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Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering

Society Dilemma Of Computer Technology Management In Today's World, Iwasan D. Kejawa Ed.D Apr 2022

Society Dilemma Of Computer Technology Management In Today's World, Iwasan D. Kejawa Ed.D

School of Computing: Faculty Publications

Abstract - Is it true that some of the inhabitants of the world’s today are still hesitant in using computers? Research has shown that today many people are still against the use of computers. Computer technology management can be said to be obliterated by security problems. Research shows that some people in society feel reluctant or afraid to use computers because of errors and exposure of their privacy and their sophistication, which sometimes are caused by computer hackers and malfunction of the computers. The dilemma of not utilizing computer technology at all or, to its utmost, by certain people in …


Challenges Of The Industrial Revolution Era 1.0 To 5.0 : University Digital Library In Indoensia, Merlin Apriliyanti, Ilham M Mar 2022

Challenges Of The Industrial Revolution Era 1.0 To 5.0 : University Digital Library In Indoensia, Merlin Apriliyanti, Ilham M

Library Philosophy and Practice (e-journal)

This study explains the development of the world of libraries to establish a very close relationship with the world of information technology. For this reason, facilities and infrastructure are needed to facilitate data and information retrieval quickly and accurately. Facing the challenges of the Industrial Revolution 5.0 era by utilizing information technology, libraries must also adapt to the times. Because the library has an important role, among others, as a source of information and the development of knowledge. Used libraries are still conventional to be converted into digital libraries. In essence, this development represents the desire of library users for …


Integration Management: A Bibliometric Study Of Research Trends, Shabir Hussain Khahro, Ayaz Babar, Fida Hussain Siddiqui, Tauha Hussain Ali, Ali Raza Khoso Jul 2021

Integration Management: A Bibliometric Study Of Research Trends, Shabir Hussain Khahro, Ayaz Babar, Fida Hussain Siddiqui, Tauha Hussain Ali, Ali Raza Khoso

Library Philosophy and Practice (e-journal)

Integration management has always been a topic of interest for researchers. It plays a significant role in the success of the projects. Integration management effectively incorporates all the aspects of projects and provides a roadmap towards their success. Based on the significance of the term, this paper assesses the research output of integration management since 1970 in different fields of the application using the Scopus database. The data was collected and analyzed through Microsoft Excel to analyze the research publications trend line, publication types and their access to the audience, organizations and countries involved, languages of publications, authors participating, and …


Modernization Of Scienttific Mathematics Formula In Technology, Iwasan D. Kejawa Ed.D, Prof. Iwasan D. Kejawa Ed.D Jul 2021

Modernization Of Scienttific Mathematics Formula In Technology, Iwasan D. Kejawa Ed.D, Prof. Iwasan D. Kejawa Ed.D

Department of Mathematics: Faculty Publications

Abstract
Is it true that we solve problem using techniques in form of formula? Mathematical formulas can be derived through thinking of a problem or situation. Research has shown that we can create formulas by applying theoretical, technical, and applied knowledge. The knowledge derives from brainstorming and actual experience can be represented by formulas. It is intended that this research article is geared by an audience of average knowledge level of solving mathematics and scientific intricacies. This work details an introductory level of simple, at times complex problems in a mathematical epidermis and computability and solvability in a Computer Science. …


Bibliometric Review Of Predictive Maintenance Using Vibration Analysis, Aashna Midha Ms., Ishita Maheshwari Ms., Kaushik Ojha Mr., Kritika Gupta Ms., Shripad V. Deshpande Mr. May 2021

Bibliometric Review Of Predictive Maintenance Using Vibration Analysis, Aashna Midha Ms., Ishita Maheshwari Ms., Kaushik Ojha Mr., Kritika Gupta Ms., Shripad V. Deshpande Mr.

Library Philosophy and Practice (e-journal)

Every day the world is depending more and more on machines in almost every aspect of life. With the increasing use of machines, there also needs to be an evolution in the maintenance of these machines. Predictive maintenance is a process used to monitor the equipment and machinery during its operation to detect any damages and/or deteriorations and enable the required maintenance plan in advance, resulting in reduced operational costs and full utilization of tools and parts. The fundamental goal of this bibliometric review paper is a comprehension of the extent and sources of the literature available for predictive maintenance …


Raw And Pure Education In The Society, Iwasan D. Kejawa Ed.D Jan 2021

Raw And Pure Education In The Society, Iwasan D. Kejawa Ed.D

Department of Educational Administration: Dissertations, Theses, and Student Research

What does education mean to individuals in the world today? Education is a way one can attain or improve his or her ability to lead and survive in the society of ours. Without educational training of the mind, it may be impossible to realize the importance of adaptability of living in the environment. Without education, It may also be difficult to embellish the use of both the mental and physical attributes possessed by individual beings.

What really is education? Education is the training of the mind to perform desire functions or to perpetuate the modality of obtaining an end or …


Solar Photovoltaic Performance Monitoring: A Bibliometric Review, Research Gaps And Opportunities, Javed Sayyad, Paresh Nasikkar Dec 2020

Solar Photovoltaic Performance Monitoring: A Bibliometric Review, Research Gaps And Opportunities, Javed Sayyad, Paresh Nasikkar

Library Philosophy and Practice (e-journal)

Electrical power generation has been revolutionized by growing demand and use of Renewable Energy (RE) sources such as Solar Photovoltaic (SPV) as the main electricity source in modern times. The main objective of this bibliometric analysis is to understand the scope of the literature available for SPV performance characterization. This detailed reviewed was performed on the documents related to SPV research considering all the subject categories from Scopus and Web of Science (WoS) databases. The patterns for the particular set of keywords were broke down with the recuperated outcomes from Scopus database in the language, publication type, year of publication, …


Scenario Analysis Of Downtown One-Way Street Conversions In Lincoln, Nebraska: A Case Study For Downtown Livability And Pedestrian Safety, Terrence Lage Dec 2020

Scenario Analysis Of Downtown One-Way Street Conversions In Lincoln, Nebraska: A Case Study For Downtown Livability And Pedestrian Safety, Terrence Lage

Community and Regional Planning Program: Theses and Student Projects

An era of downtown street design benefiting the automobile has become over designed for the movement of volumes of traffic in many North American cities. Since the 1950s, the primary focus of planners and traffic engineers has been to address the growing problem of traffic congestion caused by the suburban traveler coming into and out of downtown. The solution was retrofitting the original two-way street grid into a network of wide and straight multi-lane one-way corridors. This design successfully moved volumes of traffic through downtown streets but induced behavior to favor the automobile instead of design that favors active mobility …


Demystifying Artificial Intelligence Based Digital Twins In Manufacturing- A Bibliometric Analysis Of Trends And Techniques, Satish Kumar, Shruti Patil, Arunkumar Bongale, Ketan Kotecha, Anup Kumar M. Bongale, Pooja Kamat Nov 2020

Demystifying Artificial Intelligence Based Digital Twins In Manufacturing- A Bibliometric Analysis Of Trends And Techniques, Satish Kumar, Shruti Patil, Arunkumar Bongale, Ketan Kotecha, Anup Kumar M. Bongale, Pooja Kamat

Library Philosophy and Practice (e-journal)

Nowadays, data is considered as a new life force for operations of physical systems in various domains such as manufacturing, healthcare, transportations, etc. However, the hugely generated data, which mirrors the working essence of the product life cycle, is still underutilised. Digital Twin (DT), a collective representation of active and passive captured data, is a virtual counterpart of the physical resources that could help prevent effective preventive maintenance in any applied domain. Currently, lots of research is going on about the applicability of digital twin in smart IOT based manufacturing industry 4.0 environment. Still, it lacks a formal study, which …


The Effects Of Computer And Information Technology On Education, Iwasan D. Kejawa Ed.D Jun 2020

The Effects Of Computer And Information Technology On Education, Iwasan D. Kejawa Ed.D

School of Computing: Faculty Publications

In the society of ours, is it true really that computers and information technology have contributed immensely to the way we learn? After observing and reading various educational paraphernalia and scanning the environment research has shown that the educational systems have greatly been impacted by computers and information technology. With the growth of technology, the ways we learn have been improved tremendously. Innovative technologies have contributed to the innovation of learning in the education arena and outside. The traditional ways of conveying instructions to learners have been augmented with the use of computers information technologies. The educational system of our …


The Business Case For Industrial Safety: Revealing The Comprehensive Value Of Ergonomic Investments For Manufacturing Enterprises In Industry 4.0, Shane Stan Oct 2019

The Business Case For Industrial Safety: Revealing The Comprehensive Value Of Ergonomic Investments For Manufacturing Enterprises In Industry 4.0, Shane Stan

Honors Theses

How can today’s manufacturing enterprises construct, implement, and optimize modern safety initiatives in a manner that will present maximum return on investment and facilitate enterprise growth? Furthermore, how can these manufacturers assure individual ergonomic investments become part of a larger strategy to facilitate organizational change in safety? This work addresses these questions by placing industrial ergonomics in a business improvement context which comprehensively presents the financial returns and growth opportunities poised by modern safety initiatives. Additionally, to further strengthen the business case for industrial safety, an ergonomic action planning framework is established to guide the creation of holistic safety programs …


Mid To Late Season Weed Detection In Soybean Production Fields Using Unmanned Aerial Vehicle And Machine Learning, Arun Narenthiran Veeranampalayam Sivakumar Jul 2019

Mid To Late Season Weed Detection In Soybean Production Fields Using Unmanned Aerial Vehicle And Machine Learning, Arun Narenthiran Veeranampalayam Sivakumar

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Mid-late season weeds are those that escape the early season herbicide applications and those that emerge late in the season. They might not affect the crop yield, but if uncontrolled, will produce a large number of seeds causing problems in the subsequent years. In this study, high-resolution aerial imagery of mid-season weeds in soybean fields was captured using an unmanned aerial vehicle (UAV) and the performance of two different automated weed detection approaches – patch-based classification and object detection was studied for site-specific weed management. For the patch-based classification approach, several conventional machine learning models on Haralick texture features were …


Acuta Enews June 2009, Vol 38, No. 6 Aug 2018

Acuta Enews June 2009, Vol 38, No. 6

ACUTA Newsletters

In This Issue

From the President........Harvey "Buck" Buchanan, Florida State Univ., ACUTA President

Tech Talk: How Safe Do You Feet?................Kevin Tanzilto, Dux PR

"Financial Crisis Activity in Washington" Newsletter

ACUTA Web Seminar: Designing & Deploying 802.11n on a College Campus

Board Report...................... George Denbow, Univ. of Texas-Austin, ACUTA Secretary/Treasurer

DC Update Dave Ostrom, Washington State Univ. (retired)

lnfo Links ............. Randy Hayes, univ. of Northern lowa

Renewed Your Membership?

Web Page Lists Free Audio & Web Seminars from Vendors

ACUTA Corporate Liaison Committee Provides Website

Are You Linked ln? Do You Tweet?

The Value of Unified Communications .............Gary Audin, Delphi, …


Developing An Integrated Model For The Corn, Ethanol, And Beef Systems Using A Loosely Coupled Web Framework, Ryan Anderson Jun 2018

Developing An Integrated Model For The Corn, Ethanol, And Beef Systems Using A Loosely Coupled Web Framework, Ryan Anderson

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

With the global population approaching 9 billion people by the year 2050, the world’s food, energy, and water (FEW) resources must be used more intelligently to provide for everyone. While we understand how individual FEW systems behave using modeling, we cannot understand the full environmental and production impacts of decisions in each system without understanding how they are all linked together. An approach to coupling these systems is starting with identifying a few highly interconnected FEW systems. The corn, ethanol, and beef systems are large economic and agricultural drivers in the Midwest United States and are highly linked. Many individual …


Design Of A Distributed Real-Time E-Health Cyber Ecosystem With Collective Actions: Diagnosis, Dynamic Queueing, And Decision Making, Yanlin Zhou May 2018

Design Of A Distributed Real-Time E-Health Cyber Ecosystem With Collective Actions: Diagnosis, Dynamic Queueing, And Decision Making, Yanlin Zhou

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

In this thesis, we develop a framework for E-health Cyber Ecosystems, and look into different involved actors. The three interested parties in the ecosystem including patients, doctors, and healthcare providers are discussed in 3 different phases. In Phase 1, machine-learning based modeling and simulation analysis is performed to remotely predict a patient's risk level of having heart diseases in real time. In Phase 2, an online dynamic queueing model is devised to pair doctors with patients having high risk levels (diagnosed in Phase 1) to confirm the risk, and provide help. In Phase 3, a decision making paradigm is proposed …


Integration Of Hydrogeophysical Datasets And Empirical Orthogonal Functions For Improved Irrigation Water Management, Catherine E. Finkenbiner, Trenton E. Franz, Justin P. Gibson, Derek M. Heeren, J. D. Luck Jan 2018

Integration Of Hydrogeophysical Datasets And Empirical Orthogonal Functions For Improved Irrigation Water Management, Catherine E. Finkenbiner, Trenton E. Franz, Justin P. Gibson, Derek M. Heeren, J. D. Luck

Biological Systems Engineering: Papers and Publications

Precision agriculture offers the technologies to manage for infield variability and incorporate variability into irrigation management decisions. The major limitation of this technology often lies in the reconciliation of disparate data sources and the generation of irrigation prescription maps. Here the authors explore the utility of the cosmic-ray neutron probe (CRNP) which measures volumetric soil water content (SWC) in the top ~ 30 cm of the soil profile. The key advantages of CRNP is that the sensor is passive, non-invasive, mobile and soil temperature-invariant, making data collection more compatible with existing farm operations and extending the mapping period. The objectives …


The Rhetoric Of Science Education And Technology, Iwasan D. Kejawa Jan 2018

The Rhetoric Of Science Education And Technology, Iwasan D. Kejawa

School of Computing: Faculty Publications

Nearly thousands of science experiments are performed both on humans and animals every year in the United States (Gregory, 1999). Does Science enormously play a role in the well-beings of individual in the society? Research has found that science education is through motivation and satisfying the needs of humans. The scientific world is part of an elongated human development. This can be substantiated with the use and evolution of TECHNOLOGY and SCIENCE (Minton, 2004). Education of the entities that comprise the need to achieve the goal of TECHNOLOGY and SCIENCE which are important issues of today. Research has shown that …


Internet Of Underground Things In Precision Agriculture: Architecture And Technology Aspects, Mehmet C. Vuran, Abdul Salam, Rigoberto Wong, Suat Irmak Jan 2018

Internet Of Underground Things In Precision Agriculture: Architecture And Technology Aspects, Mehmet C. Vuran, Abdul Salam, Rigoberto Wong, Suat Irmak

School of Computing: Faculty Publications

The projected increases in World population and need for food have recently motivated adoption of information technology solutions in crop fields within precision agriculture approaches. Internet Of Underground Things (IOUT), which consists of sensors and communication devices, partly or completely buried underground for real-time soil sensing and monitoring, emerge from this need. This new paradigm facilitates seamless integration of underground sensors, machinery, and irrigation systems with the complex social network of growers, agronomists, crop consultants, and advisors. In this paper, state-of-the-art communication architectures are reviewed, and underlying sensing technology and communication mechanisms for IOUT are presented. Moreover, recent advances in …


Cyber-Physical System Characterization And Co-Regulation Of A Quadrotor Uas, Seth E. Doebbeling Aug 2017

Cyber-Physical System Characterization And Co-Regulation Of A Quadrotor Uas, Seth E. Doebbeling

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

An Unmanned Aircraft System (UAS) is a Cyber-Physical System (CPS) in which a host of real-time computational tasks contending for shared resources must be cooperatively managed to obtain mission objectives. Traditionally, control of the UAS is designed assuming a fixed, high sampling rate in order to maintain reliable performance and margins of stability. But emerging methods challenge this design by dynamically allocating resources to computational tasks, thereby affecting control and mission performance. To apply these emerging strategies, a characterization and understanding of the effects of timing on control and trajectory following performance is required. Going beyond traditional control evaluation techniques, …


Temporal Variations Of Water Productivity In Irrigated Corn: An Analysis Of Factors Influencing Yield And Water Use Across Central Nebraska, Tony Carr, Haishun Yang, Chittaranjan Ray Aug 2016

Temporal Variations Of Water Productivity In Irrigated Corn: An Analysis Of Factors Influencing Yield And Water Use Across Central Nebraska, Tony Carr, Haishun Yang, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

Water Productivity (WP) of a crop defines the relationship between the economic or physical yield of the crop and its water use. With this concept it is possible to identify disproportionate water use or water-limited yield gaps and thereby support improvements in agricultural water management. However, too often important qualitative and quantitative environmental factors are not part of aWP analysis and therefore neglect the aspect of maintaining a sustainable agricultural system. In this study, we examine both the physical and economic WP in perspective with temporally changing environmental conditions. The physical WP analysis was performed by comparing simulated maximum attainable …


Laboratory And Full Boom-Based Investigation Of Nozzle Setup And Restriction Effects On Flow, Pressure And Spray Pattern Distribution, Shane H. Forney Aug 2016

Laboratory And Full Boom-Based Investigation Of Nozzle Setup And Restriction Effects On Flow, Pressure And Spray Pattern Distribution, Shane H. Forney

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Pesticide application is an integral part of crop production and ground-based agricultural boom sprayers are used extensively to apply pesticides to the crop canopy or soil surface across millions of acres in the United States. Efficient application is necessary to minimize costs and limit adverse environmental impacts. Errors in flow rate and system pressure measurements may cause as-applied maps to incorrectly indicate application rates and could negatively affect downstream data processing or analysis. The goals of this study were to provide quantified measurements on the effects of nozzle setup errors on spray pattern uniformity and evaluate how laboratory patternator data …


A Five-Year Performance Review Of Field-Scale, Slow-Release Permanganate Candles With Recommendations For Second-Generation Improvements, Mark Christenson, Ann Kambhu, James Reece, Steve D. Comfort, Laurie Brunner Feb 2016

A Five-Year Performance Review Of Field-Scale, Slow-Release Permanganate Candles With Recommendations For Second-Generation Improvements, Mark Christenson, Ann Kambhu, James Reece, Steve D. Comfort, Laurie Brunner

Nebraska Water Center: Faculty Publications

In 2009, we identified a TCE plume at an abandoned landfill that was located in a low permeable siltyclay aquifer. To treat the TCE, we manufactured slow-release potassium permanganate cylinders (oxidant candles) that had diameters of either 5.1 or 7.6 cm and were 91.4 cm long. In 2010, we compared two methods of candle installation by inserting equal masses of the oxidant candles (7.6-cm vs 5.1-cm dia). The 5.1-cm dia candles were inserted with direct-push rods while the 7.6-cm candles were housed in screens and lowered into 10 permanent wells. Since installation, the 7.6-cm oxidant candles have been refurbished approximately …


Tractor Hydraulic Power Data Acquisition System, J. B.W. Roeber, Santosh Pitla, Michael F. Kocher, Joe D. Luck, Roger M. Hoy Jan 2016

Tractor Hydraulic Power Data Acquisition System, J. B.W. Roeber, Santosh Pitla, Michael F. Kocher, Joe D. Luck, Roger M. Hoy

Biological Systems Engineering: Papers and Publications

Tractor hydraulic power is used on a wide range of agricultural implements; however, the availability of operational hydraulic data at points other than full engine throttle position is limited. Operators could utilize this hydraulic data to maximize field efficiency and minimize machinery costs when determining suitable machinery for field operations. A field usable hydraulic test apparatus capable of measuring tractor hydraulic pressure and flow rate data was developed. The goal of this study was to determine if a hydraulic flow and pressure measurement device could be installed on the rear of a tractor to provide implement hydraulic power consumption at …


Fuel Consumption Models For Tractors With Partial Drawbar Loads, Bryan Jeffrey Smith Dec 2015

Fuel Consumption Models For Tractors With Partial Drawbar Loads, Bryan Jeffrey Smith

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Three models for predicting fuel consumption for agricultural tractors with partial drawbar loads were compared. Data were collected from eight John Deere tractors, JD 7230R (e23), 7250R (e23), 7270R (e23), 7290R (e23), 7290R (IVT), 8320R (16 speed), 8345RT (IVT), 8370R (IVT). The tractors were tested with 7 load levels per speed at four different travel speeds as close as possible to 4, 7.5, 10, and 13 km·h-1. The IVT tractors were operated in Auto mode and the geared tractors were shifted up three gears and throttled back to the same travel speeds as the IVT tractors. The 7 …


Lessons Learned From A Simulation Project In Construction Education, Saeed Rokooei, James D. Goedert Jun 2015

Lessons Learned From A Simulation Project In Construction Education, Saeed Rokooei, James D. Goedert

Department of Construction Engineering and Management: Faculty Publications

Virtual Interactive Construction Education (VICE) is a simulation designed for construction education. The purpose was to provide the traditional lecture-based construction contents along with supplementary instructions in a project-based learning environment. Six modules were proposed as a curriculum delivery guideline including: single span bridge, residential building, light commercial, heavy commercial, highway, and segmental bridge. The single span bridge was the first module used for prototype development providing an opportunity to design, analyze, implement, and test for effectiveness. This paper describes the design steps and results of this three-year research project. VICE-Bridge required participants to sequentially order the construction activities and …


Energy Harvesting And Storage: The Catalyst To The Power Constraint For Leveraging Internet Of Things (Iot) On Trains, Kelechi Nwogu May 2015

Energy Harvesting And Storage: The Catalyst To The Power Constraint For Leveraging Internet Of Things (Iot) On Trains, Kelechi Nwogu

Computer and Electronics Engineering: Dissertations, Theses, and Student Research

The success of Wireless Sensor Networks is heavily constrained by its reliance on storage technology like batteries, which are a finite resource. Whilst the number of transistors in an IC doubles every 18 months, the energy density of batteries is relatively flat during the same time period. This is a key challenge in leveraging the Internet of Things on trains.

The gravity of this problem is increased by an order of magnitude when the network is to be scaled up to hundreds or thousands of nodes. Comprehensive research and development efforts have been devoted to building ultra-low power sensors. These …


Eight Principles Of Uncertainty For Life Cycle Assessment Of Biofuel Systems, Adam J. Liska Jan 2015

Eight Principles Of Uncertainty For Life Cycle Assessment Of Biofuel Systems, Adam J. Liska

Adam Liska Papers

New environmental regulations in the USA and Europe require a reduction of greenhouse gas (GHG) emissions from transportation fuels as a component of climate change mitigation policy. The US Energy Independence and Security Act of 2007 (EISA) requires GHG emission reductions from the life cycles of biofuels compared to gasoline, by 20% for ethanol from maize grain (maize-ethanol), 60% for cellulosic ethanol, and 50% for other advanced biofuels. To determine these reductions, the US Environmental Protection Agency (EPA) employs life cycle assessment (LCA) methods which were not used previously in national environmental regulations. These regulations, entitled the “Renewable Fuel Standard …


Chemical Storage Of Wind Energy By Renewable Methanol Production: Feasibility Analysis Using A Multi-Criteria Decision Matrix, Michael J. Matzen, Mahdi H. Alhajji, Yaşar Demirel Jan 2015

Chemical Storage Of Wind Energy By Renewable Methanol Production: Feasibility Analysis Using A Multi-Criteria Decision Matrix, Michael J. Matzen, Mahdi H. Alhajji, Yaşar Demirel

Department of Chemical and Biomolecular Engineering: Faculty Publications

This study is for the technoeconomic analysis of an integral facility consisting of wind energy-based electrolytic hydrogen production, bioethanol-based carbon dioxide capture and compression, and direct methanol synthesis. ASPEN Plus was used to simulate the facility producing 97.01 mt (metric tons) methanol/day using 138.37 mt CO2/day and 18.56 mt H2/day. A discounted cash flow diagram for the integral facility is used for the economic analysis at various hydrogen production costs and methanol selling prices. The feasibility analysis is based on a multi-criteria decision matrix consisting of economic and sustainability indicators comparing renewable and non-renewable methanol productions. …


Ventilation Rates And Airflow Pathways In Patient Rooms: A Case Study Of Bioaerosol Containment And Removal, Ehsan S. Mousavi, Kevin R. Grosskopf Jan 2015

Ventilation Rates And Airflow Pathways In Patient Rooms: A Case Study Of Bioaerosol Containment And Removal, Ehsan S. Mousavi, Kevin R. Grosskopf

Durham School of Architectural Engineering and Construction: Faculty Publications

Most studies on the transmission of infectious airborne disease have focused on patient room air changes per hour (ACH) and how ACH provides pathogen dilution and removal. The logical but mostly unproven premise is that greater air change rates reduce the concentration of infectious particles and thus, the probability of airborne disease transmission. Recently, a growing body of research suggests pathways between pathogenic source (patient) and control (exhaust) may be the dominant environmental factor. While increases in airborne disease transmission have been associated with ventilation rates below 2 ACH, comparatively less data are available to quantify the benefits of higher …


Influence Of Spatial Variations Of Railroad Track Stiffness And Material Inclusions On Fatigue Life, Celestin Nkundineza Jan 2015

Influence Of Spatial Variations Of Railroad Track Stiffness And Material Inclusions On Fatigue Life, Celestin Nkundineza

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Railroad transportation is very important for economic growth and effective maintenance is one critical factor for its economic sustainability. The high repetitive forces from a moving railcar induce cyclic stresses that lead to rail bending and potential deterioration due to fatigue crack initiation and propagation. Previous research for prediction of fatigue life has been done under the assumptions of a uniform track bed and a homogeneous rail. However the spatial variation of the track stiffness is expected to increase the maximum stresses in the rail and, therefore, accelerate the fatigue process. The research described in this dissertation is focused on …