Verifying distributed real-time properties of embedded systems via graph transformations and model checking

Component middleware provides dependable and efficient platforms that support key functional, and quality of service (QoS) needs of distributed real-time embedded (DRE) systems. Component middleware, however, also introduces challenges for DRE system developers, such as evaluating the predictability of DRE system behavior, and choosing the right design alternatives before committing to a specific platform or platform configuration. Model-based technologies help address these issues by enabling design-time analysis, and providing the means to automate the development, deployment, configuration, and integration of component-based DRE systems. To this end, this paper applies model checking techniques to DRE design models using model transformations to verify key QoS properties of component-based DRE systems developed using Real-time CORBA. We introduce a formal semantic domain for a general class of DRE systems that enables the verification of distributed non-preemptive real-time scheduling. Our results show that model-based techniques enable design-time analysis of timed properties and can be applied to effectively predict, simulate, and verify the event-driven behavior of component-based DRE systems. This research was supported by the NSF Grants CCR-0225610 and ACI-0204028 Gabor Madl is a Ph.D. student and a graduate student researcher at the Center for Embedded Computer Systems at the University of California, Irvine. His advisor is Nikil Dutt. His research interests include the formal verification, optimization, component-based composition, and QoS management of distributed real-time embedded systems. He received his M.S. in computer science from Vanderbilt University and in computer engineering from the Budapest University of Technology and Economics. Dr. Sherif Abdelwahed received his Ph.D. degree in Electrical and Computer Engineering from the University of Toronto, Canada, in 2001. During 2000–2001, he was a research scientist with the system diagnosis group at the Rockwell Scientific Company. Since 2001 he has been with the Department of Electrical Engineering and Computer Science at Vanderbilt University as a Research Assistant Professor. His research interests include verification and control of distributed real-time systems, and model-based diagnosis of discrete-event and hybrid systems. Dr. Douglas C. Schmidt is a Professor of Computer Science, Associate Chair of the Computer Science and Engineering program, and a Senior Researcher in the Institute for Software Integrated Systems (ISIS) all at Vanderbilt University. He has published over 300 technical papers and 6 books that cover a range of research topics, including patterns, optimization techniques, and empirical analyses of software frameworks and domain-specific modeling environments that facilitate the development of distributed real-time and embedded (DRE) middleware and applications. Dr. Schmidt has served as a Deputy Office Director and a Program Manager at DARPA, where he lead the national R&D effort on middleware for DRE systems. In addition to his academic research and government service, Dr. Schmidt has over fifteen years of experience leading the development of ACE, TAO, CIAO, and CoSMIC, which are widely used, open-source DRE middleware frameworks and model-driven tools that contain a rich set of components and domain-specific languages that implement patterns and product-line architectures for high-performance DRE systems.     

ARMiner: A Data Mining Tool Based on Association Rules

In this paper,ARM iner,a data mining tool based on association rules,is introduced.Beginning with the system architecture,the characteristics and functions are discussed in details,including data transfer,concept hierarchy generalization,mining rules with negative items and the re-development of the system.An example of the tool‘s application is also shown.Finally,Some issues for future research are presented.     

An Algebraic Hardware/Software Partitioning Algorithm

Hardware and software co-design is a design technique which delivers computer systems comprising hardware and software components.A critical phase of the co-design process is to decompose a program into hardware and software .This paper proposes an algebraic partitioning algorithm whose correctness is verified in program algebra.The authors inroduce a program analysis phase before program partitioning and deveop a collection of syntax-based splitting rules.The former provides the information for moving operations from software to hardware and reducing the interaction between compoents,and th latter supports a compositional approach to program partitioning.     

Adaptive group scheduling mechanism using mobile agents in peer-to-peer grid computing environment

Peer-to-peer grid computing is an attractive computing paradigm for high throughput applications. However, both volatility due to the autonomy of volunteers (i.e., resource providers) and the heterogeneous properties of volunteers are challenging problems in the scheduling procedure. Therefore, it is necessary to develop a scheduling mechanism that adapts to a dynamic peer-to-peer grid computing environment. In this paper, we propose a Mobile Agent based Adaptive Group Scheduling Mechanism (MAAGSM). The MAAGSM classifies and constructs volunteer groups to perform a scheduling mechanism according to the properties of volunteers such as volunteer autonomy failures, volunteer availability, and volunteering service time. In addition, the MAAGSM exploits a mobile agent technology to adaptively conduct various scheduling, fault tolerance, and replication algorithms suitable for each volunteer group. Furthermore, we demonstrate that the MAAGSM improves performance by evaluating the scheduling mechanism in Korea@Home. SungJin Choi is a Ph.D. student in the Department of Computer Science and Engineering at Korea University. His research interests include mobile agent, peer-to-peer computing, grid computing, and distributed systems. Mr. Choi received a M.S. in computer science from Korea University. He is a student member of the IEEE. MaengSoon Baik is a senior research member at the SAMSUNG SDS Research & Develop Center. His research interests include mobile agent, grid computing, server virtualization, storage virtualization, and utility computing. Dr. Baik received a Ph.D. in computer science from Korea University. JoonMin Gil is a professor in the Department of Computer Science Education at Catholic University of Daegu, Korea. His recent research interests include grid computing, distributed and parallel computing, Internet computing, P2P networks, and wireless networks. Dr. Gil received his Ph.D. in computer science from Korea University. He is a member of the IEEE and the IEICE. SoonYoung Jung is a professor in the Department of Computer Science Education at Korea University. His research interests include grid computing, web-based education systems, database systems, knowledge management systems, and mobile computing. Dr. Jung received his Ph.D. in computer science from Korea University. ChongSun Hwang is a professor in the Department of Computer Science and Engineering at Korea University. His research interests include distributed systems, distributed algorithms, and mobile computing. Dr. Hwang received a Ph.D. in statistics and computer science from the University of Georgia.     

Preference update for e-commerce applications: Model,language, and processing

It is likely that customers issue requests based on out-of-date information in e-commerce application systems. Hence, the transaction failure rates would increase greatly. In this paper, we present a preference update model to address this problem. A preference update is an extended SQL update statement where a user can request the desired number of target data items by specifying multiple preferences. Moreover, the preference update allows easy extraction of criteria from a set of concurrent requests and, hence, optimal decisions for the data assignments can be made. We propose a group evaluation strategy for preference update processing in a multidatabase environment. The experimental results show that the group evaluation can effectively increase the customer satisfaction level with acceptable cost. Peng Li is the Chief Software Architect of didiom LLC. Before that, he was a visiting assistant professor of computer science department in Western Kentucky University. He received his Ph.D. degree of computer science from the University of Texas at Dallas. He also holds a B.Sc. and M.S. in Computer Science from the Renmin University of China. His research interests include database systems, database security, transaction processing, distributed and Internet computer and E-commerce. Manghui Tu received a Bachelor degree of Science from Wuhan University, P.R. China in 1996, and a Master Degree in Computer Science from the University of Texas at Dallas 2001. He is currently working toward the PhD degree in the Department of Computer Science at the University of Texas at Dallas. Mr. Tu’s research interests include distributed systems, grid computing, information security, mobile computing, and scientific computing. His PhD research work focus on the data management in secure and high performance data grid. He is a student member of the IEEE. I-Ling Yen received her BS degree from Tsing-Hua University, Taiwan, and her MS and PhD degrees in Computer Science from the University of Houston. She is currently an Associate Professor of Computer Science at the University of Texas at Dallas. Dr. Yen’s research interests include fault-tolerant computing, security systems and algorithms, distributed systems, Internet technologies, E-commerce, and self-stabilizing systems. She had published over 100 technical papers in these research areas and received many research awards from NSF, DOD, NASA, and several industry companies. She has served as Program Committee member for many conferences and Program Chair/Co-Chair for the IEEE Symposium on Application-Specific Software and System Engineering & Technology, IEEE High Assurance Systems Engineering Symposium, IEEE International Computer Software and Applications Conference, and IEEE International Symposium on Autonomous Decentralized Systems. She is a member of the IEEE. Zhonghang Xia received the B.S. degree in applied mathematics from Dalian University of Technology in 1990, the M.S. degree in Operations Research from Qufu Normal University in 1993, and the Ph.D. degree in computer science from the University of Texas at Dallas in 2004. He is now an assistant professor in the Department of Computer Science, Western Kentucky University, Bowling Green, KY. His research interests are in the area of multimedia computing and networking, distributed systems, and data mining.     

Internet Network Resource Information Model

The foundation of any network management systems is a database that contains information about the network resources relevant to the management tasks.A network information model is an abstraction of network resources,including both managed resources and managing resources,In the SNMP-based management framework,management information is defined almost exclusively from a “Device“ viewpoint,namely managing a network is equivalent to managing a collection of individual nodes.Aiming at making use of recent advances in distributed computing and in object-oriented analysis and design,the Internet management architecture can also be based on the Open Distributed Processing Reference Model(RM-ODP).The purpose of this article is to provide an Internet Network Resource Information Model.First,a layered management information architecture will be discussed.Then the Internet Network resource information model is presented.The information model is specified using object-Z.     

BCL—3：Aigh Performance Basic Communication Protocol for Commodity Superserver DAWNING—3000

This paper introduces the design and implemetation of BCL-3,a high performance low-level communication software running on a cluster of SMPs(CLUMPS) called DAWNING-3000,BCL-3 provides flexible and sufficient functionality to fulfill the communication requirements of fundamental system software developed for DAWNING-3000 while guaranteeing security,scalability,and reliability,Important features of BCL-3 are presented in the paper,including special support for SMP and heterogeneous network environment,semiuser-level communication,reliable and ordered data transfer and scalable flow control,The performance evaluation of BCL-3 over Myrinet is also given.     

Model Checking Real-Time Value-Passing Systems

In this paper, to model check real-time value-passing systems, a formal language Timed Symbolic Transition Graph and a logic system named Timed Predicate p-Calculus are proposed. An algorithm is presented which is local in that it generates and investigates the reachable state space in top-down fashion and maintains the partition for time evaluations as coarse as possible while on-the-fly instantiating data variables. It can deal with not only data variables with finite value domain, but also the so called data independent variables with infinite value domain. To authors knowledge, this is the first algorithm for model checking timed systems containing value-passing features.     

PAN: A portable,parallel Prolog: Its design,realisation and performance

PAN is a general purpose, portable environment for executing logic programs in parallel. It combines a flexible, distributed architecture which is resilient to software and platform evolution with facilities for automatically extracting and exploiting AND and OR parallelism in ordinary Prolog programs. PAN incorporates a range of compile-time and run-time techniques to deliver the performance benefits of parallel execution while rertaining sequential execution semantics. Several examples illustrate the efficiency of the controls that facilitate the execution of logic programs in a distributed manner and identify the class of applications that benefit from distributed platforms like PAN. George Xirogiannis, Ph.D.: He received his B.S. in Mathematics from the University of Ioannina, Greece in 1993, his M.S in Artificial Intelligence from the University of Bristol in 1994 and his Ph.D. in Computer Science from Heriot-Watt University, Edinburgh in 1998. His Ph.D. thesis concerns the automated execution of Prolog on distributed heterogeneous multi-processors. His research interests have progressed from knowledge-based systems to distributed logic programming and data mining. Currently, he is working as a senior IT consultant at Pricewaterhouse Coopers. He is also a Research Associate at the National Technical University of Athens, researching in knowledge and data mining. Hamish Taylor, Ph.D.: He is a lecturer in Computer Science in the Computing and Electrical Engineering Department of Heriot-Watt University in Edinburgh. He received M.A. and MLitt degrees in philosophy from Cambridge University and an M.S. and a Ph.D. degree in computer science from Heriot-Watt University, Scotland. Since 1985 he has worked on research projects concerned with implementing concurrent logic programming languages, developing formal models for automated reasoning, performance modelling parallel relational database systems, and visualisizing resources in shared web caches. His current research interests are in applications of collaborative virtual environments, parallel logic programming and networked computing technologies.     

Detecting causal relationships in distributed computations: In search of the holy grail

Summary The paper shows that characterizing the causal relationship between significant events is an important but non-trivial aspect for understanding the behavior of distributed programs. An introduction to the notion of causality and its relation to logical time is given; some fundamental results concerning the characterization of causality are presented. Recent work on the detection of causal relationships in distributed computations is surveyed. The issue of observing distributed computations in a causally consistent way and the basic problems of detecting global predicates are discussed. To illustrate the major difficulties, some typical monitoring and debugging approaches are assessed, and it is demonstrated how their feasibility is severely limited by the fundamental problem to master the complexity of causal relationships. Reinhard Schwarz received a diploma in computer science from the University of Kaiserslautern, Germany, in 1990. Since then, he is working as a research assistant at the computer science department. His research interests include debugging and monitoring of distributed systems, runtime support for object-oriented distributed programming, and distributed algorithms. Friedemann Mattern received the diploma in computer science from Bonn University, Germany, and the Ph.D. degree from the University of Kaiserslautern, Germany, in 1983 and 1989, respectively. Since 1991 he is a professor of computer science at the University of Saarland in Saarbrücken, Germany. His current research interests include programming of distributed systems, distributed applications, and distributed algorithms.The work presented in this paper was carried out as part of the PARAWAN project supported by the Bundesministerium für Forschung und Technologie (BMFT)     

Reliable broadcasts and communication models: tradeoffs and lower bounds

Reliable Broadcast is a mechanism by which a processor in a distributed system disseminates a value to all other processors in the presence of both communication and processor failures. Protocols to achieve Reliable Broadcast are at the heart of most fault-tolerant applications. We characterize the execution time of Reliable Broadcast protocols as a function of the communication model. This model includes familiar communication structures such as fully-connected point-to-point graphs, linear chains, rings, broadcast networks (such as Ethernet) and buses. We derive a parameterized protocol that implements Reliable Broadcast for any member within this class. We obtain lower bound results that show the optimality of our protocols. The lower bound results identify a time complexity gap between systems where processors may only fail to send messages, and systems where processors may fail both to send and to receive messages. The tradeoffs that our results reveal between performance, resiliency and network cost offer many new alternatives previously not considered in designing fault-tolerant systems. Özalp Babaoglu is Associate Professor in the Department of Computer Science at Cornell University, Ithaca, New York. His research interests include distributed systems, fault tolerance, performance evaluation and modeling. He received a BS in electrical engineering from George Washington University, Washington, D.C. in 1976. From the University of California, Berkeley, he received a MS in 1977 and a PhD in 1981, both in computer science. While at Berkeley, he designed and implemented the virtual memory extensions to VAX Unix that came to be known as 3. Obsd. Pat Stephenson is a Doctoral Candidate in the Computer Science Department at Cornell University, Ithaca, New York. His research interests include distributed systems and fault tolerance. In 1983, he received a B.A. (Mod.) in computer science from Trinity College, Dublin, Ireland. He received his MS in computer science from Cornell in 1986. He is currently working on new tradeoffs in the design of fault-tolerant algorithms. Rogério Drummond is Assistant Professor in the Computer Science Department at the Universidade Estadual de Campinas (UNICAMP), São Paulo, Brazil. His interests include distributed computing, fault tolerance and operating systems. He received a BS and a MS in computer science from the Universidade Estadual de Campinas in 1978 and 1980, respectively. In 1986 he received a PhD in computer science from Cornell University. He is currently working on integrated environments for the development of software and hardware.Partial support for this work was provided by the National Science Foundation under Grants DCR-86-01864 and MCS-82-10356 and AT&T under a Foundation GrantSupported partially by the Defense Advanced Research Projects Agency (DoD) under ARPA order 5378, Contract MDA 903-85-C-0124, and partially by an IBM graduate fellowship. The views, opinions and findings contained in this report are solely those of the authors and should not be construed as an official Department of Defense position, policy, or decisionSupported partially by the CAPES and CNPq agencies of the Ministry of Education of Brazil     

Efficient mining of association rules by reducing the number of passes over the database

This paper introduces a new algorithm of mining association rules.The algorithm RP counts the itemsets with different sizes in the same pass of scanning over the database by dividing the database into m partitions.The total number of pa sses over the database is only(k 2m-2)/m,where k is the longest size in the itemsets.It is much less than k .     

A formal approach to protocol performance testing

This paper proposes a formal approach to protocol performance testing based on the extended concurrent TTCN,To meet the needs of protocol performance testing,concurrent TTCN is extended,and the extended concurrent TTCN‘s operational semantics is defined in terms of Input-Output Labeled Transition System.An architecture design of protocol performance test system is described,and an example of test cases and its test result are given.     

Fast multicast on multistage interconnection networks using multi-head worms

1IntroductionMulticastcommunication,whichreferstothedeliveryofamessagefromasinglesourcenodetoanumberofdestinationnodes,isfrequentlyusedindistributed-memoryparallelcomputersystemsandnetworks[1].Efficientimplementationofmulticastcommunicationiscriticaltotheperformanceofmessage-basedscalableparallelcomputersandswitch-basedhighspeednetworks.Switch-basednetworksorindirectnetworks,basedonsomevariationsofmultistageiDterconnectionnetworks(MINs),haveemergedasapromisingnetworkajrchitectureforconstruct…     

Capabilities of outlier detection schemes in large datasets,framework and methodologies

Outlier detection is concerned with discovering exceptional behaviors of objects. Its theoretical principle and practical implementation lay a foundation for some important applications such as credit card fraud detection, discovering criminal behaviors in e-commerce, discovering computer intrusion, etc. In this paper, we first present a unified model for several existing outlier detection schemes, and propose a compatibility theory, which establishes a framework for describing the capabilities for various outlier formulation schemes in terms of matching users'intuitions. Under this framework, we show that the density-based scheme is more powerful than the distance-based scheme when a dataset contains patterns with diverse characteristics. The density-based scheme, however, is less effective when the patterns are of comparable densities with the outliers. We then introduce a connectivity-based scheme that improves the effectiveness of the density-based scheme when a pattern itself is of similar density as an outlier. We compare density-based and connectivity-based schemes in terms of their strengths and weaknesses, and demonstrate applications with different features where each of them is more effective than the other. Finally, connectivity-based and density-based schemes are comparatively evaluated on both real-life and synthetic datasets in terms of recall, precision, rank power and implementation-free metrics. Jian Tang received an MS degree from the University of Iowa in 1983, and PhD from the Pennsylvania State University in 1988, both from the Department of Computer Science. He joined the Department of Computer Science, Memorial University of Newfoundland, Canada, in 1988, where he is currently a professor. He has visited a number of research institutions to conduct researches ranging over a variety of topics relating to theories and practices for database management and systems. His current research interests include data mining, e-commerce, XML and bioinformatics. Zhixiang Chen is an associate professor in the Computer Science Department, University of Texas-Pan American. He received his PhD in computer science from Boston University in January 1996, BS and MS degrees in software engineering from Huazhong University of Science and Technology. He also studied at the University of Illinois at Chicago. He taught at Southwest State University from Fall 1995 to September 1997, and Huazhong University of Science and Technology from 1982 to 1990. His research interests include computational learning theory, algorithms and complexity, intelligent Web search, informational retrieval, and data mining. Ada Waichee Fu received her BSc degree in computer science in the Chinese University of Hong Kong in 1983, and both MSc and PhD degrees in computer science in Simon Fraser University of Canada in 1986, 1990, respectively; worked at Bell Northern Research in Ottawa, Canada, from 1989 to 1993 on a wide-area distributed database project; joined the Chinese University of Hong Kong in 1993. Her research interests are XML data, time series databases, data mining, content-based retrieval in multimedia databases, parallel, and distributed systems. David Wai-lok Cheung received the MSc and PhD degrees in computer science from Simon Fraser University, Canada, in 1985 and 1989, respectively. He also received the BSc degree in mathematics from the Chinese University of Hong Kong. From 1989 to 1993, he was a member of Scientific Staff at Bell Northern Research, Canada. Since 1994, he has been a faculty member of the Department of Computer Science in the University of Hong Kong. He is also the Director of the Center for E-Commerce Infrastructure Development. His research interests include data mining, data warehouse, XML technology for e-commerce and bioinformatics. Dr. Cheung was the Program Committee Chairman of the Fifth Pacific-Asia Conference on Knowledge Discovery and Data Mining (PAKDD 2001), Program Co-Chair of the Ninth Pacific-Asia Conference on Knowledge Discovery and Data Mining (PAKDD 2005). Dr. Cheung is a member of the ACM and the IEEE Computer Society.     

Scheduling algorithms based on weakly hard real-time constraints

The problem of scheduling weakly hard real-time tasks is addressed in this paper.The paper first analyzes the characters of μ-pattern and weakly hard real-time constraints,then,presents two scheduling algorithms,Meet Any Algorithm and Meet Row Algorithm,for weakly hard real-time systems.Different from traditional algorithms used to guarantee deadlines,MeetAny Algorithm and Meet Row Algorithm can guarantee both deadlines and constraints.Meet Any Algorithm and Meet Row Algorithm try to find out the probabilities of tasks breaking constraints and increase task‘s priority in advance,but not till the last moment.Simulation results show that these two algorithms are better than other scheduling algorithms dealing with constraints and can largely decrease worst-case computation time of real-time tasks.     

Necessary and sufficient conditions for broadcast consensus protocols

Summary We consider consensus protocols in asynchronous distributed systems that are based on broadcast communication. We show that a necessary and sufficient condition for the existence of a deterministic consensus protocol is delivery of each broadcast message to at least (n+k+1)/2 processes in ann-process system subject tok crash failures with either eventual fair broadcasting or eventual full broadcasting. The broadcast model captures the idea of a broadcast communication medium, such as the Ethernet, in which messages, if delivered, are delivered immediately and in order but not necessarily to all processes. Louise E. Moser received the Ph.D. degree in mathematics from the University of Wisconsin, Madison, in 1970. From 1970 to 1987 she was a professor of mathematics and computer science at California State University, Hayward. In 1987 she moved to the University of California, Santa Barbara, where is currently on the faculty of the Department of Electrical and Computer Engineering. Her current research interests include parallel and distributed systems, network architectures and communication protocols, and formal methods in software engineering. P.M. Melliar-Smith received the Ph.D. degree in computer science from the University of Cambridge, Cambridge, England, in 1987. He was a senior research scientist and program director at SRI International in Menlo Park (1976–1987), senior research associate at the University of Newcastle Upon Tyne (1973–1976), and principal designer for GEC Computers Ltd. in England (1964–1973). He is currently a professor in the Department of Electrical and Computer Engineering at the University of California, Santa Barbara. His research interests include fault-tolerant distributed systems, high-speed communication networks and protocols, and formal specification and verification. Vivek Agrawala received the B.Tech. degree in chemical engineering in 1984 and the M. Tech. degree in computer technology in 1986, both from the Indian Institute of Technology, Delhi, and a Ph.D. in computer science in 1991 from the University of California, Santa Barbara. Since then he has been a Research Scientist at Siemens Corporate Research, Princeton, New Jersey. His major research interests are distributed algorithms, software design methods, and distributed systems.This research was supported by the National Science Foundation, Grant Numbers CCR-8908515 and NCR-9016361. V. Agrawala's current address is Siemens Corporate Research, 755 College Road East, Princeton, NJ 08540, USA