Earthquake Detection System and Method Using Regional and Auxiliary Seismic Networks

Abstract

The present invention relates to an earthquake detection system and method utilizing a wide-area earthquake station and an auxiliary earthquake station simultaneously, comprising: a first measurement unit that primarily measures a first earthquake signal through a sensor at a plurality of auxiliary earthquake stations installed in an urban area or a boundary area of ​​a wide-area earthquake station; a second measurement unit that secondarily measures a second earthquake signal through a sensor at a wide-area earthquake station near the auxiliary earthquake station; a signal filtering unit that preprocesses the first earthquake signal; an earthquake detection unit that detects an earthquake using a candidate P-wave among the seismic waves of the first earthquake signal preprocessed by the signal filtering unit; an earthquake verification unit that verifies the earthquake detection by confirming whether the first earthquake signal of the detected earthquake is detected in the second earthquake signal measured at the wide-area earthquake station near the auxiliary earthquake station when the magnitude of the detected earthquake is greater than or equal to a set threshold; and an alarm notification unit that transmits an alarm to a necessary agency when the verified magnitude of the earthquake is greater than or equal to a set threshold.

Description

Technology Field

[0001] The present invention relates to an earthquake detection system and method, and more specifically, to an earthquake detection system and method that simultaneously utilizes a wide-area earthquake station and an auxiliary earthquake station to detect an earthquake by using P-waves from earthquake signals of an auxiliary earthquake station installed in an urban area or at the boundary of a wide-area earthquake station on the Korean Peninsula, and secondarily verifies the detected earthquake by checking whether the corresponding earthquake signal is detected at a nearby wide-area earthquake station, and transmits an alarm notification to the necessary agency if the magnitude of the detected earthquake is greater than or equal to a threshold. Background Technology

[0002] Earthquakes are natural disasters caused by seismic waves passing through the rock layers of the Earth's crust. According to observational data from the U.S. Geological Survey (USGS), earthquakes of magnitude 8 or higher occur once a year worldwide, earthquakes of magnitude 7 or higher occur about 16 times a year, and earthquakes of magnitude 6 or higher occur about 150 times a year. Although there may be differences depending on the location of the earthquake, environmental factors, and the extent of seismic-resistant facilities, an earthquake of magnitude 6 or higher can be considered a strong earthquake that causes social damage.

[0003] Strong earthquakes occur globally at a rate of once every two to three days, and they frequently occur in the region known as the "Ring of Fire," which includes the Pacific coastal areas such as Japan, Taiwan, Southeast Asia, the western part of the Americas, and the South American coast, which are famous for their high frequency of earthquakes. The Korean Peninsula has been regarded as an "earthquake-safe zone" with a lower frequency of earthquakes compared to the aforementioned regions.

[0004] However, it has been found that the frequency of earthquakes in the Korean Peninsula and surrounding waters has increased recently. From January 2023 to July 2023, a total of 59 earthquakes of magnitude 2.0 or higher occurred, of which 10 were of magnitude 3 or higher, meaning that most people around the epicenter could feel the tremors. This figure is significantly higher compared to the annual average of 10.5 earthquakes of magnitude 3 or higher from 1999 to 2021. Among the earthquakes that occurred on the Korean Peninsula, the earthquake in Gyeongju in 2016 and the earthquake in Pohang in 2017 were of magnitude 5 or higher, indicating that strong earthquakes of magnitude 5 or higher are also occurring on the Korean Peninsula.

[0005] Therefore, the Korean Peninsula is no longer an 'earthquake-safe zone,' and the development of technology for early earthquake detection and warning systems is required to reduce damage caused by earthquakes.

[0006] The matters described above as background technology are intended only to enhance understanding of the background of the present invention and should not be construed as an acknowledgment that they constitute prior art already known to those skilled in the art. Prior art literature

[0007] Korean Patent Publication No. 10-1391226 (April 25, 2014) Korean Patent Publication No. 10-1715898 (March 7, 2017) The problem to be solved

[0008] Accordingly, the present invention is proposed to resolve the aforementioned conventional problems and aims to provide a system and method capable of enhancing the reliability of earthquakes detected by auxiliary earthquake observation stations by constructing multiple auxiliary earthquake observation stations in urban areas or boundary areas of the Korean Peninsula's wide-area earthquake observation stations and performing secondary verification using data acquired from the wide-area earthquake observation stations capable of more precise earthquake detection.

[0009] Furthermore, the present invention aims to provide a system and method that can reduce the time and cost required for early earthquake warnings by acquiring data and detecting earthquakes using auxiliary earthquake observation stations installed in multiple locations, such as urban areas or boundary areas of the Korean Peninsula's wide-area earthquake observation stations, in order to resolve the aforementioned conventional problems. means of solving the problem

[0010] The earthquake detection system (1) utilizing a wide-area earthquake station and an auxiliary earthquake station simultaneously according to the present invention for achieving the above-mentioned purpose comprises: a first measurement unit that primarily measures a first earthquake signal through a sensor at a plurality of auxiliary earthquake stations installed in an urban area or a boundary area of ​​a wide-area earthquake station; a second measurement unit that secondarily measures a second earthquake signal through a sensor at a wide-area earthquake station near the auxiliary earthquake station; a signal filtering unit that preprocesses the first earthquake signal; an earthquake detection unit that detects an earthquake using a candidate P-wave among the earthquake waves of the first earthquake signal preprocessed by the signal filtering unit; an earthquake verification unit that verifies the earthquake detection by confirming whether the first earthquake signal of the detected earthquake is detected in the second earthquake signal measured at the wide-area earthquake station near the auxiliary earthquake station when the magnitude of the detected earthquake is greater than or equal to a set threshold; and an alarm notification unit that transmits an alarm to a necessary agency when the magnitude of the verified earthquake is greater than or equal to a set threshold.

[0011] Here, the number of auxiliary seismic observation stations is characterized as being greater than the number of wide-area seismic observation stations.

[0012] In addition, the seismic signal is characterized by being at least one of the type, amplitude, velocity, and acceleration information of the seismic wave, and the type of the seismic wave is characterized as being a P-wave, and the sensor installed at the auxiliary seismic station is characterized as being at least one of an auxiliary seismic sensor including a MEMS-based micro accelerometer sensor or a geophone, and the sensor installed at the wide-area seismic station is characterized as being a seismometer.

[0013] In embodiments of the present invention, the earthquake detection unit comprises: a detection module that detects candidate P-waves among the seismic waves of the first earthquake signal preprocessed in the signal filtering unit; a calculation module that, when the candidate P-wave is detected at one of the plurality of auxiliary earthquake stations in the detection module, calculates the number of candidate P-waves measured at the plurality of auxiliary earthquake stations including the auxiliary earthquake station where the candidate P-wave was detected, and the maximum amplitude values ​​of the auxiliary earthquake stations where the candidate P-waves were detected, for 2 seconds from the time of detection of the candidate P-wave; a location calculation module that, when the number of candidate P-waves calculated by the calculation module is greater than or equal to a reference number, estimates the location of occurrence of the first earthquake signal where the candidate P-wave was detected and assumes the candidate P-waves as the P-waves of the first earthquake signal; and a magnitude calculation module that calculates the magnitude of the first earthquake signal where the P-wave was detected when the location of occurrence of the first earthquake signal is estimated by the location calculation module.

[0014] In embodiments of the present invention, the earthquake verification unit is characterized by determining whether, if the magnitude calculated by the magnitude calculation module is 3 or greater, a P-wave corresponding to the P-wave of the first earthquake signal, whose occurrence location is estimated by the location calculation module, is detected in the second earthquake signal measured at the wide-area earthquake observation station near the auxiliary earthquake observation station selected according to a preset priority.

[0015] In embodiments of the present invention, the alarm notification unit is characterized by determining that an earthquake has occurred and transmitting an earthquake alarm notification to the necessary agency when a P-wave corresponding to the P-wave of the first earthquake signal, whose occurrence location is estimated in the second earthquake signal, is detected by the earthquake verification unit.

[0016] More specifically, the above-mentioned prioritization is characterized in that the wide-area seismic station located within a radius of 50 km or less from the auxiliary seismic station where the first seismic signal including the candidate P-wave detected by the detection module was first measured is the first priority, the wide-area seismic station located within a radius of more than 50 km and less than or equal to 100 km from the auxiliary seismic station where the first seismic signal including the P-wave detected by the detection module was first measured is the second priority, and the wide-area seismic station located within a radius of more than 100 km from the auxiliary seismic station where the first seismic signal including the P-wave detected by the detection module was first measured is the third priority.

[0017] Here, the earthquake verification unit is characterized by determining whether a P-wave corresponding to the P-wave of the first earthquake signal, whose occurrence location is estimated, is detected in the second earthquake signal measured at the first-priority wide-area earthquake observation station.

[0018] In embodiments of the present invention, the location calculation module is characterized by estimating the location of occurrence of the first earthquake signal based on the quality grade of the wide-area earthquake station and the auxiliary earthquake station, and the quality grade is characterized by being determined according to the amplitude of the measured background noise by frequency by measuring the real-time background noise of the wide-area earthquake station and the auxiliary earthquake station for two hours.

[0019] More specifically, the quality grade is characterized in that the frequency-dependent amplitude of the measured background noise is Grade 1 if it is within the range of the high-noise model (HNM) and low-noise model (LHM) presented by McNamara and Buland (2004), and Grade 2 if it is outside the range.

[0020] In addition, the location calculation module calculates the time difference between the theoretical arrival time of the candidate P-wave and the actual arrival time of the candidate P-wave according to the candidate P-wave velocity at each of the auxiliary earthquake station where the first earthquake signal was measured, the auxiliary earthquake station having a quality grade of 1 within a radius of 50 km of the auxiliary earthquake station where the first earthquake signal was measured, and the wide-area earthquake station having a quality grade of 1 within a radius of 50 km of the auxiliary earthquake station where the first earthquake signal was measured, estimates the point that minimizes the total time difference as the location of occurrence of the first earthquake signal where the candidate P-wave was detected, and assumes the candidate P-wave as the P-wave of the first earthquake signal.

[0021] In embodiments of the present invention, the alarm notification unit further comprises an aftershock notification module that generates an intensity map and provides it to the meteorological agency if the magnitude calculated by the magnitude calculation module is 5 or greater.

[0022] Here, the aftershock notification module includes: an aftershock detection module that detects aftershocks occurring for 5 hours from the time the earthquake of magnitude 5 or higher occurred at an auxiliary earthquake station within a radius of 50 km from the epicenter of the earthquake of magnitude 5 or higher, if the magnitude calculated by the magnitude calculation module is 5 or higher; an intensity conversion module that converts acceleration into intensity whenever acceleration greater than a reference acceleration is measured at four or more of the auxiliary earthquake stations and wide-area earthquake stations within a radius of 50 km from the epicenter of the aftershock of magnitude 5 or higher detected by the aftershock detection module; and an aftershock information provision module that generates an intensity map using the converted intensity and provides the aftershock detection status and the intensity map to the necessary agency.

[0023] A method for detecting an earthquake by simultaneously utilizing a wide-area earthquake station and an auxiliary earthquake station according to the present invention comprises: a step of primarily measuring a first earthquake signal through a sensor at an auxiliary earthquake station installed in an urban area or a boundary area of ​​a wide-area earthquake station in a first measurement unit; a step of secondarily measuring a second earthquake signal through a sensor at a wide-area earthquake station near the auxiliary earthquake station in a second measurement unit; a step of preprocessing the first earthquake signal in a signal filtering unit; a step of detecting an earthquake using a candidate P-wave among the seismic waves of the first earthquake signal preprocessed in the step of preprocessing the first earthquake signal in an earthquake detection unit; and a step of verifying the earthquake detection in an earthquake verification unit by confirming whether the first earthquake signal of the detected earthquake is detected in the second earthquake signal measured at the wide-area earthquake station near the auxiliary earthquake station when the magnitude of the earthquake detected in the step of detecting an earthquake using the candidate P-wave is greater than or equal to a set threshold. The alarm notification unit is characterized by including a step of transmitting an alarm to a necessary agency when the magnitude of the earthquake verified in the verification step is greater than or equal to a set threshold. Effects of the invention

[0024] According to the earthquake detection system (1) and method utilizing both a wide-area earthquake observation station and an auxiliary earthquake observation station as described above, the following effects are achieved.

[0025] First, there is an effect of increasing the reliability of earthquakes detected by the auxiliary earthquake station through secondary verification using data acquired from the aforementioned wide-area earthquake station, which is capable of more precise earthquake detection.

[0026] Second, by acquiring data and detecting earthquakes using auxiliary seismic observation stations installed in large numbers in urban areas or at the boundary of wide-area seismic observation stations on the Korean Peninsula, it is possible to provide early earthquake warnings in urban areas prone to significant earthquake damage.

[0027] Third, by acquiring data and detecting earthquakes using auxiliary seismic observation stations installed in large numbers in urban areas or at the boundary of wide-area seismic observation stations on the Korean Peninsula, there is an effect of shortening the time required for early warning and reducing costs.

[0028] Fourth, by using both auxiliary seismic stations and wide-area seismic stations to estimate the location of the earthquake detected by the auxiliary seismic station, there is an effect of increasing the accuracy of estimating the location of the earthquake more than by using only one type of seismic station to estimate the location of the earthquake.

[0029] Fifth, by using the system according to the present invention, information on aftershocks of a large-magnitude earthquake is provided to relevant agencies, thereby enabling warning notifications regarding aftershocks and having the effect of reducing the scale of earthquake damage.

[0030] The effects obtainable from the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the present invention belongs from the description below. Brief explanation of the drawing

[0031] FIG. 1 is a configuration diagram of an earthquake detection system (1) according to one embodiment of the present invention. FIG. 2 is a configuration diagram of an earthquake detection unit (400) according to one embodiment of the present invention. FIG. 3 is a configuration diagram of an aftershock notification module (610) according to one embodiment of the present invention. FIG. 4a is an exemplary diagram showing the locations of the auxiliary seismic observation station and the wide-area seismic observation station of the present invention. FIG. 4b is another exemplary diagram showing the locations of the auxiliary seismic observation station and the wide-area seismic observation station of the present invention. FIG. 5 is a flowchart illustrating an earthquake detection method according to one embodiment of the present invention. Specific details for implementing the invention

[0032] With reference to the attached drawings, an earthquake detection system (1) and method utilizing a wide-area earthquake observation station and an auxiliary earthquake observation station simultaneously according to embodiments of the present invention will be described in detail. Since the present invention is subject to various modifications and may take various forms, specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to specific disclosed forms, and it should be understood that it includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the present invention. Similar reference numerals have been used for similar components in the description of each drawing. In the attached drawings, the dimensions of the structures are shown enlarged from the actual size to ensure clarity of the present invention, or reduced from the actual size to understand the schematic configuration.

[0033] Additionally, terms such as "first," "second," etc., may be used to describe various components, but said components should not be limited by said terms. These terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be named the second component, and similarly, the second component may be named the first component. Meanwhile, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application.

[0034] The present invention relates to an earthquake detection system and method, and more specifically, to an earthquake detection system that simultaneously utilizes a wide-area earthquake station and an auxiliary earthquake station to detect an earthquake by using P-waves from earthquake signals of an auxiliary earthquake station installed in an urban area or at the boundary of a wide-area earthquake station on the Korean Peninsula, and secondarily verifies the detected earthquake by confirming whether the corresponding earthquake signal is detected at a nearby wide-area earthquake station, and transmits an alarm notification to the necessary agency if the magnitude of the detected earthquake is greater than or equal to a threshold.

[0035] FIG. 1 is a configuration diagram of an earthquake detection system (1) according to one embodiment of the present invention.

[0036] As illustrated in FIG. 1, the earthquake detection system (1) utilizing a wide-area earthquake observation station and an auxiliary earthquake observation station simultaneously according to the present invention is characterized by including a first measurement unit (100), a second measurement unit (200), a signal filtering unit (300), an earthquake detection unit (400), an earthquake verification unit (500), and an alarm notification unit (600).

[0037] More specifically, the first measurement unit (100) is a component that primarily measures a first earthquake signal through a sensor at an auxiliary earthquake station installed in an urban area or at the boundary of a wide-area earthquake station, and the second measurement unit (200) is a component that secondarily measures a second earthquake signal through a sensor at the wide-area earthquake station near the auxiliary earthquake station, the signal filtering unit (300) is a component that preprocesses the first earthquake signal, and the earthquake detection unit (400) is a component that detects an earthquake using candidate P-waves among the seismic waves of the first earthquake signal preprocessed by the signal filtering unit (300), and the earthquake verification unit (500) is a component that verifies the earthquake detection by confirming whether the first earthquake signal of the detected earthquake is detected in the second earthquake signal measured at the wide-area earthquake station near the auxiliary earthquake station when the magnitude of the detected earthquake is greater than or equal to a set threshold, and finally, the alarm notification unit (600) is a component that, when the verified magnitude of the earthquake is greater than or equal to a set threshold, necessary It is a component that transmits alarm signals to the organization.

[0038] Here, the seismic signal is characterized by being at least one of the type, amplitude, velocity, and acceleration information of the seismic wave measured by the sensor, the time of occurrence of the seismic wave, and the time of detection of the seismic wave, and the type of the seismic wave is characterized by being at least one of a P-wave and an S-wave.

[0039] In addition, the sensor installed at the auxiliary seismic station is characterized as being at least one of an auxiliary seismic sensor including a MEMS-based micro accelerometer or a geophone, and the sensor installed at the wide-area seismic station is characterized as being a seismometer, and thereby the number of auxiliary seismic stations is greater than the number of wide-area seismic stations.

[0040] The auxiliary earthquake sensor, which includes a MEMS-based micro accelerometer or geophone equipped in the above-mentioned auxiliary earthquake station, has the characteristic that although its performance, such as frequency band or sensitivity, is relatively lower than that of the seismometer equipped in the above-mentioned wide-area earthquake station, it is sufficiently usable for earthquake detection and is significantly cheaper than the seismometer, so it is possible to provide an early earthquake warning by constructing multiple stations to partially supplement the earthquake detection performance.

[0041] The above-mentioned auxiliary earthquake observation station is characterized by being installed in an inland urban area with many residential and commercial districts where significant damage is judged to occur in the event of an earthquake, or in a boundary area of ​​a wide-area earthquake observation station. In the case of the above-mentioned wide-area earthquake observation station, it is installed in a boundary area between cities or a green zone where the installation site is wide, which can also be confirmed through FIGS. 4a and 4b.

[0042] FIGS. 4a and 4b are exemplary diagrams showing the locations of the auxiliary seismic observation station and the wide-area seismic observation station of the present invention. According to FIG. 4a, the high-density yellow (Pohang array) and blue (Gyeongju array) represent the locations of the auxiliary seismic observation station, and the green (KMA and KIGAM) represents the locations of the wide-area seismic observation station. According to FIG. 4b, the high-density yellow (Geophone) represents the locations of the auxiliary seismic observation station, and the light blue (KMA) represents the locations of the wide-area seismic observation station.

[0043] In addition, the aforementioned necessary institutions are characterized as being at least one of the Korea Meteorological Administration, the Korea Institute of Geoscience and Mineral Resources, Korea Hydro & Nuclear Power, and the Korea Institute of Nuclear Safety and Technology, and are also characterized as being government agencies or local government agencies or related institutions capable of providing earthquake warning notifications in addition to the institutions mentioned above.

[0044] The signal filtering unit (300) according to the present invention filters the first earthquake signal measured by the first measuring unit (100) and also filters the second earthquake signal measured by the second measuring unit (200). This serves to facilitate detection and verification in the earthquake detection unit (400) and the earthquake verification unit (500), and more specifically, means preprocessing the signals measured using sensors in the first measuring unit and the second measuring unit by filtering them so that detection and verification can be performed in the earthquake detection unit (400) and the earthquake verification unit (500).

[0045] FIG. 2 is a configuration diagram of an earthquake detection unit (400) according to one embodiment of the present invention.

[0046] As illustrated in FIG. 2, the earthquake detection unit (400) according to the present invention is characterized by including a detection module (410), a calculation module (420), a location calculation module (430), and a magnitude calculation module (440).

[0047] More specifically, the detection module (410) is a component that detects candidate P-waves among the seismic waves of the first seismic signal preprocessed in the signal filtering unit (300), and the calculation module (420) is a component that, when candidate P-waves are detected at one of the multiple auxiliary seismic stations, calculates the number of candidate P-waves measured at the multiple auxiliary seismic stations, including the auxiliary seismic station where candidate P-waves were detected, and the maximum amplitude values ​​of the auxiliary seismic stations where candidate P-waves were detected, for 2 seconds from the time of detection of candidate P-waves. Additionally, the location calculation module (430) is a component that, if the number of candidate P-waves calculated by the calculation module is greater than or equal to a reference number, estimates the location of occurrence of the first earthquake signal in which the candidate P-waves are detected and assumes the candidate P-waves as the P-waves of the first earthquake signal, and finally, the magnitude calculation module (440) is a component that calculates the magnitude of the first earthquake signal in which the P-waves are detected when the location of occurrence of the first earthquake signal is estimated by the location calculation module (430).

[0048] Specifically, when an earthquake occurs, the earthquake signal resulting from the earthquake is primarily measured at the aforementioned multiple auxiliary earthquake stations, and the earthquake is detected after detecting a candidate P-wave from the seismic wave of the first earthquake signal measured, and when the earthquake is detected, if the same earthquake signal as the first earthquake signal measured at the auxiliary earthquake station is detected in the second earthquake signal measured secondarily at the aforementioned wide-area earthquake station near the auxiliary earthquake station, it is determined that an earthquake has occurred, and the location of occurrence and magnitude of the detected earthquake are estimated and calculated, and if the magnitude of the earthquake is greater than or equal to a set threshold, an alarm notification is delivered.

[0049] According to one embodiment of the present invention, when the candidate P-wave is detected at one of the auxiliary earthquake stations among the plurality of auxiliary earthquake stations, the calculation module (420) calculates the number of candidate P-waves measured or detected at the plurality of auxiliary earthquake stations, including the auxiliary earthquake station where the candidate P-wave was detected, and the maximum amplitude values ​​of the auxiliary earthquake stations where the candidate P-waves were detected, for 2 seconds from the time when the candidate P-wave was detected by the detection module (410), i.e., the time when the candidate P-wave was detected. According to one embodiment of the present invention, the location calculation module (430) estimates the location of the occurrence of the first earthquake signal where the P-wave was detected if the number of candidate P-waves is greater than or equal to a certain reference number.

[0050] The 'number of references', which is a condition for estimating the location of the first earthquake signal in which the candidate P-wave is detected in the above location calculation module (430), is characterized by being four or more, and the location of the first earthquake signal in which the candidate P-wave is detected is characterized by being at least one of the epicenter location or the hypocenter location.

[0051] Here, if the number of candidate P-waves calculated by the position calculation module (430) is greater than or equal to a reference number, the position of the first earthquake signal in which the candidate P-waves were detected is estimated, and the candidate P-waves are assumed to be the P-waves of the first earthquake signal. Accordingly, the position calculation module (430) according to the present invention has the characteristic of detecting an earthquake that occurred primarily using the P-waves of the first earthquake signal.

[0052] Intensity and magnitude are indicators of an earthquake. Magnitude is measured on the Richter scale and is expressed as a number, while intensity is measured on the Modified Mercalli Intensity Scale and is indicated by Roman numerals. Additionally, intensity can be calculated using the maximum acceleration of seismic waves or the maximum ground acceleration.

[0053] The phenomena according to each scale and intensity can be seen in Table 1 below.

[0054] Modified Mercalli Progression scale Richter scale Phenomena by Intensity Level Ⅰ <3.4 Most people cannot feel it, but it is recorded by seismographs. Ⅱ 3.5~4.2 Only a few people in quiet conditions or on the upper floors of the building feel it. Ⅲ People inside, especially those on the upper floors of the building, noticeably feel it, and the stationary car shakes slightly. Ⅳ 4.3~4.8 Many people indoors feel it, wake up at night, and dishes and windows shake. Ⅴ 4.9~5.4 Almost everyone feels the vibrations, dishes and windows break, and unstable objects fall over. Ⅵ 5.5~6.1 Everyone feels it, some heavy furniture moves, and plaster falls off the walls. Ⅶ General buildings suffer minor damage, while poorly constructed buildings suffer significant damage. Ⅷ 6.2~6.9 Significant damage, such as partial collapse, occurs in ordinary buildings, and serious damage occurs in poorly constructed buildings. Ⅸ Even well-designed buildings suffer significant damage, and ordinary buildings experience major damage such as collapse. Ⅹ 7.0~7.3 Most stone and framed buildings are destroyed, and train tracks are bent. ⅩⅠ 7.4~7.9 Almost no structures remain, bridges have collapsed, and train tracks are severely bent. ⅩⅡ >8.0 Everything is damaged, the surface of the earth is severely distorted, and objects are flung into the air.

[0056] If the magnitude calculated by the magnitude calculation module (440) is 3 or greater, the earthquake verification unit (500) according to the present invention determines whether a P-wave corresponding to the P-wave of the first earthquake signal, whose occurrence location is estimated by the location calculation module, is detected in the second earthquake signal measured at the wide-area earthquake observation station near the auxiliary earthquake observation station selected according to a preset priority.

[0057] Here, the aforementioned prioritization is characterized in that the wide-area earthquake station located within a radius of 50 km or less from the auxiliary earthquake station where the first earthquake signal including the P wave detected by the detection module (410) was first measured is the first priority, the wide-area earthquake station located within a radius of more than 50 km and less than 100 km from the auxiliary earthquake station where the first earthquake signal including the P wave detected by the detection module (410) was first measured is the second priority, and the wide-area earthquake station located within a radius of more than 100 km from the auxiliary earthquake station where the first earthquake signal including the P wave detected by the detection module (410) was first measured is the third priority.

[0058] Accordingly, the earthquake verification unit (500) according to the present invention determines whether a P-wave corresponding to the P-wave of the first earthquake signal, whose occurrence location is estimated, is detected in the second earthquake signal measured at the first priority wide-area earthquake observation station, and performs a second verification of the earthquake detected at the auxiliary earthquake observation station. Accordingly, the present invention has the effect of increasing the reliability of the earthquake detected at the auxiliary earthquake observation station through a second verification using data acquired from the wide-area earthquake observation station capable of more precise earthquake detection.

[0059] An alarm notification unit (600) according to an embodiment of the present invention is characterized by determining that an earthquake has occurred and transmitting an earthquake alarm notification to the necessary agency when a P-wave corresponding to the P-wave of the first earthquake signal, whose occurrence location is estimated in the second earthquake signal, is detected in the earthquake verification unit (500).

[0060] A location calculation module (430) according to one embodiment of the present invention is characterized by estimating the location of occurrence of the first earthquake signal based on the quality grade of the wide-area earthquake station and the auxiliary earthquake station, wherein the quality grade is determined by measuring the real-time background noise of the wide-area earthquake station and the auxiliary earthquake station for two hours and determining the amplitude by frequency of the measured background noise. More specifically, the background noise of the wide-area earthquake station and the auxiliary earthquake station is measured for a length of two hours, and the quality grade is determined according to the amplitude by frequency of the measured background noise for a length of two hours.

[0061] Here, the quality grade is characterized in that the frequency-dependent amplitude of the measured background noise is Grade 1 if it is within the range of the new high-noise model (NHNM) and new low-noise model (NLNM) presented by McNamara and Buland (2004), and Grade 2 if it is outside the range.

[0062] More specifically, the new noise models presented by McNarama and Buland (2004) are models developed by analyzing seismic background noise measured over a long period across the United States by the U.S. Geological Survey (USGS). Since the level of noise caused by natural and human activities can be identified through the analysis of noise levels at each station, it can be concluded that stations outside the range of the high-noise model (NHNM) presented above have relatively low reliability of detected seismic signals and can only detect relatively large-magnitude earthquakes.

[0063] In addition, if the frequency-dependent amplitude of the background noise of the above-mentioned wide-area seismic observation station and the above-mentioned auxiliary seismic observation station satisfies the range of the above-mentioned high-noise model (NHNM), it can be determined that the reliability of the seismic signal detected at the observation station is high and that it is possible to detect earthquakes of various magnitudes.

[0064] The location calculation module (430) according to the present invention is characterized by calculating the time difference between the theoretical arrival time of the candidate P-wave and the actual arrival time of the candidate P-wave according to the candidate P-wave velocity at each of the auxiliary earthquake station where the first earthquake signal is measured, the auxiliary earthquake station having a quality grade of 1 within a radius of 50 km of the auxiliary earthquake station where the first earthquake signal is measured, and the wide-area earthquake station having a quality grade of 1 within a radius of 50 km of the auxiliary earthquake station where the first earthquake signal is measured, and estimating the point that minimizes the total time difference as the location of occurrence of the first earthquake signal where the candidate P-wave is detected, and assuming the candidate P-wave as the P-wave of the first earthquake signal.

[0065] Here, the auxiliary seismic station where the first seismic signal was measured is the auxiliary seismic station where the candidate P-wave of the first seismic signal was detected in the detection module.

[0066] An alarm notification unit (600) according to one embodiment of the present invention is characterized by further including an aftershock notification module (610) that generates an intensity map and provides it to the meteorological agency when the magnitude calculated by the magnitude calculation module (440) is 5 or greater, and the aftershock notification module (610) includes an aftershock detection module (611), an intensity conversion module (612), and an aftershock information provision module (613).

[0067] More specifically, the aftershock detection module (611) according to the present invention is a component that detects aftershocks that occur for 5 hours from the time the earthquake of magnitude 5 or greater occurs at an auxiliary earthquake observation station within a radius of 50 km from the epicenter of the earthquake of magnitude 5 or greater, if the magnitude calculated by the magnitude calculation module (440) is 5 or greater.

[0068] The intensity conversion module (612) according to the present invention is a component that converts the acceleration into intensity whenever an acceleration greater than the reference acceleration is measured at four or more of the auxiliary earthquake observation stations and wide-area earthquake observation stations within a radius of 50 KM from the epicenter of an aftershock of magnitude 5 or higher detected by the aftershock detection module (611), and the aftershock information provision module (613) is a component that generates an intensity map using the converted intensity and provides the aftershock detection status and the intensity map to the necessary institutions.

[0069] Accordingly, the present invention provides information on aftershocks of a large-scale earthquake to relevant agencies, thereby enabling warning notifications regarding aftershocks and having the effect of reducing the scale of earthquake damage.

[0070] FIG. 5 is a flowchart illustrating an earthquake detection method according to one embodiment of the present invention.

[0071] As illustrated in FIG. 5, the earthquake detection method utilizing a wide-area earthquake station and an auxiliary earthquake station simultaneously comprises: a step (S100) of primarily measuring a first earthquake signal through a sensor at an auxiliary earthquake station installed in an urban area or a boundary area of ​​a wide-area earthquake station at a first measurement unit (100); a step (S200) of secondarily measuring a second earthquake signal through a sensor at the wide-area earthquake station near the auxiliary earthquake station at a second measurement unit (200); a step (S300) of preprocessing the first earthquake signal at a signal filtering unit; a step (S400) of detecting an earthquake using a candidate P-wave among the seismic waves of the first earthquake signal preprocessed at the step of preprocessing the first earthquake signal at an earthquake detection unit (400); and, if the magnitude of the earthquake detected at the step of detecting an earthquake using the candidate P-wave is greater than or equal to a set threshold, a step of determining whether the first earthquake signal of the detected earthquake is detected in the second earthquake signal measured at the wide-area earthquake station near the auxiliary earthquake station. The method is characterized by including a step (S500) of verifying the earthquake detection through confirmation, and a step (S600) of transmitting an alarm to a necessary agency when the magnitude of the earthquake verified in the verification step is greater than or equal to a set threshold in the alarm notification unit (600).

[0072] Therefore, it can be seen that the present invention can shorten the time required for on-site earthquake warning notifications and early earthquake warnings by utilizing data measured from sensors installed in multiple auxiliary earthquake observation stations located in boundary areas of the wide-area earthquake observation station or in urban areas where it is difficult to secure installation sites, and has the effect of enhancing the reliability of earthquakes detected by auxiliary earthquake observation stations through feedback verification using data measured from sensors installed in the wide-area earthquake observation station.

[0073] Although the technical concept of the present invention described above has been specifically described in preferred embodiments, it should be noted that the aforementioned embodiments are for illustrative purposes only and are not intended to be limiting. Furthermore, those skilled in the art will understand that various embodiments are possible within the scope of the technical concept of the present invention. Accordingly, the true scope of technical protection of the present invention should be determined by the technical concept of the appended claims. Explanation of the symbols

[0074] 1 : Earthquake detection system 100 : First measuring part 200 : 2nd measuring part 300 : Signal filter 400 : Earthquake detection unit 500 : Earthquake Verification Department 600 : Alarm notification section 410 : Detection module 420 : Output Module 430 : Position calculation module 440 : Scale Calculation Module 610 : Aftershock Notification Module 611 : Aftershock detection module 612 : Progression Conversion Module 613 : Aftershock Information Provision Module

Claims

Claim 1 A first measurement unit that primarily measures a first earthquake signal through sensors at a plurality of auxiliary earthquake stations installed in an urban area or at the boundary of a wide-area earthquake station; a second measurement unit that secondarily measures a second earthquake signal through sensors at a wide-area earthquake station near the auxiliary earthquake station; a signal filtering unit that preprocesses the first earthquake signal; an earthquake detection unit that detects an earthquake using candidate P-waves among the seismic waves of the first earthquake signal preprocessed by the signal filtering unit; an earthquake verification unit that verifies the earthquake detection by confirming whether the first earthquake signal of the detected earthquake is detected in the second earthquake signal measured at the wide-area earthquake station near the auxiliary earthquake station when the magnitude of the detected earthquake is greater than or equal to a set threshold; and an alarm notification unit that transmits an alarm to a necessary agency when the verified magnitude of the earthquake is greater than or equal to a set threshold; wherein the earthquake detection unit includes a detection module that detects candidate P-waves among the seismic waves of the first earthquake signal preprocessed by the signal filtering unit; A seismic detection system utilizing a wide-area seismic station and an auxiliary seismic station simultaneously, characterized by comprising: a calculation module that, when a candidate P-wave is detected at one of the plurality of auxiliary seismic stations in the detection module, calculates the number of candidate P-waves measured at the plurality of auxiliary seismic stations including the auxiliary seismic station where the candidate P-wave was detected, and the maximum amplitude values ​​of the auxiliary seismic stations where the candidate P-waves were detected, for 2 seconds from the time of detection of the candidate P-wave; a location calculation module that, if the number of candidate P-waves calculated by the calculation module is greater than or equal to a reference number, estimates the location of the occurrence of the first seismic signal where the candidate P-wave was detected and assumes the candidate P-waves as the P-waves of the first seismic signal; and a magnitude calculation module that, when the location of the occurrence of the first seismic signal is estimated by the location calculation module, calculates the magnitude of the first seismic signal where the P-wave was detected. Claim 2 A seismic detection system utilizing both a wide-area seismic station and an auxiliary seismic station simultaneously, characterized in that, in claim 1, the number of the auxiliary seismic station is greater than the number of the wide-area seismic station. Claim 3 A seismic detection system utilizing a wide-area seismic station and an auxiliary seismic station simultaneously, wherein, in claim 1, the seismic signal is characterized as being at least one of the type, amplitude, velocity, and acceleration information of a seismic wave, the type of the seismic wave is characterized as being a P-wave, the sensor installed at the auxiliary seismic station is characterized as being at least one of an auxiliary seismic sensor including a MEMS-based micro accelerometer sensor or a geophone, and the sensor installed at the wide-area seismic station is characterized as being a seismometer. Claim 4 delete Claim 5 In claim 1, the earthquake verification unit determines whether a P-wave corresponding to the P-wave of the first earthquake signal, whose occurrence location is estimated by the location calculation module, is detected in the second earthquake signal measured at the wide-area earthquake observation station near the auxiliary earthquake observation station selected according to a preset priority if the magnitude calculated by the magnitude calculation module is 3 or greater, thereby forming an earthquake detection system that simultaneously utilizes a wide-area earthquake observation station and an auxiliary earthquake observation station. Claim 6 In claim 5, the earthquake detection system utilizing a wide-area earthquake observation station and an auxiliary earthquake observation station simultaneously is characterized in that the alarm notification unit determines that an earthquake has occurred and transmits an earthquake alarm notification to the necessary agency when a P-wave corresponding to the P-wave of the first earthquake signal, whose occurrence location is estimated in the second earthquake signal, is detected by the earthquake verification unit. Claim 7 A seismic detection system utilizing a wide-area seismic station and an auxiliary seismic station simultaneously, characterized in that, in claim 6, the previously set priority is a wide-area seismic station located within a radius of 50 km or less from the auxiliary seismic station where the first seismic signal including the candidate P-wave detected by the detection module was first measured, a wide-area seismic station located within a radius of more than 50 km and less than or equal to 100 km from the auxiliary seismic station where the first seismic signal including the P-wave detected by the detection module was first measured, a wide-area seismic station located within a radius of more than 100 km from the auxiliary seismic station where the first seismic signal including the P-wave detected by the detection module was first measured, a wide-area seismic station located within a radius of more than 100 km from the auxiliary seismic station where the first seismic signal including the P-wave detected by the detection module was first measured. Claim 8 In claim 7, the earthquake verification unit is characterized by determining whether a P-wave corresponding to the P-wave of the first earthquake signal, whose occurrence location is estimated, is detected in the second earthquake signal measured at the first-priority wide-area earthquake observation station, in a seismic detection system utilizing both a wide-area earthquake observation station and an auxiliary earthquake observation station simultaneously. Claim 9 A seismic detection system utilizing a wide-area seismic station and an auxiliary seismic station simultaneously, wherein, in claim 1, the location calculation module estimates the location of occurrence of the first seismic signal based on the quality grade of the wide-area seismic station and the auxiliary seismic station, and the quality grade is determined according to the amplitude by frequency of the measured background noise by measuring real-time background noise of the wide-area seismic station and the auxiliary seismic station for two hours. Claim 10 A seismic detection system utilizing a wide-area seismic station and an auxiliary seismic station simultaneously, characterized in that, in claim 9, the quality grade is Grade 1 if the frequency-dependent amplitude of the measured background noise is within the range of the high-noise model (HNM) and low-noise model (LHM) presented by McNamara and Buland (2004), and Grade 2 if it is outside the range. Claim 11 In claim 10, the location calculation module calculates the time difference between the theoretical arrival time of the candidate P-wave and the actual arrival time of the candidate P-wave according to the candidate P-wave velocity at each of the auxiliary seismic station where the first seismic signal is measured, the auxiliary seismic station having a quality grade of Grade 1 within a radius of 50 km of the auxiliary seismic station where the first seismic signal is measured, and the wide-area seismic station having a quality grade of Grade 1 within a radius of 50 km of the auxiliary seismic station where the first seismic signal is measured, estimates the point that minimizes the total time difference as the location of occurrence of the first seismic signal where the candidate P-wave is detected, and assumes the candidate P-wave as the P-wave of the first seismic signal, thereby forming a seismic detection system that simultaneously utilizes a wide-area seismic station and an auxiliary seismic station. Claim 12 An earthquake detection system utilizing a wide-area earthquake observation station and an auxiliary earthquake observation station simultaneously, characterized in that, in claim 1, the alarm notification unit further includes an aftershock notification module that generates an intensity map and provides it to the necessary agency if the magnitude calculated by the magnitude calculation module is 5 or greater. Claim 13 In claim 12, the aftershock notification module comprises: an aftershock detection module that detects aftershocks occurring for 5 hours from the time an earthquake of magnitude 5 or greater occurs at an auxiliary earthquake station within a radius of 50 km from the epicenter of an earthquake of magnitude 5 or greater if the magnitude calculated by the magnitude calculation module is 5 or greater; an intensity conversion module that converts acceleration equal to a reference acceleration whenever acceleration equal to or greater than a reference acceleration is measured at four or more of the auxiliary earthquake stations and the wide-area earthquake stations within a radius of 50 km from the epicenter of an aftershock of magnitude 5 or greater detected by the aftershock detection module; and an aftershock information provision module that generates an intensity map using the converted intensity and provides the aftershock detection status and the intensity map to the necessary agency; thereby forming an earthquake detection system that simultaneously utilizes wide-area earthquake stations and auxiliary earthquake stations. Claim 14 delete

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