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| Contributors | |
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| Preface | |
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| Acknowledgments | |
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| Introduction | |
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| Background | |
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| Historical Aspects of Water Distribution | |
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| Ancient Urban Water Supplies | |
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| Status of Water Distribution Systems in the 19th Century | |
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| Perspectives on Water Distribution Mains in the United States | |
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| Early Pipe Flow Computational Methods | |
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| Modern Water Distribution Systems | |
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| The Overall Systems | |
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| System Components | |
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| System Operation | |
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| The Future | |
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| References | |
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| Hydraulics of Pressurized Flow | |
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| Introduction | |
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| Importance of Pipeline Systems | |
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| Numerical Models: Basis For Pipeline Analysis | |
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| Modeling Approach | |
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| Properties of Matter (What?) | |
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| Laws of Conservation (How?) | |
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| Conservation of Mass | |
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| Newton's Second Law | |
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| System Capacity: Problems in Time and Space | |
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| Steady Flow | |
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| Turbulent Flow | |
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| Headloss Caused by Friction | |
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| Comparison of Loss Relations | |
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| Local Losses | |
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| Tractive Force | |
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| Conveyance System Calculations: Steady Uniform Flow | |
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| Pumps: Adding Energy to the Flow | |
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| Sample Application Including Pumps | |
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| Neworks--Linking Demand and Supply | |
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| Quasi-Steady Flow: System Operation | |
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| Unsteady Flow: Introduction of Fluid Transients | |
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| Importance of Waterhammer | |
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| Cause of Transients | |
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| Physical Nature of Transient Flow | |
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| Equation of State-Wavespeed Relations | |
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| Increment of Head-Change Relation | |
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| Transient Conditions in Valves | |
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| Conclusion | |
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| References | |
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| System Design: an Overview | |
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| Introduction | |
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| Overview | |
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| Definitions | |
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| Distribution System Planning | |
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| Water Demands | |
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| Planning and Design Criteria | |
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| Peaking Coefficients | |
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| Computer Models and System Modeling | |
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| Pipeline Preliminary Design | |
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| Alignment | |
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| Subsurface Conflicts | |
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| Rights-of-Way | |
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| Piping Materials | |
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| Ductile Iron Pipe (DIP) | |
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| Polyvinyl Chloride (PVC) Pipe | |
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| Steel Pipe | |
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| Reinforced Concrete Pressure Pipe (RCPP) | |
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| High-Density Polyethylene (HDPE) Pipe | |
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| Asbestos-Cement Pipe (ACP) | |
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| Pipe Material Selection | |
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| Pipeline Design | |
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| Internal Pressures | |
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| Loads on Buried Pipe | |
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| Thrust Restraint | |
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| Distribution and Transmission System Valves | |
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| Isolation Valves | |
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| Control Valves | |
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| Blow-offs | |
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| Air Release and Vacuum-Relief Valves | |
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| References | |
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| Hydraulics of Water Distribution Systems | |
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| Introduction | |
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| Configuration and Components of Water Distribution Systems | |
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| Conservation Equations for Pipe Systems | |
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| Network Components | |
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| Steady-State Hydraulic Analysis | |
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| Series and Parallel Pipe Systems | |
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| Branching Pipe Systems | |
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| Pipe Networks | |
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| Unsteady Flow in Pipe Network Analysis | |
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| Governing Equations | |
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| Solution Methods | |
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| Computer Modeling of Water Distribution Systems | |
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| Applications of Models | |
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| Model Calibration | |
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| References | |
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| Pump System Hydraulic Design | |
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| Pump Types and Definitions | |
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| Pump Standards | |
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| Pump Definitions and Terminology | |
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| Types of Centrifugal Pumps | |
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| Pump Hydraulics | |
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| Pump Performance Curves | |
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| Pipeline Hydraulics and System Curves | |
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| Hydraulics of Valves | |
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| Determination of Pump Operating Points-Single Pump | |
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| Pumps Operating in Parallel | |
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| Variable-Speed Pumps | |
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| Concept of Specific Speed | |
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| Introduction: Discharge-Specific Speed | |
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| Suction-Specific Speed | |
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| Net Positive Suction Head | |
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| Net Positive Suction Head Available | |
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| Net Positive Suction Head Required by a Pump | |
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| NPSH Margin or Safety Factor Considerations | |
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| Cavitation | |
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| Corrected Pump Curves | |
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| Hydraulic Considerations in Pump Selection | |
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| Flow Range of Centrifugal Pumps | |
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| Causes and Effects of Centrifugal Pumps Operating Outside Allowable Flow Ranges | |
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| Summary of Pump Selection | |
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| Application of Pump Hydraulic Analysis to Design of Pumping Station Components | |
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| Pump Hydraulic Selections and Specifications | |
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| Piping | |
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| Implications of Hydraulic Transients in Pumping Station Design | |
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| Effect of Surge on Valve Selection | |
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| Effect of Surge on Pipe Material Selection | |
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| References | |
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| Appendix | |
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| Hydraulic Transient Design for Pipeline Systems | |
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| Introduction to Waterhammer and Surging | |
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| Fundamentals of Waterhammer and Surge | |
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| Definitions | |
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| Acoustic Velocity | |
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| Joukowsky (Waterhammer) Equation | |
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| Hydraulic Characteristics of Valves | |
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| Descriptions of Various Types of Valves | |
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| Definition of Geometric Characteristics of Valves | |
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| Definition of Hydraulic Performance of Valves | |
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| Typical Geometric and Hydraulic Valve Characteristics | |
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| Valve Operation | |
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| Hydraulic Characteristics of Pumps | |
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| Definition of Pump Characteristics | |
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| Homologous (Affinity) Laws | |
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| Abnormal Pump (Four-Quadrant) Characteristics | |
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| Representation of Pump Data for Numerical Analysis | |
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| Critical Data Required for Hydraulic Analysis of Systems with Pumps | |
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| Surge Protection and Surge Control Devices | |
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| Critical Parameters for Transients | |
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| Critique of Surge Protection | |
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| Surge Protection Control and Devices | |
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| Design Considerations | |
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| Negative Pressures and Water Column Separation in Networks | |
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| Time Constants for Hydraulic Systems | |
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| Case Studies | |
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| Case Study with One-way and Simple Surge Tanks | |
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| Case Study with Air chamber | |
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| Case Study with Air-vaccum Breaker | |
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| References | |
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| Optimal Design of Water Distribution Systems | |
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| Overview | |
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| Problem Definition | |
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| Mathematical Formulation | |
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| Optimization Methods | |
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| Branched Systems | |
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| Looped Pipe Systems via Linearization | |
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| General System Design via Nonlinear Programming | |
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| Stochastic Search Techniques | |
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| Applications | |
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| Summary | |
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| References | |
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| Water-Quality Aspects of Construction and Operations | |
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| Introduction | |
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| Disinfection of New Water Mains | |
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| Need for Disinfection | |
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| Disinfection Chemicals | |
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| Disinfection Procedures | |
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| Testing New Mains | |
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| Main Repairs | |
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| Disposal of Highly Chlorinated Water | |
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| Disinfection of Storage Tanks | |
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| Disinfection Procedures for Filling Tanks | |
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| Underwater Inspection | |
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| Cross-Connection Control | |
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| Definitions | |
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| Cross-Connection Control Programs | |
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| Backflow Prevention | |
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| Application of Backflow Preventers | |
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| Flushing of Distribution Systems | |
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| Background | |
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| Flushing Procedures | |
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| Directional Flushing | |
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| Alternating of Disinfectants | |
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| References | |
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| Water Quality | |
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| Introduction | |
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| Overview | |
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| Definitions | |
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| Water-Quality Processes | |
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| Loss of Disinfectant Residual | |
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| Growth of Disinfection By-products | |
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| Internal Corrosion | |
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| Biofilms | |
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| Water-Quality Monitoring | |
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| Routine Monitoring | |
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| Synoptic Monitoring | |
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| Water-Quality Modeling | |
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| History | |
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| Governing Equations | |
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| Solution Methods | |
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| Data Requirements | |
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| Model Calibration | |
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| References | |
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| Hydraulic Design of Water Distribution Storage Tanks | |
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| Introduction | |
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| Basic Concepts | |
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| Equalization | |
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| Pressure Maintenance | |
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| Fire Storage | |
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| Emergency Storage | |
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| Energy Consumption | |
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| Water Quality | |
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| Hydraulic Transient Control | |
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| Aesthetics | |
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| Design Issues | |
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| Floating Versus Pumped Storage | |
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| Ground Versus Elevated Tank | |
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| Effective Versus Total Storage | |
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| Private Versus Utility Owned Tanks | |
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| Pressurized Tanks | |
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| Location | |
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| Clearwell Storage | |
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| Tanks Downstream of the Demand Center | |
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| Multiple Tanks in the Pressure Zone | |
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| Multiple Pressure-Zone Systems | |
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| Other Siting Considerations | |
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| Tank Levels | |
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| Setting Tank Overflow Levels | |
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| Identifying Tank Service Areas | |
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| Identifying Pressure Zones | |
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| Tank Volume | |
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| Trade-offs in Tank Volume Design | |
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| Standards-Driven Sizing | |
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| Functional Design | |
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| Staging Requirements | |
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| Useful Dead Storage | |
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| Other Design Considerations | |
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| Altitude Valves | |
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| Cathodic Protection and Coatings | |
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| Overflows and Vents | |
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| References | |
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| Quality of Water in Storage | |
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| Introduction | |
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| Overview | |
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| Definitions | |
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| Water Quality Problems | |
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| Chemical Problems | |
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| Microbiological Problems | |
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| Physical Problems | |
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| Mixing and Aging in Storage Facilities | |
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| Ideal Flow Regimes | |
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| Jet Mixing | |
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| Mixing Times | |
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| Stratification | |
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| Aging | |
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| Monitoring and Sampling | |
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| Routine Monitoring | |
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| Sampling Methods and Equipment | |
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| Monitoring Frequency and Location of Samples | |
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| Special Studies | |
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| Modeling | |
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| Scale Models | |
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| Computational Fluid Dynamics | |
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| Systems Models | |
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| Design and Operational Issues | |
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| Water-Quality Design Objectives | |
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| Modes of Operation: Simultaneous Inflow-Outflow Versus Fill and Draw | |
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| Flow Regimes: Complete Mix Versus Plug Flow | |
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| Stratification in Reservoirs | |
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| Inspection and Maintenance Issues | |
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| Inspections | |
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| Maintenance | |
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| References | |
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| Computer Models/Epanet | |
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| Introduction | |
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| Need for Computer Models | |
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| Uses of Computer Models | |
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| History of Computer Models | |
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| Use of a Computer Model | |
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| Network Representation | |
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| Compilation of Data | |
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| Estimation of Demand | |
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| Operating Characteristics | |
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| Reaction-Rate Information | |
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| Model Calibration | |
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| Computer Model Internals | |
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| Input Processing | |
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| Topological Processing | |
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| Hydraulic Solution Algorithms | |
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| Linear-Equation Solver | |
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| Extended-Period Solver | |
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| Water-Quality Algorithms | |
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| Output Processing | |
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| Epanet Program | |
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| Background | |
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| Program Features | |
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| User Interface | |
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| Solver Module | |
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| Programmer's Toolkit | |
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| Conclusion | |
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| References | |
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| Water Quality Modeling-Case Studies | |
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| Introduction | |
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| Design of Distribution Systems in The United States | |
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| Water Quality in Networks | |
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| Hydraulic and Water-Quality Models | |
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| Steady-State-Water Quality Models | |
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| Dynamic Water-Quality Models | |
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| Early Applications of Water-Quality Modeling | |
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| North Penn Study | |
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| South Central Connecticut Regional Water Authority | |
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| Case Study of Cabool, Missouri | |
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| Evolution of Water Quality Modeling | |
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| Modeling Propagation of Contaminants | |
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| Case Study of the North Marin Water District | |
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| Complement to the North Marin study | |
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| Waterborne Outbreak in Gideon, Missouri | |
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| Current Trends in Water-Quality Modeling | |
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| Study in Cholet, France | |
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| Case Study in Southington, Connecticut | |
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| Mixing in Storage Tanks | |
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| Summary and Conclusions | |
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| References | |
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| Calibration of Hydraulic Network Models | |
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| Introduction | |
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| Network Characterization | |
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| Network Data Requirements | |
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| Model Parameters | |
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| Identify the Intended use of the Model | |
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| Determine Estimates of the Model Parameters | |
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| Pipe Roughness Values | |
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| Distribution of Nodal Demands | |
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| Collect Calibration Data | |
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| Fire-Flow Tests | |
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| Telemetric Data | |
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| Water-Quality Data | |
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| Evaluate the Results of the Model | |
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| Perform A Macro-Level Calibration of the Model | |
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| Perform A Sensitivity Analysis | |
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| Perform A Macro-Level Calibration of the Model | |
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| Analytical Approaches | |
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| Simulation Approaches | |
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| Optimization Approaches | |
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| Future Trends | |
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| Summary And Conclusion | |
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| References | |
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| Operation of Water Distribution Systems | |
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| Introduction | |
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| How Systems Are Operated | |
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| Typical Operating Indexes | |
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| Operating Criteria | |
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| Water Quality and Operations | |
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| Emergency Operations | |
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| Monitoring of System Performance With Scada Systems | |
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| Anatomy of a Scada System | |
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| Data Archiving | |
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| Control of Water Distribution System | |
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| Control Strategies | |
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| Centralized Versus Local Control | |
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| Linking of Scada Systems with Analysis and Control Models | |
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| Data Requirements of Analysis and Control Models | |
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| Establishment of the Link | |
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| Use of Central Databases in System Control | |
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| What the Future Holds | |
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| References | |
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| Optimization Models for Operations | |
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| |
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| Introduction | |
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| Formulations for Minimizing Energy Cost Minimization | |
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| Energy Management | |
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| Management Strategies | |
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| Management Models | |
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| Optimization Models | |
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| Summary and Conclusions | |
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| Formulations to Satisfy Water Quality | |
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| Solution Methods and Applications For Water-Quality Purposes | |
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| Mathematical Programming Approach | |
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| Simulated Annealing Approach | |
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| Development of Cost Function | |
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| Sample Application | |
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| Advantages and Disadvantages of the Two Methods | |
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| Optimal Scheduling of Booster Disinfection | |
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| Background 1: Linear Superposition | |
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| Background 2: Dynamic Network Water-Quality Models in a Planning Context | |
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| Optimal Scheduling of Booster-Station Dosages as Linear Pogramming Problem | |
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| Optimal Location and Scheduling of Booster-Station Dosage as a Mixed-Integer Linear Programming Problem | |
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| Optimal Location of Booster Stations as a Maximum Set-Covering Problem | |
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| Solution of the Optimization Models | |
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| Available Software | |
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| Summary | |
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| References | |
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| Maintenance and Rehabilitation/Replacement | |
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| Introduction | |
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| Maintenance and Rehabilitation Problems | |
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| Preview of the Chapter | |
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| Unaccounted-For Water | |
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| Indicators for Unaccounted-for Water | |
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| Understanding the Causes of Unaccounted-for Water | |
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| Components of Unaccounted-for Water | |
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| Summary | |
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| Pipe Breaks | |
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| Corrosion | |
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| External Loads | |
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| Poor Tapping | |
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| Pressure-Related Breaks | |
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| Repair Versus Replacement | |
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| Hydraulic Carrying Capacity | |
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| Diagnosis of Pressure Problems | |
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| Correction of Pressure Problems | |
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| Pipe Rehabilitation Technology | |
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| Evaluation of Pipe Rehabilitation | |
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| Maintenance Information Systems | |
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| System Mapping | |
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| System Database | |
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| Geographic Information Systems | |
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| Maintenance Management Systems | |
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| SCADA Systems | |
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| References | |
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| Reliability Analysis For Design | |
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| Failure Modes For Water Distribution Systems | |
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| Need and Justification | |
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| Definitions of Distribution System Repairs | |
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| Failure Modes | |
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| Reliability: Indexes and Approaches | |
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| Practical Aspects of Providing Reliability | |
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| Improving the Reliability of Water Distribution Systems | |
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| Analyzing the Effect of Valving on System Reliability | |
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| Component Reliability Analysis | |
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| Failure Density, Failure Rate, and Mean Time To Failure | |
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| Availability and Unavailability | |
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| Review of Models Fore Reliability of Water Distribution Systems | |
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| Reliability of a System Failure | |
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| Failure Modes | |
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| Approaches to the Assessment of Reliability | |
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| Models and Techniques for Assessing Network Reliability | |
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| Overview of Reliability Measures | |
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| Observations | |
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| Measure of Link Importance | |
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| References | |