检索结果-内蒙古大学图书馆

Transport of Mars-Crossing Asteroids from the Quasi-Hilda Region

Physical Review Letters 2005年第23期94卷 231102-231102页

作者： Michael Dellnitz Oliver Junge Martin W. Lo Jerrold E. Marsden Kathrin Padberg Robert Preis Shane D. Ross Bianca Thiere Faculty of Computer Science Electrical Engineering and Mathematics University of Paderborn D-33095 Paderborn Germany Navigation and Mission Design Jet Propulsion Laboratory California Institute of Technology M/S 301-140L 4800 Oak Grove Drive Pasadena California 91109 USA Control and Dynamical Systems California Institute of Technology MC 107-81 Pasadena California 91125 USA Department of Aerospace and Mechanical Engineering University of Southern California Los Angeles California 90089 USA

We employ set oriented methods in combination with graph partitioning algorithms to identify key dynamical regions in the Sun-Jupiter-particle three-body system. Transport rates from a region near the 3∶2 Hilda resonance into the realm of orbits crossing Mars’ orbit are computed. In contrast to common numerical approaches, our technique does not depend on single long term simulations of the underlying model. Thus, our statistical results are particularly reliable since they are not affected by a dynamical behavior which is almost nonergodic (i.e., dominated by strongly almost invariant sets).

关键词： Astrophysics

来源：评论

学校读者我要写书评

暂无评论

Predictors of success in diagrammatic problem solving

Predictors of success in diagrammatic problem solving

引用

3rd International Conference on Diagrammatic Representation and Inference, Diagrams 2004

作者： Yoon, Daesub Narayanan, N. Hari Intelligent and Interactive Systems Laboratory Department of Computer Science and Software Engineering Auburn University AuburnAL36849 United States

ISBN: (纸本)354021268X

We conducted an eye-tracking study of mechanical problem solving from cross-sectional diagrams of devices. Response time, accuracy and eye movement data were collected and analyzed for 72 problem-solving episodes (9 subjects solving 8 problems each). Results indicate that longer response times and visually attending to more components of a device do not necessarily lead to increased accuracy. However, more focus shifts, visually attending to components in the order of causal propagation, and longer durations of visual attention allocated to critical components of the devices appear to be characteristics that separate successful problem solvers from unsuccessful ones. These findings throw light on effective diagrammatic reasoning strategies, provide empirical support to a cognitive model of comprehension, and suggest ideas for the design of information displays that support causal reasoning. © 2004, Springer-Verlag Berlin Heidelberg, All rights Reserved.

关键词： Problem solving

来源：评论

学校读者我要写书评

暂无评论

Enabling collaborative adaptation across legacy components

Enabling collaborative adaptation across legacy components

引用

3rd Workshop on Adaptive and Reflective Middleware, ARM '04

作者： Yang, Z. Zhou, Z. Cheng, B.H.C. McKinley, P.K. Software Engineering and Network Systems Laboratory Department of Computer Science and Engineering Michigan State University East Lansing MI 48824 United States

ISBN: (纸本)1581139497

software frequently needs to adapt its behavior at run time to respond to changes in its execution environment. Different software components may use different approaches to adaptation. Composing a single adaptive system from existing adaptive components requires an "adaptation infrastructure" to integrate and arbitrate adaptive behaviors. This paper proposes a model for such an infrastructure and describes the design and operation of M2, a prototype implementation. M2 uses a technique called transparent shaping to modify existing components so that they can report events of interest to the M2 core and implement appropriate responses. The architecture and communication infrastructure of M2 are described, followed by a case study in which M2 is used to construct an adaptive multimedia conferencing application from otherwise incompatible components. Copyright 2004 ACM.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Transformations for write-all-with-collision model

引用

7th International Conference on Principles of Distributed systems, OPODIS 2003

作者： Kulkarni, Sandeep S. Arumugam, Mahesh Umamaheswaran Software Engineering and Network Systems Laboratory Department of Computer Science and Engineering Michigan State University East LansingMI48824 United States

ISBN: (纸本)3540226672

In this paper, we consider a new atomicity model, write all with collision (WAC), and compare it with existing models considered in the literature. This model captures the computations in sensor networks. We show that it is possible to transform a program from WAC model into a program in read/write model, and vice versa. Further, we show that the transformation from WAC model to read/write model is stabilization preserving, and the transformation from read/write model to WAC model is stabilization preserving for timed systems. In the transformation from read/write model to WAC model, if the system is untimed (asynchronous) and processes are deterministic then under reasonable assumptions, we show that (1) the resulting program in WAC model can allow at most one process to execute, and (2) the resulting program in WAC model cannot be stabilizing. In other words, if a deterministic program cannot read then it is important that it can tell time. © Springer-Verlag Berlin Heidelberg 2004.

关键词： Stabilization

来源：评论

学校读者我要写书评

暂无评论

A market-based scheduler for JXTA-based peer-to-peer computing system

A market-based scheduler for JXTA-based peer-to-peer computi...

引用

International Conference on Computational science and its Applications, ICCSA 2004

作者： Ping, Tan Tien Sodhy, Gian Chand Yong, Chan Huah Haron, Fazilah Buyya, Rajkumar School of Computer Science Universiti Sains Malaysia Penang11800 Malaysia Grid Computing and Distributed Systems Laboratory Department of Computer Science and Software Engineering University of Melbourne Australia

ISBN: (纸本)3540220607

Peer-to-Peer (P2P) computing is said to be the next wave of computing after client-server and web-based computing. It provides an opportunity to harness a lot of idle peer-resources such as desktop computers across the Internet, for solving large-scale computing applications. Each peer is autonomous and it needs incentive for sustained contribution of its resources to P2P applications. In addition, a flexible and efficient job scheduling is needed to harvest the idle computing power as cheaply and economically as possible. This paper introduces an economic based job scheduler for mapping jobs to resources in P2P computing environment. The scheduler has been implemented with the Compute Power Market (CPM) system developed using Sun JXTA P2P technology. Our scheduler can be configured depending on users’ quality of service requirements such as the deadline and budget constraints. Our scheduler follows a hierarchy scheme. The design allows multiple consumers and multiple providers to schedule and run jobs. To allow wider support for a wide variety of applications, the system is designed to allow easy ‘plug in’ of user applications. © Springer-Verlag Berlin Heidelberg 2004.

关键词： Personal computers

来源：评论

学校读者我要写书评

暂无评论

TRAP/J: Transparent generation of adaptable java programs

引用

On the Move to Meaningful Internet systems 2004: International Conference on Cooperative Information systems, CoopIS 2004, International Conference on Distributed Objects and Applications, DOA 2004 and International Conference on Ontologies, Databases and Applications of Semantics, ODBASE 2004

作者： Masoud Sadjadi, S. McKinley, Philip K. Cheng, Betty H. C. Kurt Stirewalt, R.E. School of Computer Science Florida International University MiamiFL33199 United States Software Engineering and Network Systems Laboratory Department of Computer Science and Engineering Michigan State University East LansingMI48824 United States

ISBN: (纸本)3540236627

This paper describes TRAP/J, a software tool that enables new adaptable behavior to be added to existing Java applications transparently (that is, without modifying the application source code and without extending the JVM). The generation process combines behavioral reflection and aspect-oriented programming to achieve this goal. Specifically, TRAP/J enables the developer to select, at compile time, a subset of classes in the existing program that are to be adaptable at run time. TRAP/J then generates specific aspects and reflective classes associated with the selected classes, producing an adapt-ready program. As the program executes, new behavior can be introduced via interfaces to the adaptable classes. A case study is presented in which TRAP/J is used to introduce adaptive behavior to an existing audio-streaming application, enabling it to operate effectively in a lossy wireless network by detecting and responding to changing network conditions. © Springer-Verlag Berlin Heidelberg 2004.

关键词： Quality of service

来源：评论

学校读者我要写书评

暂无评论

TSS: A hybrid web searches

引用

Advanced Workshop on Content Computing, AWCC 2004

作者： Han, Li-Xin Chen, Gui-Hai Xie, Li Department of Mathematics Nanjing University Nanjing210093 China Department of Computer Science and Engineering Hohai University Nanjing210024 China State Key Laboratory of Novel Software Technology Nanjing University Nanjing210093 China

ISBN: (纸本)3540238980

Because of emergence of Semantic Web, It make possible for machines to understand the meaning of resources on the Web. The widespread availability of machine understandable information will impact on Information retrieval on the web. In this paper, we propose a hybrid web searches architecture, TSS, which combines the traditional search with semantic search to improve precision and recall. The components in TSS are described to support the hybrid web searches. © Springer-Verlag Berlin Heidelberg 2004.

关键词： Information retrieval

来源：评论

学校读者我要写书评

暂无评论

Automated synthesis of multitolerance

Automated synthesis of multitolerance

引用

International Conference on Dependable systems and Networks (DSN)

作者： S.S. Kulkarni A. Ebnenasir Software Engineering and Network Systems Laboratory Department of Computer Science and Engineering Michigan State University East Lansing MI USA

We concentrate on automated synthesis of multitolerant programs, i.e., programs that tolerate multiple classes of faults and provide a (possibly) different level of fault-tolerance to each class. We consider three levels of fault-tolerance: (1) failsafe, where in the presence of faults, the synthesized program guarantees safety, (2) nonmasking, where in the presence of faults, the synthesized program recovers to states from where its safety and liveness are satisfied, and (3) masking where in the presence of faults the synthesized program satisfies safety and recovers to states from where its safety and liveness are satisfied. We focus on the automated synthesis of finite-state multitolerant programs in high atomicity model where the program can read and write all its variables in an atomic step. We show that if one needs to add failsafe (respectively, nonmasking) fault-tolerance to one class of faults and masking fault-tolerance to another class of faults then such addition can be done in polynomial time in the state space of the fault-intolerant program. However, if one needs to add failsafe fault-tolerance to one class of faults and nonmasking fault-tolerance to another class of faults then the resulting problem is NP-complete. We find this result to be counterintuitive since adding failsafe and nonmasking fault-tolerance to the same class of faults (which is equivalent to adding masking fault-tolerance to that class of faults) can be done in polynomial time, whereas adding failsafe fault-tolerance to one class of faults and nonmasking fault-tolerance to a different class of faults is NP-complete.

关键词： Fault tolerance Safety Fault tolerant systems Network synthesis Polynomials software engineering Laboratories computer science State-space methods engineering profession

来源：评论

学校读者我要写书评

暂无评论

A distributed approach to topology-aware overlay path monitoring

A distributed approach to topology-aware overlay path monito...

引用

International Conference on Distributed Computing systems

作者： C. Tang P.K. McKinley Software Engineering and Network Systems Laboratory Department of Computer Science and Engineering Michigan State University East Lansing MI USA

Path probing is essential to maintain an efficient overlay network topology. However, the cost of complete probing can be as high as O(n/sup 2/), which is prohibitive in large-scale overlay networks. Recently we proposed a method that trades probing overhead for inference accuracy in sparse networks such as the Internet. The method uses physical path information to infer path quality for all of the n/spl times/(n-1) overlay paths, while actually probing only a subset of the paths. We propose and evaluate a distributed approach to implement this method. We describe a minimum diameter, link-stress bounded overlay spanning tree, which is used to collect and disseminate path quality information. All nodes in the tree collaborate to infer the quality of all paths. Simulation results show this approach can achieve a high-level of inference accuracy while reducing probing overhead and balancing link stress on the spanning tree.

关键词： Peer to peer computing Network topology Stress Probes IP networks Routing Bandwidth Delay computerized monitoring software engineering

来源：评论

学校读者我要写书评

暂无评论

Perimorph: run-time composition and state management for adaptive systems

Perimorph: run-time composition and state management for ada...

引用

International Conference on Distributed Computing systems Workshop

作者： E.P. Kasten P.K. McKinley Software Engineering and Network Systems Laboratory Department of Computer Science and Engineering Michigan State University East Lansing MI USA

We address a key issue that arises in run-time recomposition of software: the transfer of nontransient state between old components and their replacements. We focus on the concept of collateral change, which refers to the set of recomposition actions that must be applied atomically for continued correct execution of the system. We describe Perimorph, a system that supports compositional adaptation of both functional and nonfunctional concerns by explicitly addressing collateral change. The operation of Perimorph is demonstrated through the implementation and testing of a 2D/3D digital elevation mapping application that supports recomposition and handoff among networked devices with varying capabilities.

关键词： Runtime Adaptive systems Application software Distributed computing Fault tolerance software engineering Laboratories computer science Testing Middleware

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：