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Dedication |
6 |
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Preface |
8 |
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Contents |
12 |
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Chapter 1: Train Scheduling |
13 |
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1.1 Introduction and Background |
13 |
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1.2 Role of Trains in the Railroad Operations Research Landscape |
14 |
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1.3 Types of Trains and Related Definitions |
17 |
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1.4 Specifying Road Trains |
19 |
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1.5 OR Challenges: Designing the Road Train Plan |
22 |
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1.5.1 Road Train Design Problem |
23 |
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1.5.2 Single Versus Multi-Block Trains |
23 |
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1.6 Train Routing/Block-to-Train Assignment Problems |
25 |
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1.6.1 Example Problem |
29 |
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1.6.2 Feasible Solution |
31 |
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1.7 Train Scheduling (Timing) Problem |
34 |
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1.7.1 Key Assumptions |
35 |
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1.7.2 Scheduling Variables |
36 |
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1.7.3 Scheduling Constraints |
36 |
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1.7.4 Cost Parameters |
37 |
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1.7.5 Observations on Solution Strategies |
38 |
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1.7.6 Special Cases |
39 |
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1.7.7 Problem Examples |
41 |
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1.8 Specifying Unit Trains |
45 |
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1.9 Local Service Specification Strategies |
46 |
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1.10 Train Plan Design Versus Real-Time Operations |
49 |
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1.11 Opportunities |
52 |
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References |
53 |
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Chapter 2: Locomotive Scheduling Problem |
55 |
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2.1 Introduction |
55 |
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2.2 Background on Locomotive Scheduling |
56 |
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2.2.1 Hard Constraints |
57 |
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2.2.2 Soft Constraints |
58 |
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2.2.3 Objective Function |
58 |
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2.3 Mathematical Models for Locomotive Scheduling |
58 |
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2.3.1 Space–Time Network Construction |
58 |
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2.3.2 Problem Size and Stage-Wise Solution Approach |
59 |
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2.3.3 Consist Flow Formulation for the LPP |
61 |
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2.3.3.1 Notation |
62 |
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2.3.3.2 Decision Variables |
62 |
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2.3.3.3 Objective Function |
63 |
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2.3.3.4 Constraints |
63 |
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2.4 Incorporating Practical Requirements |
64 |
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2.4.1 Cab-Signal Requirements |
64 |
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2.4.2 Foreign Power Requirements |
65 |
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2.5 Applications of the Model |
66 |
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2.5.1 Quantifying the Impact of Varying Minimum Connection Time |
66 |
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2.5.2 Quantifying the Effect of Changing Transport Volume on Key Performance Characteristics |
67 |
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References |
68 |
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Chapter 3: Simulation of Line of Road Operations |
69 |
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3.1 Introduction |
69 |
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3.2 Fundamental Elements for a Dispatching Algorithm |
76 |
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3.3 Developing a Dispatching Algorithm |
78 |
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3.3.1 Overview |
78 |
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3.3.2 Example |
79 |
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3.3.3 Simplified Assumptions |
89 |
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3.4 Future Directions |
90 |
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Chapter 4: Car Scheduling/Trip Planning |
91 |
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4.1 Introduction and Background |
91 |
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4.2 Car Scheduling/Trip Planning Systems in Context |
93 |
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4.3 Plan Compliance and the Value of Trip Plans |
95 |
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4.4 Current Industry Practices: Basic Car Scheduling/ Trip Planning Concepts |
96 |
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4.4.1 Current Industry Practices: Block Selection Logic |
101 |
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4.4.2 Current Industry Practices: Train Selection Logic |
101 |
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4.4.3 Current Industry Practices: Other Special Considerations |
104 |
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4.5 OR Challenge: Typical Reasons of Trip Plan Failures |
106 |
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4.6 Trip Plan Output Usages |
107 |
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4.7 OR Challenges: Alternate Approaches to Car Scheduling and Special Cases |
108 |
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4.8 Capacitation and Reservations |
113 |
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4.8.1 Specifying Capacities |
114 |
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4.8.2 Managing Reservations |
118 |
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4.9 Planning and Optimization |
119 |
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4.10 Time-Space Network Solutions |
121 |
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4.10.1 Dynamic Car Scheduling |
123 |
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4.11 Opportunities |
127 |
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References |
129 |
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Chapter 5: Railway Blocking Process |
131 |
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5.1 Introduction and Background |
131 |
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5.1.1 Impact of Blocking on System Efficiency and Service |
132 |
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5.1.2 Specifying the Blocking Plan |
134 |
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5.1.3 Plan Complexity |
135 |
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5.2 Current Industry Practices: The Blocking Rules Concept |
136 |
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5.2.1 Yard-Blocks, Train-Blocks, Class Codes, and Block Swaps |
139 |
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5.2.2 Local Service |
141 |
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5.3 The Table-Based Blocking Systems OR Challenge |
142 |
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5.4 Algorithmic Blocking |
144 |
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5.5 Examples of Areas Presenting OR Challenges |
146 |
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5.6 Semi-manual Blocking Plan Design Techniques |
148 |
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5.6.1 Incremental Blocking Plan Design Techniques |
148 |
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5.6.2 Tuning an Existing Plan |
148 |
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5.6.3 Checking Circuity and Excessive Handlings |
150 |
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5.6.4 Change Traffic Volume at a Yard |
150 |
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5.6.5 Designing Blocking Plans Using a Clean-Sheet Approach |
151 |
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5.6.6 Tuning Table-Based, Traffic Destination Attribute Rules Using Relaxation |
152 |
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5.6.7 Additional Methods for Testing Plans |
155 |
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5.6.8 Triplet Analysis for Blocking Plan Comparisons |
155 |
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5.6.9 Tree View Analysis |
157 |
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5.7 Specialized Blocking Situations |
157 |
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5.8 Blocking Plan Optimization |
161 |
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5.8.1 Considerations That Automated Blocking Optimization Techniques Should Consider |
162 |
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5.8.2 Mathematical Representation of the Block Design Optimization Problem |
163 |
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5.8.2.1 Data |
164 |
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5.8.2.2 Variables |
164 |
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5.8.2.3 Constraints |
165 |
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5.8.2.4 Objective |
166 |
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Optimization Techniques |
166 |
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Heuristic Approach |
167 |
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Initial Blocking Plan |
167 |
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Iteratively Improve the Plan |
168 |
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Resequencing Quickly |
168 |
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Finding Global Optimum |
169 |
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Changing Yard Penalties |
169 |
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Advanced Mathematical Programming |
169 |
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5.9 Additional Considerations |
171 |
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5.10 Opportunities |
172 |
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References |
173 |
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Chapter 6: Crew Scheduling Problem |
175 |
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6.1 Introduction |
175 |
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6.2 Background on Crew Scheduling |
176 |
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6.2.1 Terminology |
176 |
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6.2.2 Regulatory and Contractual Requirements |
178 |
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6.3 Mathematical Models for Crew Scheduling |
179 |
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6.3.1 Model Inputs |
179 |
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6.3.2 Space–Time Network Construction |
179 |
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6.3.3 Mathematical Formulation |
181 |
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6.3.4 Solution Methods |
183 |
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6.3.4.1 Successive Constraint Generation (SCG) |
183 |
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6.3.4.2 Quadratic Cost-Perturbation (QCP) Algorithm |
183 |
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6.4 Applications of the Model |
185 |
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6.4.1 Tactical Benefits |
185 |
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6.4.2 Planning Benefits |
186 |
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6.4.3 Strategic Benefits |
186 |
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References |
187 |
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Chapter 7: Empty Railcar Distribution |
188 |
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7.1 Introduction |
188 |
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7.2 Background on Empty Railcar Distribution |
189 |
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7.2.1 Local Distribution and Shipper Pools |
189 |
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7.2.2 Rules-Based Transaction Processing Systems |
189 |
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7.2.3 Nonintegrated Optimization Systems |
190 |
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7.3 Current Day Integrated Real-Time Optimization Systems |
190 |
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7.3.1 Model Inputs |
190 |
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7.3.1.1 Car Supply: Actual and Predicted |
191 |
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7.3.1.2 Car Orders: Actual and Predicted |
191 |
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7.3.1.3 Shipper Preferences |
191 |
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7.3.1.4 Cost Parameters |
191 |
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7.3.1.5 Operational Information |
192 |
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7.3.2 Model Framework |
192 |
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7.3.2.1 Model Preprocessing |
192 |
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7.3.2.2 Model Formulation |
192 |
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7.3.3 Model Output Post Processing |
194 |
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7.3.4 Systems Integration |
194 |
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7.3.4.1 Optimization Engine: Customer Car Order System |
195 |
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7.3.4.2 Optimization Engine-Transactional Equipment Distribution System |
195 |
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7.3.4.3 Transactional Equipment Distribution System: Car Movement Management and Tracking System |
195 |
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7.3.4.4 Optimization Model: Operational Systems: Decision Making Process Integration |
196 |
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7.3.5 Reported Benefits |
197 |
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7.3.6 Other Implementation Considerations |
197 |
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7.3.6.1 User Acceptance |
197 |
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7.3.6.2 Model Thrashing |
197 |
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7.3.7 Other Modeling Considerations |
198 |
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7.3.7.1 Endogenizing Stochasticity |
198 |
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7.3.7.2 Including Blocking Costs in Empty Car Assignment |
198 |
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7.3.8 Other Areas of Application in Rail |
198 |
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References |
199 |
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Chapter 8: Network Analysis and Simulation |
201 |
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8.1 Introduction and Background |
201 |
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8.1.1 Planning and Simulation |
202 |
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8.1.2 Other Types of Simulations |
203 |
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8.2 Types of Network Level Simulations |
203 |
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8.2.1 Uncapacitated Deterministic Simulations with Fixed Plans |
204 |
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8.2.2 Uncapacitated Deterministic Simulations with Probabilistic Connections |
205 |
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8.2.3 Capacitated Simulations with Fixed Plans |
205 |
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8.2.4 Capacitated Simulations with Dynamic Plan Elements |
207 |
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8.2.5 Full Monte-Carlo Capacitated Simulations |
208 |
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8.3 Resource Estimation |
208 |
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8.3.1 Estimation of Crews |
209 |
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8.3.2 Estimation of Locomotives |
210 |
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8.3.3 Estimation of Railcar Requirements |
211 |
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8.3.4 Estimation of Yard Workloads |
213 |
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8.4 Roles of Network Simulation |
214 |
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8.4.1 Mergers |
214 |
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8.4.2 Network Modifications |
215 |
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8.4.3 Emergency Situations or Special Circumstances |
216 |
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8.5 Average Day Analysis |
216 |
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8.5.1 Uncapacitated Average Day Analysis |
217 |
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8.5.2 Capacitated Average Day Analysis |
218 |
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8.5.2.1 Achieving a Robust Train Volume Formulation |
222 |
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8.5.2.2 Train-Block Prioritization |
223 |
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8.5.2.3 Fill Blocks |
224 |
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8.5.2.4 Capacitation by Length and Gross Weight |
224 |
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8.6 Future Directions and Opportunities |
225 |
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References |
226 |
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Chapter 9: Simulation of Yard and Terminal Operations |
228 |
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9.1 Introduction |
228 |
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9.2 Reasons to Simulate |
229 |
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9.3 The Problem |
231 |
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9.3.1 Train Arrival |
231 |
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9.3.2 Handling the Inbound Crew and Power |
232 |
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9.3.3 Inbound Car Inspection |
232 |
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9.3.4 Switch (Classify) Cars |
232 |
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9.3.5 Train Assembly |
234 |
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9.3.6 Final Train Assembly |
234 |
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9.3.7 Train Departure |
235 |
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9.4 Matching the Analytic Approach with Study Requirements |
235 |
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9.5 Building a Yard Simulation |
237 |
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9.5.1 Conceptual Design |
237 |
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9.5.1.1 Simulation Engine |
238 |
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9.5.1.2 Decision Engine |
239 |
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9.5.1.3 Inbound Process |
240 |
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9.5.1.4 Switching Process |
240 |
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9.5.1.5 Train Assembly Process |
241 |
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9.5.1.6 Departure Process |
241 |
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9.5.2 Data for Simulation |
245 |
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9.5.3 Other Issues to Be Resolved |
246 |
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9.6 Recent Past to Current State of the Art |
247 |
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9.7 Future Directions |
249 |
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Chapter 10: Operations Research in Rail Pricing and Revenue Management |
252 |
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10.1 Introduction |
252 |
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10.1.1 U.S. Freight Rail Pricing History |
252 |
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10.1.2 Revenue Management for Rail: Importance |
253 |
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10.1.3 Revenue Management for Rail: Challenges |
253 |
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10.1.4 Revenue Management for Rail: Recent Opportunities |
254 |
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10.2 Analytical Techniques in Freight Revenue Management |
255 |
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10.3 Characterizing Customer Behavior: Estimating Product Demand |
255 |
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10.3.1 Forecasting Demand Levels |
256 |
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10.3.2 Predicting Customer Price Sensitivity |
257 |
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10.4 Research in Revenue Management Models |
258 |
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10.4.1 Train and Block-Based Capacity Approaches |
258 |
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10.4.2 Service-Based Pricing Strategies |
260 |
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10.4.3 Container-Centric Yield Management |
261 |
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10.5 Future Directions and Opportunities for Revenue Management and Freight Rail |
262 |
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References |
262 |
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Chapter 11: Intermodal Rail |
264 |
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11.1 Introduction and Background Information |
264 |
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11.1.1 Definition of Intermodal |
264 |
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11.1.2 Brief History of Intermodal |
265 |
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11.1.3 Equipment Variations |
267 |
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11.1.4 Role of Railroads and IMCs |
268 |
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11.1.5 Chassis Pools, Both Domestic and International |
268 |
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11.2 Examples of Decisions to Be Made Where OR Models Can Be Used |
269 |
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11.2.1 Pricing |
269 |
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11.2.2 Container Fleet Sizing |
270 |
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11.2.3 Demand Forecasting |
270 |
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11.2.4 Assignment of Equipment to Customers |
271 |
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11.2.5 Chassis Fleet Sizing and Positioning |
271 |
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11.3 Detailed Examples of Actual Model Implementations |
272 |
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11.3.1 Empty Container Repositioning |
272 |
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11.3.1.1 Background on Problem |
272 |
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11.3.1.2 Typical Decision Making Approach |
272 |
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11.3.1.3 Optimization Approach |
273 |
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11.3.1.4 Network Construction |
274 |
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11.3.1.5 Objective Function Components |
275 |
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11.3.1.6 Constraints |
275 |
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11.3.1.7 Solution Approach |
276 |
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11.3.1.8 Results |
276 |
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11.3.2 Chassis Pool Sizing |
277 |
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11.3.2.1 Overview |
277 |
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11.3.2.2 Approach |
277 |
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11.3.3 Container Selection Process |
278 |
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11.3.3.1 Background |
278 |
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11.3.3.2 Approach |
279 |
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11.3.3.3 Supply and Demand Forecasting |
279 |
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11.3.3.4 Capacity Valuation |
280 |
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11.3.3.5 Fleet Inventory Targeting |
280 |
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11.3.3.6 Load Accept Optimization (LAO) |
281 |
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11.3.3.7 Load Routing Optimization |
281 |
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11.3.3.8 Results |
282 |
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11.4 Opportunities |
282 |
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11.4.1 Forecasting |
282 |
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11.4.2 Tactical Equipment Matching |
283 |
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Index |
284 |
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