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带感性负载的Buck-Boost变换器的非线性行为分析及优化控制

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电测与仪表 2024年第4期61卷 184-191页

作者：龚仁喜彭维玉王保平黎洛琦王奇广西大学电气工程学院南宁530004

Buck-Boost变换器在某些参数发生变化时会呈现出丰富的非线性行为,这些行为将严重影响系统的稳定性,使得系统输出的电能质量劣化。文章基于实际变换器的负载特性,深入研究了感性阻抗负载下Buck-Boost变换器的非线性行为产生机理,提出了... 详细信息

Buck-Boost变换器在某些参数发生变化时会呈现出丰富的非线性行为,这些行为将严重影响系统的稳定性,使得系统输出的电能质量劣化。文章基于实际变换器的负载特性,深入研究了感性阻抗负载下Buck-Boost变换器的非线性行为产生机理,提出了一种对数延迟反馈控制方法。该方法选取系统的输出延迟值与自身的值作差形成反馈信号;将该信号通过比例环节、求和环节和对数环节形成控制信号,以负反馈的形式施加于系统;最后基于稳定判据确定最优控制参数并对系统实施控制。为验证该方法的有效性,进行了大量的仿真实验,结果表明该方法能很好地抑制系统的非线性行为,扩展其稳定边界,改善系统输出的电能质量。

关键词： Buck-Boost变换器非线性行为感性阻抗负载对数延迟反馈

Image segmentation algorithm based on high-dimension fuzzy character and restrained clustering network

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Journal of Systems Engineering and Electronics 2014年第2期25卷 298-306页

作者： baoping wang Yang Fang Chao Sun Science and Technology on UAV Laboratory Northwestern Polytechnical University

An image segmentation algorithm of the restrained fuzzy Kohonen clustering network （RFKCN） based on high- dimension fuzzy character is proposed. The algorithm includes two steps. The first step is the fuzzification of pixels in which two redundant images are built by fuzzy mean value and fuzzy median value. The second step is to construct a three-dimensional （3-D） feature vector of redundant images and their original images and cluster the feature vector through RFKCN, to realize image seg- mentation. The proposed algorithm fully takes into account not only gray distribution information of pixels, but also relevant information and fuzzy information among neighboring pixels in constructing 3- D character space. Based on the combination of competitiveness, redundancy and complementary of the information, the proposed algorithm improves the accuracy of clustering. Theoretical anal- yses and experimental results demonstrate that the proposed algorithm has a good segmentation performance.

关键词： image segmentation high-dimension fuzzy character,restrained fuzzy Kohonen clustering network (RFKCN).

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

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

个体化营养指导应用在妊娠期糖尿病孕妇胰岛素治疗期间的效果及对妊娠结局的影响

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中国药物滥用防治杂志 2024年第9期30卷 1636-1638,1650页

作者：王保萍柳红芳丁君四安徽省池州市东至县妇幼保健计划生育服务中心安徽池州247200

目的:探讨个体化营养指导应用在妊娠期糖尿病孕妇胰岛素治疗期间的效果及对妊娠结局的影响。方法:选择我院2022年4月—2023年4月间收治的80例GDM患者,采用随机数字表法分为观察组和对照组,各40例。所有患者经口服二甲双胍缓释片、皮下... 详细信息

目的:探讨个体化营养指导应用在妊娠期糖尿病孕妇胰岛素治疗期间的效果及对妊娠结局的影响。方法:选择我院2022年4月—2023年4月间收治的80例GDM患者,采用随机数字表法分为观察组和对照组,各40例。所有患者经口服二甲双胍缓释片、皮下注射门冬胰岛素治疗,对照组开展常规饮食指导,观察组开展个体化营养指导,比较两组治疗前后空腹血糖(FPG)、餐后2 h血糖(2 hPG)、糖化血红蛋白(Hb A1c)、Cys C、Hcy指标变化及不良妊娠结局。结果:治疗后,观察组FPG、2 hPG、Hb A1c、Cys C、Hcy指标均低于对照组,差异有统计学意义(P<0.05);观察组不良妊娠结局总发生率为5.00%,低于对照组的20.00%,差异有统计学意义(P<0.05)。结论:在二甲双胍、门冬胰岛素用药基础上,开展个体化营养指导可降低妊娠期糖尿病孕妇血清Cys C、Hcy水平,对血糖的控制效果好,并能在一定程度上降低不良妊娠结局风险,值得临床应用。

关键词：妊娠期糖尿病个体化营养指导门冬胰岛素血糖控制妊娠结局

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

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数据资产的十大学理解读

财务管理研究 2024年第7期 71-80页

作者：孙娜倪健邓欣茹王保平北京国家会计学院北京101312 中建八局浙江公司杭州310000 浙江国资国企研究院有限公司杭州310000

在数字技术强力推动的数据经济时代,各种数据的创新应用日新月异、层出不穷。数据资产已经成为政府管理、企业运营和社会关注的重大热点问题,法律确权、质量合规、财务确认等一系列问题经常引起关注和争议。相应的多视角理论辨析无疑值... 详细信息

在数字技术强力推动的数据经济时代,各种数据的创新应用日新月异、层出不穷。数据资产已经成为政府管理、企业运营和社会关注的重大热点问题,法律确权、质量合规、财务确认等一系列问题经常引起关注和争议。相应的多视角理论辨析无疑值得学术界系统地进行分析和研究。只有得到理论探索的匹配与支撑,构建系统性体系,数据资产这一新生事物才能得到持续而健康的发展壮大。尝试多维度探索数据资产的相关理论认知,起步于数据技术分析,关注其经济理论,并着眼于政治学、社会学、法规学、会计学,同时从监管学、统计学、价值评估角度进行分析,最后框架性地提出税政设计的理念。实践探索与理论研究融合共进,是实现数据资产管理事业健康发展的必由之路。因此,需要主管部门、学界及相关产业着眼于多个维度,更加深入地研究数据资产的实现路径。

关键词：数据资产学理探讨资产管理