We consider the control of a batchprocessing machine which is part of a larger manufacturing network of machines. Systems consisting of a batchprocessing machine and one or more unit-capacity machines in tandem are ...
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We consider the control of a batchprocessing machine which is part of a larger manufacturing network of machines. Systems consisting of a batchprocessing machine and one or more unit-capacity machines in tandem are considered. The objective is to minimize the average time that jobs spend in the entire system. We present algorithms to determine the optimal policies for certain finite horizon, deterministic problems. We then discuss the structure of the optimal policies for infinite horizon, stochastic problems, and investigate the benefit of utilizing information about upstream and downstream unit-capacity machines in the control of the batch machine. We develop a simple heuristic scheduling policy to control the batch machine which takes into account the state of other machines in the network. Computational results demonstrate the effectiveness of our heuristic over a wide range of problem instances.
This study focuses on the N-level batching problem with a hierarchical clustering structure. Clustering is the task of grouping a set of item types in such a way that item types in the same cluster are more similar (i...
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This study focuses on the N-level batching problem with a hierarchical clustering structure. Clustering is the task of grouping a set of item types in such a way that item types in the same cluster are more similar (in some sense or another) to each other than to those in other clusters. In hierarchical clustering structure, more and more different item types are clustered together as the level of the hierarchy increases. N-level batching is the process by which items with different types are grouped into several batches passed from level 1 to level N sequentially for given hierarchical clustering structure such that batches in each level should satisfy the maximum and minimum batch size requirements of the level. We consider two types of processing costs of the batches: unit processing cost and batchprocessing cost. We formulate the N-level batching problem with a hierarchical clustering structure as a nonlinear integer programming model with the objective of minimizing the total processing cost. To solve the problem optimally, we propose a multidimensional dynamic programming algorithm with an example.
We develop an Optimized Queueing Network (OQNet) capacity planning tool for supporting the design of new and reconfigured semiconductor fabrication facilities that makes use of queueing network approximations and an o...
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We develop an Optimized Queueing Network (OQNet) capacity planning tool for supporting the design of new and reconfigured semiconductor fabrication facilities that makes use of queueing network approximations and an optimization routine. The basic problem addressed by this tool is to minimize the facility cost required to meet specified volume and cycle time targets. Features common to semiconductor environments, such as batch processes, re-entrant flows, multiple product classes, and machine setups, are incorporated into the model. Comparisons with simulation show that the queueing and other approximations are reasonably accurate. Tests of the optimization routine demonstrate that it can find good solutions quickly.
In this paper, we investigate the unbounded version of scheduling jobs with release dates and deadlines on a batchprocessing machine. NP-completeness is established for the case where all jobs have agreeable processi...
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In this paper, we investigate the unbounded version of scheduling jobs with release dates and deadlines on a batchprocessing machine. NP-completeness is established for the case where all jobs have agreeable processing times and deadlines. Polynomial time algorithms are presented for the following cases: agreeable release dates and deadlines;agreeable release dates and processing times;a fixed number of distinct release dates, distinct processing times or distinct deadlines.
Presents empirical distributions of program lengths, execution times, processing times, and loading times of over 10,000 jobs serviced in a university computing center environment in Michigan. Characteristics of a spe...
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Presents empirical distributions of program lengths, execution times, processing times, and loading times of over 10,000 jobs serviced in a university computing center environment in Michigan. Characteristics of a specific batch-processing system; Dependence of the time variables on the program lengths of jobs; Distinction between successful and unsuccessful jobs using statistics.
A study of the programming efforts of students in an introductory programming course is presented and the effects of having instant turnaround (a few minutes) as opposed to conventional batchprocessing with turnaroun...
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A study of the programming efforts of students in an introductory programming course is presented and the effects of having instant turnaround (a few minutes) as opposed to conventional batchprocessing with turnaround times of a few hours are examined. Among the items compared are the number of computer runs per trip to the computation center, program preparation time, keypunching time, debugging time, number of runs, and elapsed time from the first run to the last run on each problem. Even though the results are influenced by the fact that 'bonus points' were given for completion of a programming problem in less than a specified number of runs, there is evidence to support 'Instant' over 'batch'. [ABSTRACT FROM AUTHOR]
Body odor isn't pleasant, but most people rarely have to smell it thanks toUnilever's personal care products plant (Rae ford, NC), which has 600 employees and runs a 24/7operation. Faced with a required reloca...
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Body odor isn't pleasant, but most people rarely have to smell it thanks toUnilever's personal care products plant (Rae ford, NC), which has 600 employees and runs a 24/7operation. Faced with a required relocation, consolidation and upgrade of its deodorant application,the 72-year-old company recently implemented Rockwell Automation's (Milwaukee, WI) batch managementsoftware and used its Global Manufacturing Solutions (GMS) group to help meet timetomarket andproduction demands, and save USD300,000 in engineering costs. Unilever's deodorant operationpreviously used a costly and inefficient manual approach. The company evaluated several batch andcontrol system options, but "previous work with Rockwell's RSBizWare batchbatch management softwareat our facility in Clinton, CT, impressed our team," says Randy Carter, Unilever's senior controlsengineer. "We were also impressed with Rockwell's integrated architecture and demonstrated effort toemploy batch mobility and standardization concepts through ISA S88."
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