Or Spektrum 

About: Or Spektrum is an academic journal published by Springer Science+Business Media. The journal publishes majorly in the area(s): Computer science & Engineering. It has an ISSN identifier of 0171-6468. Over the lifetime, 527 publications have been published receiving 10771 citations. The journal is also known as: OperationsResearch spectrum (Internet) & OR spectrum (Print).

A survey and annotated bibliography of multiobjective combinatorial optimization

Abstract: This paper provides a survey of the research in and an annotated bibliography of multiple objective combinatorial optimization, MOCO. We present a general formulation of MOCO problems, describe the main characteristics of MOCO problems, and review the main properties and theoretical results for these problems. The main parts of the paper are a section on the review of the available solution methodology, both exact and heuristic, and a section on the annotation of the existing literature in the field organized problem by problem. We conclude the paper by stating open questions and areas of future research.

On the completeness and constructiveness of parametric characterizations to vector optimization problems

Abstract: Motivated by recent reviews of characterizations of optimal solutions to vector optimization problems and by applications to decision support systems, this paper presents a methodological approach to comparing such characterizations. After specifying attributes of constructiveness, alternative classes of characterizations are reviewed. Characterization theorems are quoted or presented in more detail in cases that supplement those given in recent reviews. One of alternative classes of characterizations -- by aspiration levels and order-consistent achievement functions -- is discussed in more detail. An impossibility theorem of complete and robustly computable characterization of efficient (as opposed to weakly or properly efficient) solutions to vector optimization problems is presented. Angeregt durch neuere Ubersichten der Charakterisierung von optimalen Losungen von Vektoroptimierungsproblemen und durch Anwendungen auf Entscheidungsunterstutzungssysteme wird in diesem Beitrag ein methodischer Ansatz zum Vergleich solcher Charakterisierungen dargestellt. Nach der Spezifizierung von Attributen der Konstruktivitat werden alternative Klassen von Charakterisierungen betrachtet. Charakterisierungstheoreme werden entweder zitiert oder, in Erganzung neuerer Ubersichten, dargestellt. Eine der alternativen Klassen der Charakterisierungen wird naher diskutiert. Ein Unmoglichkeitstheorem einer vollstandigen und robust berechenbaren Charakterisierung von effizienten (im Gegensatz zu schwach oder streng effizienten) Losungen der Vektoroptimierungsprobleme wird dargelegt.

A Survey of Priority Rule-Based Scheduling

Abstract: In this paper, we survey the literature on heuristic priority rule-based job shop scheduling. Priority rules have been intensively investigated over the last 30 years by means of simulation experiments. They are also used in Shop Floor Control software systems. We present a classification, a characterization, and an evaluation of elementary priority rules. Some priority rule-related model extensions are discussed.

Vehicle routing and reverse logistics: The vehicle routing problem with simultaneous delivery and pick-up

Abstract: Recently, the increasing focus on environmental protection has led to significant changes in logistics processes In addition to the distribution process to the customers, re-usable packaging and goods to be recycled or remanufactured have to be transported in the reverse direction If both tasks have to be performed simultaneously at the customers' locations which are serviced by a fleet of vehicles stationed in a depot or distribution/redistribution center, the vehicle routing problem with simultaneous delivery and pick-up arises In this paper, the relation between this problem and other vehicle routing problems is investigated A heuristic construction procedure is suggested The proposed algorithm is successfully applied to a real-life problem as well as test instances introduced in the literature earlier In addition, randomly generated instances are tackled in order to try to determine favorable settings for the parameters used in the solution approach

A generalized permutation approach to job shop scheduling with genetic algorithms

Abstract: In order to sequence the tasks of a job shop problem (JSP) on a number of machines related to the technological machine order of jobs, a new representation technique — mathematically known as “permutation with repetition” is presented. The main advantage of this single chromosome representation is — in analogy to the permutation scheme of the traveling salesman problem (TSP) — that it cannot produce illegal operation sequences. As a consequence of the representation scheme a new crossover operator preserving the initial scheme structure of permutations with repetition will be sketched. Its behavior is similar to the well known Order-Crossover for simple permutation schemes. Actually theGOX operator for permutations with repetition arises from aGeneralisation ofOX. Computational experiments show, that GOX passes the information from a couple of parent solutions efficiently to offspring solutions. Together, the new representation and GOX support the cooperative aspect of genetic search for scheduling problems strongly.