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On-Line Scheduling on Parallel Machines to Minimize the Makespan

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Journal of Systems Science & Complexity 2016年第2期29卷 472-477页

作者： LI Songsong zhang yuzhong School of Management Qufu Normal University

This paper considers two parallel machine scheduling problems, where the objectives of both problems are to minimize the makespan, and the jobs arrive over time, on two uniform machines with speeds 1 and s （s 〉 1）, and on m identical machines, respectively. For the first problem, the authors show that the on-line LPT algorithm has a competitive ratio of （1 ＋ √5）/2 ≈ 1.6180 and the bound is tight. Furthermore, the authors prove that the on-line LPT algorithm has the best possible competitive ratio if s ≥ 1.8020. For the second problem, the authors present a lower bound of （15 - √17）/8 ≈ 1.3596 on the competitive ratio of any deterministic on-line algorithm. This improves a previous result of 1.3473.

关键词： Lower bound on-line algorithm scheduling.

APPROXIMATION SCHEMES FOR SCHEDULING A BATCHING MACHINE WITH NONIDENTICAL JOB SIZE

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Journal of Systems Science & Complexity 2007年第4期20卷 592-600页

作者： Xianzhao zhang yuzhong zhang Zhigang CAO Zengxia CAI Department of Mathematics Linyi Normal University Linyi 276000 China College of Operations Research and Management Qufu Normal University Rizhao 276826 China Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

In this paper we study the problem of scheduling a batching machine with nonidentical job sizes. The jobs arrive simultaneously and have unit processing time. The goal is to minimize the total completion times. Having shown that the problem is NP-hard, we put forward three approximation schemes with worst case ratio 4, 2, and 3/2, respectively.

关键词： Approximation scheme batching machine size worst case ratio.

Wearable Leg Movement Monitoring System for High-Precision Real-Time Metabolic Energy Estimation and Motion Recognition

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Research 2024年第2期2023卷 417-429页

作者： Jinfeng Yuan yuzhong zhang Shiqiang Liu Rong Zhu State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Comprehensive and quantitative assessment of human physical activity in daily life is valuable for healthcare,especially for those who suffer from obesity and neurological disorders or are at high risk of *** wearable devices,e.g.,smartwatches,are insufficient and inaccurate for monitoring highly dynamic limb movements and assessing human ***,we report a new wearable leg movement monitoring system incorporating a custom-made motion sensor with machine learning algorithm to perceive human motion accurately and comprehensively during diverse walking and running *** system enables real-time multimodal perceptions of personal identity,motion state,locomotion speed,and energy expenditure for wearers.A general law of extracting real-time metabolic energy from leg movements is verified although individual gaits show *** addition,we propose a novel sensing configuration combining unilateral lower leg movement velocity with its angular rate to achieve high accuracy and good generalizability while simplifying the wearable *** performances in personal identification(accuracy of 98.7%)and motion-state recognition(accuracy of 93.7%)are *** wearable system also exhibites high-precision real-time estimations of locomotion speed(error of 3.04%to 9.68%)and metabolic energy(error of 4.18%to 14.71%)for new subjects across various time-varying *** wearable system allows reliable leg movement monitoring and quantitative assessment of bodily kinematic and kinetic behaviors during daily activities,as well as safe identity authentication by gait parameters,which would greatly facilitate smart life,personal healthcare,and rehabilitation training.

关键词： smart enable monitoring

Strong stability of Nash equilibria in load balancing games

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Science China Mathematics 2014年第7期57卷 1361-1374页

作者： CHEN Bo LI SongSong zhang yuzhong Centre for Discrete Mathematics and Its Applications Warwick Business SchoolUniversity of Warwick School of Management Qufu Normal University

We study strong stability of Nash equilibria in load balancing games of m(m 2)identical servers,in which every job chooses one of the m servers and each job wishes to minimize its cost,given by the workload of the server it chooses.A Nash equilibrium(NE)is a strategy profile that is resilient to unilateral *** an NE in such a game is ***,an NE assignment is not stable against coordinated deviations of several jobs,while a strong Nash equilibrium(SNE)*** study how well an NE approximates an *** any job assignment in a load balancing game,the improvement ratio(IR)of a deviation of a job is defined as the ratio between the pre-and post-deviation *** NE is said to be aρ-approximate SNE(ρ1)if there is no coalition of jobs such that each job of the coalition will have an IR more thanρfrom coordinated deviations of the *** it is already known that NEs are the same as SNEs in the 2-server load balancing game,we prove that,in the m-server load balancing game for any given m 3,any NE is a(5/4)-approximate SNE,which together with the lower bound already established in the literature yields a tight approximation *** closes the final gap in the literature on the study of approximation of general NEs to SNEs in load balancing *** establish our upper bound,we make a novel use of a graph-theoretic tool.

关键词： load balancing game Nash equilibrium strong Nash equilibrium approximate strong Nash equilibrium

Ultrapermeable membranes based on connected cluster of hollow polydimethylsiloxane nanoparticles for gas separation

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Particuology 2023年第8期79卷 45-53页

作者： Xiaoli Ding Fangfang Tan Hongyong Zhao Qingping Xin yuzhong zhang State Key Laboratory of Separation Membranes and Membrane Processes National Center for International Joint Research on Separation MembranesTiangong UniversityTianjin300387China Tianjin Key Laboratory of Hollow Fiber Membrane Materials and Processes(Tiangong University) Tianjin300387China

Mixed matrix membranes(MMMs)with the performance between the matrix and the filler is a promising strategy for membranes with excellent gas *** this study,the hollow polydimethylsiloxane nanoparticles were synthesized and then incorporated with the poly(oxide ethylene)monomer and tri-functional cross-linker to form mixed matrix membranes by in situ *** hollow nanoparticles formed the independent closed nanocavities in membranes,which enhanced the gas permeability contributed by both the improved diffusivity and *** high loading,the hollow polydimethylsiloxane nanoparticle was converted into the continuous phase with the cross-linked poly(oxide ethylene)as the dispersed *** preferred to permeate through the connected cluster of hollow polydimethylsiloxane nanoparticles,finally leading to ultrahigh gas per-meabilities far going beyond the instinct values of polydimethylsiloxane and the cross-linked poly(oxide ethylene).The optimized membrane with 34 wt%hollow nanoparticles loadings exhibited ultrahigh permeabilities with the values of 44186 Barrer for CO_(2) and 11506 Barrer for O_(2),accompanied with a CO_(2)/N_(2) selectivity of 9.9 and an O_(2)/N_(2) selectivity of 2.6,which exceeded the 2008 Robeson upper bound for O_(2)/N_(2) and located at the 2008 Robeson upper bound for CO_(2)/N_(2).

关键词： Hollow nanoparticles Polydimethylsiloxane nanoparticles Mixed matrix membranes Nanocavity Gas separation

Uniform Parallel-Machine Scheduling with Time Dependent Processing Times

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Journal of the Operations Research Society of China 2013年第2期1卷 239-252页

作者： Juan Zou yuzhong zhang Cuixia Miao School of Management Qufu Normal UniversityRizhaoShandongChina School of Mathematical Sciences Qufu Normal UniversityQufuShandongChina

We consider several uniform parallel-machine scheduling problems in which the processing time of a job is a linear increasing function of its starting *** objectives are to minimize the total completion time of all jobs and the total load on all *** show that the problems are polynomially solvable when the increasing rates are identical for all jobs;we propose a fully polynomial-time approximation scheme for the standard linear deteriorating function,where the objective function is to minimize the total load on all *** also consider the problem in which the processing time of a job is a simple linear increasing function of its starting time and each job has a delivery *** objective is to find a schedule which minimizes the time by which all jobs are delivered,and we propose a fully polynomial-time approximation scheme to solve this problem.

关键词： Scheduling Uniform machine Linear deterioration Fully polynomial time approximation scheme

ON-LINE SCHEDULING OF UNIT TIME JOBS WITH REJECTION ON UNIFORM MACHINES

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Journal of Systems Science & Complexity 2008年第1期21卷 114-118页

作者： Shoupeng LIU yuzhong zhang Binzhou Medical University Yantai 264003 China. zhang Institute of Operations Research Qufu Normal University Rizhao 276826 China.

The authors consider the problem of on-line scheduling of unit execution time jobs on uniform machines with rejection penalty. The jobs arrive one by one and can be either accepted and scheduled, or be rejected. The objective is to minimize the total completion time of the accepted jobs and the total penalty of the rejection jobs. The authors propose an on-line algorithm and prove that the competitive ratio is 1/2 （2 W √3） ≈ 1.86602.

关键词： Competitive ratio on-line scheduling uniform machine.

Gas permeation properties of a metallic ion-cross-linked PIM-1 thin-film composite membrane supported on a UV-cross-linked porous substrate

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2477-2486页

作者： Hongyong Zhao Lizhong Feng Xiaoli Ding Xiaoyao Tan yuzhong zhang State Key Laboratory of Separation Membranes and Membrane Processes/National Center for International Joint Research on Separation Membranes Tianjin Polytechnic UniversityTianjin 300387China School of Environmental and Chemical Engineering Tianjin Polytechnic UniversityTianjin 300387China Institute of Separation Matenal and Process Control School of Material Science and Engmeering Tianjin Polytechnic UniversityTianjin 300387China

Metallic ion-cross-linked polymer of intrinsic microporosity(PIM-1) thin-film composite(TFC) membranes supported on an ultraviolet(UV)-cross-linked porous substrate were fabricated. The UV-cross-linked porous substrate was prepared via polymerization-induced phase separation. The PIM-1 TFC membranes were fabricated via a dip-coating procedure. Metallic ion-cross-linked PIM-1 TFC membranes were fabricated by hydrolyzing the PIM-1 TFC membrane in an alkali solution and then cross-linking it in a multivalent metallic ion solution. The pore size and porous structures were evaluated by low-temperature N_2 adsorption–desorption analysis. The membrane structure was investigated by field-emission scanning electron microscopy. The effects of heat treatment and pore-forming additives on the gas permeance of the UV-cross-linked porous substrate are reported. The effects of different pre-coating treatments on the gas permeance of the metallic ion-cross-linked PIM-1 TFC membrane are also discussed. The metallic ion-crosslinked PIM-1 TFC membrane displayed high CO_2/N_2 selectivity(23) and good CO_2 permeance(1058 GPU).

关键词： Gas separation Polymerization-induced phase separation UV-cross-linked porous substrate Metallic ion-cross-linked PIM-1TFC membrane

Gene cloning and sequence analysis of the cold-adapted chaperones DnaK and DnaJ from deep-sea psychrotrophic bacterium Pseudoalteromonas sp. SM9913

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Acta Oceanologica Sinica 2007年第6期26卷 91-100页

作者： ZHAO Dianli CHEN Xiulan HE Hailun SHI Mei zhang yuzhong State Key Laboratory of Microbial Technology Marine Biotechnology Research Center Shandong University Jinan 250100 China

Pseudoalteromonas sp. SM9913 is a phychrotmphic bacterium isolated from the deep-sea sediment. The genes encoding chaperones DnaJ and DnaK of P. sp. SM9913 were cloned by normal PCR and TAIL - PCR （GenBank accession Nos DQ640312, DQ504163 ）. The chaperones DnaJ and DnaK from the strain SM9913 contain such conserved domains as those of many other bacteria, and show some cold-adapted characteristics in their structures when compared with those from psychro-, meso-and themophilic bacteria. It is indicated that chaperones DnaJ and DnaK of P. sp. SM9913 may be adapted to low temperature in deep-sea and function well in assisting folding, assembling and translocation of proteins at low temperature. This research lays a foundation for the further study on the cold-adapted mechanism of chaperones DnaJ and DnaK of cold-adapted microorganisms.

关键词： cold-adapted chaperone DnaJ DnaK deep-sea Pseudoalteromonas sp. SM9913 gene cloning sequence analysis