Informatica Economica Vol. 14 No.
Issue Topic: Software Reliability
Issue Editor: Alexandru ISAIC-MANIU, PhD
Grigore C. Moisil Award 2010 5
Reliability and Its Quantitative Measures
Alexandru ISAIC-MANIU 7
In this article is made an opening for the software reliability issues, through wide-ranging statistical indicators, which are designed based on information collected from operating or testing (samples). It is developed the reliability issues also for the case of the main reliability laws (exponential, normal, Weibull), which validated for a particular system, allows the calculation of some reliability indicators with a higher degree of accuracy and trustworthiness
Keywords: Reliability Statistical Indicator, Cdf - Cumulative Distribution Function, Pdf - Probability Density Function, Reliability Function R(T), Weibull Law, Rayleigh Statistical Law, Sampling Plan, Average Lifetime, Testing Time, Reliability Sampling Plans, Statistical Models In Reliability
Estimation of the Reliability of Distributed Applications
Marian CRISTESCU, Laurentiu CIOVICA 19
In this paper the reliability is presented as an important feature for use in mission-critical distributed applications. Certain aspects of distributed systems make the requested level of reliability more difficult. An obvious benefit of distributed systems is that they serve the global business and social environment in which we live and work. Another benefit is that they can improve the quality of services, in terms of reliability, availability and performance, for the complex systems. The paper presents results of a study conducted by the students of Economic Informatics at the University "Lucian Blaga" Sibiu, over four months. The studied population was represented by several distributed applications made under the object oriented programming techniques. This study aimed to estimate the reliability of these applications using object-oriented design metrics validation techniques.
Keywords: Distributed Applications, Software Reliability, Software Metrics, Fault, Tolerance
Improving Software Performance in the Compute Unified Device Architecture
Alexandru PIRJAN 30
This paper analyzes several aspects regarding the improvement of software performance for applications written in the Compute Unified Device Architecture CUDA). We address an issue of great importance when programming a CUDA application: the Graphics Processing Unit’s (GPU’s) memory management through ranspose ernels. We also benchmark and evaluate the performance for progressively optimizing a transposing matrix application in CUDA. One particular interest was to research how well the optimization techniques, applied to software application written in CUDA, scale to the latest generation of general-purpose graphic processors units (GPGPU), like the Fermi architecture implemented in the GTX480 and the previous architecture implemented in GTX280. Lately, there has been a lot of interest in the literature for this type of optimization analysis, but none of the works so far (to our best knowledge) tried to validate if the optimizations can apply to a GPU from the latest Fermi architecture and how well does the Fermi architecture scale to these software performance improving techniques.
Keywords: Compute Unified Device Architecture, Fermi Architecture, Naive Transpose, Coalesced Transpose, Shared Memory Copy, Loop in Kernel, Loop over Kernel
Software Reliability in Semantic Web Service Composition Applications
Liviu Adrian COTFAS, Andreea DIOSTEANU 48
Web Service Composition allows the development of easily reconfigurable applications that can be quickly adapted to business changes. Due to the shift in paradigm from traditional systems, new approaches are needed in order to evaluate the reliability of web service composition applications. In this paper we present an approach based on intelligent agents for semiautomatic composition as well as methods for assessing reliability. Abstract web services, corresponding to a group of services that accomplishes a specific functionality are used as a mean of assuring better system reliability. The model can be extended with other Quality of Services – QoS attributes.
Keywords: Software Reliability, Web Service Composition, Intelligent Agents
Integration of the Functional Testing with the General Theory of the Technical Diagnosis
Mihai POPESCU 57
The paper goal is to integrate the software reliability into the general theory of the reliability, this thing being a natural approach, perfectly justified by the core concepts governing the two areas.
Keywords: Reliability, Faults, Errors, Functional Testing, Technical Diagnosis, Entropy
Reliability and Security- Convergence or Divergence
Emil BURTESCU 68
Reliability, as every technical field, must adapt to the new demands imposed by reality. Started initially as a field designed to control and ensure the smooth functionality of an element or technical system, reliability has reached the stage where the discussion is about the reliability management, similar to the other top-level fields. Security has its own contribution to the reliability of a system; a reliable system is a system with reliable security. In order for a system to be reliable, that means clear and safe, all its components must be reliable. In the following pages we will talk about the two main facts - reliability and security - to determine both the convergence and the divergence points.
Keywords: Reliability, Security, Failure, Threat, Redundancy, Costs, Investment
Evolution of Decision Support Systems Research Field in Numbers
Ana-Maria SUDUC, Mihai BIZOI, Marius CIOCA, Florin Gheorghe FILIP 78
The scientific production in a certain field shows, in great extent, the research interests in that field. Decision Support Systems are a particular class of information systems which are gaining more popularity in various domains. In order to identify the evolution in time of the publications number, authors, subjects, publications in the Decision Support Systems (DSS) field, and therefore the scientific world interest for this field, in November 2010 there have been organized a series of queries on three major international scientific databases: ScienceDirect, IEEE Xplore Digital Library and ACM Digital Library. The results presented in this paper shows that, even the decision support systems research field started in 1960s, the interests for this type of systems grew exponentially with each year in the last decades.
Keywords: DSS, Numbers, Research, Materials
Exploring the Usability of Municipal Web Sites: A Comparison Based on Expert Evaluation Results from Four Case Studies
Costin PRIBEANU, Ruxandra-Dora MARINESCU, Dragos Daniel IORDACHE, Maria Gheorghe-MOISII 87
The usability of public administration web sites is a key quality attribute for the successful implementation of the Information Society. Formative usability evaluation aims at finding and reporting usability problems as early as possible in the development process. The objective of this paper is to present and comparatively analyze the results of an expert usability evaluation of 4 municipality web sites. In order to document usability problems an extended set of heuristics was used that is based on two sources: usability heuristics and ergonomic criteria. The explanatory power of heuristics was supplemented with a set of usability guidelines. The evaluation results revealed that a set of specific tasks with clearly defined goals helps to identify many severe usability problems that occur frequently in the municipality web sites. A typical issue for this category of web sites is the lack of information support for the user.
Keywords: Formative Usability Evaluation, User Testing, Expert Evaluation, Heuristic Evaluation, Ergonomic Criteria, Usability Problem, Municipal Web Sites
A General Approach of Quality Cost Management Suitable for Effective Implementation in Software Systems
Stelian BRAD 97
Investments in quality are best quantified by implementing and managing quality cost systems. A review of various opinions coming from practitioners and researchers about the existent quality cost models reveals a set of drawbacks (e.g. too theoretical and too close to ideal cases; too academic, with less practical impact; too much personalized to particular business processes, with difficulties in extrapolating to other cases; not comprising all dimensions of a business system). Using concepts and tools in quality management theory and practice and algorithms of innovative problem solving, this paper formulates a novel approach to improve practical usability, comprehensiveness, flexibility and customizability of a quality cost management system (QCMS) when implementing it in a specific software application. Conclusions arising from the implementation in real industrial cases are also highlighted.
Keywords: Quality Costs, Performance Planning and Monitoring, Quality Management, Quality Cost Software
The Development and the Evaluation of a System for Extracting Events from Web Pages
Mihai-Constantin AVORNICULUI, Silviu Claudiu POPA, Constantin AVORNICULUI 114
The centralization of a particular event is primarily useful for running news services. These services should provide updated information, if possible even in real time, on a specific type of event. These events and their extraction involved the automatic analysis of linguistic structure documents to determine the possible sequences in which these events occur in documents. This analysis will provide structured and semi-structured documents in which the unit events can be extracted automatically. In order to measure the quality of a system, a methodology will be introduced, which describes the stages and how the decomposition of a system for extracting events in components, quality attributes and properties will be defined for these components, and finally will be introduced metrics for evaluation.
Keywords: Event, Performance Metric, Event Extraction System
Cardiovascular Attributable Risk and Risk Factors Evaluations as a Matter of Statistics and Data Mining Confluences
Dan-Andrei SITAR-TAUT, Adela SITAR-TAUT 124
Cardiovascular diseases represent a severe threat for humanity, being the first cause of death and hospitalization in both genders. An impressive number of studies have been developed in order to identify a set of factors causing this kind of illness, but only few of them were able to pay significant resources in analyzing large population samples (tens of thousands) and for longer periods of time (decades). This paper’s objective is to continue the previous researches of the eProCord project and to validate with concrete data the theoretical model developed for the attributable risk (AR). It will consider the same risk factors for myocardial infarction identified by INTERHEART study and the same work hypothesis. We will also evaluate if a certain value of the AR is also confirmed by the invoked disease of the patient. Using statistical and data mining tools we will investigate the prediction potential of the chosen factors and the opportunity to extend them in order to capture any cardiovascular disease. The empirical tests rely for now on a sample of 236 patients.
Keywords: Cardiovascular Disease, Myocardial Infarction, Attributable Risk, Roc, Data Mining, Classification
Aspects of a Watermark Solution
Dominic BUCERZAN, Crina RATIU, Ioan DASCAL 132
Although watermarking is a relatively new technology, there are many ways of applying it on an electronic data set with the purpose of ensuring copyright integrity and authenticity of the electronic data. But, bearing in mind the evolution of information technology and of communication, a watermark may be the target of several attacks which aim at its robustness, its form and even at its removal. In order to reduce these threats, this paper proposes a solution - digital watermarking completed by a hash function which has an important role in the authenticity of the content of a message and in the security of the transmission of this message through computer networks which are the main support of collaborative systems.
Keywords: Digital Watermarking, Hash Functions, Digital Information Security, Collaborative Systems
The Design of a Distributed Database for Doctoral Studies Management
Enikö Elisabeta TOLEA, Aurelian Razvan COSTIN 139
This paper aims to create a system that manages doctoral school requirements. The management of doctoral school implies administration of information like PhD personal information, Supervisors, Teachers, and other information that may be useful. We will debate on distributed database term as the proposed database project will have the same structure for four universities. Each university will be able to work on this database by accessing its own set of data and properly using the information received. This project will track the creation of a database to manage all the information needed and provide answers using these data.
Keywords: Distributed Database, Fragmentation, Top-Down Design Process
The Evaluation of Ontology Matching versus Text
Andreea-Diana MIHIS 147
Lately, the ontologies have become more and more complex, and they are used in different domains. Some of the ontologies are domain independent; some are specific to a domain. In the case of text processing and information retrieval, it is important to identify the corresponding ontology to a specific text. If the ontology is of a great scale, only a part of it may be reflected in the natural language text. This article presents metrics which evaluate the degree in which an ontology matches a natural language text, from word counting metrics to text entailment based metrics.
Keywords: Ontology, Natural Language Processing, Metric
Overlapping Boundaries of the Project Time Management and Project Risk Management
Ioan Marius PODEAN, Dan BENTA, Cristian MIRCEAN 156
Based on utility function, milestones during project and/or the end of projects or programme may be categorized in what are called soft-deadline and hard-deadline. In contrast with the soft-end projects, the hard-end projects posses a decrease of utility function with a vertical asymptote character around the deadline for project completion. In extreme situations, the utility function itself may fall under zero (projects may generate losses to both constructor and customer). Existing risk analysis methodologies observe risks from monetary terms. The typical risks are correlated with an increase in final project costs. In order to estimate harddeadline milestones and/or end of projects or programme is critical to employ the time dimension rather than the typical cost-based risk analysis. Here, we comprehensively describe a structured methodology that focuses on minimizing and mitigating project specific delay risks. The method may supplement existing cost-based risk analysis in projects. We aim to elegantly combine moderation techniques to reveal the intrinsic risk of the projects. In addition to the technical risks, the moderation techniques are able to bring evidence of risks as the team efficacy, diverse un-correlations or miss-understanding about the roles of the team members in the team – most of the project soft risk. Described methodology encourages the common understanding of risks for participants, crystallizing the essence of what can go wrong in complex situations and where the opportunities can be unlocked.
Keywords: Project Management, Risk Management, Time Management, Deadline, Delays
Matchmaking Framework for B2B E-Marketplaces
Fekete ZOLTÁN ALPÁR 164
In the recent years trading on the Internet become more popular. Online businesses gradually replace more and more from the conventional business. Much commercial information is exchanged on the internet, especially using the e-marketplaces. The demand and supply matching process becomes complex and difficult on last twenty years since the e-marketplaces play an important role in business management. Companies can achieve significant cost reduction by using e-marketplaces in their trade activities and by using matchmaking systems on finding the corresponding supply for their demand and vice versa. In the literature were proposed many approaches for matchmaking. In this paper we present a conceptual framework of matchmaking in B2B e-marketplaces environment.
Keywords: B2B Electronic Marketplaces, Conceptual Framework, Matchmaking, Multi- Objective Genetic Algorithm, Pareto Optimal
Information Systems in University Learning
Gheorghe SABAU, Ion LUNGU, Razvan BOLOGA, Ana Ramona BOLOGA, Alexandra Maria Ioana FLOREA 171
The authors of this article are going to bring into light the significance, the place and the role of information systems in the university education process. At the same time they define the objectives and the target group of the subject named Economic Information Systems and state the competence gained by students by studying this subject. Special attention is given to the curriculum to be taught to students and to a suggestive enumeration of a series of economic applications that can be themes for laboratory practice and for students’ dissertation (graduation thesis).
Keywords: Information System, Academic Partnership, Curriculum, General Competence, Specific Competence, Open Systems
The Development of Citizen Oriented Informatics
Ion IVAN, Leonard SACUIU, Daniel MILODIN, Mihai GEORGESCU 183
We define the concept of citizen-oriented computer application. Quality characteristics are set for computer applications developed in the conditions of citizen-oriented computing and outline the development cycle for these applications. It defines the conditions of existence for citizen-oriented applications. Average and long-term strategies are elaborated.
Keywords: Distributed Applications, Metrics, Citizen-Orientation, Strategies
ERP inside Large Organizations
Constantin Daniel AVRAM 196
Many large companies in Romania are still functioning without an ERP system. Instead they are using traditional application systems built around the strong boundaries of specific functions: finance, selling, HR, production. An ERP will offer lots of advantages among which the integration of functionalities and support for top management decisions. Although the total cost of ownership is not small and there are some risks when implementing an ERP inside large and very large organizations, having such a system is mandatory. Choosing the right product and vendor and using a correct risk management strategy, will ensure a successful implementation.
Keywords: Enterprise Functions, ERP Functionalities, Process Lines and Solutions, Cost Implementation, Total Cost of Ownership, Risk Management, Active Global Support, ERP Advantages, Success Factors, Return of Investment
The Tenth International Conference on Informatics in Economy IE 2011 209
Publishing Guide for Authors 210
Inforec Association 213