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2010

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Signal Analysis For Multiple Target Materials Through Wavelet Transforms, Rajat Pashine Jan 2010

Signal Analysis For Multiple Target Materials Through Wavelet Transforms, Rajat Pashine

Masters Theses

"Signal identification based on different sensing systems like microwaves, infra-red, x-rays and terahertz waves is one of the classic problems in signal processing. Earlier methods had relied mainly on the amplitude spectrum obtained by these sensing techniques mainly due to non-availability of the phase information for the signals. Most of them are based on techniques like absorbance spectrum that requires a reference material's signal for the test material's identification. They are also sensitive to noise and highly dependent on the peak detection algorithms. Modern equipments with both amplitude and phase information provide an opportunity for time-domain signal based methods that …

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Application Of Life Cycle Assessment To Estimate Environmental Impacts Of Surface Coal Mining, Ofentse Ditsele Jan 2010

Application Of Life Cycle Assessment To Estimate Environmental Impacts Of Surface Coal Mining, Ofentse Ditsele

Masters Theses

"Coal plays an important role in meeting the energy needs of the World. Given its abundance and low cost, its use is bound to increase with the growing energy demand. Despite its importance, there are concerns over coal's environmental burdens. In order to extract and use coal in a sustainable manner, sustainability assessment has to be comprehensive. Life Cycle Assessment (LCA) provides systematic and quantifiable measures for assessing environmental burdens of products and processes. Extensive LCA work has been done on coal use, particularly in electricity generation, but, the coal mining stage has been neglected, for the most part. This …

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Finite Element Analysis And Fatigue Test On The Bicuspids To Support Theory Of Abfraction, Madhuchandra Mahadevaswamy Jan 2010

Finite Element Analysis And Fatigue Test On The Bicuspids To Support Theory Of Abfraction, Madhuchandra Mahadevaswamy

Masters Theses

"Abfraction is a small crack or notch found at the cervical areas of a teeth due to the loss of enamel tissues in the teeth. Proposed explanations for are that it is caused by toothbrush abrasion, acid erosion, and the mechanical forces applied on the teeth due to chewing, biting, tongue activity. There is disagreement among dentists as to the primary causes of abfraction. Some dentists believe that abfraction is caused by toothbrush abrasion and erosion due to acidic food and drinks. Other dentists believe that tensile and compressive forces acting on the teeth from non-axial, cyclical loading over an …

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Zinc Iron Phosphate Glasses For Enameling Applications, Sagnik Saha Jan 2010

Zinc Iron Phosphate Glasses For Enameling Applications, Sagnik Saha

Masters Theses

"New compositions of low temperature black glasses were developed that are suitable as frits for enameling soda-lime silicate (S-L-S) glass substrates. Zinc iron phosphate glasses are of interest for this application because they possess dilatometric low softening points (under 600ºC) and have coefficients of thermal expansion that are compatible with S-L-S glass (in the range 90-110x10⁻⁷/ºC). The development of compositions with excellent chemical durability, particularly in acidic conditions, is also desired. Compositional modification were made to the (Na₂O+K₂O)·ZnO·MnO·Fe₂O₃·P₂O₅ glass system using design of experiments. The compositional boundaries used in the design were based on earlier work at Missouri S&T. The …

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Dynamic Ant Colony Optimization For Globally Optimizing Consumer Preferences, Pavitra Dhruvanarayana Jan 2010

Dynamic Ant Colony Optimization For Globally Optimizing Consumer Preferences, Pavitra Dhruvanarayana

Masters Theses

"Consumer preference for any product or product feature can be expressed in the form of a utility function. Many such utility functions form a part of a preference map, where each of these are expressed in terms of the attributes defining the product or the product feature. In order to optimize the design, it is required to optimize the overall utility function obtained by a mathematical combination of individual utility functions defined in the preference map. The objective of this research is to devise and implement an algorithm to optimize all the individual utility functions comprised in a preference map …

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Enhanced Photorefractivity In A Polymeric Composite Photosensitized With Modified Carbon Nanotubes, Naveen Kumar Lingam Jan 2010

Enhanced Photorefractivity In A Polymeric Composite Photosensitized With Modified Carbon Nanotubes, Naveen Kumar Lingam

Masters Theses

"This work involves the photosensitization of photorefractive polymeric composites through the inclusion of multiwalled and singlewalled carbon nanotubes grafted to poly(N-vinyl carbazole). The photorefractive nature of the holograms gratings was established using two-beam-coupling, yielding two-beam-coupling gain coefficients approaching 80 cm⁻¹. Degenerate-four-wave-mixing experiments exhibited diffraction efficiencies as high as 60% as well as over-modulation voltages as low as ~ 40 V/µm. These notable figures of merit indicate that the grafting of the various carbon nanotubes to the poly(N-vinyl carbazole) polymer resulted in enhanced photorefractive performance. The mechanism responsible for this enhancement in photorefractive performance is investigated using a variety of experimental …

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Water Analysis For Emerging Environmental Contaminants, Xiaoliang Cheng Jan 2010

Water Analysis For Emerging Environmental Contaminants, Xiaoliang Cheng

Masters Theses

"The presence of emerging environmental contaminants in water bodies used either as drinking water or for recreational purpose has received considerable attention in the recent years. The emerging environmental contaminants can be defined as a wide range of chemicals that have been determined in the environment which may present serious health risks for humans. The occurrence of these contaminants indicate that both household and industrial chemicals have been introduced to water resources, a wide variety of chemicals, such as disinfection byproducts, pharmaceutical and personal care products and so on, have been detected at cetiain levels in either water bodies or …

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Methodology And Applications Of Electrostatic Discharge Current Reconstruction By Near-Field Scanning Technique, Wei Huang Jan 2010

Methodology And Applications Of Electrostatic Discharge Current Reconstruction By Near-Field Scanning Technique, Wei Huang

Masters Theses

"Electrostatic discharge (ESD) can cause interference in or damage to circuits or systems in many ways e.g., by E- field or H- field coupling or via conduction paths. Although one can roughly estimate the voltage and current at the injection location during an ESD event, the real offending parameter is mostly the ESD current spreading throughout the system. Those currents can be simulated if great simplifications of the system are acceptable. However, even in moderately complex systems, the ability to simulate is limited by a lack of models and computational resources. Independent of the complexity, but obviously not free of …

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Intelligent Computational Argumentation For Evaluating Performance Scores In Multi-Criteria Decision Making, Rubal Wanchoo Jan 2010

Intelligent Computational Argumentation For Evaluating Performance Scores In Multi-Criteria Decision Making, Rubal Wanchoo

Masters Theses

"Multi Criteria Decision Making (MCDM) is a discipline aimed at assisting multiple stakeholders in contemplating a decision paradigm in an uncertain environment. The decision analysis to be performed involves numerous alternative positions assessed under varied criterion. A performance score is assigned for each alternative in terms of every criterion and it represents satisfaction of the criteria by that alternative. In a collaborative decision making environment, performance scores are either obtained when a consensus can be reached among stakeholders on a particular score or in some cases or controversial when stakeholders do not agree with each other about them. In the …

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Automation Of Cad Model Based Assembly Simulations Using Motion Capture, Anup Madhav Vader Jan 2010

Automation Of Cad Model Based Assembly Simulations Using Motion Capture, Anup Madhav Vader

Masters Theses

"The manufacturing industry often uses text and video as a supplement for worker training procedures. Unfortunately, text is often difficult to follow and video lends itself to occlusion issues. CAD based animations of assembly operations can overcome these shortcomings while offering greater potential for operations analysis and simulation flexibility. However, creating such CAD based training simulations manually is a time intensive task and many a times fail to reveal the practical assembly issues faced in the real world. Thus, it is highly beneficial to be able to automate these simulations using motion capture from a physical environment. This thesis research …

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Development Of Novel Backscatter Communication Systems Using A Multi-Hop Framework And Distributed Beamforming, Vikram Reddy Surendra Jan 2010

Development Of Novel Backscatter Communication Systems Using A Multi-Hop Framework And Distributed Beamforming, Vikram Reddy Surendra

Masters Theses

"The goal of this thesis it to develop a wireless networking framework for battery-free devices based on passive, backscatter communication. In contrast to traditional, active communication systems, where the radio signal has to be generated using large amount of energy from batteries, the passive systems reflect the RF signal. The information is encoded by modulating the reflected signal, which consumes significantly less energy than active transmission. The existing passive, backscatter systems have limited communication capabilities. For example, the Radio Frequency Identification (RFID) systems support short-distance, direct communication between active reader and passive tags. The communication range is limited due to …

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Neural Mrac Based On Modified State Observer, Yang Yang Jan 2010

Neural Mrac Based On Modified State Observer, Yang Yang

Masters Theses

"A new model reference adaptive control design method with guaranteed transient performance using neural networks is proposed in this thesis. With this method, stable tracking of a desired trajectory is realized for nonlinear system with uncertainty, and modified state observer structure is designed to enable desired transient performance with large adaptive gain and at the same time avoid high frequency oscillation. The neural network adaption rule is derived using Lyapunov theory, which guarantees stability of error dynamics and boundedness of neural network weights, and a soft switching sliding mode modification is added in order to adjust tracking error. The proposed …

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Cover And Contents Jan 2010

Cover And Contents

Turkish Journal of Physics

No abstract provided.

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Minimize End-To-End Delay Through Cross-Layer Optimization In Multi-Hop Wireless Sensor Networks, Yibo Xu Jan 2010

Minimize End-To-End Delay Through Cross-Layer Optimization In Multi-Hop Wireless Sensor Networks, Yibo Xu

Masters Theses

"End-to-end delay plays a very important role in wireless sensor networks. It refers to the total time taken for a single packet to be transmitted across a network from source to destination. There are many factors could affect the end-to-end delay, among them the routing path and the interference level along the path are the two basic elements that could have significant influence on the result of the end-to-end delay. This thesis presents a transmission scheduling scheme that minimizes the end-to-end delay when the node topology is given. The transmission scheduling scheme is designed based on integer linear programming and …

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A Real-Time Visualization Of An/Pss-14 Audio Alert Signals For Land Mine Detection Validation, Nitin Kolekar Jan 2010

A Real-Time Visualization Of An/Pss-14 Audio Alert Signals For Land Mine Detection Validation, Nitin Kolekar

Masters Theses

"The central idea of the current research is visualization of audio alerts from AN/PSS-14. A visualization device connected to the arm of PSS-14 will show real-time display of MD and GPR Audio Alert signals from PSS-14. This visualization device displays both amplitude-time and spectral frequency-time formats of the signals. The latter format achieves visual separation of combined, simultaneous, MD and GPR alerts. The joint occurrence of MD and GPR signals in a specific time window confirms the presence of landmine. This window is defined by the time of occurrence of MD peak and time of occurrence GPR diffraction from onset …

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Cloud Security Requirements Analysis And Security Policy Development Using A High-Order Object-Oriented Modeling Technique, Kenneth Kofi Fletcher Jan 2010

Cloud Security Requirements Analysis And Security Policy Development Using A High-Order Object-Oriented Modeling Technique, Kenneth Kofi Fletcher

Masters Theses

"Security continues to be a major challenge for cloud computing, and it is one that must be addressed if cloud computing is to be fully accepted. Most technological means of securing non-cloud computing systems can be either applied directly or modified to secure a cloud; however, no integrated model-based methodology is yet available to analyze cloud security requirements and develop policy to deal with both internal and external security challenges. This work proposes just such a methodology and demonstrates its application with specific cases. Cloud assets are represented by high order object models, and misuse cases together with malactivity swimlane …

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Dynamic Networking For Programmable Logic Controller Communication, Richard Andrew Hardison Jan 2010

Dynamic Networking For Programmable Logic Controller Communication, Richard Andrew Hardison

Masters Theses

"This thesis confronts the issue of set path communication in Programmable Logic Controllers (PLCs). In order to increase reliability in a networked automated process, it is necessary to develop a dynamic method of communication between PLCs. Three methods for dynamic messaging in PLCs are explored in this work. These methods are based on the real-time reconfiguration of message paths when communication fails on the originally configured path. The simplest method involves replacing the original message block with an Add-On Instruction (AOI) which can accept multiple communication paths and has the ability to switch between these paths to maintain communication. A …

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Calcium Carbonate Precipitation Mechanisms And Geochemical Analysis Of Particulate Material Found Within The Waters Of Maramec Spring, St. James, Missouri, Kyle Steven Rybacki Jan 2010

Calcium Carbonate Precipitation Mechanisms And Geochemical Analysis Of Particulate Material Found Within The Waters Of Maramec Spring, St. James, Missouri, Kyle Steven Rybacki

Masters Theses

"The purpose of the present study is to determine whether a mineral phase is precipitating from solution in the natural Maramec Spring system giving the spring water a milky blue color, to identify the mineral phase, and to investigate potential mechanisms for inducing precipitation. Maramec Spring is a first-order magnitude spring located 11 km southeast of St. James, Missouri. The water that expels from Maramec Spring varies between being near saturation, but undersaturated in calcium, with respect to calcite (saturation index of 0.994 mg/L). Moving downstream, away from the conduit, the spring waters increase in pH and temperature. Eh is …

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Modeling The Practical Performance Of Switched-Capacitor Converters And A Method For Automating State-Space Model Generation, Jordan M. Henry Jan 2010

Modeling The Practical Performance Of Switched-Capacitor Converters And A Method For Automating State-Space Model Generation, Jordan M. Henry

Masters Theses

"A new modeling technique and a method for automating the modeling process are introduced for analyzing complex switched-capacitor (SC) converters. The model uses conventional circuit analysis methods to derive state-space models of each switching state. Steady-state performance is derived and expressed as an equivalent resistance. Whereas previous techniques have provided either the detailed performance of a simple SC converter or the limiting performance of a complex SC converter, this new model is flexible enough to provide detailed performance for any practical converter. Nonuniform component choices, asymmetric duty cycles, and other deviations from an ideal converter can be readily included. Dynamics …

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Power Distribution Network Inductance Calculation, Transient Current Measurement And Conductor Surface Roughness Extraction, Fan Zhou Jan 2010

Power Distribution Network Inductance Calculation, Transient Current Measurement And Conductor Surface Roughness Extraction, Fan Zhou

Masters Theses

"The first part in the thesis discussed the modeling of the mid-frequency inductance for Zpp type plane pairs in power distribution networks (PDN). It is a key step for the placement of the decoupling capacitors. This paper gives an efficient approach for the calculation of the inductance for different capacitor placements. The PEEC based formulations takes advantage of the opposite currents in the planes. This leads to compute time reductions and memory savings for both the element calculation and the matrix solve step. A formulation is used where placement of capacitors leads to only small changes in the circuit matrix. …

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Reverberation Reduction In A Room For Multiple Positions, Raghavendra Ravikumar Jan 2010

Reverberation Reduction In A Room For Multiple Positions, Raghavendra Ravikumar

Masters Theses

"Reverberation in a room occurs when the direct path sound from a sound source undergoes multiple reflections from the walls of the room before reaching the listener. An impulse response of the room can be measured called the room impulse response (RIR) which captures the effects of the room. This can be represented digitally on a computer. A filter is designed to cancel the effects of the room using the information in the room impulse response. This filter is called an equalization filter and is usually placed between the source signal and loudspeaker to perform the equalization. The RIR changes …

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Quantification Of Uncertainty In Aerodynamic Heating Of A Reentry Vehicle Due To Uncertain Wall And Freestream Conditions, Benjamin R. Bettis Jan 2010

Quantification Of Uncertainty In Aerodynamic Heating Of A Reentry Vehicle Due To Uncertain Wall And Freestream Conditions, Benjamin R. Bettis

Masters Theses

"The primary focus of this study is to demonstrate an efficient approach for uncertainty quantification of surface heat flux to the spherical non-ablating heatshield of a generic reentry vehicle due to epistemic and aleatory uncertainties that may exist in various parameters used in the numerical solution of hypersonic, viscous, laminar blunt-body flows with thermo-chemical non-equilibrium. Two main uncertainty sources were treated in the computational fluid dynamics (CFD) simulations: (1) aleatory uncertainty in the freestream velocity and (2) epistemic uncertainty in the recombination efficiency for a partially catalytic wall boundary condition. The Second-Order Probability utilizing a stochastic response surface obtained with …

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Measuring Blast Induced Rock Damage From Pre-Splitting Sandstone By Applying The Multichannel Analysis Of Surface Waves Geophysical Method, Charles Bradford Zdazinsky Jan 2010

Measuring Blast Induced Rock Damage From Pre-Splitting Sandstone By Applying The Multichannel Analysis Of Surface Waves Geophysical Method, Charles Bradford Zdazinsky

Masters Theses

"Many blasting applications in the mining industry demand that the hard rock being blasted remains structurally competent. For example, pre-splitting is a common technique to reduce fracturing, and operators of dimension stone quarries use this blasting method to eliminate overbreak. When pre-split design parameters are not applied correctly, there will be a redistribution of stresses within the rock, resulting in Blast Induced Rock Damage (BID). Advances in geophysical technology are enabling blast technicians to monitor BID and then use the results to correctly design their blasts. The Multichannel Analysis of Surface Waves (MASW) geophysical method is new technology that is …

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Slip Ramp Spacing Design For Truck Only Lanes Using Microscopic Simulation, Manoj Vallati Jan 2010

Slip Ramp Spacing Design For Truck Only Lanes Using Microscopic Simulation, Manoj Vallati

Masters Theses

"This research work proposes recommendations for slip ramp spacing between the TOLs and the general GPLs along Missouri rural interstate highways using a microscopic simulation model, VISSIM. Simulation of peak period rural traffic conditions indicated that heavy vehicle speeds were directly proportional to the lengths of the merge, diverge, and link sections. The proposed design recommendations for slip ramp spacing are based on the results of these section lengths. Design of experiments was carried out using a central composite design. As the slip ramp spacing depended heavily on the lane change behavior of drivers, a sensitivity analysis was performed of …

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A Value Model For Product Development Process Using Lean Principles, Salik Yadav Jan 2010

A Value Model For Product Development Process Using Lean Principles, Salik Yadav

Masters Theses

"This research presents a value quantification model for multi-stage product development Process (PDP) using lean value principles. The PDP stages considered in this research include conceptual development, systems design, detailed design and prototyping stages. The value at any of the PDP stages is formulated as a function of six factors: (a) importance of customer requirements, (b) cost of customer's ownership, (c) parts/service availability, (d) weighted average cost of capital, (e) information evolution, and (f) risk reduction. Factors (a)-(d) are adequately addressed in the literature. This study focuses on information evolution and risk reduction factors. These two factors are defined by …

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Event Detection From Click-Through Data Via Query Clustering, Prabhu Kumar Angajala Jan 2010

Event Detection From Click-Through Data Via Query Clustering, Prabhu Kumar Angajala

Masters Theses

"The web is an index of real-world events and lot of knowledge can be mined from the web resources and their derivatives. Event detection is one recent research topic triggered from the domain of web data mining with the increasing popularity of search engines. In the visitor-centric approach, the click-through data generated by the web search engines is the start up resource with the intuition: often such data is event-driven. In this thesis, a retrospective algorithm is proposed to detect such real-world events from the click-through data. This approach differs from the existing work as it: (i) considers the click-through …

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Population Control In Evolutionary Algorithms, Jason Edward Cook Jan 2010

Population Control In Evolutionary Algorithms, Jason Edward Cook

Masters Theses

"Traditional evolutionary algorithms (EAs) are powerful robust problem solvers that have several fixed parameters which require prior specification. Having to determine good values for any of these parameters can be problematic, as the performance of EAs is generally very sensitive to these parameters, requiring expert knowledge to set optimally without extensive use of trial and error. Parameter control is a promising approach to achieving this automation and has the added potential of increasing EA performance based on both theoretical and empirical evidence that the optimal values of EA strategy parameters change during the course of executing an evolutionary run. While …

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Multi Axis Slicing For Rapid Prototyping, Divya Kanakanala Jan 2010

Multi Axis Slicing For Rapid Prototyping, Divya Kanakanala

Masters Theses

"With multi-axis capability, direct laser deposition process can produce a metal part without the usage of support structures. In order to fully utilize such a capability, a slicing method for multi-axis metal deposition process is discussed. Using the geometry information of adjacent layers, the slicing direction and layer thickness can be changed as needed. A hierarchy structure is designed to manage the topological information which is used to determine the slicing sequence. The parallel slicing process is studied to build hollow type structure. With such a character, the hole like feature can be deposited directly to save the required machining …

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Strategic Criteria For Evaluating Inland Freight Hub Locations, Robert Tyler Lipscomb Jan 2010

Strategic Criteria For Evaluating Inland Freight Hub Locations, Robert Tyler Lipscomb

Masters Theses

"The aim of this thesis is to develop criteria that can be used to evaluate the current capabilities and sustainability of inland freight hubs. A review of the literature highlights the need for a more efficient freight distribution system to combat supply chain deficiencies and the important role that inland freight hubs play in creating this system. Also in the literature is a call for a more comprehensive approach to hub development decisions and the use of multi-criteria decision analysis. The decision to devote resources to logistics developments in a specific region must consider many factors that are both quantitative …

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Prediction Of Soft Error Response Of Integrated Circuits To Electrostatic Discharge Injection Via Simulation Field; Package Interaction For Electrostatic Discharge Soft Error Prediction; Full Wave Model For Simulating Noise Ken Electrostatic Discharge Generator, Argha Nandy Jan 2010

Prediction Of Soft Error Response Of Integrated Circuits To Electrostatic Discharge Injection Via Simulation Field; Package Interaction For Electrostatic Discharge Soft Error Prediction; Full Wave Model For Simulating Noise Ken Electrostatic Discharge Generator, Argha Nandy

Masters Theses

"In the first section, a concept for analyzing soft error response in ICs to ESD via coupling through flex cable structures is presented. Its novelty lies in accounting for the transient electromagnetic fields radiated by the ESD generator that couples to the flex cable PCB thereby causing disturbance on the IC under test. This is accomplished in three stages; first by developing a full wave model of the DUT which includes modeling the PCB and flex cable geometry and validating it in frequency domain with regard to the transfer impedance. This followed by combining the ESD generator with the DUT …

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