Asymptotically Optimal Approximation Algorithms for Coflow Scheduling

Many modern datacenter applications involve large-scale computations composed of multiple data flows that need to be completed over a shared set of distributed resources. Such a computation completes when all of its flows complete. A useful abstraction for modeling such scenarios is a {\em coflow}, which is a collection of flows (e.g., tasks, packets, data transmissions) that all share the same performance goal. In this paper, we present the first approximation algorithms for scheduling coflows over general network topologies with the objective of minimizing total weighted completion time. We consider two different models for coflows based on the nature of individual flows: circuits, and packets. We design constant-factor polynomial-time approximation algorithms for scheduling packet-based coflows with or without given flow paths, and circuit-based coflows with given flow paths. Furthermore, we give an $O(\log n/\log \log n)$-approximation polynomial time algorithm for scheduling circuit-based coflows where flow paths are not given (here $n$ is the number of network edges). We obtain our results by developing a general framework for coflow schedules, based on interval-indexed linear programs, which may extend to other coflow models and objective functions and may also yield improved approximation bounds for specific network scenarios. We also present an experimental evaluation of our approach for circuit-based coflows that show a performance improvement of at least 22% on average over competing heuristics.Comment: Fixed minor typo

ASSESSING STUDENTS’ SATISFACTION WITH QUALITY OF SERVICE OF STUDENTS INFORMATION SYSTEM

With the increasing number of higher education institutions in Jordan, universities are competing to attract more students. To achieve this goal, the universities are competing to provide the students with all possible satisfaction means through providing efficient e-services. This paper measures the satisfaction of the students at Al-Hussein Bin Talal University, Jordan, with the quality of e-services. It mainly concentrates on the students’ satisfaction with the in-house developed Student Information System (SIS). To measure the satisfaction of the students, a questionnaire was developed and distributed to a sample of the university students. The questionnaire forms were collected and analyzed. The results of the questionnaire showed that the students were satisfied by the transition to e-services and the SIS has a positive impact on the students’ satisfaction. The research also provides the university with some suggestions to improve the SIS and, therefore, meet the demand of the students.Student Information Systems (SIS), Student satisfaction, SERVQUAL, quality of service.

On Multiplication Groups of Quasigroups

Quasigroups are algebraic structures in which divisibility is always defined. In this thesis we investigate quasigroups using a group-theoretic approach. We first construct a family of quasigroups which behave in a group-like fashion. We then focus on the multiplication groups of quasigroups, which have first appeared in the work of A. A. Albert. These permutation groups allow us to study quasigroups using group theory. We also explore how certain natural operations on quasigroups affect the associated multiplication groups. Along the way we take the time and special care to pose specific questions that may lead to further work in the near future

Diverging trends in unemployment in the United States and Europe: Evidence from Okun’s law and the global financial crisis

The global financial crisis deeply impacted labour markets around the globe, particularly in a number of OECD countries. However, in such cases as the United States, some commentators have argued that the subsequent rise in unemployment has exceeded previous estimates of the elasticity of the unemployment rate with respect to output growth, a statistical relationship known as Okun’s law. In line with the literature on this topic, the estimates of Okun’s coefficients presented in this paper display considerable variation across countries, which captures the heterogeneity in the responsiveness of unemployment to the global financial crisis. In the United States, Canada, Spain and other severely affected economies, the coefficient increased sharply, departing from pre-crisis levels in the 2000s. In other countries where unemployment has remained subdued, namely Germany and the Netherlands, the coefficient has fallen dramatically. While different factors can potentially explain how the crisis has been transmitted to the labour market, the role of labour market institutions is the focus of this paper. In this regard, empirical evidence exploring the relationship between the shift in Okun’s coefficients and such institutions confirms that the responsiveness in the unemployment rate during the Great Recession was lower in countries where workers are afforded greater employment protection (such as Germany).unemployment / employment / employment security / labour legislation / comment / economic recession / OECD countries / USA

The Extent of the Application of the Rules of Governance on Industrial Public Joint- Stock Companies Enlisted in Amman Stock Exchange

This study aims to study the extent of applying the governance standards on the public joint-stock industrial corporations listed in Amman stock market.  Some concepts of governance have been discussed, the principles of governance clarified, identify the criteria, objectives and the importance of governance. We used a questionnaire to point out the extent the companies apply the principles and criteria of governance and make sure if the corporate separated the duties of the Executive Director and Finance Director  for the purpose of prevention fraud or embezzlement of the  shareholders funds, as well as to achieve the separation between the job of the Chairman of the Board of Directors and his Deputy, and allow publishing realistic reports of the auditors in respect of the performance of the Jordanian companies, which are the basics and fundamentals of institutional governance and the most important result concluded by the study.  It has been found that the Jordanian companies are still (up to date) suffer from the conflict of interests between the its Board of Directors, remaining shareholders and family companies, beside the singularity of the management in taking the decisions to their own interests supported by various financial legislations. the study recommended that the companies listed on the stock market in Jordan to upgrade the application level of corporate governance rules effectively, so that would encourage investors to invest in the companies that provide protection for shareholders, deal in transparency, full disclosure in financial reports and independent of boards of directors

BUSINESS INTELLIGENCE CAPABILITIES' EFFECTS ON PERFORMANCE IN A COMPETITIVE ENVIRONMENT STUDYING ON-SITE AT THE TOUCHES FOUNDATION FOR ART AND INNOVATION

Abstract This study aims to determine how the touches Foundation for Innovation and the Arts' competitive performance was impacted by its business intelligence capabilities. All 63 members of the touches Foundation for Innovation and the Arts make up the study community. The study's methodology was based on a scoring descriptive approach that identified two aspects-the first of which was business intelligence capabilities-and three other dimensions. These are (business intelligence techniques, business intelligence structure, and business intelligence culture) and competitive performance after four dimensions (cost, quality, flexibility. access) According to the study's findings, the Touches Foundation for Innovation and the Arts employees had an average degree of business intelligence across all of its aspects. The study's findings also indicated that the Touches Foundation for Innovation and the Arts employees' level of performance in a competitive environment was average additionally, the findings of the regression equation have demonstrated that there are statistically significant disparities between competitive performance and business intelligence skills across all dimensions. The study's conclusion included a number of recommendations, including educating the company's leadership and workers about the importance of acquiring business intelligence skills in order to enhance the operation of the company and take advantage of future business prospects