CN111751037B

CN111751037B - Electric measurement explosion test data compression method

Info

Publication number: CN111751037B
Application number: CN202010422403.0A
Authority: CN
Inventors: 邓国强
Original assignee: National Academy of Defense Engineering of PLA Academy of Military Science
Current assignee: National Academy of Defense Engineering of PLA Academy of Military Science
Priority date: 2020-05-15
Filing date: 2020-05-15
Publication date: 2021-08-31
Anticipated expiration: 2040-05-15
Also published as: CN111751037A

Abstract

The invention relates to an electric measurement explosion test data compression method, and belongs to the technical field of protection engineering. The test data compression method comprises the following steps: step 1, representing tested test data by using a time sequence; step 2, converting the one-dimensional array of the time sequence into a two-dimensional array; step 3, obtaining the maximum value and the minimum value of the time sequence; step 4, setting an allowable error including the final precision of the control compression; step 5, judging whether the distance between each sampling point and the adjacent sampling point is smaller than a threshold value or not, and if so, discarding the sampling point; and 6, storing the residual sampling points into a new two-dimensional value, namely finishing the data compression process. According to the method, the compression percentage of the original data and the compressed data can reach 4%, and the efficiency is extremely high; the testing precision of the original data is maintained, and repeated or useless parts are discarded in the compression; the method can be embedded into various data acquisition software systems, and the algorithm is brief and easy to realize.

Description

Electric measurement explosion test data compression method

Technical Field

The invention relates to an electric measurement explosion test data compression method, and belongs to the technical field of protection engineering.

Background

The explosion wave generally has short action time and high peak value, the time resolution of the required electric measuring instrument is high, along with the development of electronic technology, the time interval of sampling points of the instrument is smaller and smaller, the requirement of test precision is met, meanwhile, the inevitably brought test data is huge, one acquisition curve has the stored data volume of tens of megabytes or even hundreds of megabytes, the test acquisition curve of one shot number generally has dozens of data, the storage scale of the test acquisition curve is up to dozens of gigabytes, although the computer technology and the storage technology are well developed at present, the huge data still brings a series of difficulties for subsequent data processing and the like, a certain technology must be adopted, and the compression is carried out on the premise of keeping the curve precision.

The explosion waveform is characterized by short action time and pulse type action, and the curve changes very slowly or does not change before the explosion wave arrives or after the explosion wave acts, which is obviously different from loads such as earthquake and the like. Aiming at the characteristic, the inventor provides a novel compression method for data of an electrical explosion test.

Disclosure of Invention

The invention aims to solve the problems that a series of difficulties are brought to subsequent data processing by super-huge explosion measurement data quantity, and the compression cannot be carried out on the premise of keeping curve precision, and provides an electric measurement explosion test data compression method which adopts detection by measuring points and comparison with the measuring points in front and at the back, if no change or change is only minimal disturbance caused by the environment but not caused by explosion waves, the measuring points are abandoned, and finally new test data is formed; because only the repeated data is discarded, the precision of the original test data is basically maintained.

The compression method of the electrical explosion test data comprises the following steps:

step 1, representing tested test data by using a time sequence, and particularly representing the time sequence by using a one-dimensional array;

P＝(p₁,p₂,p₃,…,p_n) (1)

wherein, P is a time sequence, the number of sampling points is n, P_iAt a time t_iA test value of (d);

step 2, converting the one-dimensional array of the time sequence in the step 1 into a two-dimensional array;

P(p,t)＝[(p₁,t₁),(p₂,t₂),……,(p_n,t_n)] (2)

wherein p is_nAt a time t_nValue tested, (p)_i,t_i) I.e. the ith sample point;

step 3, obtaining the maximum value and the minimum value of the time sequence in the step 1;

P_maxand P_minMaximum and minimum values of the time series, respectively;

step 4, setting an allowable error including the final precision of the control compression;

ε＝δ·|P_max-P_min| (4)

wherein, the tolerance error is marked as epsilon; delta is a given small value, e.g. 10^-6The value controlling the maximum of compressionFinal precision;

step 5, setting j from 2 to n-1, and judging whether all sampling points meet | p_j-p_j-1< ε, and | p_j-p_j+1If | < epsilon, abandoning the sampling point P if satisfied_j；

And 6, storing the residual sampling points into a new two-dimensional value, namely finishing the data compression process.

Advantageous effects

The invention provides an electric measurement explosion test data compression method, which has the following beneficial effects compared with the existing compression method:

1. the method completely provides a new compression technology of the data of the electrical measurement explosion test from principle and algorithm to application; from the specific example data, the compression percentage of the original data and the compressed data can reach 4%, and the efficiency is extremely high;

2. the method maintains the testing precision of the original data, and the discarded parts in the compression are repeated or useless parts;

3. the method can be embedded into various data acquisition software systems, has brief introduction of the algorithm and is easy to realize.

Drawings

FIG. 1 is a schematic illustration of a method of electrically measuring detonation test data compression in accordance with the present invention;

FIG. 2 is a schematic illustration of an exemplary detonation wave shape for an electrical test detonation test data compression method of the present invention;

FIG. 3 is a data graph of observation point 10 waveform of the electrical measurement explosion test data compression method, output by B-spline smoothing processing.

Detailed Description

The compression method of the electrical explosion test data is explained in detail below with reference to specific embodiments and the accompanying drawings.

Example 1

In the specific implementation of step 1, taking pressure as an example:

P＝(p₁,p₂,p₃,…,p_n) (5)

wherein, P is a pressure time sequence, the number of sampling points is n, P_iAt a time t_iThe test pressure of (a);

FIG. 2 is a schematic diagram of a typical blast wave shape of an electrical test blast test data compression method of the present invention.

For a certain shot explosion test, 20 effective explosion waveforms are obtained, the data volume before and after compression is shown in the following table 1, and most of data are compressed to 4% of original data from the table 1. But the waveform accuracy is substantially consistent with the raw data.

TABLE 1 comparison of data volumes before and after compression

FIG. 3 is a waveform of test point 10 (output with B-spline smoothing).

The explosion waveform comprises an air shock wave, an explosion stress wave, an acceleration curve, a curve and other time curve curves. Can be embedded into various data acquisition software systems.

The above-mentioned embodiments are only preferred embodiments of the present invention, and are not intended to limit the embodiments of the present invention, and those skilled in the art can easily make various changes and modifications according to the main concept and spirit of the present invention, so the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. An electric measurement explosion test data compression method is characterized in that: the method comprises the following steps:

step 1, representing tested experimental data by a time sequence,

wherein the number of sampling points is n;

ε＝δ·|P_max-P_min| (1)

wherein, the tolerance error is marked as epsilon; δ is a given small value that controls the final precision of the compression;

2. The method for compressing data of an electrical test explosion test according to claim 1, wherein the method comprises the following steps: step 1 is expressed by adopting a one-dimensional array:

P＝(p₁,p₂,p₃,…,p_n) (2)

wherein, P is a time sequence, the number of sampling points is n, P_iAt a time t_iThe test value of (1).

3. The method for compressing data of an electrical test explosion test according to claim 1, wherein the method comprises the following steps: the two-dimensional array converted in the step 2 is as follows:

P(p,t)＝[(p₁,t₁),(p₂,t₂),……,(p_n,t_n)] (3)

wherein p is_nAt a time t_nValue tested, (p)_i,t_i) I.e. the ith sample point.

4. The method for compressing data of an electrical test explosion test according to claim 1, wherein the method comprises the following steps: step 3 obtains the maximum and minimum values of the time series in step 1:

P_maxand P_minRespectively the maximum and minimum values of the time series.