Computerized Accounting Systems: Measuring Structural Characteristics

This study aimed to develop a standard measurement tool for the effective assessment of computerized accounting systems (CAS) quality and effectiveness based on systems theory, in terms of their structural characteristics or functional components. The researcher identified five structural characteristics (components or subsystems) of CAS, namely internal controls, automated data-processing, relational database, automated reporting, and enhancing technologies components. The operationalization of these structural characteristics resulted in a 25-item index that forms the measurement tool developed. The 25-item index was constructed based on the review of prior literature to ensure content validity. The CAS measurement tool was administered to 384 active members of the Institute of Chartered Accountants of Nigeria (ICAN) through an online survey, and 234 useful responses were collected and analyzed to test the validity and reliability of the measurement tool. The researcher assessed the construct validity of the CAS measurement developed using the exploratory factor analysis, and the internal and external reliability using the Cronbach’s alpha test of consistency and test-retest statistics, respectively. The results of the study suggest that the CAS measurement tool developed has strong content and construct validity as well as high internal and external reliability. It is, therefore, believed that the tool would yield valid and reliable results when employed in the assessment of computerized accounting systems. The study is significant as it introduces a new approach to assessing the quality of accounting information systems in terms of their structural characteristics instead of qualitative characteristics such as perceived advantages and ease-of-use of the systems. Further research is suggested to confirm the validity and reliability of the CAS measurement tool presented in this study. Keywords: Accounting information systems, Automated data-processing, Automated reporting, Computerized accounting systems, Enhnacing technologies, Functional components, Internal controls, Relational database, Structural characteristics, Systems theory DOI: 10.7176/RJFA/11-16-05 Publication date:August 31st 202

Reasoning about the safety of information: from logical formalization to operational definition

We assume that safety of information stored in a database depends on the reliability of the agents who have performed the insertions in the database. We present a logic S to represent information safety, and to derive answers to standard queries and to safety queries. The design of this logic is based on signaling act theory. Two strong simplifications lead to a logic S" with two modalities to represent explicit beliefs and implicit beliefs. Then, we present an operational view of S" in terms of First Order Logic, with meta predicates, which is implemented by a Prolog meta program. lt is proved that answers derived in S" and computed by the meta program are identical. This property gives a clea.r meaning to computed answers. Content areas: Epistemological foundations, Theorem proving, Logic programming, Multi-agent systems

Simulation Assessment of the Operational Reliability of Mechanical Systems

Import 05/08/2014Disertační práce se zabývá simulačním odhadem provozní spolehlivosti strojních systémů. Jedná se o pravděpodobnostní způsob vyhodnocení provozní bezpečnosti strojů a jejich částí. Práce tvoří přehled o současném stavu řešené problematiky, tj. o deterministickém a pravděpodobnostním pojetí výpočtu. Další kapitoly práce se zabývají specifikací oboru spolehlivosti systémů, to znamená vymezení pojmů, definic a jednotlivých ukazatelů spolehlivosti včetně jejich vlastností. Důležitou kapitolou je teorie spolehlivosti různých struktur systémů, kde jsou znázorněny postupy vyhodnocení problematiky řazení jednotlivých prvků v systému. Dále je provedeno rozdělení metod a postupů analýz spolehlivosti včetně podrobného popisu zvolené metody SBRA (SBRA – Simulation-Based Reliability Assessment) a metody analýzy stromu poruchových stavů (FTA – Fault Tree Analysis). Všechny výše uvedené poznatky jsou aplikovány do analýzy spolehlivosti dvou vybraných strojních systémů, kterými jsou výsuvný kloubový hřídel s kluzným uložením a pravděpodobnostní kontrola upnutí hoblovacího nože u stolní hoblovky na dřevo. Velká pozornost je v této práci věnována simulačnímu odhadu provozní spolehlivosti jednotlivých prvků a jejich vliv na systém jako celek z hlediska různých typů zatížení z vlastní vytvořené databáze náhodných veličin, četností prvků apod. Simulační výsledky jsou porovnávány s deterministickým způsobem hodnocení provozní bezpečnosti a životnosti těchto systémů.The dissertation deals with simulating estimation of operating reliability of mechanical systems. It is concentrated on probability assessment of mechanical systems operating safety. In the introduction, the actual state of art such as deterministic and probability calculations are presented. The further chapters specify details in the field of systems reliability, the definitions, terms and reliability parameters are determined. The important chapter is the theory of system reliability where are presented assessment procedures of element position in the system. Beside it, there are specified methods and reliability analysis including details of SBRA – Simulation-Based Reliability Assessment and FTA – Fault Tree Analysis. The knowledge mentioned above is applied into a reliability analysis of two chosen mechanical systems – telescopic articular shaft with sliding embedding and probability check of planning knife fixation at planning table for wood. The main aim of the dissertation is simulating estimation of operating reliability of elements in the system in the view of variable load for created database of random variable, frequency. The acquired information is compared by deterministic assessment of operating safety and lifetime of the systems.Prezenční347 - Katedra částí a mechanismů strojůvyhově

The ACS LCID project IV: detection of the RGB bump in isolated galaxies of the Local Group

We report the detection and analysis of the red giant branch luminosity function bump in a sample of isolated dwarf galaxies in the Local Group. We have designed a new analysis approach comparing the observed color-magnitude diagrams with theoretical best-fit color-magnitude diagrams derived from precise estimates of the star formation histories of each galaxy. This analysis is based on studying the difference between the V-magnitude of the RGB bump and the horizontal branch at the level of the RR Lyrae instability strip (Delta_vhbb) and we discuss here a technique for reliably measuring this quantity in complex stellar systems. By using this approach, we find that the difference between the observed and predicted values of Delta_vhbb is +0.13 +/- 0.14 mag. This is smaller, by about a factor of two, than the well-known discrepancy between theory and observation at low metallicity commonly derived for Galactic globular clusters. This result is confirmed by a comparison between the adopted theoretical framework and empirical estimates of the Delta_vhbb parameter for both a large database of Galactic globular clusters and for four other dSph galaxies for which this estimate is available in the literature. We also investigate the strength of the red giant branch bump feature (R_bump), and find very good agreement between the observed and theoretically predicted R_bump values. This agreement supports the reliability of the evolutionary lifetimes predicted by theoretical models of the evolution of low-mass stars.Comment: Accepted for publication on Ap

The Application of the Hermeneutic Process to Qualitative Safety Data: A Case Study using Data from the CIRAS project

This article describes the new qualitative methodology developed for use in CIRAS (Confidential Incident Reporting and Analysis System), the confidential database set up for the UK railways by the University of Strathclyde. CIRAS is a project in which qualitative safety data are disidentified and then stored and analysed in a central database. Due to the confidential nature of the data provided, conventional (positivist) methods of checking their accuracy are not applicable; therefore a new methodology was developed - the Applied Hermeneutic Methodology (AHM). Based on Paul Ricoeur's `hermeneutic arc', this methodology uses appropriate computer software to provide a method of analysis that can be shown to be reliable (in the sense that consensus in interpretations between different interpreters can be demonstrated). Moreover, given that the classifiers of the textual elements can be represented in numeric form, AHM crosses the `qualitative-quantitative divide'. It is suggested that this methodology is more rigorous and philosophically coherent than existing methodologies and that it has implications for all areas of the social sciences where qualitative texts are analysed

Reliability modeling of a 1-out-of-2 system: Research with diverse Off-the-shelf SQL database servers

Fault tolerance via design diversity is often the only viable way of achieving sufficient dependability levels when using off-the-shelf components. We have reported previously on studies with bug reports of four open-source and commercial off-the-shelf database servers and later release of two of them. The results were very promising for designers of fault-tolerant solutions that wish to employ diverse servers: very few bugs caused failures in more than one server and none caused failure in more than two. In this paper we offer details of two approaches we have studied to construct reliability growth models for a 1-out-of-2 fault-tolerant server which utilize the bug reports. The models presented are of practical significance to system designers wishing to employ diversity with off-the-shelf components since often the bug reports are the only direct dependability evidence available to them