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Science Letters:Binary tree of posterior probability support vector machines

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第2期12卷 83-87页

作者： dong-li wang Jian-guo ZHENG Yan ZHOU Glorious Sun School of Business and Management Donghua University Shanghai 200051 China College of lnformation Engineering Xiangtan University Xiangtan 411105 China

Posterior probability support vector machines (PPSVMs) prove robust against noises and outliers and need fewer storage support vectors (SVs). Gonen et al. (2008) extended PPSVMs to a multiclass case by both single-machine and multimachine approaches. However, these extensions suffer from low classification efficiency, high computational burden, and more importantly, unclassifiable regions. To achieve higher classification efficiency and accuracy with fewer SVs, a binary tree of PPSVMs for the multiclass classification problem is proposed in this letter. Moreover, a Fisher ratio separability measure is adopted to determine the tree structure. Several experiments on handwritten recognition datasets are included to illustrate the proposed approach. Specifically, the Fisher ratio separability accelerated binary tree of PPSVMs obtains overall test accuracy, if not higher than, at least comparable to those of other multiclass algorithms, while using significantly fewer SVs and much less test time.

关键词： Binary tree Support vector machine Handwritten recognition Classification

Incomplete Group Divisible Designs with Block Size Four and General Index

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Acta Mathematicae Applicatae Sinica 2011年第3期27卷 407-418页

作者： li-dong wang Hai-rong Kong Hong-juan liu Department of Basic Courses Chinese People's Armed Police Force Academy Langfang 065000 China School of Science Hebei University of Technology Tianjin 300401 China Department of Computer Science and Engineering Langfang Polytechnic Institute Langfang 065000 China

In this paper, we investigate the existence of incomplete group divisible designs （IGDDs） with block size four, group-type （g, h） u and general index λ. The necessary conditions for the existence of such a design are that u ≥ 4, g ≥ 3h, λg（u 1） ≡ 0 （mod 3）, λ（g h）（u 1） ≡ 0 （mod 3）, and λu（u 1）（g 2 h 2 ） ≡ 0 （mod 12）. These necessary conditions are shown to be sufficient for all λ≥ 2. The known existence result for λ = 1 is also improved.

关键词： group divisible design incomplete group divisible design holy group divisible design

Interface associativity and energy absorption capability of anti-vibration porous Al-MM alloy core with iron alloy skin structures

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Journal of Iron and Steel Research International 2017年第7期24卷 730-736页

作者： Xu Ran Hong-wei Sun li-dong wang Yao-ming Wu School of Materials Science and Engineering Changchun University of Technology State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryCAS

The interface associativity and energy absorption capability of composite structure with anti-vibration porous Al-MM（cerium-rich mischmetal）alloy core and iron alloy skin were *** aluminum core/iron alloy skin structures were fabricated considering an iron alloy tube as its shell and closed-cell porous Al-MM alloy as its core.A peeling experiment was carried out to calculate the capacity of interfacial bonding and a compression test was carried out to determine the energy absorption *** results showed that the addition of MM significantly enhanced both the interfacial bonding and the energy absorption capacity.

关键词： Porous Al-MM alloy xpanded perlite Interface associativity Energy absorption

Influence of Chromium on Mechanical Properties and CO_2/H_2S Corrosion Behavior of P110 Grade Tube Steel

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Journal of Iron and Steel Research International 2014年第1期21卷 76-85页

作者： Hui-bin WU li-fu liU li-dong wang Yue-ting liU National Engineering Research Center of Advanced Rolling University of Science and Technology Beijing AVIC Beijing Aeronautical Manufacturing Technology Research Institute

Four kinds of P110 grade tube steels containing different chromium contents were designed to probe the in- fluence of Cr on the properties of tube steel. The microstrueture, mechanical properties and corrosion behavior of the four kinds of P110 grade tube steels were studied deeply and thoroughly. The analysis of the mechanical properties indicated that tensile strength and yield strength of the steel plates were improved, while transverse and longitudinal impact energy and elongation first increased and then decreased when Cr content rose. The impact energy and elonga tion reached the peak when Cr content was 1 ~. Cr precipitates were found only in 3 ~ Cr steel, with （Nb, Ti）（C, N） or Nb（C,N） as the core of precipitation and then grew up. The corrosion experiments demonstrated that the scales on the four steels had a two layer structure under the corrosion of CO2 and H2 S. The outer layer was mainly com- posed of FeS or FeS1 x and the inner layer consisted of FeCOa and Cr compounds. Cr was rich in the inner layer and the Cr content of the inner layer increased with the Cr content in matrix. The enriched Cr enhanced the compactness of the scales, further hindering the diffusion of ions from liquid to the surface of steel, thus reducing corrosion rate.

关键词： tube steel Cr enrichment COz/H2S corrosion corrosion scale

A preliminary study on ras protein expression in human esophageal cancer and precancerous lesions

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World Journal of Gastroenterology 2000年第2期6卷 278-280页

作者： Jian li Chang Wei Feng Zhi Guo Zhao Qi Zhou li dong wang Department of Gastroenterology the 2nd Affiliated Hospital of Henan Medical UniversityZhengzhou 450003Henan ProvinceChina Laboratory for Cancer Research Henan Medical UniversityZhengzhou 450052Henan ProvinceChina

INTRODUCTIONThe esophageal carcinoma is a common malignanttumor in linzhou City (linxian) of Henan Provincein northern *** the etiology andnatural history of csophageal carcinoma are notclear,a substantial amount of evidence has beenprovided to suggest that the development of humanesophageal squamous cell carcinomas (SCC) is amultistage progressive ***

关键词： esophageal neoplasms ras protein oncogene gene expression precancerous condition

CO_2 Corrosion and Grooving Corrosion Behavior of the ERW Joint of the Q125 Grade Tube Steel

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Journal of Iron and Steel Research International 2015年第10期22卷 943-948页

作者： li-dong wang Feng-lei liU Qing-yun ZHAO Hui-bin WU AVIC Beijing Aeronautical Manufacturing Technology Research Institute University of Science and Technology Beijing

In order to investigate the CO2 corrosion behavior and the grooving corrosion susceptibility of electric resistance welded tubes of the Q125 grade, the high temperature and high pressure autoclave was employed to conduct CO2 corrosion experiments for the welded joint. The mechanisms of grooving corrosion and the factors influencing grooving corrosion susceptibility were identified by electrochemical measurement, microstructure observation, residual stress examination, micro-region composition and orientation analysis. The CO2 corrosion results show that the corrosion resistance of the base material is the best, followed by heataffected zone and the welded seam is the worst. The grooving corrosion occurred in the welded seam, and the grooving corrosion susceptibility of welded seam is relativity high. The dominated reason for the grooving corrosion of the electric resistance welded joint is the notable inclusions consisting of MnS as the main content in the welded seam. The proportion of high-angle grain boundaries in the welding zone is higher than that of base metal and the heat affected zone, which plays an important role in the corrosion behavior of the welded seam.

关键词： welded joint grooving corrosion CO2 corrosion Q 125 grade tube steel high-angle grain boundary

Energy management for multi-microgrid system based on model predictive control

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Frontiers of Information Technology & Electronic Engineering 2018年第11期19卷 1340-1351页

作者： Ke-yong HU Wen-juan li li-dong wang Shi-hua CAO Fang-ming ZHU Zhou-xiang SHOU Qianjiang College Hangzhou Normal University MOE Key Laboratory of Special Purpose Equipment and Advanced Manufacturing Technology Zhejiang University of Technology School of Information Science and Engineering Hangzhou Normal University

To reduce the computation complexity of the optimization algorithm used in energy management of a multi-microgrid system, an energy optimization management method based on model predictive control is presented. The idea of decomposition and coordination is adopted to achieve the balance between power supply and user demand, and the power supply cost is minimized by coordinating surplus energy in the multi-microgrid system. The energy management model and energy optimization problem are established according to the power flow characteristics of microgrids. A dual decomposition approach is imposed to decompose the optimization problem into two parts, and a distributed predictive control algorithm based on global optimization is introduced to achieve the optimal solution by iteration and coordination. The proposed method has been verified by simulation, and simulation results show that the proposed method provides the demanded energy to consumers in real time, and improves renewable energy efficiency. In addition, the proposed algorithm has been compared with the particle swarm optimization(PSO) algorithm. The results show that compared with PSO, the proposed method has better performance, faster convergence, and significantly higher efficiency.

关键词： Microgrids Energy management Predictive control Renewable energy Controllable energy

Joint fuzzy background and adaptive foreground model for moving target detection

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Frontiers of Computer Science 2024年第2期18卷 93-106页

作者： Dawei ZHANG Peng wang Yongfeng dong linhao li Xin li School of Artificial Intelligence Hebei University of TechnologyTianjin 300401China Lane Department of Computer Science and Electrical Engineering West Virginia UniversityMorgantownWV 26506-6109USA

Moving target detection is one of the most basic tasks in computer *** conventional wisdom,the problem is solved by iterative optimization under either Matrix Decomposition(MD)or Matrix Factorization(MF)*** utilizes foreground information to facilitate background *** uses noise-based weights to fine-tune the *** both noise and foreground information contribute to the recovery of the *** jointly exploit their advantages,inspired by two framework complementary characteristics,we propose to simultaneously exploit the advantages of these two optimizing approaches in a unified framework called Joint Matrix Decomposition and Factorization(JMDF).To improve background extraction,a fuzzy factorization is *** fuzzy membership of the background/foreground association is calculated during the factorization process to distinguish their contributions of both to background *** describe the spatio-temporal continuity of foreground more accurately,we propose to incorporate the first order temporal difference into the group sparsity constraint *** temporal constraint is adjusted *** foreground and the background are jointly estimated through an effective alternate optimization process,and the noise can be modeled with the specific probability *** experimental results of vast real videos illustrate the effectiveness of our *** with the current state-of-the-art technology,our method can usually form the clearer background and extract the more accurate ***-noise experiments show the noise robustness of our method.

关键词： matrixdecomposition matrix factorization generalized sparsity noise modeling

A Review on Particle Reinforced Mg Matrix Composites Fabricated by Powder Metallurgy

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 391-400页

作者： Zhiyuan liu li Jin Jian Zeng Fulin wang Fenghua wang Shuai dong Jie dong National Engineering Research Center of light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

This paper provides a comprehensive review of research progress in particle-reinforced Mg matrix composites prepared via powder *** article discusses different strategies,such as micro-sized,nano-sized particles,and multi-particle hybridization,which has been employed to enhance the performance of the *** addition,a range of preparation techniques that optimize the dispersion of the reinforcing particles are *** paper also highlights how the different configurations between the reinforcements and matrix alloy impact the composites’***,the article outlines the prospects of particles reinforced Mg matrix composites fabricated via powder metallurgy and recommends modification methods that could be explored to further develop these materials for various applications.

关键词： Magnesium matrix composites Reinforcing particle Powder metallurgy Mechanical properties Configuration