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2017

Old Dominion University

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Articles 31 - 60 of 113

Full-Text Articles in Engineering

Biophysical Tools To Study Cellular Mechanotransduction, Ismeel Muhamed, Farhan Chowdhury, Venkat Maruthamuthu Feb 2017

Biophysical Tools To Study Cellular Mechanotransduction, Ismeel Muhamed, Farhan Chowdhury, Venkat Maruthamuthu

Mechanical & Aerospace Engineering Faculty Publications

The cell membrane is the interface that volumetrically isolates cellular components from the cell's environment. Proteins embedded within and on the membrane have varied biological functions: reception of external biochemical signals, as membrane channels, amplification and regulation of chemical signals through secondary messenger molecules, controlled exocytosis, endocytosis, phagocytosis, organized recruitment and sequestration of cytosolic complex proteins, cell division processes, organization of the cytoskeleton and more. The membrane's bioelectrical role is enabled by the physiologically controlled release and accumulation of electrochemical potential modulating molecules across the membrane through specialized ion channels (e.g., Na, Ca2+, K channels). …


Preface To Special Topic: A Tribute To John Lumley, Kiran Bhaganagar, Thomas B. Gatski, William K. George Feb 2017

Preface To Special Topic: A Tribute To John Lumley, Kiran Bhaganagar, Thomas B. Gatski, William K. George

CCPO Publications

This Special Topic Section is dedicated to the life and memory of John Leask Lumley(1930-2015), professor and scientist extraordinaire.


Augmenting Bottom-Up Metamodels With Predicates, Ross J. Gore, Saikou Diallo, Christopher Lynch, Jose Padilla Jan 2017

Augmenting Bottom-Up Metamodels With Predicates, Ross J. Gore, Saikou Diallo, Christopher Lynch, Jose Padilla

VMASC Publications

Metamodeling refers to modeling a model. There are two metamodeling approaches for ABMs: (1) top-down and (2) bottom-up. The top down approach enables users to decompose high-level mental models into behaviors and interactions of agents. In contrast, the bottom-up approach constructs a relatively small, simple model that approximates the structure and outcomes of a dataset gathered fromthe runs of an ABM. The bottom-up metamodel makes behavior of the ABM comprehensible and exploratory analyses feasible. Formost users the construction of a bottom-up metamodel entails: (1) creating an experimental design, (2) running the simulation for all cases specified by the design, (3) …


Data-Driven Spatial Modeling For Quantifying Networkwide Resilience In The Aftermath Of Hurricanes Irene And Sandy, Yuan Zhu, Kun Xie, Kaan Ozbay, Fan Zuo, Hong Yang Jan 2017

Data-Driven Spatial Modeling For Quantifying Networkwide Resilience In The Aftermath Of Hurricanes Irene And Sandy, Yuan Zhu, Kun Xie, Kaan Ozbay, Fan Zuo, Hong Yang

Computational Modeling & Simulation Engineering Faculty Publications

In recent years, the New York City metropolitan area was hit by two major hurricanes, Irene and Sandy. These extreme weather events disrupted and devastated the transportation infrastructure, including road and subway networks. As an extension of the authors' recent research on this topic, this study explored the spatial patterns of infrastructure resilience in New York City with the use of taxi and subway ridership data. Neighborhood tabulation areas were used as the units of analysis. The recovery curve of each neighborhood tabulation area was modeled with the logistic function to quantify the resilience of road and subway systems. Moran's …


Controlling The Error On Target Motion Through Real-Time Mesh Adaptation: Applications To Deep Brain Stimulation, Huu Phuoc Bui, Satyendra Tomar, Hadrien Courtecuisse, M. Audette, Stéphane Cotin, Stéphane P.A. Bordas Jan 2017

Controlling The Error On Target Motion Through Real-Time Mesh Adaptation: Applications To Deep Brain Stimulation, Huu Phuoc Bui, Satyendra Tomar, Hadrien Courtecuisse, M. Audette, Stéphane Cotin, Stéphane P.A. Bordas

Computational Modeling & Simulation Engineering Faculty Publications

We present an error-controlled mesh refinement procedure for needle insertion simulation and apply it to the simulation of electrode implantation for deep brain stimulation, including brain shift.

Our approach enables to control the error in the computation of the displacement and stress fields around the needle tip and needle shaft by suitably refining the mesh, whilst maintaining a coarser mesh in other parts of the domain.

We demonstrate through academic and practical examples that our approach increases the accuracy of the displacement and stress fields around the needle without increasing the computational expense. This enables real-time simulations.

The proposed methodology …


Impact Of A Localized Lean Six Sigma Implementation On Overall Patient Safety And Process Efficiency, Luvianca Gil, Pilar Pazos, Mamadou Seck, Rolando Delaguila Jan 2017

Impact Of A Localized Lean Six Sigma Implementation On Overall Patient Safety And Process Efficiency, Luvianca Gil, Pilar Pazos, Mamadou Seck, Rolando Delaguila

Engineering Management & Systems Engineering Faculty Publications

Continuous quality improvement tools have caught the attention of the Health Care Industry as a solution to process efficiency, patient safety and cost reduction. This research explores the impact of a Lean Six Sigma (LSS) process improvement initiative in overall process efficiency and patient safety in two Labor and Delivery (L+D) units of two large hospital providers. This study focuses on the application of modeling and simulation methodology to investigate the influence of a localized process improvement intervention on the overall L+D unit output, by considering patient flow, system capacity and unit performance. The simulation models capacity profiles and patient …


Electrotransfer Of Plasmid Dna Radiosensitizes B16f10 Tumors Through Activation Of Immune Response, Monika Savarin, Urska Kamensek, Maja Cemazar, Richard Heller, Gregor Sersa Jan 2017

Electrotransfer Of Plasmid Dna Radiosensitizes B16f10 Tumors Through Activation Of Immune Response, Monika Savarin, Urska Kamensek, Maja Cemazar, Richard Heller, Gregor Sersa

Bioelectrics Publications

Background. Tumor irradiation combined with adjuvant treatments, either vascular targeted or immunomodulatory, is under intense investigation. Gene electrotransfer of therapeutic genes is one of these approaches. The aim of this study was to determine, whether gene electrotransfer of plasmid encoding shRNA for silencing endoglin, with vascular targeted effectiveness, can radiosensitize melanoma B16F10 tumors.

Materials and methods. The murine melanoma Bl6F10 tumors, growing on the back of C57BI/6 mice, were treated by triple gene electrotransfer and irradiation. The antitumor effect was evaluated by determination of tumor growth delay and proportion of tumor free mice. Furthermore, histological analysis of tumors (necrosis, apoptosis, …


Biochemical And Histological Differences Between Costal And Articular Cartilages, Michael W. Stacey Jan 2017

Biochemical And Histological Differences Between Costal And Articular Cartilages, Michael W. Stacey

Bioelectrics Publications

Biologically, costal cartilage is an understudied tissue type and much is yet to be learned regarding underlying mechanisms related to form and function, and how these relate to disease states, specifically chest wall deformity. Chest wall deformities have a component of inheritance, implying underlying genetic causes; however the complexity of inheritance suggests multiple genetic components. At our Centre investigations were performed on gene expression of key select genes from costal cartilage removed at surgery of patients with chest wall deformity to show high expression of decorin, a key player in collagen fiber formation and growth. Also, the degree of tissue …


Electrosensitization Increases Antitumor Effectiveness Of Nanosecond Pulsed Electric Fields In Vivo, Claudia Muratori, Andrei G. Pakhomov, Loree Heller, Maura Casciola, Elena Gianulis, Sergey Grigoryev, Shu Xiao, Olga N. Pakhomova Jan 2017

Electrosensitization Increases Antitumor Effectiveness Of Nanosecond Pulsed Electric Fields In Vivo, Claudia Muratori, Andrei G. Pakhomov, Loree Heller, Maura Casciola, Elena Gianulis, Sergey Grigoryev, Shu Xiao, Olga N. Pakhomova

Bioelectrics Publications

Nanosecond pulsed electric fields are emerging as a new modality for tissue and tumor ablation. We previously reported that cells exposed to pulsed electric fields develop hypersensitivity to subsequent pulsed electric field applications. This phenomenon, named electrosensitization, is evoked by splitting the pulsed electric field treatment in fractions (split-dose treatments) and causes in vitro a 2- to 3-fold increase in cytotoxicity. The aim of this study was to show the benefit of split-dose treatments for in vivo tumor ablation by nanosecond pulsed electric field. KLN 205 squamous carcinoma cells were embedded in an agarose gel or grown subcutaneously as tumors …


An Integrated Curriculum For Technical Writing In Higher Education In China, Feifei Zhong, Gene Hou Jan 2017

An Integrated Curriculum For Technical Writing In Higher Education In China, Feifei Zhong, Gene Hou

Mechanical & Aerospace Engineering Faculty Publications

This study aims to develop an effective curriculum plan to improve technical writing in higher education in China. The paper first investigated the deficiency in the curriculum design in China for English technical writing by comparing the required courses offered in Southwest Jiaotong University (SWJTU) in China with those in Old Dominion University (ODU) in US. Questionnaires and interviews were then conducted among studying abroad Chinese students, visiting scholars, English as Second Language (ESL) instructors as well as engineering professors. The collected data revealed that the oversea Chinese students were struggled more with higher order concerns in writing than lower …


Comparing An Atomic Model Or Structure To A Corresponding Cryo-Electron Microscopy Image At The Central Axis Of A Helix, Stephanie Zeil, Julio Kovacs, Willy Wriggers, Jing He Jan 2017

Comparing An Atomic Model Or Structure To A Corresponding Cryo-Electron Microscopy Image At The Central Axis Of A Helix, Stephanie Zeil, Julio Kovacs, Willy Wriggers, Jing He

Computer Science Faculty Publications

Three-dimensional density maps of biological specimens from cryo-electron microscopy (cryo-EM) can be interpreted in the form of atomic models that are modeled into the density, or they can be compared to known atomic structures. When the central axis of a helix is detectable in a cryo-EM density map, it is possible to quantify the agreement between this central axis and a central axis calculated from the atomic model or structure. We propose a novel arc-length association method to compare the two axes reliably. This method was applied to 79 helices in simulated density maps and six case studies using cryo-EM …


A Method For Key Performance Indicator Assessment In Manufacturing Organizations, Patrick Hester, Barry Ezell, Andrew Collins, John Horst, Kaleen Lawsure Jan 2017

A Method For Key Performance Indicator Assessment In Manufacturing Organizations, Patrick Hester, Barry Ezell, Andrew Collins, John Horst, Kaleen Lawsure

VMASC Publications

Key Performance Indicators (KPIs) are an essential element of an organization’s ability to monitor its strategic health, helping to ensure the strategic goals of the organization are achieved. However, KPI assessment and improvement is often an ad hoc and consultant-driven process rather than one undertaken using scientific principles. This paper outlines the development and subsequent deployment of a method for KPI assessment founded in scholarly literature and balancing practitioner concerns for ease of use. The proposed method draws heavily on organizational stakeholder involvement at varying levels throughout the KPI assessment process, improving current methods by introducing a mathematical foundation based …


A Systems Theoretic-Based Framework To Discover Pathologies In Acquisition System Governance, Charles B. Keating, Joseph M. Bradley, Polinpapilinho F. Katina, Ra'ed M. Jaradat Jan 2017

A Systems Theoretic-Based Framework To Discover Pathologies In Acquisition System Governance, Charles B. Keating, Joseph M. Bradley, Polinpapilinho F. Katina, Ra'ed M. Jaradat

Engineering Management & Systems Engineering Faculty Publications

The acquisition field continues to face increasing pressures to perform under conditions of escalating complexity, uncertainty, and ambiguity. These conditions suggest that traditional approaches, practices, and acquisition technologies might be incongruent with support demands for acquisition practitioners. This research is focused on exploiting and extending recent developments in Complex System Governance (CSG) to advance the acquisition field. CSG is focused on the design, execution, and evolution of fundamental system functions necessary for control, communications, coordination, and integration of complex systems (e.g., acquisition). CSG is based in Systems Theory (fundamental laws governing complex systems), Management Cybernetics (the science of effective system …


Flipped Classroom As Blended Learning In A Fluid Mechanics Course In Engineering Technology, Orlando M. Ayala, Otilia Popescu, Vukica M. Jovanovic Jan 2017

Flipped Classroom As Blended Learning In A Fluid Mechanics Course In Engineering Technology, Orlando M. Ayala, Otilia Popescu, Vukica M. Jovanovic

Engineering Technology Faculty Publications

Flipped classroom has gained attention in recent years as a teaching method in which the time allocated for introducing new concepts and the time used for practicing them are inverted, in order to provide more time for problem based learning and class interaction under direct supervision of the instructor. The implementation of this teaching method is comprised of two main components, the pre-class activities, which consist of individual student work and are largely based on pre-recorded videos, and in-class activities, which are group activities supervised by the instructor. This paper discusses the implementation of the flipped classroom method in a …


Developing A Faculty Learning Community To Support Writing Across Different Stem Disciplines, Vukica M. Jovanovic, Denise Tombolato-Terzic, Daniel P. Richards, Pilar Pazos, Megan Mckittrick, Julia Romberger, Otilia Popescu Jan 2017

Developing A Faculty Learning Community To Support Writing Across Different Stem Disciplines, Vukica M. Jovanovic, Denise Tombolato-Terzic, Daniel P. Richards, Pilar Pazos, Megan Mckittrick, Julia Romberger, Otilia Popescu

Engineering Technology Faculty Publications

Writing to learn is one of the very important pedagogical strategies in a variety of disciplines. This concept is not specifically addressed in the majority of engineering courses. Hence, university initiatives such as the Quality Enhancement Plan (QEP), emerging out of accreditation and institutional assessments, are focusing on infusing scholarship from other disciplines (in this case English) for the purpose of student learning improvement. Engineering and Science programs do include various courses in English Composition as the part of the curriculum; however, writing is not embedded in all discipline-specific courses at the upper-division level. The program outlined here focuses on …


Unite 3d Rover Summer Workshop: An Overview And Assessment, Steve C. Hsiung, Walter F. Deal, Francis Tuluri Jan 2017

Unite 3d Rover Summer Workshop: An Overview And Assessment, Steve C. Hsiung, Walter F. Deal, Francis Tuluri

Engineering Technology Faculty Publications

The article offers information about UNITE, a program sponsored by the U.S. Army Educational Outreach Program (AEOP, 2015). It mentions that the STEM Enrichment Activities of AEOP are designed to spark student interest in science, technology, engineering, and mathematics (STEM) especially among the underserved and those in earlier grades and educators by providing exciting, engaging, interactive, hands-on STEM experiences (USAEOP).


Impact Of Clip Connection And Insulation Thickness On Bracing Of Purlins In Standing Seam Roof Systems, Michael W. Seek, Daniel Mclaughlin Jan 2017

Impact Of Clip Connection And Insulation Thickness On Bracing Of Purlins In Standing Seam Roof Systems, Michael W. Seek, Daniel Mclaughlin

Engineering Technology Faculty Publications

The flexural strength of purlins in standing seam roof systems is highly dependent upon the extent to which the sheathing provides lateral and torsional restraint. Typical models to predict the restraint provided by the sheathing assume that the plane of lateral resistance occurs at the top flange of the purlin. In reality, depending on the configuration of the clip and the amount of insulation located between the purlin and the clip, the plane of lateral resistance and corresponding center of rotation shifts above the top flange. This distance, referred to as the effective standoff, is important to evaluate the effectiveness …


Error Aggregation In The Reengineering Process From 3d Scanning To Printing, Jennifer G. Michaeli, Matthew C. Degroff, Roman C. Roxas Jan 2017

Error Aggregation In The Reengineering Process From 3d Scanning To Printing, Jennifer G. Michaeli, Matthew C. Degroff, Roman C. Roxas

Engineering Technology Faculty Publications

This work aims to study the aggregation of dimensional errors in the reengineering processes using 3D scanning and printing without initial design drawings. A 57-tooth spur gear is used as an example to facilitate the discussion. Two approaches are investigated. The first one builds the gear model based upon measurement taken from a caliper, and the second approach uses a 3D scanner to collect geometry data. Dimensional errors in each stage of these two approaches are investigated. Particular attention is paid to the geometry data flow in the reengineering process from data acquisition and editing to model construction. Recommendations are …


Power Budgets For Cubesat Radios To Support Ground Communications And Inter-Satellite Links, Otilia Popescu Jan 2017

Power Budgets For Cubesat Radios To Support Ground Communications And Inter-Satellite Links, Otilia Popescu

Engineering Technology Faculty Publications

CubeSats are a class of pico-satellites that have emerged over the past decade as a cost-effective alternative to the traditional large satellites to provide space experimentation capabilities to universities and other types of small enterprises, which otherwise would be unable to carry them out due to cost constraints. An important consideration when planning CubeSat missions is the power budget required by the radio communication subsystem, which enables a CubeSat to exchange information with ground stations and/or other CubeSats in orbit. The power that a CubeSat can dedicate to the communication subsystem is limited by the hard constraints on the total …


Institutionalizing Continuous Improvement Plan In An Engineering Technology Department- Closing The Loop, Alok K. Verma, Stephanie G. Adams, Cheng Y. Lin, Nestor Escobales, Isaac L. Flory Iv Jan 2017

Institutionalizing Continuous Improvement Plan In An Engineering Technology Department- Closing The Loop, Alok K. Verma, Stephanie G. Adams, Cheng Y. Lin, Nestor Escobales, Isaac L. Flory Iv

Engineering Technology Faculty Publications

Continuous improvement is a corner stone of a quality engineering or engineering technology program. Accreditation Board of Engineering and Technology requires that a well-planned and implemented continuous improvement plan should be in place. The ABET 2015-16 Criterion 4 Continuous Improvement1 states: "The program must regularly use appropriate, documented processes for assessing and evaluating the extent to which the student outcomes are being attained. The results of these evaluations must be systematically utilized as input for the continuous improvement of the program. Other available information may also be used to assist in the continuous improvement of the program." A successful continuous …


Integrative Experiences Through Modeling And Simulation Of Mechatronic Systems, Mileta Tomovic, Cynthia Tomovic, Vukica M. Jovanovic, Cheng Y. Lin, Nan Yao, Petros J. Katsioloudis Jan 2017

Integrative Experiences Through Modeling And Simulation Of Mechatronic Systems, Mileta Tomovic, Cynthia Tomovic, Vukica M. Jovanovic, Cheng Y. Lin, Nan Yao, Petros J. Katsioloudis

Engineering Technology Faculty Publications

Learning is integrative lifelong process which requires continuous refreshing of old material and learning new material. This principle holds also for student experiences during their undergraduate studies. Students learn new material throughout their studies, and they may or may not have opportunity to use the material in different context and at different levels. As a result some of the acquired knowledge may be forgotten by the time student graduates or it may not be placed in the context of the overall program outcomes, thus material presented may not seem to have relevance to student's career. An effective method to address …


Learning Module On Electric Motors Modeling, Control, And Testing (Lm-Emmct), Ana Djuric, Vukica M. Jovanovic, Ece Yaprak, Wen Chen Jan 2017

Learning Module On Electric Motors Modeling, Control, And Testing (Lm-Emmct), Ana Djuric, Vukica M. Jovanovic, Ece Yaprak, Wen Chen

Engineering Technology Faculty Publications

The objective of this paper is to develop and integrate a learning module on Electric Motors Modeling, Control and Testing (EMMCT) into the Electrical Engineering Technology (EET) and Mechanical Engineering Technology (MET) programs. Preparing future engineers to work in highly automated production requires proper education and training in mechatronics theory and applications. Although Engineering Technology programs at various universities offer various courses related to the controls, electrical motors, and automation, they are not including the same methods when it comes to the selection of appropriate electrical motor for a specific application in mechatronic system. MET student do have exposure to …


Integrating Idef0 Into A Systems Framework For Statistical Engineering, Teddy Steven Cotter Jan 2017

Integrating Idef0 Into A Systems Framework For Statistical Engineering, Teddy Steven Cotter

Engineering Management & Systems Engineering Faculty Publications

Driven by a growing requirement during the 21st century for the integration of rigorous statistical analyses in engineering research, there has been a movement within the statistics and quality communities to evolve a unified statistical engineering body of knowledge (Horel and Snee, 2010; Anderson-Cook, 2012). Outside of the 2014 Statistical Engineering Agreement among the ASQ Statistics Division, DOT&E, NASA, and IDA, there has been little formal progress toward this goal since the May 2011 NASA Symposium on Statistical Engineering in Williamsburg Virginia. In the ASEM-IAC 2012, Cotter (2012) identified the gaps in knowledge that statistical engineering needs to address, explored …


Systemic Intervention For Complex System Governance Development, Charles B. Keating, Polinpapilinho F. Katina,, John C. Pyne, Ra’Ed M. Jaradat Jan 2017

Systemic Intervention For Complex System Governance Development, Charles B. Keating, Polinpapilinho F. Katina,, John C. Pyne, Ra’Ed M. Jaradat

Engineering Management & Systems Engineering Faculty Publications

This paper explores the issues related to systemic intervention for Complex System Governance (CSG) development. Systemic intervention seeks to intentionally engage a system to influence trajectory or outcomes. CSG is an emerging field focused on the design, execution, and evolution of the functions necessary to provide continued system performance (stability) in the midst of incessant turbulence and increasing complexity. Integral to this field is the necessity to ‘intervene’ in a complex system to enhance system behavior, structure, or performance. Arguably, system interventions have an unremarkable record of success, ranging from declared success in improving a situation (system) to abysmal failure …


Industrial Wireless Sensor Networks 2016, Qindong Sun, Schancang Li, Shanshan Zhao, Hongjian Sun, Li Xu, Arumugam Nallamathan Jan 2017

Industrial Wireless Sensor Networks 2016, Qindong Sun, Schancang Li, Shanshan Zhao, Hongjian Sun, Li Xu, Arumugam Nallamathan

Information Technology & Decision Sciences Faculty Publications

The industrial wireless sensor network (IWSN) is the next frontier in the Industrial Internet of Things (IIoT), which is able to help industrial organizations to gain competitive advantages in industrial manufacturing markets by increasing productivity, reducing the costs, developing new products and services, and deploying new business models.


Semantic Inference On Clinical Documents: Combining Machine Learning Algorithms With An Inference Engine For Effective Clinical Diagnosis And Treatment, Shuo Yang, Ran Wei, Jingzhi Guo, Lida Xu Jan 2017

Semantic Inference On Clinical Documents: Combining Machine Learning Algorithms With An Inference Engine For Effective Clinical Diagnosis And Treatment, Shuo Yang, Ran Wei, Jingzhi Guo, Lida Xu

Information Technology & Decision Sciences Faculty Publications

Clinical practice calls for reliable diagnosis and optimized treatment. However, human errors in health care remain a severe issue even in industrialized countries. The application of clinical decision support systems (CDSS) casts light on this problem. However, given the great improvement in CDSS over the past several years, challenges to their wide-scale application are still present, including: 1) decision making of CDSS is complicated by the complexity of the data regarding human physiology and pathology, which could render the whole process more time-consuming by loading big data related to patients; and 2) information incompatibility among different health information systems (HIS) …


Qos Recommendation In Cloud Services, Xianrong Zheng, Li Da Xu, Sheng Chai Jan 2017

Qos Recommendation In Cloud Services, Xianrong Zheng, Li Da Xu, Sheng Chai

Information Technology & Decision Sciences Faculty Publications

As cloud computing becomes increasingly popular, cloud providers compete to offer the same or similar services over the Internet. Quality of service (QoS), which describes how well a service is performed, is an important differentiator among functionally equivalent services. It can help a firm to satisfy and win its customers. As a result, how to assist cloud providers to promote their services and cloud consumers to identify services that meet their QoS requirements becomes an important problem. In this paper, we argue for QoS-based cloud service recommendation, and propose a collaborative filtering approach using the Spearman coefficient to recommend cloud …


Measuring Space Radiation Shielding Effectiveness, Amir Bahadori, Edward Semones, Michael Ewert, James Broyan, Steven Walker Jan 2017

Measuring Space Radiation Shielding Effectiveness, Amir Bahadori, Edward Semones, Michael Ewert, James Broyan, Steven Walker

Mathematics & Statistics Faculty Publications

Passive radiation shielding is one strategy to mitigate the problem of space radiation exposure. While space vehicles are constructed largely of aluminum, polyethylene has been demonstrated to have superior shielding characteristics for both galactic cosmic rays and solar particle events due to the high hydrogen content. A method to calculate the shielding effectiveness of a material relative to reference material from Bragg peak measurements performed using energetic heavy charged particles is described. Using accelerated alpha particles at the National Aeronautics and Space Administration Space Radiation Laboratory at Brookhaven National Laboratory, the method is applied to sample tiles from the Heat …


Sensitivity Analysis Method To Address User Disparities In The Analytic Hierarchy Process, Marie Ivanco, Gene Hou, Jennifer Michaeli Jan 2017

Sensitivity Analysis Method To Address User Disparities In The Analytic Hierarchy Process, Marie Ivanco, Gene Hou, Jennifer Michaeli

Mechanical & Aerospace Engineering Faculty Publications

Decision makers often face complex problems, which can seldom be addressed well without the use of structured analytical models. Mathematical models have been developed to streamline and facilitate decision making activities, and among these, the Analytic Hierarchy Process (AHP) constitutes one of the most utilized multi-criteria decision analysis methods. While AHP has been thoroughly researched and applied, the method still shows limitations in terms of addressing user profile disparities. A novel sensitivity analysis method based on local partial derivatives is presented here to address these limitations. This new methodology informs AHP users of which pairwise comparisons most impact the derived …


On A Time Domain Boundary Integral Equation Formulation For Acoustic Scattering By Rigid Bodies In Uniform Mean Flow, Fang Q. Hu, Michelle E. Pizzo, Douglas M. Nark Jan 2017

On A Time Domain Boundary Integral Equation Formulation For Acoustic Scattering By Rigid Bodies In Uniform Mean Flow, Fang Q. Hu, Michelle E. Pizzo, Douglas M. Nark

Mathematics & Statistics Faculty Publications

It has been well-known that under the assumption of a uniform mean flow, the acoustic wave propagation equation can be formulated as a boundary integral equation. However, the constant mean flow assumption, while convenient for formulating the integral equation, does not satisfy the solid wall boundary condition wherever the body surface is not aligned with the assumed uniform flow. A customary boundary condition for rigid surfaces is that the normal acoustic velocity be zero. In this paper, a careful study of the acoustic energy conservation equation is presented that shows such a boundary condition would in fact lead to source …