阅读说明：本技术 一种海水放射性核素干扰频率的判断方法 (Method for judging interference frequency of seawater radionuclide ) 是由 程岩 张颖颖 吴丙伟 刘东彦 侯广利 张颖 冯现东 于 2020-04-17 设计创作，主要内容包括：本发明属于海水检测技术领域,涉及一种海水放射性核素干扰频率的判断方法。该方法包括以下步骤：(1)根据放射性检测仪器采集的能量信号进行傅里叶变换,生成功率谱；(2)设定基频段,针对放射性检测仪器所对应的频谱数据,遍历所述的基频段的每个频率点；(3)对于基频段中每一个存在能量的频率H,依次判断该频率所对应的2倍频处、3倍频处是否有能量存在,如果存在,则判定频率H为放射性核素的干扰频率。本发明的海水放射性核素干扰频率的判断方法不受累积时间的限制,也不受海洋环境干扰的限制,能够识别出海水放射性核素的干扰频率,可以提高计算的准确度。(The invention belongs to the technical field of seawater detection, and relates to a method for judging interference frequency of a seawater radionuclide. The method comprises the following steps: (1) performing Fourier transform according to the energy signal collected by the radioactivity detecting instrument to generate a power spectrum; (2) setting a basic frequency band, and traversing each frequency point of the basic frequency band aiming at the frequency spectrum data corresponding to the radioactivity detecting instrument; (3) and for each frequency H with energy in the fundamental frequency band, sequentially judging whether energy exists at a frequency multiplication part 2 and a frequency multiplication part 3 corresponding to the frequency, and if so, judging that the frequency H is the interference frequency of the radionuclide. The method for judging the interference frequency of the seawater radionuclide is not limited by accumulation time and ocean environment interference, can identify the interference frequency of the seawater radionuclide, and can improve the calculation accuracy.)

1. A method for judging interference frequency of seawater radionuclide is characterized by comprising the following steps: the method comprises the following steps:

(1) performing Fourier transform according to the energy signal collected by the radioactivity detecting instrument to generate a power spectrum;

(2) setting a basic frequency band, and traversing each frequency point of the basic frequency band aiming at the frequency spectrum data corresponding to the radioactivity detecting instrument;

(3) and for each frequency H with energy in the fundamental frequency band, sequentially judging whether energy exists at a frequency multiplication part 2 and a frequency multiplication part 3 corresponding to the frequency, and if so, judging that the frequency H is the interference frequency of the radionuclide.

2. The method for determining the interference frequency of the radionuclide in the seawater according to claim 1, wherein: in the step (2), the fundamental frequency section is set within the range of 5Hz-20 Hz.

3. The method for determining the interference frequency of the radionuclide in the seawater according to claim 2, wherein: in the step (3), if energy exists at the frequency multiplication part 3 of the frequency H, whether energy exists at the frequency multiplication part 4 of the frequency H is continuously judged, and if the energy exists, the frequency H is judged to be the interference frequency of the radioactive nuclide.

4. The method for determining the interference frequency of the radionuclide in the seawater according to claim 3, wherein: in the step (3), if energy exists at the 4-frequency doubling part of the frequency H, whether energy exists at the 5-frequency doubling part is continuously judged, and if the energy exists, the frequency H is judged to be the interference frequency of the radionuclide.

5. The method for determining the frequency of interference of seawater radionuclides as in any of claims 1-4, wherein: in the step (3), the method for determining whether energy exists at the N-fold frequency position corresponding to the frequency H includes: setting the energy of the frequency H as E; if E_N> E.5%, energy is present at the Ndouble frequency, where N ∈ (2, 3, 4, 5), E_NIs the energy of N H.

Technical Field

The invention belongs to the technical field of seawater detection, and relates to a method for judging interference frequency of a seawater radionuclide.

Background

In the comprehensive measurement process of the ocean radioactive substances, if corresponding radioactive substances exist, corresponding peaks appear in corresponding energy intervals. Because the interference frequency exists in the sea water, although most of the interference frequency is higher, the frequency of the radioactive nuclide is lower, but part of low-frequency signals are mixed into the signal detected by the radioactive nuclide, so that the signal of the radioactive nuclide is changed, the waveform is deformed, even the wave crest drifts, and the detection result of the radioactive nuclide in the sea water is influenced. The judgment method for detecting the interference frequency of the marine radionuclide is necessary for the measurement efficiency of marine detection radionuclide and is the core of the development of the marine radioactivity measurement in China at present. The existing method for monitoring the radioactive environment of seawater is generally based on the premise that the detection signal corresponding to the radioactive substance to be detected in seawater is stable or time-invariant, and is not suitable for complex marine environment.

However, the actual ocean field detection environment is complex and variable, and the interference factors are many. In the actual operation process, the phenomenon that the measurement of marine substances is interfered by the change of marine environment is found, the amplitude of a detected voltage signal can be changed irregularly, and the interference frequency of the marine radionuclide is found in time for obtaining the real detection result of the marine radionuclide. For the above reasons, the existing detection method for detecting radioactive substances in seawater has no accuracy in detection. In the process of detecting the radionuclide, a plurality of peaks, false peaks, superimposed peaks and error peaks caused by interference data can be generated. Therefore, in-situ measurement must find a method to accurately determine the interference frequency corresponding to the radionuclide.

Disclosure of Invention

In order to solve the technical problems, the invention provides a method for judging the interference frequency of the seawater radionuclide, which can identify the interference frequency of the seawater radionuclide and improve the calculation accuracy so as to achieve the purpose of improving the efficiency and accuracy of detecting the radionuclide.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a method for judging interference frequency of seawater radionuclide comprises the following steps:

(1) performing Fourier transform according to the energy signal collected by the radioactivity detecting instrument to generate a power spectrum;

(2) setting a basic frequency band, and traversing each frequency point of the basic frequency band aiming at the frequency spectrum data corresponding to the radioactivity detecting instrument;

(3) and for each frequency H with energy in the fundamental frequency band, sequentially judging whether energy exists at a frequency multiplication part 2 and a frequency multiplication part 3 corresponding to the frequency, and if so, judging that the frequency H is the interference frequency of the radionuclide.

In a preferred embodiment of the present invention, in the step (2), the fundamental frequency range is set in a range of 5Hz to 20 Hz.

Further preferably, in the step (3), if energy exists at a frequency multiplication part 3 of the frequency H, it is continuously determined whether energy exists at a frequency multiplication part 4 of the frequency H, and if so, it is determined that the frequency H is the interference frequency of the radionuclide.

Further preferably, in the step (3), if energy exists at a frequency doubled by 4 of the frequency H, it is continuously determined whether energy exists at a frequency doubled by 5 of the frequency H, and if so, it is determined that the frequency H is the interference frequency of the radionuclide.

Further preferably, in the step (3), the method for determining whether energy exists at the N-fold frequency corresponding to the frequency H includes: setting the energy of the frequency H as E; if E_N> E.5%, energy is present at the Ndouble frequency, where N ∈ (2, 3, 4, 5), E_NIs the energy of N H.

Compared with the prior art, the method for judging the interference frequency of the seawater radionuclide provided by the invention is not limited by accumulation time and marine environment interference, can identify the interference frequency of the seawater radionuclide, and can improve the calculation accuracy.

Drawings

Fig. 1 is a schematic flow chart of a method for determining a seawater radionuclide interference frequency according to an embodiment of the present invention;

fig. 2 is a schematic diagram of frequency doubling detection disclosed in the embodiment of the present invention.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

One of the embodiments provided by the present invention is: a method for determining interference frequency of a marine radionuclide, as shown in fig. 1, comprising the following steps:

s101, performing Fourier transform according to an energy signal collected by a radioactivity detection instrument to generate a power spectrum; the relationship between the channel and the signal value is changed into the relationship between the frequency and the energy. The transformed frequency is related to energy as shown in fig. 2.

S102, setting a fundamental frequency section, wherein the fundamental frequency section is set within the range of 5Hz-20Hz

In this embodiment example, there are 10Hz, 20Hz, 30Hz, 40Hz, 50 Hz; traversing each frequency in the basic frequency band 5Hz-20Hz, 2 are in accordance with the condition: 10Hz and 20 Hz.

S103, searching whether energy exists at the 2 frequency multiplication position corresponding to each frequency H with energy in the basic frequency band or not

The frequency multiplication of 2 of 10Hz is 20Hz, and the energy of 20Hz is more than 5 percent of the energy of 10Hz, so the energy exists in the frequency multiplication of 2 of 10 Hz;

the frequency 2 of 20Hz is 40Hz, and the energy of 40Hz is more than 5% of the energy of 20Hz, so the energy exists in the frequency 2 of 20 Hz.

S104, continuously searching whether energy exists at the frequency multiplication part 3 corresponding to each frequency H with energy in the basic frequency band or not

The frequency multiplication of 3 of 20Hz is 60Hz, and the energy is less than 5 percent of the energy of 20Hz, so the frequency multiplication is not considered and excluded;

the frequency 3 of 10Hz is 30Hz, and the energy of 30Hz is more than 5% of the energy of 10Hz, so the energy exists in the frequency 3 of 10 Hz.

S105, continuously searching whether energy exists at the 4 frequency multiplication position corresponding to each frequency H with energy in the basic frequency band or not

The 4-fold frequency of 10Hz is 40Hz, and the energy of 40Hz is more than 5% of the energy of 10Hz, so the 4-fold frequency of 10Hz has energy.

S106, continuously searching whether energy exists at the 5 frequency multiplication position corresponding to each frequency H with energy in the basic frequency band or not

The 5 times frequency of 10Hz is 50Hz, and the energy of 50Hz is more than 5% of the energy of 10Hz, so the 5 times frequency of 10Hz has energy. The frequency of 10Hz is determined as the interference frequency of the radionuclide.

According to the method for judging the interference frequency of the seawater radionuclide, if the interference frequency exists, energy signals exist at the frequency multiplication part, but if the interference frequency exists at the normal frequency of the radionuclide, the energy signals do not exist at the frequency multiplication part. By adopting the method of the invention, the interference frequency can be basically judged as the energy at the frequency multiplication part of 3. However, in order to improve the accuracy of the determination, whether an energy signal exists at the 4-frequency multiplication part and the 5-frequency multiplication part can be continuously determined. If the energy exists at the frequency multiplication of 5, the frequency can be determined to be the interference frequency, and the judgment is not needed to be continued.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.