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Full-Text Articles in Mechanical Engineering

A Taxonomy Of Scheduling Problems In Semiconductor Device Test Operations, Tali Freed, Robert C. Leachman, Kenneth H. Doerr Apr 2002

A Taxonomy Of Scheduling Problems In Semiconductor Device Test Operations, Tali Freed, Robert C. Leachman, Kenneth H. Doerr

Industrial and Manufacturing Engineering

Semiconductor device test facilities differ not only by production volume and tester brands. The complexity of the devices and the characteristics of the testers affect the scheduling methodologies as well. Goals and strategies vary from one firm to another, leading to a variety of objectives and performance measures. Due to random yield lot size is variable and lot priorities are common. Changeover times are oftentimes sequence-dependent. Since semiconductor device testing systems are very costly, scheduling methods that increase the throughput of the facility are financially significant. In this paper we describe a variety of semiconductor device testing environments, develop mathematical ...


Generic Cost Estimation Framework For Design And Manufacturing Evaluation, Uday A. Kilkami Apr 2002

Generic Cost Estimation Framework For Design And Manufacturing Evaluation, Uday A. Kilkami

Mechanical & Aerospace Engineering Theses & Dissertations

A major drawback of current cost estimation models is their incapability of embracing effectively complete product development stage. Parametric estimation works well in early stages of design, but in detail design stage, a more complete estimation is provided by process model based and detail estimation techniques. A major paradigm shift is proposed in this work whereby ‘Cost’ is to be considered as a design parameter from scientific perspective, and it is to be treated as a design consequence rather than as an operational outcome. A comprehensive framework using System Analysis fundamentals is designed to study ‘Process Cost’ aspects of part ...


The Impact Of Fixturing Error On Feature Tolerance Allocation , Supapan Sangnui Jan 2002

The Impact Of Fixturing Error On Feature Tolerance Allocation , Supapan Sangnui

Retrospective Theses and Dissertations

Fixtures are used to locate, hold and support workpieces during the operation. An accuracy of the workpiece is decided by a relative location and orientation of the workpiece coordinate system with respect to that of the fixture. The impact of surface variability at contact points on the variability of workpiece location and orientation will be analyzed. Methods of estimating moments will be implemented to evaluate the distribution of the workpiece variability. When surface errors exist and the workpiece is fixtured for machining, inconsistency in feature location and orientation is expected. Hence, in order to derive efficient tolerance allocation for the ...


A New Analytical Evaluation Model For Kanban Controlled Systems With Fork/Join Synchronization Stations, Heedong Kim, Sarah M. Ryan Jan 2002

A New Analytical Evaluation Model For Kanban Controlled Systems With Fork/Join Synchronization Stations, Heedong Kim, Sarah M. Ryan

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

A nonlinear programming model is developed for analyzing the queuing model of a kanban controlled system with fork/join synchronization stations. The model finds the minimum number of kanbans for a given throughput requirement or the maximum throughput for a given number of kanbans, where servers have different exponential service times. Furthermore, it aids understanding of kanban systems.