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Symposium of Image, Signal Processing, and Artificial Vision (STSIVA)

作者： Xue Zhang Junjie Xue Junhua Zhou Guoqiang Shi Yan Yu School of Computer Science and Engineering Nanjing University of Science and Technology Nanjing China Beijing Complex Product Advanced Manufacturing Engineering Research Center Beijing Simulation Center Beijing China State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System Engineering Beijing China Science and Technology on Space System Simulation Laboratory Beijing Simulation Center Beijing China

ISBN: (数字)9781728170862

ISBN: (纸本)9781728170879

Large-scale equipment presents the characteristics of technology-intensive, knowledge-intensive and complex, which brings high investment and high risk to equipment acquisition. This paper analyzes the various components of equipment acquisition to fully apply modeling and simulation technology to each stage of it. On the basis of multi-objective optimization theory, the objective function of the lowest risk and lowest cost of simulation-based acquisition (SBA) is proposed. Then establishing a multi-objective optimization model for simulation-based acquisition according to the corresponding constraints. The nondominated sorting genetic algorithm II (NSGA II) and multi-objective particle swarm optimization (MOPSO) algorithms are used to optimize the model, and the majority voting method is used for integration. The comparison of simulation examples proves that the multi-objective optimization model oriented to SBA designed in this paper can effectively realize the optimization of each objective of SBA under cost constraints. And the feasibility and efficiency of optimization solution are guaranteed.

关键词： Analytical models Linear programming Reliability Particle swarm optimization Optimization Sorting Investment

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Enhancing Performance of Electrical Discharge Machining by Ultrafine-Grained Cu-0.5%Cr Electrode

SSRN

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SSRN 2022年

作者： Chu, Zhu Qi Wei, Kun Xia Wei, Wei Alexandrov, Igor V. An, Xu Long Wang, Dan Dan Liu, Xiang Kui School of Materials Science and Engineering Changzhou University 1 Gehu Road Changzhou213164 China School of Electronic Engineering and Intelligent Manufacturing Anqing Normal University 1314 Jixian North Road Anqing246011 China Jiangsu Key Laboratory of Materials Surface Science and Technology Advanced Functional Materials of Jiangsu Joint Laboratory for International Cooperation Changzhou University Changzhou213164 China Department of Materials Science and Physics of Metals Ufa State Aviation Technical University 12 K. Marx St. Ufa450008 Russia

Electrode is an important component that affects the performance of electrical discharge machining (EDM), It plays an important role in machining efficiency, surface quality and geometric accuracy. In this work, a new method of preparing Cu-0.5%Cr electrode by equal channel angular pressing (ECAP), deep cryogenic treatment (DCT) and aging treatment (AT) is proposed. The ultrafine-grained Cu-0.5%Cr electrode has high strength and high electrical conductivity through this process, so as to improve the machining characteristics in EDM. The surface roughness (Ra), the workpiece corner sharpness (WCS), and the electrode wear rate (EWR) were investigated. The results show that the electrode treated with 4 passes of ECAP + DCT (12h) + AT (550℃×1h) can reduce the EWR and WCS by 63.6% and 49.7%, respectively. This is due to the electrical conductivity and microhardness of Cu-0.5%Cr electrode are significantly improved through ECAP+DCT+AT. At the same time, the research shows that the treatment of the Cu-0.5%Cr electrode with 4 passes of ECAP + DCT (12h) + AT (550℃×1h) can result in the excellent machined surface quality (Ra is reduced by 53.5%) which is confirmed by the results of the scanning electron microscopy (SEM) method. Ultrafine-grained Cu-0.5%Cr electrode with an excellent combination of strength and good electrical conductivity has an outstanding processing performance. © 2022, The Authors. All rights reserved.

关键词： Surface properties

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Diffusion mechanism simulation of cloud manufacturing complex network based on cooperative game theory

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Journal of Systems Engineering and Electronics 2018年第2期29卷 321-335页

作者： GENG Chao QU Shiyou XIAO Yingying WANG Mei SHI Guoqiang LIN Tingyu XUE Junjie JIA Zhengxuan Economics and Management School Harbin Institute of Technology at Weihai Beijing Complex Product Advanced Manufacturing Engineering Research Center Beijing Simulation Center State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System Engineering Science and Technology on Space System Simulation Laboratory Beijing Simulation Center

Cloud manufacturing is a specific implementation form of the "Internet + manufacturing" strategy. Why and how to develop cloud manufacturing platform(CMP), however, remains the key concern of both platform operators and users. A microscopic model is proposed to investigate advantages and diffusion forces of CMP through exploration of its diffusion process and mechanism. Specifically, a three-stage basic evolution process of CMP is innovatively proposed. Then, based on this basic process, a more complex CMP evolution model has been established in virtue of complex network theory, with five diffusion forces identified. Thereafter, simulations on CMP diffusion have been conducted. The results indicate that, CMP possesses better resource utilization,user satisfaction, and enterprise utility. Results of simulation on impacts of different diffusion forces show that both the time required for CMP to reach an equilibrium state and the final network size are affected simultaneously by the five diffusion forces. All these analyses indicate that CMP could create an open online cooperation environment and turns out to be an effective implementation of the "Internet + manufacturing" strategy.

关键词： complex network cloud manufacturing innovation diffusion network effect Gale-Shapley algorithm cooperative game theory

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Differences of the oxidation process and secondary organic aerosol formation at low and high precursor concentrations

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Journal of Environmental Sciences 2019年第5期31卷 256-263页

作者： Tianzeng Chen Yongchun Liu Biwu Chu Changgeng Liu Jun Liu Yanli Ge Qingxin Ma Jinzhu Ma Hong He State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences

Current atmospheric quality models usually underestimate the level of ambient secondary organic aerosol(SOA), one of the possible reasons is that the precursors at different concentrations may undergo different oxidation processes and further affect SOA formation. Therefore, there is a need to perform more chamber studies to disclose the influence. In this work, SOA formation over a wide range of initial precursor concentrations(tens of ppb to hundreds of ppb levels) was investigated in a 30 m3 indoor smog chamber,and mainly through the analysis of multiple generations of VOCs detected from HR-To FPTRMS to expound the difference in the oxidation process between low and high precursor concentrations. Compared to high initial concentrations, gas-phase intermediates formed at low concentrations had a higher intensity by about one order of magnitude, and the lowvolatility compounds also had a higher formation potential due to the competition between semi-volatile intermediates and precursors with oxidants. In addition, the formed SOA was more oxidized with higher f44 value(0.14 ± 0.02) and more relevant to real atmosphere than that formed at high concentrations. This work should help to deeply understand SOA formation and improve the performance of air quality models for SOA simulation.

关键词： Secondary organic aerosol Aromatic hydrocarbons Aerosol mass spectrometer Low-volatility compounds Oxidation processes

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Numerical Stability and Compensation Method for Equivalent Controlled Source in Electromagnetic Transient simulation

Numerical Stability and Compensation Method for Equivalent C...

引用

2019 IEEE PES Innovative Smart Grid Technologies Asia, ISGT 2019

作者： Gao, Lu Ji, Feng Yan, Heming Lin, Chang Pang, Hui Li, Jihong State Key Laboratory of Advanced Power Transmission Technology Beijing Key Laboratory of DC grid Technology and Simulation Global Energy Interconnection Research Institute Co. Ltd Beijing China State Grid Zhejiang Electric Power Co. Ltd Hangzhou China

ISBN: (纸本)9781728135205

In electromagnetic transient simulation, equivalent controlled source is usually used as an alternative of the original circuit element, such as a controlled voltage source to replace the modular multilevel converter(MMC). Since a time-step delay between the control and circuit system solution, there may be numerical stability problem. By deducing the delay differential equation and calculating its characteristic values, the causes of numerical instability are explained. Finally the numeric compensation method to solve the numerical stability problem is proposed by studying the delay function through Taylor's series and Laplace transformation. © 2019 IEEE.

关键词： Time delay

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Effect of Pt-Al coating on the fatigue behavior of the single-crystal superalloy at different temperatures

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Journal of Alloys and Compounds 2025年 1035卷

作者： Jiawei Wang Zebin Bao Shuai Li Xiaolu Pang Key Laboratory of Intelligent Equipment Digital Design and Process Simulation Hebei Province Tangshan University Tangshan 063000 China Beijing Advanced Innovation Center for Materials Genome Engineering School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Institute of Materials Intelligent Technology Liaoning Academy of Materials Shenyang 110004 China

This study investigated the effect of Pt-Al coating on the fatigue behavior of a second-generation single-crystal superalloy (DD5) at different temperatures. The Pt-Al bond coat was deposited on the superalloy, and rotating-bend fatigue tests were conducted at 700 ℃ and 900 ℃. The results showed that the bond coat did not affect the fatigue life at 900 ℃ but improved the fatigue strength at 700 ℃ under low-stress amplitude. However, at high-stress amplitude, the bond coat reduced the fatigue performance at 700 ℃. The fracture morphologies and cross-sectional microstructure were characterized to understand the fatigue crack initiation and propagation mechanisms.

关键词： Bond coat Crack initiation Fatigue behavior Single-crystal superalloy Temperature effect

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Application of the asynchronous advantage actor–critic machine learning algorithm to real-time accelerator tuning

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Nuclear Science and Techniques 2019年第10期30卷 133-141页

作者： Yun Zou Qing-Zi Xing Bai-Chuan Wang Shu-Xin Zheng Cheng Cheng Zhong-Ming Wang Xue-Wu Wang Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China Laboratory for Advanced Radiation Sources and Application Tsinghua UniversityBeijing 100084China Department of Engineering Physics Tsinghua UniversityBeijing 100084China State Key Laboratory of Intense Pulsed Radiation Simulation and Effect Northwest Institute of Nuclear TechnologyXian 710000China

This paper describes a real-time beam tuning method with an improved asynchronous advantage actor–critic(A3C)algorithm for accelerator *** operating parameters of devices are usually inconsistent with the predictions of physical designs because of errors in mechanical matching and ***,parameter optimization methods such as pointwise scanning,evolutionary algorithms(EAs),and robust conjugate direction search are widely used in beam tuning to compensate for this ***,it is difficult for them to deal with a large number of discrete local *** A3C algorithm,which has been applied in the automated control field,provides an approach for improving multi-dimensional *** A3C algorithm is introduced and improved for the real-time beam tuning code for *** in which optimization is achieved by using pointwise scanning,the genetic algorithm(one kind of EAs),and the A3C-algorithm are conducted and compared to optimize the currents of four steering magnets and two solenoids in the low-energy beam transport section(LEBT)of the Xi’an Proton Application *** currents are determined when the highest transmission of a radio frequency quadrupole(RFQ)accelerator downstream of the LEBT is *** optimal work points of the tuned accelerator were obtained with currents of 0 A,0 A,0 A,and 0.1 A,for the four steering magnets,and 107 A and 96 A for the two ***,the highest transmission of the RFQ was 91.2%.Meanwhile,the lower time required for the optimization with the A3C algorithm was successfully *** with the A3C algorithm consumed 42%and 78%less time than pointwise scanning with random initialization and pre-trained initialization of weights,respectively.

关键词： Real-time beam tuning Parameter optimization Asynchronous advantage actor–critic algorithm Low-energy beam transport

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Giant electro-optic effect in chiral topological semimetal RhSi

arXiv

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arXiv 2021年

作者： Li, Zhi Gao, Yuewen Gu, Yu Zhang, Shengli Iitaka, Toshiaki Liu, W.M. MIIT key Laboratory of Advanced Display Materials and Devices Ministry of Industry and Information Technology Institute of optoelectronics & Nanomaterials Nanjing University of Science and Technology Nanjing210094 China Discrete Event Simulation Research Team RIKEN Center for Computational Science 2-1 Hirosawa Saitama Wako351-0198 Japan Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing100190 China

We studied the linear electro-optic effect of chiral topological semimetal RhSi which is characterized by high-fold chiral fermions separated in energy space. We identify that the general second order conductivity (formula presented) includes a real symmetric component and an imaginary antisymmetric component, which are from the inter-band shift and intra-band injection current with frequency ω, respectively. The (formula presented) is significantly enhanced by the high electron velocity and nontrivial band topology of chiral fermion, and modifies the phase velocity of light wave. We also predict that the electro-optic coefficient (formula presented) of chiral crystal RhSi is about 7000 pm/V at photon energy 0.01 eV and 1.1 eV, which is about 200 times that of widely used LiNbO3 crystal. The giant electro-optic coefficient renders a relatively low half-wave voltage in order of hundreds volt, and demonstrates potential application as electro-optic crystals for the wavelength in the second telecom window of optical fiber communications. Copyright © 2021, The Authors. All rights reserved.

关键词： Optical fibers

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A hyperelastic model for hollow fiber-reinforced composites at finite deformation

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Mechanics of Materials 2025年 207卷

作者： Wang, Jialin Chen, Liangbin Hao, Meirong Chen, Yang Guo, Zaoyang Liang, Jun School of Science Harbin Institute of Technology Guangdong Shenzhen518055 China School of Civil Aviation Northwestern Polytechnical University Shaanxi Xi'an710072 China Research & Development Institute of Northwestern Polytechnical University in Shenzhen Northwestern Polytechnical University Guangdong Shenzhen518063 China Division of Atmosphere and Aerospace Information Technology Beijing Institute of Technology Guangdong Zhuhai519088 China Institute of Advanced Structure Technology Beijing Institute of Technology Beijing100081 China Beijing Key Laboratory of Lightweight Multi-functional Composite Materials and Structures Beijing Institute of Technology Beijing100081 China State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing100081 China

This study introduces a micromechanics-based constitutive model to describe the effective hyperelastic behaviors of hollow fiber-reinforced composites under finite deformation. The multiplicative decomposition approach is employed to decompose a general deformation into three fundamental deformations: isochoric uniaxial deformation along the fiber direction, equi-biaxial deformation on the transverse plane, and pure shear deformation. Based on this multiplicative decomposition, the free energy density function of the composites is thus additively decomposed into the three corresponding components. Subsequently, the effective free energy density functions of the composite for triaxial deformation (composed of the isochoric uniaxial deformation along the fiber direction and equi-biaxial deformation on the transverse plane), along-fiber shear, and transverse shear are derived using a cylindrical composite element model. The total free energy density function of the composite is then obtained by summing the contributions of these decomposed deformations. To validate the proposed model, finite element simulations based on representative volume elements are conducted. The effects of fiber volume fraction, fiber/matrix stiffness ratio, and wall thickness of hollow fiber on the effective mechanical behaviors of the composites are explored. The theoretical predictions show excellent agreement with numerical results for all considered cases, demonstrating that the proposed model reliably predicts the effective mechanical response of hollow fiber-reinforced composites under finite deformation. Finally, to further validate the prediction accuracy and computational efficiency of the developed model, it is applied to the structural analysis of a cantilever beam, with results compared to those obtained using the FE2 method. This comparative analysis demonstrates again the accuracy and efficiency of the proposed approach in practical structural analysis. © 2025

关键词： Fiber reinforced plastics

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Multi-parameter mechanistic study on the influence of vaporizer fuel atomization characteristics on combustor ignition and flame propagation processes

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Energy 2025年 330卷

作者： Bolun Sun Xin Liu Shihang Xiong Bonan Sun Wenyan Song Jialing Le Jianping Li Li Wang Yahui Li Xuejian Zhu School of Power and Energy Northwestern Polytechnical University Xi'an 710129 China Hubei Key Laboratory of Advanced Aerospace Propulsion Technology System Design Institute of Hubei Aerospace Technology Academy Wuhan 430040 China AECC Hunan Aviation Powerplant Research Institute Zhuzhou 412002 China Xi'an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi'an 710119 China

To address light-round failure during ignition in the vaporizer combustor of micro and small gas turbine engine (MS-GTE), this study investigates the effects of multiple parameters on atomization characteristics using PDPA and shadowgraphy. The results indicate that the inward contraction of spray distribution promotes flame propagation within a single vaporizer but hinders it between adjacent vaporizers. Increasing the exit diameter improves turbulent shear and fuel mist distribution while reducing SMD at the spray boundary. Circumferential holes at the exit induce localized wall-attached vortices that expand spray coverage outward while reducing SMD and mitigating inward spray contraction. Higher air pressure differential promotes continuous-phase breakup and spray expansion. Elevated wall temperatures enhance atomization, though this improvement tends to saturate at higher levels. Furthermore, ignition and light-round experiments were conducted using a three-sector combustor with high-speed imaging to validate the atomization findings. Vaporizers with larger exit diameters improve atomization uniformity and fuel mist dispersion, enabling shorter ignition and light-round timing at lower fuel-air ratios. The circumferential holes expand fuel mist dispersion, filling fuel vacuum regions between adjacent vaporizers and significantly enhancing ignition and light-round performance. The dominant mechanisms in each phase determine how various vaporizer configurations influence ignition and light-round behavior.

关键词： Gas turbines

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