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Science in China(Series F) 2007年第1期50卷 99-104页

作者： MA LinHua CHANG YiLin wang shengda State Key Laboratory of Integrated Service Networks Xidlan University Xi'an 710071 China Aeronauiical Electronics Engineering Department Air Force Engineering University Engineering Institute Xi'an 710038 China

The distribution law of the random code structure of randomly constructed irregular low-density parity-check （LDPC） codes is studied, Based on the Progressive Edge-Growth （PEG） algorithm, a new algorithm which can both ellminate short cycles and keep the distribution of the random code structure is presented, The experimentsl results show that the performance of the irregular LDPC codes constructed by the new algorithm is superior to that of the PEG algorithm,

关键词： Low-density parity.check codes cycles random code structure random distribution characteristics

Improved particle swarm optimization based on particles' explorative capability enhancement

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Journal of Systems Engineering and Electronics 2016年第4期27卷 900-911页

作者： Yongjian Yang Xiaoguang Fan Zhenfu Zhuo shengda wang Jianguo Nan Wenkui Chu Aeronautics and Astronautics Engineering College Air Force Engineering University

Accelerating the convergence speed and avoiding the local optimal solution are two main goals of particle swarm optimization（PSO）. The very basic PSO model and some variants of PSO do not consider the enhancement of the explorative capability of each particle. Thus these methods have a slow convergence speed and may trap into a local optimal solution. To enhance the explorative capability of particles, a scheme called explorative capability enhancement in PSO（ECE-PSO） is proposed by introducing some virtual particles in random directions with random amplitude. The linearly decreasing method related to the maximum iteration and the nonlinearly decreasing method related to the fitness value of the globally best particle are employed to produce virtual particles. The above two methods are thoroughly compared with four representative advanced PSO variants on eight unimodal and multimodal benchmark problems. Experimental results indicate that the convergence speed and solution quality of ECE-PSO outperform the state-of-the-art PSO variants.

关键词： convergence speed particle swarm optimization(PSO) explorative capability enhancement solution quality

Amended Kalman Filter for Maneuvering Target Tracking

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Chinese Journal of Electronics 2016年第6期25卷 1166-1171页

作者： YANG Yongjian FAN Xiaoguang ZHUO Zhenfu wang shengda NAN Jianguo XU Yunshan Aeronautics and Astronautics Engineering College Air Force Engineering University

The conventional Kalman filter(KF) which uses the current measurement to estimate the current state is a posterior estimation. KF is identified as the optimal estimation in linear models with Gaussian noise. However,the performance of KF with incomplete information may be degraded or diverged. In order to improve the performance of KF, an Amended KF(AKF) is proposed by using more posterior measurements. The principle, derivation and recursive process of AKF are presented. The differences among Kalman smoother, adaptive fading method and AKF are analyzed. The simulation results of target tracking with different covariance of motion model indicate the high precision and robustness of AKF.

关键词： Kalman filter(KF) Incomplete information Amended KF(AKF) Maneuvering target tracking

Synthesis of an all-carbon conjugated polymeric segment of carbon nanotubes and its application for lithium-ion batteries

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Nano Research 2023年第7期16卷 10342-10347页

作者： shengda wang Fei Chen Guilin Zhuang Kang Wei Tianyun Chen Xinyu Zhang Chunhua Chen Pingwu Du Hefei National Research Center for Physical Sciences at the Microscale Anhui Laboratory of Advanced Photon Science and TechnologyCAS Key Laboratory of Materials for Energy ConversionDepartment of Materials Science and EngineeringiChEMUniversity of Science and Technology of ChinaHefei 230026China College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310032China

The synthesis and potential applications of nanocarbon materials have attracted much attention in recent ***,we report the design and synthesis of a novel all-carbon conjugated polymeric segment of single-walled carbon nanotubes(poly(cyclo-para-phenylene)(PCPP))and its first application as an anode material for lithium-ion *** as-synthesized PCPP was characterized by Raman spectroscopy,Fourier transform infrared(FTIR),and other *** electrochemical characterization results show the suitability of PCPP as an anode material for lithium-ion *** calculations indicate the unique structural and physical properties of *** realization of PCPP expands the scope of bottom-up synthesis of uniform carbon nanotube segments and their potential applications as new materials for lithium-ion batteries.

关键词： carbon nanomaterials conjugated polymer carbon nanotubes lithium-ion batteries

A new class of generalized quasi-variational inequalities with applications to Oseen problems under nonsmooth boundary conditions

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Science China Mathematics 2024年第2期67卷 315-338页

作者： shengda Zeng Akhtar A.Khan Stanislaw Migórski Guangxi Colleges and Universities Key Laboratory of Complex System Optimization and Big Data Processing Yulin Normal UniversityYulin 537000China Faculty of Mathematics and Computer Science Jagiellonian University in Krak´owKrak´ow 30348Poland Center for Applied and Computational Mathematics School of Mathematical SciencesRochester Institute of TechnologyRochesterNY 14623USA College of Sciences Beibu Gulf UniversityQinzhou 535000China

In this paper, we study a generalized quasi-variational inequality (GQVI for short) with twomultivalued operators and two bifunctions in a Banach space setting. A coupling of the Tychonov fixedpoint principle and the Katutani-Ky Fan theorem for multivalued maps is employed to prove a new existencetheorem for the GQVI. We also study a nonlinear optimal control problem driven by the GQVI and givesufficient conditions ensuring the existence of an optimal control. Finally, we illustrate the applicability of thetheoretical results in the study of a complicated Oseen problem for non-Newtonian fluids with a nonmonotone andmultivalued slip boundary condition (i.e., a generalized friction constitutive law), a generalized leak boundarycondition, a unilateral contact condition of Signorini’s type and an implicit obstacle effect, in which themultivalued slip boundary condition is described by the generalized Clarke subgradient, and the leak boundarycondition is formulated by the convex subdifferential operator for a convex superpotential.

关键词： generalized quasi-variational inequality existence theorem optimal control Kakutani-Ky Fan theorem Oseen problem non-Newtonian fluid nonmonotone slip boundary condition

Highly strengthening and toughening biomimetic ceramic structures fabricated via a novel coaxially printing

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Journal of Advanced Ceramics 2024年第4期13卷 403-412页

作者： Kunkun Song shengda Yang Ningqi Shao Yantang Zhao Peng He Yongfeng Wei Hengzhong Fan Yongsheng Zhang Qiangqiang Zhang State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China School of Civil Engineering and Mechanics Lanzhou UniversityLanzhou 730000China Key Laboratory of Mechanics on Disaster and Environment in Western China(Lanzhou University) Ministry of EducationLanzhou 730000.China

Additive manufacturing technology,by manipulating and emulating inherent multiscale,multi-material,and multifunctional structures found in nature,has created new opportunities for constructing heterogeneous structures associated with special properties and achieving ultra-high mechanical performance and reliability in ceramic composite *** this study,we have developed an innovative fabrication method designated as coaxial 3D printing for the synchronous construction of two constituents into ceramic composites with a tooth enamel biomimetic ***,the stiff silicate and flexible epoxy served as a strengthening bridge and toughening layer,*** method differed from the traditional approach of randomly dispersing reinforcing components within a ceramic *** allowed for the direct creation of an internally effective three-dimensional reinforcement network structure in ceramic *** process facilitated synergistic deformation and simultaneous enhancement of multiple materials and hierarchical *** to the uniform distribution of internal stress and effective block of microcrack propagation,the biomimetically structured silicate/epoxy ceramic composite has demonstrated much significant enhancement in mechanical properties,includingcompressive strength(48.8±3.12MPa),flexuralstrength(10.39±1.23MPa),andflexuraltoughness(218.7±54.6kJ/m^(3)),which was 0.5,2.1,and 47.5 times as high as those of the intrinsic brittle silicate ceramics,***-situ characterization and multiscale finite element simulation of microstructural evolution during three-point bending deformation further validated multiple-step features of the fracture process(silicate bridge fracture,interface detachment,epoxy extraction,and rupture),which benefited from interpenetrating structural features achieved by coaxial printing to accomplish with the complex propagating routines of the crack deflection in silicate ceramic *** coaxia

关键词： coaxial 3D printing silicate ceramic composites enamel biomimetic microstructure strengthening bridge tougheninglayer crackdeflection

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共形阵低副瓣方向图综合性能分析

电波科学学报 2013年第6期28卷 1116-1121页

作者：杨永建樊晓光王晟达马健空军工程大学航空航天工程学院陕西西安710038

针对粒子群优化算法在方向图综合中如何评价其性能的问题,通过定义有效性和稳定性两个性能指标,从统计角度对粒子群算法在共形阵低副瓣方向图综合中的性能进行了评价.仿真结果表明所定义的性能指标可以有效评价算法综合方向图的性能,具... 详细信息

针对粒子群优化算法在方向图综合中如何评价其性能的问题,通过定义有效性和稳定性两个性能指标,从统计角度对粒子群算法在共形阵低副瓣方向图综合中的性能进行了评价.仿真结果表明所定义的性能指标可以有效评价算法综合方向图的性能,具有较强的实际应用指导意义.

关键词：共形阵列天线方向图综合二分粒子群优化性能指标

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相控阵雷达波控系统研究

微计算机信息 2008年第10期24卷 81-83页

作者：高云珠王晟达空军工程大学工程学院陕西西安710038

基于相控阵天线波束控制的基本原理和波控系统的任务,讨论了相控阵雷达波控系统的相关问题。通过MATLAB仿真可知,依据相控阵天线雷达的方向图的可分离性,实现了对雷达波束的控制,本文采用分布式查表和程序运算相结合的方法,提高了波控... 详细信息

基于相控阵天线波束控制的基本原理和波控系统的任务,讨论了相控阵雷达波控系统的相关问题。通过MATLAB仿真可知,依据相控阵天线雷达的方向图的可分离性,实现了对雷达波束的控制,本文采用分布式查表和程序运算相结合的方法,提高了波控运算速度。

关键词：相控阵天线波束控制仿真

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荧光碳点的合成、性质和应用

影像科学与光化学 2016年第3期34卷 203-218页

作者：王胜达袁楠朱志峰蒋阳合肥工业大学材料科学与工程学院安徽合肥230009

与传统半导体发光材料相比,荧光碳点作为一种新型的碳纳米发光材料,因其优异的生物相容性、良好的发光性能、简单的合成工艺、低廉的成本等优点而备受关注。荧光碳点在生物荧光标定、医学传感器、光诊疗剂以及发光器件等方面具有广阔的... 详细信息

与传统半导体发光材料相比,荧光碳点作为一种新型的碳纳米发光材料,因其优异的生物相容性、良好的发光性能、简单的合成工艺、低廉的成本等优点而备受关注。荧光碳点在生物荧光标定、医学传感器、光诊疗剂以及发光器件等方面具有广阔的应用潜力。本文重点阐述了荧光碳点的合成方法、显微结构分析、荧光机理及应用的最新成果,希望为荧光碳点合成与应用研究的发展提供参考。

关键词：碳点荧光生物成像光诊疗剂发光器件

砂卵石地层盾构区间地表沉降影响因素聚类分析

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吉林大学学报（地球科学版） 2024年第1期54卷 219-230页

作者：王伟王兴周勋韦生达长春工程学院土木工程学院长春130012 中交路桥北方工程有限公司北京100024

为了掌握盾构掘进参数和地质条件对砂卵石地层盾构区间地表沉降的综合影响规律,依托成都地铁某盾构区间,结合团队前期地表沉降与掘进参数的关系,确定了总推力、刀盘转速、螺旋机转速、上覆土层厚度、地下水位、卵石层厚度6种聚类指标,利... 详细信息

为了掌握盾构掘进参数和地质条件对砂卵石地层盾构区间地表沉降的综合影响规律,依托成都地铁某盾构区间,结合团队前期地表沉降与掘进参数的关系,确定了总推力、刀盘转速、螺旋机转速、上覆土层厚度、地下水位、卵石层厚度6种聚类指标,利用K均值聚类算法对各参数指标的实际监测数据进行聚类,综合分析各个指标对地表沉降的影响。结果表明:1)根据K均值聚类结果把监测点即施工地段划分为3种地表沉降风险等级,监测点1—3为危险(Ⅰ级),监测点7—13、16—19、25—34为较危险(Ⅱ级),监测点4—6、14—15、20—24为安全(Ⅲ级)。2)根据聚类结果可知,在特定范围内掘进参数、地层构造与地表沉降之间具有正、负相关性关系。3)通过分析地层构造、掘进参数与地表沉降的关系,得出当上覆土层厚度较大、地下水位较小、卵石层厚度较大时,掘进参数控制范围为总推力29034.00~31181.95 kN,刀盘转速1.25~1.32 r/min,螺旋机转速6.13~6.98 r/min;当上覆土层厚度较小、地下水位较小、卵石层厚度较小时,掘进参数控制范围为总推力34419.89~36867.28 kN,刀盘转速1.44~1.45 r/min,螺旋机转速5.74~6.99 r/min。

关键词：砂卵石地层盾构地表沉降聚类分析