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Single machine scheduling with semi-resumable machineavailability constraints

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Applied Mathematics(A Journal of Chinese Universities) 2011年第2期26卷 177-186页

作者： CHEN Yong zhang An tan Zhi-yi Department of Mathematics Zhejiang University Hangzhou 310027 China

This paper considers the semi-resumable model of single machine scheduling with anon-availability period. The machine is not available for processing during a given time interval.A job cannot be completed before the non-availability period will have to partially restartafter the machine has become available again. For the problem with objective of minimizingmakespan, the tight worst-case ratio of algorithm LPT is given, and an FPTAS is also *** the problem with objective of minimizing total weighted completion time, an approximationalgorithm with worst-case ratio smaller than 2 is presented. Two special cases of the latterproblem are also considered, and improved algorithms are given.

关键词： Scheduling Machine maintenance Approximation algorithm Worst-case analysis.

Layer construction of topological crystalline insulator LaSbTe

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Science China(Physics,Mechanics & Astronomy) 2020年第10期63卷 91-97页

作者： YuTing Qian ZhiYun tan tan zhang JiaCheng Gao ZhiJun Wang Zhong Fang Chen Fang HongMing Weng Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Physics and Electronic Science Zunyi Normal UniversityZunyi 563006China Songshan Lake Materials Laboratory Dongguan 523808China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China

Topological crystalline insulator(TCI)is one of the symmetry-protected topological *** TCI can be deformed into a simple product state of several decoupled two-dimensional(2 D)topologically nontrivial layers in its lattice respecting its crystalline symmetries called the layer construction(LC)*** this work,based on first-principles calculations we have revealed that both tetragonal LaSbTe(t-LaSbTe)and orthorhombic LaSbTe(o-LaSbTe)can be interpreted as stacking of 2 D topological insulators in each lattice *** structural phase transition from t-LaSbTe to o-LaSbTe due to soft phonon modes demonstrates how the real space change can lead to the modification of topological *** symmetry-based indicators and topological invariants have been analyzed based on *** propose that LaSbTe is an ideal example demonstrating the LC paradigm,which bridges the crystal structures in real space to the band topology in momentum space.

关键词： layer construction topological crystalline insulator topological insulator LaSbTe

Distribution and Transition of Native and Completely Unfolded Conformations in the Unfolding of Bovine Heart Cytochrome c Induced by Urea and Guanidine Hydrochloride

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Chinese Journal of Chemistry 2011年第9期29卷 1939-1946页

作者： Yang, Jianting zhang, tan Lu, Cuizhu Bian, Liujiao College of Life Science Northwest University Xi＇an Shaanxi 710069 China Weapon Industry 521 Hospital Xi＇an Shaanxi 710065 China

The unfolding of bovine heart cytochrome c induced by urea and guanidine hydrochloride was first studied through intrinsic fluorescence emission spectra and fluorescence phase diagram and the results showed that both of them separately followed a two-state model. As the simplest sample of the unfolding of protein molecules induced by denaturants, an equation was presented to show the effect of the denaturant concentrations in denaturation solu- tion on the residual activity ratios of bovine heart cytochrome c in their two-state unfolding. There are two charac- teristic unfolding parameters K and m in this equation. The former is the thermodynamic equilibrium constant of the unfolding of bovine heart cytochrome c induced by denaturants, the latter is the number of denaturant molecules associated with a bovine heart cytochrome c molecule during the unfolding procedure, and through them the distri- bution and transition of native and completely unfolded bovine heart cytochrome c conformations under different concentrations of urea or guanidine hydrochloride in denaturation solution can be accurately described.

关键词： bovine heart cytochrome c unfolding distribution and transition fluorescence spectroscopy biologi-cal activity

New Cutting Force Modeling Approach for Flat End Mill

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Chinese Journal of Aeronautics 2007年第3期20卷 282-288页

作者： WAN Min zhang Wei-hong tan Gang QIN Guo-hua Sino-French Laboratory of Concurrent Engineering The Key Laboratory of Contemporary Design ＆ Integrated Manufacturing Technology Northwestern Polytechnical University Xi＇an 710072 China

A new mechanistic cutting force model for flat end milling using the instantaneous cutting force coefficients is proposed. An in-depth analysis shows that the total cutting forces can be separated into two terms: a nominal component independent of the runout and a perturbation component induced by the runout. The instantaneous value of the nominal component is used to calibrate the cutting force coefficients. With the help of the perturbation component and the cutting force coefficients obtained above, the cutter runout is identified. Based on simulation and experimental results, the validity of the identification approach is demonstrated. The advantage of the proposed method lies in that the calibration performed with data of one cutting test under a specific regime can be applied for a great range of cutting conditions.

关键词： runout cutting force flat end mill calibration cutting force coefficient

CONCEPTUAL MODELING BASED ON LOGICAL EXPRESSION AND EVOLVEMENT

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Chinese Journal of Mechanical Engineering 2007年第1期20卷 64-68页

作者： YI Guodong zhang Shuyou tan Jianrong JI Yangjian State Key Laboratory of CAD ＆ CG Zhejiang University Hangzhou 310027 China

Aiming at the problem of abstract and polytype information modeling in product conceptual design, a method of conceptual modeling based on logical expression and evolvement is presented. Based on the logic expressions of the product conceptual design information, a fimction/logic/strucmre mapping model is set up. First, the fimction semantics is transformed into logical expressions through fimction/logic mapping. Second, the methods of logical evolvement are utilized to describe the fimction analysis, fimction/strucmre mapping and structure combination. Last, the logical structure scheme is transformed into geometrical sketch through logic/structure mapping. The conceptual design information and modeling process are described uniformly with logical methods in the model, and an effective method for computer aided conceptual design based on the model is implemented.

关键词： Conceptual modeling Function/logic/structure mapping Logical evolvement

NUMERICAL SIMULATION OF 2D HORIZONTAL COOLING WATER DISCHARGE IN GENERALIZED CURVILINEAR COORDINATE

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Journal of Hydrodynamics 2006年第1期18卷 91-96页

作者： XIE Zuo-tao zhang Xiao-feng tan Guang-ming YANG Fang-li State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072 China

2D horizontal model is one of the major mathematical methods for the research on cooling water discharge from the power plant. In this paper, the shallow water equations are transformed under the generalized curvilinear coordinate system and the elliptic differential equations are used to generate curvilinear grids, so a model in generalized curviline ar coordinate is presented to simulate 2D horizontal cooling water, Governing equations of the model are discretized by finite volume method, and non-staggered grids and SIMPLE algorithm are introduced to simplify the program during the discretization. This model is used to simulate the movement of cooling water in a simplified meandering channel and a natural channel, calculating results indicate this model can correctly reflect the movement rules of cooling water, which verifies the model can be applied in engineering practice.

关键词： cooling water generalized curvilinear coordinate non-staggered grids numerical simulation SIMPLE algorithm

Atomic packing and short-to-medium range order evolution of Zr-Pd metallic glass

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Chinese Science Bulletin 2011年第36期56卷 3908-3911页

作者： QI Li LIU Mei zhang ShiLiang zhang XinYu tan ChunLin State Key Laboratory of Metastable Materials Science ＆ Technology Yanshan University Qinhuangdao 066004 China

A larger-scale Zr70Pd30 alloy system has been simulated using molecular dynamics (MD) to investigate structure evolution in Zr70Pd30 metallic glass. The simulated pair distribution function of Zr70Pd30 metallic glass agrees well with the experimental results. Voronoi polyhedron analysis indicates that the icosahedra are not randomly distributed in space,but form characteristic intercrossed icosahedral clusters with medium-range order. Intercrossed icosahedral clusters are the dominant local configurations in Zr70Pd30 metallic glass and probably cause the quasicrystalline phase discovered in Zr70Pd30 metallic glass.

关键词：金属玻璃中程 Voronoi 演化包装原子二十面体分子动力学

ONE-AND TWO-DIMENSIONAL COUPLED HYDRODYNAMICS MODEL FOR DAM BREAK FLOW

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Journal of Hydrodynamics 2007年第6期19卷 769-775页

作者： YANG Fang-li zhang Xiao-feng tan Guang-ming State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China

1-D and 2-D mathematical models for dam break flow were established and verified with the measured data in laboratory. The 1-D and 2-D models were then coupled, and used to simulate the dam break flow from the reservoir tail to the dam site, the propagation of dam break waves in the downstream channel, and the submergence of dam break flow in the downstream town with the hydrodynamics method. As a numerical example, the presented model was employed to simulate dam break flow of a hydropower station under construction. In simulation, different dam-break durations, upstream flows and water levels in front of dam were considered, and these influencing factors of dam break flow were analyzed, which could be referenced in planning and designing hydropower stations.

关键词： dam-break flow hydrodynamics model 1-D and 2-D coupled model dam-break duration upstream flow,water level before dam

Linear Algebra and Multilinear Algebra

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Frontiers of Mathematics in China 2016年第3期11卷 509-510页

作者： Liqun QI Yimin WEI Changqing XU tan zhang Department of Applied Mathematics The Hong Kong Polytechnic University Hong Kong China School of Mathematical Sciences Fudan University Shanghai 200433 China School of Mathematics and Physics Suzhou University of Science and Technology Suzhou 215009 China Department of Mathematics and Statistics Murray State University Murray KY 42071-0009 USA

The 2014 International Conference on Tensors, Matrices and Their Applications （TMA 2014） was held at Suzhou University of Science and Technology （USTS）, Suzhou, China, December 17-19, 2014. The academic committee ... 详细信息

关键词： LINEAR algebras TENSOR algebra MATRICES