CN101246077A - Insulating tube water channel leak detecting method - Google Patents

Insulating tube water channel leak detecting method Download PDF

Info

Publication number
CN101246077A
CN101246077A CNA2007101276729A CN200710127672A CN101246077A CN 101246077 A CN101246077 A CN 101246077A CN A2007101276729 A CNA2007101276729 A CN A2007101276729A CN 200710127672 A CN200710127672 A CN 200710127672A CN 101246077 A CN101246077 A CN 101246077A
Authority
CN
China
Prior art keywords
probe
water
earth
insulating tube
water channel
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CNA2007101276729A
Other languages
Chinese (zh)
Inventor
陈宜中
傅雅芬
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to CNA2007101276729A priority Critical patent/CN101246077A/en
Publication of CN101246077A publication Critical patent/CN101246077A/en
Pending legal-status Critical Current

Links

Images

Abstract

An insulating tube leakage detecting method is a method for detecting the leakage of the insulating tube water channel with embedding earth comprising the wet earth. In the method a detecting instrument with an earth return is included, the detecting instrument is connected to the probe head comprising a water-contacting contact, the probe is arranged in the water channel of the insulating tube, and the invention is characterized in that the water leaking signal of the insulating pipeline is realized by the earth resistance variate of the probe head in the detecting tube. If the water channel of the insulating tube of an area does not have water linkage, then a comparatively stable hydroelectricity resistance value exists between the probe in the insulating pipeline of the area and the earth conducting pipeline, when water linkage occurs in the area the probe in the pipeline will form a returning conduction with shorter distance through the water leakage, therefore the earth resistance value of the probe is diminished correspondingly, and the magnitude of the electric quantity value can reflect whether the water leakage occurs in the area.

Description

Insulating tube water channel leak detecting method
Technical field
A kind of water channel leak detecting method, especially insulating tube water channel leak detecting method.
Background technology
Leak detecting for insulating tube water channel, the method that solves is the same with the plain metal pipeline at present, normally adopt the leakage method of listening, when night, the people was quiet, adopt and listen the leakage device, probe is close on the nearest ground of pipeline, the faint sound wave that leaks is amplified, pass to then in the receiver, the message that makes the people obtain leaking.But this way is known often that having had leaks and is just taked, and generally can often not carry out at ordinary times, does not also have very big assurance even listen to leak, especially the pipeline distance of coming out from water factory is very long, bury very deeply, ground condition complexity is only with listening the leakage method still can not solve seepy question.Our past attempts proposed the patented claim of " non-conductive material water-supply pipeline leak-detection method ", open on March 28th, 2007, application number 200610115384.7, this method adopts more suitable when laying sandstone for the dry loose sandy soil in the north and duct bottom, because the electric conductivity of sandstone is relatively poor relatively, so can carry out according to the embodiment of this patent, it is that electrode with outer many zoness of different that are provided with of water pipe all is inserted in the earth, and take turns to connect electrode, but we are that sandstone soil in drying carries out for the enforcement of beginning, can keep bigger resistance value between the electrode of the outer zones of different of pipe, when leaking like this in inside and outside two interelectrode resistances on the leakage point with the resistance difference of inside and outside two electrodes on leakage point is not bigger, just available its newspaper leakage signal source as the current measuring instrument device; Unsatisfactory when in wetland, implementing afterwards, no longer can keep bigger resistance value between the electrode of the outer zones of different of pipe, in inside and outside two interelectrode resistances on the leakage point with the difference of inside and outside two electrodes on leakage point is just very not little, be difficult to when leaking like this its newspaper leakage signal source as the current measuring instrument device.Leak hunting in order to make the isolated pipe that is embedded in the moist the earth also can carry out instrument, just must improve former patented technology.
Summary of the invention
The objective of the invention is: propose a kind of leak hunting method that comprises the insulating tube water channel of moist the earth with burying underground.
The object of the present invention is achieved like this: it comprises a detector with ground loop, detector connects the probe that has the water receiving contact by termination, probe places insulating tube water channel, and it is characterized in that: the signal that leaks of isolated pipe is to realize by the resistance to earth variable of popping one's head in the detector tube.
Like this, because the earth is the electric loop of detector probe, the insulation water pipe is no matter be embedded in moist the earth or the dry sandstone, if the insulating tube water channel in a zone does not leak, then at the ducted probe of this region insulation with a more constant water power resistance arranged between the conducting pipeline over the ground, this water resistance Inversion that is to say the resistance to earth value of probe, when this zone leaks, probe in the isolated pipe just will be by leaking and the earth returns logical, because it is relative with the distance of scupper nearer to pop one's head in, so the resistance to earth value of probe is also just corresponding less, the size of this charge value can reflect that this zone has or not the generation of leaking, thereby reaches goal of the invention.
Description of drawings
Embodiments of the present invention can have a variety of, and below in conjunction with three embodiment wherein, the present invention is further illustrated.
Fig. 1 is the detection architecture synoptic diagram that leaks of each zone probe electrical communication in pipe in the insulation water pipe.
Fig. 2 is the testing circuit schematic diagram that leaks of each zone probe electrical communication in pipe in the insulation water pipe.
Fig. 3 is the electric detection architecture synoptic diagram that leaks that does not communicate in each zone probe is managed in the insulation water pipe.
Fig. 4 is the flow-type probe detection architecture synoptic diagram that leaks in the insulation water pipe
Embodiment
Among Fig. 11 is ground, the 2nd, and probe, the 3rd, taps, the 4th, power lead, the 5th, detection line, the 6th, tested pipeline, the 7th, the water receiving contact in the probe, the 8th, insulation tube wall, 9 probe lines, the 10th, nut, the 11st, comprehensive extension line, the 12nd, bolt, the 13rd, outer wall isolation valve, the 14th, detector, the 15th, ground wire, the 16th, ground stud, the 17th, conduction pipe over the ground, the 18th, transition insulation tube, the 19th, valve pit, the 20th, ring flange, the 21st, flange seal intermediate plate.Tap water is by 17 inputs of conduction pipe over the ground on figure the right, the transition insulation tube 18 of flowing through, outer wall isolation valve 13, arrive tested pipeline 6 then, pick out a ground wire 15 in the detector 14, it is connected with ground stud 16, also export a comprehensive line 11 in the detector 14, it enters into tested pipeline 6 through the flange seal intermediate plate 21 on outer wall isolation valve 13 left sides, 10,12, with 20 are common pipe web members, the ring flange that is enclosed within on the insulation tube wall 8 connects firmly by common pipe web member and outer wall isolation valve, comprising many lines in the comprehensive line, for the sake of clarity, we launch in tested pipeline, they are tapss 3, power lead 4, detection line 5, these lines all are the insulated conductors of outside seal, they and flange seal intermediate plate are formed termination recited above, each probe in the pipe is attempted by on these lines, probe is outside also to be sealed, Guan Zhongshui can not invade inside, but from probe circuit, draw one can with the water receiving contact 7 of water conducting, probe can have a plurality of, there is probe line 9 that they are electrically connected between each probe, distance between first probe behind the conduction pipe and second probe is generally less than the length of transition isolated pipe over the ground, all keep bigger resistance value between the water receiving contact of all probes and the earth when water-tight like this, when occurring leaking, the resistance to earth value of water receiving contact that has a probe at least is less than initial value, this zone of living in of popping one's head in promptly is the leakage point region, and can estimate the approximate location that leak source in this zone according to the size of resistance to earth value.
Fig. 2 is the testing circuit schematic diagram that leaks of each zone probe electrical communication in pipe in the insulation water pipe.
The fundamental purpose of using this circuit is take turns to detect water receiving contact in each probe and the resistance value between the earth.Can select all kinds of circuit according to actual needs in actual use, only introduce a kind of tour formula electronic detection circuit here.The inner detector circuit that divides in the presentation graphs 1 of dotted line among the figure, use a among the figure in the frame of broken lines, b, c, d, five English lower case of e represent that detector outwards draws five lines, wherein a is with 3 tapss of representing among Fig. 1, b, c is with 4 power leads of representing among Fig. 1, d is with 5 detection lines of representing among Fig. 1, e is with 15 ground wires of representing among Fig. 1, IC1 among Fig. 2 is a ring counter integrated package (as 4017), O1 is an optocoupler, they and diode D6, D3, D4, in D5 and resistance R 1 composition diagram 1 with the internal wiring of 2 probes of representing, t1 among Fig. 2 is the water receiving contact that the probe internal wiring is outwards drawn, this contact represents with 7 that in Fig. 1 SR1 dotted line resistance represents that t1 is by managing interior water or leaking to resistance greatly; The internal wiring of popping one's head among Fig. 2 is listed three groups altogether, except that above-mentioned one group, forms second group by IC2, O2 and D10, D7, D8, D9 and R2; Form the 3rd group by IC3, O3 and D14, D11, D12, D13 and R3; T2, t3 are respectively the water receiving contacts of two groups of circuit, and SR2, SR3 are that t2, t3 are by managing interior water or leaking to resistance greatly.X in the dotted line is for making an inspection tour the pulse cycle digital display instrument, and F is a pulse producer, and K is the on-off circuit that can the gating pulse electric current passes through, B is a warning circuit, and Z is the alarm lamp in the warning circuit, as the J that feeds back the signal registering instrument with door Y and conduct that has that feeds back the signal processing, S is the counting steady arm, L is an error correction interception switch, and q is the contrast electric bridge, and P is a relay, P1 is the contact that is subjected to relay control, BP is half frequency device, and CL is a power pack, and E1, E2 are two groups of power supplys.M pin on 4017 integrated packages is the zero setting pin, the N pin is the pulse signal input pin, 2, the 3rd, the counting output pin, and the 1st pin is the initial pin of each integrated package, when+when 5V powers to integrated package, each integrated package first pin all has voltage output (adopting 4017 o'clock actual the 3rd pin is initial pin, and 1,2,3 pin are here only represented the sequencing exported), and therefore all the other integrated packages all are in the value zero condition owing to the M pin has positive electricity except that IC1, and at this moment the equal no current of the diode in the optocoupler passes through.M pin owing to IC1 when pulse producer F begins to export first pulse is not in the zero setting state all the time, so pulse signal has only elder generation to trigger IC1 and makes its output pin fade to crus secunda by first pin, so all on the output optocoupler of count integration block, having only in the diode of optocoupler O1 has electric current to pass through, when second pulse arrives, the 3rd output pin of IC1 is malleation, malleation makes input pin N get electric and pulse signal annihilation after inciting somebody to action through D3, when the 3rd pulse arrives, because IC2 at this moment zero setting pin M has lost positive electricity so be not in the zero setting state, so when the 3rd pulse is input to input pin N, the IC2 output pin becomes 2 pin by 1 pin, therefore at this moment all count integration blocks have only in the diode of O2 optocoupler and have electric current to pass through, when the 4th pulse arrives, make the 2nd output pin of IC2 become the 3rd output pin again, positive electricity makes its input end for just making its annihilation through D7, when the 5th pulse arrives, because IC3 at this moment zero setting pin M also loses positive electricity and is not in the zero setting state, so the 5th pulse input is also arranged on its input pin N, and make the IC3 output pin become 2 pin by 1 pin, therefore at this moment all count integration blocks have only in the diode of optocoupler O3 and have electric current to flow through, by that analogy, two pulses of every output in the controller, having only in whole probes of Fig. 2 in the diode of an optocoupler has electric current to pass through, that is to say and have only a phototriode conducting in whole optocouplers, that is be in whole water receivings contact, have only a water receiving contact to get electric and return logical by the earth and instrument.Power pack CL just has electric current to flow through, because registering instrument is subjected to the time main pulse signal control of sending the device frequently from half, so send a pulse to registering instrument when partly device is every frequently, registering instrument just writes down once, and all have just been buried underground when intact at water pipe, owing to do not leak, what sent by certain regional receiver is a resistance value bigger when not leaking so registering instrument is noted, registering instrument is just this resistance value record maintenance and as benchmark, when registering instrument is received from the pulse signal that sends in this zone in regular turn once more, registering instrument will send former that bigger resistance signal value of noting to the input end of contrast electric bridge q, meanwhile contrast electric bridge q by the identical instant resistance signal value of sending by this zone receiver of pulse sequence number of another input end input, contrast electric bridge q will compare two resistance value signals, if it is more that reference resistor value is higher than instant resistance value, represent that then tested zone leaks, so among the contrast electric bridge q very big output current is arranged promptly, this electric current is during greater than alarm setting value, contrast electric bridge q promptly has signal output, on the input pin of electric signal arrival and door Y, in addition by D2 with the pulse signal electric current of pulse producer be input to half frequently behind the device from half frequently the device to on-off circuit K output half pulse frequently, (half frequently device BP have the function that frequency is reduced half just have the output diode of a receiver to be in channel status because send two frequencies from F).Simultaneously by error correction switch L, will half pulse frequently be input to another input end with door Y.When not leaking, go out not output of pin like this with door Y, the pulse of D2 output is by on-off circuit the time, to trigger tour pulse cycle digital display instrument counts, when leaking, output is arranged with door Y, this output current will make the on-off circuit K of gating pulse close, so make an inspection tour the pulse cycle digital display instrument count value is rested on this position, we just can find the position that leaks of pipeline according to the numerical value that stops.Simultaneously also send alarm signal, light alarm lamp Z to alarm B with door.S among the figure is the counting steady arm, it is according to the definite numeral that how much decides this number of probe quantity, as triggering the internal circuit of 1000 groups of probes altogether, then when occurring 1000 on the counter, among the steady arm S just to relay P output voltage, make relay P adhesive, the relay contact P1 of control power supply promptly disconnects, just outage of all probes like this, meanwhile make counter zero setting by S to making an inspection tour zero setting signal of pulse cycle digital display instrument output, then the automatic restoring circuit among the S makes relay P dead electricity again, and circuit is connected again, said mechanism is started working again, pulse is maked an inspection tour played the effect of going round and beginning again.D4, D5, D8, D9, D12, D13 are isolating diode among the figure, and R1, R2, R3 stablize and the stake resistance of usefulness the zero setting end.L among the figure is the error correction configuration switch, when certain detection head is detected when being wrong signal or the leak source repaired, be on the 100th pulse position as this detection head, then by operating personnel 100 these numbers are input in the error correction switch, the error correction switch sends an inhibition signal to AND circuit when the 100th pulse occurs, and makes the not output with door Y, on-off circuit K is in channel status, counter continues counting, can not pause, and continues down to detect.
Fig. 3 is the electric detection architecture synoptic diagram that leaks that does not communicate in each zone probe is managed in the insulation water pipe.7 is water receiving contacts of probe among the figure, the 22nd, the termination insulation course, the 23rd, wiring, the 24th, a kind of probe simple in structure (its shell is an insulator, and inside has a lead to link to each other with the water receiving contact), the 16th, ground stud, the 6th, tested pipeline, the 8th, insulation tube wall, the 1st, ground, the 25th, insulation tube and the joint flange between conduction pipe over the ground, the 17th, conduction pipe over the ground.Probe 2 simple in structure passes insulation tube wall 8 and is inserted in the tested pipeline 6, and a water receiving contact 7 is arranged on the probe of no internal wiring, and it and wiring 23 are electrically connected, and wiring has termination insulation course 22 outward.This structure can be divided into two kinds of modes in detection, a kind of is when confirming not leak, and contacts wiring 23 and ground stud 16 respectively with two table rods of ammeter, records original resistance; In the time of in use need detecting, such as the survey resistance less than original resistance, then calibrating is the generation of leaking of this zone, and goes out to leak in this regional approximate location according to the resistance magnitude estimation.Another kind is only to see the water receiving contact as among Fig. 1 water receiving contact, and will pop one's head in and 24 change the form of making among Fig. 1 probe 2, also be about to be arranged among Fig. 1 taps in the pipe, power lead, detection line, probe line etc. and place outside the isolated pipe, and can adopt the testing circuit that leaks among Fig. 2 its detection of leaking.
Fig. 4 is the flow-type probe detection architecture synoptic diagram that leaks in the insulation water pipe.26 is ammeters as detector among the figure, the 27th, and transmission pressure, the 28th, translucent cover, the 29th, have the external insulation loop of distance scale, the 30th and the axle that is electrically connected of wiper mechanism, the 31st, wiper mechanism, the the 32nd and the affixed rocking arm of axle, the 33rd, insulation tube three-way interface, the 34th, leak, the 7th, the water receiving contact, the 35th, the probe that can float, the 8th, insulation tube wall, the 36th, external insulation lead, the 6th, water channel, the 16th, ground stud.The centre of cloche 28 is inserted with axle 30 among Fig. 4, the inner end of axle is connected with rocking arm 32 outside cloche, the outer end can make external insulation loop 29 and transmission pressure 27 still keep being electrically connected when axle rotates by wiper mechanism 31, cloche can revolve the jail on insulation tube three-way connection 33, transmission pressure 27 connects a binding post of detector ammeter 26, another binding post ground stud 16 of ammeter 26, the External Cordon Line of external insulation loop 29 is pulled out and is formed external insulation lead 36, lead 36 connects water receiving contact 7, water receiving contact 7 anchors on the probe 35 that can float, it can drift about in the water in water channel 6, and arrow is represented water (flow) direction among the figure.During detection with the hand arm 32 that shakes, make insulated conductor circle 29 unwrapping wire, current drift about probe from left to right, leak as nothing, then the measuring current in the ammeter through transmission pressure arrives cloche by wiper mechanism in the external insulation loop and with 36 leads of representing and water receiving contact 7, logical the earth will could be returned by relatively long distance in the pipe in the water receiving contact, so water resistance is bigger, at this moment occurs lower current value on the ammeter; When producing the scupper of representing as Figure 34 in the insulation tube, probe floats point so far, the water receiving contact will be connected from scupper and the earth, because this segment distance is nearer relatively, therefore water resistance is less, at this moment will occur a bigger current value on the ammeter, and have distance scale on the external insulation lead, and take this scale and know that just leakage point leaves the distance of insulation tube threeway 33.
For the insulating tube water channel that the fork road is arranged, for the direction of knowing that probe drifts about, can also on probe, the direction indication sensor be set, the direction transformation signal is fed back to tester.

Claims (1)

1. insulating tube water channel leak detecting method, it comprises a detector with ground loop, detector connects the probe that has the water receiving contact by termination, probe places insulating tube water channel, and it is characterized in that: the signal that leaks of isolated pipe is to realize by the resistance to earth variable of popping one's head in the detector tube.
CNA2007101276729A 2007-06-24 2007-06-24 Insulating tube water channel leak detecting method Pending CN101246077A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CNA2007101276729A CN101246077A (en) 2007-06-24 2007-06-24 Insulating tube water channel leak detecting method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CNA2007101276729A CN101246077A (en) 2007-06-24 2007-06-24 Insulating tube water channel leak detecting method

Publications (1)

Publication Number Publication Date
CN101246077A true CN101246077A (en) 2008-08-20

Family

ID=39946655

Family Applications (1)

Application Number Title Priority Date Filing Date
CNA2007101276729A Pending CN101246077A (en) 2007-06-24 2007-06-24 Insulating tube water channel leak detecting method

Country Status (1)

Country Link
CN (1) CN101246077A (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102998070A (en) * 2011-09-09 2013-03-27 珠海格力电器股份有限公司 Testing method for sealed electric box
CN105067194A (en) * 2015-05-28 2015-11-18 中航光电科技股份有限公司 Sealing detection device and method for electric rotating connector
CN105424293A (en) * 2015-12-02 2016-03-23 深圳凌水环保科技股份有限公司 Water supply-drainage pipe leak detection system and detection method
CN105465614A (en) * 2016-02-16 2016-04-06 深圳凌水环保科技股份有限公司 Water supply and drainage pipe leakage detecting system and method
CN105829854A (en) * 2013-12-20 2016-08-03 阿海珐有限公司 Leak-monitoring system for space-enclosing objects and coupling regions lying therebetween, as well as an associated method
CN106383011A (en) * 2016-08-19 2017-02-08 上海科勒电子科技有限公司 Water leakage sensor
CN109296943A (en) * 2018-12-13 2019-02-01 上海嘉实(集团)有限公司 A method of being applied to retrospect leakage point in building automatic management system
CN110044550A (en) * 2019-05-22 2019-07-23 西南石油大学 A kind of ocean non-adherent flexible duct external sheath layer damage detection device and method

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102998070A (en) * 2011-09-09 2013-03-27 珠海格力电器股份有限公司 Testing method for sealed electric box
CN105829854A (en) * 2013-12-20 2016-08-03 阿海珐有限公司 Leak-monitoring system for space-enclosing objects and coupling regions lying therebetween, as well as an associated method
CN105829854B (en) * 2013-12-20 2019-08-16 阿海珐有限公司 Space-closed object and the leakage monitoring system and corresponding method of bonding land therebetween
CN105067194A (en) * 2015-05-28 2015-11-18 中航光电科技股份有限公司 Sealing detection device and method for electric rotating connector
CN105424293A (en) * 2015-12-02 2016-03-23 深圳凌水环保科技股份有限公司 Water supply-drainage pipe leak detection system and detection method
CN105465614A (en) * 2016-02-16 2016-04-06 深圳凌水环保科技股份有限公司 Water supply and drainage pipe leakage detecting system and method
CN105465614B (en) * 2016-02-16 2019-04-19 深圳凌水环保科技股份有限公司 A kind of supplying drainage leak detection system and detection method
CN106383011A (en) * 2016-08-19 2017-02-08 上海科勒电子科技有限公司 Water leakage sensor
CN106383011B (en) * 2016-08-19 2019-01-22 上海科勒电子科技有限公司 Leakage sensor
CN109296943A (en) * 2018-12-13 2019-02-01 上海嘉实(集团)有限公司 A method of being applied to retrospect leakage point in building automatic management system
CN110044550A (en) * 2019-05-22 2019-07-23 西南石油大学 A kind of ocean non-adherent flexible duct external sheath layer damage detection device and method

Similar Documents

Publication Publication Date Title
CN101246077A (en) Insulating tube water channel leak detecting method
CN202994907U (en) Insulation impedance detection system of photovoltaic inverter
CN107765149A (en) The insulation detection device of integrated multifunction
CN201062997Y (en) Apparatus for detecting leakage of insulating tube watercourse
CN107794882A (en) A kind of geomembrane and its leakage detection method for being easy to large area leak detection
CN107179467A (en) GIL Fault Locating Methods and fault location system based on earth current
CN104947118A (en) Flexible anode breakpoint detecting method
CN103543321B (en) A kind of polarization for crosslinked polyethylene midium voltage cable-depolarization current pick-up unit
CN205560296U (en) Water supply and drainage pipe leak testing system
CN105606960B (en) Marine settings distribution line ground fault detection system
CN108709917A (en) Tubular type TDR soil moisture sensors
CN103528767B (en) For the leaking area pick-up unit of large area region
CN100425904C (en) Electronic touring water pipeline leakage inspection
CN201852886U (en) Multifunctional earth resistance tester
CN200958687Y (en) Corresponding pulse pipeline leakage alarming system
CN213579963U (en) Lining layer water measuring system for preventing cold region tunnel from freezing damage
CN205642544U (en) Atmospheric pressure conduction device and municipal drainage pipe network water position monitoring node
CN201444065U (en) Liquid level temperature sensor
CN104280151B (en) Temperature testing system for high-pressure high-humidity underground rock-soil in long distance mode and connecting method thereof
CN106706720A (en) Resistance controlled portable multi-depth moisture content field measurement device
CN106814294A (en) Based on bilateral bridge direct-current charging post insulation detecting circuit and detection method
CN208043066U (en) A kind of hydrology practicality flow measurement signal receiver
CN216274378U (en) Cathodic protection monitoring and detecting test pile
CN104372349A (en) Novel pipeline detection digital probe
CN108415104A (en) Tapered solar energy storing up electricity rain recorder

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C12 Rejection of a patent application after its publication
RJ01 Rejection of invention patent application after publication

Open date: 20080820