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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Evaluation of the Applicability of the Interactive Highway Safety Design Model to Safety Audit of Two-Lane Rural Highways

Chuo, Kaitlin 13 March 2008 (has links) (PDF)
The Interactive Highway Safety Design Model (IHSDM) is a suite of software developed by the Federal Highway Administration (FHWA) for monitoring and analyzing two-lane rural highways in the United States. As IHSDM is a fairly "young" program a limited amount of research has been conducted to evaluate its practicability and reliability. To determine if IHSDM can be adopted into the engineering decision making process in Utah, a study was conducted under the supervision of the Utah Department of Transportation (UDOT) to evaluate its applicability to audit safety of two-lane rural highways in Utah. IHSDM consists of six modules: Policy Review Module (PRM), Crash Prediction Module (CPM), Design Consistency Module (DCM), Traffic Analysis Module (TAM), Intersection Review Module (IRM), and Driver/Vehicle Module (DVM) (still under construction). Among the six modules, two were chosen for evaluation because of their applicability to audit safety of the two-lane rural highways in Utah, namely CPM and IRM. For the evaluation of the CPM, three two-lane rural highway sections were selected. The results of this evaluation show that the CPM can produce reasonably reliable crash predictions if appropriate input data, especially alignment data, reflect the existing conditions at reasonable accuracy and engineering judgment is used. Using crash records available from UDOT's crash database and CPM's crash prediction capability, UDOT's traffic and safety engineers can locate "hot spots" for detailed safety audit, thus making the safety audit task more focused and effective. Unlike the CPM, the outputs of the IRM are qualitative and include primarily suggestions and recommendations. They will help the traffic and safety engineers identify what to look for as they visit the sites, such as a lack of stopping sight distance and a lack of passing sight distance. The interpretation of the IRM requires knowledge of various aspects of highway design, familiarity with A Policy on Geometric Design of Highways and Streets by the American Association of State Highway and Transportation Officials (AASHTO), and experience in traffic engineering. Based on the findings of the study, it is concluded that the CPM and IRM of IHSDM could be a useful tool for engineering decision-making during safety audits of two-lane rural highways. But the outputs from these modules demand knowledge and experience in highway design. It is recommended that the other modules of IHSDM be tested to fully appreciate the capability of IHSDM. The software can be a knowledgebased program that can help novice engineers to learn how to design safe two-lane rural highways.
92

Predicting Equity Fund Returns: The Impact of the Momentum-Factor on Performance / Predicering av aktiefondsavkastning: Effekten av momentum-faktorn på prisutveckling

Hovberger, Pontus, Brunlid, Hugo January 2023 (has links)
Momentum has been a persistent and robust factor in explaining excess future returns, generating great interest from investors and financial analysts. Following the financial crisis of 2008 and the Covid-19 pandemic, there have been instances of significant momentum crashes. US Equity funds are used to gain insights about the properties of momentum and its predictive ability. Momentum performance is evaluated over the period 2000 to 2023. A multifactor model is developed, using factor attribution to explain the impact on fund performance over time by factors such as risk, size, value-growth orientation and momentum. Conclusions can be made that while momentum have previously been successful in predicting future returns, particularly for growth-oriented funds, recent market situations have lead to underperformance. The multifactor model, incorporating size and value-growth orientation, suggests that momentum is not entirely responsible for the poor performance following the Covid-19 crisis. / Momentum har historiskt sett varit en framgångsrik faktor för att predicera framtida avkastning, vilket har skapat stort intresse från investerare och finansiella analytiker. Efter finanskrisen 2008 och Covid-19 pandemin har det skett signifikanta momentumkrascher. Amerikanska aktiefonder används för att undersöka egenskaperna hos momentum och dess prediktiva förmåga. Prestationen av momentum utvärderas under tidsperioden 2000 till 2023. En multifaktormodell utvecklas, som använder faktor-attribution för att förklara hur fonders avkastning påverkas över tid av faktorer såsom risk, marknadsvärde, värde/tillväxt-orientering och momentum. En slutsats dras att även fast momentum har presterat väl historiskt för att predicera framtida avkastning, särskilt för tillväxt-orienterade aktiefonder, så har den senaste tidens marknadsrörelser lett till underprestation. Multifaktormodellen, som innehåller marknadsvärde och värde/tillväxt-orientering, indikerar att momentum inte är en lika stor anledning till underavkastningen efter Covid-19 krisen.
93

Les collisions routières chez les jeunes conducteurs les nuits de la fin de semaine : influence des facteurs humains et de l’environnement routier / Motor vehicle crashes among young drivers on the weekend nights : the influence of human and road environment factors

Tchomgang, Angeline January 2017 (has links)
INTRODUCTION : Les jeunes de moins de 25 ans constituent le groupe de conducteurs le plus impliqué dans les collisions routières (CR). L’objectif de cette étude est de déterminer l’importance de certains facteurs humains et de l’environnement routier dans les collisions les nuits de la fin de semaine chez les jeunes conducteurs. Les hypothèses postulent des chances plus élevées de CR les nuits de la fin de semaine, comparativement aux CR survenant à d’autres moments de la semaine, en présence d’un seul facteur de risque et de deux facteurs de risque. MÉTHODE : Cette étude transversale porte sur les CR ayant causé des blessures légères, graves ou mortelles au Québec chez les conducteurs âgés de 16 à 24 ans. Les informations sur les 58 478 CR survenus de 2007 à 2011 et les facteurs associés à ces CR proviennent de la banque de données de la Société de l’assurance automobile du Québec. Les CR les nuits de la fin de semaine (vendredi à samedi et samedi à dimanche de 20 h 00 à 04 h 59) sont comparées aux CR survenues aux autres moments de la semaine. L’importance des facteurs humains (p. ex., conduite avec capacités affaiblies) et de l’environnement routier (p. ex., courbes) dans ces CR est évaluée à l’aide d’analyses de régression logistique binaire et multinomiale. RÉSULTATS : Plusieurs facteurs sont liés à une augmentation des chances de CR les nuits de la fin de semaine, comparativement aux autres moments de la semaine. Ces facteurs incluent, par ordre d’importance décroissant : la conduite avec les capacités affaiblies (rapport des cotes ajusté [RCA] = 5,05 et intervalles de confiance à 99 % [IC 99 %] = 4,53‒5,64), la fatigue et le sommeil (RCA = 2,40 ; IC 99 % = 2,12‒2,73), la présence de passagers (RCA = 1,81 ; IC 99 % = 1,69‒1,94), le genre masculin (RCA = 1,36 ; IC 99 % = 1,27‒1,46), les courbes (RCA = 1,21 ; IC 99 % = 1,11‒1,32) et la vitesse (RCA = 1,18 ; IC 99 % = 1,09‒1,28). Les résultats sur la présence de deux de ces facteurs suggèrent l’importance des capacités affaiblies. Les chances de CR sont particulièrement importantes lorsque la présence de capacités affaiblies et d’un autre facteur est comparée à l’absence de ces deux facteurs. Dans ces cas, les chances de CR s’étalent de 5,33 (IC 99 % = 4,40‒6,45) pour la combinaison avec les courbes à 7,68 (IC 99 % = 6,52‒9,05) pour la combinaison avec la présence de passagers. CONCLUSION : Cette étude a permis de déterminer l’importance de plusieurs facteurs de risque, notamment la conduite avec capacités affaiblies, dans l’implication des jeunes conducteurs dans les CR les nuits de la fin de semaine. Les résultats suggèrent diverses stratégies afin de mieux cibler la conduite avec capacités affaiblies, incluant l’accès graduel à la conduite avec de jeunes passagers la nuit après l’obtention du permis de conduire. / Abstract : INTRODUCTION: Young people under 25 represent the group of drivers most involved in motor vehicle crashes (MVC). The aim of this study is to determine the significance of certain human and road environment factors in weekend night crashes involving young drivers. The hypotheses postulate higher odds of crash occurrence on weekend nights, as compared to crashes at other times during the week, when there is the presence of a single risk factor and two risk factors. METHOD: This cross-sectional study examines MVC causing minor, severe or fatal injuries in Quebec drivers aged 16 to 24. The information pertaining to the 58 478 MVC that occurred from 2007 to 2011 and the factors associated with these MVC comes from the databank of the Société de l’assurance automobile du Québec. Weekend night MVC (Friday to Saturday and Saturday to Sunday from 8:00 p.m. to 4:59 a.m.) are compared to MVC occurring at other times of the week. The significance of human factors (e.g., driving under the influence) and road environment factors (e.g., curves) in these crashes is assessed using binary and multinomial logistic regression analyses. FINDINGS: Several factors are associated with the increased odds of an MVC occurring on weekend nights, as compared to other times of the week. These factors include, by order of decreasing significance: driving under the influence (adjusted odds ratio [AOR] = 5.05 and 99% confidence interval [99% CI] = 4.53‒5.64), fatigue and sleep (AOR = 2.40; 99% CI = 2.12‒2.73), presence of passengers (AOR = 1.81; 99% CI = 1.69‒1.94), male gender (AOR = 1.36; 99% CI = 1.27‒1.46), curves (AOR = 1.21; 99% CI = 1.11‒1.32), and speed (AOR = 1.18; 99% CI = 1.09‒1.28). The findings on the presence of two of these factors suggest the significance of driving under the influence. The odds of MVC occurrence are particularly high when the presence of driving under the influence and another factor is compared against the absence of these two factors. In such instances, the odds of MVC occurrence range from 5.33 (99% CI = 4.40‒6.45) when curves are also involved to 7.68 (99% CI = 6.52‒9.05) when passengers are also present. CONCLUSION: This study determined the significance of several risk factors, particularly driving under the influence, in young drivers’ involvement in MVC on weekend nights. The findings suggest various strategies to better target driving under the influence, including gradual access to driving with young passengers at night after obtaining a driver’s licence.
94

The Development of an Improved Finite Element Muscle Model and the Investigation of the Pre-loading Effects of Active Muscle on the Femur During Frontal Crashes

Mendes, Sebastian B 31 August 2010 (has links)
"Mammalian skeletal muscle is a very complicated biological structure to model due to its non-homogeneous and non-linear material properties as well as its complex geometry. Finite element discrete one-dimensional Hill-based elements are largely used to simulate muscles in both passive and active states. There are, however, several shortfalls to utilizing one-dimensional elements, such as the impossibility to represent muscle physical mass and complex lines of action. Additionally, the use of one-dimensional elements restricts muscle insertion sites to a limited number of nodes causing unrealistic loading distributions in the bones. The behavior of various finite element muscle models was investigated and compared to manually calculated muscle behavior. An improved finite element muscle model consisting of shell elements and Hill-based contractile truss elements in series and parallel was ultimately developed. The muscles of the thigh were then modeled and integrated into an existing 50th percentile musculo-skeletal model of the knee-thigh-hip complex. Impact simulations representing full frontal car crashes were then conducted on the model and the pre-loading effects from active thigh muscles on the femur were investigated and compared to cadaver sled test data. It was found that the active muscles produced a pre-load femoral axial force that acted to slightly stabilize the rate of stress intensification on critical stress areas on the femur. Additionally, the active muscles served to direct the distribution of stress to more concentrated areas on the femoral neck. Furthermore, the pre-load femoral axial force suggests that a higher percentage of injuries to the knee-thigh-hip complex may be due to the effects of active muscles on the femur. "
95

Étude de l'association entre la sévérité des traumatismes crâniens et les inégalités sociales.

Houngnandan, Anselme Arthur B. 09 1900 (has links)
Introduction : La réduction des inégalités sociales de santé est un objectif de santé publique au Canada. Les liens entre les facteurs socio-économiques et les traumatismes en général ont été abondamment mesurés et illustrés notamment en pédiatrie, mais l’association entre les traumatismes crâniens et les inégalités sociales n’est pas assez investiguée dans la littérature. L’intérêt de ce travail en santé publique nous permettra de mieux connaitre les liens entre la défavorisation et les traumatismes crâniens particulièrement la sévérité. Objectif : L’objectif général de cette étude est d’examiner la relation entre les traumatismes crâniens et le statut socio-économique. Méthode : L’échantillon comprend 2269 patients ayant consulté le service d’urgence de l’Hôpital du Sacré Coeur de Montréal entre le 17 Mars 2008 et le 11 Janvier 2012, âgés de 14 ans et plus et habitant Montréal et Laval. Des analyses de régression logistiques ont été appliquées pour examiner la relation entre le quintile du statut socio-économique (mesuré à l’aide d’un proxy écologique) et la sévérité du traumatisme crânien (mesuré à l’aide de la tomodensitométrie). Résultat : A Montréal et à Laval, la cote d’avoir un scan normal est plus élevée chez les patients de quintile de revenu plus pauvre Q1 par rapport au quintile de revenu plus riche Q5, avec les valeurs respectives de 1,104 et 1,522 pour les régions de Montréal et Laval. A Laval lorsqu’on passe du quintile le plus pauvre Q1 au quintile le plus riche Q5, les cotes diminuent de 1,522 pour Q1; 1,302 pour le quintile de revenu bas; 1,126 pour le quintile de revenu moyen; 1,176 pour le quintile élevé à 1 pour le quintile le plus riche (quintile de référence). Conclusion : Bien que la relation entre les traumatismes et le statut socio-économique soit non significative, plusieurs questions se posent à travers ce mémoire notamment les causes différentes du traumatisme crânien en fonction du statut socio-économique et le territoire de résidence. D’autres recherches plus approfondies seraient utiles pour mieux informer les programmes de santé publique. Mots Clés : Traumatisme crânien, Statut socio-économique, Santé publique, Inégalités sociales, Chutes, Accidents de la route, Causes de traumatisme, Quintile de revenu / Introduction: Reducing social inequalities in health is a goal of health public in Canada. The links between socioeconomic factors and injuries in general have been extensively measured and illustrated, but the association between head trauma and social inequality is not enough investigated in the literature. The interest of this work in public health will enable us to better understand the links between deprivation and brain injuries. Objective: The overall objective of this study is to examine the relationship between brain injury and socioeconomic status Methods: The sample included 2269 patients who consulted the emergency department of the Hôpital du Sacré-Coeur de Montréal from March 17th 2008 to January 11th 2012, and aged 14 and over and living in Montreal and Laval. Logistic regression analyzes were used to examine the relationship between socioeconomic status (measured using a proxy ecological) and the severity of head injury (measured by computed tomography). Results: A Montreal and Laval, the odds of having a normal scan are higher in patients poorest income quintile compared to Q1 richest income quintile Q5, with the respective values of 1.104 and 1.522 for the Montreal and Laval. A Laval when moving from the poorest quintile Q1 to Q5 the richest quintile, the odds decrease by 1,522 for Q1; 1,302 for the bottom quintile of income 1,126 for the middle income quintile, 1.176 for quintile 1 for the richest (quintile reference). Conclusions: Although the relationship between head trauma and the socio-economic status is not significant, several questions arise through this memory of different causes including head trauma based on the socio-economic status and age, area of residence. Other further research would be useful to better inform public health programs. Keywords: Head trauma, Socioeconomic Status, Public Health, Social Inequality, falls, Crashes, Causes of trauma, income quintile
96

Vliv akreditace na kvalitu poskytované péče ve vybraných zdravotnických zařízeních. / The effekt of accreditation on the quality of health care providet in selected medical facilites.

SOMROVÁ, Jana January 2011 (has links)
The quality of nursing care is becoming an increasingly important concept in contemporary nursing. The most effective means of achieving quality of nursing care and the means of proof is the accreditation of medical facilities. It is a significant appreciation of professionalism, the work of health professionals and an important signal for the patients. Quality of care, security of supply and preventing potential risks for health care priority. The main aim of the thesis "The influence of accreditation on quality of care in selected health facilities" was to map the set of quality management and impact monitoring and evaluation of quality indicators in hospitals accredited by the Czech Republic. To determine whether accreditation has become an instrument to ensure comparable quality, and time has changed from an unpopular instrument into an instrument for continuous quality improvement. The survey took place from November 2010 to March 2011 in the form of quantitative data collection using an anonymous questionnaire survey in selected hospitals accredited by the Czech Republic. In the research study were asked managers of nursing care, main, upper station and sisters. The thesis has been established 6 goals. The first objective was to determine what indicators of quality nursing care in accredited hospitals pursue. Interested in us as quality indicators that were studied before accreditation, and quality indicators to setting up medical facilities in preparation for accreditation. The second objective was determine how frequently watched indicator of quality is monitored in hospital. The third objective was to determine whether there was in accredited hospitals to reduce adverse events - falls. The fourth objective was to determine whether there was in accredited hospitals to reduce the incidence of nosocomial infections in complying with barrier nursing regime. The fifth objective was to identify the biggest problems arose during the implementation of audits, completeness and comprehensiveness of nursing documentation management into practice. " The sixth objective was to determine whether there was during the preparation of an increase in hospital nursing staff. The thesis then was examined six hypotheses. First hypothesis Accredited hospitals monitor the quality of care provided by at least ten quality indicators - were confirmed. Hypothesis 2 The most frequently monitored indicator of the quality of nursing care, the prevalence of pressure ulcers - was confirmed. All respondents said they monitor the prevalence of pressure ulcers as an indicator of quality nursing care. Hypothesis 3 gaining accreditation to reduce the incidence of falls - was confirmed. Hypothesis 4 obtaining accreditation decreased nosocomial infections - was confirmed. Hypothesis 5 The biggest problem in implementing the audit, management complexity and completeness of nursing documentation in practice "has been an increase in paperwork for nursing staff - were confirmed. Hypothesis 6 During the preparation for accreditation has been an increase in nursing staff - has not been confirmed. Accreditation is perceived by respondents as beneficial for the hospital. Due to accreditation standards and developing quality indicators were identified risk areas in the provision of hospital care and detail can be paid to the prevention of adverse events, nosocomial infections and other risks. The results of work will be to provide medical facilities where the research was conducted investigation, the presentation of the research will be presented at a conference, the South Bohemian nursing days "and also gives the United Accreditation Commission of the Czech Republic as a presentation at the conference to be held early next year (spring ) 2012th Nursing standards were created.
97

Étude de l'association entre la sévérité des traumatismes crâniens et les inégalités sociales

Houngnandan, Anselme Arthur B. 09 1900 (has links)
No description available.
98

ENHANCING ACTIVE WORK ZONE SAFETY WITH INTRUSION ALERT TECHNOLOGIES: EMPIRICAL EVIDENCE ON EFFECTIVENESS AND IMPLICATIONS

Hrishikesh Suresh Pokharkar (14221811) 15 December 2022 (has links)
<p>  </p> <p>Highway workers are required to work close to moving traffic during road construction and maintenance activities, which exposes them to the risk of being struck by a distracted driver or intruding vehicle. In addition, work zones disturb the usual traffic flow and patterns due to changes in the existing geometric layout of a roadway, and this is also problematic for the drivers as they must navigate a layout of signs, barrels, and lane changes while keeping the vehicle in control. Moreover, late-night tasks, reckless driving, inconsistent work zones, drunk driving, and increased vehicle miles traveled are some of the additional causes of work zone incidents in the United States. Nationwide, around 40,000 accidents occur each year in highway work zones due to vehicle intrusion into the work zone and have steadily increased during the past ten years. Most often, the driver and passenger of the vehicle are the victims of such accidents. The resulting fatalities, injuries, and property damage due to such incidents lead to significant expenses, prolonged travel delays, and potential damage to expensive products in transit.</p> <p>While traditional safety precautions (e.g., truck-mounted attenuators, rumble strips, speed monitoring displays) can help enhance work zone safety, the number of work zone intrusions calls for designing and implementing emerging intrusion alert technologies to warn drivers and workers when errant vehicles intrude into the work zone. Several state Departments of Transportation (DOTs) have begun examining the use of intrusion alert technologies to mitigate work zone intrusions. While previous studies examined the general effectiveness (e.g., sound levels, work zone coverage, deployment characteristics, etc.) of these technologies in both controlled and active construction and maintenance work zones, there are still significant research gaps in investigating how well these intrusion technologies alert the driver and workers, and no documented best practices are available for transportation agencies and DOTs interested in implementing them. In addition, these technologies have been through many improvements and modifications, and further research is imperative to ascertain their chances of acceptance by workers and contractors.</p> <p>To address these gaps, this thesis focuses on (a) empirically examining the effectiveness, implications, and practices of four commercially available intrusion technologies in enhancing work zone safety through various field tests and surveys, and (b) empirically investigating the effectiveness of these technologies considering drivers’ cognitive processing (perception -reaction time) and responses in case of work zone intrusion. The findings of this research study provide detailed information on the identification and testing procedures of technologies and offer guidelines and recommendations for adopting these technologies for practitioners and professionals in the highway construction sector. The proposed decision-making matrix and multi-criteria decision-making framework are based on the empirical data obtained from the various field experiments, literature review, and evaluation survey. This study also provides valuable insights into the overall effectiveness (i.e., by considering functional characteristics, associated drivers’ responses and reactions, and current implementation) of commercially available intrusion technologies to incorporate required modifications in designing and implementing these technologies to enhance work zone safety. The long-term outcome of this study is to significantly reduce the injuries and fatalities in highway maintenance work zones in Indiana and across the country.</p>
99

Measurement of Meningeal Motion Using B-Mode Ultrasound as a Step Toward Understanding the Mechanism of Subdural Hematoma

Mallory, Ann Elizabeth 21 May 2014 (has links)
No description available.
100

DEVELOPMENT AND CALIBRATION OF A GLOBAL GEOMETRIC DESIGN CONSISTENCY MODEL FOR TWO-LANE RURAL HIGHWAYS, BASED ON THE USE OF CONTINUOUS OPERATING SPEED PROFILES

Camacho Torregrosa, Francisco Javier 31 March 2015 (has links)
Road safety is one of the most important problems in our society. It causes hundreds of fatalities every year worldwide. A road accident may be caused by several concurrent factors. The most common are human and infrastructure. Their interaction is important too, which has been studied in-depth for years. Therefore, there is a better knowledge about the driving task. In several cases, these advances are still not included in road guidelines. Some of these advances are centered on explaining the underlying cognitive processes of the driving task. Some others are related to the analysis of drivers’ response or a better estimation of road crashes. The concept of design consistency is related to all of them. Road design consistency is the way how road alignment fits drivers’ expectancies. Hence, drivers are surprised at inconsistent roads, presenting a higher crash risk potential. This PhD presents a new, operating speed-based global consistency model. It is based on the analysis of more than 150 two-lane rural homogeneous road segments of the Valencian Region (Spain). The final consistency parameter was selected as the combination of operational parameters that best estimated the number of crashes. Several innovative auxiliary tools were developed for this process. One example is a new tool for recreating the horizontal alignment of two-lane rural roads by means of an analytic-heuristic process. A new procedure for determining road homogeneous segments was also developed, as well as some expressions to accurately determine the most adequate design speed. The consistency model can be integrated into safety performance functions in order to estimate the amount of road crashes. Finally, all innovations are combined into a new road design methodology. This methodology aims to complement the existing guidelines, providing to road safety a continuum approach and giving the engineers tools to estimate how safe are their road designs. / Camacho Torregrosa, FJ. (2015). DEVELOPMENT AND CALIBRATION OF A GLOBAL GEOMETRIC DESIGN CONSISTENCY MODEL FOR TWO-LANE RURAL HIGHWAYS, BASED ON THE USE OF CONTINUOUS OPERATING SPEED PROFILES [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48543

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