Sensitivity of the Optimum to Perturbations of the Profit or Weight of an Item in the Binary Knapsack Problem

In the binary single constraint Knapsack Problem, denoted KP, we are given a knapsack of fixed capacity c and a set of n items. Each item j, j = 1,...,n, has an associated size or weight w_j and a profit p_j. The goal is to determine whether or not item j, j = 1,...,n, should be included in the knapsack. The objective is to maximize the total profit without exceeding the capacity c of the knapsack. In this paper, we study the sensitivity of the optimum of the KP to perturbations of either the profit or the weight of an item. We give approximate and exact interval limits for both cases (profit and weight) and propose several polynomial time algorithms able to reach these interval limits. The performance of the proposed algorithms are evaluated on a large number of problem instances.     

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Ohne Zusammenfassung     

Dual Career Couples als eine Variante von Work-Life-Integration

Dual Career Couples as a form of work-life-integrationThe author discusses the situation of dual career couples, when both are university graduates following an own career. Basing on a respective publication she delineates the current, mostly American research and reports on several German research projects, which endeavour to analyse the relation between gender and inequality in dual career couples.     

Von der Supervision zur Mediation und zurück

From supervision to mediation and vice versaMediation in organizations becomes more and more important because of increasing conflicts. The question is, which competencies of the counsellor are necessary, and above all, whether mediation is a particular method. The author explains the method of mediation and illustrates his concept of “patchwork-mediation”. This procedure allows to build a bridge between supervision and mediation.     

The Management of Violence in a Conflict Organization: The Case of the Abu Sayyaf

The Abu Sayyaf is an organization which has left a trail of mayhem and murder in the southern Philippines for more than a decade. It has gained international notoriety through several high profile mass kidnappings. This article looks at how the Abu Sayyaf has managed to survive and at times prosper despite the state's efforts to eradicate it. By using organizational analysis the paper demonstrates how the Abu Sayyaf has developed structures and processes which make it such a deadly force. The organization has succeeded in gaining considerable fit with the environment in which it operates.     

Ebert. Wolfgang (2001): Systemtheorien in der Supervision — Bestandsaufnahme und Perspektiven

Ohne Zusammenfassung     

Optimization Model and Algorithm for Crew Management During Airline Irregular Operations

Airline irregular operations have long been a realm where human experience and judgement are the most important tools to utilize. Crew management during irregular operations is usually the bottleneck of the whole system-recovering process due to complicated crew schedules and restrictive crew legalities as well as the size and scope of the hub-and-spoke networks adopted by major carriers. A system-wide multi-commodity integer network flow model and a heuristic search algorithm for the above purpose are presented and discussed in this paper. The computational experiences show that the algorithm is efficient enough to solve problems of realistic size and also has the flexibility to accommodate practical business requirements.     

Early experiences of mentoring: Design and use of multimedia materials for teaching OR/MS

The MENTOR project, based at the University of Strathclyde, is producing multimedia computer based learning materials with the aim of improving both the effectiveness and the efficiency of teaching Operational Research/Management Science in higher education. The process of development has been carefully designed to encourage ownership of and commitment to the materials amongst lecturing staff in Universities, with the aim of ensuring widespread use. The paper outlines this process of development and design of materials. Experiences in introducing students to the use of these materials as an integrated part of a Management Science class are reported. Feedback from students has been very positive but also indicates the need for ongoing support and direction.