A comparability graph is a graph which admits a transitive orientation. In this paper we consider the problem of augmenting a graph to a comparability graph in such a way that the maximum weight of its cliques is mini...
详细信息
A comparability graph is a graph which admits a transitive orientation. In this paper we consider the problem of augmenting a graph to a comparability graph in such a way that the maximum weight of its cliques is minimum. the problem is equivalent to a multiprocessor scheduling problem and to the interval coloring problem;and in the unweighted case also to the chromatic number problem. In the general case, the problem is NP-hard in the strong sense even on some very simple types of perfect graphs. We give complexity and approximation results for two subclasses of perfect graphs, namely for split graphs and stars of cliques, for which the problem still remains intractable but admits efficient estimations.
We consider the case of minimizing the makespan when scheduling tasks with respect to a class of so-called forbidden sets, i.e. sets of tasks that are not allowed to be scheduled in parallel. Following the notion of G...
详细信息
We consider the case of minimizing the makespan when scheduling tasks with respect to a class of so-called forbidden sets, i.e. sets of tasks that are not allowed to be scheduled in parallel. Following the notion of Graham et al. [7], the treated problem will be abbreviated by P infinity\FS\C-max. this problem is NP hard even for unit task length and forbidden sets that contains exactly two elements. Moreover, we show that the existence of a polynomial-time approximation algorithm with a worst-case ratio strictly less than 2 implies P = NP. We point out that the corresponding re-optimization problem (after changing the instance slightly) is NP hard as well, even if only one forbidden set is added or removed. Furthermore, the latter re-optimization problems have approximation thresholds of 3/2 and 4/3, respectively. To conclude our results, we show that the bound of 3/2 is light for the case of re-optimizing an optimal schedule after adding a new forbidden set.
the proceedings contains 84 papers from the 6th IEEE International workshop on Robot and Human Communication. Topics discussed include: ultimate problems of human-robot communication;human-robot cooperative work;path ...
详细信息
the proceedings contains 84 papers from the 6th IEEE International workshop on Robot and Human Communication. Topics discussed include: ultimate problems of human-robot communication;human-robot cooperative work;pathplanning;autonomous robots;humanoid robots;teleoperation;human-robot interfaces;human skills and intelligent control;genetic algorithms;human science;safety aspect of human interfaces;emotions;face relations;verbal communications;virtual reality/cooperation/haptic interfaces;and human machine interfaces.
this paper describes a GA for job shop schedulingproblems. Using the Giffler and thompson algorithm, we created two new operators, thX crossover and mutation, which better transmit temporal relationships in the sched...
详细信息
the proceedings contain 50 papers. the special focus in this conference is on Design Environments and Tools. the topics include: A system for designing parallel processor arrays;on the role of architectures in systems...
ISBN:
(纸本)3540638113
the proceedings contain 50 papers. the special focus in this conference is on Design Environments and Tools. the topics include: A system for designing parallel processor arrays;on the role of architectures in systems engineering;an approach to safety critical systems design;extensions and semantics of controller state diagrams for practical applications;design and implementation of an energy management system for an integrated iron and steel plant;representation and management of memory and decision in evolving software systems;a generic engineering framework for mechanical engineering based upon meta models;formal representation and proof of the interpreted sequential machine model;modelling of concurrent and embedded systems;a dense-time temporal logic with nice compositionality properties;introducing planning in discrete event systems;multirate control of a class of nonlinear systems;global structural approximate controllability of polynomial nonlinear systems;vectorized simulations of normal processes for first crossing-time problems;an architecture for complex systems;design of nonlinear lag-lead compensators by extended linearization using symbolic computation techniques;a numerical computation for declarative expressions;an automatic calculator with penrose diagrams;cognitive modeling for navigation of mobile robots using the sensory gradient concept;fuzzy traffic police for autonomous vehicles;object-oriented model of an open communication architecture for flexible manufacturing control;a formal model for integrated system development;moving towards an agent-based engineering environment;experiencing modeling and development of an intelligent autonomous robot;modular control system for robotized cells and lines and latest developments in robotics.
this seminar proceedings contains 27 papers. the main topics discussed are: alternative FMS designs;inventory valuation methods;bicriteria schedulingproblems;decision criteria in capital budgeting;investment in elect...
详细信息
this seminar proceedings contains 27 papers. the main topics discussed are: alternative FMS designs;inventory valuation methods;bicriteria schedulingproblems;decision criteria in capital budgeting;investment in electronic design, flexible capacity;due date setting;decision support systems for personnel planning, demand shift planning;optimal order quantities;production systems design;economic lot sizing;optimal strategies in inventory systems;generic bill-of-material;optimal pricing in a job shop;customer service levels;production system location;complexity index in decision making;strategic aspects of flexible production technologies;CIM networking;cellular manufacturing;stochastic multiechelon production systems;manufacturing practices;multicriteria models for capacity analysis and aggregate planning.
A series of experiments to learn general rules for simple job shop scheduling tasks suggest that the classifier system may work best as a component of a larger system. Preliminary results demonstrate the system's ...
详细信息
Abstraction is a powerful technique that reduces the size of large search spaces encountered during problem solving. Recently, techniques for automatically generating appropriate abstractions have been developed. Curr...
详细信息
An improved scheduling algorithm has been devised to determine the optimal sequence in which products and byproducts would be produced and the times at which the various production operations for each product should b...
详细信息
An improved scheduling algorithm has been devised to determine the optimal sequence in which products and byproducts would be produced and the times at which the various production operations for each product should be carried out to meet a given product demand pattern, taking into account the available equipment, stockholding costs and penalties introduced by stopovers. the proposed methodology allows for solution to real, complex problemsthanks to the use of a new improved hybrid combination of heuristic and deterministic algorithms. Production planning in an already existing plant has also been succesfully achieved for medium-term production using alternate dynamic programming and integer-linear programming with restrictions. the algorithms have proven to be very fast when compared with deterministic methods.
this proceedings volume consists of papers presented at the Sixth International workshop on Computer-Aided scheduling of Public Transpon, which was held at the Fund~lio Calouste Gulbenkian in Lisbon from July 6th to 9...
详细信息
ISBN:
(数字)9783642577628
ISBN:
(纸本)9783540601937
this proceedings volume consists of papers presented at the Sixth International workshop on Computer-Aided scheduling of Public Transpon, which was held at the Fund~lio Calouste Gulbenkian in Lisbon from July 6th to 9th, 1993. In the tradition of alternating workshops between North America and Europe - Chicago (1975), Leeds (1980), Montreal (1983), Hamburg (1987) and again Montreal (1990), the European city of Lisbon was selected as the venue for the workshop in 1993. As in earlier workshops, the central theme dealt with vehicle and duty schedulingproblems and the employment of operations-research-based software systems for operational planning in public transport. However, as was initiated in Hamburg in 1987, the scope of this workshop was broadened to include topics in related fields. this fundamental alteration was an inevitable consequence of the growing demand over the last decade for solutions to the complete planning process in public transport through integrated systems. therefore, the program of this workshop included sections which dealt withschedulingproblems and computerized systems for operational planning as well as sections on network planning and data management.
暂无评论