The Experts below are selected from a list of 24363 Experts worldwide ranked by ideXlab platform
Baojun Yang - One of the best experts on this subject based on the ideXlab platform.
-
variable eccentricity hyperbolic trace tfpf for seismic random Noise Attenuation
IEEE Transactions on Geoscience and Remote Sensing, 2014Co-Authors: Yanan Tian, Baojun YangAbstract:Seismic Noise Attenuation to improve signal-to-Noise ratio plays an important role in seismic data processing. In recent years, time-frequency peak filtering (TFPF) has been introduced and applied to seismic random Noise Attenuation successfully. However, in the conventional TFPF, the window length (WL) is fixed and used for all frequency components. As a consequence, serious loss of the effective components is unavoidable due to the inappropriate WL. The recently proposed radial-trace TFPF adapts radial-trace transform to reduce the dominant frequencies of the effective signals. Nevertheless, the radial traces with a fixed inclination angle have some limitations for bent reflection events. To resolve these shortcomings, this paper presents a novel variable-eccentricity hyperbolic-trace TFPF. In this novel method, the noisy record is first resampled along a family of spatial–temporal hyperbolic filtering traces of different bending degrees. In this way, the spatial correlation between the adjacent channels is taken into account, the linearity of the input signals is enhanced, and the estimation bias of the instantaneous frequency is reduced. Moreover, there is little difference between the reduced dominant frequencies. A fixed WL is suitable for all reduced dominant frequencies without distortion of the effective components. Finally, we evaluate the performance of our method on some synthetic records and field data. The experimental results illustrate that our proposed method attenuates random Noise effectively and recovers the effective reflection events smoothly and more continuously compared with the other methods.
-
Noise Attenuation for 2 d seismic data by radial trace time frequency peak filtering
IEEE Geoscience and Remote Sensing Letters, 2011Co-Authors: Ning Wu, Yue Li, Baojun YangAbstract:The time-frequency peak filtering (TFPF) is an effective tool in random-Noise Attenuation and has been applied to seismic record denoising in recent years. The window length (WL) of the time-frequency distribution (TFD) is the key to the conventional TFPF technology. A fixed WL is not optimal for both the low- and high-frequency components at the same time; an adaptive WL results in serious distortion of the reflected waveform. In this letter, we discuss a modified TFPF along the radial-trace direction and prove its advantage in TFD window selection. Experiments on both synthetic models and field data show that the radial-trace TFPF result is no longer much influenced by the WL as the conventional TFPF. Furthermore, it can provide better performance in both random-Noise Attenuation and reflected signal preservation with a fixed WL.
Hanyong Bao - One of the best experts on this subject based on the ideXlab platform.
-
Seismic Random Noise Attenuation Method Based on Variational Mode Decomposition and Correlation Coefficients
Electronics, 2018Co-Authors: Yaping Huang, Hanyong BaoAbstract:Seismic data is easily affected by random Noise during field data acquisition. Therefore, random Noise Attenuation plays an important role in seismic data processing and interpretation. According to decomposition characteristics of seismic signals by using variational mode decomposition (VMD) and the constraint conditions of correlation coefficients, this paper puts forward a method for random Noise Attenuation in seismic data, which is called variational mode decomposition correlation coefficients VMDC. Firstly, the original signals were decomposed into intrinsic mode functions (IMFs) with different characteristics by VMD. Then, the correlation coefficients between each IMF and the original signal were calculated. Next, based on the differences among correlation coefficients of effective signals and random Noise as well as the original signals, the corresponding treatment was carried out, and the effective signals were reconstructed. Finally, the random Noise Attenuation was realized. After adding random Noise to simple sine signals and the synthetic seismic record, the improved complementary ensemble empirical mode decomposition (ICEEMD) and VMDC were used for testing. The testing results indicate that the proposed VMDC has better random Noise Attenuation effects. It was also used in real-world seismic data Noise Attenuation. The results also show that it could effectively improve the signal-to-Noise ratio (SNR) of seismic data and could provide high-quality basic data for further interpretation of seismic data.
Yaping Huang - One of the best experts on this subject based on the ideXlab platform.
-
Seismic Random Noise Attenuation Method Based on Variational Mode Decomposition and Correlation Coefficients
Electronics, 2018Co-Authors: Yaping Huang, Hanyong BaoAbstract:Seismic data is easily affected by random Noise during field data acquisition. Therefore, random Noise Attenuation plays an important role in seismic data processing and interpretation. According to decomposition characteristics of seismic signals by using variational mode decomposition (VMD) and the constraint conditions of correlation coefficients, this paper puts forward a method for random Noise Attenuation in seismic data, which is called variational mode decomposition correlation coefficients VMDC. Firstly, the original signals were decomposed into intrinsic mode functions (IMFs) with different characteristics by VMD. Then, the correlation coefficients between each IMF and the original signal were calculated. Next, based on the differences among correlation coefficients of effective signals and random Noise as well as the original signals, the corresponding treatment was carried out, and the effective signals were reconstructed. Finally, the random Noise Attenuation was realized. After adding random Noise to simple sine signals and the synthetic seismic record, the improved complementary ensemble empirical mode decomposition (ICEEMD) and VMDC were used for testing. The testing results indicate that the proposed VMDC has better random Noise Attenuation effects. It was also used in real-world seismic data Noise Attenuation. The results also show that it could effectively improve the signal-to-Noise ratio (SNR) of seismic data and could provide high-quality basic data for further interpretation of seismic data.
Frank Irving - One of the best experts on this subject based on the ideXlab platform.
-
Measuring the Noise Attenuation of shotblasting helmets.
The Annals of occupational hygiene, 1999Co-Authors: Jacqueline A. Patel, Frank IrvingAbstract:Abstract Air-fed blasting helmets are used in abrasive blasting operations to provide essential face, eye and respiratory protection. BS EN 271: 1995 (equivalent to the European Standard EN 271: 1997), the standard that deals with the construction of blasting helmets, addresses the above matters and also the problem of Noise generated by the breathing air supply. However it has no requirements for manufacturers to measure or report the helmet’s ability to attenuate the very high levels of Noise generated by the blasting process. The aim of the project was to develop a test method to measure the Noise Attenuation of shotblasting helmets. The method developed is an objective measurement, using a head and torso simulator (HATS), which provides a suitable means for helmet manufacturers to report their product’s ability to attenuate blasting Noise. The results from this project showed that the HATS currently prescribed by BS EN 271: 1995 can be used for measuring the Noise Attenuation of helmets against typical shotblasting Noise. Using such a HATS in the proposed test method will give Attenuation values that correlate well with those measured using human subjects. Therefore the HATS already used by manufacturers to show compliance of their product with BS EN 271: 1995 could also be used to provide information on the helmet’s Noise Attenuation. Results from this project also showed that the same HATS can be used, in place of human subjects, to measure the air supply Noise according to the method defined in BS EN 271: 1995. BS EN 271: 1995 is due for revision in 2000. The results from this work should be used to influence future revisions of the standard so that requirements to measure and report Noise Attenuation of shotblasting helmets are considered, a major omission in the present standard.
Jacqueline A. Patel - One of the best experts on this subject based on the ideXlab platform.
-
Measuring the Noise Attenuation of shotblasting helmets
The Journal of the Acoustical Society of America, 2000Co-Authors: Jacqueline A. PatelAbstract:European Standard EN 271: 1995 deals with the construction of air‐fed shotblasting helmets. It specifies minimum requirements for face, eye, and respiratory protection and tests the Noise generated by the breathing air supply. However, it does not test the helmet’s ability to attenuate the very high levels of Noise generated by the shotblasting process. This is a major omission. A test method was developed for measuring the Noise Attenuation provided by shotblasting helmets against typical shotblasting Noise. It involved objective measurements using the head and torso simulator (HATS) currently prescribed by EN 271, fitted with miniature microphones. Using such a HATS was shown to give Attenuation values that correlate well with those measured using human subjects. Results from this project showed: the HATS already used by manufacturers to show compliance of their product with EN 271 can also be used to provide information on the helmet’s Noise Attenuation; and the same HATS can be used, in place of human subjects, to measure the air supply Noise according to the method defined in EN 271. The findings from this work will be used to try to influence future revisions of EN 271 so that the Noise Attenuation of shotblasting helmets is considered.
-
Measuring the Noise Attenuation of shotblasting helmets.
The Annals of occupational hygiene, 1999Co-Authors: Jacqueline A. Patel, Frank IrvingAbstract:Abstract Air-fed blasting helmets are used in abrasive blasting operations to provide essential face, eye and respiratory protection. BS EN 271: 1995 (equivalent to the European Standard EN 271: 1997), the standard that deals with the construction of blasting helmets, addresses the above matters and also the problem of Noise generated by the breathing air supply. However it has no requirements for manufacturers to measure or report the helmet’s ability to attenuate the very high levels of Noise generated by the blasting process. The aim of the project was to develop a test method to measure the Noise Attenuation of shotblasting helmets. The method developed is an objective measurement, using a head and torso simulator (HATS), which provides a suitable means for helmet manufacturers to report their product’s ability to attenuate blasting Noise. The results from this project showed that the HATS currently prescribed by BS EN 271: 1995 can be used for measuring the Noise Attenuation of helmets against typical shotblasting Noise. Using such a HATS in the proposed test method will give Attenuation values that correlate well with those measured using human subjects. Therefore the HATS already used by manufacturers to show compliance of their product with BS EN 271: 1995 could also be used to provide information on the helmet’s Noise Attenuation. Results from this project also showed that the same HATS can be used, in place of human subjects, to measure the air supply Noise according to the method defined in BS EN 271: 1995. BS EN 271: 1995 is due for revision in 2000. The results from this work should be used to influence future revisions of the standard so that requirements to measure and report Noise Attenuation of shotblasting helmets are considered, a major omission in the present standard.