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Disability Inclusion in Service Provision and Web Accessibility
No full textThis research examined the effect of human elements of service inclusion at a service encounter on the consumers? perception and behavioral intentions. The results from an experiential design model indicate that an inclusive service environment for persons with disabilities elicits positive perception, attitude, and behavioral intentions by consumers without disabilities. There was a significant interaction between hospitableness and expertise. In high hospitableness condition, consumers without disabilities who observed a service employee with an expertise showed the higher degree of gratitude and favorable word of mouth than those who didn?t observe the expertise of the service employee. Especially, it is notable that expertise (i.e., disability etiquette) plays a significant role in eliciting higher degrees of evaluation and willingness to reward
Influences of Seawater Flows on the Degradation of Organic Coatings Applied on Offshore Wind Turbines
Get PDFThe regular protection methods of offshore wind structures consist of the application of two or three layers of epoxy-based coatings with a polyurethane topcoat. The coating systems of offshore wind turbines are mostly tested on-site, where different coated samples are exposed to the sea water at the specific locations planned for the installations of the turbines. Despite several advantages of laboratory testing, the majority of laboratory-based tests have been limited to the exposure of coated or unprotected metals to stationary electrolytic solutions, while the flow-induced corrosion measurements have not received enough attention until recently. The focus of our work is to investigate the influence of applied mechanical stresses due to the water flow on the degradation of organic coatings. In order to resemble the condition of coated monopile structures in shallow water flow, an impingement chamber device and a wave tank were designed and constructed. The Electrochemical Impedance Stereoscopy (EIS) method was utilized for monitoring the electrochemical processes occurred during the degradation of coatings. Computational Fluid Dynamic (CFD) method, as well as Particle Image Velocimetry (PIV) tests were utilized in order to calculate the magnitude of applied stresses on the coating surfaces. Atomic Force Microscopy method (AFM) was employed for characterizations of coating? surfaces. The theory of thermo-activated processes in combination with the thermoelasticity equations were derived in a way to calculate the influence of applied stresses on different electrochemical parameters of the coatings? degradation. The afore-mentioned experimental methods and the developed analytical procedure can potentially predict the behavior of organic coatings applied on offshore wind turbines at different exposure zones with respect to the sea water flow
Contributing Factors of DUI Recidivism Among First-Time Offenders in North Dakota
Get PDFThis study explored utilizing tree-based machine learning models to identify associations in a range of 107 factors and DUI recidivism among first-time DUI offenders. Three tree-based machine learning models, Decision Tree, Random Forest, and Gradient Boosting were performed on 12,879 first-time DUI offenders during 2013-2017 using a three-year following period, to classify repeat DUI offenders. Study cohorts include 11,651 drivers without recidivism and 1,228 drivers with recidivism. The models tested 107 variables/predictors, including the driver?s demographic factors, drinking behaviors, traffic violations, crash histories, DUI-related violations, social-economic factors, and health and safety factors based on the driver?s residence. oversampling technique was used to balance two classes in the training data in all three models. The top 15-20 predictors were selected from the feature impact analyses of these predictions. Lastly, multiple logistic regression analyses were performed to quantify the effects of selected factors/predictors on the outcome. Among the three models, Gradient Boosting achieved the best predictions on both the original and oversampled datasets. Oversample techniques did improve prediction performances by roughly 10% on the F1 score for Gradient Boosting. Results coalesced around two findings. First, male drivers with higher BAC values, younger age at first DUI citation, whose first DUI citation took place during the weekday, had at least one low-risk citation within three years before first DUI citation, and lived in counties with lower income inequality ratio and higher violent crime rate were more likely to commit a subsequent DUI offense. Second, male drivers who complied with a BAC test upon arrest, whose first DUI citation took place on a weekday, had at least one low-risk citation within three years before the first DUI citation, lived in a county with a lower income inequality ratio, and higher violent crime rate were more likely to commit a subsequent DUI offense. Findings can be used by stakeholders in implementing and improving DUI prevention strategies. The study is limited to a single state, but the comparison of techniques and their shared findings suggest that a multitude and variety of approaches may be appropriate in future impaired driving prevention research
Three Essays on Renewable Jet Fuel Supply Chain Network Design and Traffic Safety
Get PDFBecause of rising energy consumption, climate change, and environmental concerns about fossil fuels, finding alternative renewable energy sources is becoming increasingly crucial. With the non-advanced share of the U.S. Renewable Fuel Standard having been mainly met by corn ethanol, many states are considering cellulosic or non-edible oilseed crops as the next source of biofuels. This study seeks to design a supply chain to produce renewable jet fuel (RJF) within the Midwest region and southeastern U.S. This is accomplished through the use of optimization models (mixed-integer linear programming). Furthermore, because RJF manufacturing incurs higher expenses than conventional jet fuel, the use of various monetary incentives is being studied to establish their usefulness in commercializing the supply chain. The findings of this study can be used by energy policymakers, RJF producers, and investors to operate in a competitive market while safeguarding the environment.
In another study, we evaluate speeding crash risk in North Dakota counties. In the United States, one of the most common contributing factors to car crashes is speeding. Speeding impairs a driver's ability to control and steer properly, as well as respond to a dangerous situation in a timely manner. Speeding crashes account for one-third of fatal crashes in the United States and are one of the risks for drivers on U.S. highways. Speeding crash risk can vary among regions. When it comes to allocating road safety expenditures to regions in order to reduce speeding crashes, it's vital for road management to understand which areas are at higher risk and should be prioritized for safety measures. This study uses a failure mode effect analysis method to evaluate the speeding crash risk
The Formation and Evolution of the Stockton Island Tombolo, Refined by OSL Geochronology
Get PDFPast research conducted on strandplain sequences has shown strandplains can record Holocene lake level changes. The Stockton Island tombolo, of the Apostle Islands National Lakeshore, holds such a record within its eastern and western strandplains; however, its data is at risk of being erased due to its position in a region of subsiding glacial isostatic adjustment. The objectives of this study were to provide geologic dates to evaluate the formation and evolution of the tombolo, as well as assess an apparent truncation of the western strandplain by the eastern. 19 samples were collected along transects from ridges within each strandplain. Samples were dated using Optically Stimulated Luminescence (OSL) techniques. These age results will provide useful geochronological context for future ecological and archaeological research on the tombolo; they will also provide a more robust understanding of past lake level variations which may enhance public education on water resources and climate change
An Evaluation Framework for Business Intelligence Visualization
Get PDFNowadays, data visualization is becoming an essential part of data analysis. Business Intelligence Visualization (BIV) is a powerful tool that helps modern business flows faster and smoother than ever before. However, studies on BIV evaluation are severely lacking; most evaluation studies for BIV is guided by general principles of usability, which have limited aspects covered for customers? needs. The purpose of this research is to develop a framework that evaluates BIV, including decision-making experience. First, we did a literature review for good understanding of research progress on related fields, and established a conceptual framework. Second, we performed a user study that implemented this framework with a set of questionnaires to demonstrate how our framework can be used in real business. Our result proved that this framework can catch differences among different designs of BIV from the users? standpoints. This can help design BIV and promote better decision-makings on business affairs
Analysis of SDR to Detect Long Range RFID Badge Cloners
Get PDFThis thesis proposes a way of detecting when radio frequency identification (RFID) badge credentials are being captured through the use of software defined radio (SDR). A method
for using SDR to detect when badge cloning technologies are in use on the premises is presented,
tested, and analyzed. This thesis presents an overview of the problem with badge systems and a
background literature review. Next, the proposed method of detection and its workings are
presented. Then, the strategy for evaluating the methods performance. This is discussed by
discussion and evaluation of the results. Finally, the thesis concludes with a discussion of the
method?s potential benefits and proposed future work
Understanding Water Quality, Vegetation Establishment, and Stakeholder Success for The Fargo Project: A Multi-Stakeholder Led Community-Based Green Infrastructure Project.
Get PDFThe Fargo Project is a dry detention basin that holds stormwater drained from urbanized and impervious areas that serves as a component of a greater stormwater infrastructure network. The project goals were to design a multi-use green infrastructure area that would invite neighboring residents into the basin. From its conception, the project has relied on partnerships between stakeholders. A survey was developed and deployed to all stakeholder groups that participated in the community-based project to access stakeholder success. The Fargo Project was viewed as a success by most stakeholders. Project partners felt that the basin?s main goal was to serve a functional purpose as well as contain natural habitat that provided a resource to the community. This new knowledge expands on the traditional top-down governmental approach and allows more input from stakeholders. One goal of The Fargo Project was to establish native vegetation in the bottom of the basin. A study was established using five different native seed mixes planted in four replicates in the spring of 2016. Four years after planting many of the native species used in the treatments, even though planted at high densities, failed to persist or were at levels below 4% cover. Flooding during the germination and establishment phase negatively affected the long-term persistence of planted native species. This study determined that native plantings within dry detention basins come with challenges atypical to restorations in other natural habitats.
Water quality at different vertical elevations within The Fargo Project basin was investigated. The vertical water quality was sampled after three large precipitation events at different stages within the basin: initial (first flush), at peak elevation, and outfall (as the basin drained). The water quality in two other dry detention basins were sampled for comparison. Most water quality analytes did not differ among the three detention basins except Total Suspended Solids which declined as the basin drained. The development of a passive vertical water quality sampling system using commonly available materials was effective at sampling vertical water quality in detention basins
BKCa-IP3R Decoupling in Hypertension
Get PDFHypertension is a significant risk factor for cardiovascular diseases and a leading cause of worldwide morbidity and mortality. Dysregulation of intracellular Ca2+ in vascular smooth muscle (VSM) cells is one major contributor to the development of vascular hypercontractility and remodeling in hypertension. Plasma membrane (PM)-localized large-conductance, Ca2+-activated K+ (BKCa) channels prevent hypercontractility through membrane hyperpolarization in response to vasoconstrictor-induced activation of inositol trisphosphate receptors (IP3Rs), localized on the sarcoplasmic reticulum (SR). However, loss of close contact or coupling between BKCa and IP3R may diminish the BKCa-mediated protection against hypercontractility and hypertrophy and contribute to the development of hypertension. The overall goal of this study was to understand the role of BKCa-IP3R coupling in the development of vascular hypercontractility and remodeling. I used a hypertensive animal model, spontaneously hypertensive rat (SHR), to study the impact of the loss of this coupling. My hypothesis was that there is a loss of communication between the IP3 receptors and the BKCa channels in SHR VSM cells leading to reduced BKCa current after IP3R activation.
My first objective was to determine the role of functional coupling of BKCa and IP3R in vascular hypercontractility and hypertrophy development. Based on the findings, one can conclude that in SHR mesenteric VSM cells, there is a loss of functional IP3R-BKCa coupling, and it might be involved in vascular hypercontractility and hypertrophy.
My second objective was to examine and compare the molecular coupling of BKCa and IP3R between normotensive and hypertensive rats. My data suggest that the molecular connection between BKCa and IP3R is disrupted in SHR VSM cells. My results also suggest that this loss of connection is not due to downregulation of junctophilin-2 (JPH2) but may be due to defective tethering of JPH2 to the PM.
Together, this research provides an improved understanding of the crucial roles played by BKCa-IP3R coupling in hypertension. An understanding of ion channel coupling under disease conditions may provide relevant caveats where BKCa channels are considered a therapeutic target. I expect that the knowledge gained from my studies will fundamentally advance the field of ion channel-based therapeutics, especially in cardiovascular disorders
Examining Thieno[3,4-b]pyrazine Through a Multifaceted Lens: From Extended Ring Functionalization to Ambipolar-Acceptor Copolymers
Get PDFA class of materials known as conjugated polymers (CPs) has been shown to integrate the physical properties of organic plastics such as low-weight, flexibility, and synthetic modularity with electronic semiconducting properties typically found in inorganic materials. While a variety of parameters determine the resultant material?s conductivity, a crucial factor is the bandgap (Eg). Specifically, thieno[3,4-b]pyrazine (TP) has found success in generating low Eg CPs (i.e. Eg < 1.5 eV), largely in part due to its ambipolar identity. Two strategies to achieve Eg values < 1 eV include extending the conjugation of TP through ring fusion and pairing TP with strong electron accepting moieties. The investigation into extended ring TPs as low bandgap homopolymers was initially pursued with the synthesis of poly(acenaphtho[1,2-b]thieno[3,4-e]pyrazine), a record setting low Eg homopolymer. Upon this realization of driving Eg? values down through ring fusion on the pyrazine portion of TP, additional analogues were considered with 2?4?2-dithieno[3,4-b:3?,4?-e]pyrazine as one of the most promising candidates due to its predicted Eg of 0.14 eV. Efforts into this research have produced a variety of precursors and analogues, adding to the family of TPs for further study.
A second strategy for Eg reduction is through the pairing of electronically mismatched units known as donors and acceptors. While this does reduce Eg, the underlying principles of the cause is disputed. Thus, to further understand the interactions in these types of copolymer systems, a small molecule study was designed with a strong donor, a strong acceptor, and the ambipolar unit TP in which six possible dimer configurations were synthesized and analyzed to determine the extent of donor-acceptor interactions. Lastly, an investigation into TP-acceptor alternating copolymers was carried out by pairing TP with two acceptors of varying accepting strength and contributions to polymer solubility. Because of the atypical design of these copolymers, a relatively new cross-coupling method known as direct arylation polymerization was used in their synthesis. The optimization of which produced a CP with an Eg of 0.93 eV. These results thus provide evidence for a new design motif for low bandgap CPs that further refines our understanding of donor-acceptor relationships