09261 Abstracts Collection -- Models and Algorithms for Optimization in Logistics

From June 21 to June 26, 2009 the Dagstuhl Seminar Perspectives Workshop 09261 ``Models and Algorithms for Optimization in Logistics \u27\u27 was held in Schloss Dagstuhl~--~Leibniz Center for Informatics. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available

Communications

The communications sector of an economy comprises a range of technologies, physical media, and institutions/rules that facilitate the storage of information through means other than a society\u27s oral tradition and the transmission of that information over distances beyond the normal reach of human conversation. This chapter provides data on the historical evolution of a disparate range of industries and institutions contributing to the movement and storage of information in the United States over the past two centuries. These include the U.S. Postal Service, the newspaper industry, book publishing, the telegraph, wired and cellular telephone service, radio and television, and the Internet

Modelling and Performance Evaluation of Containerised Parcel Delivery

This paper investigates different factors that affect the performance of containerised transportation in parcel delivery networks. Motivated by a situation facing a postal delivery company in Australia, we study how container utilisation rate, sortation activities, and changes in cost parameters can affect the overall performance of a parcel delivery network. Mixed-integer programming and machine learning are employed to model a realistic parcel delivery network considering sortation activities and to evaluate the performance of this network using data from a major postal service provider. The findings of this study can help parcel delivery companies to make more informed investment decisions and introduce more effective performance improvement initiatives

Spatial organization of public services: models and applications

Location decisions are crucial in the spatial organization in both public and private sectors as they can have a long term impact on operational performances and on service levels. Social cost minimization, universality of services and equity, expressed in terms of users' accessibility, are the main objectives in public services contexts. Nevertheless, the enduring trend of public expenditures revision poses, also in the public sectors, the need to pursue objectives of economic efficiency. In the literature, two families of optimization problems are typically used to address these problems, namely Facility Location Problems (FLPs) and Districting Problems (DPs). The aim of this thesis is to show how FLPs and DPs can be used to underpin spatial organization processes of public services, providing analytical models able to assist the decision making. To this end, novel mathematical models are developed with application to the healthcare and postal service sectors. In particular, a hierarchical facility location model is formulated to reorganize an existing regional Blood Management System (BMS) while an integrated location-districting model is proposed for the organization of postal collection operations in urban areas. A constructive heuristic procedure is also devised to solve the latter problem. Extensive computational experiments are realized to validate the proposed models and to show their capability to provide insightful managerial implications. Finally, the thesis aims at filling another existing gap in the literature due to the absence of stochastic models for DPs. Hence, a two-stage stochastic program for districting is introduced and tested on real georgaphic data. Several extensions of the proposed modeling framework are also discussed

U.S. Postal Service: The Service's Strategy for Realigning Its Mail Processing Infrastructure Lacks Clarity, Criteria, and Accountability

A letter report issued by the Government Accountability Office with an abstract that begins "With declining mail volumes, increasing compensation costs, and a more competitive marketplace, the need for the U.S. Postal Service (Service) to increase efficiency and reduce expenses is a matter of increasing importance and concern. According to the Service, one area where it can become more efficient is in its mail processing and distribution infrastructure. The objectives of this report are to (1) describe major business and demographic changes and their effect on the Service's mail processing and distribution infrastructure; (2) describe what actions the Service is taking in response to these changes, and what challenges exist; and (3) discuss the Service's strategy for realigning its infrastructure.

Traffic Flows Model of Postal Items Based on Input-output Demands in the Public Postal Network: Case Study of Croatia

This paper presents the method for developing matrix model of postal traffic flows (ordinary communication items) in public postal network according to volume and different end-to-end (E2E) processes, which can be used for selecting of relevant model for accessing the public postal network. The presented traffic matrix model can be adjusted after the measurement of real volumes and selecting the numbers of different E2E processes (according to geographical input-output request). During the simulation of the model it could be possible to detect the optimal solution for accessing the public postal network. KEY WORDS: traffic modelling, postal services, access to the public postal networ