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AN EFFECTIVE CONTINUOUS ALGORITHM FOR APPROXIMATE SOLUTIONS OF LARGE SCALE MAX-CUT PROBLEMS

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Journal of Computational Mathematics 2006年第6期24卷 749-760页

作者： cheng-xian xu Xiao-liang Feng-min xu Department of Mathematics Xi 'an Jiaotong University Xi ' an 710049 China

An effective continuous algorithm is proposed to find approximate solutions of NP-hard max-cut problems. The algorithm relaxes the max-cut problem into a continuous nonlinear programming problem by replacing n discrete constraints in the original problem with one single continuous constraint. A feasible direction method is designed to solve the resulting nonlinear programming problem. The method employs only the gradient evaluations of the objective function, and no any matrix calculations and no line searches are required. This greatly reduces the calculation cost of the method, and is suitable for the solution of large size max-cut problems. The convergence properties of the proposed method to KKT points of the nonlinear programming are analyzed. If the solution obtained by the proposed method is a global solution of the nonlinear programming problem, the solution will provide an upper bound on the max-cut value. Then an approximate solution to the max-cut problem is generated from the solution of the nonlinear programming and provides a lower bound on the max-cut value. Numerical experiments and comparisons on some max-cut test problems （small and large size） show that the proposed algorithm is efficient to get the exact solutions for all small test problems andwell satisfied solutions for most of the large size test problems with less calculation costs.

关键词： Max-cut problems Algorithm Feasible direction method Laplacian matrix,Eigenvectors.

A FEASIBLE DIRECTION ALGORITHM WITHOUT LINE SEARCH FOR SOLVING MAX-BISECTION PROBLEMS

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Journal of Computational Mathematics 2005年第6期23卷 619-634页

作者： Feng-min xu cheng-xian xu Hong-gang xue Department of Mathematics of Faculty of Science Xi'an Jiaotong University Xi'an 710049 China

This paper concerns the solution of the NP-hard max-bisection problems. NCP functions are employed to convert max-bisection problems into continuous nonlinear programming problems. Solving the resulting continuous nonlinear programming problem generates a solution that gives an upper bound on the optimal value of the max-bisection problem. From the solution, the greedy strategy is used to generate a satisfactory approximate solution of the max-bisection problem. A feasible direction method without line searches is proposed to solve the resulting continuous nonlinear programming, and the convergence of the algorithm to KKT point of the resulting problem is proved. Numerical experiments and comparisons on well-known test problems, and on randomly generated test problems show that the proposed method is robust, and very efficient.

关键词： Max-Bisection problem Feasible direction algorithm NCP function Convergence

A TRUST REGION-TYPE METHOD FOR SOLVINGMONOTONE VARIATIONAL INEQUALITY

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Journal of Computational Mathematics 2000年第1期18卷 13-24页

作者： Xi-ming Liang cheng-xian xu Ji-xin Qian Institute of Industrial Process Control National Lab of Industrial Control TechnologyZhejiang UniversityHangzhou 310027China School of Science Xi’an Jiaotong UniversityXi’an 710049China

Presents a study which proposed to introduce a trust region-type modification of Newton method for the monotone inequality problem using merit function. Concepts of monotone mapping; Proof of convergence of algorithm ... 详细信息

关键词： variational inequality problem trust region method global convergence quadratic convergence

Failure behavior of protective organic coatings under corrosive conditions

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中国有色金属学会会刊：英文版 2004年第z1期14卷 395-404页

作者： ZHANG xian-cheng xu Bin-shi WANG Hai-dou WU Yi-xiong National Key Laboratory of Remanufacturing Academy of Armored Forces Engineering Beijing 100072 China National Key Laboratory of Remanufacturing Academy of Armored Forces Engineering Beijing 100072 China National Key Laboratory of Remanufacturing Academy of Armored Forces Engineering Beijing 100072 China School of Materials Science and Engineering Shanghai Jiaotong University Shanghai 200030 China

Recent research activities on the formation of micro-defects and porosity in organic coatings were reviewed. The mechanisms of aggressive ionic conduction through organic coatings were analyzed. The micro-mechanisms for the failure behavior of coatings under corrosive environments were discussed in detail. These mechanisms included blistering (i. e. osmotic blistering, anodic blistering and cathodic blistering) in the coating, wet-adhesion loss at the substrate/coating interface, cathodic delamination of coating from the substrate. Based on these researches, it was found that the failure behavior of organic coatings is closely related to the micro-defects in coatings, regardless of the failure mode. Additionally, the general failure mode of a coating system was proposed to interpret the failure behavior of organic in corrosion environments. The topics discussed can provide some insights into the development of a methodology for designing fail-safe coating systems.

关键词： organic coating micro-defect porosity failure mechanism failure mode

A Continuation Algorithm for Max-Cut Problem

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Acta Mathematica Sinica,English Series 2007年第7期23卷 1257-1264页

作者： Feng Min xu cheng xian xu Xing Si LI School of Science Xi'an Jiaotong University State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology

A continuation algorithm for the solution of max-cut problems is proposed in this paper. Unlike the available semi-definite relaxation, a max-cut problem is converted into a continuous nonlinear programming by employing NCP functions, and the resulting nonlinear programming problem is then solved by using the augmented Lagrange penalty function method. The convergence property of the proposed algorithm is studied. Numerical experiments and comparisons with the Geomeans and Williamson randomized algorithm made on some max-cut test problems show that the algorithm generates satisfactory solutions for all the test problems with much less computation costs.

关键词： max-cut problem NCP function convex function augmented Lagrange penalty function method

Investigating Müller glia reprogramming in mice: a retrospective of the last decade, and a look to the future

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Neural Regeneration Research 2025年第4期20卷 946-959页

作者： Zhiyuan Yin Jiahui Kang xuan cheng Hui Gao Shujia Huo Haiwei xu Key Lab of Visual Damage and Regeneration&Restoration of Chongqing Southwest Eye HospitalSouthwest HospitalThird Military Medical University(Army Medical University)ChongqingChina

Müller glia,as prominent glial cells within the retina,plays a significant role in maintaining retinal homeostasis in both healthy and diseased *** lower vertebrates like zebrafish,these cells assume responsibility for spontaneous retinal regeneration,wherein endogenous Müller glia undergo proliferation,transform into Müller glia-derived progenitor cells,and subsequently regenerate the entire retina with restored ***,Müller glia in the mouse and human retina exhibit limited neural reprogramming.Müller glia reprogramming is thus a promising strategy for treating neurodegenerative ocular disorders.Müller glia reprogramming in mice has been accomplished with remarkable success,through various *** in molecular,genetic,epigenetic,morphological,and physiological evaluations have made it easier to document and investigate the Müller glia programming process in ***,there remain issues that hinder improving reprogramming efficiency and ***,understanding the reprogramming mechanism is crucial toward exploring factors that will improve Müller glia reprogramming efficiency,and for developing novel Müller glia reprogramming *** review describes recent progress in relatively successful Müller glia reprogramming *** also provides a basis for developing new Müller glia reprogramming strategies in mice,including epigenetic remodeling,metabolic modulation,immune regulation,chemical small-molecules regulation,extracellular matrix remodeling,and cell-cell fusion,to achieve Müller glia reprogramming in mice.

关键词： cell fusion chemical small-molecules epigenetic extracellular matrix immune metabolic mice Müller glia neurodegenerative diseases reprogramming retina regeneration

Tailoring Light–Matter Interactions in Overcoupled Resonator for Biomolecule Recognition and Detection

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Nano-Micro Letters 2025年第1期17卷 262-280页

作者： Dongxiao Li Hong Zhou Zhihao Ren cheng xu chengkuo Lee Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore Center for Intelligent Sensors and MEMS(CISM) National University of SingaporeSingapore 117608Singapore

Plasmonic nanoantennas provide unique opportunities for precise control of light–matter coupling in surface-enhanced infrared absorption(SEIRA)spectroscopy,but most of the resonant systems realized so far suffer from the obstacles of low sensitivity,narrow bandwidth,and asymmetric Fano resonance ***,we demonstrated an overcoupled resonator with a high plasmon-molecule coupling coefficient(μ)(OC-Hμresonator)by precisely controlling the radiation loss channel,the resonator-oscillator coupling channel,and the frequency detuning *** observed a strong dependence of the sensing performance on the coupling state,and demonstrated that OC-Hμresonator has excellent sensing properties of ultra-sensitive(7.25%nm^(−1)),ultra-broadband(3–10μm),and immune asymmetric Fano *** characteristics represent a breakthrough in SEIRA technology and lay the foundation for specific recognition of biomolecules,trace detection,and protein secondary structure analysis using a single array(array size is 100×100μm^(2)).In addition,with the assistance of machine learning,mixture classification,concentration prediction and spectral reconstruction were achieved with the highest accuracy of 100%.Finally,we demonstrated the potential of OC-Hμresonator for SARS-CoV-2 *** findings will promote the wider application of SEIRA technology,while providing new ideas for other enhanced spectroscopy technologies,quantum photonics and studying light–matter interactions.

关键词： Plasmonic nanoantennas Light-matter interaction Surface-enhanced infrared absorption Overcoupled Biosensing

Pretreatment red blood cell distribution width as a predictive marker for postoperative complications after laparoscopic pancreatoduodenectomy

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 143-157页

作者： xian-Rang Cao Yin-Long xu Jia-Wei Chai Kai Zheng Jun-Jie Kong Jun Liu Shun-Zhen Zheng Department of Liver Transplantation and Hepatobiliary Surgery Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021Shandong ProvinceChina Department of Breast and Thyroid Surgery Shandong Provincial Maternal and Child Health Care HospitalJinan 250014Shandong ProvinceChina

BACKGROUND Red blood cell distribution width(RDW)is associated with the development and progression of various *** To explore the association between pretreatment RDW and short-term outcomes after laparoscopic pancreatoduodenectomy(LPD).METHODS A total of 804 consecutive patients who underwent LPD at our hospital between March 2017 and November 2021 were retrospectively *** between pretreatment RDW and clinicopathological characteristics and short-term outcomes were *** Patients with higher pretreatment RDW were older,had higher Eastern Cooperative Oncology Group scores and were associated with poorer short-term outcomes than those with normal *** pretreatment RDW was an independent risk factor for postoperative complications(POCs)(hazard ratio=2.973,95%confidence interval:2.032-4.350,P<0.001)and severe POCs of grade IIIa or higher(hazard ratio=3.138,95%confidence interval:2.042-4.824,P<0.001)based on the Clavien-Dino classification *** analysis showed that high pretreatment RDW was an independent risk factor for Clavien-Dino classi-fication grade IIIb or higher POCs,a comprehensive complication index score≥26.2,severe postoperative pancreatic fistula,severe bile leakage and severe *** pretreatment RDW was positively associated with the neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio and was negatively associated with albumin and the prognostic nutritional *** Pretreatment RDW was a special parameter for patients who underwent *** was associated with malnutrition,severe inflammatory status and poorer short-term *** could be a surrogate marker for nutritional and inflammatory status in identifying patients who were at high risk of developing POCs after LPD.

关键词： Biomarker Laparoscopic pancreatoduodenectomy Postoperative complication Red blood cell distribution width Short-term outcomes

Insights into spinal muscular atrophy from molecular biomarkers

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Neural Regeneration Research 2025年第7期20卷 1849-1863页

作者： Xiaodong Xing Xinzhu Liu xiandeng Li Mi Li xian Wu Xiaohui Huang Ajing xu Yan Liu Jian Zhang Department of Clinical Pharmacy Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina College of Pharmacy Chongqing Medical UniversityChongqingChina

Spinal muscular atrophy is a devastating motor neuron disease characterized by severe cases of fatal muscle *** is one of the most common genetic causes of mortality among infants aged less than 2 *** research is currently receiving more attention,and new candidate biomarkers are constantly being *** review initially discusses the evaluation methods commonly used in clinical practice while briefly outlining their respective pros and *** also describe recent advancements in research and the clinical significance of molecular biomarkers for spinal muscular atrophy,which are classified as either specific or non-specific *** review provides new insights into the pathogenesis of spinal muscular atrophy,the mechanism of biomarkers in response to drug-modified therapies,the selection of biomarker candidates,and would promote the development of future ***,the successful utilization of biomarkers may facilitate the implementation of gene-targeting treatments for patients with spinal muscular atrophy.

关键词： biomarkers disease progression gene-targeting therapy neurofilaments Nusinersen spinal muscular atrophy(SMA) survival motor neuron therapeutic evaluation treatment outcomes