An integrated production and inventory model for a whole manufacturing supply chain involving reverse logistics with finite horizon period

This paper proposes a model and solution method for coordinating integrated production and inventory cycles in a whole manufacturing supply chain involving reverse logistics for multiple items with finite horizon period. A whole manufacturing supply chain involving reverse logistic consists of tier-2 suppliers supplying raw materials to tier-1 suppliers, tier-1 suppliers producing parts, a manufacturer which manufactures and assembles parts from tier-1 suppliers into finished products, distributors distributing finished products to retailers, retailers selling products to end customers and a third party which collects the used finished products from end customers, dissembles collected products into parts, and feed the parts back to the supply chain. In this system, we consider a finite horizon period. A mathematical model for representing the behaviors of the system is developed. Solution methods based on decentralized and a combination of decentralized and centralized decision making process, referred to as the semi-centralized decision making process, are proposed to solve the model while the centralized decision making process is solved by a mixed integer nonlinear programming method. A numerical example is used to demonstrate the model and the solutions based on the three types of the coordination.     

Suspicious minds: local context and attitude variation across Swedish municipalities

Johansson Sevä I. Suspicious minds: local context and attitude variation across Swedish municipalities
Int J Soc Welfare 2010: 19: 225–235 © 2009 The Author(s), Journal compilation © 2009 Blackwell Publishing Ltd and the International Journal of Social Welfare. This article investigates whether degree of suspicion of welfare abuse relates to local context in Sweden. It is suggested that certain features of Swedish municipalities can create a local information bias influencing individual suspicion of welfare abuse. Prevalence of social problems and political climate are features of the municipal context having the potential to influence opinion formation. Social problems are captured by local unemployment, social assistance and ill‐health rates. Political climate is captured by electoral support for conservatives. The results indicate that local context can influence suspicion of welfare abuse, contexts where social problems are widespread reduce such suspicion. While local political climate seems important in itself, it also interacts with social problem level, increasing suspicion if a conservative political climate and social problems coexist. While social problems seem to generate less suspicion regarding social policy abuse, they also provide ‘raw material’ for political rhetoric regarding suspicion.     

Aussiedler and Ausländer:* Transforming German national identity

Abstract

I analyse the changing conceptions of German national identity since the idea was first articulated after the French Revolution. I distinguish between universalist concepts of national belonging and particularist ones, specifying at the same time their respective class articulations. Within this context, I address both historical and contemporary politico‐legal conditions for German citizenship. These conditions for German belonging entail differential treatment for ethnic Germans coming from beyond the borders of the German state (Aussiedler), whether West Germany before unification or united Germany since, and foreigners living under direct German jurisdiction (Ausländer). The claimed bases and inclusionary/exclusionary effects of these differentiations are interrogated, and their contemporary political implications assessed.     

Sequential confidence intervals for the number of cells in a multinomial population

A two-sided sequential confidence interval is suggested for the number of equally probable cells in a given multinomial population with prescribed width and confidence coefficient. We establish large-sample properties of the fixed-width confidence interval procedure using a normal approximation, and some comparisons are made. In addition, a simulation study is carried out in order to investigate the finite sample behaviour of the suggested sequential interval estimation procedure.     

Blinded sample size re-estimation in clinical trials comparing several treatments

An important question that arises in clinical trials is how many additional observations, if any, are required beyond those originally planned. This has satisfactorily been answered in the case of two-treatment double-blind clinical experiments. However, one may be interested in comparing a new treatment with its competitors, which may be more than one. This problem is addressed in this investigation involving responses from arbitrary distributions, in which the mean and the variance are not functionally related. First, a solution in determining the initial sample size for specified level of significance and power at a specified alternative is obtained. Then it is shown that when the initial sample size is large, the nominal level of significance and the power at the pre-specified alternative are fairly robust for the proposed sample size re-estimation procedure. An application of the results is made to the blood coagulation functionality problem considered by Kropf et al. [Multiple comparisons of treatments with stable multivariate tests in a two-stage adaptive design, including a test for non-inferiority, Biom. J. 42(8) (2000), pp. 951–965].     

On computer generation of gamma random variables by rejection and composition procedures 2

The paper presents various algorithms for generating gamma random variables, by combining rejection and composition procedures. Two efficient algorithms are given for the case when the parameter of the gamma distribution is 0<v<l. For the case vl, several algorithms are given but they (except one), work reliably only for small values of v. Results of some computer tests together with FORTRAN subroutines are also presented.