Acta Informatica Pragensia, 2013 (vol. 2), issue 2

Novel methods of utilizing Jitter for Network Congestion Control

Ivan Klimek, Marek Čajkovský, František Jakab

Acta Informatica Pragensia 2013, 2(2), 1-24 | DOI: 10.18267/j.aip.204890  

This paper proposes a novel paradigm for network congestion control. Instead of perpetual conflict as in TCP, a proof-of-concept first-ever protocol enabling inter-flow communication without infrastructure support thru a side channel constructed on generic FIFO queue behaviour is presented. This enables independent flows passing thru the same bottleneck queue to communicate and achieve fair capacity sharing and a stable equilibrium state in a rapid fashion.

Flexible data queries

Miroslav Hudec

Acta Informatica Pragensia 2013, 2(2), 25-38 | DOI: 10.18267/j.aip.216806  

The Structured Query Language (SQL) has been established as a standard for querying relational databases. However, users face the problem how to define their requirements for data by the exact query conditions. This work examines advantages of fuzzy queries, which provide a better representation of the user requirements by expressing imprecise conditions through linguistic terms. Further, the paper discusses solving empty and overabundant answer problems, revealing similarities in database entities and applying preferences in query conditions. Finally, paper discusses practical realisations of fuzzy queries.

A Review on Macroscopic Pedestrian Flow Modelling

Anna Kormanová

Acta Informatica Pragensia 2013, 2(2), 39-50 | DOI: 10.18267/j.aip.226530  

This paper reviews several various approaches to macroscopic pedestrian modelling. It describes hydrodynamic models based on similarity of pedestrian flow with fluids and gases; first-order flow models that use fundamental diagrams and conservation equation; and a model similar to LWR vehicular traffic model, which allows non-classical shocks. At the end of the paper there is stated a comparison of described models, intended to find appropriate macroscopic model to eventually be a part of a hybrid model. The future work of the author is outlined.

Subgraph Colouring Technique for Computer with Data Driven Computation Model

Liberios Vokorokos, Branislav Madoš, Norbert Ádám, Marek Čajkovský

Acta Informatica Pragensia 2013, 2(2), 51-58 | DOI: 10.18267/j.aip.233355  

Paper deals with the data driven computation control paradigm, which is alternative to the mainstream control flow model of program execution control. In the second part of the paper we are introducing computer architecture that is proposed at the Department of Computers and Informatics, Faculty of Electrical Engineering and Informatics, Technical University of Košice, according to the data driven computation control model with use of tile computing principles. In the final part of the paper, subgraph colouring technique that is unique characteristic of proposed computer architecture is described.

Framework for utilizing computational devices within simulation

Miroslav Mintál

Acta Informatica Pragensia 2013, 2(2), 59-67 | DOI: 10.18267/j.aip.243492  

Nowadays there exist several frameworks to utilize a computation power of graphics cards and other computational devices such as FPGA, ARM and multi-core processors. The best known are either low-level and need a lot of controlling code or are bounded only to special graphic cards. Furthermore there exist more specialized frameworks, mainly aimed to the mathematic field. Described framework is adjusted to use in a multi-agent simulations. Here it provides an option to accelerate computations when preparing simulation and mainly to accelerate a computation of simulation itself.

TOGAF usage in outsourcing of software development

Aziz Ahmad Rais, Rudolf Pecinovsky

Acta Informatica Pragensia 2013, 2(2), 68-76 | DOI: 10.18267/j.aip.255990  

TOGAF is an Enterprise Architecture framework that provides a method for developing Enterprise Architecture called architecture development method (ADM). The purpose of this paper is whether TOGAF ADM can be used for developing software application architecture. Because the software application architecture is one of the disciplines in application development life cycle, it is important to find out how the enterprise architecture development method can support the application architecture development. Having an open standard that can be used in the application architecture development could help in outsourcing of software development. If ADM could...

Mikroprogram pre riadenie procesu spájania operandov v architektúre DF KPI

Microprogram for operand matching in DF KPI architecture

Norbert Ádám

Acta Informatica Pragensia 2013, 2(2), 77-96 | DOI: 10.18267/j.aip.262894  

The architecture described in this article is based on the data-flow computation model, in which computation is driven by processing a flow of data. The basic element of the data-flow architecture is the coordinating processor (CP), responsible for controlling and organizing the execution of instructions. As to its structure, the CP is designed as a dynamic, multi-functional system. When executing the operations, the CP may acquire various states, therefore it is a dynamic pipelining system. The transitions and the order of the states between two transitions depend on the type of the operator processed at the time of interpreting the flow of operands....

Inovativní přístup k rozvoji Informačního managementu magisterského oboru studia na VŠE v Praze

An innovative approach to the development of the master study of the Information management at the University of Economics in Prague

Vlasta Střížová, Zdeněk Smutný

Acta Informatica Pragensia 2013, 2(2), 97-111 | DOI: 10.18267/j.aip.274081  

Increasing globalization, competition, but also the economic situation in our country and in the world, a powerful development of technology and rapid changes in organizations are just a few of the important factors why an innovative ideas and approaches become increasingly important for the universities. The aim of this paper is to contribute to the innovation of the master study of the Information management (field of study) in the University of Economics in Prague. The presentation is based on the theoretical approaches to the concept of the information management and at the same time it maps and compares the current situation and approaches of...

Systémová dynamika: disciplína pro zkoumání komplexních měkkých systémů

System dynamics: discipline for studying complex soft systems

Stanislava Mildeová

Acta Informatica Pragensia 2013, 2(2), 112-121 | DOI: 10.18267/j.aip.286514  

The objective of the paper is to introduce system dynamics that helps in solving complex problems, and aids our better understanding of surrounding systems. System dynamics is especially useful for analysing systems with a high amount of detail and dynamic complexity, such as any complex social systems. An economic system is a typical example of a complex social system. The author, with an emphasis on the characteristics of economic-social systems, illustrates the basic logic of system dynamics and its relation to informatics.

Dynamika sociálně-ekonomických procesů

Dynamics of socio-economic processes

Ingeborg Němcová

Acta Informatica Pragensia 2013, 2(2), 122-124 | DOI: 10.18267/j.aip.292488  

A review of a monograph by Ignác Prno: "Dynamika sociálno-ekonomických procesov: simulovanie dynamiky v sociálno-ekonomických systémech" (Dynamics of social and economic processes: simulations of dynamics in social and economic systems) which was published by Slovak Academy of Science in Bratislava in 2012. The book presents a in a systematically organized comprehensive knowledge and tools to managers and to everybody with an interest in modelling of dynamic soft systems. The CD with software which is accompanying the book allows readers to get the knowledge in an interactive way.

(In)formování sociálních systémů

(In)formation of social systems

Miloš Vítek

Acta Informatica Pragensia 2013, 2(2), 125-142 | DOI: 10.18267/j.aip.303425  

The original orientation of Systems Engineering on hard technological systems is still prevailing. But an advanced respect to a design and redesign of sociocultural systems is necessary. The notion of the social system is well known since the 20th century from excellent works of Parsons, Luhmann, Habermas, Bourdieu, Foucault, etc. The contribution selects some fundamental ideas on social systems from philosophy and sociology of modernity for the purposes of an up-to-date Systems Engineering and it shows their incorporation in significant system studies on design of sociocultural systems in the Czech Republic. This is thesis of the 45th Conference on...