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A CONSTRAINED OPTIMIZATION APPROACH FOR LCP

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Journal of Computational Mathematics 2004年第4期22卷 509-522页

作者： ju-liangzhang jianchen Xin-jianZhuo DepartmentofManagementScienceandEngineering SchoolofEconomicsandManagementTsinghuaUniversityBeijing100084China SchoolofInformationEngineering BeijingUniversityofpostsandTelecommunicationBeijing100876China

In this paper, LCP is converted to an equivalent nonsmooth nonlinear equation system H(x,y) = 0 by using the famous NCP function-Fischer-Burmeister function. Note that some equations in H(x, y) = 0 are nonsmooth and nonlinear hence difficult to solve while the others are linear hence easy to solve. Then we further convert the nonlinear equation system H(x, y) = 0 to an optimization problem with linear equality constraints. After that we study the conditions under which the K-T points of the optimization problem are the solutions of the original LCP and propose a method to solve the optimization problem. In this algorithm, the search direction is obtained by solving a strict convex programming at each iterative point, However, our algorithm is essentially different from traditional SQP method. The global convergence of the method is proved under mild conditions. In addition, we can prove that the algorithm is convergent superlinearly under the conditions: M is P0 matrix and the limit point is a strict complementarity solution of LCP. Preliminary numerical experiments are reported with this method.

关键词： LCP Strict complementarity Nonsmooth equation system PQ matrix Super-linear convergence

Nanograting‑Based Dynamic Structural Colors Using Heterogeneous Materials

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Nano-Micro Letters 2025年第3期17卷 138-151页

作者： Jingang Wang Haibo Yu jianchen Zheng Yuzhao Zhang Hongji Guo Ye Qiu Xiaoduo Wang Yongliang Yang Lianqing Liu State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Dynamic structuralcolors can change in response todifferent environmental *** ability remains effectiveeven when the size of the speciesresponsible for the structural coloris reduced to a few micrometers,providing a promising sensingmechanism for solving microenvironmentalsensing problems inmicro-robotics and ***, the lack of dynamicstructural colors that can encoderapidly, easily integrate, and accuratelyreflect changes in physical quantities hinders their use in microscale sensing applications. Herein, we present a 2.5-dimensionaldynamic structural color based on nanogratings of heterogeneous materials, which were obtained by interweaving a pH-responsive hydrogelwith an IP-L photoresist. Transverse gratings printed with pH-responsive hydrogels elongated the period of longitudinal grating in the swollenstate, resulting in pH-tuned structural colors at a 45° incidence. Moreover, the patterned encoding and array printing of dynamic structuralcolors were achieved using grayscale stripe images to accurately encode the periods and heights of the nanogrid structures. Overall, dynamicstructural color networks exhibit promising potential for applications in information encryption and in situ sensing for microfluidic chips.

关键词： Dynamic structural colors Four-dimensional printing pH-responsive Nanogrid Heterogeneous materials

Fluorescence microscope light source based on integrated LED

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Light(Science & Applications) 2023年第10期12卷 1990-1991页

作者： jianchen Zi Hai Bi Jihua Laboratory No.28 Huandao South RoadNanhai district528200FoshanChina

An LED-integrated excitation cube(LEC)was designed to address the limitations of conventional fluorescence *** LEC has a decentralized structure,high optical power density,and efficient *** optical efficiency of LECs is 1–2 orders of magnitude higher than that of mercury lamps,enabling high-quality fluorescence imaging with spectral coverage from UV to *** can be easily installed on commercial fluorescence microscopes by replacing conventional fluorescence filter cubes,and a built-in LEC driver can identify the types of LEDs in different spectral bands to adopt optimal operating conditions.

关键词： Fluorescence illumination mercury

Entropy,Periodicity,and Graphs with Zero Euler Characteristic

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Acta Mathematica Sinica,English Series 2004年第3期20卷 415-422页

作者： JieLU JinChengXIONG jianchen DepartmentofMathematics SouthChinaNormalUniversityGuangzhou510631P.R.China DepartmentofMathematics JilinNormalUniversitySiping136000P.R.China

Let G be a graph which contains exactly one simple closed *** prove that a continuous map f:G→G has zero topological entropy if and only if there exist at most k■[(Edg(G)+End(G)+ 3)/2]different odd numbers n_1,...,n_k such that Per(f)is contained in ∪_i^k=1 ∪_j~∞=0 n_i2~j,where Edg(G) is the number of edges of G and End(G)is the number of end points of G.

关键词： Graph Topological entropy Inverse limit Period

Thermally Induced Vibration Analysis of Flexible Beams Based on Isogeometric Analysis

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Computer Modeling in Engineering & Sciences 2021年第9期128卷 1007-1031页

作者： jianchen Wu Yujie Guo Fangli Wang College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016China School of Mechanical Engineering Jinling Institute of TechnologyNanjing211169China

Spacecraft flexible appendages may experience thermally induced vibrations(TIV)under sudden heating loads,which in consequence will be unable to complete their intended *** analysis(IGA)utilizes,in an isoparametric concept,the same high order and high continuity non-uniform rational B-splines(NURBS)to represent both the geometry and the physical field of the *** to the traditional Lagrange polynomial based finite element method where only C0-continuity across elements can be achieved,IGA is geometrically exact and naturally fulfills the C1-continuity requirement of Euler–Bernoulli(EB)beam elements,therefore,does not need extra rotational *** this paper,we present a thermally induced vibration analysis framework based on the isogeometric method where thermal and structural behaviors are *** fully exploited the higher order,higher continuous and geometric exactness of the NURBS basis with both benchmarks and sophisticated *** particular,we studied the thermally induced vibrations of the Hubble Space Telescope(HST)solar panel where main factors influencing thermal flutters are studied,and where possible improvements of the analytical reference methods are ***,thermally induced vibrations of the thin-walled lenticular tubes are studied and two new configurations of the tube are proposed to effectively suppress the thermally induced *** examples of both benchmarks and sophisticated problems confirm the accuracy and efficiency of the isogeometric analysis framework for thermally induced vibration analysis of space structures.

关键词： Thermally induced vibration thermal flutter radiation heat transfer isogeometric analysis thermal structural coupling

紫外荧光法测定航天煤油硫含量的影响因素研究

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石油炼制与化工 2025年第1期56卷 181-186页

作者：周建臣俞少行唐毅吴奖君西昌卫星发射中心海南文昌571300 航天发射场可靠性技术重点实验室

系统地研究了紫外荧光法各参数对航天煤油硫含量测试结果的影响,分析了硫信号积分值随进样速率、进样量、负高压、裂解氧流量、氩气流量、进口氧流量和裂解温度的变化规律,得到了最佳测试条件。结果表明:进样速率、裂解氧流量、氩气流... 详细信息

系统地研究了紫外荧光法各参数对航天煤油硫含量测试结果的影响,分析了硫信号积分值随进样速率、进样量、负高压、裂解氧流量、氩气流量、进口氧流量和裂解温度的变化规律,得到了最佳测试条件。结果表明:进样速率、裂解氧流量、氩气流量、负高压是紫外荧光法精确测定硫含量的主要影响因素;最佳进样速率和最佳氩气流量会受航天煤油热裂解反应的影响,最佳裂解氧流量与进样速率有关,负高压范围由基线噪声情况确定,最佳进样量可根据负高压对最小进样量的影响来确定。本研究为紫外荧光法准确、高效地测定航天煤油硫含量提供了测试参数参考,也给探究最佳测试条件提供了试验方法。

关键词：航天煤油硫含量紫外荧光法热裂解

An improved probabilistic relaxation method for matching multi-scale road networks

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International Journal of Digital Earth 2018年第6期11卷 635-655页

作者： jianchen Zhang Yanhui Wang Wenji Zhao College of Resources Environment and Tourism Capital Normal UniversityBeijingPeople’s Republic of China D Information Collection and Application Key Lab of Education Ministry Capital Normal UniversityBeijingPeople’s Republic of China Beijing State key Laboratory Incubation Base of Urban Environmental Processes and Digital Simulation Capital Normal UniversityBeijingPeople’s Republic of China

Matching multi-scale road networks in the same area is the first step in merging two road networks or updating one based upon the *** quality of the merge or update depends greatly on the matching accuracy of the two road *** propose an improved probabilistic relaxation method,considering both local and global optimizations for matching multi-scale of road *** aim is to achieve local optimization,as well as to address the identification of the M:N matching pattern by means of inserting virtual nodes to achieve global optimization ***,by adding two attribute-related evaluation indicators,we developed four evaluation indicators to evaluate the matching accuracy,considering both geographic and attribute *** paper also provides instructions on how to identify the proper buffer threshold during matching *** experiments were conducted to compare the proposed method with the traditional *** results indicate that:(1)the overall matching accuracy of each evaluation indicator exceeds 90%;(2)the overall matching accuracy increases by 6–12%after an M:N matching pattern is added,and by 4–6%following the addition of topology indicators;and(3)the proper buffer threshold is about twice the average value of the closest distance from all nodes.

关键词： Improved probabilistic relaxation multi-scale road network matching topology constraint M:N matching pairs matching accuracy

PROPERTIES OF FeMnSiCrNi SHAPE MEMORY ALLOYS

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Chinese Journal of Mechanical Engineering 1998年第1期11卷 30-34,54页

作者： Li, jianchen Zhao, Ming Jiang, Qing Jilin Univ of Technology Changchun China

Some mechanical and thermal properties of FeMnSiCrNi shape memory alloys are studied The results show that Fe 14Mn 6Si 9Cr 5Ni alloy among the alloys studied has the best SME with an absolute recovery strain of 6 2% when training method is used The preexisting ε martensite (thermal and stress induced)is beneficial to the shape memory effect Up to a critical prestrain with a critical training time,the absolute recovery strain increases. Any further increase of prestrain or training time leads to the appearance of α′ phase identified by superelasticity measurement Alloys with good SME also have good creep and stress relaxation resistance,and hence possible industrial application for couplings

关键词： FeMnSiCrNi alloy Mechanical property Shape memory effect Calorimetric measurement

Direction navigability analysis of geomagnetic field based on Gabor filter

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Journal of Systems Engineering and Electronics 2018年第2期29卷 378-385页

作者： XIAO Jing DUAN Xiusheng QI Xiaohui WANG jianchen Army Engineering University Shijiazhuang 050003China Government Representative Office Northwestern Polytechnical UniversityXi’an 710065China

Direction navigability analysis is a supplement to the navigability analysis theory, in which extraction of the direction suitable-matching features(DSMFs) determines the evaluation performance. A method based on the Gabor filter is proposed to estimate the direction navigability of the geomagnetic field. First,the DSMFs are extracted based on the Gabor filter’s ***, in the view of pattern recognition, the classification accuracy in fault diagnosis is introduced as the objective function of the hybrid particle swarm optimization(HPSO) algorithm to optimize the Gabor filter’s parameters. With its guidance, the DSMFs are extracted. Finally, a direction navigability analysis model is established with the support vector machine(SVM), and the performances of the models under different objective functions are discussed. Simulation results show the parameters of the Gabor filter have a significant influence on the DSMFs, which, in turn, affects the analysis results of direction navigability. Moreover, the risk of misclassification can be effectively reduced by using the analysis model with optimal Gabor filter parameters. The proposed method is not restricted in geomagnetic navigation, and it also can be used in other fields such as terrain matching and gravity navigation.

关键词： geomagnetic navigation navigability analysis direction navigability Gabor filter direction suitable-matching feature