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Petroleum Science 2019年第5期16卷 1015-1027页

作者： Lei Wang Shao-Gui Deng Pan Zhang Ying-Chang Cao Yi-Ren Fan Xi-Yong Yuan School of Geosciences China University of PetroleumQingdao 266580ShandongChina Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071ShandongChina CNPC Key Laboratory for Well Logging China University of PetroleumQingdao 266580ShandongChina

We present systematic investigations on the physics,detection performance and inversion of logging-while-drilling extradeep azimuthal resistivity measurements(EDARM).First,the definitions of EDRAM measurements are discussed,followed by the derivation of the attenuation and phase-shift geometrical factors to illustrate the relative contributions of formation units to the observed ***,a new definition of detection depth,which considers the uncertainty of inversion results caused by the data noise,is proposed to quantify the detection capability of ED ***,the B ayesian theory associated with Markov chain Monte Carlo sampling is introduced for fast processing of EDARM *** results show that ED ARM is capable of detecting the azimuth and distance of remote bed boundaries,and the detection capability increases with increasing spacing and resistivity *** EDARM tool can accommodate a large range of formation resistivity and is able to provide the resistivity anisotropy at arbitrary relative dipping *** addition,multiple bed boundaries and reservoir images near the borehole are readily obtained by using the Bayesian inversion.

关键词： Extra-deep azimuthal resistivity measurements(EDARM) detection performance Inversion method Reservoir imaging detection of multiple bed boundaries

Cued search algorithm with uncertain detection performance for phased array radars

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Journal of Systems Engineering and Electronics 2013年第6期24卷 938-945页

作者： Jianbin Lu Hui Xiao Zemin Xi Mingmin Zhang Electronic Engineering College Naval University of Engineering Air Force Early Warning Academy

A cued search algorithm with uncertain detection performance is proposed for phased array radars. Firstly, a target search model based on the information gain criterion is presented with known detection performance, and the statistical characteristic of the detection probability is calculated by using the fluctuant model of the target radar cross section （RCS）. Secondly, when the detection probability is completely unknown, its probability density function is modeled with a beta distribution, and its posterior probability distribution with the radar observation is derived based on the Bayesian theory. Finally simulation results show that the cued search algorithm with a known RCS fluctuant model can achieve the best performance, and the algorithm with the detection probability modeled as a beta distribution is better than that with a random selected detection probability because the model parameters can be updated by the radar observation to approach to the real value of the detection probability.

关键词： phased array radar detection performance cued search information gain beta distribution

On detection performance of MIMO radar for Rician target

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Science in China(Series F) 2009年第8期52卷 1456-1465页

作者： TANG Jun WU Yong PENG YingNing WANG XiuTan Department of Electronic Engineering Tsinghua University Beijing 100084 China

By using spatial diversity, multiple-input-multiple-output （MIMO） radar can improve detection performance for fluctuating targets. In this paper, we propose a spatial fluctuation target model for MIMO radar, where targets are classified as non-fluctuating target, Rayleigh target and Rician target. Based on Stein＇s lemma, we use relative entropy to study detection performance of optimum detector for Rician target. It is found that in low signal noise ratio （SNR） region, the performance improvement of MIMO radar for detecting Rician target depends on array gain, which is related to the number of receivers. In high SNR region, the improvement of performance depends on diversity gain, which is related to the product of the number of receivers and the number of transmitters. The conclusions of this paper are important for designing MIMO radar system.

关键词： MIMO radar relative entropy Rician target detection performance

Determination of the principal components for the optimal detection performance of a combined index

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Determination of the principal components for the optimal de...

The Visible Light Imaging detection performance of Spaced-target

第25届中国控制与决策会议

作者： Tian Qiu Xiaojing Bai Xiyu Zheng Xiang Zhu State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of Control and Computer Engineering North China Electric Power University

ISBN: (纸本)9781467355339

In process monitoring, faults might be completely detected by or or both of them. However, one index rather than two indices is preferred to monitor a process in practice. The number of principal components （PCs） in principal component analysis （PCA） impacts the fault detection performance obviously. In this paper, we focus on developing a selection criterion for the number of the PCs based on the best detection performance of the combined index and discussing the uncertainty of PCA model through cross validation. The simulation demonstrates that one index has a good detection performance and simplifies the detection system.

关键词： principal component analysis (PCA) fault detection detection performance fault amplitude

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The Visible Light Imaging Detection Performance of Spaced-ta...

A high performance waveform and a new ranging method for the proximity detector

2015光电防御技术学术研讨会

作者： HOU Zhao-fei ZHAO Wei YU Feng Key Laboratory of Electro-Optical Countermeasures Test & Evaluation Technology

According to the radiation intensity of the spaced-target, the SNR and detection distance of the spaced target of visible light has been study and analyzed. The relationship between SNR, detection distance and the size of the spaced-target, the reflectance, observed phase angle, as well as the entrance pupil area has been obtained. The specific formula of the detection distance of the spaced-target of detection of the visible light detection system is given. And key indicators that impact the detection distance of spaced target of visible light have been analyzed. The study provides a theoretical basis for the performance of the future space-target detection system.

关键词： Spaced-target Visible light detection performance detection distance SNR

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Defence Technology（防务技术） 2020年第4期16卷 834-845页

作者： Qi-le Chen Xin-hong Hao Xiao-peng Yan Ping Li School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

Signal modulation is an essential design factor for proximity detectors and directly affects the system's potential *** order to achieve the advantages of chaotic codes bi-phase modulation(CCBPM)and linear frequency modulation(LFM) simultaneously,this paper designed a waveform which combined chaotic codes bi-phase modulation and linear frequency modulation(CCBPM-LFM) for proximity *** CCBPM-LFM waveform was analyzed in the aspect of time delay resolution(TDR) and Doppler tolerance(DT) based on ambiguity function(AF).Then,a ranging method,which we called instant correlation harmonic demodulation(ICHD),was presented for the detector using the CCBPM-LFM *** combining time domain instant correlation with harmonic demodulation,the ICHD solved the problem caused by combination modulation and made the most of the linear frequency modulation(LFM) harmonics and the correlation of chaotic ***,a prototype was implemented and ranging experiments were carried *** the theoretical analysis and experimental results,the proximity detector used the CCBPM-LFM waveform has an outstanding detection performance.

关键词： Proximity detectors detection performance Combination modulation Chaotic codes bi-phase modulation Linear frequency modulation

A General Linguistic Steganalysis Framework Using Multi-Task Learning

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Computer Systems Science & Engineering 2023年第8期46卷 2383-2399页

作者： Lingyun Xiang Rong Wang Yuhang Liu Yangfan Liu Lina Tan School of Computer and Communication Engineering Changsha University of Science and TechnologyChangsha410114China School of Computer Science and Electronic Engineering University of EssexColchesterCO43SQUK School of Computer Science Hunan University of Technology and BusinessChangsha410205China

Prevailing linguistic steganalysis approaches focus on learning sensitive features to distinguish a particular category of steganographic texts from non-steganographic texts,by performing binary *** it remains an unsolved problem and poses a significant threat to the security of cyberspace when various categories of non-steganographic or steganographic texts *** this paper,we propose a general linguistic steganalysis framework named LS-MTL,which introduces the idea of multi-task learning to deal with the classification of various categories of steganographic and non-steganographic ***-MTL captures sensitive linguistic features from multiple related linguistic steganalysis tasks and can concurrently handle diverse tasks with a constructed *** the proposed framework,convolutional neural networks(CNNs)are utilized as private base models to extract sensitive features for each steganalysis ***,a shared CNN is built to capture potential interaction information and share linguistic features among all ***,LS-MTL incorporates the private and shared sensitive features to identify the detected text as steganographic or *** results demonstrate that the proposed framework LS-MTL outperforms the baseline in the multi-category linguistic steganalysis task,while average Acc,Pre,and Rec are increased by 0.5%,1.4%,and 0.4%,*** ablation experimental results show that LS-MTL with the shared module has robust generalization capability and achieves good detection performance even in the case of spare data.

关键词： Linguistic steganalysis multi-task learning convolutional neural network(CNN) feature extraction detection performance

Application of modified multiple subarrays detection method to multibeam bathymetry system

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Journal of Marine Science and Application 2005年第2期4卷 39-43页

作者： ZHOU Tian LI Hai-sen ZHU Zhi-de YUAN Yan-yi School of Underwater Acoustic Engineering Harbin Engineering University Harbin 150001 China Post-Doctor Workstation of Instrument Science and Technology Harbin Institute of Technology Harbin 150001 China

Either amplitude based methods or phase based methods are usually used in multibeam bathymetry system and chosen in practical measurement by ad hoc criteria. The errors of the detection are often caused by choosing wrong detection method. In this paper a modified multiple subarrays amplitude-phase united detection method is proposed , which uses both the amplitude and phase of echo from *** new method not only realizes the super-wide swath coverage, but also improves the detection performance by using the phase differences among subarrays in place of phases of subarrays to estimate the phase slope image. Experimental results are also analyzed and discussed to demonstrate the effectivity of the proposed approach.

关键词： multibeam bathymetry multiple subarrays phase slope image detection performance

performance Analysis of Techniques Used for Determining Land Mines

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International Journal of Geosciences 2014年第10期5卷 1163-1189页

作者： Yavuz Ege Adnan Kakilli Osman Kilic Hüseyin Calik Hakan Citak Sedat Nazlibilek Osman Kalender Department of Physics Necatibey Faculty of EducationBalikesir UniversityBalikesirTurkey Electrical Education Department Technical Education FacultyMarmara UniversityIstanbulTurkey Technical Sciences Vocational High School Istanbul UniversityIstanbulTurkey Balikesir Vocational High School Balikesir UniversityBalikesirTurkey Department of Mechatronics Engineering Faculty of EngineeringAtilim UniversityAnkaraTurkey Department of Electrical-Electronics Engineering Faculty of EngineeringOrhangazi UniversityBursaTurkey

Today, remote sensing is used for different methods and different purposes. In all of the detection methods, some considerations such as low energy consumption, low cost, insensitivity to environmental changes, high accuracy, high reliability and robustness become important. Taking into account these facts, remote sensing methods are used in applications such as geological and archeological research, engineering areas, health services, preserving and controlling natural life, determination of underground sources, controlling air, sea and road traffic, military applications, etc. The method to be used is based on the object type to be detected, material to be made, and location to be found. The remote sensing methods from the past up to today can be listed as acoustic and seismic, ground penetration radar (GPR) detection, electromagnetic induction, infrared (IR) imaging, neutron quadrupole resonance (NQR), thermal neutron activation (TNA), neutron back scattering, X-ray back scattering, and magnetic anomaly detection. In these methods, detected raw images have to be processed, filtered and enhanced. In order to achieve these operations, some algorithms are needed to be developed. In this study, the methods used in detecting land mines remotely and their performance analysis have been given. In this way, the last situation on the advantages and disadvantages of methods used, application areas and detection accuracies are determined. Furthermore, the algorithms such as transmission line matrix (TLM), finite difference time-domain (FDTD), the method of moment (MoM), split step parabolic equation (SSPE) and image processing and intelligent algorithms are presented in detail.

关键词： Remote Sensing Land Mine detection performance Algorithm

Robust adaptive matched field processing with environmental uncertainty

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Chinese Journal of Acoustics 2006年第2期25卷 159-170页

作者： YANG Kunde MA Yuanliang ZHANG Zhongbing ZOU Shixin Institute of Acoustic Engineering Northwestern Polytechnical University Xi'an 710072

The main challenges on detection and localization of quiet targets in littoral regions for passive sonar are the complicated acoustic propagation and the prevalence of loud ship interferences on the surface. Adaptive matched field processing can provide the ability to null surface interferences, but the mismatch between the computed and actual array steering vectors due to environment uncertainty, and the motion of both targets and interferences can result in loss of array gain significantly. To address the problem of environmental mismatch and target motion, a robust motion compensation algorithm and a system scheme for adaptive matched field processing have been developed. Both Numerical simulation and analysis of experimental data demonstrates that the robust AMFP scheme could suppress surface loud interferences and improve the detection performance for underwater weak moving targets in complex shallow water.

关键词： matched field processing simulation and analysis detection performance acoustic propagation motion compensation experimental data moving targets shallow water