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Highway Effects on Small Mammal Communities and Effectiveness of a Deer-Vehicle Collision Mitigation StrategyRosa, Silvia A. S. 01 May 2006 (has links)
My work focused on the study of road effects and mitigation of negative impacts of roads on wildlife. Two different studies were conducted on Interstate 15, in southern Utah. My first study reported on road effects on small mammal communities. The results suggested that overall, there was no clear effect on small mammal populations relative to distance from the road. Most small mammal species did not appear to be negatively affected by the presence of the road. Instead, the road seemed to have either a neutral or a positive effect. The abundance and diversity of small mammals responded more markedly to microhabitat than to the presence of the highway. I suggest that other factors such as water runoff during rainy periods may be responsible for the detected patterns by increasing primary productivity in areas close to the road. I conclude that roads may often provide favorable micro-habitat in the desert landscape for many small mammals and that the disturbance caused by the highway use (e.g., noise, road surface vibration) seemed to have a negligible effect on these organisms . My second study examined the effectiveness of a mitigation strategy to reduce mule deer (Odocoileus hemionus) road mortality. Mitigation included exclusion fencing, earthen escape ramps, and underpass crossing structures . Results comparing mortality data before and after the mitigation showed 76-96% reductions of deer vehicle collisions. There was no evidence that the mitigation caused "end-of-the-fence" problems, i.e., higher mortality at the ends of the exclusion fencing . Results from underpass camera monitoring showed an increasing deer use of the underpasses over time. The volume of crossings recorded on new underpass structures approached the volume of crossings observed in a 20-year-old control underpass. My results suggest that human use and location of structures influenced deer use of underpasses. Overall results show that the mitigation strategy was effective and has reduced the number of deer-vehicle accidents while allowing easier wildlife movement across the landscape. I presented future maintenance recommendations to assure a long-term success for this strategy.
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Alarming Rate of Substance Use in Motor Vehicle Collisions at an Appalachian Trauma CenterProctor, Rebecca, Taylor, Melissa P., Quinn, Megan, Burns, Bracken 03 December 2020 (has links)
Prescription drug use is a growing public health concern and studies show it is a contributing risk to motor vehicle collisions. The Appalachian region is also known to have an ever-increasing number of patients on controlled substances. This retrospective study of patients from the years 2011-2015 on controlled substances presenting to an Appalachian Level 1 trauma center after a motor vehicle or motorcycle collision was analyzed in order to determine the rate of opioid use among victims of motor vehicle collisions in the system, as well as evaluate for any differences in resource utilization between these patients and patients not using controlled substances. A total of 2,570 patients were included in the study. Seven-hundred sixty-eight (29.9%) individuals were found to be on a controlled substance. There was a similar mortality rate in both groups (2.8% vs 3.6%). There was no significant difference in hospital length of stay (LOS), intensive care unit (ICU) LOS, ventilator days, or injury severity score. Statistically significant findings include the type of crash (motor vehicle crash vs motorcycle crash) (p=0.003) and position in the vehicle (driver vs passenger) (p<0.001). Motor vehicle crashes and driver position were significantly associated with the presence of a controlled substance.
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Predictors of Driving Exposure in Bioptic Drivers and Implications for Motor Vehicle Collision RatesZhou, Alicia Marie Powers 09 August 2016 (has links)
No description available.
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アルミニウム合金製防護柵の実車衝突に関する数値解析的研究伊藤, 義人, Itoh, Yoshito, 宇佐見, 康一, Usami, Koichi, 貝沼, 重信, Kainuma, Shigenobu, 杉江, 昌宣, Sugie, Masanobu 03 1900 (has links)
No description available.
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Αναγνώριση κινδύνου σύγκρουσης αυτοκινήτου με προπορευόμενο με ψηφιακή επεξεργασία σημάτων videoΕυαγγελίου, Κωνσταντίνος 21 October 2011 (has links)
Η αποφυγή συγκρούσεων με αναγνώριση της θέσης και της σχετικής ταχύτητας προπορευόμενων οχημάτων είναι μια άκρως ενδιαφέρουσα εφαρμογή που βρίσκεται σε πειραματικό στάδιο. Η ύπαρξη πολλαπλών αντικειμένων στο οπτικό πεδίο της κάμερας δημιουργεί προβλήματα στον ακριβή εντοπισμό του προπορευόμενου οχήματος, ενώ η έλλειψη βάσεων δεδομένων με κατηγοριοποιημένα παραδείγματα είναι ένα επιπλέον εμπόδιο για την ανάπτυξη της εφαρμογής αυτής.
Στην εργασία αυτή περιγράφονται οι υπάρχουσες εφαρμογές όσον αφορά στο πρόβλημα της μηχανικής όρασης στην αυτοκίνηση, τα προβλήματα που λύνουν αλλά και οι δυσκολίες που συνεχίζουν να υπάρχουν.
Αναφέρονται οι αιτίες της έλλειψης βάσεων δεδομένων με κατηγοριοποιημένα παραδείγματα και αναλύεται η ημιαυτόματη μέθοδος (Random Walker) στην οποία καταφεύγουμε για τον λόγο αυτό.
Εν συνεχεία θα παρουσιαστούν τα αποτελέσματα της ανάπτυξης σε Matlab που πραγματοποιήθηκε, τα συμπεράσματα που προέκυψαν, αλλά και οι μελλοντικές προκλήσεις. / In this diplom work, the ways followed to deal with the issue of mechanical vision in car driving are described. The reasons why there there are not any specific data sets are decribed and the focus of this work is on the Random Walker algorithm.
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Padrões espacial e temporal do atropelamento de mamíferos em uma rodovia no cerrado brasileiroOliveira, Adriana Nepomuceno de 24 March 2011 (has links)
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Previous issue date: 2011-03-24 / Financiadora de Estudos e Projetos / This thesis is divided into a general introduction on the issue of roads ecology and the main factors that lead to the general public and the animals roadkills, followed by a chapter that investigates if there is spatial and seasonal patterns of medium and big mammals roadkills in a road (SP-225) in northeast of São Paulo State, Brazil. The road is located in a region of Cerrado, semideciduous forest and riparian vegetation. Data were collected during the years 2006, 2007 until February 2008. 114 roadkills were recorded for medium and large mammals.-vehicle collision were recorded,. The two species most hit were Cerdocyon thous and Lepus europaeus, with 32 and 22 records respectively .It was analyzed if there was spatial clustering of roadkills per kilometer between Km 75-235 and noticed the Km 146- is the one that has the highest number of roadkills, with 7 records, followed by Km 115 and Km 125, with 5 and 4 records respectively. When road is divided into sections of 5 km each, the passages that had higher indices of collision were Km 145-150, followed by passage of Km 125-130, with 15 and 10 roadkills respectively. This analysis showed that the most impacted areas have been the most probable for roadkills. In these sections, it is indicate the application of mitigation measures. The temporal patterns of roadkills distribution were not clear, except in 2006, when the rainy season showed a higher rate of roadkills than dry season. Using three species as a model, it was analyzed the relationship between the landscape around the Road and roadkills frequency. Three species were chosen, the two most frequently hit (Cerdocyon thous and Lepus europaeus) and one threatened (Chrysocyon brachyurus). The roadkills of C. thous were associated to areas of reforestation and less urban, while the roadkills of L. europaeus were in areas of planting (reforestation and orange s crop). The urban areas and with less pasture were associated to the C. brachyurus roadkills. / Esta dissertação está dividida em uma introdução geral sobre uma das questões da área de Ecologia de Estradas mais impactantes para o público em geral: o atropelamento de fauna silvestre em rodovias, e posteriormente em um capítulo que visa investigar se há e quais são os padrões espaciais e temporais dos atropelamentos de mamíferos de médio e grande porte na rodovia SP-225, na região nordeste do Estado de São Paulo, Brasil. A SP-225 está localizada em uma região de Cerrado, Floresta Semidecidual e Mata Ripária. Os dados foram coletados de Janeiro de 2006 a Fevereiro de 2008, antes da duplicação da rodovia. Foram registrados 114 atropelamentos de mamíferos de médio e grande porte nesta rodovia. As duas espécies mais atropeladas foram o Cerdocyon thous e a Lepus europaeus, com 32 e 22 registros cada uma. Foi analisado se existiam agregações espaciais dos atropelamentos em cada quilometro da rodovia entre os Km 75 e 235, sendo registrado um alto número de atropelamentos de mamíferos no Km 146, com 7 ocorrências, seguidos pelo Km 115 e pelo Km 125, com 5 e 4 ocorrências respectivamente. Quando a estrada foi divida em trechos de cinco quilômetros, os locais que apresentaram os maiores índices de acidentes foram o trecho Km 145-150, seguido pelo trecho Km 125-130, com 15 e 10 registros respectivamente. Nestes trechos, indica-se a aplicação de medidas mitigadoras. O padrão temporal de distribuição dos atropelamentos não foi clara, exceto no ano de 2006, quando a estação chuvosa apresentou um índice maior de atropelamentos do que a estação seca. Usando três espécies como modelo, analisou-se a relação entre a paisagem ao redor da estrada e a frequência de atropelamentos. Foram escolhidas as duas espécies mais atropeladas (Cerdocyon thous e Lepus europaeus) e uma considerada vulnerável à extinção (Chrysocyon brachyurus). Os atropelamentos de C. thous foram associados a áreas de reflorestamento e áreas menos urbanas, enquanto que os de L. europaeus foram a áreas de plantação (reflorestamento e laranjal) e a áreas com menos vegetação nativa. As áreas urbanas e com menos pastos foram aquelas associadas às ocorrências de atropelamento de C. brachyurus.
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Biomechanical Responses of Human Surrogates under Various Frontal Loading Conditions with an Emphasis on Thoracic Response and Injury ToleranceAlbert, Devon Lee 04 June 2018 (has links)
Frontal motor vehicle collisions (MVCs) resulted in 10,813 fatalities and 937,000 injuries in 2014, which is more than any other type of MVC. In order to mitigate the injuries and fatalities resulting from MVCs, new safety restraint technologies and more biofidelic anthropomorphic test devices (ATDs) have been developed. However, the biofidelity of these new ATDs must be evaluated, and the mechanisms of injury must be understood in order to accurately predict injury. Evaluating the biomechanical response, injury mechanisms, and injury threshold of the thorax are particularly important because the thorax is one of the most frequently injured body regions in MVCs. Furthermore, sustaining a severe thoracic injury in an MVC significantly increases mortality risk.
The overall objective of this dissertation was to evaluate the biomechanical responses of human surrogates under various frontal loading conditions. This objective was divided into three sub-objectives: 1) to evaluate the biofidelity of the current frontal impact ATDs, 2) to evaluate the effect of different safety restraints on occupant responses, and 3) to evaluate rib material properties with respect to sex, age, structural response, and loading history.
In order to meet sub-objectives 1 and 2, full-scale frontal sled tests were performed on three different human surrogates: the 50th percentile male Hybrid III (HIII) ATD, the 50th percentile male Test Device for Human Occupant Restraint (THOR-M) ATD, and approximately 50th percentile male post-mortem human surrogates (PMHS). All surrogates were tested under three safety restraint conditions: knee bolster (KB), KB and steering wheel airbag (KB/SWAB), and knee bolster airbag and SWAB (KBAB/SWAB). The kinematic, lower extremity, abdominal, thoracic, and neck responses were then compared between surrogates and restraint conditions. In order to assess biofidelity, the ATD responses were compared to the PMHS responses. For both the kinematic and thoracic responses, the HIII and THOR-M had comparable biofideltiy. However, the HIII responses were slightly more biofidelic. The ATDs experienced similar lower extremity kinetics, but very different kinetics at the upper and lower neck due to differences in design. Evaluation of the different restraint conditions showed that the SWAB and KBAB both affected injury risk. The SWAB decreased head injury risk for all surrogates, and increased or decreased thoracic injury risk, depending on the surrogate. The KBAB decreased the risk of femur injury, but increased or decreased tibia injury risk depending on the surrogate and injury metric used to predict risk.
In order to meet sub-objective 3, the tensile material properties of human rib cortical bone and the structural properties of whole ribs were quantified at strain rates similar to those observed in frontal impacts. The rib cortical bone underwent coupon tension testing, while the whole ribs underwent bending tests intended to simulate loading from a frontal impact. The rib material properties accounted for less than 50% of the variation observed in the whole rib structural properties, indicating that other factors, such as rib geometry, were also influencing the structural response of whole ribs. Age was significantly negatively correlated with the modulus, yield stress, failure strain, failure stress, plastic strain energy density, and total strain energy density. However, sex did not significantly influence any of the material properties. Cortical bone material properties were quantified from the ribs that underwent the whole rib bending tests and subject-matched, untested (control) ribs in order to evaluate the effect of loading history on material properties. Yield stress and yield strain were the only material properties that were significantly different between the previously tested and control ribs.
The results of this dissertation can guide ATD and safety restrain design. Additionally, this dissertation provides human surrogate response data and rib material property data for the validation of finite element models, which can then be used to evaluate injury mitigation strategies for MVCs. / PHD / Frontal motor vehicle collisions (MVCs) resulted in 10,813 fatalities and 937,000 injuries in 2014, which is more than any other type of MVC. In order to mitigate the injuries and fatalities resulting from MVCs, new safety restraint technologies, e.g., seat belts, and more biofidelic (human-like) anthropomorphic test devices (ATDs), i.e., crash test dummies, have been developed. However, the biofidelity of these new ATDs must be evaluated, and the mechanisms of injury must be understood in order to accurately predict injury. Evaluating the biomechanical response, injury mechanisms, and injury threshold of the thorax (chest) are particularly important because the thorax is one of the most frequently injured body regions in MVCs. Furthermore, sustaining a severe thoracic injury in an MVC significantly increases the risk of death.
The overall objective of this dissertation was to evaluate the biomechanical responses of human surrogates under various frontal loading conditions. This objective was divided into three sub-objectives: 1) to evaluate the biofidelity of the current frontal impact ATDs, 2) to evaluate the effect of different safety restraints on occupant responses, and 3) to evaluate rib material properties with respect to sex, age, structural response, and loading history.
In order to meet sub-objectives 1 and 2, frontal crash tests were simulated in the laboratory using a crash sled. These sled tests were performed on three different human surrogates: the Hybrid III (HIII) ATD, the Test Device for Human Occupant Restraint (THOR-M) ATD, and post-mortem human surrogates (PMHS), i.e., cadavers. All surrogates were tested under three safety restraint conditions: knee bolster (KB), KB and steering wheel airbag (KB/SWAB), and knee bolster airbag and SWAB (KBAB/SWAB). The kinematic (body movements), lower extremity, abdominal, thoracic, and neck responses were then compared between surrogates and restraint conditions. In order to assess biofidelity, the ATD responses were compared to the PMHS responses. For both the kinematic and thoracic responses, the HIII and THOR-M had comparable biofideltiy. However, the HIII responses were slightly more biofidelic. The ATDs experienced similar lower extremity kinetics (forces and moments), but very different kinetics at the upper and lower neck due to differences in design. Evaluation of the different restraint conditions showed that the SWAB and KBAB both affected injury risk. The SWAB decreased head injury risk for all surrogates, and increased or decreased thoracic injury risk, depending on the surrogate. The KBAB decreased the risk of femur injury, but increased or decreased tibia injury risk depending on the surrogate and how injury risk was predicted.
In order to meet sub-objective 3, the material properties of human rib cortical bone and the structural response of whole ribs were quantified under experimental conditions reminiscent of what the bone would experience during a frontal impact. The rib cortical bone underwent material testing, while the whole ribs underwent bending tests intended to simulate a frontal impact. The rib material properties only partially influenced the structural response of the whole rib. This indicated that other factors, such as rib shape and thickness, were also influencing the structural response. Age was correlated to a decrease in several material properties. However, there was no significant difference between male and female material properties. Some differences in material properties were observed in cortical bone from fractured and intact ribs, indicating that the fracture influenced the rib material properties.
results of this dissertation can guide ATD and safety restrain design. Additionally, this dissertation provides human surrogate response data and rib material property data for finite element (computer) models, which can then be used to evaluate injury prevention strategies for MVCs.
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Αναγνώριση προπορευόμενου οχήματος με ψηφιακή επεξεργασία εικόναςΣκόδρας, Ευάγγελος 03 July 2009 (has links)
Η ανάπτυξη ενός ενσωματωμένου στο όχημα συστήματος υποβοήθησης του οδηγού για αποφυγή συγκρούσεων με άλλα οχήματα, βρίσκεται τελευταία στο επίκεντρο του ενδιαφέροντος. Στα συστήματα αυτά η αξιοπιστία αποτελεί ένα πολύ σημαντικό παράγοντα. Στην παρούσα εργασία αναπτύσσεται ένα σύστημα αναγνώρισης προπορευόμενου οχήματος βασισμένο σε εικόνες οι οποίες λαμβάνονται από βιντεοκάμερα που έχει ενσωματωθεί στο όχημα. Η μεθοδολογία την οποία επιλέξαμε να εργαστούμε περιλαμβάνει τον εντοπισμό των κόκκινων εικονοστοιχείων στην εικόνα και τη δημιουργία της αντίστοιχης δυαδικής εικόνας. Στη συνέχεια, με μορφολογική επεξεργασία της δυαδικής εικόνας εντοπίζουμε τις περιοχές που αντιστοιχούν στα πιθανά φανάρια του οχήματος. Με βάση τα σημεία των πιθανών φαναριών καθορίζουμε την περιοχή στην οποία περικλείεται το όχημα. Για την επιβεβαίωση της ύπαρξης οχήματος στην περιοχή αυτή, εκτελούμε έναν έλεγχο συμμετρίας βασιζόμενοι στην ομοιότητα των υποεικόνων και συνεχίζουμε με τον προσεγγιστικό υπολογισμό της απόστασής του. Τέλος, παρουσιάζουμε τα αποτελέσματα της μεθόδου, τα συμπεράσματα που προέκυψαν και προτείνουμε κατευθύνσεις για μελλοντικές βελτιώσεις. / Developing on-board automotive driver assistance systems aiming to alert drivers about possible collision with other vehicles has attracted a lot of attention lately. In these systems, robust and reliable vehicle detection is a critical step. In this work a vehicle detection system is developed based on video frames grabbed by a camera mounted on the vehicle. Vehicle detection is mainly based on the detection of its red rear-lights. First we detect all red pixels of the frame and create the corresponding binary image (mask). Then we detect the areas that possibly constitute vehicle’s rear-lights by performing morphological binary image processing. Based on that, we determine the boundary of the vehicle. To verify the presence of the vehicle in this area, we perform a symmetry test based on sub-image similarity. Finally, we present some experimental results and give directions for future improvements.
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Komplexní systém pro analýzu silničních nehod typu střet vozidla s motocyklem / Comprehensive System for Road Accident Analysis - Collision Between Vehicle and MotorcycleSlepánek, Petr January 2019 (has links)
This dissertation describes the issue of a complex system for analyzing the collision of a motorcycle with another vehicle and suggests a suitable methodology for solving this type of traffic accident. It summarizes the current knowledge in the field of motorcycle accidents withother vehicles, including their statistics and categorization. The author statistically evaluates accidents by their causes and proposes a methodology for solving individual types of motorcycle collisions with vehicles. To supplement and refine the input data for the analysis of road accidents involving motorcycles, a set of author’s own measurements made on different types of motorcycles is included. The thesis contains measurements of their acceleration, deceleration and avoidance maneuvers. Other actual contributions of the thesis are represented also by flowcharts, offering a comprehensive approach to solving individual types of colissions of motorcycles with other vehicles.
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Wildlife-vehicle collisions : An evaluation of the mitigation effect by ecoducts and fauna bridges in SwedenRietz, Anna January 2023 (has links)
The occurrence of wildlife vehicle collisions (WVCs) is an increasing problem in Sweden with a calculated increase of 45 percent from 2015 to 2022. The highest measured number of WVCs occurred in 2021 with over 67,000 reported incidents, where only the payment for the search of wounded animals were approximately 60 million Swedish crowns. The Swedish transport agency works actively with the problem by constructing several types of wildlife passages to mitigate the increasing problem, inter alia, ecoducts and fauna bridges. The aim of this study was to evaluate the mitigation effect of wildlife passages, in this case ecoducts and fauna bridges. In addition, were also the spatial extent of the mitigation effect together with the relationship between mitigation effect and the annual daily traffic (ADT) evaluated. The evaluation of mitigation effect was conducted by the usage of several types of geographical information systems (GIS) tools in the software ArcGIS Pro. A selection of seven passages was made, based on several requirements and each passage was assigned a study area with an area of 100 square kilometers. The mitigation effect was initially determined by conducting an Emerging hot spot analysis, categorizing the result into showing trend of decrease or showing no trend of decrease. The spatial extent of the mitigating effect was evaluated through the Emerging hot spot results while the relation between ADT and WVCs was evaluated in an overlay analysis. Two of the passages were concluded as to having a mitigating effect, three passages were concluded as to showing no mitigating effect and two passages were excluded from further evaluation due to high uncertainty in the results. At the passages with stated mitigating effect were the spatial extent of effect shown in the whole study area. The result showed no evident correlation between ADT and mitigating effects which led to further reflections on the degree of influence that ADT has on the occurrence of WVCs.
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