Nauki Techniczne

Theoretical and Applied Informatics

Zawartość

Theoretical and Applied Informatics | 2011 | No 1 |

Abstrakt

The main idea of all Active Queue Management algorithms, is to notify the TCP sender about incoming congestion by dropping packets, to prevent from the buffer overflow, and its negative consequences. However, most AQM algorithms proposed so far, neglect the impact of the high speed and long delay links. As a result, the algorithms’ efficiency, in terms of throughput and/or queue stability, is usually significantly decreased. The contribution of this paper is twofold. First of all, the performance of the well known AQM algorithms in high speed and long delay scenarios is evaluated and compared. Secondly, a new AQM algorithm is proposed, to improve the throughput in the large delay scenarios and to exclude the usage of random number generator.
Przejdź do artykułu

Abstrakt

Virtual machine described in the paper is a runtime program for controllers in small distributed systems. The machine executes intermediate universal code similar to an assembler, compiled in CPDev engineering environment from source programs written in control languages of IEC 61131-3 standard. The machine is implemented as a C program, so it can run on different target platforms. Data formats and commands of the machine code are presented, together with the machine’s Petri-net model, C implementation involving universal and platform-dependent modules, target hardware interface, input/output programming mechanisms, and practical applications.
Przejdź do artykułu

Abstrakt

The material presents a real problem inherent in the management of computer systems, namely that of finding the appropriate system settings and thus being able to achieve the expected perfor- mance. The material also presents a prototype which aims to adapt the system in such a way as to achieve the objective, defined as the application efficiency. The prototype uses a resource-oriented mechanism that is built into the OS Workload Manager and is focused on a proposed goal-oriented subsystem based on fuzzy logic, managing resources to make the best use of them, and pursuing translation to the use of system resources, including nondeterministic technology-related factors such as duration of allocation and release of the resources, sharing the resources with the uncapped mode, and the errors of performance measurement.
Przejdź do artykułu

Abstrakt

An accurate use of the ability to steer computer efficiency is essential from the database point of view. Effective resource allocation is dependent on the performance indicators gathered from running systems. There must be an appropriate balance between accurate measurements, performance indicators and speed of the reallocation algorithms of the computing resources. The extended measurement of efficiency which the authors propose for applications is: the average number of queries within a time unit for particular groups of users. This paper presents an analysis of using the Workload Manager utility in the AIX 5L operating system to improve the efficiency of applications in the MySQL database environment, and an analysis of methods which allows the use of Workload Manager for steering efficiency dynamically.
Przejdź do artykułu

Abstrakt

In this article, authors analyze methods of the analysis of data integrity, security and availability loss results for business processes. Assessing those results, one can judge the importance of a process in organization; thus, determine which business process requires more attention. The importance of those processes can be determined with Business Impact Analysis (BIA). In article, first phase of BIA is presented – in specific, a construction of Business Impact Category Tables, Loss Levels and process weight calculation methods. A variety of weight calculating methods is presented. Authors also present their proposed method – square sum percentage – as a solution eliminating problems of other weight calculation methods in business impact analysis.
Przejdź do artykułu

Redakcja

Editor-in-Chief: Prof. dr hab. inż. Jerzy Klamka

Managing Editor:
dr hab. Jarosław Miszczak

Kontakt

Theoretical and Applied Informatics Institute of Theoretical and Applied Informatics Polish Academy of Sciences Bałtycka 5, 44-100 Gliwice, Poland https://taai.iitis.pl/ Editorial Office Secretary dr hab. Jarosław Miszczak e-mail: taai.editor@iitis.pl

Instrukcje dla autorów

Submissions of a manuscript for publication in TaAI implies that the paper was not previously published (with possible exceptions of selected conference and invited papers) and is not being submitted for publication elsewhere; that permission for publication, if needed, has been granted by appropriate sources; and the first author ensures that other authors have approved the paper for publication.

Manuscripts (in 2 paper copies and electronic copy) should be sent directly to the Editorial Office. All further correspondence, proofs and offprints will be sent to the first author, unless indicated otherwise by the authors.

All papers will be evaluated by one of the Editors and will be reviewed.

Suitability for publication will be judged on the basis of relevance of the paper contents to the overall TaAI aims and scope, its originality, technical quality, importance and readability.

The language of the journal is English (with possible exceptions). The text should be formatted, and appropriate templates (DOC or TeX format) are available at: taai.iitis.gliwice.pl

Author will receive 10 offprints of published paper without charge.

Authors can receive their paper for a galley proof. Extensive changes of the text in galley proofs are unacceptable; in exceptional cases a note added in a proof can be included at the end of paper. If the proofs are not returned promptly, the article will be proof-read against the manuscript by the publisher and printed without author's corrections.

Editorial Office right is to skip galley proof stage in the process of publication.

Ta strona wykorzystuje pliki 'cookies'. Więcej informacji