JPS56166481A - Deciding method of earthquake - Google Patents

Deciding method of earthquake

Info

Publication number
JPS56166481A
JPS56166481A JP7002080A JP7002080A JPS56166481A JP S56166481 A JPS56166481 A JP S56166481A JP 7002080 A JP7002080 A JP 7002080A JP 7002080 A JP7002080 A JP 7002080A JP S56166481 A JPS56166481 A JP S56166481A
Authority
JP
Japan
Prior art keywords
circuit
supplied
earthquake
variable gain
movement
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.)
Granted
Application number
JP7002080A
Other languages
Japanese (ja)
Other versions
JPS6026472B2 (en
Inventor
Hajime Kakehi
Keisuke Hoshino
Hiroshi Takizawa
Yoshiaki Kono
Atsuaki Hachitani
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.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP55070020A priority Critical patent/JPS6026472B2/en
Publication of JPS56166481A publication Critical patent/JPS56166481A/en
Publication of JPS6026472B2 publication Critical patent/JPS6026472B2/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
    • G01V1/28—Processing seismic data, e.g. for interpretation or for event detection
    • G01V1/30—Analysis

Landscapes

  • Engineering & Computer Science (AREA)
  • Remote Sensing (AREA)
  • Physics & Mathematics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Acoustics & Sound (AREA)
  • Environmental & Geological Engineering (AREA)
  • Geology (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Geophysics (AREA)
  • Geophysics And Detection Of Objects (AREA)

Abstract

PURPOSE:To enable a proper trigger decision to be performed even when the ground noise is nonstationary, by connecting a variable gain amplifying circuit to the stage previous to a filter circuit. CONSTITUTION:The digital input signal sent from an earthquake telemeter is supplied to a filter circuit 3 from an input terminal 1 through a variable gain amplifying circuit 2 in order to pass only the component to be observed, which is supplied to an absolute value circuit 4. The signal therefrom is supplied to a short-time movement averaging circuit 6, where a movement average value by a short-time sampling is obtained. Said signal is supplied also to a long-time movement averaging circuit 5 through a switching circuit 51, where a movement average value by a long-time sampling is obtained. The latter, which is obtained only when there is no earthquake through the circuit 51 which is closed then, is an average ground noise, which is multiplied by alpha in a multiplier circuit 71 and compared with the former to decide an earthquake. In addition, the latter is compared with a set value 81 in order to control the gain of the variable gain amplifying circuit 2 so that the average ground noise is slightly higher than the noise level resulting from the arithmetic error.
JP55070020A 1980-05-28 1980-05-28 Earthquake judgment method Expired JPS6026472B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP55070020A JPS6026472B2 (en) 1980-05-28 1980-05-28 Earthquake judgment method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP55070020A JPS6026472B2 (en) 1980-05-28 1980-05-28 Earthquake judgment method

Publications (2)

Publication Number Publication Date
JPS56166481A true JPS56166481A (en) 1981-12-21
JPS6026472B2 JPS6026472B2 (en) 1985-06-24

Family

ID=13419499

Family Applications (1)

Application Number Title Priority Date Filing Date
JP55070020A Expired JPS6026472B2 (en) 1980-05-28 1980-05-28 Earthquake judgment method

Country Status (1)

Country Link
JP (1) JPS6026472B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59195178A (en) * 1983-04-21 1984-11-06 Fujitsu Ltd Earthquake deciding method
EP1540616A4 (en) * 2002-08-30 2006-06-07 Seismic Warning Systems Inc Sensor apparatus and method for detecting earthquake generated p- waves and generating a responsive control signal

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59195178A (en) * 1983-04-21 1984-11-06 Fujitsu Ltd Earthquake deciding method
JPH057674B2 (en) * 1983-04-21 1993-01-29 Fujitsu Ltd
EP1540616A4 (en) * 2002-08-30 2006-06-07 Seismic Warning Systems Inc Sensor apparatus and method for detecting earthquake generated p- waves and generating a responsive control signal

Also Published As

Publication number Publication date
JPS6026472B2 (en) 1985-06-24

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