JP2008051541A - Typhoon center detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To determine accurately the center position of a typhoon, even when a non-rain band domain of a clear circular domain or elliptic domain does not exist near the center of the typhoon, or when the maximum/minimum Doppler velocity cannot be detected because a distribution of a rain belt has deviation. <P>SOLUTION: This device is provided with an equal Doppler velocity line formation part 12 for forming an equal Doppler velocity line by connecting one or more equal Doppler velocity domains having a prescribed Doppler velocity value, and an equal Doppler velocity line convergence degree calculation part 13 for calculating the convergence degree of the equal Doppler velocity lines formed by the equal Doppler velocity line formation part 12. The center position of the typhoon is detected from the convergence degree of the equal Doppler velocity lines calculated by the equal Doppler velocity line convergence degree calculation part 13. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a typhoon center detection device that detects the center position of a typhoon.

Conventional typhoon center detection devices use a detection method that utilizes the presence of a closed circular area or elliptical area having no rain band at the center of the typhoon.
That is, the conventional typhoon center detection device, for example, divides a weather satellite image or a radar image into a portion having a typhoon rain zone and a portion having no typhoon rain zone, and searches for a closed circular region or an elliptic region without the rain zone. The center position of the typhoon is detected by obtaining the center of the circular area or the elliptical area (see, for example, Patent Document 1).
However, this detection method is based on the premise that there is a rain zone having a clear circular region or an elliptical non-rain region near the center of the typhoon, so a clear circular region or elliptic region near the center of the typhoon. If there is no non-rainfall area, it is difficult to accurately determine the center position of the typhoon.

In addition to the above typhoon center detection device, in the typhoon region, it is assumed that the wind field is axially symmetric with respect to the typhoon center position, and the detection method for obtaining the center position from the Doppler velocity distribution using the Doppler radar observations A typhoon center detection apparatus using a cypress has been developed (see, for example, Non-Patent Document 1).
However, since this detection method is based on the premise that a rain band having the maximum / minimum Doppler speed is observed, the distribution of the rain band is biased, and the maximum / minimum Doppler speed cannot be detected. Therefore, it is difficult to accurately determine the center position of the typhoon.

In general, the Doppler speed during a typhoon is larger than the Doppler speed during normal times, and the Doppler speed turns up in a weather Doppler radar having a wavelength of 3 cm to 10 cm for observing normal precipitation particles.
For example, in a radar having a transmission frequency of 5 GHz (C band, wavelength of about 6 cm) and a pulse repetition frequency of 260 Hz, aliasing occurs at a Doppler speed of +3.9 m / s or more and a Doppler speed of -3.9 m / s or less. Since the Doppler speed during a typhoon is several tens of m / s, it is necessary to correct folding.
Therefore, when the Doppler speed loopback correction is not properly performed, the detection accuracy of the center position of the typhoon deteriorates.

JP 2000-98055 A (paragraph numbers [0018] to [0023], FIG. 1) V. T.A. Wood "A technical for detecting a tropical cyclone center using a Doppler radar" J. Atmos. Oceanic Technol. 11, 1207-1216.

Since the conventional typhoon center detection device is configured as described above, when there is no clear circular area or elliptical non-rainfall area near the center of the typhoon, or when the distribution of rainfall bands is uneven, / When the minimum Doppler speed cannot be detected, there is a problem that it is difficult to accurately determine the center position of the typhoon.
In addition, when the Doppler speed return correction is not appropriately performed, there is a problem that the detection accuracy of the center position of the typhoon is deteriorated.

  The present invention has been made to solve the above-described problems.There is no clear circular region or elliptical non-rainfall region near the center of the typhoon, or there is a bias in the rainband distribution. An object of the present invention is to obtain a typhoon center detection device that can accurately determine the center position of a typhoon even when the maximum / minimum Doppler speed cannot be detected.

  The typhoon center detecting device according to the present invention includes an equal Doppler velocity line forming unit that connects one or more equal Doppler velocity regions having a predetermined Doppler velocity value to form an equal Doppler velocity line, and the equal Doppler velocity line forming unit. And a convergence degree calculating means for calculating the convergence degree of the equal Doppler velocity line formed by the method, and detecting the center position of the typhoon from the convergence degree of the equal Doppler velocity line calculated by the convergence degree calculating means. It is.

  According to the present invention, an equal Doppler velocity line forming unit that connects one or more equal Doppler velocity regions having a predetermined Doppler velocity value to form an equal Doppler velocity line, and the equal Doppler velocity line forming unit. Convergence degree calculating means for calculating the convergence degree of the equal Doppler velocity line is provided, and the center position of the typhoon is detected from the convergence degree of the equal Doppler velocity line calculated by the convergence degree calculating means. The center of the typhoon is accurate even when there is no clear circular or elliptical non-rainfall area near the center, or when the maximum / minimum Doppler velocity cannot be detected due to the uneven distribution of the rainband. There is an effect that the position can be obtained.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a typhoon center detection apparatus according to Embodiment 1 of the present invention. In the figure, a Doppler velocity distribution measuring unit 1 is constituted by, for example, a Doppler radar, and radiates electromagnetic waves in the atmosphere. A process for measuring the Doppler velocity distribution of precipitation particles in the observation region is performed by receiving electromagnetic waves reflected by the precipitation particles in the observation region. The Doppler velocity distribution measuring unit 1 constitutes Doppler velocity distribution measuring means.

The typhoon center detection unit 2 includes an equal Doppler velocity region extraction unit 11, an equal Doppler velocity line formation unit 12, an equal Doppler velocity line convergence calculation unit 13, and a center position detection unit 14. A process for detecting the center position of the typhoon from the measured Doppler velocity distribution is performed.
The display unit 3 is a display device such as a display that displays the center position of the typhoon detected by the typhoon center detection unit 2.

The equal Doppler velocity region extraction unit 11 of the typhoon center detection unit 2 accepts the setting of the Doppler velocity value of the equal Doppler velocity region to be extracted, and the Doppler velocity value is calculated from the Doppler velocity distribution measured by the Doppler velocity distribution measurement unit 1. A process of extracting an equal Doppler velocity region having The equal Doppler velocity region extraction unit 11 constitutes an equal Doppler velocity region extraction means.
The equal Doppler velocity line forming unit 12 of the typhoon center detection unit 2 connects the equal Doppler velocity regions spatially adjacent to each other among one or more equal Doppler velocity regions extracted by the equal Doppler velocity region extraction unit 11, Alternatively, a process of forming equal Doppler velocity lines by connecting equal Doppler velocity regions within a predetermined distance is performed. The equal Doppler velocity line forming unit 12 constitutes an equal Doppler velocity line forming unit.

The equal Doppler velocity line convergence calculation unit 13 of the typhoon center detection unit 2 calculates the convergence of the equal Doppler velocity line formed by the equal Doppler velocity line formation unit 12 (spatial density of the equal Doppler velocity line). To implement. The equal Doppler velocity line convergence calculation unit 13 constitutes a convergence calculation unit.
The center position detection unit 14 of the typhoon center detection unit 2 searches for a position with the highest degree of convergence of the equal Doppler velocity line calculated by the equal Doppler velocity line convergence degree calculation unit 13, and determines the position with the highest degree of convergence as the center of the typhoon. Processing to output the position to the display unit 3 is performed. The center position detector 14 constitutes a center position detector.
FIG. 9 is a flowchart showing the processing contents of the typhoon center detection apparatus according to Embodiment 1 of the present invention.

Next, the operation will be described.
The Doppler velocity distribution measurement unit 1 radiates electromagnetic waves into the atmosphere and receives the electromagnetic waves reflected by the precipitation particles in the observation region (step ST1), thereby measuring the Doppler velocity distribution of the precipitation particles in the observation region ( Step ST2).
Here, the calculation process of the Doppler velocity of precipitation particles is a known technique. For example, when an electromagnetic wave reflected by precipitation particles is received, the Doppler frequency of the received signal is calculated, and the Doppler frequency is converted to the Doppler velocity. By doing so, the Doppler velocity of precipitation particles can be obtained.

Specifically, the Doppler velocity distribution of precipitation particles in the observation area is measured as follows.
The Doppler velocity distribution measuring unit 1 observes a plurality of received signal samples for each distance by transmitting an electromagnetic wave a plurality of times in the direction in which the beam is directed using an antenna.
When the Doppler velocity distribution measuring unit 1 observes a plurality of received signal samples for each distance, the Doppler velocity distribution measuring unit 1 performs Fourier transform on these received signal samples and calculates the power at each frequency point, thereby calculating the power spectrum of the received signal. Ask.
When obtaining the power spectrum of the received signal, the Doppler velocity distribution measuring unit 1 calculates the Doppler velocity V _D of precipitation particles assuming that the frequency having the peak of the power spectrum is the Doppler frequency f _D as shown below. .
V _D = f _D λ / 2
Where λ is the wavelength of the electromagnetic wave transmitted from the Doppler velocity distribution measuring unit 1.

Thus, since the Doppler velocity distribution measuring unit 1 calculates the Doppler velocity V _D of precipitation particles for each distance, a distance distribution of the Doppler velocity in the beam pointing direction of the antenna is obtained.
Therefore, if the Doppler velocity distribution measuring unit 1 changes the direction of the antenna and repeats the same observation, a distance distribution of the Doppler velocity is obtained in each direction, and finally a spatial distribution of the Doppler velocity is obtained.
Note that a method for calculating the Doppler velocity is disclosed in, for example, the following non-patent documents.
Non-patent literature: Doviak and Zrnic, Doppler Radar and Weather Observers, Second Edition, Academic Press, Inc. 1993.

In the first embodiment, for simplification of description, the wind speed distribution of the typhoon is assumed to be axially symmetric as in Non-Patent Document 1 described above.
FIG. 10 is an explanatory diagram showing the wind speed distribution simulating a typhoon with arrows.
In the figure, the direction of the arrow represents the wind direction, and the length of the arrow represents the wind speed.
In the example of FIG. 10, the center position of the typhoon is a position where the horizontal axis is “40” and the vertical axis is “30”, the rhombus whose horizontal axis is “0” and whose vertical axis is “0” is Doppler. It represents the position of the radar.
In the typhoon wind speed distribution of FIG. 10, the wind speed value in the tangential direction is the highest on the circumference of the radius 10 from the center position (assuming the core of the typhoon), and the wind speed becomes smaller toward the inside and outside than that. Yes.

FIG. 11 is an explanatory diagram showing the Doppler velocity distribution when the typhoon of FIG. 10 is observed, and FIG. 11 shows the Doppler velocity measurement values displayed in shades. However, this measured value is returned at a certain Doppler speed Vr. The Doppler speed of -Vr for the white area and + Vr for the black area is obtained. Actually, a Doppler velocity larger than + Vr or a Doppler velocity smaller than −Vr is a true value, but the measured value of the Doppler velocity is turned back by aliasing, and only the Doppler velocity in the range of −Vr to + Vr is measured. Has been obtained.
As shown in FIG. 11, the equal Doppler lines converge at the position of the Doppler radar and the center position of the typhoon.

The equal Doppler velocity region extraction unit 11 of the typhoon center detection unit 2 uses the Doppler velocity value set in advance (Step ST3), and has the Doppler velocity value from the Doppler velocity distribution measured by the Doppler velocity distribution measurement unit 1. An equal Doppler velocity region is extracted (step ST4).
A plurality of values may be used as the Doppler velocity value set for extracting the equal Doppler velocity region. For example, an equal Doppler velocity region having three types of Doppler velocity values such as −5 m / s, 0 m / s, and 5 m / s may be extracted.
Hereinafter, the process of extracting the equal Doppler velocity region in the equal Doppler velocity region extracting unit 11 will be specifically described.
Here, for convenience of explanation, it is assumed that the Doppler velocity measured by the Doppler velocity distribution measuring unit 1 is divided by a 4 × 4 two-dimensional mesh as shown in FIG.
The numbers in each mesh in FIG. 12 represent the Doppler speed.

For example, when the Doppler velocity region extraction unit 11 is set to extract a Doppler velocity region having a Doppler velocity value of 0 m / s or in a range of −0.1 to 0.1 m / s, the Doppler velocity is as follows. Compare the set value and the Doppler velocity distribution in each mesh.
The arrow in the upper diagram of FIG. 13 indicates the order of mesh comparison, and shows the state of comparison from the upper left mesh to the lower right mesh in order.
When the Doppler velocity distribution of the mesh is 0 m / s or in the range of −0.1 to 0.1 m / s, the equal Doppler velocity region extraction unit 11 is “1” as shown in the lower diagram of FIG. A sign is attached, otherwise, a sign of “0” is attached.
Then, the equal Doppler velocity region extraction unit 11 extracts the mesh region labeled “1” as being an equal Doppler velocity region.

When the equal Doppler velocity region extraction unit 11 extracts the equal Doppler velocity region, the equal Doppler velocity region forming unit 12 of the typhoon center detection unit 2 extracts one or more equal Doppler velocity region extracted by the equal Doppler velocity region extraction unit 11. Among them, equal Doppler velocity regions that are spatially adjacent to each other are connected to each other, or equal Doppler velocity regions that are within a predetermined distance are connected to form an equal Doppler velocity line (step T5).
Hereinafter, the process of forming an equal Doppler velocity line in the equal Doppler velocity line forming unit 12 will be specifically described.
Here, for convenience of explanation, as shown in FIG. 14, it is assumed that there are eight meshes (hereinafter referred to as “target meshes”) diagonally in front, rear, left, and right of the target mesh.

The equal Doppler velocity line forming unit 12 searches for a target mesh having a mesh with a symbol “1” among the eight target meshes.
For example, among the eight target meshes, the target mesh of (1), the target mesh of (5), and the target mesh of (9) may have meshes with a sign of “1”. For example, by connecting the target mesh of (1), the target mesh of (5), and the mesh with the symbol “1” included in the target mesh of (9), an equal Doppler velocity line is obtained. (Connecting line) is formed.
In this case, the thickness of the equal Doppler velocity line is one mesh. For example, if the velocity range for extracting the equal Doppler velocity line is widened to −5 m / s to +5 m / s, the thickness for a plurality of meshes. An iso-Doppler velocity line with is extracted.

When the equal Doppler velocity line forming unit 12 forms an equal Doppler velocity line, the equal Doppler velocity line convergence calculation unit 13 of the typhoon center detection unit 2 converges at a certain point or the convergence degree of the equal Doppler velocity line in a small region (etc. A spatial density of Doppler velocity lines is calculated (step ST6).
That is, the equal Doppler velocity line convergence degree calculation unit 13 can determine whether or not it is converged by examining the number of equal Doppler velocity lines included in a certain range. The convergence degree of the equal Doppler velocity line in the target mesh is obtained by examining the number of equal Doppler velocity lines included in the mesh.

Further, the degree of convergence of the equal Doppler velocity line can be defined, for example, by the ratio (area) of the equal Doppler velocity region in a certain predetermined region (area).
This is because, in the vicinity of the center position of the typhoon, the equal Doppler velocity lines are dense, and the proportion of the equal Doppler velocity region in a given region increases.

Further, the degree of convergence of the equal Doppler velocity line can be defined by, for example, a certain point or the number of connected equal Doppler velocity lines in a small region.
This is because the equal Doppler velocity line converges at the position of the Doppler radar and the center position of the typhoon, and the number of connections of the equal Doppler velocity line becomes high at the two points.
Generally, the Doppler radar value and the typhoon center position have higher Doppler velocity values near the typhoon center position, and therefore the number of connections at the typhoon center position is higher.
FIG. 15 is an explanatory diagram schematically showing the definition of the degree of convergence based on the number of connections. In the figure, 101 to 105 are equal Doppler velocity lines.
Assume that the small area is set to the rectangular area 106. At this time, five equal Doppler velocity lines are connected to the rectangular area 106, that is, the number of connections is five.
On the other hand, when the small area is set to the rectangular area 107, the only Doppler velocity line connected to the rectangular area 107 is 102, and the number of connections is two.
The number of connections increases in the region where the equal Doppler velocity line converges. Therefore, the number of connections can be defined as a value representing the degree of convergence.

In addition, the degree of convergence of the equal Doppler velocity line can be defined by, for example, the curvature of the equal Doppler velocity line included in a certain predetermined region.
In the vicinity of the center position of the typhoon where the iso-Doppler velocity lines are concentrated, as shown in FIG. 11, the iso-Doppler velocity lines are distributed concentrically, so that the curvature is higher than that of the other regions. Because.

The center position detection unit 14 of the typhoon center detection unit 2 has the maximum convergence degree of the equal Doppler velocity line other than the position of the Doppler radar when the equal Doppler velocity line convergence degree calculation unit 13 calculates the convergence degree of the equal Doppler velocity line. Is searched (step ST7).
When the center position detection unit 14 searches for a position where the convergence degree of the iso-Doppler velocity line is maximum, the center position detection unit 14 recognizes that the position having the maximum convergence degree is the center position of the typhoon, and displays the center position of the typhoon on the display unit 3. Output.
When the display unit 3 receives the typhoon center position from the typhoon center detection unit 2, the display unit 3 displays the typhoon center position on the display (step ST8).

  As is apparent from the above, according to the first embodiment, an equal Doppler velocity line forming unit 12 that forms an equal Doppler velocity line by connecting one or more equal Doppler velocity regions having a predetermined Doppler velocity value; An equal Doppler velocity line convergence degree calculation unit 13 that calculates the convergence degree of the equal Doppler velocity line formed by the equal Doppler velocity line formation unit 12 is provided, and is calculated by the equal Doppler velocity line convergence degree calculation unit 13. Since the center position of the typhoon is detected from the convergence degree of the Doppler velocity line, there is no clear circular area or elliptical non-rainfall area near the center of the typhoon, or there is a bias in the distribution of the rainband. Even when the maximum / minimum Doppler speed cannot be detected, the center position of the typhoon can be obtained with high accuracy.

That is, according to the first embodiment, since the position where the convergence degree of the iso-Doppler velocity line is the maximum is detected as the center position of the typhoon, for example, the typhoon precipitation region is spatially located near the typhoon center position. Even if it is uniformly distributed and the rain zone is not clear, the center position of the typhoon can be detected appropriately.
Further, according to the first embodiment, since the center position of the typhoon is detected based on the convergence degree of the equal Doppler velocity line and the detection performance does not depend on the Doppler velocity value, for example, the typhoon wind velocity can be observed by the radar. The center position of the typhoon can be detected without performing the folding correction even when the folding speed exceeds the Doppler speed.

Embodiment 2. FIG.
FIG. 2 is a block diagram showing a typhoon center detection apparatus according to Embodiment 2 of the present invention. In the figure, the same reference numerals as those in FIG.
The equal Doppler velocity line extension unit 15 performs a process of extending the equal Doppler velocity line formed by the equal Doppler velocity line forming unit 12.
The equal Doppler velocity line convergence degree calculation unit 16 performs a process of calculating the convergence degree of the extension destination of the equal Doppler velocity line extended by the equal Doppler velocity line extension unit 15.
The equal Doppler velocity line extension unit 15 and the equal Doppler velocity line convergence calculation unit 16 constitute a convergence calculation means.

In the first embodiment, the equal Doppler velocity line convergence degree calculation unit 13 of the typhoon center detection unit 2 calculates the convergence degree of the equal Doppler velocity line formed by the equal Doppler velocity line formation unit 12. When the rain region (rain area) is spatially small, the detection accuracy of the center position of the typhoon may be slightly deteriorated.
Therefore, in the second embodiment, when the rainfall region (rainband area) is spatially small, the equal Doppler velocity line extension unit 15 of the typhoon center detection unit 2 is formed by the equal Doppler velocity line formation unit 12. The equal Doppler velocity line is extended while maintaining the curvature, and the equal Doppler velocity line convergence calculation unit 16 calculates the convergence of the extended equal Doppler velocity line.
As a result, even when the rain region (rain area) is spatially small, the convergence level of the Doppler velocity line passing through the center position of the typhoon can be obtained, so that the center position of the typhoon can be detected with high accuracy. There is an effect that can be done.

Embodiment 3 FIG.
FIG. 3 is a block diagram showing a typhoon center detection apparatus according to Embodiment 3 of the present invention. In the figure, the same reference numerals as those in FIG.
The 0 Doppler velocity region extraction unit 11a of the typhoon center detection unit 2 is an equal Doppler velocity region having a Doppler velocity value of “0” from the Doppler velocity distribution measured by the Doppler velocity distribution measuring unit 1 (hereinafter referred to as “0 Doppler velocity region”). (Referred to as ")". The 0 Doppler velocity region extracting unit 11a constitutes an equal Doppler velocity region extracting means.
The 0 Doppler velocity line forming unit 12a of the typhoon center detecting unit 2 connects 0 Doppler velocity regions that are spatially adjacent to each other among one or more 0 Doppler velocity regions extracted by the 0 Doppler velocity region extracting unit 11a. Alternatively, a process of forming 0 Doppler velocity lines by connecting the 0 Doppler velocity regions within a predetermined distance is performed. The 0 Doppler velocity line forming unit 12a constitutes an equal Doppler velocity line forming unit.

The 0 Doppler velocity line convergence calculation unit 13a of the typhoon center detection unit 2 calculates the convergence of the 0 Doppler velocity line formed by the 0 Doppler velocity line formation unit 12a (spatial density of the 0 Doppler velocity line). To implement. The 0 Doppler velocity line convergence degree calculation unit 13a constitutes a convergence degree calculation unit.
The center position detection unit 14a of the typhoon center detection unit 2 searches for the position with the highest convergence of the 0 Doppler velocity line calculated by the 0 Doppler velocity line convergence calculation unit 13a, and determines the position with the highest convergence as the center of the typhoon. Processing to output the position to the display unit 3 is performed. The center position detector 14a constitutes a center position detector.

Next, the operation will be described.
In the first embodiment, the equal Doppler velocity region extraction unit 11 of the typhoon center detection unit 2 accepts the setting of the Doppler velocity value of the equal Doppler velocity region to be extracted, and the Doppler measured by the Doppler velocity distribution measurement unit 1. Although an example in which an equal Doppler velocity region having the Doppler velocity value is extracted from the velocity distribution has been shown, the Doppler velocity value is “0” in the Doppler velocity folding region, and therefore, the 0 Doppler velocity region of the typhoon center detection unit 2 The extraction unit 11 a may extract a 0 Doppler velocity region having a Doppler velocity value of “0” from the Doppler velocity distribution measured by the Doppler velocity distribution measurement unit 1.
Specifically, it is as follows.

When the Doppler velocity distribution measurement unit 1 measures the Doppler velocity distribution, the 0 Doppler velocity region extraction unit 11a of the typhoon center detection unit 2 performs a Doppler velocity of “0” from the Doppler velocity distribution. A 0 Doppler velocity region having a value is extracted.
The extraction processing of the 0 Doppler velocity region in the 0 Doppler velocity region extraction unit 11a is the same as the extraction processing of the equal Doppler velocity region in the equal Doppler velocity region extraction unit 11 except that the Doppler velocity value of the extraction target region is different. Therefore, detailed description is omitted.

When the 0 Doppler velocity region extraction unit 11a extracts the 0 Doppler velocity region, the 0 Doppler velocity line forming unit 12a of the typhoon center detection unit 2 extracts one or more 0 Doppler velocity regions extracted by the 0 Doppler velocity region extraction unit 11a. Among them, the 0 Doppler velocity regions that are spatially adjacent to each other are connected, or the 0 Doppler velocity regions within a predetermined distance are connected to form a 0 Doppler velocity line.
The 0 Doppler velocity line forming process in the 0 Doppler velocity line forming unit 12a is the same as the forming process of the equal Doppler velocity line in the equal Doppler velocity line forming unit 12 except that the Doppler velocity value of the connection target region is different. Therefore, detailed description is omitted.

The 0 Doppler velocity line convergence calculation unit 13a of the typhoon center detection unit 2 calculates the convergence of the 0 Doppler velocity line at a certain point or a small region when the 0 Doppler velocity line formation unit 12a forms the 0 Doppler velocity line. To do.
The convergence calculation processing in the 0 Doppler velocity line convergence calculation unit 13a is different only in that the Doppler velocity line to be calculated is a 0 Doppler velocity line, and the convergence calculation processing in the equal Doppler velocity line convergence calculation unit 13 is performed. Therefore, detailed description is omitted.

The center position detection unit 14a of the typhoon center detection unit 2 has the highest convergence of the 0 Doppler velocity line other than the position of the Doppler radar when the 0 Doppler velocity line convergence calculation unit 13a calculates the convergence of the 0 Doppler velocity line. Search for a higher position.
When the center position detection unit 14a searches for a position where the convergence degree of the 0 Doppler velocity line is maximum, the center position detection part 14a recognizes that the position having the maximum convergence degree is the center position of the typhoon, and displays the center position of the typhoon on the display unit 3. Output.
When the display unit 3 receives the typhoon center position from the typhoon center detection unit 2, the display unit 3 displays the typhoon center position on the display.

  As is apparent from the above, according to the third embodiment, a 0 Doppler velocity region having a Doppler velocity value of “0” is extracted from the Doppler velocity distribution measured by the Doppler velocity distribution measuring unit 1. Therefore, unlike the equal Doppler velocity region extraction unit 11 in FIG. 1, the center position of the typhoon can be detected without accepting the setting of the Doppler velocity value of the equal Doppler velocity region to be extracted.

Embodiment 4 FIG.
4 is a block diagram showing a typhoon center detection apparatus according to Embodiment 4 of the present invention. In the figure, the same reference numerals as those in FIG.
The 0 Doppler velocity line extension portion 15a performs a process of extending the 0 Doppler velocity line formed by the 0 Doppler velocity line forming portion 12a.
The 0 Doppler velocity line convergence degree calculation unit 16a performs a process of calculating the convergence degree of the extension destination of the 0 Doppler velocity line extended by the 0 Doppler velocity line extension unit 15a.
The 0 Doppler velocity line extension 15a and the 0 Doppler velocity line convergence calculation unit 16a constitute a convergence calculation means.

In the third embodiment, the 0 Doppler velocity line convergence calculation unit 13a of the typhoon center detection unit 2 calculates the convergence of the 0 Doppler velocity line formed by the 0 Doppler velocity line formation unit 12a. When the rain region (rain area) is spatially small, the detection accuracy of the center position of the typhoon may be slightly deteriorated.
Therefore, in the fourth embodiment, when the rain region (rain area) is spatially small, the 0 Doppler velocity line extension 15a of the typhoon center detection unit 2 is formed by the 0 Doppler velocity line forming unit 12a. The zero Doppler velocity line is extended while maintaining the curvature, and the zero Doppler velocity line convergence degree calculation unit 16a calculates the convergence degree of the extension zero Doppler velocity line.
This makes it possible to obtain the convergence level of the 0 Doppler velocity line passing through the center position of the typhoon even when the rain region (rain area) is spatially small, so that the center position of the typhoon can be detected with high accuracy. There is an effect that can be done.

Embodiment 5. FIG.
FIG. 5 is a block diagram showing a typhoon center detecting apparatus according to Embodiment 5 of the present invention. In the figure, the same reference numerals as those in FIG.
The observation region limiting unit 4 includes a 0 Doppler velocity region extraction unit 21, a 0 Doppler velocity line formation unit 22, a straight line detection unit 23, and a buffer unit 25, and limits the observation region when detecting the center position of the typhoon. Perform the process. Note that the observation region limiting unit 4 constitutes observation region limiting means.
The 0 Doppler velocity region extraction unit 21 of the observation region limiting unit 4 performs a process of extracting a 0 Doppler velocity region having a Doppler velocity value of “0” from the Doppler velocity distribution measured by the Doppler velocity distribution measurement unit 1.

The 0 Doppler velocity line forming unit 22 of the observation region limiting unit 4 connects spatially adjacent 0 Doppler velocity regions among one or more 0 Doppler velocity regions extracted by the 0 Doppler velocity region extracting unit 21, Alternatively, a process of forming 0 Doppler velocity lines by connecting the 0 Doppler velocity regions within a predetermined distance is performed.
The straight line detection unit 23 of the observation area limiting unit 4 detects a 0 Doppler velocity line that can be regarded as a straight line from one or more 0 Doppler velocity lines formed by the 0 Doppler velocity line forming unit 22 and performs a typhoon center detection process. The region is limited to the peripheral region of the 0 Doppler velocity line.
The buffer unit 25 of the observation area limiting unit 4 inputs the equal Doppler velocity line (straight line) output from the straight line detection unit 23 and the Doppler velocity distribution measured by the Doppler velocity distribution measuring unit 1, and the equal Doppler velocity line ( Straight line) and the Doppler velocity distribution are output to the typhoon center detection unit 2.

Next, the operation will be described.
Since the wind speed of the typhoon has a distribution as shown in FIG. 10, in the Doppler speed distribution observed by the Doppler radar, the Doppler speed on the line connecting the position of the Doppler radar and the center position of the typhoon is almost zero.
The other 0 Doppler velocity lines are curves having a certain curvature. Therefore, the 0 Doppler velocity line that can be regarded as a substantially straight line extending from the position of the Doppler radar passes through the center position of the typhoon.
Therefore, in the fifth embodiment, the observation range is limited to the vicinity of the 0 Doppler velocity line that can be regarded as a substantially straight line, thereby reducing the amount of calculation and reducing erroneous detection of the center position of the typhoon.
Specifically, it is as follows.

When the Doppler velocity distribution measurement unit 1 measures the Doppler velocity distribution, the 0 Doppler velocity region extraction unit 11a of FIG. Similarly, a 0 Doppler velocity region having a Doppler velocity value of “0” is extracted from the Doppler velocity distribution.
When the 0 Doppler velocity region extracting unit 21 extracts the 0 Doppler velocity region, the 0 Doppler velocity line forming unit 22 of the observation region limiting unit 4 extracts the 0 Doppler velocity region similarly to the 0 Doppler velocity line forming unit 12a of FIG. Of the one or more 0 Doppler velocity regions extracted by the unit 21, the 0 Doppler velocity regions that are spatially adjacent to each other are connected, or the 0 Doppler velocity regions that are within a predetermined distance are connected to each other. Form a Doppler velocity line.

When the 0 Doppler velocity line forming unit 22 forms a 0 Doppler velocity line, the straight line detection unit 23 of the observation region limiting unit 4 is a straight line among one or more 0 Doppler velocity lines formed by the 0 Doppler velocity line forming unit 22. In this case, only the 0 Doppler velocity line whose straight line passes through the radar position or the vicinity thereof is detected, and the observation area is limited to the peripheral area of the 0 Doppler velocity line.
When the buffer unit 25 of the observation area limiting unit 4 receives the equal Doppler velocity line (straight line) from the straight line detection unit 23 and receives the Doppler velocity distribution from the Doppler velocity distribution measurement unit 1, the buffer unit 25 receives the equal Doppler velocity line (straight line) and the Doppler. The velocity distribution is output to the typhoon center detection unit 2.
Thereby, the equal Doppler velocity region extraction unit 11 (or the 0 Doppler velocity region extraction unit 11a) of the typhoon center detection unit 2 includes the observation region limiting unit 4 in the Doppler velocity distribution measured by the Doppler velocity distribution measurement unit 1. An equal Doppler velocity region (or 0 Doppler velocity region) is extracted from the Doppler velocity distribution in the observation region limited by the straight line detection unit 23.
The other processing contents of the typhoon center detection unit 2 are the same as those in the first to fourth embodiments, and thus detailed description thereof is omitted.

  In the above description of the embodiment, the region is limited using a 0 Doppler velocity line that can be regarded as a straight line. However, if it is not limited to a complete straight line, even if it is not a 0 Doppler speed line, another Doppler speed value may be set to extract an equal Doppler speed line to limit the area. This is because, as can be seen from FIG. 11, the equal Doppler velocity line in the vicinity of the straight line connecting the radar position and the typhoon center has a shape close to a straight line even if the Doppler velocity value deviates from zero. .

In FIG. 5, the observation region limiting unit 4 is arranged in front of the typhoon center detection unit 2. However, as shown in FIG. 16, the observation region limitation unit 4 is arranged in the middle of the typhoon center detection unit 2. You may make it arrange | position to.
In this case, the equal Doppler velocity region extracting unit 11 and the equal Doppler velocity line forming unit 12 of the typhoon center detecting unit 2 also serve as the 0 Doppler velocity region extracting unit 21 and the 0 Doppler velocity line forming unit 22 of the observation region limiting unit 4. Therefore, the 0 Doppler velocity region extracting unit 21 and the 0 Doppler velocity line forming unit 22 of the observation region limiting unit 4 can be omitted to simplify the configuration.
However, in FIG. 16, the buffer unit 26 of the observation region limiting unit 4 inputs the equal Doppler velocity line (straight line) output from the straight line detection unit 23 and the equal Doppler velocity line formed by the equal Doppler velocity line forming unit 12. Then, a process of outputting these to the equal Doppler velocity convergence calculation unit 13 is performed.

Embodiment 6 FIG.
FIG. 6 is a block diagram showing a typhoon center detection apparatus according to Embodiment 6 of the present invention. In the figure, the same reference numerals as those in FIG.
The straight line extension unit 24 of the observation area limiting unit 4 extends the equal Doppler velocity line that can be regarded as a straight line detected by the straight line detection unit 23, and performs processing for limiting the observation region to the peripheral region of the destination equal Doppler velocity line. .
The buffer unit 27 of the observation area limiting unit 4 receives the extended Doppler velocity line (straight line) output from the linear extension unit 24 and the Doppler velocity distribution measured by the Doppler velocity distribution measurement unit 1, and inputs the extended destination Doppler velocity distribution. A process of outputting the equal Doppler velocity line (straight line) and the Doppler velocity distribution to the typhoon center detection unit 2 is performed.

In the fifth embodiment, a 0 Doppler velocity line that can be regarded as a straight line is detected from one or more 0 Doppler velocity lines formed by the 0 Doppler velocity line forming unit 22, and the observation region is set around the 0 Doppler velocity line. Although the limitation to the region is shown, when the distribution of the precipitation region in the observation region is small and a sufficient 0 Doppler velocity line cannot be secured, the limitation accuracy of the observation region may deteriorate.
Therefore, in this sixth embodiment, when the distribution of the precipitation region in the observation region is small and a sufficient 0 Doppler velocity line cannot be ensured, the straight line extension unit 24 is the straight line detected by the straight line detection unit 23. The equivalent Doppler velocity line can be extended so that the observation area is limited to the area around the extended equal Doppler velocity line.
As a result, the center position of the typhoon can be detected properly even when the distribution of the precipitation area in the entire observation area is small, especially when there are few precipitation areas in a straight line passing through the center position of the typhoon from the Doppler radar position. Play.

Embodiment 7 FIG.
7 is a block diagram showing a typhoon center detecting apparatus according to Embodiment 7 of the present invention. In the figure, the same reference numerals as those in FIG.
The observation area limiting unit 5 measures the echo intensity distribution in the precipitation area in the observation area, detects the typhoon rain band area from the echo intensity distribution, and limits the observation area of the Doppler velocity distribution measurement unit 1 to the above rain band area. Perform the process. Note that the observation region limiting unit 5 constitutes observation region limiting means.
The echo intensity distribution measuring unit 31 of the observation region limiting unit 5 is configured by, for example, a Doppler radar, and radiates electromagnetic waves into the atmosphere and receives the electromagnetic waves reflected by the precipitation particles in the observation region. Implement a process to measure the echo intensity distribution in the precipitation region.
The typhoon rain zone detection unit 32 of the observation region limiting unit 5 detects the typhoon rain zone region from the echo intensity distribution measured by the echo intensity distribution measurement unit 31, and the observation region of the Doppler velocity distribution measurement unit 1 is used as the rain zone region. The processing limited to is performed.

Next, the operation will be described.
The echo intensity distribution measuring unit 31 of the observation region limiting unit 5 radiates an electromagnetic wave into the atmosphere and receives the electromagnetic wave reflected by the precipitation particles in the observation region, for example, so that the echo intensity distribution of the precipitation region in the observation region is received. Measure.
When the echo intensity distribution measuring unit 31 measures the echo intensity distribution, the typhoon rain band detecting unit 32 of the observation area limiting unit 5 detects a typhoon rain band region from the echo intensity distribution.
As a method for detecting the typhoon rain zone area, for example, as in the technique disclosed in Japanese Patent Application Laid-Open No. 2005-164490, the typhoon rain zone area is regarded as a spiral and a spiral curve is applied, Considering the typhoon rain zone as a circle, a method of fitting the circle can be considered.

When the typhoon rain band detecting unit 32 of the observation area limiting unit 5 detects the typhoon rain band area, it limits the observation area of the Doppler velocity distribution measuring unit 1 to the rain band area.
Thereby, the Doppler velocity distribution measurement unit 1 measures the Doppler velocity distribution of the precipitation particles in the observation region limited by the typhoon rain band detection unit 32 of the observation region limitation unit 5.
Since the subsequent processing is the same as in the first to fourth embodiments, detailed description thereof is omitted.
In the above description of the embodiment, each of the Doppler velocity distribution measuring unit 1 and the echo intensity distribution measuring unit 31 is configured by a Doppler radar. However, in practice, the Doppler velocity distribution measurement unit 1 and the echo intensity distribution measurement unit 31 may simultaneously measure using the same Doppler radar.
That is, the Doppler velocity distribution measuring unit 1 and the echo intensity distribution measuring unit 31 are realized by the same radar apparatus hardware, and have a function of performing signal processing for calculating the Doppler velocity from the received signal from the Doppler velocity distribution measuring unit 1 and the received signal. The echo intensity distribution measuring unit 31 has a function of performing signal processing for calculating echo intensity.

  As is apparent from the above, according to the seventh embodiment, the echo intensity distribution in the precipitation area in the observation area is measured, the typhoon rainfall zone area is detected from the echo intensity distribution, and the Doppler velocity distribution measurement unit 1 Since the observation area is limited to the above-mentioned rain zone area, for example, even when the precipitation area is distributed over a wide spatial range, the observation area is limited and the detection accuracy of the center position of the typhoon is improved. It is possible to increase the amount of calculation and to reduce the amount of calculation.

Embodiment 8 FIG.
FIG. 8 is a block diagram showing a typhoon center detection apparatus according to Embodiment 8 of the present invention. In the figure, the same reference numerals as those in FIG.
The echo intensity distribution measuring unit 41 of the typhoon center detecting unit 2 obtains a convergence area from the convergence degree of the equal Doppler velocity line calculated by the equal Doppler velocity line convergence degree calculating unit 13, and obtains the echo intensity distribution in the peripheral region of the convergence area. Perform the measurement process.
The typhoon rain band detection unit 42 of the typhoon center detection unit 2 performs a process of detecting a typhoon rain band region from the echo intensity distribution measured by the echo intensity distribution measurement unit 41.
The echo intensity distribution measuring unit 41 and the typhoon rain band detecting unit 42 constitute a rain band area detecting means.
The center position detection unit 43 of the typhoon center detection unit 2 performs a process of detecting the center position of the rain band area detected by the typhoon rain band detection unit 42. The center position detector 43 constitutes a center position detector.

Next, the operation will be described.
The echo intensity distribution measurement unit 41 of the typhoon center detection unit 2 performs the equal Doppler velocity line when the equal Doppler velocity line convergence calculation unit 13 calculates the convergence degree of the equal Doppler velocity line in the same manner as in the first embodiment. The convergence area is obtained from the degree of convergence of.
That is, the echo intensity distribution measurement unit 41 extracts a region where the convergence degree of the equal Doppler velocity line calculated by the equal Doppler velocity line convergence calculation unit 13 is high.
When the echo intensity distribution measuring unit 41 obtains the convergence area, the echo intensity distribution measurement unit 41 measures the echo intensity distribution in the peripheral area of the convergence area.

When the echo intensity distribution measurement unit 41 measures the echo intensity distribution in the peripheral region of the convergence area, the typhoon rain band detection unit 42 of the typhoon center detection unit 2 performs the echo in the same manner as the typhoon rain band detection unit 32 of FIG. The typhoon rain zone area is detected from the intensity distribution.
When the typhoon rain band detection unit 42 detects a typhoon rain zone area, the center position detection unit 43 of the typhoon center detection unit 2 recognizes that the center position of the rain band area is the typhoon center position, and the typhoon Is output to the display unit 3.
When the display unit 3 receives the typhoon center position from the typhoon center detection unit 2, the display unit 3 displays the typhoon center position on the display.

  As is apparent from the above, according to the eighth embodiment, the convergence area is obtained from the convergence degree of the equal Doppler velocity line calculated by the equal Doppler velocity line convergence degree calculation unit 13, and the echoes in the peripheral region of the convergence area are obtained. Since the intensity distribution was measured, the typhoon rain zone area was detected from the echo intensity distribution, and the center position of the rain band area was detected.For example, the precipitation area is distributed over a wide spatial range. Even in such a case, it is possible to increase the detection accuracy of the center position of the typhoon by limiting the observation area, and to reduce the amount of calculation of the rain band area detection in the typhoon rain band detection unit 42. .

In the example of FIG. 8, the echo intensity distribution measuring unit 41 is arranged between the equal Doppler velocity line convergence calculation unit 13 and the typhoon rainband detecting unit 42, but as shown in FIG. 17. The echo intensity distribution measurement unit 41a corresponding to the echo intensity distribution measurement unit 41 is arranged at the rear stage of the radar transmission / reception unit 1a, and the echo intensity distribution selection unit 44 is arranged at the rear stage of the equal Doppler velocity line convergence calculation unit 13. It may be.
The echo intensity distribution measuring unit 41a measures the echo intensity distribution from the received signal of the radar transceiver unit 1a, and the echo intensity distribution selecting unit 44 converges the equal Doppler velocity line calculated by the equal Doppler velocity line convergence degree calculating unit 13. When the degree becomes maximum, a process of outputting the echo intensity distribution measured by the echo intensity distribution measuring unit 41a to the typhoon rain band detecting unit 42 is performed.
Further, the radar transmission / reception unit 1a and the Doppler velocity distribution calculation unit 1b are components of the Doppler velocity distribution measurement unit 1 shown in FIG.

It is a block diagram which shows the typhoon center detection apparatus by Embodiment 1 of this invention. It is a block diagram which shows the typhoon center detection apparatus by Embodiment 2 of this invention. It is a block diagram which shows the typhoon center detection apparatus by Embodiment 3 of this invention. It is a block diagram which shows the typhoon center detection apparatus by Embodiment 4 of this invention. It is a block diagram which shows the typhoon center detection apparatus by Embodiment 5 of this invention. It is a block diagram which shows the typhoon center detection apparatus by Embodiment 6 of this invention. It is a block diagram which shows the typhoon center detection apparatus by Embodiment 7 of this invention. It is a block diagram which shows the typhoon center detection apparatus by Embodiment 8 of this invention. It is a flowchart which shows the processing content of the typhoon center detection apparatus by Embodiment 1 of this invention. It is explanatory drawing which represented the wind speed distribution which simulated the typhoon with the arrow. It is explanatory drawing showing the Doppler velocity distribution when the typhoon of FIG. 10 is observed. It is explanatory drawing which shows the Doppler velocity distribution divided | segmented by the 4x4 two-dimensional mesh. It is explanatory drawing which shows the extraction process of an equal Doppler speed area | region. It is explanatory drawing which shows eight object meshes adjacent to the attention mesh. It is explanatory drawing which shows typically the definition of the convergence degree by the number of connection. It is a block diagram which shows the other typhoon center detection apparatus by Embodiment 5 of this invention. It is a block diagram which shows the other typhoon center detection apparatus by Embodiment 8 of this invention.

Explanation of symbols

  1 Doppler velocity distribution measurement unit (Doppler velocity distribution measurement means), 1a radar transmission / reception unit, 1b Doppler velocity distribution calculation unit, 2 typhoon center detection unit, 3 display unit, 4 observation region limitation unit (observation region limitation unit), 5 observation Area limiting unit (observation area limiting unit), 11 equal Doppler velocity region extracting unit (equal Doppler velocity region extracting unit), 11a 0 Doppler velocity region extracting unit (equal Doppler velocity region extracting unit), 12 equal Doppler velocity line forming unit ( Equal Doppler velocity line forming means), 12a 0 Doppler velocity line forming section (equal Doppler velocity line forming means), 13 equal Doppler velocity line convergence degree calculating section (convergence degree calculating means), 13a 0 Doppler velocity line convergence degree calculating section ( Convergence degree calculation means), 14 center position detection section (center position detection means), 14a center position detection section (center position detection means), 15 etc. Doppler Degree line extension part (convergence degree calculation means), 15a 0 Doppler velocity line extension part (convergence degree calculation means), 16 equal Doppler velocity line convergence degree calculation part (convergence degree calculation means), 16a 0 Doppler speed line convergence degree calculation part (Convergence calculation means), 210 Doppler velocity region extraction unit, 220 Doppler velocity line formation unit, 23 straight line detection unit, 24 straight line extension unit, 25, 26, 27 buffer unit, 31 echo intensity distribution measurement unit, 32 typhoon Rain zone detection unit, 41 Echo intensity distribution measurement unit (rain zone area detection unit), 41a Echo intensity distribution measurement unit, 42 Typhoon rain zone detection unit (rain zone area detection unit), 43 Center position detection unit (center position detection unit) 44) Echo intensity distribution selection section.

Claims (11)

  Doppler velocity distribution measuring means for measuring the Doppler velocity distribution of precipitation particles in the observation region, and an equivalent Doppler velocity region having a predetermined Doppler velocity value extracted from the Doppler velocity distribution measured by the Doppler velocity distribution measuring means. An area extraction unit, an equal Doppler velocity line forming unit that connects one or more equal Doppler velocity regions extracted by the equal Doppler velocity region extraction unit to form an equal Doppler velocity line, and an equal Doppler velocity line formation unit. Convergence degree calculating means for calculating the degree of convergence of the formed equal Doppler velocity line, and center position detecting means for detecting the center position of the typhoon from the degree of convergence of the equal Doppler velocity line calculated by the convergence degree calculating means. Typhoon center detector.   2. The typhoon center detection according to claim 1, wherein the convergence degree calculating means extends the equal Doppler velocity line formed by the equal Doppler velocity line forming means and calculates the convergence degree of the extended equal Doppler velocity line. apparatus.   The typhoon center detecting device according to claim 1 or 2, wherein the equal Doppler velocity region extracting means extracts an equal Doppler velocity region having a zero Doppler velocity value.   An equal Doppler velocity region having a predetermined Doppler velocity value is extracted from the Doppler velocity distribution measured by the Doppler velocity distribution measuring means, and one or more equal Doppler velocity regions are connected to form one or more equal Doppler velocity lines. An equality Doppler velocity line extraction means is provided that detects an equal Doppler velocity line that can be regarded as a straight line from one or more equal Doppler velocity lines and restricts the observation region to the peripheral region of the equal Doppler velocity line. An equal Doppler velocity region having a predetermined Doppler velocity value is extracted from the Doppler velocity distribution in the observation region limited by the observation region limiting unit from the Doppler velocity distribution measured by the Doppler velocity distribution measuring unit. The typhoon center detection apparatus according to any one of claims 1 to 3.   5. The typhoon center detection apparatus according to claim 4, wherein the observation region limiting means extends an equal Doppler velocity line that can be regarded as a straight line, and limits the observation region to a peripheral region of the extended equal Doppler velocity line.   The observation area limiting means detects an equal Doppler velocity line that can be regarded as a straight line, and detects an equal Doppler velocity line or a straight line that extrapolates an equal Doppler velocity line that passes in the vicinity of the radar position. The typhoon center detection apparatus according to claim 4.   Measures the echo intensity distribution of the precipitation area in the observation area, detects the typhoon rain zone area from the echo intensity distribution, and provides observation area limiting means for limiting the observation area of the Doppler velocity distribution measurement means to the rain zone area The typhoon center detection device according to any one of claims 1 to 3, wherein the typhoon center detection device is provided.   Doppler velocity distribution measuring means for measuring the Doppler velocity distribution of precipitation particles in the observation region, and an equivalent Doppler velocity region having a predetermined Doppler velocity value extracted from the Doppler velocity distribution measured by the Doppler velocity distribution measuring means. An area extraction unit, an equal Doppler velocity line forming unit that connects one or more equal Doppler velocity regions extracted by the equal Doppler velocity region extraction unit to form an equal Doppler velocity line, and an equal Doppler velocity line formation unit. Convergence degree calculating means for calculating the convergence degree of the formed equal Doppler velocity line, and a convergence area is determined from the convergence degree of the equal Doppler velocity line calculated by the convergence degree calculating means, and the echo intensity in the peripheral region of the convergence area Rain zone detection means for measuring a distribution and detecting a typhoon rain zone from the echo intensity distribution, and the rain zone Typhoon center detecting apparatus and a center position detecting means for detecting a center position of the detected rain zones by frequency detection means.   The typhoon center detection according to any one of claims 1 to 8, wherein the convergence calculation means calculates a convergence of an equal Doppler velocity line from a ratio of an equal Doppler velocity region in a predetermined region. apparatus.   The typhoon center according to any one of claims 1 to 8, wherein the convergence calculation means calculates the convergence of the equal Doppler velocity line from the number of connected equal Doppler velocity regions at a predetermined point. Detection device.   The typhoon center detection device according to any one of claims 1 to 8, wherein the convergence degree calculating means calculates the convergence degree of the equal Doppler velocity line from the curvature of the equal Doppler velocity line.

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