The implementation of material requirements planning (MRP) systems in Egyptian manufacturing companies: an empirical study

The new world economic conditions and increasing global competition have changed the way in which manufacturing companies view production/operations management and their role in achieving greater productivity, lower costs, operational efficiency and better customer service. Several manufacturing planning and control systems have been developed in order to enable manufacturers to meet these new challenges. Material Requirements Planning System-MRP I and its extension Manufacturing Resources Planning System-MRP II, the much proclaimed systems, have gained wide acceptance from both academics and practitioners. The research presented here concentrates on the key issues of MRP practices and the effectiveness of MRP systems. Evidence from the literature shows that over 60 percent of MRP I/MRP II users have failed to achieve the expected benefits. Also, a review of the literature reveals that very little work has been done to provide mathematical models to relate these benefits to their determinants. Furthermore, it reveals that much was written about MRP practices based on case studies, but very few studies survey-based have been conducted to investigate MRP implementation. None of these studies was conducted in less developed countries. The researcher has attempted to fill some of these gaps in this study by posing three key questions, namely: how have MRP systems been implemented in Egyptian manufacturing companies?, what are the benefits obtained from these which have been implemented?, and what are the explanatory variables of MRP systems effectiveness?. Accordingly, the objectives of the current study are threefold: " To investigate MRP practices in Egyptian manufacturing companies. " To assess the effectiveness of MRP practices measured by the benefits obtained from MRP implementation based on the expectations and perceptions of MRP users in Egyptian manufacturing companies. " To explorea nd examineth e explanatoryv ariableso f MRP systemse ffectiveness. This study has drawn on an extensive review of the literature and previous empirical studies in western industrialised countries and in newly industrialised countries. The strategy used to achieve the research objectives involved quantitative analysis of questionnaire data. Data for the study were collected by a postal questionnaire. One questionnaire was sent out to each company within the Egyptian industrial ex-public sector. Companies were asked if an MRP user in their organisations could respond (production manager or materials manager or inventory control manager or master scheduler or management information systems manager). Of 200 questionnaires sent out, 123 replies were received, giving a response rate of 61.5%. Of the 123 replies, 93 respondents were usable giving a usable response rate of 46.5%: some unusable responses were the result of a high proportion of missing values. The final usable sample was broken-down into respondents from companies which had implemented MRP systems and respondents from non-MRP companies (52: 41). Extensive quantitative methods to analyse questionnaire data were used i. e. Frequency Analysis, Mean Value, Standard Deviation, Mann-Whitney test, T-test, Kruskal Wallis, One Way Analysis of Variance (ANOVA), Paired T-test, Spearman's Correlation Coefficient, Bartlett's test, K-M-O technique, Principal Component of Factor Analysis, Eigenvalue criterion, Varimax Rotation technique, Skewness method, Cook's Distance measure, Scatterplots method, Adjusted R2, OLS technique, Forward and Backward Stepwise strategies and ACE model (Alternating Conditional Expectation technique). This study has provided important insights into the current situation and practices related to rvRP users in Egypt. The main findings of this study indicated that MRP practices in Egypt are relatively similar to those in the newly industrialised countries and in the west. The findings of this research indicated that Egyptian users believe that the expected benefits from MRP implementation have been obtained, though most of the companies which have installed MRP are relative beginners. However, not all MRP users attained the same degree of MRP benefits. Our findings indicated that the MRP benefit-determinant relationships take a nonlinear form for several relationships. Knowledge of this non-linearity may be advantageous for both MRP managers and users in order to manage these relationships effectively for achieving the effectiveness of MRP practices. Finally, valuable implications have been drawn for managers and practitioners to achieve more successful implementation of MRP systems

Towards Better Static Analysis Security Testing Methodologies

Software vulnerabilities have been a significant attack surface used in cyberattacks, which have been escalating recently. Software vulnerabilities have caused substantial damage, and thus there are many techniques to guard against them. Nevertheless, detecting and eliminating software vulnerabilities from the source code is the best and most effective solution in terms of protection and cost. Static Analysis Security Testing (SAST) tools spot vulnerabilities and help programmers to remove the vulnerabilities. The fundamental problem is that modern software continues to evolve and shift, making detecting vulnerabilities more difficult. Hence, this thesis takes a step toward highlighting the features required to be present in the SAST tools to address software vulnerabilities in modern software. The thesis’s end goal is to introduce SAST methods and tools to detect the dominant type of software vulnerabilities in modern software. The investigation first focuses on state-of-theart SAST tools when working with large-scale modern software. The research examines how different state-of-the-art SAST tools react to different types of warnings over time, and measures SAST tools precision of different types of warnings. The study presumption is that the SAST tools’ precision can be obtained from studying real-world projects’ history and SAST tools that generated warnings over time. The empirical analysis in this study then takes a further step to look at the problem from a different angle, starting at the real-world vulnerabilities detected by individuals and published in well-known vulnerabilities databases. Android application vulnerabilities are used as an example of modern software vulnerabilities. This study aims to measure the recall of SAST tools when they work with modern software vulnerabilities and understand how software vulnerabilities manifest in the real world. We find that buffer errors that belong to the input validation and representation class of vulnerability dominate modern software. Also, we find that studied state-of-the-art SAST tools failed to identify real-world vulnerabilities. To address the issue of detecting vulnerabilities in modern software, we introduce two methodologies. The first methodology is a coarse-grain method that targets helping taint static analysis methods to tackle two aspects of the complexity of modern software. One aspect is that one vulnerability can be scattered across different languages in a single application making the analysis harder to achieve. The second aspect is that the number of sources and sinks is high and increasing over time, which can be hard for taint analysis to cover such a high number of sources and sinks. We implement the proposed methodology in a tool called Source Sink (SoS) that filters out the source and sink pairs that do not have feasible paths. Then, another fine-grain methodology focuses on discovering buffer errors that occur in modern software. The method performs taint analysis to examine the reachability between sources and sinks and looks for "validators" that validates the untrusted input. We implemented methodology in a tool called Buffer Error Finder (BEFinder)

INTRODUCTION TO THE VISEGRAD FUND PROJECT: HOW TO PREVENT SMEs FROM FAILURE (Actions based on comparative analysis in Visegrad countries and Serbia)

This issue of Serbian Journal of Management (SJM 14(2) 2019), is dedicated to one very important challenge of contemporary entrepreneurship, that is condensed in single question: How to prevent SMEs from failure ? The articles published in this issue are all addressing different aspects of entrepreneurial activities that can lead to successful and/or unsuccessful operations. Part of the articles pubished in this issue are directly presenting the results of the project: HOW TO PREVENT SMEs FROM FAILURE (Actions based on comparative analysis in Visegrad countries and Serbia), which was financially supported by the International Visegrad Fund. During the projects, researchers from all four Visegrad group countries, as well as researchers from Serbia, were analysing SMEs from their regions, which suffered from some degree of financial distress or have failed in the past. The main purpose of this investigation was to analyse and identify the most important business factors that can lead to failure of the SMEs businesses. Obtained results are presented in this issue. On the other hand, part of the manuscripts in this issue are invited from the authors who are also investigating the SMEs operation and are dealing the factors of success of the entrepreneurial activities, in the region outside Visegrad group or Serbia. The main motive of this issue is to address this highly important challenge - SMEs successful operations