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| About the Editors | |
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| Contributors | |
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| Series Editor's Preface | |
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| Preface | |
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| Acknowledgements | |
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| Overview | |
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| Introduction | |
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| Durability in Vehicle Engineering | |
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| Reliability, Variation and Robustness | |
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| Load Description for Trucks | |
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| Why Is Load Analysis Important? | |
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| The Structure of the Book | |
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| Loads for Durability | |
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| Fatigue and Load Analysis | |
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| Constant Amplitude Load | |
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| Block Load | |
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| Variable Amplitude Loading and Rainflow Cycles | |
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| Rainflow Matrix, Level Crossings and Load Spectrum | |
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| Other Kinds of Fatigue | |
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| Loads in View of Fatigue Design | |
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| Fatigue Life: Cumulative Damage | |
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| Fatigue Limit: Maximum Load | |
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| Sudden Failures: Maximum Load | |
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| Safety Critical Components | |
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| Design Concepts in Aerospace Applications | |
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| Loads in View of System Response | |
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| Loads in View of Variability | |
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| Different Types of Variability | |
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| Loads in Different Environments | |
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| Summary | |
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| Methods for Load Analysis | |
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| Basics of Load Analysis | |
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| Amplitude-based Methods | |
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| From Outer Loads to Local Loads | |
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| Pre-processing of Load Signals | |
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| Rainflow Cycle Counting | |
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| Range-pair Counting | |
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| Markov Counting | |
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| Range Counting | |
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| Level Crossing Counting | |
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| Interval Crossing Counting | |
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| Irregularity Factor | |
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| Peak Value Counting | |
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| Examples Comparing Counting Methods | |
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| Pseudo Damage and Equivalent Loads | |
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| Methods for Rotating Components | |
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| Recommendations and Work-flow | |
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| Frequency-based Methods | |
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| The PSD Function and the Periodogram | |
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| Estimating the Spectrum Based on the Periodogram | |
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| Spectrogram or Waterfall Diagram | |
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| Frequency-based System Analysis | |
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| Extreme Response and Fatigue Damage Spectrum | |
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| Wavelet Analysis | |
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| Relation Between Amplitude and Frequency-based Methods | |
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| More Examples and Summary | |
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| Multi-input Loads | |
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| From Outer Loads to Local Loads | |
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| The RP Method | |
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| Plotting Pseudo Damage and Examples | |
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| Equivalent Multi-input Loads | |
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| Phase Plots and Correlation Matrices for Multi-input Loads | |
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| Multi-input Tune at Level Counting | |
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| Biaxiality Plots | |
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| The Wang-Brown Multi-axial Cycle Counting Method | |
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| Summary | |
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| Load Editing and Generation of Time Signals | |
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| Introduction | |
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| Essential Load Properties | |
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| Criteria for Equivalence | |
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| Data Inspections and Corrections | |
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| Examples and Inspection of Data | |
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| Detection and Correction | |
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| Load Editing in the Time Domain | |
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| Amplitude-based Editing of Time Signals | |
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| Frequency-based Editing of Time Signals | |
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| Amplitude-based Editing with Frequency Constraints | |
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| Editing of Time Signals: Summary | |
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| Load Editing in the Rainflow Domain | |
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| Re-scaling | |
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| Superposition | |
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| Extrapolation on Length or Test Duration | |
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| Extrapolation to Extreme Usage | |
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| Load Editing for ID Counting Results | |
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| Summary, Hints and Recommendations | |
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| Generation of Time Signals | |
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| Amplitude-or Cycle-based Generation of Time Signals | |
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| Frequency-based Generation of Time Signals | |
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| Summary | |
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| Response of Mechanical Systems | |
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| General Description of Mechanical Systems | |
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| Multibody Models | |
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| Finite Element Models | |
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| Multibody Simulation (MBS) for Durability Applications or: from System Loads to Component Loads | |
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| An Illustrative Example | |
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| Some General Modelling Aspects | |
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| Flexible Bodies in Multibody Simulation | |
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| Simulating the Suspension Model | |
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| Finite Element Models (FEM) for Durability Applications or: from Component Loads to Local Stress-strain Histories | |
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| Linear Static Load Cases and Quasi-static Superposition | |
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| Linear Dynamic Problems and Modal Superposition | |
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| From the Displacement Solution to Local Stresses and Strains | |
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| Summary of Local Stress-strain History Calculation | |
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| Invariant System Loads | |
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| Digital Road and Tyre Models | |
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| Back Calculation of Invariant Substitute Loads | |
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| An Example | |
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| Summary | |
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| Models for Random Loads | |
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| Introduction | |
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| Basics on Random Processes | |
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| Some Average Properties of Random Processes* | |
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| Statistical Approach to Estimate Load Severity | |
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| The Extrapolation Method | |
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| Fitting Range-pairs Distribution | |
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| Semi-parametric Approach | |
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| The Monte Carlo Method | |
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| Expected Damage for Gaussian Loads | |
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| Stationary Gaussian Loads | |
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| Non-stationary Gaussian Loads with Constant Mean* | |
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| Non-Gaussian Loads: the Role of Upcrossing Intensity | |
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| Bendat's Narrow Band Approximation | |
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| Generalization of Bendat's Approach* | |
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| Laplace Processes | |
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| The Coefficient of Variation for Damage | |
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| Splitting the Measured Signal into Parts | |
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| Short Signals | |
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| Gaussian Loads | |
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| Compound Poisson Processes: Roads with Pot Holes | |
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| Markov Loads | |
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| Markov Chains* | |
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| Discrete Markov Loads - Definition | |
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| Markov Chains of Turning Points | |
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| Switching Markov Chain Loads | |
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| Approximation of Expected Damage for Gaussian Loads | |
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| Intensity of Interval Upcrossings for Markov Loads* | |
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| Summary | |
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| Load Variation and Reliability | |
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| Modelling of Variability in Loads | |
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| The Sources of Load Variability: Statistical Populations | |
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| Controlled or Uncontrolled Variation | |
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| Model Errors | |
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| Reliability Assessment | |
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| The Statistical Model Complexity | |
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| The Physical Model Complexity | |
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| The Full Probabilistic Model | |
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| Monte Carlo Simulations | |
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| Accuracy of the Full Probabilistic Approach | |
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| The First-Moment Method | |
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| The Second-Moment Method | |
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| The Gauss Approximation Formula | |
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| The Fatigue Load-Strength Model | |
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| The Fatigue Load and Strength Variables | |
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| Reliability Indices | |
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| The Equivalent Load and Strength Variables | |
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| Determining Uncertainty Measures | |
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| The Uncertainty due to the Estimated Damage Exponent | |
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| The Uncertainty Measure of Strength | |
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| The Uncertainty Measure of Load | |
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| Use of the Reliability Index | |
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| Including an Extra Safety Factor | |
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| Reducing Uncertainties | |
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| Summary | |
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| Load Analysis in View of the Vehicle Design Process | |
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| Evaluation of Customer Loads | |
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| Introduction | |
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| Survey Sampling | |
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| Why Use Random Samples? | |
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| Simple Random Sample | |
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| Stratified Random Sample | |
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| Cluster Sample | |
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| Sampling with Unequal Probabilities | |
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| An Application | |
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| Simple Random Sampling in More Detail | |
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| Conclusion | |
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| Load Measurement Uncertainty | |
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| Precision in Load Severity | |
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| Pair-wise Analysis of Load Severity | |
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| Joint Analysis of Load Severity | |
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| Random Sampling of Customers | |
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| Customer Survey | |
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| Characterization of a Market | |
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| Simplified Model for a New Market | |
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| Comparison of Markets | |
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| Customer Usage and Load Environment | |
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| Model for Customer Usage | |
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| Load Environment Uncertainty | |
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| Vehicle-Independent Load Descriptions | |
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| Discussion and Summary | |
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| Derivation of Design Loads | |
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| Introduction | |
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| Scalar Load Representations | |
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| Other Load Representations | |
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| Statistical Aspects | |
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| Structure of the Chapter | |
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| From Customer Usage Profiles to Design Targets | |
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| Customer Load Distribution and Design Load | |
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| Strength Distribution and Strength Requirement | |
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| Defining the Reliability Target | |
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| Partial Safety Factor for Load-Strength Modelling | |
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| Safety Factors for Design Loads | |
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| Summary and Remarks | |
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| Synthetic Load Models | |
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| Random Load Descriptions | |
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| Models for External Load Environment | |
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| Load Descriptions in Design | |
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| Load Description for Testing | |
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| Applying Reconstruction Methods | |
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| Rainflow Reconstruction | |
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| ID and Markov Reconstruction | |
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| Spectral Reconstruction | |
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| Multi-input Loads | |
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| Standardized Load Spectra | |
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| Proving Ground Loads | |
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| Optimized Combination of Test Track Events | |
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| Optimizing with Respect to Damage per Channel | |
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| An Instructive Example | |
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| Extensions* | |
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| Hints and Practical Aspects | |
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| Discussion and Summary | |
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| Verification of Systems and Components | |
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| Introduction | |
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| Principles of Verification | |
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| Test for Continuous Improvements vs. Tests for Release | |
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| Specific Problems in Verification of Durability | |
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| Characterizing or Verification Tests | |
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| Verification on Different Levels | |
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| Physical vs. Numerical Evaluation | |
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| Summary | |
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| Generating Loads for Testing | |
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| Reliability Targets and Verification Loads | |
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| Generation of Time Signals based on Load Specifications | |
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| Acceleration of Tests | |
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| Planning and Evaluation of Tests | |
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| Choice of Strength Distribution and Variance | |
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| Parameter Estimation and Censored Data | |
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| Verification of Safety Factors | |
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| Statistical Tests for Quantiles | |
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| Discussion and Summary | |
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| Fatigue Models and Life Prediction | |
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| Short, Long or Infinite Life | |
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| Low Cycle Fatigue | |
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| High Cycle Fatigue | |
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| Fatigue Limit | |
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| Cumulative Fatigue | |
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| Arguments for the Palmgren-Miner Rule | |
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| When is the Palmgren-Miner Rule Useful? | |
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| Statistics and Probability | |
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| Further Reading | |
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| Some Common Distributions | |
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| Normal Distribution | |
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| Log-Normal Distribution | |
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| Weibull Distribution | |
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| Rayleigh Distribution | |
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| Exponential Distribution | |
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| Generalized Pareto Distribution | |
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| Extreme Value Distributions | |
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| Peak over Threshold Analysis | |
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| Fourier Analysis | |
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| Fourier Transformation | |
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| Fourier Series | |
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| Sampling and the Nyquist-Shannon Theorem | |
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| DFT/FFT (Discrete Fourier Transformation) | |
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| Finite Element Analysis | |
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| Kinematics of Flexible Bodies | |
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| Equations of Equilibrium | |
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| Linear Elastic Material Behaviour | |
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| Some Basics on Discretization Methods | |
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| Dynamic Equations | |
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| Multibody System Simulation | |
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| Linear Models | |
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| Mathematical Description of Multibody Systems | |
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| The Equations of Motion | |
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| Computational Issues | |
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| Software for Load Analysis | |
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| Some Dedicated Software Packages | |
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| Some Software Packages for Fatigue Analysis | |
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| WAFO - a Toolbox for Matlab | |
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| Bibliography | |
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| Index | |