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Fault-free Hamiltonian cycles passing through a prescribed linear forest in 3-ary n-cube with faulty edges

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Frontiers of Mathematics in China 2014年第1期9卷 17-30页

作者： xie-Bin chen College of Mathematics and Statistics Minnan Normal University Zhangzhou 363000 China

The k-ary n-cube Qkn （n ≥2 and k ≥3） is one of the most popular interconnection networks. In this paper, we consider the problem of a fault- free Hamiltonian cycle passing through a prescribed linear forest （i.e., pairwise vertex-disjoint paths） in the 3-ary n-cube Qn^3 with faulty edges. The following result is obtained. Let E0 （≠θ） be a linear forest and F （≠θ） be a set of faulty edges in Q3 such that E0∩ F = 0 and ｜E0｜＋｜F｜ ≤ 2n - 2. Then all edges of E0 lie on a Hamiltonian cycle in Qn^3- F, and the upper bound 2n - 2 is sharp.

关键词： Hamiltonian cycle fault-tolerance 3-ary n-cube linear forest interconnection network

Numerical simulation on micromixer based on synthetic jet

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Acta Mechanica Sinica 2008年第6期24卷 629-636页

作者： Minghou Liu chen xie Xiangfeng Zhang Yiliang chen Department of Thermal Science and Energy Engineering. USTC. Hefei 230027 China

This paper studied a concept of micromixer with a synthetic jet placed at the bottom of a rectangular channel. Due to periodic ejections from and suctions into the channel, the fluids are mixed effectively. To study the effects of the inlet velocity, the jet intensity and frequency, and the jet location on the mixing efficiency, 3-D numerical simulations of the micromixer have been carried out. It has been found that when the jet intensity and the frequency are fixed, the mixing efficiency increases when Re 〈 50, and decreases when Re 〉 50 with the best mixing efficiency achieved at Re = 50. When the ratio of the jet velocity magnitude to the inlet velocity is taken as 10 and the jet frequency is 100 Hz, the mixing index reaches the highest value. It has also been found that to get better mixing efficiency, the orifice of the synthetic jet should be asymmetrically located away from the channel＇s centerline.

关键词： Micromixer Synthetic jet Mixing index

Novel,mutable site in the cerebral cavernous malformation-1 gene in Chinese sporadic intracranial cavernous malformation patients

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Neural Regeneration Research 2009年第3期4卷 236-240页

作者： Rong xie Xiancheng chen Department of Neurosurgery Huashan Hospital Fudan University Shanghai 200040 China

BACKGROUND： A cerebral cavernous malformation-1 （CCM1） gene mutation might result in functional loss of KREV interaction trapped-1 （KRIT1）, which is related to onset of cavernous malformations （CM）. However, data addressing sporadic CM in Chinese patients remains limited to date. OBJECTIVE： To analyze CCM1 mutation of Chinese patients with sporadic intracranial CM. DESIGN, TIME AND SETTING： Genetics experiment was performed in the Department of Neurosurgery, Huashan Hospital Affiliated to Fudan University between January 2004 and December 2005. PARTICIPANTS： Ninety patients with sporadic CM served as the CM group, and 30 healthy subjects were considered to be the control group. METHODS： Peripheral blood was collected from patients with CM and from control group subjects Genomic DNA was extracted, and exons 8, 9, 11, 12, 13, 15, 16, 17, and 18, as well as the related introns, were amplified using polymerase chain reaction. DNA sequences were compared with GeneBank. MAIN OUTCOME MEASURES： Abnormal mutable site of CCM1 gene in the two groups. RESULTS： Four exclusive mutations of CCM1 were detected in the CM group, with a sporadic CM mutational rate of 32% （6/19）. Of the four exclusive mutations, there was one missense mutation [exon 12, 1172C→T （S391 F）], one insertion mutation [exon 8, 704insT （K246stop）], one intervening sequence mutation （IVS12-4C→T）, and one synonymous mutation （exon 17, 1875C→T）. With the exception of 1875C→T, all mutations detected in the CM group led to functional changes of the KRIT1 protein, which was encoded by the CCM1 gene. Gene mutations were not detected in the control group. CONCLUSION： Four exclusive mutations of the CCM1 gene were determined in Chinese patients with sporadic CM, which led to functional changes or loss of the encoding KRIT1 protein. KRIT1 protein is considered to be the genetic basis of CM occurrence.

关键词： sporadic cavernous malformation cerebral cavernous malformation-1 gene mutation

Carbody Structural Lightweighting Based on Implicit Parameterized Model

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 483-487页

作者： chen Xin MA Fangwu WANG Dengfeng xie chen State Key Laboratory of Automotive Simulation and Control Jilin University Zhejiang Geely Automobile Research Institute Co. Ltd

Most of recent research on carbody lightweighting has focused on substitute material and new processing technologies rather than structures. However, new materials and processing techniques inevitably lead to higher costs. Also, material substitution and processing lightweighting have to be realized through body structural profiles and locations. In the huge conventional workload of lightweight optimization, model modifications involve heavy manual work, and it always leads to a large number of iteration calculations. As a new technique in carbody lightweighting, the implicit parameterization is used to optimize the carbody structure to improve the materials utilization rate in this paper. The implicit parameterized structural modeling enables the use of automatic modification and rapid multidisciplinary design optimization （MDO） in carbody structure, which is impossible in the traditional structure finite element method （FEM） without parameterization. The structural SFE parameterized model is built in accordance with the car structural FE model in concept development stage, and it is validated by some structural performance data. The validated SFE structural parameterized model can be used to generate rapidly and automatically FE model and evaluate different design variables group in the integrated MDO loop. The lightweighting result of body-in-white （BIW） after the optimization rounds reveals that the implicit parameterized model makes automatic MDO feasible and can significantly improve the computational efficiency of carbody structural lightweighting. This paper proposes the integrated method of implicit parameterized model and MDO, which has the obvious practical advantage and industrial significance in the carbody structural lightweighting design.

关键词： carbody structural lightweighting implicit parameterization MDO BIW

Pricing and Ordering Strategies of E-Retailers in Electronic Business Environments

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Tsinghua Science and Technology 2005年第Z1期10卷 778-789页

作者： xie Ming chen Jian Research Center for Contemporary Management School of Economics and ManagementTsinghua University Beijing 100084 China Research Center for Contemporary Management School of Economics and ManagementTsinghua University Beijing 100084 China

It is becoming increasingly evident that in the future the Internet will host large numbers of software agents that aid or even act on behalf of companies and consumers to make decisions and carry out transactions. In this paper, we develop different pricing and ordering strategies with limited information requirements for e-retailers under the electronic business environment, and study the dynamics and performance of these strategies through multi-agent simulation. The results not only reproduce some phenomena in former literature, such as the "tacit collusion" and the cyclical price wars,but also generate new findings, for example, the "tacit collusion" does not always exist among hill-climbing e-retailers, and the cyclical price wars will be suppressed when e-retailers consider their competitors'strategies. The results show that in electronic business environments, to test different strategies and evaluate their performance by simulation before they are employed into practice is of great importance.

关键词： pricing strategy ordering strategy agent-based simulation electronic business

Enhanced search sensitivity to the double beta decay of ^(136)Xe to excited states with topological signatures

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Science China(Physics,Mechanics & Astronomy) 2021年第6期64卷 41-50页

作者： chen xie Kaixiang Ni Ke Han Shaobo Wang Institute of Nuclear and Paricle Physics(INPAC) Shanghai Laboratory for Particle Physics and CosmologyKey Laboratory for Partic le Astrophysics and Cosmology(MOE)School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China ParisTech Elite Institute of Technology Shanghai Jiao Tong UniversiryShanghai 200240China

The double beta decay of ^(136)Xe to excited states of 136Ba(DBD-ES)has not yet been discovered *** experimental signature of such decays,one or two gamma rays following the beta signals,can be identified more effectively in a gaseous detector with the help of topological *** have investigated key parameters of particle trajectories of DBD-ES with Monte Carlo simulation data of the proposed PandaX-III detector as an *** background rates can be reduced by about one order of magnitude while keeping more than half of signals with topological *** estimated half-life sensitivity of DBD-ES can be improved by 1.8 times to 4.1×10^(23) year(90%C.L.).Similarly,the half-life sensitivity of neutrinoless double beta decay of ^(136)Xe to excited states of 136Ba can be improved by a factor of 4.8 with topological signatures.

关键词： neutrino double beta decay topological signatures background suppression

SSC:Gesture-based game for initial dementia examination

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第7期7卷 1253-1258页

作者： LIU Jun-fa chen Yi-qiang xie chen GAO Wen Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China Graduate School of the Chinese Academy of Sciences Beijing 100080 China College of Software Technology Zhejiang University Hangzhou 310027 China

This paper presents a novel system assisting medical dementia examination in a joyful way: the object just needs to play a popular game SSC against the computer during the examination. The SSC game’s target is to detect the player’s reacting capability, which is related closely with dementia. Our system reaches this target with some advantages: there are no temporal and spatial constraints at all. There is no cost, and it can even improve people’s mental status. Hand talk technology and EHMM gesture recognition approach are employed to realize the human computer interface. Experiments showed that this system can evaluate people’s reacting capability effectively and is helpful for initial dementia examination.

关键词： Human computer interface Hand talk Dementia Reaction capability

Synthesis and Structure of a La(Ⅲ) Complex of 1,10-Phenanthroline-2,9-dicarboxylate:a Three-dimensional Network via Hydrogen Bonding Interactions

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Chinese Journal of Structural Chemistry 2008年第2期27卷 137-142页

作者： GAO Qian xie Ya-Bo chen Yuan WANG Dao College of Environmental and Energy Engineering Beijing University of Technology Beijing 100022 China

A new La（Ⅲ） complex, {[La（L）（NO3）（H2O）3]·H2O}n （L = 1,10-phenanthroline- 2,9-dicarboxylate）, has been synthesized and structurally determined by X-ray diffraction analysis. The complex crystallizes in the monoclinic system, space group P21/c with a = 7.7358（17）, b = 8.1664（18）, c = 28.271（6） A, β= 95.184（4）°, V= 1778.6（7） A3, Z = 4, C14H14LaN3O11, Mr = 539.19, Dc = 2.014 g/cm^3, μ= 2.471 mm^-1, F（000） = 1056, the final R = 0.0350 and wR = 0.0659. In this complex, each metal center adopts a ten-coordination geometry formed by two N atoms from a ligand L and eight O atoms from three H2O molecules, a nitrate ion and carboxylates of two ligands. Each ligand adopts a N2,O3-pentdentate coordination mode using two N and two O atoms chelating a La（Ⅲ）, and using another O atom of carboxylate to bridge another La（Ⅲ） center resulting in a 1D helical chain molecule. Intermolecular strong O-H…O and weak C-H…O hydrogen bonds extend the 1D chain structure into a 3D supramolecular architecture.

关键词： hydrogen bonding 1,10-phenanthroline-2,9-dicarboxylate La(Ⅲ) complex,synthesis

What Can China Learn From Evidence-Based Educational Reform?A Comparative Review of Educational Technology Programs’Effects on Mathematics Achievement

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ECNU Review of Education 2021年第1期4卷 65-83页

作者： chen xie Institute of International and Comparative Education East China Normal University

Purpose:This review contrasts the *** Chinese mainland in terms of educational technology programs’effects on mathematics *** existing evaluation studies are assessed and compared,especially from the perspective of research ***,this review finds out what intervention programs work in these two countries and classifies evidence levels of effective ***/Approach/Methods:A systematic review and meta-analysis method is ***:The application of educational technology programs produced a better effect in Chinese mainland than in the U.S.,however,the quantity and quality of evaluation studies is concerning in Chinese *** 2010,four programs in the *** one program in Chinese mainland have qualified for strong evidence of effectiveness,which are worthy of receiving scale-up ***/Value:This is the first systematic review to contrast the *** China in terms of educational technology programs'effects on mathematics *** what works through high-quality experiments is probably the most important requirement for evidence-based reform in *** review compares the developments of the U.S.,a leader of the movement,with those of China,an undecided *** review may provide enlightenment for the undecided countries and regions.

关键词： Educational technology evidence-based reform mathematics achievement meta-analysis