Basic of Fault Tree (FT) method

A fault tree described the logical relationship between events and causes. This method shows significant success in analyzing the root cause of an accident. This paper will review the basics of the Fault Tree (FT) method including the structure, factors that contribute and FT application

Middleware-based Database Replication: The Gaps between Theory and Practice

The need for high availability and performance in data management systems has been fueling a long running interest in database replication from both academia and industry. However, academic groups often attack replication problems in isolation, overlooking the need for completeness in their solutions, while commercial teams take a holistic approach that often misses opportunities for fundamental innovation. This has created over time a gap between academic research and industrial practice. This paper aims to characterize the gap along three axes: performance, availability, and administration. We build on our own experience developing and deploying replication systems in commercial and academic settings, as well as on a large body of prior related work. We sift through representative examples from the last decade of open-source, academic, and commercial database replication systems and combine this material with case studies from real systems deployed at Fortune 500 customers. We propose two agendas, one for academic research and one for industrial R&D, which we believe can bridge the gap within 5-10 years. This way, we hope to both motivate and help researchers in making the theory and practice of middleware-based database replication more relevant to each other.Comment: 14 pages. Appears in Proc. ACM SIGMOD International Conference on Management of Data, Vancouver, Canada, June 200

REGENERATIVE MECHANISMS TO RESOLVE CONTRACTOR COMMITMENT CHALLENGES IN PROJECT DELIVERY

Published Conference ProceedingsPerformance of participants on a contract is important for its successful delivery. It is an indication of competency, measure of productivity and quality levels of the project. Lack of contractors’ commitment is observed to be one of the major barriers in effective execution of contracts and consequent successful project delivery. This investigation was aimed at to explore how contractor commitment challenges can be resolved to improve their performance in the project delivery. A questionnaire survey was conducted among 88 stakeholders that include clients, architects, contractors, quantity surveyors, structural engineers and project managers. Stratified random sampling technique was used for the selection of respondents and the survey was administered through post and e-mail. The contractor commitment challenge variables were evaluated by using Likert scale. The inter-linkage among the variables was established based on literature findings and relevant statistical tests. Followed by System Dynamics (SD) principle based on System thinking approach, was adopted to extract the causal feedback mechanisms that cause contractor commitment challenges and to evolve plausible policy interventions to resolve the challenges. Findings suggest that lack of experience, skill, inadequate supervision, and lack of control over the subcontractors leads to contractor’s inefficiency. Poor planning and scheduling, poor professional management, poor execution of projects, ineffective/outdated equipment, and inefficiency of labour force result in poor quality of work and delay. In addition, design and documentation challenges disrupt the contractors’ schedule. These hinder contractor commitment. However, four policy/strategic interventions were evolved based on dynamic hypotheses: they are the causal feedback relationships among (1) contractor efficiency and capacity building; (2) professional management; (3) construction methods; and (4) involvement of the contractor and client in the design process. These would enable the contractors to meet their commitment and overcome their challenges and improve their efficiency in project delivery

SAW-TOPSIS Implementation To Determine An Appropriate DBMS Software

Selection an appropriate Database Management Software, is a crucial part to ensure operational excellence businesses firm. Database management software used to organize and manage the company’s data so that they can be efficiently accessed and used to improve operational and decision quality. However, a senior manager as decision maker sometimes lacks the comprehensive knowledge to choose a suitable database management software which meets with business needs. Then, The manager determines a database management software based on a consultant or vendor offer. On the other hand, a consultant or vendor has an interest in to sell their product, so they tend to lead manager to choose their product even though it is not fulfilling business needs. We present a decision support application to help the manager to select an appropriate database management software (DBM) for their company, using Simple Additive Weighting (SAW) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method. We observe SQL Server, MySQL, Oracle, DB2, and PostgreSQL as five top database management software and investigate the detail about cost, storage capacity, security, supported the operating system and supported programming language as key criteria to select best database management software from their official website. Then, we combining SAW and TOPSIS method to choose the best appropriate DBM software based on user requirement through computation program and validate our application performance includes the user interface, usability and accuracy result to 50 database engineers expert as respondent. The results are as follows; 1) 86 % of respondents are satisfied with application user interface, 2) 94% are happy with application usability and 3) 86% are pleased with the accuracy of the computation. Overall, this study provides a decision support application to determine an appropriate database management software based on business needs by combining SAW and TOPSIS methods

Analytical response time estimation in parallel relational database systems

Techniques for performance estimation in parallel database systems are well established for parameters such as throughput, bottlenecks and resource utilisation. However, response time estimation is a complex activity which is difficult to predict and has attracted research for a number of years. Simulation is one option for predicting response time but this is a costly process. Analytical modelling is a less expensive option but requires approximations and assumptions about the queueing networks built up in real parallel database machines which are often questionable and few of the papers on analytical approaches are backed by results from validation against real machines. This paper describes a new analytical approach for response time estimation that is based on a detailed study of different approaches and assumptions. The approach has been validated against two commercial parallel DBMSs running on actual parallel machines and is shown to produce acceptable accuracy

A Cross-Platform Database Infrastructure Monitoring Dashboard for The Hanover Insurance Group

This MIS MQP developed a cross-platform database infrastructure monitoring dashboard for The Hanover Insurance Group. Both technical details and executive level insight are comprehensively represented. Critical health and performance information from four database platforms that support over 2,000 databases is integrated with independent monitoring tools in one centralized dashboard. Increasing database monitoring efficiency and cross-organizational communication, the dashboard is a lean implementation tool designed to transform Hanover\u27s reactive monitoring approach into a proactive one