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Inter-Rater Reliability Of Lumbar Segmental Instability Tests And The Subclassification, Faisal Mohammad Alyazedi

Loma Linda University Electronic Theses, Dissertations & Projects

Objectives: This study investigated the inter-rater reliability of three structural end-range lumbar segmental instability tests with the highest positive Likelihood Ratio against flexion-extension radiographs, and three functional mid-range clinical tests that predict the success of lumbar stabilization exercises in patients with recurrent or chronic low back pain (R/CLBP). It also investigated the reliability of lumbar segmental instability subclassification as: Functional, Structural and Combined Instability. Method: 40 adult with R/CLBP patients (30 men and 10 women), 18 to 80 years of age, underwent repeated measurements of specific clinical tests for structural or functional lumbar segmental instability. Results: Other than the Lack …

Semi-Markov Model Of A Series-Parallel System Subject To Preventive Maintenance, M. A. El-Damcese, A. N. Salem, N. S. Temraz

Journal of Statistics Applications & Probability

The purpose of this paper is to analyze a series-parallel system by using semi-Markov process. There is a preventive maintenance action provided to the system in order to increase the life time of the system. We suppose that the failure, repair, and maintenance times are stochastically independent random variables each having an arbitrary distribution. The kernel matrix associated with this system is constructed. Expressions for mean sojourn times, steady-state availability, availability function, reliability function, mean time to failure, and mean time to repair are presented. Numerical solutions of the system are obtained.

Load Path Uncertainty In A Wood Structure And The Effect On Structural Reliability, Wenqi Wang, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

The roof truss bearing points of a light-framed wood house were instrumented with load cells. It was found that under dead load alone, symmetric and theoretically identical truss reactions have significant variation. A similar degree of reaction discrepancy was found under the application of uplift pressures caused by hurricane winds. Analysis revealed that the majority of this discrepancy is caused by inherent uncertainties in load path. Although uncertainties in load magnitude and material resistance are accounted for in design by use of appropriate load and resistance factors, load path is generally taken to be deterministic. In this study, load path …

Progressive Reliability Method And Its Application To Offshore Mooring Systems, Mir Emad Mousavi, Paolo Gardoni, Mehdi Maadooliat

Mathematics, Statistics and Computer Science Faculty Research and Publications

Assessing the reliability of complex systems (e.g. structures) is essential for a reliability-based optimal design that balances safety and costs of such systems. This paper proposes the Progressive Reliability Method (PRM) for the quantification of the reliability of complex systems. The proposed method is a closed-form solution for calculating the probability of failure. The new method is flexible to the definition of “failure” (i.e., can consider serviceability and ultimate-strength failures) and uses the rules of probability theory to estimate the failure probability of the system or its components. The method is first discussed in general and then illustrated in two …

Reliability-Based Conversion Of A Structural Design Code For Railway Prestressed Concrete Sleepers, A M. Remennikov, Martin Murray, Sakdirat Kaewunruen

Alex Remennikov

"Ballasted railway track is very suitable for heavy-rail networks because of its many superior advantages in design, construction, short- and long-term maintenance, sustainability, and life cycle cost. An important part of the railway track system, which distributes the wheel load to the formation, is the railway sleeper. Improved knowledge has raised concerns about design techniques for prestressed concrete (PC) sleepers. Most current design codes for these rely on allowable stresses and material strength reductions. However, premature cracking of PC sleepers has been found in railway tracks. The major cause of cracking is the infrequent but high-magnitude wheel loads produced by …

Technology Agnostic Analysis And Design For Improved Performance, Variability, And Reliability In Thin Film Photovoltaics, Sourabh Dongaonkar

Open Access Dissertations

Thin film photovoltaics (TFPV) offer low cost alternatives to conventional crystalline Silicon (c-Si) PV, and can enable novel applications of PV technology. Their large scale adoption however, requires significant improvements in process yield, and operational reliability. In order to address these challenges, comprehensive understanding of factors affecting panel yield, and predictive models of performance reliability are needed. This has proved to be especially challenging for TFPV for two reasons in particular. First, TFPV technologies encompass a wide variety of materials, processes, and structures, which fragments the research effort. Moreover, the monolithic manufacturing of TFPV modules differs significantly from that of …

Dc, Microwave, And Noise Properties Of Gan Based Heterojunction Field Effect Transistors And Their Reliability Issues, Congyong Zhu

Theses and Dissertations

AlGaN/GaN and InAlN/GaN-based heterojunction field effect transistors (HFETs) have demonstrated great high power and high frequency performance. Although AlGaN/GaN HFETs are commercially available, there still remain issues regarding long-term reliability, particularly degradation and ultimately device failure due to the gate-drain region where the electric field peaks. One of the proposed degradation mechanisms is the inverse-piezoelectric effect that results from the vertical electric field and increases the tensile strain. Other proposed mechanisms include hot-electron-induced trap generation, impurity diffusion, surface oxidation, and hot-electron/phonon effects. To investigate the degradation mechanism and its impact on DC, microwave, and noise performance, comprehensive stress experiments were …

Reliable Integrated Circuits Design And Test At Sub-45nm Technologies, Jifeng Chen

Doctoral Dissertations

The rapid scaling of CMOS technology into the 45nm feature node or below enables the design of higher performance chips through the construction of complex and powerful circuitry. Under area and power constraints similar to those of the past, circuit performance can raise to multi-GHz. The major impulse is that current design can provide an abundance of functionalities with a compacted layout of millions of transistors in a small chip area. However, shrinking transistor dimensions and highly condensed design layout inevitably raise reliability issues including a notable impact on performance, e-specially aging effects and process variations. The timing uncertainties introduced …

The Case Against Percentage Grades, Thomas R. Guskey

Educational, School, and Counseling Psychology Faculty Publications

It’s time to abandon grading scales that distort the accuracy, objectivity, and reliability of students’ grades.

Adaptation And The Courtroom: Judging Climate Science, Kirsten Engel, Jonathan Overpeck

Michigan Journal of Environmental & Administrative Law

Climate science is increasingly showing up in courtroom disputes over the duty to adapt to climate change. While judges play a critical role in evaluating scientific evidence, they are not apt to be familiar with the basic methods of climate science nor with the role played by peer review, publication, and training of climate scientists. This Article is an attempt to educate the bench and the bar on the basics of the discipline of climate science, which we contend is a distinct scientific discipline. We propose a series of principles to guide a judge’s evaluation of the reliability and weight …

Reliability Assessment Of Smart Grid Considering Cyber-Power Interdependencies, Bamdad Falahati

Theses and Dissertations

Smart grid initiatives are becoming more and more achievable through the use of information infrastructures that feature peer-to-peer communication, monitoring, protection and automated control. The analysis of smart grid operation requires considering the reliability of the cyber network as it is neither invulnerable nor failure free. The objective of this dissertation is to categorize interdependencies between cyber and power networks and propose mathematical evaluation models to calculate the reliability of the power network when considering failures of the cyber network. This study categorizes interdependencies between cyber and power networks into direct and indirect. In this research direct interdependencies among cyber-power …

Utilizing Atcs Data To Inform A Dynamic Reassignment System For Muni Metro Light Rail Vehicles Departing Embarcadero Station, April M. Hickey

Master's Theses

This is a report of a professional project intended to act as an informational tool for the evaluation of a dynamic dispatch system at Embarcadero Station for the San Francisco Municipal Transportation Agency (SFMTA). Systems that operate dispatch algorithms do so in response to on-time performance and reliability. The optimization problem is documented in many transportation contexts including airline networks, bus dispatch, and freight routing. According to the research, optimizing available options and re-routing based on available options can create a more efficient system that would minimize operating costs and improving service reliability for customers.

The methodology presented here uses …

Development And Testing The Validity And Reliability Of Items And Scales To Assess Physical Activity Behavior Of Adults In The Expanded Food And Nutrition Education Program, Tarana Khan

All Dissertations

Given the rising prevalence of obesity and other chronic diseases in the United States, the Expanded Food and Nutrition Education Program (EFNEP) includes physical activity as a core educational component along with diet quality, food safety, food resource management and food security. According to the Dietary Guidelines for Americans, research supports that participation in regular physical activity helps people maintain a healthy weight and prevent excess weight gain. When combined with reduced calorie intake, physical activity may aid weight loss and the maintenance of weight loss.
Two evaluation instruments are used in EFNEP nationwide. Nutritional intake is measured by a …

Reliability Analysis Of Shallow Foundations Bearing Capacity On Sand, Ali Alhajami

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Bearing capacity of shallow foundation is one of the most challenging problems for engineers. The difficulty comes from multiple sources of variability and uncertainty. There is an uncertainty in live load. Soil properties including: unit weight, cohesion, and angle of friction represent sources of variability in the determining bearing capacity. The current theories used in practice only estimate bearing capacity and does not give an exact value for it because of these sources of variability. Currently, there are Terzaghi, Meyerhof, Vesic, and Hansen theories for dealing with this problem. Based on previous research Terzaghi theory was found to be the …

Description Of System Fault Behavior Model Based On Polychromatic Sets, Guangyan Zhao, Gang Zhao, Yufeng Sun, Weiwei Hu

Applied Mathematics & Information Sciences

The system fault behavior model was investigated by the author first. System fault behavior model describes the occurrence and development process of malfunction in product, and analyzes the transmission process of unit malfunction in system and effects of various factors on system. In order to realize simulation of system fault behavior, it is necessary to perform formalized process of system fault behavior model, so as to acquire the mathematic description required by computer simulation. So the formalized description of fault behavior model (FBM) based on polychromatic sets theory was introduced. With consideration of the characteristics of model hierarchy and information …

Parameters Optimization Of Copper Wire Bonding On Thin Small Outline Package, S Srikamonsirisak, U Tantinuchawong, Y Satirakul

Journal of Metals, Materials and Minerals

With significant rising of Au price, there is growing demand to implement Cu wire bonding as an alternative method for Au wire bonding. However, there are several challenges to overcome because Cu is easily oxidized and its property is harder than Au. The oxidation deteriorates bondability and bond reliability, while the greater wire hardness leads to the more severe wire bonding parameters (higher force, higher power, higher temperature), which results in physical damage of the bond pad and underlying layers. This paper reveals wire bonding parameters optimization in order to implement Cu wire bonding in high volume production environment with …

Reliability-Based Design Optimization Of Concrete Flexural Members Reinforced With Ductile Frp Bars, Bashar Behnam, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

In recent years, ductile hybrid FRP (DHFRP) bars have been developed for use as tensile reinforcement. However, initial material costs regain high, and it is difficult to simultaneously meet strength, stiffness, ductility, and reliability demands. In this study, a reliability-based design optimization (RBDO) is conducted to determine minimum cost DHFRP bar configurations while enforcing essential constraints. Applications for bridge decks and building beams are considered, with 2, 3, and 4-material bars. It was found that optimal bar configuration has little variation for the different applications, and that overall optimized bar cost decreased as the number of bar materials increased.

Performance And Reliability Study And Exploration Of Nand Flash-Based Solid State Drives, Guanying Wu

Theses and Dissertations

The research that stems from my doctoral dissertation focuses on addressing essential challenges in developing techniques that utilize solid-state memory technologies (with emphasis on NAND flash memory) from device, circuit, architecture, and system perspectives in order to exploit their true potential for improving I/O performance in high-performance computing systems. These challenges include not only the performance quirks arising from the physical nature of NAND flash memory, e.g., the inability to modify data in-place, read/write performance asymmetry, and slow and constrained erase functionality, but also the reliability drawbacks that limits solid state drives (SSDs) from widely deployed. To address these challenges, …

Overall Nasalance Versus Trimmed Selection Of Stable Syllable Repetition, Jackson Peebles

Honors Theses

Objective: To evaluate the difference between nasalance measured using overall nasalance for the full set of syllable repetitions in a speech sample contrasted with syllable repetitions selected (trimmed) from the overall sample.

Method: Participants included 24 males and 34 females between 18 and 30 years of age who participated in a normative study of nasalance in Michigan’s lower peninsula. Participants produced 14 syllable stimuli. Each syllable sequence was repeated at least 8 times. Three trials of each repetition were recorded together with other speech stimuli. Overall nasalance was calculated for each syllable repetition sequence (whole) and compared with the mean …

A Model For Fixing Identification Evidence After Perry V. New Hampshire, Robert Couch

Michigan Law Review

Mistaken eyewitness identifications are the leading cause of wrongful convictions. In 1977, a time when the problems with eyewitness identifications had been acknowledged but were not yet completely understood, the Supreme Court announced a test designed to exclude unreliable eyewitness evidence. This standard has proven inadequate to protect against mistaken identifications. Despite voluminous scientific studies on the failings of eyewitness identification evidence and the growing number of DNA exonerations, the Supreme Court's outdated reliability test remains in place today. In 2012, in Perry v. New Hampshire, the Supreme Court commented on its standard for evaluating eyewitness evidence for the first …

Congenericity And The Measurement Of Interpersonal Communication Constructs: A Confirmatory Factor Analytic Test Of Four Measures, Paola Pascual-Ferra

Open Access Dissertations

It has long been known that measures can vary in the degree to which they are congeneric. The criteria for congenericity are important because (1) estimates of scale reliability such as those generated by Cronbach’s alpha greatly overestimate the reliability of noncongeneric measures, and (2) error covariances indicate that latent variable(s) other than the construct of interest contribute to item scores, thereby producing confounded measurements. Despite the observation that most measures in psychological research, which are similar to many communication measures, are noncongeneric, measures in communication research have been treated as though they are congeneric. In the present study, four …

Bootstrap Interval Estimation Of Reliability Via Coefficient Omega, Miguel A. Padilla, Jasmin Divers

Journal of Modern Applied Statistical Methods

Three different bootstrap confidence intervals (CIs) for coefficient omega were investigated. The CIs were assessed through a simulation study with conditions not previously investigated. All methods performed well; however, the normal theory bootstrap (NTB) CI had the best performance because it had more consistent acceptable coverage under the simulation conditions investigated.

Test-Retest Reliability And Responsiveness Of Gaze Stability And Dynamic Visual Acuity In High School And College Football Players, Denise Kaufman, Mallory Puckett, Mitchell Smith

UNLV Theses, Dissertations, Professional Papers, and Capstones

Objectives: The purpose of this study was to establish reliability and responsiveness of the active dynamic visual acuity test (DVAT) at speeds of 150 to 200 degrees per second (deg/sec) and the gaze stabilization test (GST) in high school and college football players.

Design: Reliability design

Setting, Participants, Main Outcome Measures: A total of 50 high school and college football athletes completed vestibulo-ocular reflex testing using the DVAT and GST in the yaw (horizontal) and pitch (vertical) planes on two separate occasions within 14 days.

Results: Test-retest reliability for the DVAT was good in yaw, Intraclass Correlation Coefficient (ICC) (3,3) …

Counsel's Control Over The Presentation Of Mitigating Evidence During Capital Sentencing, James Michael Blakemore

Michigan Law Review

The Sixth Amendment gives a defendant the right to control his defense and the right to a lawyer's assistance. A lawyer's assistance, however, sometimes interferes with a defendant's control over his case. As a result, the Supreme Court, over time, has had to delineate the spheres of authority that pertain to counsel and defendant respectively. The Court has not yet decisively assigned control over mitigating evidence to either counsel or defendant. This Note argues that counsel should control the presentation of mitigating evidence during capital sentencing. First, and most importantly, decisions concerning the presentation of mitigating evidence are best characterized …

Reliability Analysis Of Low-Silver Bga Spheres Comparing Failure Detection Criteria, Briana Fredericks

Industrial and Manufacturing Engineering

One of the challenges of solder joint reliability tests is estimating the time of failure of the solder joint. Failure criteria should be able to detect solder joint failure as early as possible, while minimizing the probability of false detection. The failure mechanism under study is cracks due to thermal fatigue. The most common method to estimate failure due to cracks is to monitor the resistance during testing, because solder imaging and cross-sectioning methods are destructive. Current industry failure criteria do not adequately demonstrate the relationship between the size of the crack and the resulting change in resistance. This project …

Evaluation Of Malaysian Retail Service Quality, Mohd Roslan Mohd Nor, Zalina Ibrahim, Linda Dana, Ahmad Faisal Mahdi, Mohamad Zaid Mohd Zin, Mohd Anuar Ramli

Mohd Roslan Mohd Nor

In retailing different requirement of service quality in product or services environment required. Some of the retail stores have lack on service quality whereas the salesperson is not well trained, unknowledgeable and rude. This study aims to evaluate the retail service quality from a supermarket in Kuching, Malaysia and sets out to determine what influence customers to shop. This research looks at the five dimensions of retail service quality: the physical aspect, reliability, personal interaction, problem solving and policy. A survey of 200 respondents was conducted and reliability test is measured to represent the dimensions whereas regression test and Pearson …

The Effects Of Geographical Distribution On The Reliability Of Wind Energy, Samuel Martin Fisher, Justin T. Schoof, Christopher Lant, Matthew Therrell

Publications

No abstract provided.

Assessing Reliability And Validity Of The 15-Item Short Version Of The Attitudes Toward Women Scale (Aws) Among Turkish Students, Raquel Delevi, Asli Bugay

Journal of International Women's Studies

The purpose of the present study was to adapt the 15-item short version of Attitude toward Women Scale (AWS) (Spence & Helmreich, 1978) into Turkish by first doing the translation of its items and then by investigating its preliminary psychometric properties. AWS and Bem Sex Role Inventory (BSRI) were administered to Turkish college students. Factor structures, convergent validity, and internal reliability were investigated across two independent samples. Result revealed satisfactory internal reliability, convergent and construct validity for the 12-item short version in both samples, suggesting that the scale can be used as a reliable instrument in the Turkish culture to …

Carbonation Service Life Prediction Of Existing Concrete Viaduct/Bridge Using Time-Dependent Reliability Analysis, Ming-Te Liang, Ran Huang, Shen-Ann Fang

Journal of Marine Science and Technology

This paper examines the predicted carbonation life of an existing concrete viaduct/bridge in the atmospheric environment based on probability and reliability indices. The probability is dependent upon the carbonation rate, carbonation remainder, concrete quality, and concrete cover. The carbonation life is defined as the service life of reinforced concrete (RC) or prestressed concrete (PC) structure at the beginning of time of steel corrosion when concrete cover surfers from carbonation and loses the protection function to steel. The carbonation life is equivalent to the initiation time of corrosion of reinforcement. Both the Chorng-ching viaduct and Wannfwu bridge were offered as illustrative …

Smore Revision: Ignition And User Interface, Arash Mehrparvar

Aerospace Engineering

The Static Methanol Oxygen Rocket Engine (SMORE) has undergone several revisions since its inception. This latest revision aimed to increase startup reliability and user safety in the operation of the rocket. The implementation of maintenance procedures, safeguards in the ignition system, as well as construction of a new control box and redesign of the igniter itself have accomplished these goals while keeping costs down and without modifying the current rocket setup. Startup reliability has increased drastically, so long as all other rocket setup procedures are followed properly. 250 subsequent firings of the rocket have proven an igniter reliability of more …