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JP-2026075025-A - Measuring device

JP2026075025AJP 2026075025 AJP2026075025 AJP 2026075025AJP-2026075025-A

Abstract

[Challenge] To enable accurate correction of the internal time. [Solution] The data processing device 1 includes a temperature determination unit 181 that determines the seabed temperature at the location on the seabed where a measuring device is installed that creates measurement data of seismic waves associated with an internal time in which seismic waves were detected in response to vibration waves being emitted from the source of the earthquake; a temperature reduction unit 182 that lowers the temperature of an oscillator 41 built into a measuring device located outside of seawater to the seabed temperature; a rate measurement unit 183 that measures the aging rate, which is the rate of change in the frequency of the oscillator 41 over time, when the temperature of the oscillator 41 built into the measuring device located outside of seawater has reached the determined seabed temperature; and a correction unit 188 that corrects the internal time associated with the measurement data based on the aging rate after the measuring device installed on the seabed has created the measurement data. [Selection Diagram] Figure 8

Inventors

  • 清水 賢
  • 田中 耕太郎
  • 祖父江 克也

Assignees

  • サイスガジェット株式会社

Dates

Publication Date
20260507
Application Date
20250124

Claims (9)

  1. An oscillator used for timing the internal time, A temperature change device for changing the temperature of the oscillator, A processor that controls the temperature change device so that the temperature change device changes the temperature of the oscillator, A seismic wave measurement unit creates measurement data of the seismic waves associated with an internal time when seismic waves are detected in response to the emission of seismic waves from the epicenter, A measuring device having the following features.
  2. The temperature-changing device is made of a material that absorbs heat on one side and releases the absorbed heat on the other side. The measuring device according to claim 1.
  3. The aforementioned temperature-changing device is made of a material that can swap its heat-absorbing surface and heat-dissipating surface by changing the direction of the current flowing through it. The measuring device according to claim 2.
  4. The temperature change device is installed so as to be in contact with the outer surface of the measuring device. The processor controls the direction of the current flowing through the temperature change device such that the surface of the temperature change device in contact with the outer surface of the measuring device becomes a heat-absorbing surface. The measuring device according to claim 3.
  5. The device further comprises a first generating unit that generates a voltage to be applied to the temperature change device. The measuring device according to claim 1.
  6. It further has an operating section for the user to perform operations, The first generating unit generates a voltage in response to the user performing an operation on the operating unit to apply a voltage to the temperature change device. The measuring device according to claim 5.
  7. The measuring device according to claim 5, wherein the first generating unit generates a voltage in response to the external power supply that generates the voltage applied to the temperature change device and the wiring connecting the temperature change device to the temperature change device being removed from the temperature change device.
  8. The first generating unit stops applying the voltage after a predetermined time has elapsed from the start of voltage application until the oscillator of the measuring device installed on the seabed is cooled to seabed temperature by seawater after the measuring device has been submerged in the sea. The measuring device according to claim 5.
  9. The system further includes a second generating unit that generates a voltage to be applied to the oscillator. The measuring device according to claim 5.

Description

This invention relates to a measuring device for measuring seismic waves. Since the oscillation frequency of a crystal oscillator changes over time, techniques for adjusting the oscillation frequency are known (see, for example, Patent Document 1). Japanese Patent Publication No. 2010-245978 This is a diagram illustrating the seismic wave measurement system S.This figure shows an example of the temperature change in a conventional oscillator.This diagram shows the relationship between the external device 1, the measuring device 4, and the temperature change device 5 according to the first embodiment.This is a flowchart showing the flow of the measurement method according to the first embodiment.This is a schematic diagram showing the temperature change of the oscillator during the measurement method according to the first embodiment.This diagram illustrates the procedure for activating multiple measuring devices 4.This figure shows an example of a management table that indicates the status of each measuring device 4.This diagram shows the configuration of the data processing device 1 according to the first embodiment.This graph shows the amount of time drift over time.This figure shows an example of a flowchart illustrating the internal time correction process according to this embodiment.This figure shows the configuration of the measuring device 4 according to the first embodiment.This is a flowchart showing the flow of the measurement method according to the second embodiment.This is a schematic diagram showing the temperature change of the oscillator during the measurement method according to the second embodiment.This figure shows the configuration of the measuring device 4 according to the second embodiment. <First Embodiment> [Overview of Measurement System S] Figure 1 shows an overview of the measurement system S. The measurement system S is an ocean geophysical exploration system for analyzing the subseafloor geological structure. In the measurement system S, vibration waves are generated from a source 2 such as an air gun or sparker, and a data processing device 1 uses the results of vibration wave measurements by numerous measuring devices 4 installed on the seabed to analyze the subseafloor geological structure. The measurement system S comprises a data processing device 1, a seismic source 2, an optical communication device 3, and a plurality of measurement devices 4. The data processing device 1, seismic source 2, and optical communication device 3 are mounted on a vessel 100 capable of navigating the ocean. The plurality of measurement devices 4 are installed on the seabed at intervals of a predetermined distance or greater. The data processing device 1 is, for example, a computer. It acquires measurement data indicating the seabed vibration state observed by multiple measuring devices 4 at the timing of seismic wave emission, and analyzes the acquired measurement data. Specifically, the data processing device 1 analyzes the seismic wave measurement data detected by the measuring devices 4 in response to seismic waves emitted from the epicenter 2 towards the seabed from a ship navigating the sea during the measurement period. As shown in Figure 1(a), the data processing device 1 controls the multiple measuring devices 4 by transmitting and receiving acoustic signals, and also receives the measurement data generated by the multiple measuring devices 4. Furthermore, the data processing device 1 acquires information indicating absolute time from, for example, a PTP network or GPS (Global Positioning System). The seismic source 2 generates vibration waves during the measurement period. The seismic source 2 generates vibration waves based, for example, on the control of the data processing device 1, but it may also generate vibration waves based on the control of a different control device (for example, a computer installed on a ship different from ship 100). The optical communication device 3 acquires measurement data from at least one measuring device 4 by communicating optically with it based on the control of the data processing device 1. The optical communication device 3 emits a first optical signal to the measuring device 4 underwater, and receives a second optical signal transmitted by the measuring device 4 that received the first optical signal. The optical communication device 3 is connected to the data processing device 1 by cable C, and, based on the control of the data processing device 1, dives to a position where it can communicate optically with the measuring device 4, and then communicates optically with the measuring device 4. The optical communication device 3 moves sequentially to the vicinity of multiple measuring devices 4 and sequentially acquires measurement data from multiple measuring devices 4. Note that the measurement system S may have multiple optical communication devices 3, and multiple optical communication devices 3 may acquire measurement data from multiple meas