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INFORMATION IDENTIFICATION IN DIFFERENT NETWORKS WITH HETEROGENEOUS INFORMATION SOURCES

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Journal of Systems Science & Complexity 2014年第1期27卷 92-116页

作者： FENG Xu zhang Wei zhang yongjie XIONG Xiong College of Management and Economics Tianjin University China Center for Social Computing Tianjin University

Traditional cheaptalk game model with homogeneous information sources provided a con clusion that dishonest information sources will not be identified if he changes strategy stochastically. In this paper, the authors incorporate different information diffusion networks and heterogeneous in formation sources into an agentbased artificial stock market. The obtained results are different with traditional results that identification ability of uninformed agents has been highly improved with diffu sion networks and heterogeneous information sources. Additionally, the authors find uninformed agents can improve identification ability only if there exists a sufficient number of heterogeneous information sources in stock market.

关键词： Agent-based heterogeneous information information diffusion networks.

Numerical Prediction on the Flow Field of Molten Steel and the Trajectory of Inclusion in Continuous Casting Mold Effected by Electromagnetic Field

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Journal of Iron and Steel Research International 1999年第1期6卷 1-7页

作者： Li Baokuan zhang yongjie He Jicheng Northeastern University Beijing University of Science and Technology

Through coupling electromagnetic field equations with turbulent flow equations,the numerical prediction has been conducted on the flow field of molten steel and the trajectory of inclusion particle in the continuous casting mold effected by electromagnetic *** difference between the maximum and the minimum of the shear stress on mold wall is used to scale the impingement strength of molten steel discharged from immersed nozzle to the solidifying shell on the narrow wall of *** flow field of molten steel in the mold is changed greatly and the impingement strength of the jet is reduced while electromagnetic field is *** is found that the successful control of flow field depends on the current and location of *** the same time,the new floating paths of inclusion particles are formed and the upward particles that are far away from the solidifying zone on the narrow wall of mold change their moving directions with the change of flow field,so that the particles can avoid being entrapped by the solidifying shell.

关键词： continuous casting mold flow field trajectory of inclusion electromagnetic control

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Numerical study of thermal history in laser aided direct metal deposition process

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Science China(Physics,Mechanics & Astronomy) 2012年第8期55卷 1431-1438页

作者： zhang yongjie YU Gang HE XiuLi Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

Temperature evolution in the laser aided direct metal deposition (LADMD) process has considerable influence on the micro-structure and properties of the final part. A 3D transient finite element model was developed to study the temperature evolution during the multilayer LADMD process. To make the property analysis from thermal history easier, a critical temperature specific to thermal history was defined and the distribution of it in the part was also discussed. The simulation results indicated that the critical temperature can make the property analysis from thermal history easier. Thermal history of all the deposited materials was similar. It was also concluded that process parameters needed to be time-varying according to the real-time temperature field during the process.

关键词： laser-aided direct metal deposition finite element modeling thermal history

Credit Rationing and the Simulation of Bank-Small and Medium Sized Firm Artificial Credit Market

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Journal of Systems Science & Complexity 2016年第4期29卷 991-1017页

作者： LIU Xuefeng zhang Wei XIONG Xiong SHEN Dehua zhang yongjie College of Management and Economics Tianjin UniversityTianjin 300072China Key Laboratory of Computation and Analytics of Complex Management Systems(CA CMS) Tianjin UniversityTianjin 300072China Departament d'Economia Universitat Jaume ICastellSn de la Plana12071Spain.

By analyzing the financing difficulties faced by the small and medium-sized firms, the paper built an artificial credit markets with the agent-based computational modeling to simulate the real world credit transactions. There are firms, banks, different risk-type projects as well as legal and supervision environments in which debt contracts constitute the financial instruments. The simulation results show that the number of collateral, average success probability of projects, and the prime interest rate have materially impact on bank's average profit, bank's capital, the overall interest rate,the number of borrowing firms, loan size, and the degree of credit rationing. These results in line with those of the classical S-W model in the sense that the relationship between bank profits and interest rates is non-monotonic as well as the relationship between credit rationing and interest rates. And thus there is an adverse selection effect in credit rationing theory.

关键词： Agent-based computational finance artificial credit market credit rationing small- and medium-sized firms.

A new robust design for imperfection sensitive stiffened cylinders used in aerospace engineering

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Science China(Technological Sciences) 2015年第5期58卷 796-802页

作者： LIANG Ke zhang yongjie SUN Qin RUESS Martin School of Aeronautics Northwestern Polytechnical University Qian Xuesen Laboratory of Space Technology China Aerospace Science and Technology Corporation Faculty of Aerospace Engineering Delft University of Technology

A knock-down factor is commonly used to take into account the obvious decline of the buckling load in a cylindrical shell caused by the inevitable imperfections. In 1968, NASA guideline SP-8007 gave knock-down factors which rely on a lower-bound curve taken from experimental data. Recent research has indicated that the NASA knock-down factors are inclined to produce very conservative estimations for the buckling load of imperfect shells, due to the limitations of the computational power and the experimental skills available five decades ago. A novel knock-down factor is proposed composed of two parts for the metallic stiffened cylinders. A deterministic study is applied to achieve the first part of the knock-down factor considering the measured geometric imperfection, the other types of imperfections are considered in the second part using a stochastic analysis. A smeared model is used to achieve the implementation of the measured geometric imperfection for the stiffened cylinder. This new robust and less conservative design for the stiffened cylinders is validated by using test results.

关键词： cylinders buckling conservative shells stochastic inevitable validated imperfect deterministic metallic

A serialized civil aircraft R&D cost estimation model considering commonality based on BP algorithm

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Chinese Journal of Aeronautics 2022年第4期35卷 253-265页

作者： yongjie zhang Kang CAO Ke LIANG Yongqi ZENG Wenjun DONG School of Aviation.Northwestern Polytechnical University Xi'an 710072China Shanghai Aircraft Design and Research Institute Shanghai 201210China

The common design of serial civil aircraft, an important strategy of modern civil aircraft research and develop-ment, minimizes the whole life cycle cost of civil aircraft through asset reuse and resource sharing. However, the existing estimating model for the R&D cost of civil aircraft ignores the effects of common design, so the value estimated by estimating derivative models is significantly inconsistent with the actual one. To solve this problem, a novel assessment method for civil aircraft commonality indicators is developed based on fuzzy set in the present study, exploiting the attributes and structural parameters of the aircraft to be assessed as input to determine the degree of membership that pertains to the commonality sub-interval as the commonality *** the BP(Back Propagation) neural network algorithm is adopted to establish the relationship between the common index and the decrease rate of the R&D cost of derivative models. The model employs over a dozen typical civil aircraft models(e.g., Boeing, Airbus, and Bombardier) as the sample data for network learning training to build a mature neural network model for estimating the R&D cost of novel derivative models. As revealed from the comparative analysis on the calculated results of the samples, the estimated results of the model given the effects of commonality in the present study exhibit higher estimation accuracy and value for future work.

关键词： BP algorithm Civil aircraft R&D cost Common indicators Fuzzy set Serialized civil aircraft

High Impedance Fault Detection Based on Attention Mechanism and Object Identification

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 197-207页

作者： yongjie zhang Xiaojun Wang Yiping Luo Dahai zhang Sohrab Mirsaeidi Jinghan He School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044China

Detection of high impedance faults(HIFs)has been traditionally a main challenge in the protection of distribution systems,since they do not generate enough current to be reliably detected by conventional over-current ***-based methods are alternative HIF detection methods which avoid threshold settings by training a classification or regression ***,most of them lack interpretability and are not compatible with various distribution *** paper proposes an object detection-based HIF detection method,which has higher visualization and can be easily applied to different ***,based on the analysis of HIFs,a Butterworth band-pass filter is designed for HIF harmonic feature ***,based on the synchronized data provided by distribution-level phasor measurement units,global HIF feature gray-scale images are formed through combining the topology information of the distribution *** further enhance the feature information,a locally excitatory globally inhibitory oscillator region attention mechanism(LEGIO-RAM)is proposed to highlight the critical feature regions and inhibit useless and fake ***,an object detection network based You Only Look Once(YOLO)v2 is established to achieve fast HIF detection and section *** obtained results from the simulation of the proposed approach on three different distribution networks and one realistic distribution network verify that the proposed method is highly effective in terms of reliability and generalization.

关键词： Attention mechanism distribution-level phasor measurement units high impedance faults object detection

Fluid-inspired field representation for risk assessment in road scenes

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Computational Visual Media 2020年第4期6卷 401-415页

作者： Xuanpeng Li Lifeng Zhu Qifan Xue Dong Wang yongjie Jessica zhang School of Instrument Science and Engineering Southeast UniversityNanjing 210096China Department of Mechanical Engineering Carnegie Mellon UniversityPittsburghPA 15213USA

Prediction of the likely evolution of traffic scenes is a challenging task because of high uncertainties from sensing technology and the dynamic *** leads to failure of motion planning for intelligent agents like autonomous *** this paper,we propose a fluid-inspired model to estimate collision risk in road ***-object states are detected and tracked,and then a stable fluid model is adopted to construct the risk ***’state spaces are used as the boundary conditions in the simulation of advection and diffusion *** have evaluated our approach on the public KITTI dataset;our model can provide predictions in the cases of misdetection and tracking error caused by *** proves a promising approach for collision risk assessment in road scenes.

关键词： fluid-inspired risk field multi-object tracking road scenes

Exploration and implementation of commonality valuation method in commercial aircraft family design

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Chinese Journal of Aeronautics 2019年第8期32卷 1828-1846页

作者： yongjie zhang Zheng YANG Xianchao MA Wenjun DONG Dayong DONG Zhaoguang TAN Shuai zhang School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Shanghai Aircraft Design and Research Institute Shanghai 200232China Beijing Aeronautical Science&Technology Research Institute Beijing 102211China

Commercial aircraft family design can reduce development costs, shorten development cycles, and expand the market coverage of aircraft. Commercial aircraft family development has become one of the most important features of modern aircraft design. This paper explores the effects of commonality on different aircraft models in a commercial aircraft family. The existing product commonality indexes are summarized and their limitations in the application to aircraft design are discussed. Then a new component commonality index is proposed based on the component decomposition structure. A model for calculating the aircraft program value is established,which considers development costs, manufacturing costs, sale price, operation costs and residual costs. The effects of aircraft commonality on time and economic costs of both development and manufacturing, and on sale price, are analyzed and quantified. The commonality evaluation strategy is obtained, which features comprehensive consideration of the aircraft program value and time costs. The break-even analysis of aircraft is proceeded on the basis of costs and price data. By using a real option method, the strategy considers the uncertainty of the aircraft program and the flexibility of the manufacturer. This strategy proves to be rational and applicable to aircraft design based on the calculation of three examples and the analysis of parameter sensitivity.

关键词： Aircraft cost Aircraft family Aircraft program value Commonality index Real option method