KR101034537B1 - Device for sensing-correcting a earthquake signal and drive method of the same - Google Patents

Abstract

PURPOSE: A device for sensing and compensating an earthquake signal is provided to reduce a signal sensing error by filtering a noise. CONSTITUTION: An earthquake sensor(100) measures a first slope of an earthquake signal sensing and compensating device and automatically measures a second slope that is a current slope value. A first operating unit(200) compensates an original earthquake sensing signal by subtracting the second slope from the first slope and multiplying the subtracted result with a slope compensation constant. A low pass filter(300) processes the low pass filtering of the received earthquake sensing signal. A second operating unit(400) produces a noise signal by FFT(Fast Fourier Transform) and integration operation of the filtered earthquake sensing signal, extracts a natural frequency about a structure from the noise signal, and extracts a displacement value and an amplification rate about the structure in the natural frequency.

Description

Device for Sensing-correcting a Earthquake Signal and Drive Method of the Same}

The present invention relates to a control measurement technique, and in particular, it effectively filters the noise signal included in the seismic detection source signal detected at the time of earthquake, and automatically corrects the change of the slope when the slope changes of the structure, thereby significantly reducing the signal detection error. The present invention relates to an earthquake signal detection and correction device for reducing and obtaining a very stable pure earthquake detection signal and a driving method thereof.

In general, an earthquake occurs when seismic forces continue to act on parts of the earth's crust, causing the seismic waves to reach the ground caused by the sudden release of elastic, chemical, and gravitational energy gathered locally at this point. The magnitudes range from very small earthquakes detected only by sensitive seismographs to large earthquakes that can cause extensive damage.

Thousands of earthquakes occur on Earth every day around the world. Most earthquakes are caused by large forces within the Earth that act over long periods of time, such as continental movement, seabed expansion, and mountain range formation. In addition, volcanic activity causes earthquakes, but in this case they are relatively small. In addition, an earthquake can be artificially generated by explosives.

The earthquake detection signal includes noise signals of various irregular patterns. When a conventional earthquake signal detection device installed in a structure is installed between high-rise buildings, the earthquake detection signal measured by the earthquake signal detection device is a pedestrian walking pattern. If installed on a high-rise roof, it is affected by the natural frequency of the building.

As such, the conventional earthquake signal detecting device has a problem in that the original signal of the state in which the filtering of the noise signal is not performed is misjudged as the earthquake detection signal, so it is difficult to identify an accurate earthquake detection signal only by the earthquake.

In other words, the conventional earthquake signal detecting device has a problem that it is not easy to extract only the unique earthquake signal due to the earthquake due to the fact that the seismic signal mixed with various types of noise can be detected and measured.

In addition, the conventional seismic signal detection device by applying a short term average (STA), a long term average (LTA) by software to determine the suitability of the earthquake signal from which the noise is removed, but after processing the earthquake signal mixed with noise There is a possibility that a signal having a very long period of signal pattern and displacement in a resonance state may be misjudged as an earthquake signal, and an earthquake signal detected by an earthquake as well as noise to be removed may be inadvertently removed. There is this.

In addition, the conventional seismic signal detecting apparatus cannot accurately extract the seismic signal detected due to the earthquake because it does not consider the unique characteristics of each structure in analyzing and filtering the seismic signal mixed with various types of noise. Has a problem.

The seismic signal detection and correction method of the present invention and its driving method have been devised to solve the problems of the prior art, the first object of the present invention is to effectively detect the noise signal included in the earthquake detection source signal detected during the earthquake The filter process greatly reduces signal detection errors and obtains a very stable pure earthquake detection signal.

In addition, a second object of the present invention is to obtain a pure earthquake detection signal with higher accuracy by automatically performing correction according to the change of the slope when the slope change of the structure due to the earthquake occurs.

In addition, the third object of the present invention is to extract a more accurate pure earthquake detection signal, thereby minimizing the occurrence of earthquake alarms caused by the detection of inaccurate earthquake detection signal unambiguously, thereby eliminating unnecessary waste of manpower To save.

In addition, the fourth object of the present invention is to obtain more accurate earthquake related data when an earthquake occurs, thereby providing a foundation for proactively preventing social confusion caused by earthquake disasters so as to greatly contribute to the expansion of social stability network and national interests. To do this.

The present invention for achieving the above object includes the following configuration.

That is, the earthquake signal detection and correction device according to an embodiment of the present invention, when the initial installation on the structure automatically measures the first tilt sensitivity value, and caused by the earthquake detection source signal detected by the earthquake and the earthquake occurrence An earthquake detection sensor for automatically measuring a second tilt sensitivity value indicating a current tilt value of the structure; A first calculation unit which calculates a correction value by multiplying a result obtained by subtracting the first slope sensitivity value by a second slope sensitivity value by a preset slope correction constant, and then generates an earthquake detection signal obtained by subtracting the correction value from the earthquake detection source signal; A low pass filter configured to generate an earthquake detection LPF signal having only a frequency component lower than a preset cut-off frequency according to the low pass filtering of the received earthquake detection signal; Fast Fourier transform and integrating the earthquake detection LPF signal to obtain a noise signal contained in the earthquake detection LPF signal, and extract the natural frequency of the structure from the noise signal, as well as the intrinsic structure of the structure A second calculator extracting an amplification degree and a displacement value of the structure from a frequency; A FIR filter for generating a pure earthquake detection signal from which the noise signal is removed by digitizing and fast filtering the earthquake detection LPF signal; And analyzing the signal pattern of the pure earthquake detection signal in time series to determine whether the pure earthquake detection signal is an instant signal or an earthquake wave, and when the pure earthquake detection signal turns out to be the earthquake wave in the determination, the pure earthquake And a determination controller for outputting a detection signal.

In addition, the method of driving the seismic signal detection and correction device according to an embodiment of the present invention, when the earthquake detection sensor is initially installed on the structure automatically measures the first tilt sensitivity value, the earthquake detection source signal detected by the earthquake occurrence And automatically measuring a second slope sensitivity value indicating a current slope value of the structure caused by the earthquake. Generating a correction value by subtracting the correction value from the seismic detection source signal by calculating a correction value by multiplying a result obtained by subtracting the first slope sensitivity value from the first slope sensitivity value by a preset slope correction constant; Generating a seismic detection LPF signal composed of only frequency components lower than a preset cut-off frequency as the lowpass filter performs lowpass filtering on the received seismic detection signal; Obtaining, by a second calculator, a noise signal included in the earthquake detection LPF signal by performing fast Fourier transform and integrating the earthquake detection LPF signal; Extracting, by the second calculation unit, natural frequencies for the structure from the noise signal, as well as extracting amplification degree and displacement values for the structure from natural frequencies of the structure; Generating a pure earthquake detection signal from which the noise signal is removed as a FIR filter digitizes and performs high-speed filtering of the earthquake detection LPF signal; And determining, by the determination controller, whether the pure earthquake detection signal is an instant signal or an earthquake wave by analyzing the signal pattern of the pure earthquake detection signal in time series. And outputting the pure earthquake detection signal when the determination controller determines the pure earthquake detection signal as the seismic wave.

The seismic signal detection and correction method of the present invention and its driving method are the first to effectively reduce the signal detection error and obtain a very stable pure earthquake detection signal by effectively filtering the noise signal contained in the seismic detection source signal detected at the time of earthquake occurrence Give effect.

In addition, the present invention provides a second effect of obtaining a pure earthquake detection signal with higher accuracy by automatically performing correction according to the change of the slope when the structure changes due to the earthquake.

In addition, the present invention extracts a more accurate pure earthquake detection signal, thereby minimizing the occurrence of earthquake alarms caused by the detection of inaccurate earthquake detection signal unambiguously, thereby reducing the unnecessary waste of human resources Give effect.

In addition, the present invention obtains more accurate earthquake-related data in the event of an earthquake, thereby providing a foundation for proactively avoiding social disruption due to earthquake disasters, thereby expanding the social stability network and making a significant contribution to national interests. Gives.

1 is a view showing an earthquake signal detection and correction apparatus according to an embodiment of the present invention.
Figure 2 is a graph showing the earthquake detection source signal detected from the earthquake signal detection and correction device according to an embodiment of the present invention.
3 is a graph illustrating a signal in which an earthquake detection LPF signal is sampled by a fast Fourier transform according to an embodiment of the present invention.
4 is a graph showing a pure earthquake detection signal finally detected by the earthquake signal detection and correction device according to an embodiment of the present invention.
5 is a flowchart illustrating a method of driving an earthquake signal detection and correction device according to an embodiment of the present invention.

[Example]

Hereinafter, described in detail with reference to the accompanying drawings an embodiment of the present invention.

1 is a view showing an earthquake signal detection and correction apparatus according to an embodiment of the present invention.

Referring to FIG. 1, the seismic signal detection and correction apparatus 1000 not only effectively filters the noise signal included in the seismic detection source signal detected when an earthquake occurs, but also automatically performs correction according to the change of the slope when the slope of the structure changes. It is a device that greatly reduces the signal detection error and obtains a very stable pure earthquake detection signal. The earthquake detection sensor 100, the first calculation unit 200, the low pass filter 300, the second calculation unit 400, and the FIR filter ( 500 and the determination controller 600.

In addition, the seismic signal detection and correction apparatus 1000 of the present invention can more accurately grasp the noise signal including the unique characteristic value (that is, the natural frequency of the structure) for each structure, it is detected by the earthquake generation Only seismic signals can be extracted more clearly.

The earthquake detection sensor 100 automatically measures the first tilt sensitivity value to the structure itself when the earthquake signal detection and correction device 1000 is installed on the structure, and detects the earthquake detection source signal detected by the earthquake. And a second slope sensitivity value indicating a current slope value of the changed structure caused by the earthquake.

That is, the earthquake detection sensor 100 includes a first seismograph and a second seismograph, and the first seismograph automatically displays the first slope sensitivity value and the second slope sensitivity value indicating the current slope value of the structure caused by the earthquake. Measure

In addition, the second seismograph measures and generates an earthquake detection source signal detected by the earthquake, as shown in FIG.

The first calculating unit 200 calculates a correction value by multiplying a result obtained by subtracting the first tilt sensitivity value from the second tilt sensitivity value by a preset slope correction constant, and then generates an earthquake detection signal obtained by subtracting the correction value from the original earthquake detection source signal.

The earthquake detection signal can be obtained by substituting [Equation 1] into [Equation 2].

The low pass filter 300 generates an earthquake detection LPF signal composed of only frequency components lower than a preset cut-off frequency as the low pass filtering of the received earthquake detection signal is performed.

The low pass filter 300 has a basic configuration in which the resistance is in series and the capacitor is in parallel with respect to the operational amplifier in a circuit, and passes only a frequency band lower than a preset cut-off frequency and attenuates a higher frequency band. Cut off filter.

The low pass filter 300 is a filter that is uniformly used in all fields such as the purpose of removing low frequency ripple from the power supply unit, the purpose of removing high frequency spurious, the suppression of high frequency and various detections.

As an example, the voltage across the capacitor goes out to the part where the impedance (Z = 1 / = 1 / 2π * cut-off frequency) becomes higher as the frequency increases. In this way, the capacitors are connected in parallel Smooth out the output value (i.e. seismic detection LPF signal) by eliminating high frequency ripple noise mixed with the signal (i.e. seismic detection signal).

That is, the earthquake detection LPF signal C according to the embodiment of the present invention can be obtained by substituting the low pass intermediate calculation value g obtained through Equation 3 into Equation 4.

Where A is an earthquake detection source signal, B is an earthquake detection signal, C 'is an earthquake detection LPF signal on the previous step, and g is an arbitrary low pass intermediate calculation value.

Note that the cut-off frequency is at least one value selected within the 55 Hz to 65 Hz frequency band.

The second operation unit 400 obtains a noise signal included in the earthquake detection LPF signal by performing fast Fourier transform (FFT) and integral operation on the earthquake detection LPF signal, and extracts the natural frequency of the structure from the noise signal. Instead, the amplification and displacement values of the structure are extracted from the natural frequencies of the structure.

In general, the fast Fourier transform (FFT) is not designed to convert all of the earthquake detection LPF signal in the designed method because the Discrete Fourier transform (DFT) takes too long to calculate, but in FIG. As can be seen, it is a high-speed conversion by selecting and minimizing only necessary signals in sampling form.

The second operation unit 400 sets the average value of the repetition frequency range that appears repeatedly at least once on the noise signal as the natural frequency of the structure, and amplifies the displacement and the displacement value of the structure numerically by analyzing the natural frequency of the structure. Obtain

Here, the natural frequency of the structure is the interference occurring in the structure itself, and the natural earthquake detection signal can be finally obtained only by understanding the natural frequency of the structure included in the noise signal, and thus the natural frequency of the structure is obtained. Therefore, the amplification degree and displacement value for the structure can be obtained further.

The finite impulse response (FIR) filter digitizes and performs high-speed filtering of the earthquake detection LPF signal, thereby generating a pure earthquake detection signal from which the noise signal is removed as shown in FIG. 4.

At this time, it is noted that the FIR filter 500 performs a high speed filtering process on the earthquake detection LPF signal at a speed of 1 to 2 kHz.

The FIR filter 500 performs digitizing and fast filtering by filtering only fixed (finite, finite) values of the earthquake detection LPF signal, and has a finite length when the impulse response, which is a characteristic function of the filter, is obtained. Because it does not have a feedback component, it plays a very important role in maintaining the pure seismic signal waveform from which the noise signal is removed.

For reference, the FIR filter 500 design method includes a window method, a frequency sampling method, a computer-based optimal design method, and the like.

Finally, the determination controller 600 analyzes the signal pattern of the pure earthquake detection signal in time series to determine whether the pure earthquake detection signal is an instant signal or an earthquake wave, and when the pure earthquake detection signal is determined to be an earthquake wave in the judgment. Outputs pure earthquake detection signal.

5 is a flowchart illustrating a method of driving an earthquake signal detection and correction device according to an embodiment of the present invention.

Referring to FIG. 5, the method of driving an earthquake signal detection and correction device not only effectively filters noise signals included in the earthquake detection source signal detected when an earthquake occurs, but also automatically performs correction according to a slope change when a slope of a structure changes. This method greatly reduces signal detection errors and obtains a very stable pure earthquake detection signal.

First, the earthquake detection sensor is initially installed on the structure and then automatically measures the first tilt sensitivity value (S10), and a second earthquake detection source signal detected by the earthquake and the second slope indicating the current slope value of the structure caused by the earthquake. The tilt sensitivity value is automatically measured (S20).

That is, the first seismograph installed in the earthquake detection sensor automatically measures the first slope sensitivity value and the second slope sensitivity value indicating the current slope value of the structure caused by the earthquake as it is initially installed on the structure. Seismograph measures and generates seismic detection source signal detected by the earthquake.

After calculating the correction value by multiplying a result obtained by subtracting the first slope sensitivity value from the second slope sensitivity value by a preset slope correction constant, the first calculator generates an earthquake detection signal obtained by subtracting the correction value from the original earthquake detection source signal (S30, S40). .

The low pass filter generates an earthquake detection LPF signal composed of only frequency components lower than the preset cut-off frequency according to the low pass filtering of the received earthquake detection signal (S50 and S60).

The second calculating unit obtains a noise signal included in the earthquake detection LPF signal by performing fast Fourier transform and integral operation on the earthquake detection LPF signal (S70 and S80).

The second calculating unit sets the average value of the repetitive frequency range repeatedly appearing at least once on the noise signal as the natural frequency of the structure, and calculates the amplification degree and the displacement value of the structure by numerically analyzing the natural frequency of the structure.

That is, the second calculator not only extracts the natural frequency of the structure from the noise signal but also extracts the amplification degree and the displacement value of the structure from the natural frequency of the structure (S90 and S100).

As the FIR filter digitizes and performs high-speed filtering of the earthquake detection LPF signal, a pure earthquake detection signal from which the noise signal is removed is generated (S110 and S120).

At this time, the FIR filter performs a high speed filtering process on the earthquake detection LPF signal at a speed of 1 to 2 kHz.

The determination controller analyzes the signal pattern of the pure earthquake detection signal in time series to determine whether the pure earthquake detection signal is an instant signal or an earthquake wave (S130 and S140).

The determination controller outputs the pure earthquake detection signal when it is determined that the pure earthquake detection signal is an earthquake wave (S150).

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be able to variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. It will be appreciated.

1000: earthquake signal detection and correction device
100: earthquake detection sensor 200: first operation unit
300: low pass filter 400: second calculation unit
500: FIR filter 600: judgment control unit

Claims (10)

An earthquake that automatically measures a first slope sensitivity value upon initial installation on a structure, and automatically measures a second slope sensitivity value representing an earthquake detection source signal detected by an earthquake occurrence and a current slope value of the structure caused by the earthquake occurrence Detection sensor;
A first calculation unit which calculates a correction value by multiplying a result obtained by subtracting the first slope sensitivity value by a second slope sensitivity value by a preset slope correction constant, and then generates an earthquake detection signal obtained by subtracting the correction value from the earthquake detection source signal;
A low pass filter configured to generate an earthquake detection LPF signal having only a frequency component lower than a preset cut-off frequency according to the low pass filtering of the received earthquake detection signal;
Fast Fourier transform and integrating the earthquake detection LPF signal to obtain a noise signal contained in the earthquake detection LPF signal, and extract the natural frequency of the structure from the noise signal, as well as the intrinsic structure of the structure A second calculator extracting an amplification degree and a displacement value of the structure from a frequency;
A FIR filter for generating a pure earthquake detection signal from which the noise signal is removed by digitizing and fast filtering the earthquake detection LPF signal; And
Analyzing the signal pattern of the pure earthquake detection signal in time series to determine whether the pure earthquake detection signal is an instant signal or an earthquake wave, and when the pure earthquake detection signal turns out to be the earthquake wave, the pure earthquake detection signal is determined. Earthquake signal detection and correction apparatus comprising a determination control unit for outputting a signal.
The method of claim 1, wherein the FIR filter,
Earthquake detection and correction device characterized in that the high-speed filtering process the seismic detection LPF signal at a speed of 1 to 2 kHz.
The method of claim 1, wherein the second operation unit,
Set an average value of the repetition frequency range that appears repeatedly at least once on the noise signal as the natural frequency of the structure, and obtain the amplification degree and the displacement value of the structure by numerically analyzing the natural frequency of the structure. Earthquake signal detection and correction device.
The method of claim 1, wherein the earthquake detection sensor,
A first seismometer for automatically measuring a first tilt sensitivity value and a second tilt sensitivity value representing a current tilt value of the structure caused by the earthquake occurrence; And
And a second seismometer for measuring and generating an earthquake detection source signal detected by the earthquake.
The method of claim 1, wherein the cut-off frequency,
Earthquake signal detection and correction device, characterized in that at least one value selected within the frequency band 55 Hz to 65 Hz.
The method of claim 1, wherein the earthquake detection LPF signal (C),

And

You can get it by
A is an earthquake detection source signal, B is the earthquake detection signal, C 'earthquake detection LPF signal on the previous step and g is an earthquake signal detection and correction device, characterized in that any low pass intermediate calculation value.
When the earthquake detection sensor is initially installed on the structure, the first slope sensitivity value is automatically measured, and the second slope sensitivity indicating the seismic detection source signal detected by the earthquake and the current slope value of the structure caused by the earthquake. Measuring the value automatically;
Generating a correction value by subtracting the correction value from the seismic detection source signal by calculating a correction value by multiplying a result obtained by subtracting the first slope sensitivity value from the first slope sensitivity value by a preset slope correction constant;
Generating a seismic detection LPF signal composed of only frequency components lower than a preset cut-off frequency as the lowpass filter performs lowpass filtering on the received seismic detection signal;
Obtaining, by a second calculator, a noise signal included in the earthquake detection LPF signal by performing fast Fourier transform and integrating the earthquake detection LPF signal;
Extracting, by the second calculation unit, natural frequencies for the structure from the noise signal, as well as extracting amplification degree and displacement values for the structure from natural frequencies of the structure;
Generating a pure earthquake detection signal from which the noise signal is removed as a FIR filter digitizes and performs high-speed filtering of the earthquake detection LPF signal; And
Determining, by the determination controller, the signal pattern of the pure earthquake detection signal in time series to determine whether the pure earthquake detection signal is an instant signal or an earthquake wave; And
And outputting the pure earthquake detection signal when the determination controller determines the pure earthquake detection signal as the seismic wave.
The method of claim 7, wherein
The FIR filter further comprises the step of high-speed filtering the seismic detection LPF signal at a speed of 1 to 2 kHz.
The method of claim 7, wherein
Setting, by the second computing unit, an average value of a repetitive frequency range repeatedly appearing at least once on the noise signal as a natural frequency of the structure;
And a second calculation unit numerically analyzing the natural frequency of the structure to obtain an amplification degree and a displacement value of the structure.
The method of claim 7, wherein the instrument in the earthquake detection sensor,
Automatically measuring a first inclination sensitivity value and a second inclination sensitivity value indicating a current inclination value of the structure caused by the earthquake as a first seismometer is initially installed on the structure; And
And measuring and generating a seismic detection source signal detected by the earthquake by a second seismometer.

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