No description available.

Proefschrift Universiteit van Amsterdam. / Auters namen op de omslag: Henk-Jan Ramaker en Eric van Sprang. Met bibliogr., lit. opg. - Met samenvatting in het Nederlands.

International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Boeing's Test Data Retrieval System not only acts as an interface between the Airborne Data Acquisition System and a mainframe computer but also does batch mode processing of data at faster than real time. Analysis engineers request time intervals and measurements of interest. Time intervals and measurements requested are acquired from the flight tape, converted to first order engineering units, and output to 3480 data cartridge tape for post processing. This allows all test data to be stored and only the data of interest to be processed at any given time.

This research aims at a study of the hybrid flow shop problem which has parallel batch-processing machines in one stage and discrete-processing machines in other stages to process jobs of arbitrary sizes. The objective is to minimize the makespan for a set of jobs. The problem is denoted as: FF|batch1, sj|Cmax. The problem is formulated as a mixed-integer linear program. The commercial solver, AMPL/CPLEX, is used to solve problem instances to their optimality. Experimental results show that AMPL/CPLEX requires considerable time to find the optimal solution for even a small size problem, i.e., a 6-job instance requires 2 hours in average. A bottleneck-first-decomposition heuristic (BFD) is proposed in this study to overcome the computational (time) problem encountered while using the commercial solver. The proposed BFD heuristic is inspired by the shifting bottleneck heuristic. It decomposes the entire problem into three sub-problems, and schedules the sub-problems one by one. The proposed BFD heuristic consists of four major steps: formulating sub-problems, prioritizing sub-problems, solving sub-problems and re-scheduling. For solving the sub-problems, two heuristic algorithms are proposed; one for scheduling a hybrid flow shop with discrete processing machines, and the other for scheduling parallel batching machines (single stage). Both consider job arrival and delivery times. An experiment design is conducted to evaluate the effectiveness of the proposed BFD, which is further evaluated against a set of common heuristics including a randomized greedy heuristic and five dispatching rules. The results show that the proposed BFD heuristic outperforms all these algorithms. To evaluate the quality of the heuristic solution, a procedure is developed to calculate a lower bound of makespan for the problem under study. The lower bound obtained is tighter than other bounds developed for related problems in literature. A meta-search approach based on the Genetic Algorithm concept is developed to evaluate the significance of further improving the solution obtained from the proposed BFD heuristic. The experiment indicates that it reduces the makespan by 1.93% in average within a negligible time when problem size is less than 50 jobs.

Batch processing is a means of improving the efficiency of transaction processing systems. Despite the maturity of this field, there is no rigorous theory that can assist in the design of batch systems. This thesis proposes such a theory, and shows that it is practical to use it to automate system design. This has important consequences; the main impediment to the wider use of batch systems is the high cost of their development and intenance. The theory is developed twice: informally, in a way that can be used by a systems analyst, and formally, as a result of which a computer program has been developed to prove the feasibility of automated design. Two important concepts are identified, which can aid in the decomposition of any system: 'separability', and 'independence'. Separability is the property that allows processes to be joined together by pipelines or similar topologies. Independence is the property that allows elements of a large set to be accessed and updated independently of one another. Traditional batch processing technology exploits independence when it uses sequential access in preference to random access. It is shown how the same property allows parallel access, resulting in speed gains limited only by the number of processors. This is a useful development that should assist in the design of very high throughput transaction processing systems. Systems are specified procedurally by describing an ideal system, which generates output and updates its internal state immediately following each input event. The derived systems have the same external behaviour as the ideal system except that their outputs and internal states lag those of the ideal system arbitrarily. Indeed, their state variables may have different delays, and the systems as whole may never be in consistent state. A 'state dependency graph' is derived from a static analysis of a specification. The reduced graph of its strongly-connected components defines a canonical process network from which all possible implementations of the system can be derived by composition. From these it is possible to choose the one that minimises any imposed cost function. Although, in general, choosing the optimum design proves to be an NP-complete problem, it is shown that heuristics can find it quickly in practical cases. / Thesis (Ph.D.)--Mathematical and Computer Sciences (Department of Computer Science), 1999.

No description available.

No description available.

Batch processing is a means of improving the efficiency of transaction processing systems. Despite the maturity of this field, there is no rigorous theory that can assist in the design of batch systems. This thesis proposes such a theory, and shows that it is practical to use it to automate system design. This has important consequences; the main impediment to the wider use of batch systems is the high cost of their development and intenance. The theory is developed twice: informally, in a way that can be used by a systems analyst, and formally, as a result of which a computer program has been developed to prove the feasibility of automated design. Two important concepts are identified, which can aid in the decomposition of any system: 'separability', and 'independence'. Separability is the property that allows processes to be joined together by pipelines or similar topologies. Independence is the property that allows elements of a large set to be accessed and updated independently of one another. Traditional batch processing technology exploits independence when it uses sequential access in preference to random access. It is shown how the same property allows parallel access, resulting in speed gains limited only by the number of processors. This is a useful development that should assist in the design of very high throughput transaction processing systems. Systems are specified procedurally by describing an ideal system, which generates output and updates its internal state immediately following each input event. The derived systems have the same external behaviour as the ideal system except that their outputs and internal states lag those of the ideal system arbitrarily. Indeed, their state variables may have different delays, and the systems as whole may never be in consistent state. A 'state dependency graph' is derived from a static analysis of a specification. The reduced graph of its strongly-connected components defines a canonical process network from which all possible implementations of the system can be derived by composition. From these it is possible to choose the one that minimises any imposed cost function. Although, in general, choosing the optimum design proves to be an NP-complete problem, it is shown that heuristics can find it quickly in practical cases. / Thesis (Ph.D.)--Mathematical and Computer Sciences (Department of Computer Science), 1999.

No description available.

No description available.