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Performance Evaluation of Warehouses with Automated Storage and Retrieval Technologies University of Louisville ThinkIR: The University of Louisville's Institutional Repository Electronic Theses and Dissertations 8-2010 Performance evaluation of warehouses with automated storage and retrieval technologies. Xiao Cai University of Louisville Follow this and additional works at: https://ir.library.louisville.edu/etd Recommended Citation Cai, Xiao, "Performance evaluation of warehouses with automated storage and retrieval technologies." (2010). Electronic Theses and Dissertations. Paper 195. https://doi.org/10.18297/etd/195 This Doctoral Dissertation is brought to you for free and open access by ThinkIR: The University of Louisville's Institutional Repository. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of ThinkIR: The University of Louisville's Institutional Repository. This title appears here courtesy of the author, who has retained all other copyrights. For more information, please contact [email protected]. PERFORMANCE EVALUATION OF WAREHOUSES WITH AUTOMATED STORAGE AND RETRIEVAL TECHNOLOGIES By Xiao Cai B.E., Huazhong University of Science and Technology, 2005 M.S., University of Louisville, 2007 A Dissertation Submitted to the Faculty of the Graduate School of the University of Louisville in Partial Fulfillment of the R.equirements for the Doctor of Philosophy Department of Industrial Engineering University of Louisville Louit:lville, Kentucky Augest 2010 © Copyright 2010 by Xiao Cai All rights reserved PERFORMANCE EVALUATION OF WAREHOUSES WITH AUTOMATED STORAGE AND RETRIEVAL TECHNOLOGIES By Xiao Cai B.E., Huazhong University of Science and Technology, 2005 M.S., University of Louisville, 2007 A Dissertation Approved on July 8th, 2010 by the following Dissertation Committee: Dissertation Director 11 DEDICATION This dissertation is dedicated to my parents Mr. Jiang Cai and Mrs. Meijuan Zhang who have given me invaluable educational opportunities. III ACKNOWLEDGMENTS I would like to thank my major professor, Dr. Sunderesh Heragu, for his guidance and patience. I would also like to thank the other committee members, Dr. Suraj Alexander, Dr. William Biles, Dr. Gerald Evans and Dr. Thomas Riedel, for their comments and assistance over the past four years. I would also like to express my thanks to the Department of Industrial Engineering for all the support they provided me for the past four years. I wish to also acknowledge the love and support of my parents, Jiang Cai and Meijuan Zhang for letting me pursue my education. Lastly, I would like to thank my friends here and in China to support me during these years. iv ABSTRACT PERFORMANCE EVALUATION OF WAREHOUSES WITH AUTOMATED STORAGE AND RETRIEVAL TECHNOLOGIES Xiao Cai July 8th, 2010 In this dissertation, we study the performance evaluation of two automated warehouse material handling (MH) technologies - automated storage/retrieval system (AS/RS) and autonomous vehicle storage/retrieval system (AVS/RS). AS/RS is a traditional automated warehouse MH technology and has been used for more than five decades. AVS/RS is a relatively new automated warehouse MH technology and an alternative to AS/RS. There are two possible configurations of AVS/RS: AVS/RS with tier­ captive vehicles and AVS/RS with tier-to-tier vehicles. We model the AS/RS and both configurations of the AVS/RS as queueing networks. We analyze and develop approximate algorithms for these network models and use them to estimate perfor­ mance of the two automated warehouse MH technologies. Chapter 2 contains two parts. The first part is a brief review of existing papers about AS/RS and AVS/RS. The second part is a methodological review of queueing network theory, which serves as a building block for our study. In Chapter 3, we model AS/RSs and AVS/RSs with tier-captive vehicles as open queueing networks (OQNs). We show how to analyze OQNs and estimate related performance measures. We then apply an existing OQN analyzer to compare the two MH technologies and answer various design questions. v In Chapter 4 and Chapter 5, we present some efficient algorithms to solve SOQN. We show how to model AVSjRSs with tier-to-tier vehicles as SOQNs and evaluate performance of these designs in Chapter 6. AVSjRS is a relatively new automated warehouse design technology. Hence, there are few efficient analytical tools to evaluate performance mea.<;ures of this technology. We developed some efficient algorithms based on SOQN to quickly and effectively evaluate performance of AVSjRS. Additionally, we present a tool that helps a ware­ house designer during the concepting stage to determine the type of MH technology to use, analyze numerous alternate warehouse configurations and select one of these for final implementation. VI TABLE OF CONTENTS ABSTRACT ................................................................... v LIST OF TABLES. x LIST OF FIGURES ............................................................ xiii CHAPTER 1. INTRODUCTION. 1 1.1. Automated MH technologies in warehouses. 1 1.2. Introduction of AS/RS and AVS/RS. ...... ....... ..................... 2 1.3. Queueing Network Theory............................... .............. 5 1.4. Aim and overview. 7 CHAPTER 2. LITERATURE REVIEW. 9 2.1. Introduction. 9 2.2. AS/RS literature review. 9 2.3. AVS/RS literature review.... .. .. .. ... ... .. ... .. .. .. ... .. 15 2.4. Introduction of queueing network theory. .. .. .. .. .. .. .. .. .. 16 2.5. OQN methodology review .............................................. 25 2.6. CQN methodology review .............................................. 34 2.7. SOQN methodology review........................... ................. 43 CHAPTER 3. PERFORMANCE EVALUATION OF AS/RS AND AVS/RS WITH TIER-CAPTIVE VEHICLES. .. 49 3.1. Introduction. .. 49 3.2. A comparison of AS/RS and AVS/RS .................................. 50 vii 3.3. Application of analytical open queueing network model for analyzing ASjRS and AVSjRS with tier-captive vehicles. .. .. .. .. .. .. .. .. 51 3.4. Use of analytical models for warehouse design conceptualization. .. .. 55 3.5. Conclusions. .. 77 CHAPTER 4. PERFORMANCE EVALUATION OF SINGLE-CLASS SOQN. 79 4.1. Introduction........................................................... 79 4.2. SOQN notation ........................................................ 80 4.3. Single-class SOQN with two stages of exponential servers and Poisson arrivals . .. 81 4.4. Single-class SOQN with multiple stages of exponential servers and Poisson arrivals. .. 93 4.5. Conclusions............................................................ 95 CHAPTER 5. PERFORMANCE EVALUATION OF GENERALIZED SOQN 97 5.1. Introduction. .. 97 5.2. Phase-type distributions. .. 97 5.3. Single-class SOQN with two stages of general servers and general arrivals 108 5.4. Single-class SOQN with multiple stages of general servers and general arrivals ................................................................ 122 5.5. Multi-class SOQN with multiple stages of general servers and general arrivals ................................................................ 125 5.6. Conclusions ............................................................ 135 CHAPTER 6. MODEL THE AVSjRS WITH TIER-TO-TIER VEHICLES AS AN SOQN ..................................................... 137 6.1. Introduction ........................................................... 137 6.2. Modeling the AVSjRS as an SOQN .................................... 137 viii 6.3. Discussion of synchronization process policies. .. 145 6.4. Numerical experiments ................................................. 149 6.5. Conclusions ............................................................ 156 CHAPTER 7. SUMMARy ................................................... 158 7.1. Conclusions ............................................................ 158 7.2. Future research plan ................................................... 159 REFERENCES ................................................................ 161 CURRICULUM VITAE ........................................................ 172 ix LIST OF TABLES 3.1 A VSIRS rack system data ..................................................................... 56 3.2 Autonomous vehicle data ..................................................................... 56 3.3 Lift data .......................................................................................... 56 3.4 Pallet data ....................................................................................... 57 3.5 trl under different conditions .................................................................. 63 3.6 ASIRS rack system data ....................................................................... 66 3.7 ASIRS automated devices data ............................................................... 67 3.8 AVSIRS parameters ........................................................................... 71 3.9 Different throughput requirements (AVSIRS) ............................................. 72 3.10 ASIRS parameters ............................................................................ 72 3.11 Different throughput requirements (ASIRS) .............................................. 72 3.12 A VSIRS resource utilization for alternative configurations ............................ 73 3.13 Performance analysis of alternate ASIRS configurations ............................... 75 3.14 Parameters for the two design configurations in Figure 3.8 ............................ 77 3.15 Comparison between the two zone cases and the no-zone
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