Numer czasopisma
Computer Science
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ISSN: 1508-2806
e-ISSN:
Data wydania
2013
Rocznik
Vol. 14
Numer
No. 3
Prawa dostępu
Dostęp: otwarty dostęp
Uwagi:
Prawa: CC BY 4.0 
Uznanie autorstwa 4.0 Międzynarodowe (CC BY 4.0)
Strony
Opis
Rocznik czasopisma (rel.)
Rocznik czasopisma
Computer Science
Vol. 14 (2013)
Artykuły numeru (rel.)
Artykuł
Dostęp ograniczony
Portable userspace virtual filesystem switch
(2013) Faber, Łukasz; Boryczko, Krzysztof
Multiple different filesystems — including disk-based, network, distributed, abstract — are an integral part of every operating system. They are usually written as kernel modules and abstracted to the user via a virtual filesystem switch. In this paper, we analyze the feasibility of reimplementing the virtual filesystem switch as a userspace daemon and applicability of this approach in real-life usage. Such reimplementation will require a way to virtualize processes behavior related to filesystem operations. The problem is non-trivial, as we as-sume limited capabilities of the VFS switch implemented in userspace. We present a layered architecture comprising of a monitoring process, the VFS abstraction and real filesystem implementations. All working in userspace. Then, we evaluate this solution in four areas: portability, feasibility, usability, and performance. Our results demonstrate possible gains in the use of a userspace-based approach with monolithic kernels, but also underline problems that are encountered in this approach.
Artykuł
Dostęp ograniczony
Evolutionary multi-agent computing in inverse problem
(2013) Wróbel, Krzysztof; Torba, Paweł; Paszyński, Maciej; Byrski, Aleksander
This paper tackles the application of evolutionary multi-agent computing to solve inverse problems. High costs of fitness function call become a major difficulty when approaching these problems with population-based heuristics. However, evolutionary agent-based systems (EMAS) turn out to reduce the fitness function calls, which makes them a possible weapon of choice against them. This paper recalls the basics of EMAS and describes the considered problem (Step and Flash Imprint Lithography), and later, shows convincing results that EMAS is more effective than a classical evolutionary algorithm.
Artykuł
Dostęp ograniczony
Using shared memory as a cache in cellular automata water flow simulations on GPUs
(2013) Topa, Paweł; Młocek, Paweł
Graphics processors (GPU – Graphic Processor Units) recently have gained a lot of interest as an efficient platform for general-purpose computation. Cellular Automata approach which is inherently parallel gives the opportunity to implement high performance simulations. This paper presents how shared memory in GPU can be used to improve performance for Cellular Automata models. In our previous works, we proposed algorithms for Cellular Automata model that use only a GPU global memory. Using a profiling tool, we found bottlenecks in our approach. With this paper, we will introduce modifications that takes an advantage of fast shared memory. The modified algorithm is presented in details, and the results of profiling and performance test are demonstrated. Our unique achievement is comparing the efficiency of the same algorithm working with a global and shared memory.
Artykuł
Dostęp ograniczony
Car-finding system with couchdb-based sensor management platform
(2013) Nocuń, Łukasz; Nieć, Michał; Pikuła, Paweł; Mamla, Aleksander; Turek, Wojciech
The growing performance of low-cost mobile devices makes it possible to perform advanced processing on mobile sensors. This creates the need to building a management system for groups of sensors actively analyzing signals fromhardware devices. In this paper, an architecture of a CouchDB-Based Sensor Management Platform is presented and its application for the problem of finding stolen cars is shown. Detailed performance tests of the platform as well as its application are provided.
Artykuł
Dostęp ograniczony
Geolocalization of 19th-century villages and cities mentioned in geographical dictionary of the Kingdom of Poland
(2013) Jaśkiewicz, Grzegorz
This article presents a method of the rough estimation of geographical coordinates of villages and cities, which is described in the 19th-Century geographical encyclopedia entitled: “The Geographical Dictionary of the Polish Kingdom and Other Slavic Countries”[18]. Described are the algorithm function for estimating location, the tools used to acquire and process necessary information, and the context of this research.
Artykuł
Dostęp ograniczony
Comparison of two kinds of fuzzy arithmetic, LR and OFN, applied to fuzzy observation of the cofferdam water level
(2013) Czerniak, Jacek; Dobrosielski, Wojciech; Angryk, Rafał
This paper presents certain important aspect soft he fuzzy logic extension, one of whichis OFN. It includes basic definition soft hat discipline. It also compares fuzzy logic arithmetic with the arithmetic of ordered fuzzy numbers in L-R notation. Computational experiments were based on fuzzy observation of the impounding basin. The results of the study show that there is a connection between the order of OFN number and trend of changes in the environment. The experiment was carried out using computer soft ware developed specially for that purpose.When comparing the arithmetic of fuzzy numbers in L-R notation with the arithmetic of ordered fuzzy number son the ground soft he experiment, it has been concluded that with fuzzy numbers it ispossible to expand the scope of solutions in comparison to fuzzy numbers inclassic form. The symbol of OFNflexibility is the possibility to determine the number that always satisfies the equation A+X=C, regardles soft hevalue of arguments. Operations performed on OFN are less complicated, as the yare performed in the same way regard less the sign of the input data and the irresultsare more accuratein the majority of cases.The promising feature of ordered fuzzy numbers is their lack of rapidly growing fuzziness. Authors expect to see implication of that fact in practice in the near future.
Artykuł
Dostęp ograniczony
FPGA-based multi-core processor
(2013) Wójcik, Wojciech; Długopolski, Jacek
The paper presents the results of investigations concerning the possibility of using programm able logic devices (FPGA) to build virtual multi-core processors dedicated specifically towards particular applications.The paper shows the designed architecture of a multi-core processor specialized to perform a particular task, and it discusses its computational efficiency depending on the number of cores used. An evaluation of the results is also discussed.
Artykuł
Dostęp ograniczony
Simple cyclic movements as a distinct autism feature – computational approach
(2013) Dobosz, Krzysztof; Mikołajewski, Dariusz; Wójcik, Grzegorz Marcin; Duch, Włodzisław
A diversity of symptoms in autism dictates a broad definition of AutismSpec-trum of Disorders (ASD). Each year, the percentage of children diagnosed with ASD is growing. One common diagnostic feature in individuals with ASD is the tendency to exhibit atypical simple cyclic movements.The motor brain activity seems to generate a periodic attractor state that is hard to escape. Despite numerous studies, scientists and clinicians do not know exactly if ASD is a result of a simple yet general mechanism or of a complex set of mechanisms (either on the neural, molecular and system levels). Simulations using the biologically- relevant neural network model presented here may help to reveal the simplest mechanisms that may be responsible for specific behavior. Abnormal neural fatigue mechanisms may be responsible for motor symptoms as well as many (or perhaps all) of the other symptoms observed in ASD.
Artykuł
Dostęp ograniczony
Tuning of agent-based computing
(2013) Byrski, Aleksander
In this paper, an Evolutionary Multi-agent system-based computing process is subjected to a detailed analysis of its parameters in order to establish a base for a better understanding of the meta-heuristics from the practitioner’s point of view. After reviewing the concepts of EMAS and its immunological variant, a series of experiments is shown, and results of the influence of the search outcomes by certain parameters is discussed.
Artykuł
Dostęp ograniczony
Modular fem framework “ModFEM” for generic scientific parallel simulations
(2013) Michalik, Kazimierz; Banaś, Krzysztof; Płaszewski, Przemysław; Cybułka, Paweł
We present the design for, and implementation of, aflexible and robust parallel modular finite element (FEM) framework called ModFEM. The designis based on reusable modules which use narrow and well-defined interfaces to cooperate. At the top of the architecture, there are problem - dependent modules. Problem - dependent modules can be additionally grouped together by“super-modules”. The structure allows for reusing the sequential code for parallel environments, and also supports solving multi-physics and multi-scale problems.