Efficient Job Scheduling Algorithms with Multi-Type Contentions

In this paper, we consider an interesting generalization of the classic job scheduling problem in which each job needs to compete not only for machines but also for other types of resources. The contentions among jobs for machines and for resources could interfere with each other, which complicates the problem dramatically. We present a family of approximation algorithms for solving several variants of the problem by using a generic algorithmic framework. Our algorithms achieve a constant approximation ratio (i.e., 3) when there is only one type of resources or certain dependency relation exists among multiple types of resources. When the r resources are unrelated, the approximation ratio of our algorithm becomes k+2, where k≤ r is a constant depending on the problem instance. As an application, we also show that our techniques can be easily applied to optical burst switching (OBS) networks to design more efficient wavelength scheduling algorithms.This research was supported in part by an IBM faculty partnership award, and an IRCAF award from SUNY Buffalo.     

Lean road transportation – a systematic method for the improvement of road transport operations

Road transportation has become an important factor in international trade and the management of supply chains. However, this form of product logistics has generally been considered inefficient. Traditionally, practical inefficiencies of road transportation have been addressed through mathematical modelling, operations research-based methods and simulation. This paper presents an alternative systematic approach to improve road transport operations based on lean thinking and the reduction of the seven transportation extended wastes. To do this, the paper reviews the extant literature in the area of lean road transportation, providing a structured research definition of the application of lean thinking in road transport operations and hence guidance on the limited research conducted in this field. The systematic lean transportation method is then presented and empirically tested through a case study in a Mexican firm. The results obtained from the case study indicate that the proposed systematic lean method is an effective alternative for the improvement of road transport operations, with the number of distribution routes and distance travelled being reduced by 27 and 32%, respectively. The proposed method can be used by organisations as a guide to help them improve their road transport operations. In addition, the paper’s aim is to contribute by stimulating scholars to further study the application of lean thinking and waste reduction in road transport operations.     

Characterization results based on dynamic Tsallis cumulative residual entropy

In this article, the concept of cumulative residual entropy (CRE) given by Rao et al. (2004 Rao, M., Chen, Y., Vemuri, B.C., Wang, F. (2004). Cumulative residual entropy: A new measure of information. IEEE Trans. Inf. Theory 50:1220–1228.[Crossref], [Web of Science ®] , [Google Scholar]) is extended to Tsallis entropy function and dynamic version, both residual and past of it. We study some properties and characterization results for these generalized measures. In addition, we provide some characterization results of the first-order statistic based on the Tsallis survival entropy.     

印度汽车市场崛起

尽管大多数印度人依然在用两轮交通工具,但新兴的印度中产阶级却给汽车销售业带来了有力的推动——至少当下如此。     

Exponentiated Teissier distribution with increasing,decreasing and bathtub hazard functions

This article introduces a two-parameter exponentiated Teissier distribution. It is the main advantage of the distribution to have increasing, decreasing and bathtub shapes for its hazard rate function. The expressions of the ordinary moments, identifiability, quantiles, moments of order statistics, mean residual life function and entropy measure are derived. The skewness and kurtosis of the distribution are explored using the quantiles. In order to study two independent random variables, stress–strength reliability and stochastic orderings are discussed. Estimators based on likelihood, least squares, weighted least squares and product spacings are constructed for estimating the unknown parameters of the distribution. An algorithm is presented for random sample generation from the distribution. Simulation experiments are conducted to compare the performances of the considered estimators of the parameters and percentiles. Three sets of real data are fitted by using the proposed distribution over the competing distributions.     

An extended Maxwell distribution: Properties and applications

In this article, we propose an extension of the Maxwell distribution, so-called the extended Maxwell distribution. This extension is evolved by using the Maxwell-X family of distributions and Weibull distribution. We study its fundamental properties such as hazard rate, moments, generating functions, skewness, kurtosis, stochastic ordering, conditional moments and moment generating function, hazard rate, mean and variance of the (reversed) residual life, reliability curves, entropy, etc. In estimation viewpoint, the maximum likelihood estimation of the unknown parameters of the distribution and asymptotic confidence intervals are discussed. We also obtain expected Fisher’s information matrix as well as discuss the existence and uniqueness of the maximum likelihood estimators. The EMa distribution and other competing distributions are fitted to two real datasets and it is shown that the distribution is a good competitor to the compared distributions.     

Changes in Management Ownership and the Valuation Effects of Equity Offerings

Seasoned equity issues trigger share price declines, and this is usually interpreted as evidence of signalling. We find that seasoned equity issues also typically result in much lower managerial ownership in U.S. firms. Jensen and Meckling (1976) predict a stock price decline when managerial ownership falls. We conduct several tests to distinguish agency explanations form signalling explanations, and conclude that both effects are present.     

ACCOUNTING FOR DEBASEMENTS: INDIVISIBILITY OR IMPERFECT RECOGNIZABILITY OF MONEY

The widespread prevalence of debasements in medieval Europe constitutes a puzzle under standard price theory because people voluntarily exchanged heavy coins for lighter ones; the difference being kept as seigniorage. I explore two properties of commodity monies that might make holding light coins more desirable, namely indivisibility and imperfect recognizability. If the agent trades indivisible coins, there are inefficiencies arising from over production of goods when the agent uses the heavier coin. Also, when coins are imperfectly recognizable, the heavy coin faces adverse selection. I find that under some parameters, indivisibility by itself leads to positive revenue following debasements, but in a way that eliminates co-circulation of coins. While with a sufficient degree of imperfect information, debasements can generate positive revenue and also co-circulation of coins. (JEL D82, D83, E40, E42, N10)     

Performance management of suppliers in outsourcing project: case analysis from the financial services industry

This study investigates the characteristics of an effective performance management framework for outsourcing projects in a UK-based financial services organisation and how this may contribute to the success of the outsourcing arrangement. The analysis draws on outsourcing and performance management theory, and uses both primary and secondary data. Valuable information was found on objective setting, performance measurement and performance improvement in the outsourcing project. An adapted version of the Balanced Scorecard, termed a Logic Scorecard, is suggested as a measurement tool; a service credit system and a continuous improvement schedule used to enhance supplier performance. The performance management framework, which is one of the pillars of the supply chain operations reference (SCOR) model, was developed, and provides practitioners with step-by-step guidance for the implementation of performance management in outsourcing projects. This combines both suggestions for performance management before and after the outsourcing decision, thus considering the entire outsourcing lifecycle. The proposed 10-step framework for outsourcing not only incorporates strategic propositions but also shows its implementation at an operational level.