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971.
A locally connected spanning tree of a graph G is a spanning tree T of G such that the set of all neighbors of v in T induces a connected subgraph of G for every v∈V(G). The purpose of this paper is to give linear-time algorithms for finding locally connected spanning trees on strongly chordal graphs and proper circular-arc graphs, respectively. 相似文献
972.
基于Green函数的相空间生成泛函,导出了广义正则Ward恒等式.指出无须作出相空间生成泛函中对正则动量的路径积分,即可求得树图近似下的Feynman规则.对场的拉氏量添加一个四维散度项后,场的传播子发生了改变. 相似文献
973.
Narjès Bellamine-Ben Saoud Gloria Mark 《Computational & Mathematical Organization Theory》2007,13(2):113-146
In this paper, we investigate how complexity theory can benefit collaboration by applying an agent-based computer simulation
approach to a new form of synchronous real-time collaborative engineering design. Fieldwork was conducted with a space mission
design team during their actual design sessions, to collect data on their group conversations, team interdependencies, and
error monitoring and recovery practices. Based on the fieldwork analysis, an agent-based simulator was constructed. The simulation
shows how error recovery and monitoring is affected by the number of small group, or sidebar, conversations, and consequent
noise in the room environment. This simulation shows that it is possible to create a virtual environment with cooperating
agents interacting in a dynamic environment. This simulation approach is useful for identifying the best scenarios and eliminating
potential catastrophic combinations of parameters and values, where error recovery and workload in collaborative engineering
design could be significantly impacted. This approach is also useful for defining strategies for integrating solutions into
organizations.
Narjès Bellamine-Ben Saoud is an Associate Professor at the University of Tunis and Researcher at RIADI-GDL Laboratory, Tunisia. After Computer Science
engineering diploma (1993) of the ENSEEIHT of Toulouse, France, she received her PhD (1996), on groupware design applied to
the study of cooperation within a space project, from the University of Toulouse I, France. Her main research interests concern
studying complex systems particularly by modeling and simulating collaborative and socio-technical systems; developing Computer
Supported Collaborative Learning in tunisian primary schools; and Software Engineering. Her current reserach projects include
modeling and simulation of emergency rescue activities for large-scale accidents, modeling of epidemics and study of malaria,
simulation of collabration artifacts.
Gloria Mark is an Associate Professor in the Department of Informatics, University of California, Irvine. Dr. Mark received her Ph.D.
in Psychology from Columbia University in 1991. Prior to UCI, she was a Research Scientist at the GMD, in Bonn, Germany, a
visiting research scientist at the Boeing Company, and a research scientist at the Electronic Data Systems Center for Advanced
Research. Dr. Mark’s research focuses on the design and evaluation of collaborative systems. Her current projects include
studying worklife in the network-centric organization, multi-tasking of information workers, nomad workers, and a work in
a large-scale medical collaboratory. Dr. Mark is widely published in the fields of CSCW and HCI, is currently the program
co-chair for the ACM CSCW’06 conference and is on the editorial board of Computer Supported Cooperative Work: The Journal
of Collaborative Computing, and e-Service Qu@rterly. 相似文献
974.
We introduce root systems for those imprimitive complex reflection groups which are generated by involutory reflections, and study the associated length functions. These have many properties in common with the usual length functions for finite Weyl groups. 相似文献
975.
将数学建模思想融入工科“概率统计”教学中 总被引:17,自引:3,他引:14
提出‘概率统计”课程的一种教学改革思路,注重理论联系实际,强调应用案例中融入数学建模思想的新的教学法.改革课堂教学方法,探索新的教学模式.加强学生的实践性教学环节,培养学生的应用能力和创新能力. 相似文献
976.
A. P. Glinov A. E. Poltanov V. N. Ryndin G. I. Simonova 《Journal of Applied Mechanics and Technical Physics》2006,47(5):762-770
A procedure was developed to obtain analytical estimates of the operating modes of linear electric generators (LEGs) of the railgun type with current supply to active inductive loads. An analysis of the solutions obtained shows a low effectiveness
of using generators of this type to power geophysical dipoles in electrical prospecting (the efficiency does not exceed 20%).
Induction coil-type LEGs provide for much higher efficiency. Numerical modeling was performed of the operating modes of one design of such generators.
Versions of nonlinear-inductance LEG circuits that produce quasirectangular load current pulses and are of interest for solving electrical prospecting problems
were proposed and studied.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 5, pp. 175–184, September–October, 2006. 相似文献
977.
978.
Xiuping Li Jianjun Gao Choi Look Law Sheel Aditya 《International Journal of Infrared and Millimeter Waves》2003,24(10):1709-1718
This paper describes a simple method to check the performance of microprobe. The two-port S-parameters of the microprobe are determined by one-port S-parameters measurement using HP 8510XF Network Analyzer. Based on the measurement, an equivalent circuit model for the microprobe is presented and good agreement between the measurement results and modeling results is obtained. 相似文献
979.
980.
In this paper, we study different strategies to stabilize and accelerate the column generation method, when it is applied specifically to the variable sized bin-packing problem, or to its cutting stock counterpart, the multiple length cutting stock problem. Many of the algorithms for these problems discussed in the literature rely on column generation, processes that are known to converge slowly due to primal degeneracy and the excessive oscillations of the dual variables. In the sequel, we introduce new dual-optimal inequalities, and explore the principle of model aggregation as an alternative way of controlling the progress of the dual variables. Two algorithms based on aggregation are proposed. The first one relies on a row aggregated LP, while the second one solves iteratively sequences of doubly aggregated models. Working with these approximations, in the various stages of an iterative solution process, has proven to be an effective way of achieving faster convergence. 相似文献