Service-Oriented Computing for intelligent train maintenance

The purpose of this work is to apply the servicization of enterprise information systems in maintenance, particularly in the management of the maintenance process of the component parts of trains. Service Oriented Architecture (SOA) is an architectural approach that permits servicization since it provides a flexible set of design principles used during the modeling practices (abstraction and realization). With a view to supporting the model-driven engineering of software systems, Mode Driven Architecture (MDA) is a design approach delivering a set of guidelines for the configuring of specifications in systems development. Therefore, the combination of these two approaches can be fruitful to address the challenging issues the enterprise information system is facing today. Our study is based on a methodological approach using the MDA models for the automatic generation of web service. The case study concerns a Railways Maintenance Workshop (RMW) at Sidi Bel Abbes (Algeria). Finally, the information system for the management of maintenance of the component parts of passengers and baggage railcars, using the generated solution, is realized and deployed. This software helps to have better management of the RMW by the effective planning of interventions, improve performance by increasing reliability, traceability, and availability of the equipment (parts).     

Distribution of residual autocorrelations for multiplicative seasonal ARMA models with uncorrelated but nonindependent error terms

In this paper, we consider portmanteau tests for testing the adequacy of multiplicative seasonal autoregressive moving‐average models under the assumption that the errors are uncorrelated but not necessarily independent. We relax the standard independence assumption on the error terms in order to extend the range of applications of the seasonal autoregressive moving‐average models. We study the asymptotic distributions of residual and normalized residual empirical autocovariances and autocorrelations under weak assumptions on noise. We establish the asymptotic behavior of the proposed statistics. A set of Monte Carlo experiments and an application to monthly mean total sunspot number are presented.     

Do National Cultures Matter for External Audits? Evidence from Eastern Europe and the Middle East

Journal of Business Ethics - This study aims to examine the relationship between national cultural dimensions and the probability of a firm being externally audited. It uses a large set of...     

Ex ante capital position,changes in the different components of regulatory capital and bank risk

We investigate the impact of changes in capital of European banks on their risk-taking behaviour from 1992 to 2006, a time period covering the Basel I capital requirements. We specifically focus on the initial level and type of regulatory capital banks hold. First, we assume that risk changes depend on banks’ ex ante regulatory capital position. Second, we consider the impact of an increase in each component of regulatory capital on banks’ risk changes. We find that, for highly capitalized, adequately capitalized and strongly undercapitalized banks, an increase in equity or in subordinated debt positively affects risk. Moderately undercapitalized banks tend to invest in less risky assets when their equity ratio increases but not when they improve their capital position by extending hybrid capital or subordinated debt. On the whole, our conclusions support the need to implement more explicit thresholds to classify European banks according to their capital ratios but also to clearly distinguish pure equity from hybrid and subordinated instruments.