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A Rescheduling Method for Operation Time Delay Disturbance in Steelmaking and Continuous Casting Production Process

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Journal of Iron and Steel Research International 2012年第12期19卷 33-41页

作者： yu Sheng-ping PAN Quan-ke State key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819 Liaoning China

In the steelmaking and continuous casting （SMCC） production process, operation time delay may lead to casting break or processing conflict so that the initial scheduling plan becomes unrealizable. Existing research meth- ods are difficult to guarantee the accuracy of the model and successful application to actual applications. The resched- uling problem in response to operation time delay is firstly analyzed. This is then followed by the establishment of a novel multi-obiective nonlinear programming model （MONPM）. In specifications, a three-stage rescheduling method is proposed including the batches splitting （BS）, forward scheduling method （FSM） and backward scheduling meth- od （BSM）. As a result, the real-time application shows that the proposed rescheduling method efficiently ensures the continuous casting and dramatically shortens the redundant waiting time for molten steel in very short rescheduling time.

关键词： SMCC rescheduling disturbance heuristic algorithm

Regional ecological security anddiagnosisof obstaclefactors in underdevelopedregions：acasestudy in yunnan Province,China

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Journal of Mountain Science 2017年第5期14卷 870-884页

作者： OUZhao-rong ZHUQing-ke SUNYong-yu School of Soil and Water Conservation Beijing Forestry University Beijing 100083 China School of Ecology Tourism Southwest Forestry University Kunming 650224 China The Research Institute of Resources Insects of the Chinese Academy of Forestry (RIRI) Kunming 650224 China

In order toclarify regional ecological security status and formation mechanism of regional ecological security barriers in underdeveloped regions of China,we took yunnan province as a case to evaluate its regional ecological security by using entropy matter-element model,comprehensive index and GIS spatial method,and we diagnosed itsobstacle factors through obstacle degree model. We found a low overall level of regional ecological security in yunnan. Only Kunmingfell into the good level, 68% of the regions were below the critical safe level. For the vast majority of regions in yunnan, their regional ecological security was unstable. The indexes related to per capita resources, geological and topographyenvironment, economic, and technologywere at the unsafe or dangerous *** indexes related to urban expansion, level of income, cultivated land quality were at the level of critical safety. The indexes concerning urban management capacity, airqualityand waterenvironment were at the good or ideallevel. yunnan's regional ecological security was not good due to natural obstructive environment itself, simultaneously lower backward economic and social level restricted the ability of ecological security response to manage ragile ecological environment. The results of the composite index wereroughly consistent with those of the entropy weight matterelement model. The mean values of the classification index,from high to low, were: the state index>the response index>the pressure index. The state index and the response index had a significant mutual promotion to each *** regions with good composite index, state index and response index mainly distributed in the central regions of yunnan Province. Spatial autocorrelation of regional ecological security level in yunnan was not obvious. Water resources, economic and social development were main obstacle factors of the regional ecological *** distinguishing with obstacle type, Kunming belonged to natural ecologic

关键词： Regional ecological security Pressure state-response model Entropy matter-element model Comprehensive index method Spatial heterogeneity Obstacle factors

Delay-aware downlink beamforming with discrete rate adaptation for green cloud radio access network

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The Journal of China Universities of Posts and Telecommunications 2017年第1期24卷 26-34页

作者： yu Zhi Wang ke Ji Hong School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

With the popularity of variety delay-sensitive services, how to guarantee the delay requirements for mobile users （MUs） is a great challenge for downlink beamformer design in green cloud radio access networks （C-RANs）. In this paper, we consider the problem of the delay-aware downlink beamforming with discrete rate adaptation to minimize the power consumption of C-RANs. We address the problem via a mixed integer nonlinear program （MINLP）, and then reformulate the MINLP problem as a mixed integer second-order cone program （MI-SOCP）, which is a convex program when the integer variables are relaxed as continuous ones. Based on this formulation, a deflation algorithm, whose computational complexity is polynomial, is proposed to derive the suboptimal solution. The simulation results are presented to validate the effectiveness of our proposed algorithm.

关键词： C-RAN delay-aware downlink beamfoming discrete rate adaptation green communication mixed integer second-order cone programming

The Well-Posedness of Solution to Semilinear Pseudo-parabolic Equation

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Acta Mathematicae Applicatae Sinica 2019年第2期35卷 386-400页

作者： Wei-ke WANG yu-tong WANG School of Mathematical Sciences Shanghai Jiao Tong University

In this paper, we use the Green's function method to get the pointwise convergence rate of the semilinear pseudo-parabolic equations. By using this precise pointwise structure and introducing negative index Sobolev space condition on the initial data, we release the critical index of the nonlinearity for blowing up. Our result shows that the global existence does not only depend on the nonlinearity but also the initial condition.

关键词： Green's function pointwise negative index Sobolev space

On Chevalley Restriction Theorem for Semi-reductive Algebraic Groups and Its Applications

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Acta Mathematica Sinica,English Series 2022年第8期38卷 1421-1435页

作者： ke OU Bin SHU yu Feng YAO School of Statistics and Mathematics Yunnan University of Finance and EconomicsKunming 650221P.R.China School of Mathematical Sciences East China Normal UniversityShanghai 200241P.R.China Department of Mathematics Shanghai Maritime UniversityShanghai 201306P.R.China

An algebraic group is called semi-reductive if it is a semi-direct product of a reductive subgroup and the unipotent *** a semi-reductive algebraic group naturally arises and also plays a key role in the study of modular representations of non-classical finite-dimensional simple Lie algebras in positive characteristic,and some other *** G be a connected semi-reductive algebraic group over an algebraically closed field F and g=Lie(G).It turns out that G has many same properties as reductive groups,such as the Bruhat *** this note,we obtain an analogue of classical Chevalley restriction theorem for g,which says that the G-invariant ring F[g]~G is a polynomial ring if g satisfies a certain“positivity”condition suited for lots of cases we are interested *** applications,we further investigate the nilpotent cones and resolutions of singularities for semi-reductive Lie algebras.

关键词： Semi-reductive algebraic groups semi-reductive Lie algebras Chevalley restriction theorem nilpotent cone Steinberg map Springer resolution

Effect of microstructure on the low temperature toughness of high strength pipeline steels

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International Journal of Minerals,Metallurgy and Materials 2015年第3期22卷 254-261页

作者： Yan-ping Zeng Peng-yu Zhu ke Tong School of Materials Science and Engineering University of Science and Technology Beijing CNPC Tubular Goods Research Institute

Microstructure observations and drop-weight tear test were performed to study the microstructures and mechanical properties of two kinds of industrial X70 and two kinds of industrial X80 grade pipeline steels. The effective grain size and the fraction of high angle grain boundaries in the pipeline steels were investigated by electron backscatter diffraction analysis. It is found that the low temperature toughness of the pipeline steels depends not only on the effective grain size, but also on other microstructural factors such as martensite-austenite （MA） constituents and precipitates. The morphology and size of MA constituents significantly affect the mechanical properties of the pipeline steels. Nubby MA constituents with large size have significant negative effects on the toughness, while smaller granular MA constituents have less harmful effects. Similarly, larger Ti-rich nitrides with sharp corners have a strongly negative effect on the toughness, while fine, spherical Nb-rich carbides have a less deleterious effect. The low temperature toughness of the steels is independent of the fraction of high angle grain boundaries.

关键词： high strength pipe steels microstrucmre low temperature toughness influencing factors

Biodegradable Materials for Bone Repairs:A Review

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Journal of Materials Science & Technology 2013年第6期29卷 503-513页

作者： Lili Tan Xiaoming yu Peng Wan ke Yang Institute of Metal Research Chinese Academy of Sciences72 Wenhua Road

With attractive research and development of biomaterials, more and more opportunities have been brought to the treatments of human tissue repairs. The implant is usually no need to exist in the body accompanied with the recovery or regeneration of the tissue lesions, and the long-term effect of exotic substance to human body should be reduced as lower as possible. For this purpose, biodegradable materials, including polymers, magnesium alloys and ceramics, have attracted much attention for medical applications due to their biodegradable characters in body environment. This paper in turn introduces these three different types of widely studied biodegradable materials as well as their advantages as implants in applications for bone repairs. Relevant history and research progresses are summarized.

关键词： Biomaterial Biodegradable Polymer Magnesium Ceramie Bone repair

Synergistic removal of nitrogen monoxide by non-thermal plasma and catalyst simultaneously

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Journal of Environmental Sciences 2005年第5期17卷 846-848页

作者： yu Gang yu Qi ZENG ke-si ZHAI Xiao-dong Department of Man-Machine and Environment Engineering College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016 China College of Environmental and Chemical Engineering Wuhan Institute of Science and Technology Wuhan 430074 China

An experimental system of De-NO with plasma-catalyst（Cu zeolite） was established to investigate the differences between De- NO with plasma-catalyst and De-NO only with plasma, to provide the instruction for selecting appropriate catalyst and operating condition, The characteristics of De-NO with plasma and De-NO with plasma-catalyst were investigated comparatively by experiments. The experimental results show that De-NO with plasma-catalyst has high NO removal rate; Cu zeolite is an effective catalyst which can promote NO removal rate in plasma remarkably; De-NO with plasma-catalyst should be operated at low temperature and the temperature has opposite effects on the function of catalvst and plasma; water vapor and O2 can increase the NO removal rate.

关键词： nitrogen monoxide( NO) synergistic removal non-thermal plasma catalyst De-NO

AN INNOVATIVE ORDERS-OF-MAGNITUDE AHP APPROACH OF LEADING INDUSTRIES SELECTION:CASE STUDY OF JIANGBEI INDUSTRIAL CLUSTERS IN CHINA

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Journal of Systems Science and Systems Engineering 2014年第1期23卷 1-19页

作者： ke-yu ZHU Shan-lin YANG Wei CHEN School of Management Hefei University of Technology Joseph M.Katz Graduate School of Business University of Pittsburgh

In current stage of China Industrial Transfer, how to select the leading industries is an extremely difficult decision. In this research, we study the selection problem of Jiangbei Industrial Clusters in Anhui Province. Total thirty-three industries can be transferred to Jiangbei Industrial Clusters, however due to limited capacity, Jiangbei Industrial Clusters can only accommodate a few of them. The difficulties of such decision include： 1） the decisions are qualitative within a complex and uncertain environment; 2） the number of alternatives is beyond the upper bound of comparing elements in general decision making methods. We introduce a new methodology-the Orders-of-Magnitude approach of the Analytic Hierarchy Process （OM-AHP） to solve such selection decision. The OM-AHP follows AHP philosophy to structure qualitative questions and uses ＂pivot＂ element to handle the situation when the alternatives become more than seven. By employing OM-AHP methodology, we found the modern logistics industry and ship ＆ marine equipment etc., are identified to be the leading industries; particularly, we recommend to give higher priority in modern logistics industry and the advanced equipment manufacturing industry, given these two industries could dramatically improve the overall comprehensive economic strength and significantly enhance competitive advantages of the Jiangbei Industrial Clusters.

关键词： Decision analysis AHP industrial transfer