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Scheduling a Bounded Parallel-Batching Machine with Incompatible Job Families and Rejection

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Journal of the Operations Research Society of China 2014年第4期2卷 499-510页

作者： Shi-Sheng Li Ren-xia chen College of Science Zhongyuan University of TechnologyZhengzhou 450007China

We study a scheduling problem with incompatible job families and rejection on a parallel-batching machine,where the objective is to minimize the makespan of all accepted jobs plus the total penalty of all rejected *** provide a polynomial-time algorithm for the case where all jobs have identical release dates and a pseudo-polynomial-time algorithm for the case where the number of distinct release dates is *** also present a 2-approximation algorithm and a polynomial-time approximation scheme for the general problem.

关键词： Parallel-batching scheduling Incompatible job families Rejection Approximation algorithm

Hamilton-Jacobi-Bellman equations and dynamic programming for power-optimization of a multistage heat engine system with generalized convective heat transfer law

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Chinese Science Bulletin 2011年第11期56卷 1147-1157页

作者： xia ShaoJun chen LinGen SUN FengRui Postgraduate School Naval University of Engineering Wuhan 430033 China

A multistage endoreversible Carnot heat engine system operating between a finite thermal capacity high-temperature fluid reservoir and an infinite thermal capacity low-temperature environment with generalized convective heat transfer law [q∝(ΔT) m ] is investigated in this *** control theory is applied to derive the continuous Hamilton-Jacobi-Bellman (HJB) equations,which determine the optimal fluid temperature configurations for maximum power output under the conditions of fixed initial time and fixed initial temperature of the driving *** on the universal optimization results,the analytical solution for the Newtonian heat transfer law (m=1) is also *** there are no analytical solutions for the other heat transfer laws (m≠1),the continuous HJB equations are discretized and dynamic programming algorithm is performed to obtain the complete numerical solutions of the optimization *** relationships among the maximum power output of the system,the process period and the fluid temperature are discussed in *** results obtained provide some theoretical guidelines for the optimal design and operation of practical energy conversion systems.

关键词： HJB方程动态规划算法发动机系统对流换热功率优化雅可比广义多级

Side Chain Engineering of Sulfonated Poly(arylene ether)s for Proton Exchange Membranes

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Chinese Journal of Polymer Science 2020年第6期38卷 644-652页

作者： xiang Zhang Zhi-Wen Li xia-Lin chen Dong-Yang chen Yu-Ying Zheng College of Materials Science and Engineering Fuzhou UniversityFuzhou 3501116China PowerChina Railway Construction Co. LtdBeijing 100037China

Proton conductivity of proton exchange membranes(PEMs)strongly relies on microscopic morphology,which can be modulated by engineering the distribution of ionic ***,poly(arylene ether)s with densely distributed allyl functionalities are polymerized from a tetra-allyl bisphenol A *** subsequent thiol-ene addition with sodium 3-mercapto-1-propanesulfonate yields comb-shaped sulfonated fluorinated poly(arylene ether)s(SFPAEs)with ion exchange capacities(lECs)ranging from 1.29 mmol·g^-1 to 1.78 mmol g^-*** SFPAEs exhibit superior proton conductivity over the whole temperature range,which is attributed to the enhanced hydrophilic/hydrophobic phase separation as evidenced by small angle X-ray scattering *** SFPAE-4-40 with an IEC of 1.78 mmol·g^-1 shows the largest proton conductivity of 93 mS-crrr1 at room temperature under fully hydrated condition,higher than that of Nafion ***,the vanadium redox flow battery(VRFB)assembled with SFPAE-4-40 separator exhibits higher energy efficiency than the VRFB assembled with Nafion 212.

关键词： Proton exchange membrane Thiol-ene addition Side-chain engineering Phase separation Vanadium redox flow battery

Highly Selective Diphoshinoamine/Cr(III) Catalysts for Ethylene Tetramerization

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Chinese Chemical Letters 2006年第3期17卷 358-360页

作者： Tao JIANG Hong xia chen Ying Nan NING Wei chen School of Chemistry ＆ Chemical Daqing Petroleum Institute Daqing 163318 SINOPEC Beijing Research Institute of Chemical Industry Beijing 100013

Two novel diphoshinoamine ligands have been synthesized. Combination of Cr（Ⅲ） and methylaluminoxane（MAO） generated active catalytic system which can catalyze tetramerization of ethylene with high catalytic activi... 详细信息

关键词： Ethylene tetramerization 1-octene Cr(Ⅲ) diphoshinoamine MAO catalyst

Novel high torque bearingless two-sided rotary ultrasonic motor

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 786-792页

作者： LI xia chen Wei-shan XIE Tao LIU Jun-kao Department of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China

Applications are limited at present because the currently available ultrasonic motors (USMs) do not provide suffi-ciently high torque and power. The conventional travelling-wave USM needs the bearing to support, which required lubricant. To solve the above problem, a bearingless travelling-wave USM is designed. First, a novel structure of the two-sided USM consisting of a two-sided teeth stator and two disk-type rotors is designed. And the excitation principle of the two-sided travelling-wave USM is analyzed. Then, using ANSYS software, we set up the model of the stator to predict the excitation frequency and modal response of the stator. The shape of the vibration mode was obtained. Last, the load characteristics of the USM are measured using ex-perimental method. The maximum stall torque and the no-load speed were obtained. The results showed that the characteristics of the two-sided USM are better than those of the conventional one-sided USM.

关键词： Two-sided Ultrasonic motor (USM) Piezoelectric motor Travelling-wave Bearingless

Foreign direct investment and environmental pollution:A fiscal decentralization perspective

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Chinese Journal of Population,Resources and Environment 2021年第1期19卷 34-40页

作者： xia chen xiangdong Liang School of Economics and Management Changsha University of Science and TechnologyChangsha410114China

Based on the panel data of 272 prefecture-level cities in China from 2003 to 2017,this study used the comprehensive index of environmental pollution to measure local environmental pollution,and employed the panel simultaneous equation to analyze the relationship between fiscal decentralization,foreign direct investment,and environmental *** results showed that environmental pollution has the characteristics of time inertia and positive spatial spillover;fiscal decentralization and local government competition have a significant“race to bottom”effect on environmental pollution;and with the increase of fiscal decentralization,environmental quality will *** the interaction between foreign direct investment and environmental pollution under the system of fiscal decentralization,foreign direct investment aggravates environmental ***,if the environmental pollution in a given region is serious,the willingness of foreign investors to invest therein is lessened to a certain *** on the conditions in China,certain policy suggestions are put forward to increase environmental quality,such as building a comprehensive performance assessment mechanism that includes environmental quality,optimizing the decentralization system,and raising the threshold of foreign investment access.

关键词： Fiscal decentralization Foreign direct investment Environmental pollution Panel simultaneous equation

What decarbonized the residential building operation worldwide since the 2000s

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Petroleum Science 2022年第6期19卷 3194-3208页

作者： Min-Da Ma Min-xia chen Wei Feng Jing-Wen Huo Building Technology&Urban Systems Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720United States School of Management Science and Real Estate Chongqing UniversityChongqing400045PR China Department of Earth System Science Tsinghua UniversityBeijing100084PR China

Decarbonization in operational residential buildings worldwide has become critical in achieving the carbon neutral target due to the growing household energy *** accelerate the pace of global carbon neutrality,this study explores the operational carbon change in global residential buildings through the generalized Divisia index method and decoupling analysis,considering the decarbonization levels of residential buildings at different *** results show that(1)most of the samples showed a decrease in the total emissions from 2000 to *** for China and the United States(US),the carbon emissions in global residential building operations decreased by 7.95 million tons of carbon dioxide(MtCO_(2))per year over the study *** per gross domestic product(GDP)was the most positive driver causing the decarbonization of residential buildings,while GDP was the most negative driver.(2)Carbon intensity was essential to achieving a strong decoupling of economic development and carbon *** US almost consistently presented strong decoupling,while China showed weak decoupling over the last two decades.(3)The pace of decarbonization in global residential building operations is gradually slowing *** 2000 to 2019,decarbonization from residential buildings across 30 countries was 2094.3 MtCO_(2),with a decarbonization efficiency of 3.4%.Overall,this study addresses gaps in evaluating global decarbonization from operational residential buildings and provides a reference for evaluating building decarbonization by other emitters.

关键词： Global residential building Operational decarbonization Generalized divisia index method Decoupling elasticity Building decarbonization strategies

Fractional-order Virtual Inertia Control and Parameter Tuning for Energy-storage System in Low-inertia Power Grid

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Protection and Control of Modern Power Systems 2024年第5期9卷 70-83页

作者： Yukai Zeng Qiufan Yang Yujun Lin Yin chen xia chen Jinyu Wen State Key Laboratory of Advanced Electromagnetic Engineering Huazhong University of Science and TechnologyWuhan 430074China Department of Electronic and Electrical Engineering University of StrathclydeGlasgow G11XWU.K.

As conventional synchronous generators are replaced by large-scale converter-interfaced renewa-ble-energy sources(RESs),the electric power grid en-counters the challenge of low rotational ***-quently,system frequency deviation is exacerbated and system instability may occur when the frequency deviates beyond the acceptable *** mitigate this effect,this study proposes a virtual inertia control(VIC)strategy based on a fractional-order derivative and controller parameter-tuning *** tuning method uses the stability boundary locus and provides a stability criterion for identifying the stability region in the parameter *** controller parameters are then optimized within the identified stability region to suppress frequency deviation and enhance system *** proposed controller and tuning method is applied to a battery energy-storage system(BESS)in a low-inertia power system with the integration of ***-domain simulations are carried out to verify the stability region and compare the per-formance of the optimized proposed controller to that of the traditional integral-order *** simulation results show that the stability-analysis method is effective and that the fractional-order VIC,tuned with the pro-posed method,outperforms the traditional method in both frequency-regulation performance and parametric robustness.

关键词： Virtual inertia control frequency regulation fractional-order controller stability region parameter tuning

Reverse erasure guided spatio-temporal autoencoder with compact feature representation for video anomaly detection

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Science China(Information Sciences) 2022年第9期65卷 286-288页

作者： Yuanhong ZHONG xia chen Jinyang JIANG Fan REN School of Microelectronics and Communication Engineering Chongqing University State Grid Chongqing Electric Power Research Institute Changan Software Technology Company Changan Automobile Corp.

Video anomaly detection aims to learn normal patterns and identify the samples deviating from normal patterns as anomalies. In early research, methods based on handcrafted low-level features have been widely studied. However, the representation power of low-level features is insufficient for describing various patterns, causing a bottleneck in handcrafted-feature-based anomaly detection.

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