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Parametric Narrow-Band InISAR 3D Imaging Based on Compressed Sensing

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Chinese Journal of Electronics 2020年第3期29卷 508-514页

作者： wang baoping ZHANG Yan FANG Yang SONG Zuxun Science and Technology on UAV Laboratory Northwestern Polytechnical University School of Electronic and Information Northwestern Polytechnical University

For muti-scatter point target and undersampled data, tradintional imaging method has a poor precision for imaging result and spin angular *** view of the above problems, this paper proposes a narrow-band Interferometric inverse synthetic aperture radar(InISAR) 3-dimensional(3D) Compressed sensing imaging method based on the joint spin angle velocity error parameter estimation. First, a sparse model of narrow-band spin target is constructed. Then, the image entropy is used as the criterion function to search the optimal angle velocity by the joint reconstruction ***, the image of the target is obtained by interference processing. The simulation results show that compared with the traditional method, the estimation of spin angular velocity and the imaging result are more accurate in proposed method.

关键词： InISAR 3D imaging Narrow-band Spin angular velocity Compressed sensing Joint reconstruction iteration

Near field 3-D imaging approach for joint high-resolution imaging and phase error correction

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Journal of Systems Engineering and Electronics 2017年第2期28卷 199-211页

作者： Yang Fang baoping wang Chao Sun Zuxun Song Shuzhen wang School of Electronics and Information Northwestern Polytechnical University Xi’an 710072 China National Key Laboratory of Science and Technology on UAV Xi’an 710065 China School of Computer Science and Technology Xidian University Xi’an 710071 China

This paper combines compressed sensing (CS) imaging theory and range migration algorithm (RMA), and then proposes a near-field three-dimensional (3-D) imaging approach for joint high-resolution imaging and phase error correction. Firstly, a sparse measurement matrix construction method based on a logistic sequence is proposed, which conducts nonlinear transformation for the determined logistic sequence, making it obey uniform distribution, then conducts sign function mapping, and generates the pseudorandom sequence with Bernoulli distribution, thus leading to good signal recovery under down-sampling and easy availability for engineering realization. Secondly, in combination with the RMA imaging approach, the dictionary with all scene information and phase error correction is constructed for CS signal recovery and error correction. Finally, the non-quadratic solution model jointing imaging and phase error correction based on regularization is built, and it is solved by two steps - the separable surrogate functionals (SSF) iterative shrinkage algorithm is adopted to realize target scattering estimate; the iteration mode is adopted for the correction of the dictionary model, so as to achieve the goal of error correction and highly-focused imaging. The proposed approach proves to be effective through numerical simulation and real measurement in anechoic chamber. The results show that, the proposed approach can realize high-resolution imaging in the case of less data; the designed measurement matrix has better non-coherence and easy availability for engineering realization. The proposed approach can effectively correct the phase error, and achieve highly-focused target image. © 2017 Beijing Institute of Aerospace Information.

关键词： Compressed sensing Error correction Image reconstruction Iterative methods Linear transformations Mathematical transformations Signal reconstruction Signal sampling

A Directional Differential-Fed UWB Antenna with Stable Radiation Pattern

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第6期33卷 -页

作者： Fang Yang wang baoping Sun Chao Song Zuxun wang Shuzhen School of Electronics and Information Northwestern Polytechnical University Science and Technology on UAV Laboratory Northwestern Polytechnical University School of Computer Science and Technology Xidian University

A directional ultra-wideband(UWB)antenna with improved radiation patterns is *** proposed sheme comprises a differential-fed microstrip antenna and a rectangular *** hexagon-shaped slot and four triangle-cut corners on the ground plane of the planar antenna are used to improve the impedance matching within the UWB frequency range.A rectangular cavity is used as the reflector for the planar microstrip antenna,so as to achieve directed *** measured results indicate that the designed antenna exhibits a stable broadside directional radiation patterns within the entire operating frequency ***,thanks to the differentially driven technique,the cross-polarization is greatly decreased and the polarization purity is maintained in a high level.

关键词： differential-fed ultra wide band microstrip antenna

Comment on "Balance recovery control for biped robot based on reaction null space method"

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Control Theory and Technology 2010年第4期8卷 548-548页

作者： baoping wang, Renxi Hu, Jinming Zhang and Chuangfeng Huai Tokyo City University Tokyo Japan

Dear Editor,I am coauthor of the paper entitled "Balance control of a humanoid robot based on the reaction null space method" by Akinori Nishio,Kentaro Takahashi and Dragomir ***,published on pages 1996-2001

关键词： Comment on Balance recovery control for biped robot based on reaction null space method

Adaptive image enhancement algorithm based on fuzzy entropy and human visual characteristics

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Journal of Systems Engineering and Electronics 2018年第5期29卷 1079-1088页

作者： wang baoping MA Jianjun HAN Zhaoxuan ZHANG Yan FANG Yang GE Yimeng National Key Laboratory of Science and Technology on UAV Northwestern Polytechnical University School of Electronics and Information Northwestern Polytechnical University

To overcome the shortcomings of the Lee image enhancement algorithm and its improvement based on the logarithmic image processing(LIP) model, this paper proposes what we believe to be an effective image enhancement algorithm. This algorithm introduces fuzzy entropy, makes full use of neighborhood information, fuzzy information and human visual *** enhance an image, this paper first carries out the reasonable fuzzy-3 partition of its histogram into the dark region, intermediate region and bright region. It then extracts the statistical characteristics of the three regions and adaptively selects the parameter αaccording to the statistical characteristics of the image’s gray-scale values. It also adds a useful nonlinear transform, thus increasing the ubiquity of the algorithm. Finally, the causes for the gray-scale value overcorrection that occurs in the traditional image enhancement algorithms are analyzed and their solutions are *** simulation results show that our image enhancement algorithm can effectively suppress the noise of an image, enhance its contrast and visual effect, sharpen its edge and adjust its dynamic range.

关键词： image enhancement fuzzy entropy fuzzy partition logarithmic image processing(LIP) model human visual characteristic statistical characteristic

Gait planning and intelligent control for a quadruped robot

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控制理论与应用（英文版） 2009年第2期7卷 207-211页

作者： baoping wang Renxi HU Xiaodong ZHANG Chuangfeng HUAI Department of Mechanical and Electronic Engineering Guangdong Baiyun University Guangzhou Guangdong 510450 China Department of Basic Courses Ordnance Engineering College Shijiazhuang Hebei 050003 China School of Mechanical and Electronic Control Engineering Beijing Jiaotong University Beijing 100044 China

We present a method for designing free gaits for a structurally symmetrical quadruped robot capable of performing statically stable, omnidirectional walking on irregular terrain. The robot＇s virtual model is constructed and a control algorithm is proposed by applying virtual components at some strategic locations. The deliberative-based controller can generate flexible sequences of leg transferences while maintaining walking speed, and choose optimum foothold for moving leg based on integration data of exteroceptive terrain profile. Simulation results are presented to show the gait＇s efficiency and system＇s stability in adapting to an uncertain terrain.

关键词： Structural symmetry Quadruped robot Gait planning Intelligent control Virtual model

Balance recovery control for biped robot based on reaction null space method

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控制理论与应用（英文版） 2009年第1期7卷 87-91页

作者： baoping wang Renxi HU Jinming ZHANG Chuangfeng HUAI Department of Mechanical and Electronic Engineering Guangdong Baiyun University Guangzhou Guangdong 510450 China Department of Basic Courses Ordnance Engineering College Shijiazhuang Hebei 050003 China School of Mechanical and Electronic Control Engineering Beijing Jiaotong University Beijing 100044 China

A biped walking robot should be able to keep balance even in the presence of disturbing forces. This paper presents a step strategy concept of biped walking robot that is stabilized by using reaction null space method. The called ＂step strategy＂ can be modeled by means of the reaction null space method that introduced earlier to tackle dynamic interaction problems of free-floating robots, or moving base robots in general. 6-DOF biped robot model simulations are used to confirm the validity.

关键词： Biped robot Balance recovery control Reaction null space Step strategy

Green fluorescent protein (GFP) as a vital marker for studying the interaction of Phytophthora sojae and soybean

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Chinese Science Bulletin 2009年第16期54卷 2822-2829页

作者： CHEN XiaoRen CHENG baoping wang XinLe DONG SuoMeng wang YongLin ZHENG XiaoBo wang YuanChao Department of Plant Pathology Nanjing Agricultural University Nanjing 210095 China

Transgenic Phytophthora sojae strains that produce green fluorescent protein (GFP) were obtained after stable DNA integration using the Hsp70 promoter and the Ham34 terminator of Bremia lactucae. The expression of GFP during different developmental stages of P. sojae was observed using fluorescent microscopy. Based on this reporter system, the histopathologic events caused by the pathogen in soybean leaves, hypocotyls and roots were monitored. Meanwhile, the difference in resistance between different soybean cultivars against P. sojae was analyzed microscopically in roots. The results indicate that GFP can be stably expressed in zoosporangia, zoospores, cysts, hyphae and oospores of P. sojae. Using the GFP marker, the infecting pathogens in leaves, hypocotyls and roots of host could be distinctly visualized. The germ tube length of cysts germinating on the roots of resistant cultivar Nannong 8848 was longer than that on the roots of susceptible cultivar Hefeng 35. These results show for the first time that this eukaryotic reporter can be used in P. sojae as a stable and vital marker, allowing the study of genetics of this hemibiotrophic pathogen.

关键词：绿色荧光蛋白标记大豆疫霉根腐病 GFP 大豆疫霉菌热休克蛋白70 显微镜观察大豆叶片 DNA整合

Influence on lacustrine source rock by hydrothermal fluid： a case study of the Chang 7 oil shale, southern Ordos Basin

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Acta Geochimica 2018年第2期37卷 215-227页

作者： Delu Li Rongxi Li Zengwu Zhu Xiaoli Wu Futian Liu Bangsheng Zhao baoping wang School of Earth Sciences and Resources Chang'an University Xi'an 710054 China Shaanxi Center of Geological Survey Xi'an 710068 China Yanchang Oilfiled Co. Ltd Yan'an 716000 China

Hydrothermal fluid activity during sedimenta- tion of the Triassic Yanchang Formation in the Ordos Basin and the impact of said activity on formation and preservation conditions of source rocks have received little attention. Oil yield, major element, trace element, rare earth element, and total sulfur （TS） data from the oil shale within the Yanchang are here presented and discussed in the context of hydrothermal influence. Oil shale samples returned relatively high total organic carbon （TOC）, in the range of 4.69%-25.48%. A high correlation between TS and TOC suggests TS in the oil shale is dominated by organic sulfur and affected by organic matter. The low Al/ Si ratio of oil shale samples implies quartz is a major mineralogical component. Si/（Si ＋ Al ＋ Fe） values suggest close proximity of the oil shale to a terrigenous source. δEu; Fe versus Mn versus （Cu ＋ Co ＋ Ni）× 10; and SiO2/（K2O ＋ Na2O） versus MnO/TiO2, Fe/Ti, and （Fe ＋ Mn）/Ti are evidence of hydrothermal fluid activity during oil shale sedimentation, and δU and U/Th of the oil shale indicate reducing conditions. The Sr/Ba of oil shale samples suggests fresh-water deposition. The high correlations of Fe/Ti and （Fe ＋ Mn）/Ti with δU, U/Th, and TS demonstrate that hydrothermal fluid activity promotes reducing conditions. Sr/Ba ratios had low correlation with Fe/Ti and （Fe ＋ Mn）/Ti, implying that hydrothermal fluid activity had little impact （Fe ＋ Mn）/Ti, δU, U/Th, and on paleosalinity. Fe/Ti, Cu ＋ Pb ＋ Zn all exhibited high positive correlation coefficients with TOC in oil shale samples, suggesting that more intense hydrothermal fluid activity improves conditions in favor of formation and preservation of organic matter.

关键词： Hydrothermal fluid activity Lacustrine source rock Element geochemistry Chang 7 Ordos Basin