signal to the center node 2 when there are four. The router node 3 is installed indoors in the building B of each center node 2 or outdoors in the vicinity of the building B. The center node 2 and the router node 3 can communicate wirelessly within the reach of their respective radio waves (about 100 m to 10 km in this embodiment). In addition, reading of the identification code (leaf ID) of each leaf node 4 in the vicinity of the user is performed by anti-collision (multiple reading) as in the case of RFID (radio frequency identifier) widely used at present. It will be. The router node 3 can also be configured by a smartphone or an embedded computer (hard) and an application (software).

  The leaf node 4 is a node that receives an interrogation signal transmitted from the router node 3, generates a leaf response signal including the leaf ID of the leaf node 4 for wireless transmission to the surrounding space. The leaf node 4 is installed at a lower position than the router node 3 in the vicinity of each router node 3. The leaf node 4 is configured by a wireless device such as a passive RF tag, an active RF tag, and a Bluetooth (registered trademark) beacon, and one or more are installed near each router node. The router node 3 and the leaf node 4 can perform wireless communication within the reach of each radio wave (assuming several meters to 30 meters in this embodiment). The router node 4 can further extend the distance and monitor the area planarly by configuring it in a mesh shape by ad hoc communication.

  The portable terminal device 5 is a portable terminal device that displays information such as a point at which an abnormal water level occurs, a water level, a flooded road, etc. as map information. The portable terminal device 5 is used to distribute reference information of the evacuation route when the residents evacuate when the abnormal water level occurs. Since the reference information of the evacuation route is also required during evacuation, in the present system, the portable terminal device 5 that can be carried independently of the center node 2 at the time of evacuation is adopted. The mobile terminal device 5 is configured by a terminal device provided with a display such as a smartphone or a tablet and a communication function, and is connected to a public communication line 6 such as a mobile phone line. The portable terminal 5 can connect to the Internet through the public communication line 6. The portable terminal device 5 and the center node 2 can communicate with each other by near field communication such as Bluetooth (registered trademark).

  FIG. 2 is a diagram showing an example of installation of the router node 3 and the leaf node 4. As shown in FIG. 2A, the router node 3 is provided with a house side router node 3a installed near the building B side or indoor ground where the center node 2 is installed, and the center node 2 It is classified into peripheral router nodes 3 b installed at various places apart from the building B. The house router node 3a is installed on the outer wall or the inner wall of the building B or in the vicinity thereof. Also, the leaf node 4 near the house side router node 3a is installed near the ground of the foundation of the building B or a wall such as a wall near the building B at a position lower than the house side router node 3a. . In this case, since the object to which the leaf node 4 is attached is a nonmetal such as concrete, it is preferable to use a passive RFID as the leaf node 4 if the distance is about 1 m. Any number of leaf nodes 4 in the vicinity of the house router node 3a may be installed as long as they can communicate with the house router node 3a.

  On the other hand, for example, as shown in FIG. 2B, the peripheral router node 3b is attached to a structure fixed to the ground, such as a street lamp. The peripheral router node 3b is installed as high as possible so that communication with the center node 2 is possible even when flooded by heavy rain. Further, by installing the peripheral router node 3b at a high place, the communication distance with the center node 2 can be extended. The leaf node 4 installed in the vicinity of the peripheral router node 3b is configured by a passive RF tag or an active RF tag, and an RF device such as Bluetooth (registered trademark) beacon. As shown in FIG. 2 (b), the leaf node 4 is located at a position lower than the peripheral router node 3b, such as street light P, guardrail G, road sign, signal tower, pedestal box It is attached to a fixed structure such as a storage box for ground equipment. The leaf node 4 is preferably an RF device including a passive RF tag if the fixed structure attached is non-metal and the distance is about 1 m, and an RF device including an active RF tag if the metal or the distance is long is there. Also, as shown in FIG. 2 (c), for example, the peripheral router node 3b is attached to a sign on the upper side of the river embankment T of the river R, a water gate, a fixed structure such as a bridge, and the leaf node 4 is It will be fixed and installed on fixed structures such as piles or stones, piers and floodgates on the slope of the river surface of the river embankment T. In this case, since the distance between the peripheral router node 3 b and each leaf node 4 is relatively large, it is preferable to use an active RF tag as the leaf node 4.

  When a plurality of leaf nodes 4 are installed in the vicinity of the router node 3, it is preferable to install each leaf node 4 so as to have different heights, as shown in FIG. As a result, it is possible to detect the occurrence of an abnormal water level and also to detect how much the water level is at present.

  When an abnormal water level occurs and water overflows on the ground and the leaf node 4 is flooded, electromagnetic waves such as microwaves used in communication by the water around the leaf node 4 are attenuated correlated with frequency and water depth by dielectric loss of water The electromagnetic waves such as microwaves used for communication are reflected at the interface between the submerged water and the atmosphere, and the communication power is reduced in the wireless communication between the router node 3 and the leaf node 4. As a result, the error rate at the time of communication rises, and the state of communication shifts from normal to interrupted. Based on the transition of the error rate and the final interruption state, the router node 3 can detect that the leaf node 4 is flooded, and can detect the occurrence of an abnormal water level. At this time, by installing a plurality of leaf nodes 4 so as to have different heights, communication is interrupted sequentially from the leaf node 4 that is low as the water level rises, so the inundation depth at the time of occurrence of abnormal water level is The router node 3 can also detect this.

  FIG. 3 is a block diagram showing a functional configuration of the abnormal water level notification system of FIG. In FIG. 3, the same components as in FIG. 1 are denoted by the same reference numerals. The flood information collection and delivery server 1 includes a map database 10, a server side reception unit 11, a map information acquisition unit 12, a flood occurrence map generation unit 13, a map delivery unit 14, a flood warning information transmission unit 15, a line communication interface 16, and flood information. A database 17, a flood map database 18, a measurement point correction database 19, and a center node list storage unit 20 are provided. The line communication interface 16 is an interface that exchanges data with the public communication line 6. The map database 10 is a database that stores electronic map data. The flood damage information database 17 is a database for managing and storing water level detection information and router position information sent from each center node 2. Water level detection information and router position information are accumulated in the flood damage information database 17. The flood damage map database 18 is a database for managing and storing flood damage occurrence map information showing the inundation situation on the map based on the water level detection information and the router position information sent from each center node 2. The flood occurrence map information specifically takes the form of transaction data for displaying the flood occurrence information on the map. This flood occurrence map information is updated in real time every moment. The measurement point correction database 19 is a database for managing and storing information on the position correction of the router node 3. For example, in the case shown in FIGS. 2A and 2B, since the elevation at the position of the router node 3 is the same as the elevation of the leaf node 4 close to the router node 3, the position correction of the router node 3 is performed. In the case shown in Fig. 2 (c), the elevation at the location of router node 3 and the elevation of each leaf node 4 that measures the water level are significantly different. It is necessary to correct to the position of the point which becomes the standard elevation. “Information on position correction” refers to information for correcting the position of such a router node 3. In the measurement point correction database 19, position information after the correction is stored only for the router node 3 that needs to be corrected. The center node list storage unit 20 stores a list of center node related information including the identification number (center node ID), the network address on the network, and the position information of the center node 2 installed in the building B in each place. .

  The center node 2 includes a center node reception unit 21, an abnormality notification unit 22, an abnormal water level information transmission unit 23, a line communication interface 24, a long distance communication interface 25, a long distance communication antenna 26, a short distance communication interface 27, a speaker 29, an alarm A lamp 30 and a router list storage unit 31 are provided. The router list storage unit 31 stores a list of router IDs of router nodes 3 within the reception range of the center node 2 (hereinafter referred to as “router list”). The line communication interface 24 is an interface that exchanges data with the public communication line 6. The telecommunication interface 25 and the telecommunication antenna 26 are an interface and an antenna for performing wireless communication with the router node 3. It is preferable to use an interface using spread spectrum communication as the long distance communication interface 25 in order to increase the communication distance. The telecommunication antenna 26 may use an antenna provided to the center node 2 or an external antenna such as a television antenna may be connected to the center node 2 and used. The short distance communication interface 27 is an interface for performing short distance communication with the portable terminal device 5 using radio waves or infrared rays, and can use, for example, a short distance wireless communication method such as Bluetooth (registered trademark). As the alarm lamp 30, a red lamp or a rotating lamp as commonly used for a fire alarm is used.

  The router node 3 includes a position detection module 41, a router ID storage unit 42, a leaf list storage unit 43, an initialization unit 44, an initialization switch 44a, an inquiry transmission unit 45, a response reception unit 46, a water level detection unit 47, and a water level detection signal. A transmitting unit 48, a telecommunication interface 49, a telecommunication antenna 50, a short distance communication interface 51, and a short distance communication antenna 52 are provided. The position detection module 41 is a module that detects router position information indicating its own position by GNSS, and can use a generally used GPS (Global Positioning System) reception module or the like. The router ID storage unit 42 stores a router ID which is an identification code of the router node 3. The router ID includes house side node identification information for identifying the router side router node 3a or the peripheral router node 3b. For example, the code of the router ID is set as "YWWWWWW" (Y: store side node identification information, WWWWW: router number). The “shop side node identification information” is information representing classification as to whether the shop side router node 3a or the peripheral router node 3b, for example, the shop side router node 3a is Y = 0, and the periphery router node 3b is Y = 1. Set to The “router number” is an identification field number uniquely assigned to each router node 3 uniquely. The router ID can be written in the field using a wireless reader / writer at the time of installation of the router node 3 or can be set on the site only with the “house side node identification information” part using a dip switch. . For the leaf list storage unit 43, non-volatile memory such as EPROM, EEPROM, flash memory, MRAM, ReRAM, etc. is used. The telecommunications interface 49 and the telecommunications antenna 50 are an interface and an antenna that perform wireless communication with the center node 2. The short range communication interface 51 and the short range communication antenna 52 are an interface and an antenna for performing wireless communication with microwaves and the like with each leaf node 4 in the vicinity of the router node 3. The initialization switch 44 a is a push switch used when performing initialization processing of the router node 3.

  In this embodiment, an example is shown in which the "position detection module 41" for detecting router position information by GNSS is used as the "router node position output means" of the router node 3. However, in the present invention, "router node position" As the output means, instead of the position detection module 41, a “position storage memory 41 ′” that can be externally rewritten using a writer or the like may be provided. In this case, when the router node 3 is installed in the field, the location (router location information) of the installation site is measured by GNSS etc., and the router location information measured using the writer is written in advance in the location memory 41 '. Make it The position storage memory 41 'outputs the router position information written in advance in response to the request.

  The leaf node 4 includes a leaf ID storage unit 61, a leaf node reception unit 62, a leaf node response unit 63, a short distance communication interface 64, and a short distance communication antenna 65. The short range communication interface 64 and the short range communication antenna 65 are an interface and an antenna that perform wireless communication with the router node 3 in the vicinity of the leaf node 4 by microwaves or the like. The leaf ID storage unit 61 stores a leaf ID which is an identification code of the leaf node 4. The leaf ID includes height information assigned according to the height at which the leaf node 4 is installed. For example, the leaf ID code is set as "XXXXZZZZZZ" (XXXX: height information, ZZZZZZ: leaf number). The “height information” is information indicating the inundation depth of the inundation (the height from the ground surface to the water surface of the inundation area) of the point, and, for example, “0 to 0.5 m (in Subfloor inundation (adults to knees of adult)), "0.5 to 1.0 m (infloor immersion (adjacent to adult waist))", "1.0 to 2.0 m (submersible to eaves on the first floor)", "2.0 to 5.0 You may decide at stages such as m (is flooded to the eaves floor of the second floor), "5.0m ... (the floor more than the second floor is flooded)", and you decide the inundation depth divided more in detail uniquely It is also good. A numerical code is assigned to each inundation depth in ascending order of inundation depth, and this is taken as "height information". The “leaf number” is a identification field number uniquely assigned to each leaf node 4. The leaf ID can be written on the site using the wireless reader / writer when the leaf node 4 is installed.

  The portable terminal device 5 includes a touch panel / display 71, a position detection module 72, a map distribution request unit 73, a map receiving unit 74, a map display unit 75, a line communication interface 76, and a line communication antenna 77. The line communication interface 76 and the line communication antenna 77 are an interface and an antenna that exchange data with the public communication line 6. The touch panel display 71 is an electronic component in which a display device such as a liquid crystal panel and a position input device such as a touch pad are combined, and is an input / display device that operates the device by pressing a display on the screen. The position detection module 72 is a module for detecting mobile terminal position information representing the self position by the GNSS, and can use a generally used GPS receiving module or the like.

  The detailed functions of the above-described components will be collectively described in the description of the operation to be described later.

[2] System Operation The operation of the abnormal water level notification system of the present embodiment configured as described above will be described below.

(1) Initialization of Router Node FIG. 4 is a flowchart showing initialization processing of each router node. In the initialization process of the router node, immediately after installing each router node 3 and each leaf node 4 in the vicinity thereof, when installing a new leaf node 4 in the vicinity of the router node 3, or a leaf node in the vicinity of the router node 3 When 4 is removed or replaced, it is carried out only once.

  First, the router node 3 stands by until the initialization switch 44a provided in the router node 3 is pressed (S101). Here, the initialization switch 44 a is a push switch provided in the router node 3. It turns on when the installer of the router node 3 presses the initialization switch 44a with a finger, and turns off when the installer releases the finger.

  When it is detected in step S101 that the initialization switch 44a has been pressed, the initialization unit 44 of the router node 3 clears the leaf list stored in the leaf list storage unit 43 (deletes the data in the list). . Here, the “leaf list” is a list of leaf IDs included in leaf response signals that are normally received by the router node 3. The “leaf response signal” is a signal transmitted from the leaf node 4 in the vicinity of the router node 3 in response to the inquiry signal wirelessly transmitted to the surrounding space by the query issuing unit 45 of the router node 3. It is a signal including information on the leaf ID of the leaf node 4.

  Next, when the question transmitting unit 45 of the router node 3 wirelessly transmits the question signal to each leaf node 4 in the vicinity thereof to the surrounding space, and the leaf node receiving unit 62 of each leaf node 4 in the vicinity receives the question signal The leaf node response unit 63 generates a leaf response signal including the leaf ID stored in the leaf ID storage unit 61 and wirelessly transmits it to the surrounding space, and the response reception unit 46 of the router node 3 transmits it from each nearby leaf node 4 By performing a series of operations of receiving the received leaf response signal, the router node 3 performs a process of reading the leaf ID of each leaf node 4 in the vicinity thereof. In this process, collision of leaf response signals occurs when there are a plurality of leaf nodes 4 in the vicinity, so anti-collision technology such as time slot system or bit collision system (for example, 47 to 50 of Non-Patent Document 1) (See page). The initialization unit 44 of the router node 3 stores the received leaf ID of each nearby leaf node 4 in the leaf list storage unit 43 as a leaf list (S103, S210).

  Finally, the initialization unit 44 of the router node 3 receives a router signal transmitted by another router node 3 for a certain period of time by the telecommunication interface 49 and the telecommunication antenna 50, and the other router node 3 transmits The transmission timing and transmission channel which do not collide with the router signal to be transmitted are determined (S104). The subsequent transmission of the router signal from the router node 3 is performed using the transmission timing and transmission channel determined by the initialization unit 44 here.

  The leaf ID of the leaf node 4 installed in the vicinity of the router node 3 is stored in the leaf list storage unit 43 as a leaf list by the initialization processing operation of the router node 3 described above. The determination of the communication interruption of each leaf node 4 thereafter will be made by referring to this leaf list. At the same time, the transmission timing and transmission channel when the router node 3 transmits the router signal to the center node 2 are determined, and the collision avoidance with the router signal with other router nodes 3 is set.

(2) Notification of abnormal water level (2.1) Detection and notification of abnormal water level Next, an operation for detecting and reporting the occurrence of an abnormal water level will be described. FIG. 5 is a flow chart showing an operation of detection and notification of occurrence of abnormal water level in the abnormal water level notification system of FIG. 1.

  First, the router node 3 determines whether or not the detection timing time has been reached by the internal timer, and stands by until the detection timing time is reached (S111). The “detection timing time” refers to the time at which the detection of the abnormal water level is performed, and is a fixed time interval (for example, every five minutes).

  When the detection timing time is reached, next, the question transmission unit 45 of the router node 3 wirelessly transmits a question signal to each leaf node 4 in the vicinity to the surrounding space, and a leaf node reception unit of each leaf node 4 in the vicinity When the 62 receives the inquiry signal, the leaf node response unit 63 generates a leaf response signal including the leaf ID stored in the leaf ID storage unit 61 and wirelessly transmits it to the surrounding space, and the response reception unit 46 of the router node 3 By performing a series of operations of receiving a leaf response signal transmitted from each leaf node 4 in the vicinity, the router node 3 performs a process of reading the leaf ID of each leaf node 4 in the vicinity (S112, S211). This process is executed using anti-collision as in the case of the router node initialization process. At this time, the response receiving unit 46 simultaneously detects the received signal strength (hereinafter referred to as “RSS”) when the leaf response signal transmitted from each leaf node is received, and the inside along with the leaf ID. Save to memory

  Next, the water level detection unit 47 of the router node 3 collates the leaf ID of each leaf response signal received by the response reception unit 46 with the leaf list stored in the leaf list storage unit 43, and the communication is interrupted. A leaf ID of the leaf node 4 (Communication Disruption Leaf-node's ID: hereinafter referred to as "CDL ID") is detected (S113).

Here, when the CDL ID is not detected (S114), the water level detection unit 47 checks the RSS of the leaf response signal of each leaf node 4 from which the leaf response signal is received, and the RSS size and RSS The water level at the periphery of the leaf node 4 is detected by the magnitude of the variance (or standard deviation) of the sampling values (S115a). Specifically, the water level detection unit 47 distributes the RSS mean time U _ave (i) (i is an index of each leaf node 4) of the leaf response signal of each leaf node 4 in fine weather and the RSS sampled value The normal mean value (normal time variance value) σ ² _Uave (i) of the values is stored in advance in the internal memory. Then, in the time interval [t−Δt, t] of each time t, the interval average RSS of the leaf response signal of each leaf node 4 received in the time interval [t−Δt, t] U (i; t− The ratio of Δt, t) to the normal mean value U _ave (i) Ur (i; t-Δt, t) = U (i; t-Δt, t) / U _ave (i) value (ratio RSS), And the interval dispersion value σ ² _U (i; t-Δt, t) of the sampling values of the RSS of the time interval [t-Δt, t] and the time dispersion value σ ² _Uave (i) σ ² _Ur (i; t-Δt, t) = σ ² _U (i; t-Δt, t) / σ ² _Uave (i) is calculated (ratio RSS variance), this ratio RSS Ur (i; t-Δt, t) And the ratio RSS variance σ ² _Ur (i; t−Δt, t) to detect the water level around the leaf node 4. When the water surface approaches the bottom of leaf node 4 to a certain extent, the ratio RSS dispersion σ ² _Ur (i; t−Δt, t) gradually increases, and when the water surface approaches the bottom of leaf node 4, the ratio RSS Ur (i; t) -Δt, t) begins to decrease. Then, when the leaf node 4 is flooded, the ratio RSS Ur (i; t−Δt, t) drops rapidly, and when the flood becomes deep, the communication is interrupted. Therefore, some ratio RSS thresholds Urth (n) (n represents a ratio RSS determination level, n = 1, 2,...; Urth (1)> Urth (2)>...) And a ratio RSS dispersion threshold σ ² rth (m) (m represents the ratio RSS dispersion determination level, and m = 1, 2, ...; σ ² rth (1) <σ ² rth (2) <...) , By determining whether the ratio RSS Ur (i; t-Δt, t) falls below each threshold or whether the RSS variance σ ² _Ur (i; t-Δt, t) exceeds each threshold , Water level around the leaf node 4 can be detected. Here, the "water level" is a value obtained by dividing the detected water level in stages according to its height. For example, if m is 2 stages of 0 and 1 and n is 4 stages of 0, 1, 2 and 3, then
(0) Water level (n, m) = (0, 0) (Ur (i; t-Δt, t)> Urth (1) σ σ ² _Ur (i; t-Δt, t) <σ ² rth ( 1) is "water level not detected",
(1) Water level (n, m) = (0, 1) (Ur (i; t-Δt, t)> Urth (1) σ σ ² _Ur (i; t-Δt, t) σ σ ² rth ( 1)) "Water surface detection",
(2) Water level n = 1 (Urth (1) U Ur (i; t-Δt, t)> Urth (2)) is "water surface approach",
(3) The water level n = 2 (Urth (2) ≧ Ur (i; t-Δt, t)> Urth (3)) is “flooded” (the leaf node 4 has been flooded),
(4) The water level n = 3 (Urth (3) U Ur (i; t-Δt, t)) indicates that “communication is lost due to submersion” (the leaf node 4 is flooded and communication is lost.),
The water level is detected as As an alternative to the ratio RSS variance σ ² _Ur (i; t-Δt, t), the ratio RSS standard deviation σ _Ur (i; t-Δt, t), the average deviation of RSS, or the average value of RSS similar thereto You may use a statistic that represents the spread for.

The relationship between the leaf response signal ratio RSS Ur (i; t-Δt, t) and the ratio RSS dispersion σ ² _Ur (i; t-Δt, t) and the water level is described in more detail in Example 3. Do. Also, as a method of determining the water level from the RSS of the leaf response signal, other than this, the determination is performed by a method of machine learning such as deep layer learning using a neural network based on the pattern of temporal change of RSS. You can also.

  If it is determined that the water level is not detected in all leaf nodes 4 by this water level detection, the water level detection unit 47 outputs water level detection information in which the value indicating the water level detection (water level detection flag value) is invalid. On the other hand, when the water level is detected in any leaf node 4, the water level detection unit 47 indicates that among the leaf nodes 4, “height information” represents the height at which the inundation depth is the largest. The water level detection information including the maximum water level detection flag value and the detected height information, and the maximum water level detection level is determined for the water level level n detected at each leaf node 4 that has the largest inundation depth (maximum water level level). Output For example, when three leaf nodes 4 (hereinafter referred to as Lf1, Lf2 and Lf3) are registered in the leaf list in a certain router node 3, the height information of the leaf nodes Lf1, Lf2 and Lf3 is 0. , 1, 1 (the inundation depth is larger in height information 1 than height information 0, that is, height information 1 represents height higher than height information 0), and is detected at leaf node Lf 1 Assuming that the detected water level is 2 (flooded), the water level detected at leaf node Lf 2 is 1 (water approaching), and the water level detected at leaf node Lf 3 is 2 (flooded), the one with the largest water depth is , The water level 2 detected at the leaf node Lf3 of the height information 1. Therefore, the height information and the maximum water level included in the water level detection information are (height information, water level) = (1, 2). The water level detection signal transmission unit 48 transmits a router signal including the water level detection information, the router position information output from the position detection module 41, and the router ID stored in the router ID storage unit 42 to the telecommunication interface. It wirelessly transmits to the surrounding space by the wireless communication antenna 49 and the telecommunication antenna 50 (S115b).

  On the other hand, when the CDLID is detected in step S113 (S114), the water level detection unit 47 outputs the water level detection information including the valid water level detection flag value. At this time, the water level detection unit 47 adds, to the water level detection information, one of the “height information” extracted from the CDLID, which has the largest inundation depth, and adds the maximum water level (S116). For example, water level detection information is detected when CDLIDs whose height information included in CDLID is 0 and 1 (the inundation depth is greater for height information 1 than height information 0) are detected. 1 is added as “height information”, and the maximum water level (for example, water level 3 (communication interruption due to submersion)) is added as the water level. The water level detection signal transmission unit 48 transmits a router signal including the water level detection information, the router position information output from the position detection module 41, and the router ID stored in the router ID storage unit 42 to the telecommunication interface. It wirelessly transmits to the surrounding space by the wireless communication antenna 49 and the telecommunication antenna 50 (S117). After the process of step S115 or steps S116 and S117 described above, the router node 3 returns to step S111 again to repeat the same operation.

  On the other hand, the center node 2 installed indoors in each building B transmits the router signal transmitted from each router node 3 in the receivable range via the telecommunication antenna 26 and the telecommunication interface 25. It waits until the center node receiving unit 21 receives (S301). Here, the router signal transmitted from each router node 3 includes the “water level detection information”, the “router position information”, and the “router ID” as described above.

  When the router signal is received by the center node reception unit 21, the abnormality notification unit 22 of the center node 2 determines whether the water level detection flag value of "water level detection information" included in the router signal is valid or invalid, and the water level detection information It is determined whether the maximum water level detected in step is the level of "water level not detected" (level 0) (S302), and if the water level detection flag value is valid or other than maximum water level 0, go to the next step S303 Proceed, if the water level detection flag value is invalid and the maximum water level level 0, send "water level detection information", "router position information" and "router ID" of the router signal to the flood information collection and distribution server 1 (S304 ), Returns to step S301.

  If the water level detection flag value of “water level detection information” in the router signal in step S302 is valid or the maximum water level is equal to or higher than a certain level (for example, more than a value representing “water immersion”) The voice of the occurrence of is generated by the speaker 29 with an alarm sound and a warning voice, and the alarm lamp 30 is lit or blinked to notify the generation of the abnormal water level to the surroundings (S303). Here, the abnormality notification unit 22 refers to the shop-side node identification information Y of “router ID” included in the received router signal, and the shop-side node identification information Y indicates a value indicating the peripheral router node 3 b (for example, Y When = 1), the alarm level is L2, and when the house side node identification information Y is a value indicating the house side router node 3a (for example, Y = 0), the alarm level is L3. Then, in the case of the alarm level L2, the abnormality notifying unit 22 notifies the surroundings of the “needs attention alarm” indicating that the abnormal water level has been detected around the building by the speaker 29. In the case of the alarm level L3, the abnormality notifying unit 22 notifies the surroundings of the “emergency evacuation alarm” indicating that the abnormal water level has been detected in the middle of the building.

  Then, the abnormal water level information transmission unit 23 sets “water level detection information”, “router position information” and “router ID” included in the router signal as “abnormal water level information”, and makes the public communication line by the line communication interface 24. It transmits to the flood damage information collection distribution server 1 through 6 (S304), and returns to the operation of the above-mentioned step S301.

  As described above, a router signal is periodically transmitted from the router node 3 within the receivable range of the center node 2 at a constant time interval TR. Therefore, the center node 2 stores the router ID and the position information included in the router signal periodically received in normal time in the router list storage unit 31 as a router list. Then, among the router nodes 3 whose router IDs are registered in the router list, when it is detected that a router signal is not received for a predetermined threshold time Tth (> TR) or more (S301), the router of that router node 3 It is determined that the signal is broken (S305). This is because, for example, the water level becomes very high due to a flood, and when the router node 3 itself is submerged, or the rapid rise in water level such as in the case of debris flow or levee collapse, the router node 3 itself is submerged or washed away It corresponds to the case. When the router node 3 itself is submerged or lost, the transmission of the router signal from the router node 3 to the center node 2 is interrupted, and the center node 2 can not determine the abnormal water level by the router signal. Therefore, the center node 2 issues an alarm upon judging that the router node 3 itself is submerged or lost when the transmission of the router signal is interrupted. If it is determined in step S305 that the router signal is interrupted, the abnormality notification unit 22 notifies the occurrence of the abnormal water level to the surroundings by the speaker 29 and the alarm lamp 30 (S306), and the abnormal water level information transmission unit 23 communicates The "water level detection information", "router position information" and "router ID" of the router node 3 that has been disconnected are transmitted as "abnormal water level information" to the flood damage information collection distribution server 1 (S307), and the process returns to the operation of step S301. . The operation of step S306 is similar to that of step S303. Also, in step S307, the "water level detection information" of the router node 3 that has lost communication assumes that the "water level detection flag value" is valid, and adds a value representing the maximum water depth as "height information", It is transmitted to the flood damage information collection and distribution server 1 together with the “router position information” of the router node 3 whose communication is interrupted.

  As described above, when an abnormal water level (submersion) is detected in the router node 3 in the periphery, the center node 2 reports an alarm to the surroundings by the speaker 29 and the alarm lamp 30, and the residents in the building B or It can urge evacuation of residents. In addition, since this abnormal water level notification system, like a generally used fire alarm, when an abnormal water level is actually detected, a warning is automatically notified without the intervention of the administrative decision, so residents Alternatively, the resident can make a quick evacuation judgment, and at the same time the disaster prevention organization such as the administration can grasp the local situation in real time.

  In this embodiment, each leaf node 4 receives an interrogation signal from the router node 3 and returns a leaf response signal. However, other than this, the internal power source (battery) is used as the leaf node 4. Using the active leaf node 4, the leaf node 4 can be configured to periodically transmit a leaf response signal at a constant time interval even without receiving an interrogation signal. In this case, in step S112, the process in which the question sending unit 45 of the router node 3 sends a question signal is omitted, and the question sending unit 45 may be omitted in the router node 3.

(2.2) Distribution of flood occurrence map information by flood information collection distribution server When an abnormal water level occurs around building B and center node 2 reports an alarm to the surroundings, residents or residents of building B are buildings It is necessary to take refuge from B. In this case, the abnormal water level around the building B is very useful if there is information on the point of occurrence and the roads that can be passed. Therefore, in this section, distribution processing of flood occurrence map information in which the abnormal water level indicates information on an occurrence point or a passable road will be described.

  FIG. 6 is a flowchart showing an update process of the flood damage information database 17 and the flood damage map database 18 in the abnormal water level notification system of FIG. First, the flood damage information collection distribution server 1 stands by until the "abnormal water level information" is transmitted from the center node 2 (S401). The "abnormal water level information" is information including the "water level detection information", the "router position information", and the "router ID" as described above. When receiving the "abnormal water level information" transmitted from the center node 2, the server-side receiver 11 of the flood information collection and distribution server 1 receives "water level detection information" and "router position information" included in the "abnormal water level information". And “router ID” and the reception time of the “abnormal water level information” are stored in the flood damage information database 17 (S402).

  Next, the map information acquisition unit 12 receives “route location information” included in the “abnormal water level information” from the map delivery server or the map database 10 connected to the flood damage information collection delivery server 1 via the public communication line. Map information of the surroundings is acquired (S403). Here, the map database 10 stores an electronic map such as an electronic land map provided by the Geographical Survey Institute. The "map distribution server connected to the flood information collection distribution server 1 via a public communication line" is, for example, a distribution server of an electronic map distributed on the Internet.

  Next, based on the received “water level detection information” and “router position information” and the extracted map information, the flood occurrence map generation unit 13 of the water damage information collection distribution server 1 indicates the position indicated by the router position information. Of the inundation estimation range around S. (S404). The extraction of the inundation estimation range is performed in accordance with a predetermined rule based on elevation data of each point of the map information and hazard map data stored in advance in the map database 10. At this time, when there is “information on position correction” for “router ID” included in the “abnormal water level information” in the measurement point correction database 19, when extracting the inundation estimation range, The “router position information” corrected based on the “information on position correction” is used. In addition, when the water level detection flag value of the "water level detection information" is an invalid value, it means that no abnormal water level is generated around the router node 3 in the "router position information". There is no estimated range (NULL).

  Next, the flood occurrence map generation unit 13 extracts roads (including roadways, walkways, and garden roads) included in the extracted estimated inundation area, and sets the extracted road area as an estimated inundated road area (S405). ).

  Then, the flood occurrence map generation unit 13 displays, on the map, the water level information at the position indicated by the “router position information”, the inundation estimation range, and the estimated inundation road range information from the inundation estimation range and the inundation road range. Transaction data (hereinafter referred to as "flood occurrence transaction data") is generated and stored in the flood damage map database 18 in association with the "router ID" included in the "abnormal water level information" (S406). Here, if there is a record (existing record) regarding the same “router ID” as the “router ID” in the flood map database 18, the flood occurrence transaction data of the record is generated as a new flood occurrence created here Update to transaction data. Further, in the case where there is an existing record of the same "router ID" and there is no inundation estimation range (NULL), the existing record is deleted. After updating the flood damage map database 18 in this manner, the operation returns to the operation of the step S401.

  By the above operation, the "abnormal water level information" transmitted from each center node 2 is sequentially stored in the flood damage information database 17 in the flood damage information database 17, and the information on the inundation range which changes momentarily is a map. The flood damage transaction data of the flood damage map database 18 is updated in real time while being stored in the flood damage map database 18 as transaction data (flood damage transaction data) for display.

  FIG. 7 is a diagram showing an example of flood occurrence map information displayed using the flood occurrence transaction data generated by the flood occurrence map generation unit 13. In FIG. 7, the points indicated by “o” “Δ” “x” are the positions indicated by “router position information”, “o” indicates no water immersion, “Δ” indicates water immersion below knees, and “x” indicates knees above knees It indicates the inundation depth of the above inundation. In addition, flooded areas above knees and flooded areas below knees are shown in blue and light blue on the map, road areas within flooded areas above knees are shown red, and road areas within flood areas below knees are indicated orange. (Here, since FIG. 7 is a black-and-white gray-scale image, the color information is converted to grayscale). Further, the mark of the house represents the position of the building B in which the center node 2 is installed (discriminated from the “door side node identification information” included in the “router ID”). The flood occurrence transaction data is a command sequence for displaying symbols such as “○” “Δ” “×” on the map, road lines in the flooded area, and displaying the flooded area.

  FIG. 8 is a flowchart showing an operation of distribution processing of flood occurrence map information in the abnormal water level notification system of FIG. The distribution of the flood occurrence map information is performed via the public communication line 6 with respect to the portable terminal device 5 owned by a resident or resident of the building B.

  First, in the mobile terminal device 5, a display instruction of a flood occurrence map is input by the user from the touch panel display 71 (S500). When the display instruction is input, the map distribution request unit 73 detects the position information indicating the own position by the position detection module 72 (S501). Next, the map distribution request unit 73 transmits the map distribution request together with the position information of the own position to the flood information collection and distribution server 1 through the public communication line (S502).

  When the flood damage information collection distribution server 1 receives the map distribution request and the position information transmitted from the portable terminal 5 (S421), first, the map distribution unit 14 transmits the map database 10 or public communication by the map information acquisition unit 12. From the map distribution server connected to the flood information collection and distribution server 1 via a line, map information in a predetermined range centered on the designated position designated by the position information (hereinafter referred to as "designated position peripheral map information") Acquire (S422). Next, the map distribution unit 14 extracts flood occurrence transaction information related to the designated position surrounding map information from the flood map database 18 (S423). Here, "flood occurrence transaction information related to the specified position peripheral map information" refers to flood occurrence transaction information that displays abnormal water level occurrence information at a point on the map within the range of the specified position peripheral map information. is there. Next, the map distribution unit 14 generates flood occurrence map information in which flood occurrence information is displayed in the map of the specified position peripheral map information based on the extracted flood occurrence transaction information (S424). This can be done by executing the transaction of the extracted flood occurrence transaction information on the designated position peripheral map information. Then, the map distribution unit 14 distributes the generated flood occurrence map information to the portable terminal device 5 that has transmitted the map distribution request and the position information (S425).

  When the map receiving unit 74 receives the flood occurrence map information transmitted from the flood information collection distribution server 1 in response to the map distribution request in the portable terminal device 5 (S 503), the map display unit 75 receives the flood occurrence map received. The information is displayed on the touch panel display 71 (S504). The flood occurrence map information displayed on the touch panel / display 71 is, for example, a flood occurrence map as shown in FIG.

  In this manner, the resident or resident can grasp the flood occurrence situation in the vicinity of the building B in real time by the resident or resident in the building B browsing the flood occurrence map information from the portable terminal device 5 Can do. Thereby, the resident or resident can accurately determine whether to evacuate or stay, and when evacuating, the evacuation route can be determined while confirming the occurrence of flood damage in real time by the portable terminal device 5 You can choose.

(2.3) Collection and distribution of wide area water level detection information in the flood information collection and distribution server The detection and notification operation of the abnormal water level described in (2.1) above is an abnormal water level around building B where the center node 2 is installed. Detection and notification of the narrow area water level detection information that has occurred. On the other hand, although there is no abnormal water level around Building B, it is an abnormal water level that causes the area where Building B is present, such as the area above Building B, to be affected by flood damage. It is considered that there is a high possibility that an abnormal water level will occur in the area around Building B. Therefore, it is considered useful to report wide area water level detection information including the upstream area of the area where the building B is located. Therefore, in this section, collection and delivery of wide area water level detection information and notification processing will be described.

  FIG. 9 is a flowchart showing the operation of the flood warning distribution process in the abnormal water level notification system of FIG. First, “abnormal water level information” is transmitted to the flood damage information collection and distribution server 1 from one of the center nodes 2 installed in the buildings B in various places. As described above, the “abnormal water level information” includes the “router position information” and the “router ID” of the router node 3 that has detected the abnormal water level, and the “water level detection information”. When receiving the "abnormal water level information" (S431), the flood warning information transmitting unit 15 of the water damage information collection distribution server 1 receives the "router position information" included in the "abnormal water level information", the "router location information" The map information acquisition unit 12 acquires a predetermined range around “position information” and map information of a downstream area downstream of the “router position information”. The periphery and the downstream area of the "router position information" extracted here are called "flood warning notification area". Next, the flood warning information transmitting unit 15 extracts center node related information whose position information is included in the flood warning issuance area from the center node related information stored in the center node list storage unit 20. (S433) A "waterfall warning" is transmitted via the public communication line 6 to the network address of the extracted center node related information (S434). Here, the "flood warning" is information for notifying that there is a flooded area in the upper watershed of building B, and is information of the alarm level L1 (see the above-mentioned "[1] system configuration" section). is there.

  The anomaly notification unit 22 of the center node 2 that has received the "flood warning" sent from the flood information collection and distribution server 1 (S321) detects an abnormal water level upstream of the building by the speaker 29 and the alarm lamp 30 The "flood warning" indicating that is notified to the surroundings (S322).

  By the operation as described above, in the buildings B in various places where the center node 2 is installed, it is possible to report wide area water level detection information including the upstream area of the area where the building B is located.

  In the present embodiment, the leaf node 4 receives an interrogation signal wirelessly transmitted from the router node 3 to the surrounding space, and transmits a leaf response signal in response to the interrogation signal (question response system) Although the steps S111 to S113 and S211 in FIG. 5 have been described, the leaf response signal transmission method in the leaf node 4 is not limited to the interrogation signal from the router node 3 except for each leaf node. It can also be configured in a case where the leaf response signal is transmitted intermittently at predetermined time intervals (push method). In this case, the parts of steps S111 to S113 and S211 in FIG. 5 may be changed as shown in FIG. 10, for example.

  In FIG. 10, the leaf node 4 transmits a leaf response signal once during a fixed cycle time Tc. First, after resetting the internal timer (S211), the leaf node response unit 63 of the leaf node 4 determines the transmission timing Ts (S222), and starts the internal timer (S223). The “transmission timing” is a time Ts from the start of the internal timer to the transmission of the leaf response signal, and is randomly determined by random numbers in the range of 0 <Ts <Tc. Here, the transmission timing Ts is randomly determined in order to prevent the leaf response signal of the leaf node 4 from colliding with the leaf response signal of another leaf node 4 in the router node 3. When the clocked time t of the internal timer reaches the transmission timing Ts (S224), the leaf node response unit 63 of the leaf node 4 generates a leaf response signal including the leaf ID and wirelessly transmits it to the surrounding space (S225). Then, after waiting until the counted time t of the internal timer reaches the cycle time Tc (S226), the process returns to step S221. As a result, during one cycle time Tc, one leaf node 4 transmits a leaf response signal once.

  On the other hand, in the router node 3, a list (leaf list) of leaf IDs of the leaf nodes 4 in the vicinity from which leaf response signals are normally transmitted is registered in the leaf list storage unit 43 in advance. In this state, the response receiving unit 46 receives the leaf response signal transmitted from each leaf node 4 during one cycle time Tc by starting the internal timer, and the leaf ID included in the received leaf response signal And generate a list (reception leaf list) of the reception strength of the leaf response signal (S111 ′, S112 ′). When the clocked time t of the internal timer reaches one cycle time Tc, the water level detection unit 47 collates the received leaf list with the leaf list stored in the leaf list storage unit 43, and each leaf in the vicinity of the router node 3 It is determined whether the node 4 has interrupted the transmission of the leaf response signal (S113 '). The following steps follow step S114 described above, as in FIG. In this manner, the leaf response signal is transmitted by the leaf response signal that each nearby leaf node 4 spontaneously transmits once every one cycle time Tc regardless of the query signal of the query transmission unit 45. It is also possible to detect the interrupted leaf node 4 at the router node 3 and detect the occurrence of an abnormal water level and the inundation depth.

  FIG. 11 is a diagram illustrating the entire configuration of the abnormal water level notification system according to the second embodiment of the present invention. The abnormal water level notification system of the present embodiment is different from the first embodiment in that a relay node 7 is newly added. The relay node 7 is a node that relays transmission when transmitting a router signal from the router node 3 to the center node 2. The relay node 7 includes a relay node ID storage unit (not shown) that stores a relay node ID that is an identification code of itself. When the relay node 7 receives a router signal transmitted from the router node 3 or another relay node 7, the relay node 7 adds the relay node ID stored in the relay node ID storage unit as routing information to the router signal. Wireless transmission to the surrounding space. At this time, when the relay node ID of its own is added as the routing information to the router signal, the router signal is discarded, and wireless transmission to the surrounding space is not performed. This prevents the router signal from infinitely circulating among the plurality of relay nodes 7. Thus, by introducing the relay node 7, each center node 2 can receive a router signal from the router node 3 in a wider range, and can report occurrence of an abnormal water level in a wider range. In particular, in a mountainous area, it is difficult to install many center nodes 2 because it is difficult for radio waves in wireless communication to reach a long distance due to surrounding mountains, and buildings such as private houses and business establishments are sparse. In such a case, by extending the abnormal water level detection area covered by one center node 2 using the relay node 7, it is possible to perform notification of the appropriate abnormal water level.

  In this embodiment, an example will be described in which the water level detection from the RSS U (i, t) of the leaf response signal of each leaf node 4 communicating with each router node 3 is performed in each center node 2. In addition, the whole structure of the abnormal water level alerting | reporting system in a present Example presupposes that it is the same as that of FIG. FIG. 12 is a block diagram showing the functional configuration of the abnormal water level notification system according to the third embodiment. Compared with FIG. 3 of the first embodiment, the point that the water level detection unit 32 is newly added to the center node 2 is different.

  The operation of the abnormal water level alarming system of the third embodiment is basically the same as that of the first embodiment, but in the present embodiment, the water level detection unit 47 of the router node 3 has each leaf in step S115a of FIG. Assuming that (leaf ID, RSS, height information) of the leaf response signal of the node 4 is the water level detection information, the water level detection signal transmitting unit 48 determines the water level detection information and the router position outputted by the position detection module 41 in step S115b. The telecommunication interface 49 and the telecommunication antenna 50 wirelessly transmit the router signal including the information and the router ID stored in the router ID storage unit 42 to the surrounding space.

  Further, in step S116 of FIG. 5, the water level detection unit 47 validates the water level detection flag value and extracts the one with the largest water immersion depth out of the "height information" extracted from the CDLID, and the valid water level detection flag A value, detected height information, and (leaf ID, RSS, height information) information of each received leaf response signal are output as water level detection information. The water level detection signal transmission unit 48 transmits a router signal including the water level detection information, the router position information output from the position detection module 41, and the router ID stored in the router ID storage unit 42 to the telecommunication interface. It wirelessly transmits to the surrounding space by the wireless communication antenna 49 and the telecommunication antenna 50 (S117).

  That is, in the present embodiment, the router node 3 does not estimate the water level from the RSS of each leaf response signal, and the information of the RSS itself is the center node together with the "height information" of the leaf node 4 related to the leaf response signal. Send to 2

  In the center node 2, the water level detection unit 32 obtains the RSS of the leaf response signal of the leaf node 4 around the router node 3 from the router signal sent from each router node 3, and Detect the water level in the surrounding area. The water level detection is the same as the method described in step S115a of the first embodiment. Then, the abnormality notification unit 22 detects that the water level detected by the water level detection unit 32 is equal to or higher than a certain level (for example, equal to or higher than a value representing “water immersion”), or “water level detection information in the router signal When the water level detection flag value of “1” is valid, the occurrence of the abnormal water level is voiced with the alarm sound and the warning sound by the speaker 29, and the alarm lamp 30 is lit or blinked to generate the abnormal water level. To the surrounding area.

  As described above, the detection of the water level in the periphery of each leaf node 4 may be performed in a centralized manner at the center node 2 instead of each router node 3.

Finally, the relationship between the RSS U (i, t) of the leaf response signal received by the router node 3 and the water level will be described. In the case where a leaf response signal is transmitted from the leaf node 4 to the router node 3, it is assumed that there is a water surface below the leaf node 4. Here, in order to facilitate the principle explanation, it is assumed that the water surface is a static water surface without any waves. In this case, the transmission path of the leaf response signal is as shown in FIG. In FIG. 13, assuming that leaf node 4 is transmission point A and router node 3 is reception point B, and points A and B are on the hydrostatic surface, as shown in FIG. 13, in the vertical plane including points A and B. Then, an xy coordinate system in which the x axis is horizontally oriented and the y axis vertically oriented is set. The coordinates of the transmitting point A are (0, y _A ), the coordinates of the receiving point B are (x _B , y _B ), and the water surface is y = y ₀ . Assuming that the electromagnetic wave (leaf response signal) emitted from the transmission point A is a spherical wave that spreads radially, the path of the electromagnetic wave reaching the reception point B is (1) direct from the transmission point A to the reception point B Path to travel p _AB (2) Path reflected from transmission point A to reflection point C on the water surface, path p _ACB to reception point B (3) From transmission point A to refraction at refraction point D on water surface, into water It is conceivable that there is a path p _ADECB,. The frequency of the electromagnetic wave assumed here is the frequency band (900 MHz to several GHz) used in RFID, Bluetooth (registered trademark), etc. In this frequency band, the reflectivity of the electromagnetic wave on the water surface is large, and underwater Since the attenuation of the electromagnetic wave at is also considered to be large, only the paths p _AB and p _ACB are considered here. The distance to the transmitting point A from the surface y _A0, the distance from the water surface to the receiving point B to _{y B0, h BA = y B} -y A. At this time, the path length l _AB of the path p _AB, the path length l _ACB path p _ACB, x-coordinate x _C of the reflection point C of the path p _ACB, incidence and reflection angle of the reflection point C theta _C, and at the receiving point B The angle θ _B formed by the paths p _AB and p _ACB is often expressed as follows.

Further, the electric field components of the electromagnetic wave incident on the receiving point B through the paths p _AB and p _ACB are E ₁ and E ₂ respectively, and the components in the xy plane of the electric fields E ₁ and E ₂ (p polarization component _E.sub.1p , _E.sub.2p , components in the direction perpendicular to the xy plane (s-polarization components) are _E.sub.1s , _E.sub.2s, and _E.sub.1p , _E.sub.2p , _E.sub.1s , _E.sub.2s are often expressed as follows. (See Figure 14).

Here, i ₁ and i ₂ are unit vectors representing the directions of the electric fields E ₁ and E ₂ respectively, i _z is a unit vector of the direction perpendicular to the xy plane, ω is the angular frequency of the electromagnetic wave, φ ₁ and φ ₂ is often the phase shift amount of the electromagnetic waves E ₁ and E ₂ with respect to the transmission point A at the reception point B.

At this time, the time averages U _Ep ^(ave) and U _Es ^(ave) of the energy density of the p polarization electric field and the s polarization electric field at the reception point B are often expressed as follows.

Further, assuming that the wavelength of the electromagnetic wave is λ, the phase shift amounts φ ₁ and φ ₂ are expressed as follows.

Now, assuming that the electromagnetic wave emitted from the transmission point A is a spherical wave, the energy density of the electromagnetic wave attenuates in proportion to 1 / l ^2, where l is the optical path length from the transmission point A. Accordingly, p-polarized light of the electric field component of the electromagnetic wave in the transmitting point A, s-polarized light of the size of the E _0p, when the _{E 0s, E 10p, E 20p} , E 10s, E 20s can be expressed as其s next .

Here, R _p and R _s are the intensity reflectances on the water surface of p-polarized light and s-polarized light, respectively, and assuming that the refractive index of water is n (n = 8.94 at a frequency of 2.4 GHz (water temperature 10 ° C.)) It is expressed as

According to each of the above equations, the time average U _Ep ^(ave) of the relative energy density of the electric field component of the electromagnetic wave received at the reception point B (value obtained by dividing the electric field energy density of the reception point B by the electric field energy density of the transmission point A ⁾ , U _Es ^(ave) and the height y _{A0 of the} water surface are calculated as shown in FIG. 15 and FIG. Here, h _BA = 1 m, in FIG. 15 x _B = 1 m, and in FIG. 16 x _B = 10 m. From FIG. 15 and FIG. 16, as the water surface approaches the transmission point A, the interference between the direct wave and the reflected wave becomes larger, so the change in y _A0 of the relative energy density of the electric field component of the electromagnetic wave received at the reception point B Vibration increases. Since the actual water surface vibrates pseudo-randomly, it is observed as a phenomenon that the dispersion of the reception intensity of the electromagnetic wave at the reception point B becomes larger as the water surface approaches the transmission point A.

  FIG. 17 shows the results of measurement of changes in reception intensity due to changes in the distance between the transmission point A and the water surface using an active beacon in a laboratory. In FIG. 17, the horizontal axis represents time, and the vertical axis represents reception intensity (dB). Moreover, FIG. 18 is a figure which shows the measurement conditions of the measurement of FIG. For measurement, place a pole in the water tank, change the height at intervals of 125 cm, install an active beacon, inject water into the water tank, and receive the strength of the signal transmitted from each beacon by the receiver outside the water tank Carried out by observing the The measurement results of (a), (b) and (c) in FIG. 17 show the reception strengths of the signals from the beacons in (a), (b) and (c) of FIG. 18, respectively.

From FIG. 17, when water starts to be poured into the water tank, the dispersion of the reception intensity starts to increase, and the dispersion of the reception intensity increases as the water surface approaches each beacon. This is because, as the water surface approaches the beacon, the influence of interference between the direct wave and the reflected wave propagating from the beacon to the receiving antenna increases (FIGS. 15 and 16), and the change in reception intensity due to the water surface fluctuation increases. It is understood that it is. As the water surface approaches the beacon further, the average value of the reception intensity starts to gradually decrease and the effective sampling number of the reception signal (the number of successfully received signals) starts to decrease from the vicinity of 10 cm or less. This is because, when the water surface is very close to the beacon, the incident angle of the reflected wave to the water surface approaches the Brewster's angle, so that the p-polarized wave is less reflected, and the overall reception intensity is reduced accordingly. It is understood that it is. FIG. 19 is a graph showing changes in the intensity reflectances R _p and R _s of water with respect to the incident angle θ _{C at} a frequency f = 2.4 GHz. From FIG. 19, at the frequency f = 2.4 GHz, the Brewster angle of air-water reflection is about 84 degrees, and the reflectance of p polarized light wave is rapid from the vicinity where the incident angle θ _C exceeds 60 degrees. It turns out that it has fallen.

  Then, when the beacon is submerged, the reception intensity drops sharply. It is understood that this is because radio waves emitted from underwater beacons are reflected and refracted on the water surface. Since the refractive index is large at the frequency f = 2.4 GHz, the refraction angle of the electromagnetic wave incident on the water surface from water is approximately 90 degrees, and most of the refracted waves propagate along the water surface, so they are separated from the water surface The field intensity reaching the receiving antenna at the position is considered to be greatly weakened. Furthermore, if the water depth of the beacon becomes large after being submerged, the radio wave emitted from the beacon in the water is greatly attenuated in the water, and the reception intensity is further sharply reduced, resulting in the communication interruption.

  Therefore, it can be understood that it is possible to detect that water immersion has started by observing the increase in the variance of the reception strength of the signal from the transmission point (leaf node 4) at the reception point (router node 3) . In addition, it can be understood that it is possible to detect that the transmission point (leaf node 4) is close or submerged by observing a decrease in the average value of the reception strength.

  FIG. 20 is a diagram showing an entire configuration of an abnormal water level notification system according to a fourth embodiment of the present invention. The abnormal water level notification system of the present embodiment basically has the same configuration as that of the first embodiment, but the portable terminal device 5 is configured to also function as the router node 3 (hereinafter referred to as “portable terminal Terminal device 5, 3 "). That is, the portable terminal devices 5 and 3 have the touch panel / display 71, the position detection module 72, the map distribution request unit 73, the map receiving unit 74, the map display unit 75, the line communication interface 76, and the line communication antenna 77 shown in FIG. In addition to the above functions, as shown in FIG. 21, the position detection module 41, the router ID storage unit 42, the leaf list storage unit 43, the initialization unit 44, the initialization switch 44a, the question transmission unit 45, the response reception unit 6, the water level It also has the functions of a detection unit 47, a water level detection signal transmission unit 48, a telecommunication interface 49, a telecommunication antenna 50, a short distance communication interface 51, and a short distance communication antenna 52. Furthermore, when the water level detection unit 47 generates the water level detection information in which the value indicating the water level detection is valid, the portable terminal devices 5 and 3 notify the occurrence of the abnormal water level to the surroundings by voice or display. A section 78 and a speaker 79 are provided. Here, a smart phone or a tablet can be used as the mobile terminal device 5.

  Thus, by causing the portable terminal devices 5 and 3 to function as the router node 3 as well, if the resident or resident always carries the mobile terminal devices 5 and 3, the resident or resident may use the abnormal water level notification system. Within the range covered, it is possible to know the occurrence of an abnormal water level in real time in response to a signal from the leaf node 4 regardless of where it is, which leads to a prompt evacuation of residents or residents.

  In the present embodiment, only the portable terminal devices 5 and 3 of the router node 3 are provided with the abnormality notifying unit 78 and the speaker 79, but all the router nodes 3 have the abnormality notifying unit 78 and the speaker It can also be configured to have 79.

  FIG. 22 is a diagram illustrating the entire configuration of the abnormal water level notification system according to the fifth embodiment of the present invention. The abnormal water level notification system according to the fifth embodiment is basically the same as the abnormal water level notification system according to the fourth embodiment, but each router node 3 and each center node 2 are an ad hoc network (multi-hop wireless network) It differs in that it was connected by. In this case, the role of the network coordinator is assumed to be handled by one of the center nodes 2. Such an ad hoc network configuration can be easily realized by, for example, Bluetooth (registered trademark). Thus, by connecting each router node 3 and each center node 2 by an ad hoc network, each router node 3 and each center node 2 also have a function as a relay node 7. Therefore, even if some router nodes 3 or center nodes 2 lose communication due to flooding etc., router nodes 3 or center nodes 2 for which communication has not been lost due to the multipath routing protocol. Network communication can be continuously performed via the network, and communication robustness of the entire system can be improved.

  FIG. 23 is a diagram illustrating the entire configuration of the abnormal water level notification system according to the sixth embodiment of the present invention. The abnormal water level notification system according to the sixth embodiment is basically the same as the abnormal water level notification system according to the fifth embodiment, but is different in that the center node 2 and the house side router node 3a are united. That is, the center nodes 2 and 3 in FIG. 23 also have the functional configurations of the house side router node 3a. By doing this, the network configuration can be simplified and the system can be introduced at a lower cost. Incidentally, as the center nodes 2 and 3, it is also possible to use a smart meter which is currently spreading.

DESCRIPTION OF SYMBOLS 1 Flood information collection delivery server 10 Map database 11 Server side reception part 12 Map information acquisition part 13 Flood occurrence map generation part 14 Map delivery part 15 Flood caution information dispatch part 16 Circuit communication interface 17 Flood information database 18 Flood map database 19 Measurement point Correction database 20 Center node list storage unit 2 Center node 21 Center node receiver 22 Abnormality information unit 23 Abnormal water level information transmitter 24 Line communication interface 25 Long-distance communication interface 26 Long-distance communication antenna 27 Short-distance communication interface 29 Speaker 30 Alarm lamp 31 router list storage unit 32 water level detection unit 3 router node 3 a shop side router node 3 b peripheral router node 41 position detection module 42 router ID storage unit 43 leaf list storage unit 4 4 initialization unit 44a initialization switch 45 question transmission unit 46 response reception unit 47 water level detection unit 48 water level detection signal transmission unit 49 long distance communication interface 50 long distance communication antenna 51 short distance communication interface 52 short distance communication antenna 4 leaf node 61 Leaf ID storage unit 62 Leaf node reception unit 63 Leaf node response unit 64 Short distance communication interface 65 Short distance communication antenna 5 Portable terminal device 71 Touch panel display 72 Position detection module 73 Map distribution request unit 74 Map reception unit 75 Map display unit 76 Line communication interface 77 Line communication antenna 6 Public communication line 7 Relay node B Building

Claims (10)

An abnormal water level notification system that detects and reports the occurrence of an abnormal water level due to rainfall.
A center node installed indoors in the building;
One or more router nodes installed indoors or outdoors around the center node;
One or more leaf nodes installed in the vicinity of each of the router nodes;
The router node is
Router node position output means for detecting and outputting router position information representing self position by the global positioning satellite system, or outputting router position information representing self position recorded in advance in position information storage means;
Response receiving means for receiving a leaf response signal transmitted from each leaf node in response to an interrogation signal wirelessly transmitted to the surrounding space with respect to each leaf node, or intermittently at predetermined time intervals;
Based on the presence or absence of transmission of the leaf response signal among the leaf nodes, or based on the intensity change of the leaf response signal, the presence or absence of water approaching or inundation is determined, and it is determined that there is water approaching or inundation. A water level detection unit that generates water level detection information in which a value indicating water level detection is validated when it is determined;
Water level detection signal transmission means for wirelessly transmitting the water level detection information output by the water level detection means to the center node together with the router position information;
The leaf node is
Leaf ID storage means for storing a leaf ID which is an identification code of the leaf node;
When the inquiry signal transmitted from the router node is received, or intermittently at predetermined time intervals, the leaf response signal including the leaf ID stored in the leaf ID storage means is generated and wirelessly transmitted to the surrounding space Providing a leaf node response means to transmit;
The center node is
A communication interface that communicates with the outside via a public communication line;
Center node receiving means for receiving the water level detection information and the router position information wirelessly transmitted from the router node;
When the center node reception means receives the water level detection information and the router position information, when the value indicating the water level detection of the water level detection information is valid, the occurrence of the abnormal water level is notified to the surroundings by voice or display. 1 anomaly notification means,
When the center node reception means receives the water level detection information and the router position information, if the value indicating the water level detection of the water level detection information is valid, the water level detection information and the router position information An abnormal water level information transmission means for transmitting to an external flood information collection and delivery server via a line,
An abnormal water level notification system characterized by comprising. A plurality of the center nodes arranged in buildings at various places;
A flood information collection and delivery server connected to the center node via a public communication line;
The flood damage information collection delivery server is
Flood damage map database which manages flood occurrence transaction information which is transaction information for displaying occurrence information of abnormal water level on the map,
Server side receiving means for receiving the water level detection information and the router position information transmitted from each of the center nodes;
Map information acquisition means for acquiring map information from a map distribution server via a public communication line or from a map database provided in the flood damage information collection distribution server;
A flood occurrence map generation unit that generates the flood occurrence transaction information based on the received water level detection information, the router position information, and the map information and stores the flood occurrence transaction information in the flood map database;
In accordance with a map distribution request and position information transmitted from the outside via a public communication line, map information of a predetermined range centered on a designated position designated by the position information by the map information acquisition means (hereinafter referred to as “ "Designated location surrounding map information" is displayed and flood occurrence information is displayed in the designated location surrounding map information based on the flood occurrence transaction information related to the designated location surrounding map information extracted from the flood damage map database Map distribution means for generating the generated flood damage map information and distributing the flood damage map information;
The abnormal water level notification system according to claim 1, comprising: A plurality of leaf nodes are installed at different heights near each of the router nodes, and the leaf ID storage means of each leaf node has a height assigned according to the height. The leaf ID including the information is stored.
The router node comprises leaf list storage means for generating and storing a list of leaf IDs included in the leaf response signal normally received at the router node,
The water level detection means of the router node extracts the leaf ID of the leaf node for which the reply of the leaf response signal is interrupted with respect to the inquiry signal among the leaf IDs stored in the leaf list storage means Generating the water level detection information including the height information included in the extracted leaf ID;
The flood occurrence map generation means of the flood information collection and delivery server is based on the water level detection information including the received water level information, the router position information, and the map information, the occurrence position of the abnormal water level and the occurrence position thereof. The abnormal water level notification system according to claim 2, characterized in that it generates flood damage map information indicating the water level on a map.   The flood occurrence map generation means acquires elevation data around the position indicated by the router position information from the map information based on the received router position information, and the position information based on the acquired elevation data 4. The flood damage estimation map according to claim 2 or 3, wherein the inundation estimation range around the position indicated by is extracted, and the flood occurrence map information indicating the occurrence position of the abnormal water level and the inundation estimation range on a map is generated. Abnormal water level notification system described.   The flood occurrence map generation means acquires elevation data around a position indicated by the router position information and route information of a road from the map information based on the received router position information, and the position information indicates the position indicated by the position information. The inundation estimation road range which is a road range included in the inundation estimation range is extracted while extracting the inundation estimation range of the surrounding, and the flood occurrence map information showing the generation position of the abnormal water level and the inundation estimation road range on the map The abnormal water level notification system according to claim 2 or 3, characterized in that A portable terminal connected to the flood information collection and delivery server via a public communication line;
The portable terminal device is
A display,
Mobile terminal position detection means for detecting position information representing self position by a global positioning satellite system;
Map distribution request means for transmitting the map distribution request to the flood damage information collection distribution server via a public communication line together with the position information detected by the portable terminal position detection means;
Map receiving means for receiving the flood occurrence map information transmitted from the flood information collection and delivery server via a public communication line in response to the map delivery request;
Map display means for displaying the flood occurrence map information received by the map reception means on the display;
The abnormal water level notification system according to any one of claims 2 to 5, further comprising: Each of the router nodes comprises router ID storage means for storing a router ID which is an identification code of the router node,
The water level detection signal transmission unit of each of the router nodes wirelessly transmits the water level detection information output by the water level detection unit to the center node as water level detection information together with the router position information and the router ID. ,
Each router node is a house side router node installed near the ground side or indoor side of a building where the center node is installed, and a peripheral router node installed at each place away from the building where the center node is installed. The router ID of the shop-side router node includes shop-side node identification information identifying the shop-side router node,
The first anomaly notification means of the center node is
When the center node reception means receives the water level detection information and the router ID wirelessly transmitted from the router node,
If the router ID indicates that the shopside node identification information is a peripheral router node, a warning alert is notified to the surroundings indicating that an abnormal water level has been detected around the building,
When the router ID indicates that the store side node identification information is a store side router node, an emergency evacuation alert indicating that an abnormal water level has been detected in the middle of a building is notified to the surroundings. The abnormal water level notification system according to any one of claims 2 to 6, wherein The flood damage information collection delivery server is
When the server-side receiving unit receives the water level detection information and the router position information transmitted from the center node,
Based on the map information, among the buildings in which each of the center nodes is installed, a building which is estimated to be affected by a flood with respect to a position specified by the router position information is extracted;
A flood warning information transmitting means for transmitting flood warning information via public communication lines to each of the center nodes installed in the extracted building;
The first anomaly notification means of the center node detects that an abnormal water level is detected upstream of the building when the flood warning information transmitted from the flood information collection and distribution server is received through a public communication line. The abnormal water level notification system according to claim 7, characterized in that a flood warning to be shown is notified to the surroundings.   The abnormal water level notification system according to any one of claims 1 to 8, wherein a part of the router node is a portable terminal device. Some or all of the router nodes
That the water level detection means is provided with second abnormality notification means for notifying the surroundings of the occurrence of the abnormal water level by voice or display when the water level detection information in which a value indicating water level detection is generated is generated; The abnormal water level notification system according to any one of claims 1 to 9, which is characterized.