Digital Commons Network^™

Data-Integrity Aware Stochastic Model For Cascading Failures In Power Grids, Rezoan Ahmed Shuvro, Pankaz Das, Jamir Shariar Jyoti, Joana Abreu, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

The reliable operation of power grids during cascading failures is heavily dependent on the interdependencies between the power grid components and the supporting communications and control networks. Moreover, the system operators' expertise in dealing with cascading failures can play a pivotal role during contingencies. In this paper, a dynamical probabilistic model is developed based on Markov-chains, which captures the dynamics of cascading failures in the power grid. Specifically, a previously developed Markov-chain based model is extended to capture the trade-off between the benefits of having a robust communication infrastructure and its vulnerability from data integrity (e.g., cyber-attacks). State-space reduction of …

Characterizations And Reliability Measures Of The Generalized Log Burr Xii Distribution, Fiaz Ahmad Bhatti, Gholamhossein G. Hamedani, Azeem Ali, Sedigheh Mirzaei Salehabadi, Munir Ahmad

Mathematical and Statistical Science Faculty Research and Publications

In this paper, we derive the generalized log Burr XII (GLBXII) distribution [2] from the generalized Burr-Hatke differential equation. We characterize the GLBXII distribution via innovative techniques. We derive various reliability measures (series and parallel). We also authenticate the potentiality of the GLBXII model via economics applications. The applications of characterizations and reliability measures of the GLBXII distribution in different disciplines of science will be profitable for scientists.

Probabilistic Prediction Model For Rc Bond Failure Mode, Ahmad Soraghi, Qindan Huang

Civil and Environmental Engineering Faculty Research and Publications

Adequate rebar-concrete bonding is crucial to ensure the reliable performance of reinforced concrete (RC) structures. Many factors such as the concrete properties, concrete cover depth, transverse reinforcement, and the presence of corrosion will affect the bond behavior, and consequently, the structural performance. While many prior studies have focused on the influence of the aforementioned factors on the bond strength, the impact of these factors on the bond failure mode has not been thoroughly investigated. A probabilistic bond failure mode prediction model that considers various influencing factors including loading type and corrosion is developed in this study. This study uses the …

Spectral Resting-State Eeg (Rseeg) In Chronic Aphasia Is Reliable, Sensitive, And Correlates With Functional Behavior, Sarah Grace Dalton, James F. Cavanagh, Jessica D. Richardson

Speech Pathology and Audiology Faculty Research and Publications

We investigated spectral resting-state EEG in persons with chronic stroke-induced aphasia to determine its reliability, sensitivity, and relationship to functional behaviors. Resting-state EEG has not yet been characterized in this population and was selected given the demonstrated potential of resting-state investigations using other neuroimaging techniques to guide clinical decision-making. Controls and persons with chronic stroke-induced aphasia completed two EEG recording sessions, separated by approximately 1 month, as well as behavioral assessments of language, sensorimotor, and cognitive domains. Power in the classic frequency bands (delta, theta, alpha, and beta) was examined via spectral analysis of resting-state EEG data. Results suggest that …

Quantifying The Impact Of Uncertainty In Embedded Systems Mapping For Noc Based Architectures, Wenkai Guan, Milad Ghorbani Moghaddam, Cristinel Ababei

Electrical and Computer Engineering Faculty Research and Publications

We describe a modeling framework to capture and account for uncertainty in design parameters in embedded systems. We then develop an uncertainty-aware solution to the problem of mapping in embedded systems that uses Network-on-Chip (NoC) based architecture platforms. The problem of mapping is formulated as a multi-objective - reliability, performance, and energy consumption - optimization problem. To solve this problem, we propose a solution based on the NSGA-II genetic algorithm and Monte Carlo simulation techniques. The solution is implemented as a computer-aid design tool that can generate robust 3D Pareto frontiers in the solution space formed by the design objectives …

Cubic Rank Transmuted Modified Burr Iii Distribution: Development, Properties, Characterizations And Applications, Fiaz Ahmad Bhatti, Gholamhossein Hamedani, Seyed Morteza Najibi, Munir Ahmad

Mathematical and Statistical Science Faculty Research and Publications

We propose a lifetime distribution with flexible hazard rate called cubic rank transmuted modified Burr III (CRTMBIII) distribution. We develop the proposed distribution on the basis of the cubic ranking transmutation map. The density function of CRTMBIII is symmetrical, right-skewed, left-skewed, exponential, arc, J and bimodal shaped. The flexible hazard rate of the proposed model can accommodate almost all types of shapes such as unimodal, bimodal, arc, increasing, decreasing, decreasing-increasing-decreasing, inverted bathtub and modified bathtub. To show the importance of proposed model, we present mathematical properties such as moments, incomplete moments, inequality measures, residual life function and stress strength reliability …

Adjustable Flat Layouts For Two-Failure Tolerant Storage Systems, Thomas Schwarz

Computer Science Faculty Research and Publications

Systems suffer component failure at sometimes un-predictable rates. Storage systems are no exception; they add redundancy in order to deal with various types of failures. The additional storage constitutes an important capital and operational cost and needs to be dimensioned appropriately. Unfortunately, storage device failure rates are difficult to predict and change over the lifetime of the system. Large disk-based storage centers provide protection against failure at the level of objects. However, this abstraction makes it difficult to adjust to a batch of devices that fail at a higher than anticipated rate. We propose here a solution that uses large …

New Modified Singh-Maddala Distribution: Development, Properties, Characterizations And Applications, Fiaz Ahmad Bhatti, Gholamhossein G. Hamedani, Mustafa Ç. Korkmaz, Munir Ahmad

Mathematical and Statistical Science Faculty Research and Publications

In this paper, a new five-parameter extended Burr XII model called new modified Singh-Maddala (NMSM) is developed from cumulative hazard function of the modified log extended integrated beta hazard (MLEIBH) model. The NMSM density function is left-skewed, right-skewed and symmetrical. The Lambert W function is used to study descriptive measures based on quantile, moments, and moments of order statistics, incomplete moments, inequality measures and residual life function. Different reliability and uncertainty measures are also theoretically established. The NMSM distribution is characterized via different techniques and its parameters are estimated using maximum likelihood method. The simulation studies are performed on the …

Novel Test Fixture For Characterizing Mems Switch Microcontact Reliability And Performance, Protap Mahanta, Farhana Anwar, Ronald A. Coutu Jr.

Electrical and Computer Engineering Faculty Research and Publications

In microelectromechanical systems (MEMS) switches, the microcontact is crucial in determining reliability and performance. In the past, actual MEMS devices and atomic force microscopes (AFM)/scanning probe microscopes (SPM)/nanoindentation-based test fixtures have been used to collect relevant microcontact data. In this work, we designed a unique microcontact support structure for improved post-mortem analysis. The effects of contact closure timing on various switching conditions (e.g., cold-switching and hot-switching) was investigated with respect to the test signal. Mechanical contact closing time was found to be approximately 1 us for the contact force ranging from 10–900 μN. On the other hand, for the 1 …

Cubic Rank Transmuted Modified Burr Iii Pareto Distribution: Development, Properties, Characterizations And Applications, Fiaz Ahmad Bhatti, Gholamhossein G. Hamedani, Wenhui Sheng, Munir Ahmad

Mathematical and Statistical Science Faculty Research and Publications

In this paper, a flexible lifetime distribution called Cubic rank transmuted modified Burr III-Pareto (CRTMBIII-P) is developed on the basis of the cubic ranking transmutation map. The density function of CRTMBIII-P is arc, exponential, left-skewed, right-skewed and symmetrical shaped. Descriptive measures such as moments, incomplete moments, inequality measures, residual life function and reliability measures are theoretically established. The CRTMBIII-P distribution is characterized via ratio of truncated moments. Parameters of the CRTMBIII-P distribution are estimated using maximum likelihood method. The simulation study for the performance of the maximum likelihood estimates (MLEs) of the parameters of the CRTMBIII-P distribution is carried out. …

On The Modified Burr Xii-Power Distribution: Development, Properties, Characterizations And Applications, Fiaz Ahmad Bhatti, Gholamhossein G. Hamedani, Mustafa Ç. Korkmaz, Munir Ahmad

Mathematical and Statistical Science Faculty Research and Publications

In this paper, a flexible lifetime distribution with increasing, decreasing and bathtub hazard rate called the Modified Burr XII-Power (MBXII-Power) is developed on the basis of the T-X family technique. The density function of the MBXII-Power is arc, exponential, left-skewed, right-skewed, J, reverse-J and symmetrical shaped. Descriptive measures such as moments, moments of order statistics, incomplete moments, inequality measures, residual life functions and reliability measures are theoretically established. The MBXII-Power distribution is characterized via different techniques. Parameters of the MBXII-Power distribution are estimated using maximum likelihood method. The simulation study is performed on the basis of graphical results to see …

On The Generalized Log Burr Iii Distribution: Development, Properties, Characterizations And Applications, Fiaz Ahmad Bhatti, Gholamhossein Hamedani, Azeem Ali, Munir Ahmad

Mathematical and Statistical Science Faculty Research and Publications

In this paper, we present a generalized log Burr III (GLBIII) distribution developed on the basis of a generalized log Pearson differential equation (GLPE). The density function of the GLBIII is exponential, arc, J, reverse-J, bimodal, left-skewed, right- skewed and symmetrical shaped. The hazard rate function of GLBIII distribution has various shapes such as constant, increasing, decreasing, increasing-decreasing, upside- down bathtub and modified bathtub. Descriptive measures such as quantile function, sub- models, ordinary moments, moments of order statistics, incomplete moments, reliability and uncertainty measures are theoretically established. The GLBIII distribution is characterized via different techniques. Parameters of the GLBIII distribution …

On Burr Iii-Pareto Distribution: Development, Properties, Characterizations And Applications, Fiaz Ahmad Bhatti, Gholamhossein G. Hamedani, Mustafa Ç. Korkmaz, Munir Ahmad

Mathematical and Statistical Science Faculty Research and Publications

In this paper, a new four parameter lifetime model with increasing, decreasing, increasing-decreasing, decreasing-increasing-decreasing, modified bathtub, bathtub and inverted bathtub hazard rate function called Burr III-Pareto (BIII-Pareto) is developed on the basis of the T-X family technique. The BIII-Pareto density function is arc, J-shape, reverse J-shape, positively, negatively skewed and symmetrical. Some structural and mathematical properties including moments, moments of order statistics, inequality measures and reliability measures are theoretically established. The BIII-Pareto distribution is characterized via different techniques. Parameters of the BIII-Pareto distribution are estimated using maximum likelihood method. The simulation study for performance of the maximum likelihood estimates (MLEs) …

Systemic Exercise-Induced Hypoalgesia Following Isometric Exercise Reduces Conditioned Pain Modulation, Ali Alsouhibani, Henrik Bjarke Vaegter, Marie K. Hoeger Bement

Physical Therapy Faculty Research and Publications

Objective

Physically active individuals show greater conditioned pain modulation (CPM) compared with less active individuals. Understanding the effects of acute exercise on CPM may allow for a more targeted use of exercise in the management of pain. This study investigated the effects of acute isometric exercise on CPM. In addition, the between-session and within-session reliability of CPM was investigated.

Design

Experimental, randomized crossover study.

Setting

Laboratory at Marquette University.

Subjects

Thirty healthy adults (19.3±1.5 years, 15 males).

Methods

Subjects underwent CPM testing before and after isometric exercise (knee extension, 30% maximum voluntary contraction for three minutes) and quiet rest in …

On Extended Quadratic Hazard Rate Distribution: Development, Properties, Characterizations And Applications, Fiaz Ahmad Bhatti, Gholamhossein G. Hamedani, Wenhui Sheng, Munir Ahmad

Mathematical and Statistical Science Faculty Research and Publications

In this paper, we propose a flexible extended quadratic hazard rate (EQHR) distribution with increasing, decreasing, bathtub and upside-down bathtub hazard rate function. The EQHR density is arc, right-skewed and symmetrical shaped. This distribution is also obtained from compounding mixture distributions. Stochastic orderings, descriptive measures on the basis of quantiles, order statistics and reliability measures are theoretically established. Characterizations of the EQHR distribution are studied via different techniques. Parameters of the EQHR distribution are estimated using the maximum likelihood method. Goodness of fit of this distribution through different methods is studied.

On Modified Burr Xii-Inverse Exponential Distribution: Prop¬Erties, Characterizations And Applications, Fiaz Ahmad Bhatti, Gholamhossein Hamedani, Haitham M. Yousof, Azeem Ali, Munir Ahmad

Mathematical and Statistical Science Faculty Research and Publications

In this paper, a flexible lifetime distribution with increasing, increasing and decreasing and modified bathtub hazard rate called Modified Burr XII-Inverse Exponential (MBXII-IE) is introduced. The density function of MBXII-IE has exponential, left-skewed, right-skewed and symmetrical shapes. Descriptive measures such as moments, moments of order statistics, incomplete moments, inequality measures, residual life function and reliability measures are theoretically established. The MBXII-IE distribution is characterized via different techniques. Parameters of MBXII-IE distribution are estimated using maximum likelihood method. The simulation study is performed to illustrate the performance of the Maximum Likelihood Estimates (MLEs) of the parameters of the MBXII-IE distribution. The …

The Measurement Properties Of The Spence Children's Anxiety Scale‐Parent Version In A Large International Pooled Sample Of Young People With Autism Spectrum Disorder, Iliana Magiati, Jian Wei Lerh, Matthew J. Hollocks, Mirko Uljarevic, Jacqui Rodgers, Helen Mcconachie, Ann Ozsivadjian, Mikle South, Amy V. Van Hecke, Antonio Hardan, Robin Libove, Susan Leekam, Emily Simonoff

Psychology Faculty Research and Publications

Anxiety‐related difficulties are common in ASD, but measuring anxiety reliably and validly is challenging. Despite an increasing number of studies, there is no clear agreement on which existing anxiety measure is more psychometrically sound and what is the factor structure of anxiety in ASD. The present study examined the internal consistency, convergent, divergent, and discriminant validity, as well as the factor structure of the Spence Children's Anxiety Scale‐Parent Version (SCAS‐P), in a large international pooled sample of 870 caregivers of youth with ASD from 12 studies in the United Kingdom, United States, and Singapore who completed the SCAS‐P. Most were …

Benefits Of Considering More Than Temperature Acceleration For Gan Hemt Life Testing, Ronald A. Coutu Jr., Robert A. Lake, Bradley D. Christiansen, Eric R. Heller, Christopher A. Bozada, Brian S. Poling, Glen D. Via, James P. Theimer, Stephen E. Tetlak, Ramakrishna Vetury, Jeffrey B. Shealy

Electrical and Computer Engineering Faculty Research and Publications

The purpose of this work was to investigate the validity of Arrhenius accelerated-life testing when applied to gallium nitride (GaN) high electron mobility transistors (HEMT) lifetime assessments, where the standard assumption is that only critical stressor is temperature, which is derived from operating power, device channel-case, thermal resistance, and baseplate temperature. We found that power or temperature alone could not explain difference in observed degradation, and that accelerated life tests employed by industry can benefit by considering the impact of accelerating factors besides temperature. Specifically, we found that the voltage used to reach a desired power dissipation is important, and …

Readiness For Hospital Discharge Scale For Older People: Psychometric Testing And Short Form Development With A Three Country Sample, Cédric Mabire, Alice Coffey, Marianne E. Weiss

College of Nursing Faculty Research and Publications

Aim

To develop and psychometrically test Readiness for Hospital Discharge Scale for older people and to reduce the scale to a more practical short form.

Background

The Readiness for Hospital Discharge Scale is the only available and validated scale measuring patients' perceived readiness just prior to discharge.

Design

Secondary analysis of hospital studies data from three countries.

Method

Data were collected between 2008–2012. The study sample comprised 998 medical-surgical older patients. Factor analysis was undertaken to identify the factor structure of the Readiness for Hospital Discharge Scale. Group comparisons for construct validity and predictive validity for readmission were also conducted. …

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 …

Intra- And Inter-Examiner Reliability Of Direct Facial Soft Tissue Measurements Using Digital Calipers, Nikolay Mollov, Jose A. Bosio, Jessica E. Pruszynski, Thomas S. Wirtz

School of Dentistry Faculty Research and Publications

Background: The objective of this study is to determine if facial soft tissue measurements using digital calipers can be reliably taken by the same examiner and by a large group of examiners.

Materials and Methods: Ten examiners performed a set of 18 in-clinic measurements on 10 female and 10 male dental students using a digital caliper twice over a 3-week period. The intra-class correlation coefficient and the Shrout-Fleiss method were used for the statistical analysis.

Results: Anthropometric intra-examiner reliability was high for all measurements (none fell below R = 0.934). However, inter-examiner reliability exhibited a wide range of values, some …

Performance And Reliability Of Non-Markovian Heterogeneous Distributed Computing Systems, Jorge E. Pezoa, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

Average service time, quality-of-service (QoS), and service reliability associated with heterogeneous parallel and distributed computing systems (DCSs) are analytically characterized in a realistic setting for which tangible, stochastic communication delays are present with nonexponential distributions. The departure from the traditionally assumed exponential distributions for event times, such as task-execution times, communication arrival times and load-transfer delays, gives rise to a non-Markovian dynamical problem for which a novel age dependent, renewal-based distributed queuing model is developed. Numerical examples offered by the model shed light on the operational and system settings for which the Markovian setting, resulting from employing an exponential-distribution assumption …

Psychometric Testing Of The Children's Resourcefulness Scale, Jaclene A. Zauszniewski, Abir K. Bekhet, Elizabeth Bonham

College of Nursing Faculty Research and Publications

PROBLEM: Resourcefulness is known to reduce depression in adults, but its effects on children are less well known, possibly for lack of a psychometrically sound measure.

METHODS: This study examined the reliability and validity of the 32-item Children's Self-Control Scale (C-SCS), which measures resourcefulness, in 122 school-aged children.

FINDINGS: Standard scale refinement methods produced a 10-item scale with α = .72 and correlations with the C-SCS (r = .86), positive thoughts (r = .38), and depressive symptoms (r = –.32). Factor analysis revealed two factors: problem-solving and delay of gratification.

CONCLUSIONS: The 10-item scale may be …

Injecting, Controlling, And Storing Magnetic Domain Walls In Ferromagnetic Nanowires, Andrew Kunz, Jonathan D. Priem, Sarah C. Reiff

Physics Faculty Research and Publications

Domain walls in ferromagnetic nanowires are important for proposed devices in recording, logic, and sensing. The realization of such devices depends in part on the ability to quickly and accurately control the domain wall from creation until placement. Using micromagnetic computer simulation we demonstrate how a combination of externally applied magnetic fields is used to quickly inject, move, and accurately place multiple domain walls within a single wire for potential recording and logical operations. The use of a magnetic field component applied perpendicular to the principle domain wall driving field is found to be critical for increased speed and reliability. …

Dynamic Stabilization During The Landing Phase Of Plyometric Exercises, Erich Petushek, Luke Garceau, Tyler Vanderzanden, Brad Wurm, Christina Feldmann, William Ebben

Exercise Science Faculty Research and Publications

This study examined the differences in and the reliability of time to stabilization (TTS) of several plyometric exercises. Twenty six men performed a variety of plyometric exercises representing a continuum of intensities of landing instability, including line hops, cone hops, squat jumps, tuck jumps, countermovement jumps, dumbbell countermovement jumps, and single leg countermovement jumps on a force platform. A repeated measures ANOVA with Bonferroni post hoc corrections was used to evaluate the differences in TTS between plyometric exercises. Practitioners who use plyometrics to train dynamic stability and balance should create programs that progress the intensity of the exercises based on …

Psychometric Properties Of The Readiness For Hospital Discharge Scale, Marianne Weiss, Linda Piacentine

College of Nursing Faculty Research and Publications

The purpose of the study was to assess the psychometrics properties of the Readiness for Hospital Discharge Scale (RHDS), a 23-item instrument that measures patients' perception of readiness for discharge. Data were obtained from 356 respondents from two urban tertiary medical centers (adult and children's) in the midwestern United States who were participants in a larger study of predictors and outcomes of readiness for hospital discharge. Confirmatory factor analysis, contrasted group comparisons, and predictive validity testing supported the 4-factor structure and construct validity of the instrument. Following deletion of two poorly performing items, Cronbach's alpha for the revised 21item scale …

Validity And Reliability Of The Perceived Readiness For Discharge After Birth Scale, Marianne Weiss, Polly Ryan, Lisa Lokken

College of Nursing Faculty Research and Publications

Objective: To assess the psychometric properties of a scale measuring mothers’ perceptions of readiness for discharge after birth.

Design: Psychometric analyses including construct validity using factor analysis and known groups comparisons, predictive validity, and reliability. Data were collected at discharge and 6 weeks postdischarge. Setting: Tertiary-level perinatal center in the Midwestern United States. Participants: 1,462 postpartum mothers. Intervention: None. Main Outcome Measures: Perceived Readiness for Discharge After Birth Scale scores; subscale scores for personal status and knowledge factors.'

Results: Exploratory and confirmatory factor analyses indicated that the scale contained two factors. Perceived Readiness for Discharge After Birth Scale scores were …

Psychometric Evaluation Of The Shared Care Instrument In A Sample Of Home Health Care Family Dyads, Margaret Sebern

College of Nursing Faculty Research and Publications

Researchers have studied negative effects of caregiving on a family caregiver; however, less is known about positive aspects of exchanging assistance for both members of a family caregiving dyad. In a previous naturalistic inquiry the author indentified a basis for studying caregiving interactions was a construct called shared care. The three components of shared care identified in the naturalistic inquiry were communication, decision making, and reciprocity. The Shared Care Instrument (SCI) was developed to measure the construct. The purpose of this study was to assess the psychometric properties of the SCI, and to assess its construct and criterion-related validity. A …

The Market Attitudes Inventory: The Development And Testing Of Reliability And Validity, Noreen Lephardt, Charles Breeden

Economics Faculty Research and Publications

In this article we report the development of a 22-statement survey that measures attitudes towards the market system. We report on the testing of the Market Attitude Inventory (MAI) for reliability and validity. Mean scores on the instrument are reported for a random sample of Midwest high school social studies teachers. We conclude that the MAI is a valid and reliable instrument. The MAI has applications in research, educational outcome assessment, and teaching pedagogy for the measurement and evaluation of attitudes and values towards the workings of the market system in the US.

Assessing Student Exposure To And Use Of Computer Technologies Through An Examination Of Course Syllabi, Michael B. Madson, Timothy P. Melchert, Joan Whipp

College of Education Faculty Research and Publications

A syllabus analysis instrument was developed to assist program evaluators, administrators and faculty in the identification of skills that students use as they complete their college coursework. While this instrument can be tailored for use with a variety of learning domains, we used it to assess students' use of and exposure to computer technology skills. The reliability and validity of the instrument was examined through an analysis of 88 syllabi from courses within the teacher education program and the core curriculum at a private Midwest US university. Results indicate that the instrument has good inter‐rater reliability and ratings by and …