The local search technique has become a widely used tool for solving many combinatorial optimization problems. In the case of the job-shop the implementation of such a technique is not ...straightforward at all due to the existence of the technological constraints among the operations that belong to the same job. Their presence renders a certain set of schedules infeasible. Consequently, special attention is required when defining optimization algorithms to prevent the possibility of reaching an infeasible schedule during execution. Traditionally, the problem is tackled on the neighborhood level by using only a limited set of moves for which feasibility inherently holds. This paper proposes an alternative way to avoid infeasibility by incorporating a repairing technique into the mechanism for applying moves to a schedule. Whenever an infeasible move is being applied, a repairing mechanism rearranges the underlying schedule in such a way that the feasibility of the move is restored. The possibility of reaching infeasible solutions is, therefore, eliminated on the lowest possible conceptual level. Consequently, neighborhood functions need not to be constrained to a limited set of feasible moves any more.
Investigations of functional electrical stimulation (FES) of the closing muscles in the lower urinary tract using nonimplantable electrical stimulators have reached the final stage. The optimal ...stimuli parameters were chosen on the basis of neurophysiological studies of the urinary tract and urodynamic measurements of mechanical response to electrical stimulation. According to these findings, two electronic systems for FES have been developed. An adjustable system for stimulation of the urethral closing mechanism using vaginal or anal plugs. The external unit of the stimulator contains a generator producing square-wave pulses. The vaginal and anal plugs are from Vitalograph Ltd, and Cardiac Recorders Ltd., commercial tipes redesigned to suit our needs. Frequency and duration of the pulses can be individually adjusted for each patient. An automatic integrated adjustable system for stimulation of the urethral closing mechanism built into a vaginal plug. This stimulator is based on completely new design principles. It has the form of a cylinder with hemispherical ends. Both the electronic unit and battery supply are located within. The system is completely automatic and is started by placing the stimulator in the vagina. Both systems mentioned were constructed for curing stress incontinence, post-operative incontinence, enuresis and in some cases for use in incontinent paraplegics. Clinical evaluation has given satisfactory results for both types of stimulators in the above-mentioned patients. They are simple to use and instructions can be given in an urologist's prescription. Permanent or intermittent application is possible.
Urethral and bladder responses to anal electrical stimulation were evaluated by cystometry and urethral pressure profile measurements in 55 patients with different urethral-bladder dysfunctions. In ...50 per cent of the patients examined the electrical stimulation caused normal reciprocal response, that is bladder inhibition with urethral contraction. In other patients the electrical stimulation caused almost all other possible bladder and urethral responses.