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Preemptive Semi-online Algorithms for Parallel Machine Scheduling with Known Total Size

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Acta Mathematica Sinica,English Series 2006年第2期22卷 587-594页

作者： Yong HE Hao ZHOU yi wei jiang State Key Lab of CAD & CG Zhejiang University Department of Mathematics Zhejiang University

This paper investigates preemptive semi-online scheduling problems on m identical parallel machines, where the total size of all jobs is known in advance. The goal is to minimize the maximum machine completion time or maximize the minimum machine completion time. For the first objective, we present an optimal semi-online algorithm with competitive ratio 1. For the second objective, we show that the competitive ratio of any semi-online algorithm is at least （2m-3）/（m-1） for any m〉2 and present optimal semi-online algorithms for m = 2, 3.

关键词： Semi-online Preemptive scheduling Competitive analysis

Optimal Preemptive Online Algorithms for Scheduling with Known Largest Size on Two Uniform Machines

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Acta Mathematica Sinica,English Series 2007年第1期23卷 165-174页

作者： Yong HE yi wei jiang Hao ZHOU Department of Mathematics Zhejiang University. Hangzhou 310027. P. R. China Faculty of Science Zhejiang Sci- Tech University Hangzhou 310018 P. R. China. Department of Mathematics Zhejiang University Hangzhou 310027. P. R. China Basic Course Department Zhejiang Shorten University Hangzhou 310015. P. R. China

In this paper, we consider the seml-online preemptive scheduling problem with known largest job sizes on two uniform machines. Our goal is to maximize the continuous period of time （starting from time zero） when both machines are busy, which is equivalent to maximizing the minimum machine completion time if idle time is not introduced. We design optimal deterministic semi-online algorithms for every machine speed ratio s ∈ [1, ∞）, and show that idle time is required to achieve the optimality during the assignment procedure of the algorithm for any s 〉（s^2 ＋ 3s ＋ 1）/（s^2 ＋ 2s ＋ 1）. The competitive ratio of the algorithms is （s^2 ＋ 3s ＋ 1）/（s^2 ＋ 2s ＋ 1）, which matches the randomized lower bound for every s ≥ 1. Hence randomization does not help for the discussed preemptive scheduling problem.

关键词： semi-online preemptive scheduling uniform machines competitive ratio

Impurities evaporation from metallurgical-grade silicon in electron beam melting process

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Rare Metals 2011年第3期30卷 274-277页

作者： WANG Qiang DONG wei TAN yi jiang Dachuan ZHANG Cong PENG Xu School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China

The purification of metallurgical-grade silicon （MG-Si） has been investigated during electron beam melting （EBM） process. The results show that the phosphorus, calcium and aluminum contents decrease significantly after melting, and magnesium is partially removed. However, no significant change in content for boron and iron has been found. Langmuir＇s equation and Henry law were used to derive the removal effi-ciency for each impurity element. The free surface temperature was estimated by the Hertz-Knudsen-Langmuir equation and silicon＇s vapor pressure equation. Good agreement was found between measured and calculated impurities＇ removal efficiency for phosphorus, calcium and aluminum, magnesium, boron and iron. The deviation between the two results was also analyzed in depth.

关键词： electron beam melting silicon evaporation impurities removal efficiency

Technology portfolio assessment for near-zero emission iron and steel industry in China

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Advances in Climate Change Research 2023年第3期14卷 469-478页

作者： wei-yi jiang Tae Yong JUNG Han-Cheng DAI Pian-Pian XIANG Graduate School of International Studies Yonsei UniversitySeoul 03722South Korea College of Environmental Science and Engineering Peking UniversityBeijing 100871China Faculty of Environment and Life Beijing University of TechnologyBeijing 100124China

China aims to peak CO_(2)emissions before 2030 and to achieve carbon neutrality before 2060;hence,industrial sectors in China are keen to figure out appropriate pathways to support the national target of carbon *** objective of this study is to explore near-zero emission pathways for the steel industry of China through a detailed technology *** innovative technology development has been simulated using the AIM-China/steel model,developed by including material-based technologies and optimal cost *** scenarios have been given in terms of different levels of production output,emission reduction and carbon ***-zero emission and carbon tax scenarios have shown that China's steel industry can achieve near-zero emission using electric furnaces and hydrogen-based direct reduction iron technologies with policy *** on these technologies,minimised production costs have been calculated,revealing that the steel produced by these technologies is ***,the feedstock cost can play a key role in these technology portfolios,especially the cost of scrap,iron ore and *** addition,the feedstock supply can have strong regional effects and can subsequently impact the allocation of steelmaking in the ***,China can achieve near-zero emissions in the steel industry,and electric furnace and hydrogen-based direct reduction iron technologies are crucial to achieving them.

关键词： Steel industry Near-zero emission Cost optimisation Climate change Carbon neutrality Technology learning

Role of hydrogen in China's energy transition towards carbon neutrality target:IPAC analysis

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Advances in Climate Change Research 2023年第1期14卷 43-48页

作者： Pian-Pian XIANG Chen-Min HE Sha CHEN wei-yi jiang Jia LIU Ke-Jun jiang College of Energy and Environment Beijing University of TechnologyBeijing 100124China Zhejian Carbon Neutral Innovation Institute Zhejiang University of TechnologyHangzhou 310014China Graduate School of International Studies Yonsei UniversitySeoul 03722South Korea Renm Consulting Co. Beijing 100038China Energy Research Institute Chinese Academy of Macro-Economic ResearchBeijing 100038China

China announced its intention to achieve carbon neutrality by 2060 in 2020,and there is an urgent need to understand the viability of emission pathways to reach this *** study presents the IPAC modelling team's scenario analysis on China's hydrogen utilisation as a key option for carbon neutrality *** contrast to other studies,this study examines the demand for hydrogen as a feedstock and process material in the industrial sector and as a source of energy in the transportation sector in relation to China's energy system *** process of manufacturing hydrogen from carbon-free power generation was also *** finding indicates that the demand for hydrogen could reach 52.4 Mt by 2050 and that the hydrogen will come from renewable power generation and nuclear energy,increasing the demand for electricity by 1884.8 TW *** are several regions in China with abundant renewable energy and low power generation costs,which will make the hydrogen-based industry competitive in these regions after 2035.

关键词： Scenario Hydrogen Carbon neutrality targets CO_(2)mitigation China

Online Scheduling with Unit Processing Times and Processing Set Restrictions

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Journal of the Operations Research Society of China 2019年第3期7卷 475-484页

作者： Yong Chen Guang-Ting Chen Long-Cheng Liu yi-wei jiang Zhi-yi Tan An Zhang Department of Mathematics Hangzhou Dianzi UniversityHangzhou 310018China School of Electronics and Information Engineering Taizhou UniversityTaizhou 318000ZhejiangChina School of Mathematical Sciences Xiamen UniversityXiamen 361005China Department of Computing Science University of AlbertaEdmontonAB T6G 2R3Canada School of Management and E-Business Zhejiang Gongshang UniversityHangzhou 310018China Department of Mathematics Zhejiang UniversityHangzhou 310027China

This paper investigates online scheduling problems with processing set *** is a sequence of jobs that are revealed one by one over list,where each job has unit processing time.A job can only be processed by a subset of the machines,namely the processing set of the *** objective is to minimize the *** m machines with two different processing sets,we propose an optimal algorithm with a competitive ratio of 3/*** three machines with inclusive processing sets,an optimal algorithm with competitive ratio 5/3 is provided.

关键词： Online scheduling Competitive ratio Processing sets

Drug-Target Interactions Prediction Based on Signed Heterogeneous Graph Neural Networks

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Chinese Journal of Electronics 2024年第1期33卷 231-244页

作者： Ming CHEN Yajian jiang Xiujuan LEI yi PAN Chunyan JI wei jiang College of Information Science and Engineering Hunan Normal University School of Computer Science Shaanxi Normal University Faculty of Computer Science and Control Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of Sciences Computer Science Department BNU-HKBU United International College

Drug-target interactions(DTIs) prediction plays an important role in the process of drug *** computational methods treat it as a binary prediction problem, determining whether there are connections between drugs and targets while ignoring relational types information. Considering the positive or negative effects of DTIs will facilitate the study on comprehensive mechanisms of multiple drugs on a common target, in this work, we model DTIs on signed heterogeneous networks, through categorizing interaction patterns of DTIs and additionally extracting interactions within drug pairs and target protein pairs. We propose signed heterogeneous graph neural networks(SHGNNs), further put forward an end-to-end framework for signed DTIs prediction, called SHGNN-DTI,which not only adapts to signed bipartite networks, but also could naturally incorporate auxiliary information from drug-drug interactions(DDIs) and protein-protein interactions(PPIs). For the framework, we solve the message passing and aggregation problem on signed DTI networks, and consider different training modes on the whole networks consisting of DTIs, DDIs and PPIs. Experiments are conducted on two datasets extracted from Drug Bank and related databases, under different settings of initial inputs, embedding dimensions and training modes. The prediction results show excellent performance in terms of metric indicators, and the feasibility is further verified by the case study with two drugs on breast cancer.

关键词： Drugs Training Proteins Measurement Message passing Prediction methods Graph neural networks

High Speed Sintering:Assessing the Influence of Energy Input on Microstructure and Mechanical Properties of Polyether Block Amide(PEBA)Parts

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Chinese Journal of Polymer Science 2024年第5期42卷 675-682,I0004,I0010页

作者： jiang-Tao Sun Zhi-Yong Fan yi-wei Mao wei Li wei Zhu Dao-Sheng Cai Qing-Song wei State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430074China National Engineering Research Centre for High Efficiency Grinding Hunan UniversityChangsha410082China Wuhan EasyMFG Technology CO. LTDWuhan430074China

High speed sintering,a new powder-bed fusion additive manufacturing technology,utilizes infrared lights(IR)to intensely heat and melt polymer *** presence of defects such as porosity,which is associated with particle coalescence,is highly dependdent on the level of energy *** study investigate the influcence of energy input on porosity and its subsequent effects on the mechanical properties and microstructures of PEBA *** parts were manufactured with a variety of lamp powers,resulting in a range of energy input levels spanning from low to ***,they underwent testing using Archimedes’method,followed by tensile *** porosity,mechanical characteristics,and energy input exhibit a strong correlation;inadequate energy input was the primary cause of pore *** the reduced IR light power resulted in the following outcomes:porosity,ultimate tensile strength,and elongation of 1.37%,7.6 MPa,and 194.2%,*** the energy input was further increased,the porosity was reduced to as low as 0.05%and the ultimate tensile strength and elongation were increased to their peak values of 233.8%and 9.1 MPa,respectively.

关键词： High speed sintering Additive manufacturing Energy input Powder bed fusion PEBA

Dynamic Crosslinked Phosphorescent Poly(vinyl alcohol)-Terpyridine Films with Enhanced Mechanical Properties and Tunable Shape Memory

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Chinese Journal of Polymer Science 2024年第10期42卷 1595-1601,I0015页

作者： Meng wei wei-Hao Feng Chen Yu Zhen-yi jiang Guang-Qiang yin wei Lu Tao Chen Key Laboratory of Advanced Marine Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China School of Chemical Sciences University of Chinese Academy of SciencesBeijing100049China School of Materials Science and Chemical Engineering Ningbo UniversityNingbo315211China

Achieving versatile room temperature phosphorescence(RTP)materials,especially with tunable mechanical properties and shape memory is attractive and essential but rarely ***,a strategy was reported to realize multi-functional RTP films with multicolor fluorescence,ultralong afterglow,adjustable mechanical properties,and shape memory through the synergistic dynamic interaction of lanthanide(Ln~Ⅲ)-terpyridine coordination,borate ester bonds,and hydrogen bondings in a poly(vinyl alcohol)(PVA)*** varying the amount of borax,the mechanical properties of the films could be finely controlled due to the change of crosslinking degree of dynamic borate ester bonds in *** assembly and disassembly of borate ester bonds upon the trigger of borax and acid were applied as reversible linkage to achieve programmable shape memory *** addition,the films displayed both fascinating multicolor fluorescence and ultralong afterglow characteristics due to the presence of Ln III doping and confinement of terpyridine in *** study provides a new avenue to impart modulable mechanical strength and shape memory to RTP materials.

关键词： Room temperature phosphorescence materials Dynamic bonds Multicolor fluorescent Tunable mechanical properties Shape memory