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A SMOOTHING CONJUGATE GRADIENT ALGORITHM FOR NONLINEAR COMPLEMENTARITY PROBLEMS

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Journal of Systems Science and Systems Engineering 2008年第4期17卷 460-472页

作者： Caiying WU guoqing chen College of Mathematics Science Inner Mongolia University Hohhot 010021 China

A PRP-type smoothing conjugate gradient method for solving large scale nonlinear complementarity problems （NCP（F）） is proposed. At each iteration, two Armijo line searches are performed, which guarantees the positive property of the smoothing parameter and minimizes the merit function formed by Fischer-Burmeister function, respectively. Global convergence is studied when F：R^n→R^n is a continuously differentiable P0 ＋ R0 function. Numerical results show that the method is efficient.

关键词： Nonlinear complementarity conjugate gradient global convergence Fischer-Burmeister function

GMAT:A Graph Modeling Method for Group Preference Prediction

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 475-493页

作者： Xiangyu Li Xunhua Guo guoqing chen International Business School Jinan UniversityZhuhai519070China School of Economics and Management Tsinghua UniversityBeijing100084China

Preference prediction is the building block of personalized services,and its implementation at the group level helps enterprises identify their target customers *** methods for preference prediction mainly focus on behavioral interactions to extract the associations between groups and products,ignoring the importance of other auxiliary records(e.g.,online reviews and social tags)in association *** paper proposes a novel method named GMAT for group preference prediction,aiming to collectively detect the sophisticated association patterns from user generated content(UGC)and behavioral *** doing so,we construct a tripartite graph to collaborate these two types of data,and design a deep-learning algorithm with mutual attention module for generating the contextualized representations of groups and *** experiments on two real-world datasets show that GMAT is superior to other baselines in terms of group preference ***,GMAT is able to improve prediction accuracy compared with its different variants,further verifying the proposed method’s effectiveness on association pattern detection.

关键词： Group preference UGC tripartite graph deep learning

Impact of Information Security Policies on Email-Virus Propagation

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Tsinghua Science and Technology 2005年第Z1期10卷 803-810页

作者： YUAN Hua chen guoqing School of Economics and Management Tsinghua University Beijing 100084 China School of Economics and Management Tsinghua University Beijing 100084 China

Aimed at tracing out the email-virus propagation rules in communication network, this paper extends the traditional epidemiological model (i. e., SEIR) by taking into account the behavior of email users, such as email checking frequency and anti-virus information security policies, and discusses the factors that affect the email-virus propagation in an organization. With the extended SEIR model, namely E-SEIR, three aspects of information security policies (i. e., immunization, information security training,and user recovery support) are investigated in terms of their impacts on the email virus propagation. The results show that the E-SEIR model is suitable to reflect the propagation pattern of email virus, and may also be used in anti-virus policies simulation and evaluation.

关键词： email virus propagation simulation E-SEIR model information security policy epidemiological

Service-Driven Coded Forward Scheme Based on Streaming Transmission Model for Lunar Space Communication Networks

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China Communications 2020年第7期17卷 15-26页

作者： Shushi Gu Ye Wang guoqing chen Shuo Shi School of Electronic and Information Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China Peng cheng Laboratory Shenzhen 518055China School of Electronic and Information Engineering Harbin Institute of TechnologyHarbin 150001China

With the rapid development of lunar exploration,a large amount of scientific data and media stream service needs to be transmitted through Lunar Space Communication Networks(LSCNs).Due to limited transmitter power and intermittent,long delay and packet loss connections,the reliable and efficient multi-priority services’transmission in LSCNs becomes an urgent ***,we propose a Streaming Transmission Model(STM)based on temporal and spatial topology graph to describe the delay and energy consumption for data transmission in ***,we further devise a Coded Forward Scheme based on STM,termed CFS-STM,to achieve multi-priority service in two steps:i).Link Stability Function(LSF)is established by solving an optimization problem to choose the appropriate single-hop ***).Raptor code is employed to further save delay and energy with adjustable code-rate according to the different channel *** results show that,CFS-STM can significantly improve the transmission efficiency of multi-service priority streaming delivery in LSCNs.

关键词： Streaming service delay

Finite-Element Simulation and Experimental Research of the Hot-Press Sintering of Nano-Sized Ceramic Powders

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Journal of Materials Science & Technology 2003年第Z1期19卷 40-42页

作者： guoqing chen Kaifeng ZHANG Guofeng WANG Yandong YU Department of Materials Engineering Harbin Institute of Technology Harbin 150001 China Department of Materials Engineering Harbin Institute of Technology Harbin 150001 China Department of Materials Engineering Harbin Institute of Technology Harbin 150001 China Department of Materials Engineering Harbin Institute of Technology Harbin 150001 China

Numerical simulation of hot-press sintering of nano-sized ceramic powders was introduced by the commercial finite element code ***. The powder plastic model and the thermo-mechanical coupled quadrilateral element were developed and adopted in the simulation. The mechanical and thermal properties of the nano-sized alumina based powders were *** addition, the experimental research and numerical simulation of the sintering process of different initial densities were carried out. The stress state in sintering of green compacts with different initial densities was analyzed by the densification *** reason for the density fluctuations of as-sintered ceramic bulks was found out.

关键词： Sintering, Finite element method, Green compacts, Stress

Effect of drum structure on particle mixing behavior based on DEM method

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Particuology 2023年第3期74卷 74-91页

作者： Ganggang Xu Yong Zhang Xigang Yang guoqing chen Baosheng Jin Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing210096China State Key Laboratory of Clean and Efficient Coal-fired Power Generation and Pollution Control China Energy Science and Technology Research Institute Co.Ltd.Nanjing210023China

The optimization of the drum structure is beneficial to improve the particle motion and mixing in rotary *** this work,two kinds of drum structures,Lacy cylinder drum(LC)and Lacy-lifters cylinder drum(LLC),are developed on the basic of cylinder drum to enhance the heat transfer *** particle motion and mixing process are simulated by DEM *** on the grid independence and model validation,the contact number between particles and wall,particle velocity profile,thickness of active layer,particle exchange coefficient,particle concentration profile and mixing index are *** influences of the drum structure and the operation parameters are further *** results show that the contact number between particles and wall is improved in LC and LLC compared to cylinder *** particle velocity in LC is higher than that in cylinder drum at high rotating speed,and the particle velocity of the particle falling region is significantly improved in *** to cylinder drum and LC,the thickness of active layer in LLC is smaller,while the local particle mixing quality is proved to be the best in the active *** addition,the particle exchange coefficients between static region and active region in the three drums are compared and LLC is found tending to weaken the particle ***,the fluctuations of particle concentration in the active region,static region,and boundary region are weakened in LLC,and the equilibrium state is reached *** addition,the overall particle mixing performance in cylinder drum,LC and LLC is *** particle mixing performance in cylinder drum is the worst,while the difference in mixing quality of LC and LLC depends on the operation conditions.

关键词： Rotating drum Drum structure Particle velocity profile Thickness of active layer Particle mixing

Numerical Investigation of the Angle of Attack Effect on Cloud Cavitation Flow around a Clark-Y Hydrofoil

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2947-2964页

作者： Di Peng guoqing chen Jiale Yan Shiping Wang College of Engineering Peking UniversityBeijing100871China College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China

Cavitation is a prevalent phenomenon within the domain of ship and ocean engineering,predominantly occurring in the tail flow fields of high-speed rotating propellers and on the surfaces of high-speed underwater *** re-entrant jet and compression wave resulting from the collapse of cavity vapour are pivotal factors contributing to cavity ***,these phenomena significantly modulate the evolution of cavitation *** this paper,numerical investigations into cloud cavitation over a Clark-Y hydrofoil were conducted,utilizing the Large Eddy Simulation(LES)turbulence model and the Volume of Fluid(VOF)method within the OpenFOAM *** analysis of results obtained at different angles of attack is undertaken.A discernible augmentation in cavity thickness is observed concomitant with the escalation in attack angle,alongside a progressive intensification in pressure at the leading edge of the hydrofoil,contributing to the suction *** results can serve as a fundamental point of reference for gaining a deeper comprehension of cloud cavitation dynamics.

关键词： Cloud cavitation re-entrant jet compression wave clark-Y hydrofoil

Intra-Organizational Social Media and Employee Idea Generation:Analysis based on the Spanning-Relevance Framework

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Journal of Systems Science and Systems Engineering 2022年第6期31卷 649-676页

作者： Benjiang Lu Xunhua Gu Nianlong Luo Xueli Wang guoqing chen School of Business Nanjing UniversityNanjing 210093China School of Economics and Management Tsinghua UniversityBeijing 10084China Information Technology Center Tsinghua University Beijing 100084China China Retail Research Center School of Economics and ManagementTsinghua UniversityBeijing 100084China

Intra-organizational social media platforms are expected to help build a flexible corporate stage that facilitates employees'communication and leverages creative idea ***,whether and how these systems can expedite the creativity of employees remains *** paper attempts to address the impacts of employees'social relationships on intra-organizational social media on their idea generation quantity and *** upon the extant literature in the fields of information systems and organizational behavior,a theoretical model is postulated on the basis of analyzing the attributes of social ties and exchanged information content in light of a two-dimensional framework that juxtaposes boundary spanning and work *** model is empirically tested using data obtained from two internal application systems of a large telecommunications *** results validate that employees'online social relationships with different attributes are discriminably associated with their group identification and proactive ***,proactive creativity and group identification both show the positive impacts on idea generation quantity,whereas only proactive creativity has a significant positive impact on idea generation *** findings contribute to the literature on intra-organizational social media and employee idea generation,by uncovering the links among employees'online social relationships,mental processes,and idea generation.

关键词： Intra-organizational social media online social relationship idea generation group identification proactivecreativity

A bilateral heterogeneous graph model for interpretable job recommendation considering both reciprocity and competition

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Frontiers of Engineering Management 2024年第1期11卷 128-142页

作者： Xiaowei SHI Qiang WEI guoqing chen School of Economics and Management Tsinghua UniversityBeijing 100084China

Amidst the inefficiencies of traditional job-seeking approaches in the recruitment ecosystem, the importance of automated job recommendation systems has been magnified. However, existing models optimized to maximize user clicks for general product recommendations prove inept in addressing the unique challenges of job recommendation, namely reciprocity and competition. Moreover, sparse data on online recruitment platforms can further negatively impact the performance of existing job recommendation algorithms. To counteract these limitations, we propose a bilateral heterogeneous graph-based competition iteration model. This model comprises three integral components: 1) two bilateral heterogeneous graphs for capturing multi-source information from people and jobs and alleviating data sparsity, 2) fusion strategies for synthesizing attributes and preferences to produce mutually beneficial job matches, and 3) a competition-enhancing strategy for dispersing competition realized through a two-stage optimization algorithm. Augmented by granular attention mechanisms for enhanced interpretability, the model’s efficacy, competition dispersion, and interpretability are validated through rigorous empirical evaluations on a real-world recruitment platform.

关键词： job recommendation competition reciprocity interpretability