Jacek Żak

The Design of the Physical Distribution System with the Application of the Multiple Objective Mathematical Programming. Case Study

The paper presents the multiobjective optimization of the all-Polish physical distribution system of cosmetics, detergents and washing articles. The research report refers to a real life case. The optimization process is focused on minimization of both total distribution cost and the delivery time within the distribution system. The primary concern of the project is to define the number and the location of the warehouses in the distribution network. The optimization process leads to the redesign of the existing distribution system. The problem is formulated in terms of bi-criteria mathematical mixed-integer programming. It has been solved with the application of an extended version of MS Excel Solver — Premium Solver Plus. A set of Pareto-optimal distribution systems has been generated. The number of Regional Distribution Centers (RDC-s) ranges from 7 to 23 in Pareto-optimal solutions. The results of the experiment are promising.

The Methodology of Multiple Criteria Decision Making/Aiding as a System-Oriented Analysis for Transportation and Logistics

The paper presents the principles of Multiple Criteria Decision Making/Aiding (MCDM/A) and its application in transportation and logistics. The Methodology of MCDM/A is presented as a universal, system-oriented tool of analyzing complex objects, problems and systems, including transportation/logistics decision problems. The article describes basic notions and concepts associated with MCDM/A methodology. It presents the rules, procedures and paradigms of MCDM/A and points out their resemblance to System Analysis. The author presents the process of Multiple Criteria Decision Making/Aiding and explains all its phases, bodies involved and generated results. The theoretical background is supported by a real world case study focused on the analysis, mathematical modeling and solution procedure of a multiple criteria crew sizing problem for a freight transportation and delivery process. The decision problem is solved in a two-stage procedure composed of: generation of a set of Pareto optimal solutions by a heuristic method and their review and selection of the compromise solution by an interactive method with graphical facilities (LBS method). The case study shows practical applicability of the presented approach.

Multiple Criteria Evaluation of Suppliers in Different Industries - Comparative Analysis of Three Case Studies

The chapter presents the comparative analysis of the solution procedures of the suppliers’ selection problem in different industries. The authors carry out a multiple criteria evaluation and ranking of three distinctive categories of suppliers, i.e.: meat suppliers in a food industry, logistics service providers (LSPs) in a household chemistry industry and suppliers of packaging and supplementary materials in a printing industry. The definition of variants (suppliers), family of evaluation criteria and modeling of the decision maker’s (DM’s) preferences are presented. The results of computational experiments performed with the application of Electre III/IV and AHP methods are demonstrated. The processes of selecting the most desired suppliers in the above mentioned cases are compared and different aspects of the proposed multiple criteria - based procedures are thoroughly discussed.

The Multiple Criteria Optimization Problem of Joint Matching Carpoolers and Common Route Planning

The paper concerns a joint problem of matching carpoolers and planning common routes as a multiple criteria optimization problem. The model of the optimization problem, as well as the concept of solution procedure, is presented. The solution algorithm uses dynamic programming method and Dijkstra algorithm to obtain matches of the carpoolers and routes. The solution is evaluated by aggregated quality index taking into account preferences of carpoolers equally, concerning all the criteria. Preferences are obtained by AHP method.

A Methodology of Redesigning and Evaluating Medium-Sized Public Transportation Systems

The chapter presents a generic methodology of carrying out a comprehensive redesign of a public transportation system. The proposed paradigm can be applied by municipal authorities (local governments) and management of urban transportation systems to upgrade local transportation. The authors propose two major stages of this methodology: 1. A heuristic construction of the public transportation system redesign variants/scenarios; 2. Multiple criteria evaluation of these scenarios. In the first stage 6 redesign concepts of the public transportation system are developed. The variants are constructed heuristically, based on “common sense”, best practices and authors’ expert knowledge in the field. In the second stage, the evaluation of redesign scenarios is defined as a multiple criteria ranking problem. A consistent family of criteria is defined, preferences of the decision maker (DM) and stakeholders are identified and modeled, and finally computational experiments are performed. In the computational phase selected Multiple Criteria Decision Making/Aiding (MCDM/A) methods, such as: AHP and ELECTRE III/IV are applied. The analysis is carried out based on a real world case study in a medium sized city in Poland. The generated results are compared with the intuitive decisions made by the officers of the local Town Hall.

Design and Evaluation of Transportation Systems

The paper presents the state-of-the-art in the fields of designing and evaluating complex transportation systems. Both components (design and evaluation) are presented as separate phases of a combined methodology and its major concepts and rules are described. Three alternative approaches to design/redesign of the transportation systems are presented, including: heuristic (intuitive - oriented) design supported by simulation, optimization (mathematical programming) - based design and hybrid approach based on the application of several combined procedures, including the 4-stage model. In the evaluation phase two major concepts are described, such as: Cost Benefit Analysis (CBA) and its variations and Multiple Criteria Analysis (MCA). The real life case study, focused on the heuristic redesign of the section of the transportation system, construction of alternative transportation solutions and their multiple criteria evaluation, is demonstrated.

The Application of Dominance-based Rough Sets Theory to Evaluation of Transportation Systems☆

The paper presents an original procedure of evaluation of a transportation system, resulting in its assignment into a predefined class, representing the overall standard of the considered system and the level of transportation service. The method relies on the application of the dominance-based rough set theory (DRST), allows for thorough data exploration, evaluation of informational content of the considered characteristics and generation of certain decision rules that support t he evaluation process. In the analysis different characteristics (criteria and attributes) describing various aspects of a transportation system operations are taken into account. The assignment of a transportation system to a specific quality class is performed based on the values of characteristics which are compared with the evaluation pattern, i.e. the set of decision rules generated through the analysis of customers’ opinions and expectations concerning a transportation system. The method is composed of three major steps, including: 1) identification of the most important characteristics, 2) generation of the evaluation pattern, and 3) assignment of the transportation system to the appropriate class. In the evaluation process five key components of a transportation system, including: transportation means, human resources, informational resources, transportation infrastructure and technical equipment as well as organizational rules are considered.