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Evaluation Of Test Specimen Geometry Of Asphalt Mixes Tested With The Asphalt Mixture Performance Tester, Abha Dwivedy Jan 2020

Evaluation Of Test Specimen Geometry Of Asphalt Mixes Tested With The Asphalt Mixture Performance Tester, Abha Dwivedy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Asphalt concrete, AC, is a heterogeneous material that is modeled as a homogeneous material. The disparity between material structure and theory presents issue with performance testing with test sample geometries, resulting in variability. The purpose of this research is to develop appropriate sample geometry for AMPT test for accurate characterization of asphalt mix and ease of testing.

Four sample geometries were fabricated for three mix types. All specimens are fabricated at 7%0.5% air voids and tested for AMPT tests. The effect of sample geometry was statistically analyzed using laboratory test results and performance predictions using FlexPAVE. For ranking analysis all …


Assessment Of Heat Stress For Outdoor Work Conditions In Saudi Arabia, Jamal Alanazi Jan 2020

Assessment Of Heat Stress For Outdoor Work Conditions In Saudi Arabia, Jamal Alanazi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Outdoor workers have an increased risk of heat stress in Saudi Arabia since it is one of the hottest places in the Middle East. Recently, the government decided to limit outdoor work hours during the months of June, July, and August every year, and banned working under the direct sunlight from 12:00 to 03:00 p.m., although outdoor workers in the petroleum, natural gas, or emergency maintenance work industries are exempt from this prohibition. Traditionally, the efforts by safety and health professionals to mitigate work-related heat injury has been directed toward the assessment of environmental heat stress (e.g., wet-bulb globe temperature), …


Exploring Aspects Of Science Literacy Demonstrated By Early Undergraduate Stem Majors Through A Manuscript-Style Writing Assignment, Samantha Lynn Jusino Jan 2020

Exploring Aspects Of Science Literacy Demonstrated By Early Undergraduate Stem Majors Through A Manuscript-Style Writing Assignment, Samantha Lynn Jusino

Graduate Theses, Dissertations, and Problem Reports (ETD)

Over the past twenty years, scientific literacy amongst undergraduates has not improved despite their exposure to higher education science classes. Underlying mechanisms of science literacy development are poorly understood; however, exposure to authentic practices in science has been demonstrated as a means to fostering science literacy development. A unique approach to studying science literacy is through examining the three domains of the science literacy conceptual framework developed in this study, Science as Access, Science as Process, and Science as a Sociopolitical Factor and their components as they emerge through the process of writing a manuscript-style writing assignment. In …


Modeling Of Rotary Packed Beds For Reactive And Non-Reactive Systems, Chinyere Evangeline Ezeobinwune Jan 2020

Modeling Of Rotary Packed Beds For Reactive And Non-Reactive Systems, Chinyere Evangeline Ezeobinwune

Graduate Theses, Dissertations, and Problem Reports (ETD)

Rotary packed beds (RPBs) are used in a wide range of reactive and non-reactive applications. In this research, a 2-d, first-principles, dynamic model of a non-reactive RPB that is used for heat exchange between the outgoing flue gas from a power plant and the incoming air to the boiler/pulverizer of the power plant is developed. A 2-d, first-principles model of a reactive RPB is developed where a functionalized metal-organic framework (MOF) is used for CO2 capture.

For the non-reactive system, a Ljungstrom-type air preheater (APH) is considered. Existing models for these rotating heat exchangers are typically 1-d. There are …


Gendered Access To Wetland Gardens (Dimba) In Northern Malawi, Rhoda Nyirenda Jan 2020

Gendered Access To Wetland Gardens (Dimba) In Northern Malawi, Rhoda Nyirenda

Graduate Theses, Dissertations, and Problem Reports (ETD)

Due to increasing degradation of upland fields and in the face of erratic rains and increasing occurrence of droughts and floods and increasing food prices, smallholder farmers in many places across sub Saharan Africa engage in wetland cultivation for livelihoods security (Mutambikwa et al., 2000). A cultivatable wetland area is considered prime land, and a desired opportunity that every rural family need for the purpose of food production. Studies have indicated that wetland cultivation significantly contributes to household’s income and food security. Wetland agriculture, however, in Malawi and most of the sub-Saharan African countries is marred with issues of access …


A Study Of Impact Protection Of Metacarpal Gloves, Faisal Mohammed Alessa Jan 2020

A Study Of Impact Protection Of Metacarpal Gloves, Faisal Mohammed Alessa

Graduate Theses, Dissertations, and Problem Reports (ETD)

Work-related wrist, hand, and finger injuries are highly prevalent in manufacturing and extractive industries. An analysis of mining-related hand injury data from over the past two decades (Alessa et al., 2020) showed that hand injuries caused by insufficient protection against impact loads (e.g. struck by accidents) were categorized with high severity. Existing literature lacks clear classification and quantification methods for the protection provided by impact-resistant gloves (i.e. metacarpal gloves). A new method to establish a quantitative measure of performance for commonly used metacarpal gloves was developed and evaluated.

In the first specific aim, an experimental study using cadaveric hand specimens …


Evaluating Inorganic Feed Phosphate Type And Further Potential Of Phytase Supplementation Using A Commercial Broiler Model, Angela Elsie Lamp Jan 2020

Evaluating Inorganic Feed Phosphate Type And Further Potential Of Phytase Supplementation Using A Commercial Broiler Model, Angela Elsie Lamp

Graduate Theses, Dissertations, and Problem Reports (ETD)

Optimizing feed formulation of poultry diets may be achieved by proper utilization of nutrients and feed additives. This will provide a less expensive and nutrient efficient diet to the bird. An experiment was conducted to evaluate early broiler performance, tibia mineralization, and mineral digestibility of broilers fed diets that differed in inorganic feed phosphates (IFP) but that were formulated to be either similar in dietary non-phytate phosphorus (nPP) and calcium to phosphorus ratio (Ca:P), total mineral content, or calculated prececal digestible phosphorus (CPDP). Dicalcium phosphate (DCP), monodicalcium phosphate (MDP), monocalcium phosphate (MCP), and defluorinated phosphate were used in formulations with …


Retrospective Evaluation Of The Changes In The Nasal And Pharyngeal Airway Volume After Miniscrew Assisted Rapid Palatal Expansion (Marpe) Appliance, Joanna Song Jan 2020

Retrospective Evaluation Of The Changes In The Nasal And Pharyngeal Airway Volume After Miniscrew Assisted Rapid Palatal Expansion (Marpe) Appliance, Joanna Song

Graduate Theses, Dissertations, and Problem Reports (ETD)

Background and Objectives: A transverse deficiency of the maxilla is a pervasive skeletal problem that can affect almost a quarter of the primary dentition population. The interesting relationship between rapid maxillary expansion (RME) and its effects on the surrounding airway is not well described in the literature. For today’s contemporary orthodontist, there are a variety of rapid palatal expanders (RPE) and expansion protocols to prescribe for patient treatment. Of late, the miniscrew-assisted RPE (MARPE) has been receiving attention by clinicians because of its increased orthopedic effects when compared to conventional RPE while avoiding the surgical procedure needed with SARPE. …


The Visual And Spectrophotometric Effect Of External Bleaching On Omnichroma Resin Composite And Natural Teeth, Michael Brian Evans Jan 2020

The Visual And Spectrophotometric Effect Of External Bleaching On Omnichroma Resin Composite And Natural Teeth, Michael Brian Evans

Graduate Theses, Dissertations, and Problem Reports (ETD)

Objective: To determine the visual and spectrophotometric effect external tooth bleaching has on natural tooth structure and OMNiCHROMA composite at various number of treatments. Variables were compared to determine if there is a detectable difference between the composite and the tooth before and after bleaching.

Methods: Preparation and restoration of 25 previously extracted teeth was completed. OMNiCHROMA composite was used. Each tooth was measured visually with a VITA shade guide and a colorimeter. Measurements were recorded before bleaching, after 5 and 10 treatments. Statistical analysis was completed and ΔE values between the composite and tooth were compared between the 3 …


Hepatitis B In At-Risk Groups: Three Studies To Guide Education, Testing, And Vaccination Efforts In West Virginia, Stacy Tressler Jan 2020

Hepatitis B In At-Risk Groups: Three Studies To Guide Education, Testing, And Vaccination Efforts In West Virginia, Stacy Tressler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Background and Objectives: For over a decade, West Virginia’s (WV) rate of acute hepatitis B has been the highest in the United States (US). In 2017, WV’s rate was 11.7 per 100,000 population, almost 12 times higher than the national rate. The increase in acute hepatitis B cases is largely due to substance misuse, including injection drug use (IDU). Hepatitis B is a vaccine preventable disease yet many at-risk adults remain unvaccinated and susceptible to infection. The objectives of our studies are to 1) describe yearly changes in acute hepatitis B incidence in WV and assess county-level impact of the …


Knowledge Of Content For Clinical Nursing Educators: An Ethnographic Investigation Of Clinical Experts Who Transition To The Role Of Novice Clinical Nursing Educator, Stacy Wheat Huber Jan 2020

Knowledge Of Content For Clinical Nursing Educators: An Ethnographic Investigation Of Clinical Experts Who Transition To The Role Of Novice Clinical Nursing Educator, Stacy Wheat Huber

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this research study was to identify and describe the teaching practices and the grounding experiences of the teaching practices novice educators use when teaching undergraduate students in the clinical patient care area. The following research questions guided this investigation: What teaching practices and teacher knowledge do novice clinical nursing educators demonstrate or draw from when teaching undergraduate nursing students in the clinical patient-care area? In what ways do novice clinical nursing educators change or adapt their teaching behaviors as a response to the context of the teaching/learning environment? What grounding educational or professional experiences do novice clinical …


On Body Mass Index Analysis From Human Visual Appearance, Min Jiang Jan 2020

On Body Mass Index Analysis From Human Visual Appearance, Min Jiang

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the past few decades, overweight and obesity are spreading widely like an epidemic. Generally, a person is considered overweight by body mass index (BMI). In addition to a body fat measurement, BMI is also a risk factor for many diseases, such as cardiovascular diseases, cancers and diabetes, etc. Therefore, BMI is important for personal health monitoring and medical research. Currently, BMI is measured in person with special devices. It is an urgent demand to explore conveniently preventive tools. This work investigates the feasibility of analyzing BMI from human visual appearances, including 2-dimensional (2D)/3-dimensional (3D) body and face data.

Motivated …


The Effects Of Household Substrates On The Evaporation Of Ignitable Liquids At Temperatures Up To 210℃, Caitlyn Wensel Jan 2020

The Effects Of Household Substrates On The Evaporation Of Ignitable Liquids At Temperatures Up To 210℃, Caitlyn Wensel

Graduate Theses, Dissertations, and Problem Reports (ETD)

In fire debris analysis, ignitable liquid residues are commonly identified using gas chromatography-mass spectrometry (GC-MS). The detection and identification of an ignitable liquid can help arson investigators determine whether a fire was intentional or accidental. To assist with the identification of ignitable liquid residues, chromatograms of questioned samples are typically compared to those of known ignitable liquids that have been weathered (evaporated) to different extents. Practitioners typically perform such weathering at room temperature and to a limited number of extents of weathering, so their database of weathered residues is likely to deviate markedly from casework residues. The ultimate goal of …


Effects Of Commission Errors During Noncontingent Reinforcement, Stephanie Hope Jones Jan 2020

Effects Of Commission Errors During Noncontingent Reinforcement, Stephanie Hope Jones

Graduate Theses, Dissertations, and Problem Reports (ETD)

Noncontingent reinforcement (NCR) is a behavioral treatment in which a reinforcer is provided at set intervals independently of responding. Although NCR is commonly used, effects of inconsistent implementation (i.e., implementation with integrity failures) during NCR were previously unknown. The current study included six participants, but full-integrity NCR suppressed problem behavior for only three participants. Thus, we evaluated effects of one kind of integrity failure, reinforcement of problem behavior, on NCR outcomes for three children who engaged in inappropriate vocalizations maintained by access to tangible items. Effects of commission errors were idiosyncratic across participants.


Time-Dependent Reliability Framework For Durability Design Of Frp Composites, Rajneesh Kumar Bharil Jan 2020

Time-Dependent Reliability Framework For Durability Design Of Frp Composites, Rajneesh Kumar Bharil

Graduate Theses, Dissertations, and Problem Reports (ETD)

The life-cycle performance, durability, and aging characteristics of Fiber Reinforced Polymer (FRP or Structural Composites) have been of keen interest to the engineers engaged in the FRP design, construction, and manufacturing. Unlike conventional construction materials such as steel and concrete, the design guidelines to account for the aging of FRP are somewhat scattered or not available in an approved or consistent format. Loss of strength over time or aging of any structural material should be of concern to engineers as the in-service lifespan of many engineering structures is expected to exceed 100 years. Use of durability strength-reduction factors or factors …


Understanding The Relationship Between Dental Fear, Behavior Management Problems, And Caregiver-Child Interactions During Young Child Dental Appointments, Christopher Kyle Owen Jan 2020

Understanding The Relationship Between Dental Fear, Behavior Management Problems, And Caregiver-Child Interactions During Young Child Dental Appointments, Christopher Kyle Owen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Positive oral health practices should begin early in life (AAPD; 2013; 2014; 2015); however, dental care-related fear and anxiety and behavior management problems are prevalent among young children in oral health (Klingberg & Broberg, 2007). The study explored caregiver and child dental care-related fear and anxiety, child behavior, and caregiver-child interactions during early childhood dental appointments. Caregiver-child dyad participants (N = 140) were collected from dental practices in West Virginia, Ohio, and Tennessee. Children (n = 139) in the sample were largely White (69.8%) and male (54.0%), with an average age of 3.05 years. Video-taped dental appointments for children under …


Three Essays On Energy Markets, Sultan Alturki Jan 2020

Three Essays On Energy Markets, Sultan Alturki

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation includes three essays investigating topics relevant to the energy markets. The first essay employs a new dataset to measure the impact of investor sentiment regarding oil prices on the U.S. inflation premium. The empirical analysis relies on Structural Vector Autoregression (SVAR) and out-of-sample forecasts. The results indicate that a one standard deviation positive shock to overall investor sentiment regarding oil prices results in a significant increase in the U.S. inflation premium by approximately 1.2% over the subsequent 10 weeks. Compared to individual investor sentiment, institutional investor sentiment regarding oil prices has a larger impact on the U.S. inflation …


The Exploration Of Nanotoxicological Copper And Interspecific Saccharomyces Hybrids, Matthew Joseph Winans Phd Jan 2020

The Exploration Of Nanotoxicological Copper And Interspecific Saccharomyces Hybrids, Matthew Joseph Winans Phd

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nanotechnology takes advantage of cellular biology’s natural nanoscale operations by interacting with biomolecules differently than soluble or bulk materials, often altering normal cellular processes such as metabolism or growth. To gain a better understanding of how copper nanoparticles hybridized on cellulose fibers called carboxymethyl cellulose (CMC) affected growth of Saccharomyces cerevisiae, the mechanisms of toxicity were explored. Multiple methodologies covering genetics, proteomics, metallomics, and metabolomics were used during this investigation. The work that lead to this dissertation discovered that these cellulosic copper nanoparticles had a unique toxicity compared to copper. Further investigation suggested a possible ionic or molecular mimicry …


Effects Of Appalachian Culture And Pregnancy Status On Pain-Related Fear, Cecelia Irene Nelson Jan 2020

Effects Of Appalachian Culture And Pregnancy Status On Pain-Related Fear, Cecelia Irene Nelson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fear of pain during pregnancy is an understudied phenomenon with important implications for prenatal and postpartum functioning. The aim of the current study was to understand the role of pregnancy and culture on pain-related fear in Appalachia. Archival datasets, and a new sample of women recruited via Amazon’s Mechanical Turk, were sources of data. Participants completed the Fear of Pain Questionnaire-9 and responded to demographic questions in order to ascertain whether they were pregnant at the time of the study as well as the number and nature of prior pregnancies. In support of hypotheses, results indicated that pregnant women reported …


Evolutionary Genomics Of Dynamic Sex Chromosomes In The Salicaceae, Ran Zhou Jan 2020

Evolutionary Genomics Of Dynamic Sex Chromosomes In The Salicaceae, Ran Zhou

Graduate Theses, Dissertations, and Problem Reports (ETD)

Identifying the sex-determination region (SDR) and other genomic features of sex chromosomes are of great importance in the studies of the evolution of sex. However, the process of accurately identifying the size and location of the SDR is often difficult, even when a genomic sequence is available. This usually is hindered by large repetitive elements and a lack of recombination in the SDR. In this thesis, I assemble sex chromosomes with whole genomic sequencing data, identify SDRs and explore their genomic features in two sister species from the Salicaceae family. I also develop an interpretation of the lability of the …


An Interactive Mobile Equipment Task-Training With Virtual Reality, Lazar Zujovic Jan 2020

An Interactive Mobile Equipment Task-Training With Virtual Reality, Lazar Zujovic

Graduate Theses, Dissertations, and Problem Reports (ETD)

Improving the quality of equipment training for the Heavy Equipment Operators (HEO) is a critical task in the ever-lasting effort to improve safety and eliminate equipment-related injuries in mining environments. Traditional miner training includes the use of hardcopy documents and video instructions. However, modern mobile and computer technology offers tremendous potential to improve the training process. One major responsibility for the heavy-machine operators is proper machine inspection. Establishing new training methods that utilize modern technologies—such as 360-degree images, videos, and Virtual Reality—and implementing computers for training purposes have a potential to help new operators learn how to conduct proper machine …


Mnemonic Discrimination And Social Anxiety: The Role Of State Anxiety, Gabriella T. Ponzini Jan 2020

Mnemonic Discrimination And Social Anxiety: The Role Of State Anxiety, Gabriella T. Ponzini

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Mnemonic Similarity Task (MST) measures mnemonic discrimination, or the ability to correctly identify new stimuli from highly similar, old stimuli. Neuroscientific and theoretical suppositions suggest that poor mnemonic discrimination may represent a potential risk or maintenance factor for anxious individuals. However, state affect appears to moderate the relation between mnemonic discrimination abilities and trait anxiety. The current study aimed to elucidate the nascent research on mnemonic discrimination and anxiety by evaluating the MST in a specific subtype of anxiety (i.e., social anxiety) and utilizing a clinically relevant stressor task (i.e., knowledge of a future speech). Participants (N = …


Role Of Ciliary Proteins Adp Ribosylation Factor Like Gtpase 13b (Arl13b) And Bardet-Biedl Syndrome-8 (Bbs8) In Photoreceptor Outer Segment Morphogenesis, Maintenance, And Viability, Tanya L. Dilan Jan 2020

Role Of Ciliary Proteins Adp Ribosylation Factor Like Gtpase 13b (Arl13b) And Bardet-Biedl Syndrome-8 (Bbs8) In Photoreceptor Outer Segment Morphogenesis, Maintenance, And Viability, Tanya L. Dilan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Photoreceptor neurons are modified primary cilia with an extended ciliary compartment known as the outer segment (OS). The mechanisms behind the elaboration of photoreceptor cilia, OS morphogenesis, and maintenance remain poorly understood. In this work, we focused on dissecting the role of two ciliary proteins, the small GTPase ADP-ribosylation factor-like GTPase 13B (ARL13B) and Bardet-Biedl Syndrome-8 (BBS8) in the context of photoreceptor biology. Both BBS8 and ARL13B are linked to defects in ciliogenesis (cilia development) and Retinitis Pigmentosa (vision loss). ARL13B is implicated in regulating ciliary length, and BBS8 is part of the Bardet-Biedl Syndrome complex (BBSome); the BBSome is …


Utilizing Conservation Genetics As A Strategy For Recovering The Endangered Candy Darter (Etheostoma Osburni) In West Virginia, Brin E. Kessinger Jan 2020

Utilizing Conservation Genetics As A Strategy For Recovering The Endangered Candy Darter (Etheostoma Osburni) In West Virginia, Brin E. Kessinger

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Candy Darter (Etheostoma osburni) is a small freshwater fish native to the New River drainage in West Virginia and Virginia that was listed as endangered in November 2018. It has been extirpated from much of its historic range in West Virginia, restricting it to the Gauley and Greenbrier river drainages. In addition to extirpations, the species is threatened by introgressive hybridization with the invasive Variegate Darter (E. variatum). Previous research primarily focused on hybridization, but population genetic analyses were limited. Population genetic analyses aim to identify distinct populations through genetic structure and characterize the levels …


Towards Large Eddy Simulation Of A Staged, Pressurized Oxy-Fuel Combustor, Alain Islas Montero Jan 2020

Towards Large Eddy Simulation Of A Staged, Pressurized Oxy-Fuel Combustor, Alain Islas Montero

Graduate Theses, Dissertations, and Problem Reports (ETD)

Identified by the DoE among the novel and transformational technologies, staged-pressurized oxy-fuel combustion (SPOC) is a promising low-cost, low-emission, and highly efficient tool for carbon capture utilization and storage (CCUS), with pulverized coal burning under elevated pressures and low recycled flue gas. A lab-scale SPOC facility, under establishment at Washington University in St. Louis (WUSTL), causes the critical need to develop accurate and reliable computational models to assist the ongoing WUSTL experiments. This constitutes the driving motivation of the present work. Specifically, comprehensive three-dimensional Large-eddy simulations (LES) of the lab-scale SPOC reactor, with most of important characteristics of a multi-phase …


Automated And Standardized Tools For Realistic, Generic Musculoskeletal Model Development, Trevor Rees Moon Jan 2020

Automated And Standardized Tools For Realistic, Generic Musculoskeletal Model Development, Trevor Rees Moon

Graduate Theses, Dissertations, and Problem Reports (ETD)

Human movement is an instinctive yet challenging task that involves complex interactions between the neuromusculoskeletal system and its interaction with the surrounding environment. One key obstacle in the understanding of human locomotion is the availability and validity of experimental data or computational models. Corresponding measurements describing the relationships of the nervous and musculoskeletal systems and their dynamics are highly variable. Likewise, computational models and musculoskeletal models in particular are vitally dependent on these measurements to define model behavior and mechanics. These measurements are often sparse and disparate due to unsystematic data collection containing variable methodologies and reporting conventions. To date, …


Comparative Study Of Model-Based And Learning-Based Disparity Map Fusion Methods, Douglas E. Kerr Jr. Jan 2020

Comparative Study Of Model-Based And Learning-Based Disparity Map Fusion Methods, Douglas E. Kerr Jr.

Graduate Theses, Dissertations, and Problem Reports (ETD)

Creating an accurate depth map has several, valuable applications including augmented/virtual reality, autonomous navigation, indoor/outdoor mapping, object segmentation, and aerial topography. Current hardware solutions for precise 3D scanning are relatively expensive. To combat hardware costs, software alternatives based on stereoscopic images have previously been proposed. However, software solutions are less accurate than hardware solutions, such as laser scanning, and are subject to a variety of irregularities. Notably, disparity maps generated from stereo images typically fall short in cases of occlusion, near object boundaries, and on repetitive texture regions or texture-less regions. Several post-processing methods are examined in an effort to …


It’S Just Muzak: Music, Activism, And Advertising., Avery Brzobohaty Jan 2020

It’S Just Muzak: Music, Activism, And Advertising., Avery Brzobohaty

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis builds on recent scholarship explaining the relationships between music, advertising, and society through a series of focused case studies in the clothing industry. Globally ubiquitous and reaching all socioeconomic strata, the fashion industry offers a useful focus because, in addition products, it also sells identity. Fashion is a means for individuals to create and express identity by associating themselves with certain brands and styles that help express social, political, economic, and ethical standings as well as gender, sexuality, race, and religion. This thesis considers the ways that sound and music influence the aesthetic and mood of recent fashion …


Development Of An Activity-Based Windowing Approach To Evaluate Real-World Nox Emissions From Modern Medium And Heavy-Duty Diesel Trucks, Rasik Pondicherry Jan 2020

Development Of An Activity-Based Windowing Approach To Evaluate Real-World Nox Emissions From Modern Medium And Heavy-Duty Diesel Trucks, Rasik Pondicherry

Graduate Theses, Dissertations, and Problem Reports (ETD)

The introduction of in-use emissions regulations by the United States Environmental Protection Agency (U.S.EPA) requires medium-duty (MD) and heavy-duty (HD) engine manufacturers to demonstrate emissions compliance during in-fleet operation. In the United States (U.S.), the Not-to-Exceed (NTE) method is used to evaluate real-world emissions compliance from on-highway MD and HD trucks. Regulatory agencies, engine manufacturers and research entities have identified that the NTE method incorporates numerous exclusions and evaluates emissions compliance only under selective operating conditions that are favorable for the selective catalytic reduction (SCR) system to reduce oxides of nitrogen (NOx) emissions efficiently. Such operation is typically encountered only …


Alternative Media And Mulches In Organic Vegetable Production, Heather R. Griffith Jan 2020

Alternative Media And Mulches In Organic Vegetable Production, Heather R. Griffith

Graduate Theses, Dissertations, and Problem Reports (ETD)

Reducing or eliminating waste from organic vegetable production can conserve money as well as resources. Conventional greenhouse production of vegetable transplants often relies on abundant fertigation which produces large amounts of polluted runoff, and the field production of organic vegetables frequently relies on the use of polyethylene mulch. A greenhouse study was conducted to determine if organic transplants can be successfully produced in a greenhouse under reduced soil moisture in order to reduce leaching of nutrients and potential water pollution. To test this, we compared the effect of reduced irrigation volumes to the standard practice of irrigating with 120% of …