Real-world scheduling is decision making under vague constraints of diierent importance, often using uncertain data, where compromises between antagonistic criteria are allowed. We explain in theory and by detailed examples a new combination of fuzzy set based constraints and repair based heuristics that help to model these scheduling problems. We simplify the mathematics needed for a method of...

In this paper a new artificial immune system (AIS) algorithm is proposed to solve multi objective fuzzy flow shop scheduling problems. A new mutation operator is also described for this AIS. Fuzzy sets are used to model processing times and due dates. The objectives are to minimize the average tardiness and the number of tardy jobs. The developed new AIS algorithm is tested on real world data c...

In Round Robin CPU scheduling algorithm the main concern is with the size of time quantum and the increased waiting and turnaround time. Decision for these is usually based on parameters which are assumed to be precise. However, in many cases the values of these parameters are vague and imprecise. The performance of fuzzy logic depends upon the ability to deal with Linguistic variables. With th...

In hard real-time systems, tasks have to be performed not only correctly, but also in a timely fashion. If timing constraints are not met, there might be severe consequences. Task scheduling is the most important problem in designing a hard real-time system, because the scheduling algorithm ensures that tasks meet their deadlines. However, the inherit nature of uncertainty in dynamic hard real-...

Considerable research has been done in order to schedule tasks to a multiple processing systems. Some of the computation time of these tasks may, however, be imprecise due to the nature of the problem. In this paper, an imprecise task graph is used to model the problem where each node represents a task associated with its computation time. An algorithm, called rotation scheduling, is extended t...

We present a modification of the vehicle routing problem with the additional restriction that time windows are associated with each customer by defining an interval wherein the customer has to be supplied. We introduce a two phase strategy of this vehicle routing and scheduling problem with time windows using fuzzy logic to realize inference steps in fuzzy if-then rule bases.

Changes in operating conditions can alter performances of nonlinear processes controlled with a fixed PID algorithm. One way of preventing degradation is to develop a supervised control system. In this paper we present some results about fuzzy gain scheduling of a double PID controller for stabilization of an inverted pendulum on a cart. First, on the basis of the responses obtained with an uns...

In order to achieve the goal of fully automated manufacturing systems, novel techniques and tools in many aspects of manufacturing, including scheduling and control, need to be developed. These novel techniques can be recognised by their capabilities to adapt to complex situations, which conventional approaches have not as yet been able to handle properly. This paper proposes a new approach to ...

The quality of control (QoC) of a resource-constrained embedded control system may be jeopardized in dynamic environments with variable workload. This gives rise to the increasing demand of co-design of control and scheduling. To deal with uncertainties in resource availability, a fuzzy feedback scheduling (FFS) scheme is proposed in this paper. Within the framework of feedback scheduling, the ...

This paper presents the application of fuzzy set theory (FST) within the context of integrated planning and scheduling. Fuzzy set theory provides a framework for modelling uncertain or ambiguous information, which is commonly encountered in industry. A typical example of a r l i a p e t s d p c s ©