ANALYSIS OF ELECTRONICS ASSEMBLY OPERATIONS:
LONGBOW HELLFIRE MISSILE POWER SUPPLY  
 
Kurt G. Springfield
John D. Hall
 
TASC, Inc.
700 Boulevard South, Suite 201
Huntsville, Alabama 35802, U.S.A.
  Gregg W. Bell
 
 
Northrop Grumman Corporation
Land Combat Systems - Huntsville
915 Explorer Boulevard
Huntsville, Alabama 35806, U.S.A.
 
ABSTRACT
 
This paper describes the use of discrete event simulation and design of experiments to analyze electronics assembly operations. A study was performed to determine if proposed changes to electronics assembly operations could achieve higher production throughput. This work supported the U.S. Army's Longbow HELLFIRE Missile program. The design of experiment used a modified orthogonal array containing both two and three-level factors. The authors describe the use of factor level average analysis to analyze experimental data. The Army used study results to assess risks in the program while the manufacturer gained information needed to improve the efficiency of its operations.
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DESIGN AND EVALUATION OF A SELECTIVE ASSEMBLY STATION FOR HIGH PRECISION SCROLL COMPRESSOR SHELLS  
 
  Arne Thesen
Akachai Jantayavichit
 
Department of Industrial Engineering
University of Wisconsin-Madison
1513 University Ave, Madison, WI 53706, U.S.A.
 
 
ABSTRACT
 
Certain automotive parts call for assemblies to be produced to tolerances that cannot be economically reached using standard high volume machining practices. Shims are used instead. We show that the required precision may be reached by using selective assembly. An efficient selective assembly system is proposed. Simulation is used to evaluate the performance of this system, and configurations capable of tolerance improvements of up to 1/20 are suggested.
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Integrating Discrete-Event Simulation with Statistical Process Control Charts for Transitions in a Manufacturing Environment  
 
  Harriet Black Nembhard
Ming-Shu Kao
Gino Lim

 
Department of Industrial Engineering
University of Wisconsin-Madison
Madison, WI 53706, U.S.A.
 
 
ABSTRACT
 
We present a model that integrates real-time process control charting with simulation modeling to illustrate the effects and benefits of SPC charts for quality improvement efforts. The integrated model is particularly significant in addressing transition issues arising from changes in the input material. A case study based on a medical manufacturing industry process is used to illustrate the approach.
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COMPARISON OF DISPATCHING RULES FOR SEMICONDUTOR MANUFACTURING USING LARGE FACILITY MODELS  
 
Manfred Mittler
 
IBM
Global Services - Industrial Sector
Decision Technology 0817/7103-47
D-70548 Stuttgart, GERMANY
  Alexander K. Schoemig
 
Infineon Technologies AG
Operational Excellence
P.O. Box 10 09 44
D-93009 Regensburg, GERMANY
 
ABSTRACT
 
In this paper, we present a comparison of five dispatching rules that aim to reduce the mean and the variance of cycle times. The performance of the dispatch rules is evaluated using simulation results for two large semiconductor wafer fabrication facilities. The results show that which dispatch rule achieves the best results depends on the fab, on the load of the fab and on the product.
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EVALUATION OF CLUSTER TOOL THROUGHPUT FOR THIN FILM HEAD PRODUCTION  
 
Eric J. Koehler
Timbur M. Wulf
Alvin C. Bruska
 
Wafer Systems Engineering
Seagate Technology
One Disc Drive
Bloomington, MN 55435, U.S.A.
  Marvin S. Seppanen
 
 
 
Production Systems of Winona, MN
2225 Garvin Heights Road
Winona, MN 55987, U.S.A.
 
ABSTRACT
 
This paper describes the application of simulation for analyzing cluster tool cycle times and cluster tool capacity planning. The objective of this project was to develop a flexible and expandable tool for rapidly calculating tool cycle times for a multiple step process through alternative tool configurations. The calculated process cycle times are then used to calculate equipment tool set requirements against product demand. The Seagate Industrial Engineering group utilized a simulation based cluster tool model developed to predict cluster tool cycle times and analyze cluster tool capacity across multiple tools and compare with results from static probability based model predictions.
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DETERMINING OPTIMAL LOT-SIZE FOR A SEMICONDUCTOR BACK-END FACTORY  
 
Juergen Potoradi
Gerald Winz
 
Infineon Technologies Asia Pacific
168 Kallang Way
SINGAPORE 349253
  Lee Weng Kam
 
 
Infineon Technologies (Integrated Circuit) Sdn Bhd
Free Trade Zone, Batu Berendam
Melaka, MALAYSIA
 
ABSTRACT
 
Modeling analysts are using a methodology that applies queuing theory logistics laws and simulation to factory performance analysis. These methods are being applied at semiconductor back-end factories, where a major focus is on achieving capacity increases with minimal equipment additions.
 
This paper describes this technical methodology and investigates an optimum lot-size for back-end factories based upon given throughput and cycle time targets. The analysis provides a recommended lot-size of 6800 for the overall production area, allowing the factory to maximize throughput while still meeting overall factory cycle time goals. The model indicates a potential 14% increase in throughput by selecting the optimal lot-size.
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OPTIMIZATION OF CYCLE TIME & UTILIZATION IN SEMICONDUCTOR TEST MANUFACTURING USING SIMULATION BASED, ON-LINE NEAR-REAL-TIME SCHEDULING SYSTEM  
 
  Appa Iyer Sivakumar
 
Gintic Institute of Manufacturing Technology
Nanyang Technological University
71 Nanyang Drive, 638075, SINGAPORE
 
 
ABSTRACT
 
A discrete event simulation based "on-line near-real-time" dynamic scheduling and optimization system has been conceptualized, designed, and developed to optimize cycle time and asset utilization in the complex manufacturing environment of semiconductor test manufacturing. Our approach includes the application of rules and optimization algorithm, using multiple variables as an integral part of discrete event simulation of the manufacturing operation and auto simulation model generation at a desired frequency. The system has been implemented at a semiconductor back-end site. The impact of the system includes the achievement of world class cycle time, improved machine utilization, reduction in the time that planners and manufacturing personnel spend on scheduling, and more predictable and highly repeatable manufacturing performance. In addition it enables managers and senior planners to carry out "what if" analysis to plan for future.
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Use of Dynamic Simulation to Analyze Storage and Retrieval Strategies  
 
Mark A. Kosfeld
 
Intel Corporation
Building C11-110
6505 West Chandler Boulevard
Chandler, Arizona 85226-3324, U.S.A.
  Timothy D. Quinn
 
Intel Corporation
Building CH3-84
5000 West Chandler Boulevard
Chandler, Arizona 85226-3324, U.S.A
 
ABSTRACT
 
In the second half of 1998, shipment volumes at one of Intel's warehouses had increased beyond the storage and retrieval capabilities of the facility. An engineering improvement team began studying changes to the Warehouse Management System (WMS) that would increase throughput. From observation it was unclear what WMS code changes would actually improve throughput, and nearly impossible to predict the amount of improvement that would be realized in the facility. To solve these issues, the algorithms for storing product, releasing orders, and routing vehicles were first analyzed in a dynamic simulation model. Strategies that showed a significant increase in throughput were recommended for coding into the WMS software. Using a simulation model not only allowed the strategies to be prioritized, but also predicted the performance of each strategy.
 
The equipment and physical layout of the facility were comprehended in the simulation model. The storage area consisted of twelve aisles, each 112 bins long and 16 bins high. Product was stored in boxes, which were retrieved and stored by operators driving Stockpicker vehicles. Since both the storage and retrieval of material were entirely controlled by the WMS, it was imperative that a logical routing decision for each Stockpicker vehicle be made.
 
The initial storage and retrieval strategies were first coded in the simulation model to ensure that the model outputs were valid. Then, numerous storage and retrieval strategies were coded and analyzed to determine which ones would increase throughput.
 
The final simulation results showed that throughput could be increased by 110% per day by simply improving the WMS storage and retrieval strategies. No additional vehicles or headcount were required which resulted in a significant annual cost savings.
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A SIMULATION MODEL TO STUDY THE DYNAMICS IN A SERVICE-ORIENTED SUPPLY CHAIN  
 
Edward G. Anderson
 
Management Department
CBA 4.202
The University of Texas at Austin
Austin, Texas 78712
  Douglas J. Morrice
 
MSIS Department
CBA 5.202
The University of Texas at Austin
Austin, Texas 78712
 
ABSTRACT
 
In this paper, we investigate the dynamic behavior of a simple service-oriented supply chain in the presence of non-stationary demand using simulation. The supply chain contains four stages in series. Each stage holds no finished goods inventory. Rather, the order backlog can only be managed by adjusting capacity. These conditions reflect the reality of many service (and custom manufacturing) supply chains. The simulation model is used to compare various capacity management strategies. Measures of performance include application completion rate, backlog levels, and total cumulative costs.
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Increasing the Power and Value of Manufacturing Simulation via Collaboration with Other Analytical Tools: A Panel Discussion  
 
Onur M. Ülgen
 
Production Modeling Corporation and Industrial & Manufacturing Systems Department
University of Michigan
Dearborn, MI 48128, USA
John Shore
 
Production Modeling Corporation
Three Parklane Boulevard, Suite 1006W
Dearborn, MI 48126, USA
Gene Coffman
 
Ford Motor Company
Advanced Manufacturing Technology Development
24500 Glendale Avenue,
Redford, MI 48239, USA
 
 
David Sly
 
Engineering Animation, Inc.
VP Factory Products
2321 North Loop Drive
Ames, Iowa 50010, USA
 
 
Matt Rohrer
 
AutoSimulstions
655 Medical Drive
Bountiful, Utah 84010, USA
 
 
Demet Wood
 
General Motors
NA Quality, Reliability & Comp. Oper. Impl.
31 E Judson St., 2nd Floor
Pontiac, MI 48342, USA
 
ABSTRACT
 
The objective of this panel session is to describe how and when should manufacturing simulation practitioners add to the value of projects by interfacing simulation analyses with other analyses such as optimization, layout/material flow, scheduling, robotic, and queuing. The panelists will discuss how each analytical tool adds value to the discrete-event manufacturing simulation, when in the life cycle of a project it should be brought in, what are the main advantages and disadvantages of bringing in the additional tools, managing and selling collaborative analyses projects, and training requirements for collaborative analyses.
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ANCILLARY EFFECTS OF SIMULATION  
 
Matt Hickie
 
MOS 12 Die Manufacturing Motorola
1300 North Alma School Road, Mail Drop CH 305
Chandler, AZ, 85224, U.S.A.
  John W. Fowler, Ph.D.
 
Industrial Engineering
Arizona State University
Tempe, AZ, 85287-5906, U.S.A.
 
ABSTRACT
 
Simulation can often be one of the first modeling tools implemented at a manufacturing site. When this occurs, much effort must be used to get current manufacturing data into the simulation model. The amount of time and data needed to get the simulation running to an acceptable validation level and to maintain that validation level over time, should lead to an effort to automate the loading of factory data into simulation. If this automation effort is efficient and comprehensive, it can become the cornerstone of a system that benefits manufacturing from more than just simulation analysis. The other benefits range from the development of a simple times theoretical analysis of the line to the complex development of an infinite capacity planning system. This paper will discuss a real world example of the extra benefits received from implementing simulation at a semiconductor manufacturing plant.
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VALIDATING A MANUFACTURING PARADIGM: A SYSTEM DYNAMICS MODELING APPROACH  
 
  Richard A. Reid
Elsa L. Koljonen
 
Anderson Schools of Management
University of New Mexico
Albuquerque, NM 87131, U.S.A.
 
 
ABSTRACT
 
Logic tools from the Theory of Constraints (TOC) provide the ability to descriptively characterize the entity relationships responsible for a typical, although somewhat chaotic, manufacturing environment. Basically through one-to-one mappings, System Dynamics (SD) models are created from the TOC logic diagrams. Insights gained from exercising the SD models are used to establish a new managerial conceptual framework. This structure guides managers through the continuous improvement process relative to addressing either a physical, policy, or paradigm constraint in their production system.
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SIMULATION AS A TOOL FOR CONTINUOUS PROCESS IMPROVEMENT  
 
  Mel Adams
Paul Componation
Hank Czarnecki
Bernard J. Schroer
 
University of Alabama in Huntsville
Huntsville, AL 35899, U.S.A.
 
 
ABSTRACT
 
Simulation offers a powerful tool to support the continuous improvement process. This paper presents a description of the tools of lean manufacturing, the steps in the continuous improvement process and two case studies where simulation was used in the continuous improvement.
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A COMPARISON OF THE EXPONENTIAL AND THE HYPEREXPONENTIAL DISTRIBUTIONS FOR MODELING MOVE REQUESTS IN A SEMICONDUCTOR FAB  
 
Siroos Sokhan-Sanj
Gabriel Gaxiola
 
PRI Automation, Inc.
Automation Planning and Design
1250 S. Clearview Ave. #104
Mesa, Arizona 85208, USA
  Gerald T. Mackulak, Ph.D.
Fredrik B. Malmgren
 
Department of Industrial Engineering
Arizona State University
Tempe, Arizona 85287-5906, USA
 
ABSTRACT
 
Variability in any manufacturing process negatively impacts performance since it leads to system disruption. Semiconductor manufacturing, with its characteristic reentrant flow, typically experiences extreme variability. The Automated Material Handling System (AMHS) in a semiconductor fab is subject to this variability and yet must still complete deliveries within a specified time limit. When designing the AMHS the variability used in the simulation model will have a direct impact on the equipment set selected. Sizing a system based on the average case scenario creates a system incapable of meeting the extreme conditions often encountered in reality. The challenge for the modeler of a semiconductor fab is to accurately represent this variability. This paper discusses how the hyperexponential distribution more accurately represents the variability in semiconductor fabs than the typically used exponential distribution.
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REDUCING MODEL CREATION CYCLE TIME BY AUTOMATED CONVERSION OF A CAD AMHS LAYOUT DESIGN  
 
Igor Paprotny
 
Automation Planning and Design Group  PRI Automation, Inc.  Mesa, Arizona 85208, USA
Wendy Zhao
 
Software Division
PRI Automation, Inc.
Billerica, MA 01821. USA
Gerald Mackulak, Ph.D.
 
Department. of Industrial Engineering
Arizona State University
Tempe, Arizona 85287-5906, USA
 
ABSTRACT
 
Simulation is a popular tool for accurately estimating the performance of an automated material handling system (AMHS). Accuracy of the model is normally dependent on a detailed description of the AMHS physical system components and their coordinate positions. In this paper, a methodology is defined for automatically inputting the physical system components used to describe an AMHS within a simulation language. The method is based on data extraction from a CAD layout file of the system. Automatically generating the physical system components reduces simulation model building time and increases model accuracy.
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INCREASING FIRST PASS ACCURACY OF AMHS SIMULATION OUTPUT USING LEGACY DATA  
 
Scott Wu
John Rayter
Igor Paprotny
 
Automation Planning and Design Group
PRI Automation, Inc.
Mesa, Arizona 85208, USA
  Gerald Mackulak, Ph.D.
Joakim Yngve
 
 
Department Of Industrial Engineering
Arizona State University
Tempe, Arizona 85287-5906, USA
 
ABSTRACT
 
The operating characteristics of wafer production facilities are extremely dynamic, driven by short product life cycles, rapid equipment obsolescence and recurring layout expansion. These factors also have an impact on the design of the Automated Material Handling System (AMHS). The AMHS must be able to react and accept change as rapidly as the production process dictates. The AMHS design engineer faces a significant challenge in that modeling efforts must be proactive and anticipate the long-term requirements of a given facility.
 
There are, of course, several methods available for addressing this issue. This paper will point out the limitations to these methods when applied to AMHS modeling and propose an alternative. Specifically, behavioral trends from historical data can be exploited when appropriate. Simulation results from legacy designs may prove to be an efficient indicator of the validity of new designs.
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DEVELOPMENT OF A SIMULATION MODEL FOR AN ARMY CHEMICAL MUNITION DISPOSAL FACILITY  
 
Michael A. Berger
Jiuyi Hua
Paul T. Otis
Katrina S. Werpetinski
 
Mitretek Systems, Inc.
7525 Colshire Drive
McLean, VA, 22102-7400, U.S.A.
  Vincent F. Johnston
 
 
 
 
U.S. Army Program Manager for Chemical Demilitarization
Attn: SFAE-CD-CO-O
Aberdeen Proving Ground, MD 21010-5401, U.S.A.
 
ABSTRACT
 
The U.S. Army is in the process of disposing of its stockpile of obsolete chemical weapons. A simulation model has been developed to help identify facility operational strategies that may increase the number of munitions or the quantity of chemical agent processed over an extended period of time. It is also used to assess the potential effects of proposed plant modifications and alternative process configurations on plant performance, schedule, and operating costs prior to their implementation. A new customized graphical user interface to the simulation model has been developed to overcome software limitations and enhance the model system. This allows more rapid and complete assessments by a variety of users at different facilities.
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Interface Driven Domain-Independent Modeling Architecture for "Soft-Commissioning" and "Reality in the Loop"  
 
  Franz Auinger
Markus Vorderwinkler
Georg Buchtela
 
PROFACTOR Produktionsforschungs GmbH
Wehrgrabengasse 1-5, A-4400 Steyr, Austria
 
 
ABSTRACT
 
As industrial manufacturing and automation systems grow in complexity, there is a need for control software engineering support. Soft-Commissioning and Reality in the Loop (RIL) are two novel approaches which allow coupling simulation models to real world entities and allow the analyst to pre-commission and test the behavior of a system, before it is completely built in reality. To be flexible and fast in building up a simulation model fulfilling the requirements of Soft-Commissioning and RIL there is a need for a component-based modeling architecture. In this paper we define the characteristic requirements, and derive an architecture out of them, which is discussed from different aspects. Finally we briefly present a simple example.
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SIMULATION OPTIMIZATION WITH THE LINEAR MOVE AND EXCHANGE MOVE OPTIMIZATION ALGORITHM  
 
Marcos Ribeiro Pereira Barretto
Leonardo Chwif
 
Mechatronics Lab
University of São Paulo
Av. Prof. Mello Moraes 2231
Sao Paulo, 05508-900, BRAZIL
   
Tillal Eldabi
Ray J. Paul
 
Centre For Applied Simulation Modelling
Department Of Information Systems And Computing
Brunel University
Uxbridge, Middlesex, UB8 3PH, U.K.
 
ABSTRACT
 
The Linear Move and Exchange Move Optimization (LEO) is an algorithm based on a simulated annealing algorithm (SA), a relatively recent algorithm for solving hard combinatorial optimization problems. The LEO algorithm was successfully applied to a facility layout problem, a scheduling problem and a line balancing problem. In this paper we will try to apply the LEO algorithm to the problem of optimizing a manufacturing simulation model, based on a Steelworks Plant. This paper also demonstrates the effectiveness and versatility of this algorithm. We compare the search effort of this algorithm with a Genetic Algorithm (GA) implementation of the same problem.
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