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| Preface | |
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| List of Symbols | |
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| Introduction | |
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| Vibration Sources | |
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| Definitions | |
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| Vibration Representation | |
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| Degrees of Freedom | |
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| Vibration Modes | |
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| Vibration Nodes | |
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| Coupled Modes | |
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| Fasteners | |
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| Electronic Equipment for Airplanes and Missiles | |
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| Electronic Equipment for Ships and Submarines | |
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| Electronic Equipment for Automobiles, Trucks, and Trains | |
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| Electronics for Oil Drilling Equipment | |
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| Electronics for Computers, Communication, and Entertainment | |
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| Vibrations of Simple Electronic Systems | |
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| Single Spring-Mass System Without Damping | |
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| Sample Problem--Natural Frequency of a Cantilever Beam | |
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| Single-Degree-of-Freedom Torsional Systems | |
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| Sample Problem--Natural Frequency of a Torsion System | |
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| Springs in Series and Parallel | |
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| Sample Problem--Resonant Frequency of a Spring System | |
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| Relation of Frequency and Acceleration to Displacement | |
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| Sample Problem--Natural Frequency and Stress in a Beam | |
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| Forced Vibrations with Viscous Damping | |
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| Transmissibility as a Function of Frequency | |
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| Sample Problem--Relating the Resonant Frequency to the Dynamic Displacement | |
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| Multiple Spring--Mass Systems Without Damping | |
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| Sample Problem--Resonant Frequency of a System | |
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| Component Lead Wire and Solder Joint Vibration Fatigue Life | |
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| Introduction | |
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| Vibration Problems with Components Mounted High Above the PCB | |
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| Sample Problem--Vibration Fatigue Life in the Wires of a TO-5 Transistor | |
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| Vibration Fatigue Life in Solder Joints of a TO-5 Transistor | |
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| Recommendations to Fix the Wire Vibration Problem | |
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| Dynamic Forces Developed in Transformer Wires During Vibration | |
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| Sample Problem--Dynamic Forces and Fatigue Life in Transformer Lead Wires | |
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| Relative Displacements Between PCB and Component Produce Lead Wire Strain | |
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| Sample Problem--Effects of PCB Displacement on Hybrid Reliability | |
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| Beam Structures for Electronic Subassemblies | |
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| Natural Frequency of a Uniform Beam | |
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| Sample Problem--Natural Frequencies of Beams | |
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| Nonuniform Cross Sections | |
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| Sample Problem--Natural Frequency of a Box with Nonuniform Sections | |
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| Composite Beams | |
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| Component Lead Wires as Bents, Frames, and Arcs | |
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| Electronic Components Mounted on Circuit Boards | |
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| Bent with a Lateral Load--Hinged Ends | |
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| Strain Energy--Bent with Hinged Ends | |
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| Strain Energy--Bent with Fixed Ends | |
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| Strain Energy--Circular Arc with Hinged Ends | |
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| Strain Energy--Circular Arc with Fixed Ends | |
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| Strain Energy--Circular Arcs for Lead Wire Strain Relief | |
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| Sample Problem--Adding an Offset in a Wire to Increase the Fatigue Life | |
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| Printed Circuit Boards and Flat Plates | |
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| Various Types of Printed Circuit Boards | |
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| Changes in Circuit Board Edge Conditions | |
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| Estimating the Transmissibility of a Printed Circuit Board | |
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| Natural Frequency Using a Trigonometric Series | |
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| Natural Frequency Using a Polynomial Series | |
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| Sample Problem--Resonant Frequency of a PCB | |
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| Natural Frequency Equations Derived Using the Rayleigh Method | |
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| Dynamic Stresses in the Circuit Board | |
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| Sample Problem--Vibration Stresses in a PCB | |
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| Ribs on Printed Circuit Boards | |
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| Ribs Fastened to Circuit Boards with Screws | |
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| Printed Circuit Boards With Ribs in Two Directions | |
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| Proper Use of Ribs to Stiffen Plates and Circuit Boards | |
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| Quick Way to Estimate the Required Rib Spacing for Circuit Boards | |
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| Natural Frequencies for Different PCB Shapes with Different Supports | |
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| Sample Problem--Natural Frequency of a Triangular PCB with Three Point Supports | |
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| Octave Rule, Snubbing, and Damping to Increase the PCB Fatigue Life | |
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| Dynamic Coupling Between the PCBs and Their Support Structures | |
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| Effects of Loose Edge Guides on Plug-in Type PCBs | |
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| Description of Dynamic Computer Study for the Octave Rule | |
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| The Forward Octave Rule Always Works | |
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| The Reverse Octave Rule Must Have Lightweight PCBs | |
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| Sample Problem--Vibration Problems with Relays Mounted on PCBs | |
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| Proposed Corrective Action for Relays | |
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| Using Snubbers to Reduce PCB Displacements and Stresses | |
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| Sample Problem--Adding Snubbers to Improve PCB Reliability | |
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| Controlling the PCB Transmissibility with Damping | |
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| Properties of Material Damping | |
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| Constrained Layer Damping with Viscoelastic Materials | |
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| Why Stiffening Ribs on PCBs are Often Better than Damping | |
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| Problems with PCB Viscoelastic Dampers | |
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| Preventing Sinusoidal Vibration Failures in Electronic Equipment | |
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| Introduction | |
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| Estimating the Vibration Fatigue Life | |
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| Sample Problem--Qualification Test for an Electronic System | |
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| Electronic Component Lead Wire Strain Relief | |
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| Designing PCBs for Sinusoidal Vibration Environments | |
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| Sample Problem--Determining Desired PCB Resonant Frequency | |
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| How Location and Orientation of Component on PCB Affect Life | |
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| How Wedge Clamps Affect the PCB Resonant Frequency | |
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| Sample Problem--Resonant Frequency of PCB with Side Wedge Clamps | |
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| Effects of Loose PCB Side Edge Guides | |
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| Sample Problem--Resonant Frequency of PCB with Loose Edge Guides | |
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| Sine Sweep Through a Resonance | |
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| Sample Problem--Fatigue Cycles Accumulated During a Sine Sweep | |
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| Designing Electronics for Random Vibration | |
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| Introduction | |
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| Basic Failure Modes in Random Vibration | |
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| Characteristics of Random Vibration | |
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| Differences Between Sinusoidal and Random Vibrations | |
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| Random Vibration Input Curves | |
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| Sample Problem--Determining the Input RMS Acceleration Level | |
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| Random Vibration Units | |
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| Shaped Random Vibration Input Curves | |
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| Sample Problem--Input RMS Accelerations for Sloped PSD Curves | |
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| Relation Between Decibels and Slope | |
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| Integration Method for Obtaining the Area Under a PSD Curve | |
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| Finding Points on the PSD Curve | |
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| Sample Problem--Finding PSD Values | |
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| Using Basic Logarithms to Find Points on the PSD Curve | |
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| Probability Distribution Functions | |
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| Gaussian or Normal Distribution Curve | |
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| Correlating Random Vibration Failures Using the Three-Band Technique | |
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| Rayleigh Distribution Function | |
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| Response of a Single-Degree-of-Freedom System to Random Vibration | |
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| Sample Problem--Estimating the Random Vibration Fatigue Life | |
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| How PCBs Respond to Random Vibration | |
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| Designing PCBs for Random Vibration Environments | |
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| Sample Problem--Finding the Desired PCB Resonant Frequency | |
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| Effects of Relative Motion on Component Fatigue Life | |
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| Sample Problem--Component Fatigue Life | |
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| It's the Input PSD that Counts, Not the Input RMS Acceleration | |
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| Connector Wear and Surface Fretting Corrosion | |
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| Sample Problem--Determining Approximate Connector Fatigue Life | |
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| Multiple-Degree-of-Freedom Systems | |
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| Octave Rule for Random Vibration | |
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| Sample Problem--Response of Chassis and PCB to Random Vibration | |
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| Sample Problem--Dynamic Analysis of an Electronic Chassis | |
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| Determining the Number of Positive Zero Crossings | |
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| Sample Problem--Determining the Number of Positive Zero Crossings | |
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| Acoustic Noise Effects on Electronics | |
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| Introduction | |
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| Sample Problem--Determining the Sound Pressure Level | |
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| Microphonic Effects in Electronic Equipment | |
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| Methods for Generating Acoustic Noise Tests | |
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| One-Third Octave Bandwidth | |
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| Determining the Sound Pressure Spectral Density | |
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| Sound Pressure Response to Acoustic Noise Excitation | |
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| Sample Problem--Fatigue Life of a Sheet-Metal Panel Exposed to Acoustic Noise | |
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| Determining the Sound Acceleration Spectral Density | |
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| Sample Problem--Alternate Method of Acoustic Noise Analysis | |
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| Designing Electronics for Shock Environments | |
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| Introduction | |
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| Specifying the Shock Environment | |
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| Pulse Shock | |
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| Half-Sine Shock Pulse for Zero Rebound and Full Rebound | |
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| Sample Problem--Half-Sine Shock-Pulse Drop Test | |
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| Response of Electronic Structures to Shock Pulses | |
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| Response of a Simple System to Various Shock Pulses | |
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| How PCBs Respond to Shock Pulses | |
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| Determining the Desired PCB Resonant Frequency for Shock | |
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| Sample Problem--Response of a PCB to a Half-Sine Shock Pulse | |
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| Response of PCB to Other Shock Pulses | |
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| Sample Problem--Shock Response of a Transformer Mounting Bracket | |
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| Equivalent Shock Pulse | |
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| Sample Problem--Shipping Crate for an Electronic Box | |
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| Low Values of the Frequency Ratio R | |
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| Sample Problem--Shock Amplification for Low Frequency Ratio R | |
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| Shock Isolators | |
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| Sample Problem--Heat Developed in an Isolator | |
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| Information Required for Shock Isolators | |
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| Sample Problem--Selecting a Set of Shock Isolators | |
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| Ringing Effects in Systems with Light Damping | |
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| How Two-Degree-of-Freedom Systems Respond to Shock | |
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| The Octave Rule for Shock | |
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| Velocity Shock | |
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| Sample Problem--Designing a Cabinet for Velocity Shock | |
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| Nonlinear Velocity Shock | |
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| Sample Problem--Cushioning Material for a Sensitive Electronic Box | |
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| Shock Response Spectrum | |
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| How Chassis and PCBs Respond to Shock | |
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| Sample Problem--Shock Response Spectrum Analysis for Chassis and PCB | |
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| How Pyrotechnic Shock Can Affect Electronic Components | |
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| Sample Problem--Resonant Frequency of a Hybrid Die Bond Wire | |
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| Design and Analysis of Electronic Boxes | |
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| Introduction | |
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| Different Types of Mounts | |
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| Preliminary Dynamic Analysis | |
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| Bolted Covers | |
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| Coupled Modes | |
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| Dynamic Loads in a Chassis | |
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| Bending Stresses in the Chassis | |
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| Buckling Stress Ratio for Bending | |
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| Torsional Stresses in the Chassis | |
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| Buckling Stress Ratio for Shear | |
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| Margin of Safety for Buckling | |
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| Center-of-Gravity Mount | |
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| Simpler Method for Obtaining Dynamic Forces and Stresses on a Chassis | |
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| Effects of Manufacturing Methods on the Reliability of Electronics | |
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| Introduction | |
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| Typical Tolerances in Electronic Components and Lead Wires | |
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| Sample Problem--Effects of PCB Tolerances on Frequency and Fatigue Life | |
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| Problems Associated with Tolerances on PCB Thickness | |
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| Effects of Poor Bonding Methods on Structural Stiffness | |
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| Soldering Small Axial Leaded Components on Through-Hole PCBs | |
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| Areas Where Poor Manufacturing Methods Have Been Known to Cause Problems | |
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| Avionic Integrity Program and Automotive Integrity Program (AVIP) | |
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| The Basic Philosophy for Performing an AVIP Analysis | |
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| Different Perspectives of Reliability | |
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| Vibration Fixtures and Vibration Testing | |
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| Vibration Simulation Equipment | |
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| Mounting the Vibration Machine | |
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| Vibration Test Fixtures | |
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| Basic Fixture Design Considerations | |
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| Effective Spring Rates for Bolts | |
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| Bolt Preload Torque | |
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| Sample Problem--Determining Desired Bolt Torque | |
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| Rocking Modes and Overturning Moments | |
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| Oil-Film Slider Tables | |
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| Vibration Fixture Counterweights | |
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| A Summary for Good Fixture Design | |
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| Suspension Systems | |
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| Mechanical Fuses | |
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| Distinguishing Bending Modes from Rocking Modes | |
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| Push-Bar Couplings | |
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| Slider Plate Longitudinal Resonance | |
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| Acceleration Force Capability of Shaker | |
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| Positioning the Servo-Control Accelerometer | |
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| More Accurate Method for Estimating the Transmissibility Q in Structures | |
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| Sample Problem--Transmissibility Expected for a Plug-in PCB | |
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| Bibration Testing Case Histories | |
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| Cross-Coupling Effects in Vibration Test Fixtures | |
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| Progressive Vibration Shear Failures in Bolted Structures | |
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| Vibration Push-Bar Couplers with Bolts Loaded in Shear | |
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| Bolting PCB Centers Together to Improve Their Vibration Fatigue Life | |
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| Vibration Failures Caused by Careless Manufacturing Methods | |
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| Alleged Vibration Failure that was Really Caused by Dropping a Large Chassis | |
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| Methods for Increasing the Vibration and Shock Capability on Existing Systems | |
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| Environmental Stress Screening for Electronic Equipment (ESSEE) | |
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| Introduction | |
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| Environmental Stress Screening Philosophy | |
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| Screening Environments | |
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| Things an Acceptable Screen Are Expected to Do | |
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| Things an Acceptable Screen Are Not Expected to Do | |
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| To Screen or Not to Screen, That is the Problem | |
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| Preparations Prior to the Start of a Screening Program | |
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| Combined Thermal Cycling, Random Vibration, and Electrical Operation | |
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| Separate Thermal Cycling, Random Vibration, and Electrical Operation | |
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| Importance of the Screening Environment Sequence | |
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| How Damage Can Be Developed in a Thermal Cycling Screen | |
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| Estimating the Amount of Fatigue Life Used Up in a Random Vibration Screen | |
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| Sample Problem--Fatigue Life Used Up in Vibration and Thermal Cycling Screen | |
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| Bibliography | |
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| Index | |