Fundamenta Informaticae - Volume 138, issue 4

Authors: Abbasian, Mohammad Amir | Nezamabadi-pour, Hossein | Amoozegar, Maryam

Article Type: Research Article

Abstract: Gravitational search algorithm(GSA) is a recent created metaheuristic optimization algorithm with good results in function optimization as well as real world optimization problems. Many real world problems involve multiple (often conflicting) objectives, which should be optimized simultaneously. Therefore, the aim of this paper is to propose a multi-objective version of GSA, namely clustering based archive multi-objective GSA (CA-MOGSA). Proposed method is created based on the Pareto principles. Selected non-dominated solutions are stored in an external archive. To control the size of archive, the solutions with less crowding distance are removed. These strategies guarantee the elitism and diversity as two important …features of multi-objective algorithms. The archive is clustered and a cluster is randomly selected for each agent to apply the gravitational force to attract it. The selection of the proper cluster is based on the distance between clusters representatives and population member (the agent). Therefore, suitable trade-off between exploration and exploitation is provided. The experimental results on eight standard benchmark functions reveal that CA-MOGSA is a well-organized multi-objective version of GSA. It is comparable with the state-of-the- art algorithms including non-dominated sorting genetic algorithm-II (NSGA-II), strength Pareto evolutionary algorithm (SPEA2) and better than multi-objective GSA (MOGSA), time-variant particle swarm optimization (TV-PSO), and non-dominated sorting GSA (NSGSA). Show more

Keywords: Multi objective optimization, gravitational search algorithm, Archive clustering, diversity preservation, elitism

DOI: 10.3233/FI-2015-1218

Citation: Fundamenta Informaticae, vol. 138, no. 4, pp. 387-409, 2015

Authors: Bergstra, J.A. | Middelburg, C.A.

Article Type: Research Article

Abstract: Every partial function from bit strings of a given length to bit strings of a possibly different given length can be computed by a finite instruction sequence that contains only instructions to set and get the content of Boolean registers, forward jump instructions, and a termination instruction. We look for an equivalence relation on instruction sequences of this kind that captures to a reasonable degree the intuitive notion that two instruction sequences express the same algorithm.

Keywords: structural algorithmic equivalence, structural computational equivalence, single-pass instruction sequence, bit string function

DOI: 10.3233/FI-2015-1219

Citation: Fundamenta Informaticae, vol. 138, no. 4, pp. 411-434, 2015

Authors: Chunlin, Li | LaYuan, Li

Article Type: Research Article

Abstract: In the paper, we consider the hybrid cloud model used for cloud bursting, when the computational capacity of the private cloud provider is insufficient to deal with the peak number of customers’ applications, the private cloud will rely on the resources leased from public cloud providers for the execution of private cloud applications. The paper proposes the model and algorithm of hybrid cloud scheduling optimization for cloud bursting. Public cloud providers and private cloud users communicate by the hybrid cloud marketplace. The hybrid cloud scheduling optimization is conducted at different levels. According to the model formulation and mathematic solutions of …hybrid cloud scheduling, hybrid cloud scheduling algorithms for cloud bursting are proposed, which includes the routines of public cloud optimization, private cloud application optimization and private cloud job optimization. In the simulations, compared with other related algorithm, our proposed hybrid cloud scheduling algorithms achieve the better performance. Show more

Keywords: hybrid cloud, cloud bursting, multicriteria optimization

DOI: 10.3233/FI-2015-1220

Citation: Fundamenta Informaticae, vol. 138, no. 4, pp. 435-455, 2015

Authors: Laskowski, Lukasz | Jelonkiewicz, Jerzy

Article Type: Research Article

Abstract: In the present paper we describe innovative architecture of artificial neural network based on Hopfield structure - Self Correcting Neural Network (SCNN). It is implementation similar to dual mode Hopfield-like network for solving stereo matching problem. Considered network consists of basic layer of neurons implemented as analogue Hopfield-like network and supervising layer. Thanks to the supervising layer, there is a possibility of modification of the connection weights between the neurons in the basic layer. This enables the improvement of the network performance (accuracy). Authors propose a depth map use for image segmentation and objects auto-selection. High enough accuracy of these …processes can be achieved when proposed network (SCNN) is applied. Similar idea can be applied also for images noise removal. In the present article we also describe in detail neurons dynamics in the basic and supervising layers of the SCNN. The network considered here was a subject of experimental tests using real stereo pictures as well as simulated stereo images. This enabled calculation of error and direct comparison with classic analogue Hopfield neural network. Show more

Keywords: Hopfield, self-correcting neural networks, stereovision, depth analysis, hybrid network, objects selection, segmentation

DOI: 10.3233/FI-2015-1221

Citation: Fundamenta Informaticae, vol. 138, no. 4, pp. 457-482, 2015

Authors: Moschoyiannis, Sotiris | Krause, Paul J.

Article Type: Research Article

Abstract: The concept of a digital ecosystem (DE) has been used to explore scenarios in which multiple online services and resources can be accessed by users without there being a single point of control, which can be used to effectively serialise their interactions. We argue in this paper that this weak coupling between services places additional demands on the modelling of compensation and recovery management in long-running transactions over traditional SOC related formalisms. We describe an adaptation of Shields’ vector languages , in that the synchronisation constraint is removed (no shared actions), as a formal semantics for a transaction in terms …of the common ordering constraints on the underlying interactions between its participants. The notation afforded by the so-called transaction languages captures the invocations on each participant service (online resource), and at each point during execution, across the whole transaction. Concurrency is modelled explicitly through a notion of independence, which is lifted onto tuples of sequences (one for each participant of the transaction) rather than individual sequences, as in Mazurkiewicz trace languages or events, as in the event structures model. Participating subcomponents execute concurrently and failure of one or more causes the recovery of the whole transaction. Compensations are triggered immediately upon failure and concurrent forward actions are compensated concurrently. We highlight the benefits of our true-concurrent approach in the context of DEs and outline connections of transaction languages to other partial order models. Further, we discuss how our approach supports forward recovery in that recovering the whole transaction is avoided wherever possible. Show more

Keywords: services, online resources, coordination, choreography, true concurrency, transactions, compensation semantics, transaction languages, equivalent execution histories, forward recovery

DOI: 10.3233/FI-2015-1222

Citation: Fundamenta Informaticae, vol. 138, no. 4, pp. 483-514, 2015

Article Type: Other

Citation: Fundamenta Informaticae, vol. 138, no. 4, pp. 515-516, 2015