Verification of clock synchronization algorithms: experiments on a combination of deductive tools

We report on an experiment in combining the theorem prover Isabelle with automatic first-order arithmetic provers to increase automation on the verification of distributed protocols. As a case study for the experiment we verify several averaging clock synchronization algorithms. We present a formalization of Schneider’s generalized clock synchronization protocol [Sch87] in Isabelle/HOL. Then, we verify that the convergence functions used in two clock synchronization algorithms, namely, the Interactive Convergence Algorithm (ICA) of Lamport and Melliar-Smith [LMS85] and the Fault-tolerant Midpoint algorithm of Lundelius–Lynch [LL84], satisfy Schneider’s general conditions for correctness. The proofs are completely formalized in Isabelle/HOL. We identify parts of the proofs which are not fully automatically proven by Isabelle built-in tactics and show that these proofs can be handled by automatic first-order provers with support for arithmetics.     

Effectiveness of new Multiple-PSO based Membrane Optimization Algorithms on CEC 2014 benchmarks and Iris classification

This paper proposes a new Multiple-PSO based Membrane Algorithm (M_PSO_MA), which is a one-layered parallel and distributed membrane structure with seven different membranes, i.e., a skin membrane containing six elementary membranes using update rules of different PSOs. The idea is inspired from Frankenstein’s PSO (Oca et al. in IEEE Trans Evol Comput 13:1120–1132, 2009) which shows that by integrating components in novel ways effective optimizers can be designed. M_PSO_MA, is designed using the variants of PSO as given in Oca et al. (2009), which although are not hybridized but are applied simultaneously on the same population set. Each elementary membrane sends the best solution and the corresponding particle to the skin membrane, where the best solution is determined among all the collected solutions, which happens to be the best solution of the complete swarm. This global best solution and the corresponding particle are then communicated to all other membranes by the skin membrane besides retaining a copy for itself. The proposed algorithm, M_PSO_MA provides good quality solutions, but may sometime require slightly additional computational time. Therefore, its modified variant namely, MM_PSO_MA is also presented with an objective to minimize the computational time. Both, the proposed variants are compared with the existing best membrane algorithm determined in Singh et al. (Appl Math Comput 246:546–560, 2014) on the basis of CEC-2014 benchmark optimization problem set. In the second part of our paper M_PSO_MA and MM_PSO_MA are applied to solve a real life problem of Iris classification and the results are compared with Mutated PSO, namely MO-MPSO (Wang et al. in Int J Innov Comput Inform Control 9:2963–2977, 2013). The extensive results prove the supremacy of M_PSO_MA over other PSO based Membrane Algorithms. It is concluded that the proposed algorithm can be effectively used for solving complex real life problems as well.     

基于逻辑方程求解的网络故障定位规则的验证与实现

随着互联网的普及与快速发展,网络服务质量成为了最受关注的问题之一.本文利用矩阵半张量积方法,研究互联网网络中的故障定位问题.首先,利用矩阵半张量积给出网络中路径的代数表示.其次,基于该代数表示,将故障定位问题对应的逻辑方程转化为等价的代数方程,通过分析代数方程的解,确定网络中发生故障的链接.最后,通过例子说明所得理论结果的有效性.     

Challenges of real-world reinforcement learning: definitions,benchmarks and analysis

Machine Learning - Reinforcement learning (RL) has proven its worth in a series of artificial domains, and is beginning to show some successes in real-world scenarios. However, much of the research...     

Verification of real-time systems with preemption: negative and positive results

The aim of this article is to explore the problem of verification of preemptible real-time systems, i.e. systems composed of tasks which can be suspended and resumed by an on-line scheduler. The first contribution of the article is to show that this problem is unfortunately undecidable. To overcome this negative result, we restrict the real-time tasks to be periodic and the implementation to be functionally deterministic, meaning that the preemptions do not affect the functional behaviour and preserve some temporal properties satisfied by the specification. We prove that the verification problem of functional determinism is decidable. This outlines a verification strategy: (1) prove that the scheduled real-time system is deterministic, (2) consider a deterministic non preemptible behaviour which is functionally equivalent to the executions and (3) verify the properties on this behaviour.     

The genesis distributed memory benchmarks. Part 2: COMMS1, TRANS1, FFT1 and QCD2 benchmarks on the suprenum and IPSC/860 computers

The Genesis benchmark suite has been assembled to evaluate the performance of distributed-memory MIMD systems. The problems selected all have a scientific origin (mostly from physics or theoretical chemistry), and range from synthetic code fragments designed to measure the basic hardware properties of the computer (especially communication and synchronisation overheads), through commonly used library subroutines, to full application codes. This is the second of a series of papers on the Genesis distributed-memory benchmarks, which were developed under the European ESPRIT research program. Results are presented for the SUPRENUM and iPSC/860 computers when running the following benchmarks: COMMS1 (communications), TRANS1 (matrix transpose), FFT1 (fast Fourier transform) and QCD2 (conjugate gradient kernel). The theoretical predictions are compared with, or fitted to, the measured results, and then used to predict (with due caution) how the performance might scale for larger problems and more processors than were actually available during the benchmarking.     

Distributed data mining on grids: services, tools, and applications

Data mining algorithms are widely used today for the analysis of large corporate and scientific datasets stored in databases and data archives. Industry, science, and commerce fields often need to analyze very large datasets maintained over geographically distributed sites by using the computational power of distributed and parallel systems. The grid can play a significant role in providing an effective computational support for distributed knowledge discovery applications. For the development of data mining applications on grids we designed a system called Knowledge Grid. This paper describes the Knowledge Grid framework and presents the toolset provided by the Knowledge Grid for implementing distributed knowledge discovery. The paper discusses how to design and implement data mining applications by using the Knowledge Grid tools starting from searching grid resources, composing software and data components, and executing the resulting data mining process on a grid. Some performance results are also discussed.     

Runtime translation of OCL-like statements on Simulink models: Expanding domains and optimising queries

Software and Systems Modeling - Open-source model management frameworks such as OCL and ATL tend to focus on manipulating models built atop the Eclipse Modelling Framework (EMF), a de facto...     

Third international symposium onnumerical methods in engineering science Paris,March 14–16, 1983 and First international colloquium on vector andparallel computing in scientific applications Paris,March 17–18, 1983

This paper deals with the optimum design under given loads, of discrete (truss-like) linearly hardening or non-hardening plastic structures, subject to limitations on displacements and deformations and to linear technological constraints. Basic assumptions are: (i) the “cost” function is linear in the design variables; (ii) no local unstressing occurs under the given proportional loading, so that holonomic plastic laws can be adopted. Both elastic-plastic and rigid-hardening models are considered. A typical mathematical feature of the optimization problem is a (nonlinear, nonconvex) complementarity constraint.For situations where the local resistances, assumed to be design variables, do not affect the local stiffness, a branch-and-bound method is proposed and an alternative quadratic programming approach is envisaged. For situations where local strength and stiffness are coupled, a method is developed consisting basically of iterative applications of the procedure devised for uncoupled cases.The computational efficiency of the solution methods proposed is examined by means of numerical tests.     

Tutorial on ontological engineering Part 2: Ontology development,tools and languages

Practical aspects of ontological engineering are discussed in this part. First topic is the methodology of ontology development. Next, ontology representation languages and support tools are discussed as well as ontology alignment and merging which are becoming practically important to cope with distributed development of ontologies. We next discuss several ontologies developed thus far including large-scale knowledge bases such as Cyc, practical domain ontologies such as Enterprise ontology and gene ontology and generic ontologies such as PSL: Process Specification Language and SUO: Standard Upper Ontology. The first topic of ontology applications is the semantic web in which semantic interoperability, metadata and web service ontology are described. e-Learning is also a good application area of ontology in which LOM: Learning Object Metadata and ontology-aware authoring systems are discussed followed by conclusion. Riichiro Mizoguchi, Ph.D.: He is Professor of the Department of Knowledge Systems, the Institute of Scientific and Industrial Research, Osaka University. He received his B.S., M.S., and Ph.D. degrees from Osaka University in 1972, 1974 and 1977 respectively. From 1978 to 1986 he was research associate in the Institute of Scientific and Industrial Research, Osaka University. From 1986 to 1989 he was Associate Professor there. His research interests include Non-parametric data analyses, Knowledge-based systems, Ontological engineering and Intelligent learning support systems. He is a member of the Japanese Society for Artificial Intelligence, the Institute of Electronics, Information and Communica-tion Engineers, the Information Processing Society of Japan, the Japanese Society for Information and Systems in Education, Intl. AI in Education (IAIED) Soc., AAAI, IEEE and APC of AACE. Currently, he is President of IAIED Soc. and APC of AACE. He received honorable mention for the Pattern Recognition Society Award, the Institute of Electronics, Information and Communication Engineers Award, 10th Anniversary Paper Award from the Japanese Society for Artificial Intelligence and Best paper Award of ICCE99 in 1985, 1988, 1996 and 1999, respectively. He can be reached at miz@ei.sanken.osaka-u.ac.jp     

Model learning: a survey of foundations,tools and applications

Software systems are present all around us and playing their vital roles in our daily life. The correct functioning of these systems is of prime concern. In addition to classical testing techniques, formal techniques like model checking are used to reinforce the quality and reliability of software systems. However, obtaining of behavior model, which is essential for model-based techniques, of unknown software systems is a challenging task. To mitigate this problem, an emerging black-box analysis technique, called Model Learning, can be applied. It complements existing model-based testing and verification approaches by providing behavior models of blackbox systems fully automatically. This paper surveys the model learning technique, which recently has attracted much attention from researchers, especially from the domains of testing and verification. First, we review the background and foundations of model learning, which form the basis of subsequent sections. Second, we present some well-known model learning tools and provide their merits and shortcomings in the form of a comparison table. Third, we describe the successful applications of model learning in multidisciplinary fields, current challenges along with possible future works, and concluding remarks.     

Program Verification: State of the Art, Problems, and Results. I

An analytical survey of modern verification methods for sequential functional, reactive, and distributed systems is presented. The emphasis is on methods based on properties of abstract interpretation, transition systems, and Petri nets.