Evaluating the Performance of Emergency Medical System in the US

Ebrahimi, Zhila Dehdari ProQuest Dissertations & Theses North Dakota State 2022 해외박사(DDOD)

New and exciting opportunities are emerging for operational researchers to create and use models that provide managers with solutions to enhance the quality of their services as the importance of the service sector grows in industrialized countries. The key to this process is the creation of time-dependent models that analyze complicated service systems and produce efficient staff schedules, allowing organizations to strike a balance between delivering high-quality services and avoiding unnecessary personnel costs. There is a need, particularly in the healthcare sector, to encourage effective management of an EMS, where the likelihood of survival is strongly correlated with the response time.Motivated by case studies investigating the operation of the Emergency Medical System (EMS), this dissertation aims to examine how operations research (OR) techniques can be developed to determine staff scheduling and maximize the ambulance to decrease service system delays. A capacity planning tool is developed that integrates a combination of queueing theory and optimization techniques to reduce the delay in the service system and maximize ambulance coverage.The research presented in this dissertation is novel in several ways. Primarily, the first section considers the Markovian models with sinusoidal arrival rates and state-dependency of service rate and uses a numerical method known as Stationary Independent Period by Period (SIPP) to determine the staff requirement of the service system. The final section considers the time dependency in locating an ambulance station across the network and allocating the ambulance to the patients to cover more 911 calls.

Multiscale Modeling of Conjugated Polymers Towards Predicting Their Multifunctional Behaviors

Alesadi, Amirhadi ProQuest Dissertations & Theses North Dakota State 2022 해외박사(DDOD)

Easy processability, tunable mechanical and optoelectronic properties, and the endless possibilities of molecular modifications enable conjugated polymers (CPs) to be used in a wide range of lightweight, low-cost, and flexible organic electronic devices. However, despite the tremendous efforts in molecular engineering and improved electronic properties, the thermomechanical-structure-property relationship of these semiconducting materials is still less investigated. Predicting the thermal, mechanical, and optoelectronic properties of CPs is challenging due to heterogeneous chain architectures and diverse chemical building blocks. To address this critical issue, this dissertation aims to employ novel multiscale modeling and data-driven approaches to characterize the thermomechanical and optoelectronic properties of CPs. In particular, we utilize machine learning (ML) and scale-bridging molecular modeling techniques scaled from quantum mechanics simulations to force field all atomistic molecular dynamics (AA-MD) and coarse-grained (CG)-MD simulations to explore the multifunctional behavior of CPs. Validated by experimental measurements, our AA-MD and CG-MD simulations can capture glass transition temperature (Tg), elastic modulus, and strain-induced deformation mechanism of the CPs with varied side-chain lengths and backbone moieties. Furthermore, through the integration of ML, AA-MD simulations, and experiments, we propose a simplified but accurate predictive framework to quantify Tg directly from the geometry of the CPs’ repeat unit. Next, first-principle calculations developed upon density functional theory (DFT) are utilized to quantify electronic configuration changes of CPs due to the charge injection. Finally, created upon ab initio excited state dynamics, we report a computational methodology to explore the photovoltaics (PV) performance of donor-acceptor organic bulk heterojunctions (BHJ). This computational framework facilitates screening of the best donor-acceptor molecules and narrows down the list of potential candidates to be used in BHJ. We believe data-driven and multiscale modeling approaches established in this dissertation are important milestones for the design and structure-property prediction of CPs and organic BHJ, paving the way for developing the next generation of organic electronics.

Limiting Financial Risk from Catastrophic Events in Project Management

Simonson, Peter Douglas ProQuest Dissertations & Theses North Dakota State 2020 해외박사(DDOD)

This dissertation develops a mixed integer linear program to establish the upper and lower bounds of the Alphorn of Uncertainty. For a project manager, planning for uncertainty is a staple of their jobs and education. But the uncertainty associated with a catastrophic event presents difficulties not easily controlled with traditional methods of risk management. This dissertation brings and modifies the concept of a project schedule as a bounded “Alphorn of Uncertainty” to the problem of how to reduce the risk of a catastrophic event wreaking havoc on a project and, by extension, the company participating in that project. The dissertation presents new mathematical models underpinning the methods proposed to reduce risk as well as simulations to demonstrate the accuracy of those models. The dissertation further assesses the complexity of the models and thus their practical application. Finally, the dissertation presents strategies to reduce the risk to a project of a catastrophic event using the upper bound of the Alphorn as the measure of risk.

Proposed Nonparametric Tests for the Umbrella Alternative in a Mixed Design for Both Known and Unknown Peak

Alsuhabi, Hassan Rashed ProQuest Dissertations & Theses North Dakota State 2019 해외박사(DDOD)

In several situations, and among various treatment effects, researchers might test for an umbrella alternative. The need for an umbrella alternative arises in the evaluation of the reaction to drug dosage. For instance, the reaction might increase as the level of drug dosage increases, where after exceeding the optimal dosage a downturn may occur. A test statistic used for the umbrella alternative was proposed by Mack and Wolfe (1981) using a completely randomized design. Moreover, an extension of the Mack-Wolfe test for the randomized complete block design was proposed by Kim and Kim (1992), where the blocking factor was introduced. This thesis proposes two nonparametric test statistics for mixed design data with k treatments when the peak is known and four statistics when the peak is unknown. The data are a mixture of a CRD and an RCBD.A Monte Carlo simulation is conducted to compare the power of the first two proposed tests when the peak is known, and each one of them has been compared to the tests that were proposed by Magel et al. (2010). Also, it is conducted to compare the power of the last four proposed tests when the peak is unknown. In this study, we consider the simulation from exponential, normal and t distributions with 3 degrees of freedom. For every distribution, equal sample sizes for the CRD portion are selected so that the sample size, n, is 6, 10, 16 and 20. The number of blocks for the RCBD are considered to be half, equal and twice the sample size for each treatment. Furthermore, a variety of location parameter configurations are considered for three, four and five populations. The powers were estimated for both cases, known and unknown peak.In both cases, the results of the simulation study show that the proposed tests, in which we use the method of standardized first, generally perform better than those with standardized second. This thesis also shows that adding the distance modification to the Mack-Wolfe and Kim- Kim statistics provides more power to the proposed test statistics more than those without the application of the distance modification.

Impact of Public Transit and Walkability on Quality of Life and Equity Analysis in Terms of Access to Non-work Amenities in the United States

Khan, Muhammad Asif ProQuest Dissertations & Theses North Dakota State 2020 해외박사(DDOD)

Seasonality of some Arctic Alaskan chironomids

Braegelman, Shane Dennis ProQuest Dissertations & Theses North Dakota State 2016 해외박사(DDOD)

Arthropods, especially dipteran insects in the family Chironomidae (midges) are a primary prey resource for many vertebrate species on Alaska's Arctic Coastal Plain. Midge-producing ponds on the ACP are experiencing climate warming that may alter insect seasonal availability. Chironomids display highly synchronous adult emergence, with most populations emerging from a given pond within a 3-5 day span and the bulk of the overall midge community emerging over a 3-4 week period. The podonomid midge Trichotanypus alaskensis Brundin is an abundant, univoltine, non-tubicolous species in tundra ponds near Barrow, Alaska, appearing early in the seasonal emergence sequence. To better understand regulation of chironomid emergence phenology, we (1) conducted a series of experiments on pre-emergence development of T. alaskensis at different temperatures, (2) monitored pre-emergent development of T. alaskensis larvae under field conditions. We also (3) compared community emergence records from ponds at Barrow, Alaska in the 1970s with similar data from 2009-2013 to look for shifts in emergence phenology. We found that (1) T. alaskensis has a consistent degree hours requirement to complete pupal development, (2) between pond thaw and pupation, T. alaskensis larval weight, body size, and head capsule size all increased, indicating that growth and development preceded pupation and emergence. Additionally, (3) we detected a significant advancement of overall midge emergence by about one week in Barrow tundra ponds. We conclude that the climate is warming and that (1) midge development is regulated by temperature, but (2) midge larvae require substantial feeding and growth during the post-thaw period, therefore (3) earlier emergence must be the result of warming and earlier food availability.

Evolution and development of a novel trait in Sepsidae

Melicher, Dacotah Michael ProQuest Dissertations & Theses North Dakota State 2016 해외박사(DDOD)

Evolutionary novelty, the appearance of new traits with no existing homology, is central to the adaptive radiation of new species. Novel traits inform our understanding of development and how developmental mechanisms can generate novelties. Sepsid flies (Diptera: Sepsidae) have a sexually dimorphic, jointed appendage used for courtship and mating. The appendage develops from the fourth abdominal histoblast nest rather than an imaginal disc. Histoblast nests in other species produce the adult epidermis and lack three-dimensional organization. The sepsid system is an opportunity to investigate the evolutionary history of a novel trait and the developmental mechanisms that pattern epidermal tissue into a complex structure. The appendage has a complex history of gain, loss, and recovery over evolutionary time. Appendage morphology is highly variable between species and does not correlate to body size. I collected larval epidermal tissue from 16 species across Sepsidae and one outgroup to trace the evolutionary history of gain, secondary loss, and recovery. I characterized histoblast nests in all segments and sexes, determining the nest size, number, and size of cells. The appendage-producing nest is sexually dimorphic in species after primary gain. Loss of the appendage shows a return to ancestral state while regain shows an increase in nest size in both sexes. The loss of sex dimorphism may indicate that mechanisms involved in specification may be active in females while genes involved in patterning are not activated during pupation. I assembled and annotated a reference transcriptome for the sepsid Themira biloba at using a custom bioinformatic pipeline that uses a merged assembly approach to maximize quality. This pipeline demonstrated an improvement over other methodologies using multiple published metrics for determining quality and completion. This pipeline also demonstrates how cloud computing architecture can complete bioinformatic tasks quickly and at low cost. I used the T. biloba transcriptome to identify differentially expressed genes involved in appendage patterning during pupation. I sequenced the appendage producing fourth male larval segment and the third male and fourth female segments. Many of the differentially expressed transcripts are involved in cell signaling, epidermal growth, and transcripts involved morphological development in other species.

Nonparametric Test for Nondecreasing Order Alternatives in Randomized Complete Block and Balanced Incomplete Block Mixed Design

Osafo, Mamfe ProQuest Dissertations & Theses North Dakota State 2020 해외박사(DDOD)

Nonparametric tests are used to test hypotheses when the data at hand violate one or more of the assumptions for parametric tests procedures. The test is an ordered alternative (nondecreasing) when there is prior information about the data. It assumes that the underlying distributions are of the same type and therefore differ in location. For example, in dose-response studies, animals are assigned to k groups corresponding to k doses of an experimental drug. The effect of the drug on the animals is likely to increase or decrease with increasing doses. In this case, the ordered alternative is appropriate for the study.In this paper, we propose eight new nonparametric tests useful for testing against nondecreasing order alternatives for a mixed design involving randomized complete block and balanced incomplete block design. These tests involve various modifications of the Jonckheere-Terpstra test (Jonckheere(1952), Terpstra(1954)) and Alvo and Cabilio’s test (1995). Three, four and five treatments were considered with different location parameters under different scenarios.For three and four treatments, 6,12, and 18 blocks were used for the simulation, while 10, 20, and 30 blocks were used for five treatments. Different tests performed best under different block combinations, but overall the standardized last for Alvo outperformed the other test when the number of treatments and number of missing observations per block increases.A simulation study was conducted comparing the powers of the various modification of Jonckheere-Terpstra (Jonckheere(1952), Terpstra(1954)) and Alvo and Cabilio’s (1995) tests under different scenarios. Recommendations are made.

Social Dialect Features of Military Speech: A Sociolinguistic Study of Fargo-Area Veterans

Albright, Anthony James ProQuest Dissertations & Theses North Dakota State 2020 해외박사(DDOD)

This mixed-methods study examines the potential existence of a military dialect separate from regional or social dialects experienced by civilians. In particular, how similar is the military-related storytelling lexicon of veterans in the Fargo-Moorhead area to the lexicon set forth in training bases and training manuals used by the U.S. military? The lexicon used by veterans in storytelling can sometimes seem opaque to an audience. It is typically dense with meaning borne by a few coded words. These words carry a contextual burden that can be better understood by an appeal to the dialect from which they were borne.In order to disentangle the veteran way of speaking from other overlapping and intersecting social and regional dialects that make up a subject’s typical speech, guided conversation and word-matching exercises were used to isolate lexicon that was typical to the military experience. The resulting interview transcripts were analyzed in comparison to military training manuals to arrive at a percentage of military-specific terms used in the guided conversation and a percentage of general knowledge military terms retained in the word-matching measure.The resulting 1.85% of military-specific terms and phrases used by participants in guided conversations and 61% retention of military-specific term knowledge was used to show that the military dialect not only exists but persists in the repertoire of veteran participants. As the majority of those who work with veterans are not veterans themselves, these percentages represent a significant barrier to understanding veteran storytelling. This barrier hinders the successful reintegration and mental health of veterans who return to their communities without knowing how to meaningfully express their stories in their existing support networks.

Combining Trait and Processing Perspectives of the Individual: Toward a New Assessment Model of Interpersonal Competence

Persich, Michelle Ruth ProQuest Dissertations & Theses North Dakota State 2020 해외박사(DDOD)

Satisfying interpersonal relationships are an important and beneficial part of life. However, despite that fact that most people desire close interpersonal relationships, some people are less successful at forming and maintaining these relationships than others. One plausible explanation for such individual differences is that people differ in their levels of interpersonal competence – their ability to consistently enact behaviors that are effective, socially appropriate, and satisfying to others. The present research sought to examine different approaches to understanding and assessing interpersonal competence. A comparison of these approaches led to the creation of an Integrated Interpersonal Competence Model (IICM) that sought to maximize the strengths of each individual approach.This new model was tested in two studies (total N = 348) with the goal of understanding why people receive higher (or lower) interpersonal competence (IC) scores and how competence is related to successful interpersonal functioning. Both Studies 1 and 2 examined how the individual components of the IICM contributed to one’s overall IC score. Both studies found that the ability to accurately process social information was related to one’s likelihood of receiving a high IC score. In addition, how an individual evaluated response options seemed to play the largest role in determining whether or not the person would enact the response. Finally, IC appeared to be composed of a blend of interpersonal warmth and dominance.Study 1 also examined the relationship between IC and daily life outcomes. Results showed that higher competence individuals tended to experience a greater frequency of positive events, higher levels of prosocial feelings and satisfaction, and enacted fewer hostile and submissive behaviors on a daily basis. Study 2 investigated how IC was perceived by others. Individuals who were higher in IC were perceived to have fewer antisocial feelings, and be less selfish by peers and parents, and had higher quality relationships with their parents. Interestingly, processing abilities were unrelated to daily and informant-reported outcomes, but personality-like tendencies toward enacting friendly and hostile behaviors were consequential. Overall, the integrated model produced insights into interpersonal competence and can provide a useful guide for future investigations of interpersonal competence.