To see the other types of publications on this topic, follow the link: Traffic counts.
Dissertations / Theses on the topic 'Traffic counts'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Traffic counts.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Nobe, Steve. "On-line estimation of traffic split parameters based on lane counts." Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/280239.
Full textAbstract:
Adaptive traffic control systems need to continuously monitor traffic conditions and predict immediate traffic conditions to respond to changes in both recurrent and nonrecurrent traffic patterns. One measure of traffic conditions is the number of turning vehicles at intersections and freeway offramps. Split parameters may be estimated from the numbers of turning vehicles, and along with upstream traffic counts, these may be used to predict the numbers of downstream vehicle arrivals. This study develops several responsive methods to estimate split parameters for four-legged intersections and freeway segments from vehicle counts. For intersections, these methods depend on the geometric layout of the intersection and the signal stage. The vehicle counts are collected by signal stages and lanes. The split parameters or turning proportions are estimated for each signal stage and, then they are combined to estimate the turning proportions for the entire interval. Some methods need counts for only one cycle to estimate turning proportions while others need additional data. For those methods that need additional data, four closed-form estimation methods are developed. Two methods need prior turning proportion estimates: (1) maximum entropy (ME) and (2) generalized least-squared error (GLS). The other methods require counts for three cycles: (3) least-squared error (LS) and (4) least-squared error/generalized least-squared error (LS/GLS). Results from these methods are compared with each other. The ME, GLS and LS methods which use cycle counts are also developed and their results are compared with the results of their stage-count counterparts. For freeway segments, a virtual box method for consistent vehicle counting is developed. Three split parameter estimation methods are developed for freeway segments. One method, GLS, uses counts, from one virtual box and requires prior split parameter estimates. The other methods, LS and GLS/LS, need several virtual boxes, depending on the number of interchanges in the freeway segment. Split parameter estimation approaches are also developed for small road networks by combining split parameters from individual intersections and freeway segments.
2
Chang, David Keali'i. "Evaluation of the Accuracy of Traffic Volume Counts Collected by Microwave Sensors." BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5486.
Full textAbstract:
Over the past few years, the Utah Department of Transportation (UDOT) has developed a system called the Signal Performance Metrics System (SPMS) to evaluate the performance of signalized intersections. This system currently provides data summaries for several performance measures including: 1) Purdue Coordination Diagram, 2) Speed, 3) Approach Volume, 4) Purdue Phase Termination Charts, 5) Split Monitor, 6) Turning Movement Volume Counts, 7) Arrivals on Red, and 8) Approach Delay. There is a need to know the accuracy of the data that are being collected by the Wavetronix SmartSensor Matrix and displayed in the SPMS. The TAC members determined that the following factors would affect the accuracy of radar-based traffic sensors the most: sensor position, number of approach lanes, and volume level. The speed limit factor was added to the study after most of the data collection was completed. The purpose of this research was to collect data at various intersections to determine the accuracy of the data collected by the Wavetronix SmartSensor Matrix.A Mixed Model Analysis of Variance (ANOVA) was employed to analyze the effects that each factor had on the accuracy of the traffic volume count. A total of 14 tests were performed to examine the effects of the factors on traffic volume count accuracy. The sensor position factor was not found to be a statistically significant factor affecting the accuracy of traffic volume counts. The effect of speed limit on traffic volume count accuracy was determined to be inconclusive due to the lack of samples to be tested. The remaining two factors, volume level and number of approach lanes, were found to have a statistically significant effect on the accuracy of traffic volume counts. Based on these two factors, a matrix was created to meet the needs of UDOT to present accuracy values on the SPMS website. This matrix includes the mean, 95 percent confidence interval of the mean, standard deviation, number of samples, and the minimum number of samples needed.
3
Kang, Dong Hun. "Multi-commodity flow estimation with partial counts on selected links." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4693.
Full textAbstract:
The purpose of this research is to formulate a multi-commodity network flow model
for vehicular traffic in a geographic area and develop a procedure for estimating traffic
counts based on available partial traffic data for a selected subset of highway links. Due
to the restriction of time and cost, traffic counts are not always observed for every
highway link. Typically, about 50% of the links have traffic counts in urban highway
networks. Also, it should be noted that the observed traffic counts are not free from
random errors during the data collection process. As a result, an incoming flow into a
highway node and an outgoing flow from the node do not usually match. They need to
be adjusted to satisfy a flow conservation condition, which is one of the fundamental
concepts in network flow analysis.
In this dissertation, the multi-commodity link flows are estimated in a two-stage
process. First, traffic flows of "empty" links, which have no observation data, are filled
with deterministic user equilibrium traffic assignments. This user equilibrium
assignment scheme assumes that travelers select their routes by their own interests
without considering total cost of the system. The assignment also considers congestion
effects by taking a link travel cost as a function of traffic volume on the link. As a result,
the assignment problem has a nonlinear objective function and linear network constraints.
The modified Frank-Wolfe algorithm, which is a type of conditional gradient method, is
used to solve the assignment problem. The next step is to consider both of the observed traffic counts on selected links and
the deterministic user equilibrium assignments on the group of remaining links to
produce the final traffic count estimates by the generalized least squares optimization
procedure. The generalized least squares optimization is conducted under a set of
relevant constraints, including the flow conservation condition for all highway
intersections.
4
Chiddarwar, Arjun. "Application Of Computer Vision Algorithms For Uninterrupted Traffic Monitoring Based On Aerial Images And Videos." University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1551969896901775.
Full text
5
RICAURTE, ANGELICA JUDITH SILVA. "ESTIMATING FREIGHT VEHICLES O-D MATRICES FROM TRAFFIC COUNTS IN THE METROPOLITAN REGION OF RIO DE JANEIRO." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=32423@1.
Full textAbstract:
PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
Com o crescimento das indústrias e a competitividade entre os mercados o transporte de cargas urbano tem-se considerado fundamental para a economia, mas a importância de sua relação direta com a vida das pessoas nas cidades tem ocasionado que exista maior congestionamento nas regiões centrais. É, por isso, que é importante ter o conhecimento sobre o deslocamento das cargas urbanas dentro da Região Metropolitana do Rio de Janeiro – RMRJ. Este trabalho trata de estimar matrizes origem destino (O-D) a partir de contagens de fluxos observadas na rede. Estas contagens foram realizadas para dois tipos de horários considerados importantes por motivo de restrições de circulação, sendo estes o pico da manhã (7:00 às 8:00) e pico da tarde (17:30 às 18:30). Após fazer uma revisão bibliográfica sobre o assunto, o trabalho define entre os métodos conhecidos o que foi considerado mais adequado para a estimativa da matriz OD. Decidiu-se pelo método desenvolvido por Nielsen (1998) denominado como Método de Caminho Único - SPME. O Método foi aplicado na rede viária do plano diretor de transportes urbanos da Região Metropolitana do Rio de Janeiro (PDTU-RMRJ), usando o software TransCAD.
With the growth of industries and competitiveness between markets, the urban freight transport has been considered fundamental for the economy, but the importance of their direct relationship to the lives of people in cities has resulted in more congestion in the central regions. It is therefore important to have knowledge about the movement of urban freight inside the Metropolitan Area of Rio de Janeiro - MARJ. This work try to estimate origin destination matrices (O-D) from flows observed on the network. These counts were done for two types of times considered important for reasons of traffic restrictions, which are the peak of the morning (7:00 - 8:00) and late peak (17:30 - 18:30). After doing a literature review on the issue, the work defines between the known methods the one that was considered most appropriate for the estimation of O-D matrix. Decided for the method developed by Nielsen (1998) termed as Single Path Matrix Estimation - SPME. The method was applied to the road network of the master plan of the urban transport in the Metropolitan Area of Rio de Janeiro (PDTU-RMRJ), using software TransCAD.
6
Lei, Peng. "A Linear Programming Method for Synthesizing Origin-Destination (O-D) Trip Tables from Traffic Counts for Inconsistent Systems." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36860.
Full textAbstract:
Origin-Destination (O-D) trip tables represent the demand-supply information of each directed zonal-pair in a given region during a given period of time. The effort of this research is to develop a linear programming methodology for estimating O-D trip tables based on observed link volumes. In order to emphasize the nature of uncertainty in the data and in the problem, the developed model permits the user's knowledge of path travel time to vary within a band-width of values, and accordingly modifies the user-optimality principle. The data on the observed flows might also not be complete and need not be perfectly matched. In addition, a prior trip table could also be specified in order to guide the updating process via the model solution. To avoid excessive computational demands required by a total numeration of all possible paths between each O-D pair, a Column Generation Algorithm (CGA) is adopted to exploit the special structures of the model. Based on the known capacity of each link, a simple formula is suggested to calculate the cost for the links having unknown volumes. An indexed cost is introduced to avoid the consideration of unnecessary passing-through-zone paths, and an algorithm for solving the corresponding minimum-cost-path problem is developed. General principles on the design of an object-oriented code are presented, and some useful programming techniques are suggested for this special problem. Some test results on the related models are presented and compared, and different sensitivity analyses are performed based on different scenarios. Finally, several research topics are recommended for future research.Master of Science
7
Jiang, Zhuojun. "Incorporating image-based data in AADT estimation methodology and numerical investigation of increased accuracy /." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1123724063.
Full textAbstract:
Thesis (Ph. D.)--Ohio State University, 2005.Title from first page of PDF file. Document formatted into pages; contains xi, 184 p.; also includes graphics (some col.). Includes bibliographical references (p. 158-167). Available online via OhioLINK's ETD Center
8
Emery, Justin. "La ville sous électrodes : de la mesure à l'évaluation de la pollution atmosphérique automobile. : vers une simulation multi-agents du trafic routier en milieu urbain." Thesis, Dijon, 2016. http://www.theses.fr/2016DIJOL018/document.
Full textAbstract:
À partir des enquêtes, le trafic n’est pas une donnée, mais il est plutôt construit à partir d’hypothèses portant sur les relations entre des origines et des destinations. En vue de reconstruire un trafic routier plus proche de la mesure, et sur un ensemble de tronçons routiers plus important, il apparait alors intéressant de partir de données de comptages issues de capteurs urbains. Notre postulat de départ part de ce constat. L’insertion de ces données d’observations du trafic routier fournit l’opportunité d’expérimenter les potentiels d’exploitations des capteurs pour estimer les niveaux de Pollution Atmosphérique Automobile (PAA) à l’échelle intraurbaine. Cependant, il est alors nécessaire de modifier la nature de la mesure en vue d’extraire une information sur la circulation routière, ce qui a été envisagé ici à travers la construction d’un modèle de simulation multi-agents. D’une manière plus générale, en partant de la donnée, c’est une démarche de construction de la connaissance sur les émissions de PAA qui est abordée tout au long de ce travail. La mise en œuvre de la démarche de modélisation SCAUP (Simulation multi-agents à partir de Capteurs Urbains pour la Pollution atmosphérique automobile) a été réalisée en trois temps : 1. En se focalisant sur les dispositifs de quantification du trafic routier à travers les capteurs urbains ; 2. En proposant une démarche de modélisation et de simulation de ces données pour le trafic routier ; 3. En se rattachant aux référentiels nationaux utilisés par les AASQA pour le calcul des émissions de PAA. L’ensemble se lie et s’intègre au sein d’une matrice technique qui constitue la colonne vertébrale de ce manuscrit à travers trois dispositifs interdépendants : la quantification, la modélisation et l’évaluation. Ce travail s’inscrit dans une démarche expérimentale de simulation du trafic routier pour le calcul des émissions de PAA. Parrainé par l’AASQA locale ATMOSF’AIR BOURGOGNE, il s’inscrit aussi dans une optique de recherche appliquée en appui de ces organismes en charge de la surveillance de la qualité de l’air. À l’heure où le big data entre dans de nouveaux questionnements quant aux capacités des chercheurs à en extraire une connaissance, nous proposons une démarche géographique en vue de replacer la donnée au centre d’une démarche de simulation originale du trafic routier (data-driven)Based on surveys, traffic is constructed from assumptions about the relationship between origins and destinations. In order to rebuild a road traffic wich would be closer to observation and on a wider set of road sections, it appears interesting to use counting data from urban sensors : this is our starting point of view. The insertion of these in-situ dataset in the road traffic measurement provides the opportunity to experience the potential of sensors to estimate Traffic Air Pollution (TAP) levels at the intraurban scale. However, this requires to change the nature of these estimation, here through the construction of a model of multi-agents simulation, in order to extract more information on the road traffic. More generally, this work can be seen as a a knowledge building approach on TAP emisssions which is discussed throughout this work. The implementation of the SCAUP (multi-agent simulation from Urban sensors for traffic air pollution) approach was developped in three stages: 1. Focusing on the quantification of road traffic devices through urban sensors; 2. Proposing a modeling approach for road traffic data simulation ; 3. Using as a reference the national framework used by AASQA to calculate RTA emissions. All is integrated within a technical matrix that forms the spine of the manuscript through three interrelated systems: quantification, modeling and evaluation. This work is part of an experimental approach dedicated to the calculation of TAP emissions based on traffic simulations. Sponsored by the ATMOSF’AIR BOURGOGNE local AASQA, this work could also be used in an operational mode for these organizations in charge of the air quality monitoring. At a time when the big data enters into new questions about the ability of researchers to extract knowledge, we propose a geographical approach that enables to replace the data in the center of an original road traffic simulation approach (data- driven)
9
Poon, Po-wan Shirley, and 潘寶雲. "Reducing traffic in country parks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B43894446.
Full text
10
Poon, Po-wan Shirley. "Reducing traffic in country parks." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B23339275.
Full text
11
Coeymans-Avaria, Juan Enrique. "Traffic signal systems in a developing country." Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305939.
Full text
12
Schneiderman, Jacqueline Dova. "Analysis of landscape characteristics surrounding deer vehicle accidents in St. Louis County, Missouri." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/5681.
Full textAbstract:
Thesis (M.S.)--University of Missouri-Columbia, 2008.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on September 15, 2008) Includes bibliographical references.
13
Bennett, Rob. "The management of road traffic in a rural county : Herefordshire 1919-1939." Thesis, Coventry University, 2008. http://eprints.worc.ac.uk/583/.
Full textAbstract:
The period between the two World Wars, 1919 to 1939, saw a major expansion in the use of motor vehicles on the roads of Britain and a consequent increase in road accidents and fatalities. Studies of road transport in this period have concentrated largely on the expanding urban areas. Little detailed work has been completed in rural areas. This study goes some way to fill this gap in our knowledge. It will examine the rural county of Herefordshire where the use of motor vehicles did increase greatly, although not to the extent of the country as a whole. This thesis will address the management of the safety of road traffic which was exercised by the County Council in the inter war years. The heart of the study is the evaluation of the size of the problem and the efforts of the County Surveyor to improve the safety of the county road network. Increasing use of the road network was encouraged by the decline in use of the rail network. The A40 trunk road in the south of the county saw traffic increases of approximately one and a half times over the two decades. However the secondary roads such as the B4214 north of Bromyard saw much greater increase. Cars increased by six and three quarter times whilst lorries by the even larger margin of nine times over the two decades. The improvements carried out to the county road network consisted of road widening, rather than major road realignments. The County Council members were strongly resistant to the loss of agricultural land. However significant new improvements to the road surface were effected throughout the county albeit in short lengths. Four different types of road surface were tried. In fact the county was at the forefront of road surface development in this period. The County Surveyor’s preferred choice was a bitumen/stone mix laid cold which became the accepted solution for the country as a whole in the 1930s. The attitude adopted by the police force, essentially reactive, in the management of road safety will be examined. Whilst traffic volumes increased in the inter-war years there was no corresponding increase in the 1930s in the recorded number of fatal road accidents. The thesis will conclude with an assessment of the degree of public satisfaction with the efforts of the County Surveyor and the Chief Constable in maintaining a safe county road network in the inter-war years. The public, through the medium of the press and the County Council minutes, indicated that they considered that the efforts of the Surveyor and Chief Constable were acceptable.
14
Blaiklock, Philip. "A portable, wireless inductive-loop vehicle counter." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34737.
Full textAbstract:
This thesis descries the evolution and testing of a fully portable, inductive loop vehicle counter system. As a component of the NFS Embedded Distributed Simulation for Transportation System Management project, the system's cellular modem transmits real-time data to servers at Georgia Institute of Technology. From there, the data can be fed into simulations predicting travel behavior. Researchers revised both the detector circuit, and the temporary, reusable loop pad several times over multiple rounds of field testing.
The final tested version of this system demonstrates the efficacy of uncommonly small
inductive loops. When paired with a reliable data transmission channel, the system was
shown to capture nearly 96% of actual through traffic.
15
Lu, Huabo. "Sender cover traffic to counter an improved Statistical Disclosure Attack." Thesis, Wichita State University, 2011. http://hdl.handle.net/10057/5040.
Full textAbstract:
The statistical disclosure attack (SDA) is quite an effective method for attackers
to go against an anonymity system and to reveal the information behind it. It targets
at a particular anonymity system user, tries to find its sending/receiving relationship with
others after a long term observation. In this thesis, we first make an improvement for SDA,
using weighted mean instead of the orginal arithmetic mean to calculate the cumulative
observed receiver popularity in order to get a more precise value of the attack result. Second,
we present an analysis for the effectiveness of the sender generated cover traffic, showing
that employing this kind of cover traffic helps little on protecting anonymity system users
against a sophisticated attacker. The analysis also validates an earlier empirical result of the
ineffectiveness of sender generated cover traffic.Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science
16
Roll, Josh Frank. "Bicycle Traffic Count Factoring: An Examination of National, State and Locally Derived Daily Extrapolation Factors." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/998.
Full textAbstract:
Since nearly the beginning of the wide spread adoption of the automobile, motorized traffic data collection has occurred so that decision makers have information to plan the transportation system. Widespread motorized traffic data collection has allowed for estimating traffic volumes using developed extrapolation methods whereby short-term counts in sample locations can be expanded to longer periods. As states and local planning agencies make investments in bicycle infrastructure and count programs develop, similar extrapolation methods will be needed. The only available guidance on extrapolating bicycle counts comes from the National Bicycle and Pedestrian Documentation Project (NBPDP), yet no validation of these factors have been done to assess their usability in specific area. Using bicycle traffic count data from the Central Lane Metropolitan Planning Organization Count Program in Oregon, this research demonstrates that using study area data to generate time-of-day factors produces results with less error compared to application of the NBPDP time-of-day factors. Factors are generated in two separate way in order to reduce error from estimating daily bicycle volumes. Factors groups are developed using bicycle facility type where counts are collected. This research also seeks to add to the literature concerning bicycle travel patterns by using study area data to establish a university travel pattern exemplified by a flat hourly distribution from morning to evening.
17
Heidaripak, Samrend. "PREDICTION OF PUBLIC BUS TRANSPORTATION PLANNING BASED ON PASSENGER COUNT AND TRAFFIC CONDITIONS." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-53408.
Full textAbstract:
Artificial intelligence has become a hot topic in the past couple of years because of its potential of solving problems. The most used subset of artificial intelligence today is machine learning, which is essentially the way a machine can learn to do tasks without getting any explicit instructions. A problem that has historically been solved by common knowledge and experience is the planning of bus transportation, which has been prone to mistakes. This thesis investigates how to extract the key features of a raw dataset and if a couple of machine learning algorithms can be applied to predict and plan the public bus transportation, while also considering the weather conditions. By using a pre-processing method to extract the features before creating and evaluating an k-nearest neighbors model as well as an artificial neural network model, predicting the passenger count on a given route could help planning of the bus transportation. The outcome of the thesis was that the feature extraction was successful, and both models could successfully predict the passenger count based on normal conditions. However, in extreme conditions such as the pandemic during 2020, the models could not be proven to successfully predict the passenger count nor being used to plan the bus transportation.
18
Mohammed, Taqhiuddin. "Designing an Emergency Traffic Signal System (ETSS): A Case Study of an Intersection Along U.S.1, Fairfax County, Virginia." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/33411.
Full textAbstract:
Access to highways from a local firehouse is a major problem for emergency services. Motorists often do not see flashing lights or hear sirens from the approaching emergency vehicles (EV) until emergency vehicles reach the highway entrance, often too late to take appropriate action. Many locations have installed special signals called emergency traffic signal systems (ETSS) or used signal preemption to notify motorists and to stop traffic to allow the emergency vehicle to enter the highway safely. This thesis will examine the effectiveness of one such installation at the intersection along U.S.1 at Beedo Street and some of the impacts it has on highway traffic. The evaluation of the said installation is carried out in terms of delay to EV; conflict potential between EV and other vehicles and response of the motorists to the ETSS. This thesis also proposes two alternative designs of ETSS to improve the existing signal system.Master of Science
19
VLASSOVA, LIDIA. "ESTIMATING STREET-LEVEL COMMUTER FLOWS AND THEIR RACIAL COMPOSITION IN HAMILTON COUNTY, OHIO." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1028570153.
Full text
20
Pan, Tao. "Assignment of Estimated Average Annual Daily Traffic Volumes on All Roads in Florida." [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002481.
Full text
21
Ouafi, Rachid. "Analyse et contrôle des réseaux de trafic urbain par la méthode de Frank-Wolfe." Paris 6, 1988. http://www.theses.fr/1988PA066453.
Full textAbstract:
La méthode de Frank Wolfe offre une approche efficace pour la résolution des programmes convexes avec contraintes linéaires. Dans le contexte des réseaux de transport l'algorithme se réduit à une série de problèmes de plus court chemin et de recherches unidimensionnelles. Nous présentons une approche unifiée de la résolution d'une large variété de problèmes lies au système de planification du trafic urbain par la méthode de Frank Wolfe. Enfin, nous proposons une modification de l'algorithme de Frank Wolfe pour la résolution du problème de l'affectation du trafic urbain.
22
Vallurupalli, Rama Krishna. "New methods to estimate average annual daily traffic using data from permanent count stations." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq28838.pdf.
Full text
23
Hecht, Marie B. "A comparison of Bayesian and classical statistical techniques used to identify hazardous traffic intersections." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276795.
Full textAbstract:
The accident rate at an intersection is one attribute used to evaluate the hazard associated with the intersection. Two techniques traditionally used to make such evaluations are the rate-quality technique and a technique based on the confidence interval of classical statistics. Both of these techniques label intersections as hazardous if their accident rate is greater than some critical accident rate determined by the technique. An alternative technique is one based on a Bayesian analysis of available accident number and traffic volume data. In contrast to the two classic techniques, the Bayesian technique identifies an intersection as hazardous based on a probabilistic assessment of accident rates. The goal of this thesis is to test and compare the ability of the three techniques to accurately identify traffic intersections known to be hazardous. Test data is generated from an empirical distribution of accident rates. The techniques are then applied to the generated data and compared based on the simulation results.
24
Anderson, Linda K. "Deer-Vehicle Accident Hotspots in Northwest Clackamas County, Oregon." PDXScholar, 2006. https://pdxscholar.library.pdx.edu/open_access_etds/4968.
Full textAbstract:
Road-kill of wildlife is common on Portland, Oregon's suburban fringe where development has increased road densities and traffic volume in rural areas. I identify the spatial and temporal patterns of black-tailed deer (Odocoileus hemionus columbianus) deer-vehicle accidents (DVA) at the suburban/rural interface of developing northwest Clackamas County using deer carcass pickup reports for county maintained roads for 1997-2004 and Oregon Department of Transportation deer-vehicle accident reports for 1996-2004. No black-tailed deer DVA models exist in the literature.
DVA increased 121% from 1997 to 1999 followed by a 26% decline by 2004. The initial DVA increase appears related to population growth and development into rural areas, an increase in the average daily vehicle-trip distance, and deer immigration from public lands. The subsequent decline appears related to DVA-induced decreases in deer populations, year-around hunting permits, growing predator populations, and fawning habitat loss.
Temporal OVA patterns for black-tailed deer show a minor peak in June-July and a major peak in October-November. Forty-two percent of DVA occur during the rut/hunt months of September, October, and November. This pattern corresponds to the black-tail's annual cycle and resembles patterns reported for white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus columbianus). Weekly DVA increased from a low on Sunday to a high on Friday and Saturday. DVA showed two daily peaks at 0500-0700 and 1800-2200, corresponding to dawn and dusk when deer activity is highest.
I identified 19 DVA hotspots with 16-27 DVA using CrimeStat III statistical clustering software. Hotspots occurring in rut/hunt months were separate from hotspots occurring in nonrut/nonhunt months. Similar to white-tailed and mule deer, black-tailed DVA hotspots commonly occurred where roads intersect or parallel water features, large forest blocks, and other areas of cover, or separate food sources from cover. Sixty-five percent of DVA occurred outside of hotspots with ≥ 10 DVA.
Deer-vehicle accidents have important ecological and economic costs and are frequent on northwest Clackamas County roads. Additional research supported by multi-agency carcass pickup repo1ting and the acquisition of precise DV A locations using a Global Positioning System (GPS) is needed to better identify wildlife movement corridors.
25
Ladino, lopez Andrés. "Traffic state estimation and prediction in freeways and urban networks." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAT016/document.
Full textAbstract:
La centralisations du travail, la croissance économique et celle de la population autant que l’urbanisation continue sont les causes principales de la congestion. Lors que les villes s’efforcent pour mettre à jour leurs infrastructures du trafic, l’utilisation de nouvelles techniques pour la modélisation, l’analyse de ces systèmes ainsi que l’intégration des mega données aux algorithmes aident à mieux comprendre et combattre les congestions, un aspect crucial pour le bon développement de nos villes intelligentes du XXIe siècle. Les outilsd’assistance de trafic spécialement conçus pour détecter, prévoir et alerter des conditions particulières sont très demandés dans nos jours.Cette recherche est consacrée au développement des algorithmes pour l’estimation et la prédiction sur des réseaux de trafic routier. Tout d’abord, nous considérons le problème de prévision à court terme du temps de trajet dynamique basé sur des méthodes pilotées par les données. Nous proposons deux techniques de fusion pour calculer les prévisions à court terme. Dans un première temps, nous considérons la matrice de covariance d’erreur et nous utilisons ses informations pour fusionner les prévisions individuelles créées á partir de clusters. Dans un deuxième temps, nous exploitons les mesures de similarité parmi le signal á prédire et des clusters dans l’histoire et on propose une fusion en tant que moyenne pondérée des sorties des prédicteurs de chaque cluster. Les résultats des deux méthodes on été validés dans le Grenoble Traffic Lab, un outil en temps réel qui permet la récupération de données d’une autoroute d’environ (10.5Km) qui couvre le sud de Grenoble.Postérieurement nous considérons le problème de reconstruction de la densité / et le débit de façon simultanée à partir de sources d’information hétérogènes. Le réseau de trafic est modélisé dans le cadre de modèles de trafic macroscopique, où nous adoptons l’équation de conservation Lighthill-Whitham-Richards avec un diagramme fondamental linaire par morceaux. Le problème d’estimation repose sur deux principes clés. Dans un premier temps, nous considérons la minimisation des erreurs entre les débits et les densités mesurés et reconstruits. Finalement, nous considérons l’état d’équilibre du réseau qui établit la loi de propagation des flux entrants et sortants dans le réseau. Tous les principes sont intégrés et le problème est présenté comme une optimisation quadratique avec des contraintes d’égalité a fin de réduire l’espace de solution des variables à estimer. Des scénarios de simulation basés sur des données synthétiques pour un réseau de manhattan sont fournis avec l’objectif de valider les performances de l’algorithme proposéCentralization of work, population and economic growth alongside continued urbanization are the main causes of congestion. As cities strive to update or expand aging infrastructure, the application of big data, new models and analytics to better understand and help to combat traffic congestion is crucial to the health and development of our smart cities of XXI century. Traffic support tools specifically designed to detect, forecast and alert these conditions are highly requested nowadays.This dissertation is dedicated to study techniques that may help to estimate and forecast conditions about a traffic network. First, we consider the problem Dynamic Travel Time (DTT) short-term forecast based on data driven methods. We propose two fusion techniques to compute short-term forecasts from clustered time series. The first technique considers the error covariance matrix and uses its information to fuse individual forecasts based on best linear unbiased estimation principles. The second technique exploits similarity measurements between the signal to be predicted and clusters detected in historical data and it performs afusion as a weighted average of individual forecasts. Tests over real data were implemented in the study case of the Grenoble South Ring, it comprises a highway of 10.5Km monitored through the Grenoble Traffic Lab (GTL) a real time application was implemented and open to the public.Based on the previous study we consider then the problem of simultaneous density/flow reconstruction in urban networks based on heterogeneous sources of information. The traffic network is modeled within the framework of macroscopic traffic models, where we adopt Lighthill-Whitham-Richards (LWR) conservation equation and a piecewise linear fundamental diagram. The estimation problem considers two key principles. First, the error minimization between the measured and reconstructed flows and densities, and second the equilibrium state of the network which establishes flow propagation within the network. Both principles are integrated together with the traffic model constraints established by the supply/demand paradigm. Finally the problem is casted as a constrained quadratic optimization with equality constraints in order to shrink the feasible region of estimated variables. Some simulation scenarios based on synthetic data for a manhattan grid network are provided in order to validate the performance of the proposed algorithm
26
Mittal, Manoj Sanwarmal. "Assessing the Performance of an Emergency Vehicle Preemption System: A Case Study on U.S. 1 in Fairfax County, Virginia." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/46177.
Full textAbstract:
Highway traffic control systems have been deployed to provide emergency vehicle preemption (EVP) at signalized intersections. Industry and transportation researchers have worked to develop analytical methods to establish the degree of benefit of emergency vehicle preemption to the emergency vehicle (EV) community and the impact on other road user groups. This thesis report illustrates the use of an analytical method to evaluate the potential impacts of EVP related to EV safety, and the potential delay to EVs and vehicles on the side street. The method uses EV-specific conflict point and delay analysis with video and other data collected in a field study conducted in Northern Virginia at the intersection of Southgate Drive and U.S. 1. EV related conflict points are characterized in terms of the EV/auto interaction geometry, the signal display, and the severity of potential crashes. EV related delay is characterized in terms of the EV/auto interaction geometry, the signal display, the level of service and the amount of delay to the EV. The EV/auto interaction, the queue length and the signal display characterize increase in delay to vehicles on the side street. The analysis indicates that the severity of EV-specific conflict points is significantly reduced with EVP. The delay to EV does not change significantly and the delay to the vehicles on the side street auto traffic increases.Master of Science
27
Shuhaibar, Nabeel Khalil. "Road accidents in a developing country : characteristics and causes of accident rates in Kuwait." Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/8185.
Full text
28
Ponnada, Sowjanya VJ. "Identifying Locations with High Rates of Alcohol Related Traffic Crashes in Ohio." University of Dayton / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1335885375.
Full text
29
Avadhani, Umesh D. "Data processing in a small transit company using an automatic passenger counter." Thesis, Virginia Tech, 1986. http://hdl.handle.net/10919/45669.
Full textAbstract:
This thesis describes the work done in the second stage of the implementation of the Automatic Passenger Counter (APC) system at the Roanoke Valley - Metro Transit Company. This second stage deals with the preparation of a few reports and plots that would help the transit managers in efficiently managing the transit system. The reports and plots give an evaluation of the system and service operations by which the decision makers can support their decisions.
For an efficient management of the transit system, data on ridership activity, running times schedule information, and fare revenue is required. From this data it is possible to produce management information reports and summary statistics.
The present data collection program at Roanoke Valleyâ Metro is carried by using checkers and supervisors to collect ridership and schedule adherence information using manual methods. The information needed for efficient management of transit operations is both difficult and expensive to obtain. The new APC system offers the management with a new and powerful tool that will enhance their capability to make better decisions when allocating the service needs. The data from the APC are essential for the transit propertys ongoing planning and scheduling activites. The management could easily quantify the service demands on a route or for the whole system as desired by the user.
Master of Science
30
Sakkhor, Ahmed Nurul Hasan. "Living Condition: : A Case from Developing Country (Bangladesh)." Thesis, Blekinge Tekniska Högskola, Institutionen för fysisk planering, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-16363.
Full textAbstract:
I de seneste år har forskning og udvikling på levende byer udviklet sig på grund af kompleksitet og mangfoldighed af levekårsstandarder. Cities all over the world are growing day by day. Developed countries are trying hard to reach a level where the liveable conditions can be achieved and they are managing this ongoing challenge with a certain standard. Liveable condition means ensuring every aspect of living elements. Fast growing countries like Bangladesh, India, Vietnam, Pakistan etc are developing but unfortunately they can not be considered as the desired liveable condition until now. In this paper, the author will focus on the liveable conditions of one fast growing city of developing countries, which is the capital city of Bangladesh, Dhaka. Det er et af de byområder som står over for mange udfordringer, langt fra at nå til et niveau hvor mennesker kan leve i en levebar situasjon. Det vil bli gjort ved at analysere aktuelle udfordringer og muligheder. På den annen side vil forfatteren også diskutere om ledelses- og samordningsutfordringer mellom multilevelplanmyndigheter. Omdat relatie tussen verschillende autoriteiten noodzakelijk is om te bereiken de wens levende toestand van een stad. Dette vil blive gjort ved at forske i eksisterende planlægningsmodeller, som er foreslået af disse myndigheder. Forfatteren vil diskutere sit eget forslag til nogle af disse problemer, som kan bruges til at nå det ønskede niveau af levende tilstand. The author will also discuss the management and co-ordination challenges between multilevel planning authorities. Omdat relatie tussen verschillende autoriteiten noodzakelijk is om te bereiken de wens levende toestand van een stad. Dette vil blive gjort ved at forske i eksisterende planlægningsmodeller, som er foreslået af disse myndigheder. Forfatteren vil diskutere sit eget forslag til nogle af disse problemer, som kan bruges til at nå det ønskede niveau af levende tilstand. The author will also discuss the management and co-ordination challenges between multilevel planning authorities. Omdat relatie tussen verschillende autoriteiten noodzakelijk is om te bereiken de wens levende toestand van een stad. Dette vil blive gjort ved at forske i eksisterende planlægningsmodeller, som er foreslået af disse myndigheder. Forfatteren vil diskutere sit eget forslag til nogle af disse problemer, som kan bruges til at nå det ønskede niveau af levende tilstand.
31
Zhao, Qi. "Towards Ideal Network Traffic Measurement: A Statistical Algorithmic Approach." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19821.
Full textAbstract:
Thesis (Ph.D)--Computing, Georgia Institute of Technology, 2008.Committee Chair: Xu, Jun; Committee Member: Ammar, Mostafa; Committee Member: Feamster, Nick; Committee Member: Ma, Xiaoli; Committee Member: Zegura, Ellen.
32
Deshpande, Vinit Vinod. "Evaluating the Impacts of Transit Signal Priority Strategies on Traffic Flow Characteristics:Case Study along U.S.1, Fairfax County, Virginia." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/31319.
Full textAbstract:
Transportation engineers and planners worldwide are faced with the challenge of improving transit services in urban areas using low cost means. Transit signal priority is considered to be an effective way to improve transit service reliability and efficiency. In light of the interest in testing and deploying transit signal priority on a major arterial in Northern Virginia, this research focuses on the impacts of transit signal priority in the U.S.1 corridor in Fairfax County in terms of benefits to transit and impacts on other traffic. Using a simulation tool, VISSIM, these impacts were assessed considering a ten second green extension priority strategy.
The results of the simulation analysis indicated that the Fairfax Connector buses benefit from the green extension strategy with little to no impact on the other non-transit traffic. Overall, improvements of 3.61% were found for bus service reliability and 2.64% for bus efficiency, while negative impacts were found in the form of increases in queue lengths on side streets by a maximum value of approximately one vehicle.
Because this research has provided a foundation for the evaluation of transit signal priority for VDOT and Fairfax County engineers and planners, future research can build upon this effort. Areas identified for future research include the provision of priority for the entire bus route; combination of emergency preemption and transit priority strategies; evaluation of other priority strategies using system- wide priority concepts; and the impacts of priority strategies in monetary terms.Master of Science
33
Hamilton, Corey A. "The Determinants of Traffic Citation Revenues on Florida's Clerks of Court and Comptrollers." ScholarWorks, 2017. https://scholarworks.waldenu.edu/dissertations/3164.
Full textAbstract:
In the wake of budgetary restraints, many local government organizations are examining existing sources of revenue to exhaust available streams without increasing constituents' financial burden. Some of these revenue streams include nontraditional sources, such as traffic citations, yet little research has explored the implications of revenue generated from fines from traffic citations. Using the theory of resource dependence as the foundation, the purpose of this study was to explore the relationship between the estimated population of the county, the unemployment rate of the county, and the personal income per capita against the number of traffic citations issued and the Florida Clerk of Court and Comptroller's (FCCC) revenues and budget attributable to traffic citations for 39 of Florida's counties for the years 2005-¬ - 2014. Data were analyzed using multiple linear regression analyses. The results of this study indicate a statistically significant (p < .001) relationship between population and personal income with increases and decreases, respectively, in the issuance of traffic citations and FCCC revenues attributable to traffic citations. Likewise, there was a statistically significant (p < .001) relationship between population and personal income with increases in the FCCC budget associated with traffic citations. Unemployment rate was not statistically associated with the issuance of traffic citations, and FCCC revenues and budget attributable to traffic citations. The findings of this study may promote positive social change by providing legislative awareness that the FCCCs continue to be dependent on the bulk of their revenues, and significant portion of their budget, from a nontraditional revenue source; the traffic citation.
34
Cavelier, Adeline. "Complementarité des protéines de detoxication et trafic intracellulaire." Phd thesis, Université René Descartes - Paris V, 2007. http://tel.archives-ouvertes.fr/tel-00553511.
Full textAbstract:
La coopération fonctionnelle entre le cytochrome P450 3A (CYP3A) et la P-glycoprotéine (P-gp) décrite dans la littérature est un facteur déterminant contribuant à la variabilité de la biodisponibilité de la plupart des médicaments administrés per os. Le CYP3A et la P-gp sont des protéines membranaires dont les localisations respectives communément attribuées sont la membrane du réticulum endoplasmique pour le CYP3A et la membrane plasmique pour la P-gp. Le but de notre étude était une description intégrée au niveau cellulaire du fonctionnement de ces protéines membranaires de détoxication des médicaments et de leurs métabolites, grâce à la détermination de la localisation cellulaire de ces protéines par immunomarquage et par suivi fonctionnel de composés fluorescents, à l'aide de techniques de microscopie à épifluorescence. Le matériel utilisé comprenait des coupes de foie de rat et humain, des hépatocytes en culture primaire ou des lignées cellulaires de fibroblastes de Hamster chinois D/ADX surexprimant la P-gp. Nous avons ainsi démontré que le CYP3A se localise exclusivement au niveau du réticulum endoplasmique, alors que la P-gp est retrouvée au pôle apical des hépatocytes, au niveau des canalicules biliaires et sur la membrane plasmique des fibroblastes. Une colocalisation membranaire des composés et enzymes, synonyme d'une grande efficacité de détoxication, n'a pas été mise en évidence dans les hépatocytes, à cause de difficultés techniques et d'une trop faible fluorescence des substrats utilisés.
35
Tercero, Francisco. "Measuring injury magnitude and patterns in a low-income country : experiences from Nicaragua /." Stockholm, 2007. http://diss.kib.ki.se/2007/978-91-7357-084-8/.
Full text
36
Shrestha, Sajan. "SENSITIVITY OF QUEUE ESTIMATES TO THE SIZE OF THE TIME INTERVAL USED TO AGGREGATE TRAFFIC VOLUME DATA." Cleveland State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=csu1431087335.
Full text
37
Yarbrough, Trevor S. "Retail Change and Light Rail: an Exploration of Business Location Changes Accompanying Commuter Rail Development in Denton County, Texas." Thesis, University of North Texas, 2014. https://digital.library.unt.edu/ark:/67531/metadc700058/.
Full textAbstract:
Within the past few decades, commuter rail routes in several major metropolitan areas have been implemented to provide an alternative to automobile transportation. Urban planners in these cities are looking to commuter rail to mitigate congestion and pollution. However, research on the impacts of commuter rail development on the surrounding retail landscape is still needed. In metropolitan Dallas-Fort Worth, the Denton County Transportation Authority recently opened its new A-Train light rail service linking suburban Denton and downtown Dallas. This thesis examines urban changes that occurred in the years before and after the A-Train line's 2011 opening, with a focus on restaurant and retail development in the vicinity of the A-Train stations in Denton County. This analysis evaluates changes in retail density and type, the population surrounding stations, and municipal initiatives that shape the retail landscape of station vicinities. This was done by gathering field data, retailer listings, population data, and conducting interviews with local businesses and city planners. The findings suggest that A-train stations have had a differential impact on the surrounding landscape, depending on the existing retail landscape, the types of retailers present, and the current state of municipal infrastructure that promotes accessibility. Overall, results suggest that urban planners play a vital role in harnessing the potential of commuter rail to promote nearby retail growth.
38
Kheir, Nizar. "Response policies and counter-measure : management of service dependencies and intrusion and reaction impacts." Télécom Bretagne, 2010. http://www.theses.fr/2010TELB0162.
Full textAbstract:
Nowadays, intrusion response is challenged by both attack sophistication and the complexity of target systems. In fact, Internet currently provides an exceptional facility to share resources and exploits between novice and skilled attackers. As a matter of fact, simply detecting or locally responding against attacks has proven to be insufficient. On the other hand, in order to keep pace with the growing need for more interactive and dynamic services, information systems are getting increasingly dependent upon modular and interdependent service architectures. In consequence, intrusions and responses often have drastic effects as their impacts spread through service dependencies. We argue in this thesis that service dependencies have multiple security implications. In the context of intrusion response, service dependencies can be used to find the proper enforcement points which are capable to support a specific response strategy. They can be also used in order to compute the impact of such responses in order to select the least costly response. In a first attempt to realize the thesis objectives, we explore graph-based service dependency models. We implement intrusion and response impacts as security flows that propagate within a directed graph. We introduce countermeasures as transformations to the dependency graph, and which have direct implications on the impact flows triggered by an intrusion. In a second step, we replace the analytic graph-based approach with a simulation-based approach using colored Petri nets. We develop for this purpose a new service dependency model that outperforms the initial graph-based models. It represents access permissions that apply to service dependencies. Attacker permissions are also implemented in this model by interfacing with attack graphs. We develop a simulation platform that tracks the propagation of intrusion impacts, response impacts, and the combined impacts for intrusion and response. We define a new response index, the return on response investment (RORI), that we evaluate for each response candidate with the aim to select the one that provides a maximal positive RORI index.
39
Feng, Wei. "Analyses of Bus Travel Time Reliability and Transit Signal Priority at the Stop-To-Stop Segment Level." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1832.
Full textAbstract:
Transit travel time is affected by many factors including traffic signals and traffic condition. Transit agencies have implemented strategies such as transit signal priority (TSP) to reduce transit travel time and improve service reliability. However, due to the lack of empirical data, the joint impact of these factors and improvement strategies on bus travel time has not been studied at the stop-to-stop segment level.
This study utilizes and integrates three databases available along an urban arterial corridor in Portland, Oregon. Data sources include stop-level bus automatic vehicle location (AVL) and automatic passenger count (APC) data provided by the Tri-County Metropolitan Transportation District of Oregon (TriMet), the Sydney Coordinated Adaptive Traffic System (SCATS) signal phase log data, and intersection vehicle count data provided by the City of Portland. Based on the unique collection and integration of these fine granularity empirical data, this research utilizes multiple linear regression models to understand and quantify the joint impact of intersection signal delay, traffic conditions and bus stop location on bus travel time and its variability at stop-to-stop segments. Results indicate that intersection signal delay is the key factor that affects bus travel time variability. The amount of signal delay is nearly linearly associated with intersection red phase duration. Results show that the effect of traffic conditions (volumes) on bus travel time varies significantly by intersection and time of day.
This study also proposed new and useful performance measures for evaluating the effectiveness of TSP systems. Relationships between TSP requests (when buses are late) and TSP phases were studied by comparing TSP phase start and end times with bus arrival times at intersections. Results show that green extension phases were rarely used by buses that requested TSP and that most green extension phases were granted too late. Early green effectiveness (percent of effective early green phases) is much higher than green extension effectiveness. The estimated average bus and passenger time savings from an early green phase are also greater compared to the average time savings from a green extension phase. On average, the estimated delay for vehicles on the side street due to a TSP phase is less than the time saved for buses and automobiles on the major street.
Results from this study can be used to inform cities and transit agencies on how to improve transit operations. Developing appropriate strategies, such as adjusting bus stop consolidation near intersections and optimizing bus operating schedules according to intersection signal timing characteristics, can further reduce bus travel time delay and improve TSP effectiveness.
40
Sanyang, Edrisa. "Risk factors and injury characteristics among trauma patients in the Gambia." Diss., University of Iowa, 2016. https://ir.uiowa.edu/etd/2270.
Full textAbstract:
This research focuses on injuries from all mechanisms, with particular focus on road traffic injuries in urban Gambia. Data from trauma registries established in two major trauma hospitals were used to address three aims: 1) examine the general characteristics of injured individuals and their injuries, and identify factors associated with discharge status from the hospital emergency room; 2) identify differences in road-user, collision, vehicle, and driver factors, among individuals hospitalized with a road traffic injury; and 3) examine personal, crash, and injury factors associated with transfer status among road traffic injured (RTI) patients, and identify limitations of the current trauma systems that might be improved for more efficient use of resources.
Data used for this dissertation were from trauma registries established in two major trauma hospitals in The Gambia: Edward Francis Small Teaching Hospital (EFSTH) and Serrekunda General Hospital (SGH). At intake, the treating physicians and nurses completed an accident and emergency ward survey form for injuries from all mechanisms. For admitted road traffic injured patients (admission more than 24 hours), the road traffic injured admission form is completed. Data about risk factors contributing to crashes and injuries were collected from the patients. At hospital discharge, treating physicians used a 19-item questionnaire to collect data on the discharge status and disability at discharge of road traffic injured patients.
Using the trauma registry data from March 1, 2014 to March 31, 2016, we found the leading mechanism of injury was road traffic. For place of occurrence, injuries mostly occur at home and on the road. Assault was higher among young females (19 to 44 years) than males. Males have increased odds for admission and disability due to road traffic injuries. We also found that among admitted road traffic injured patients, injuries to pedestrians, bicyclists, and motorcyclists were higher than other road users. Crashes involved risk factors at person, crash, and environment levels. Head/skull injuries were common, and concussions/brain injuries were higher among pedestrians, bicyclists, and motorcyclists than vehicle occupants. Finally, our results also suggest that vehicle occupants, and professionals/skilled personnel had increased odds of being transferred than directly admitted RTI patients. Fractures/dislocations, and concussions/brain injuries were frequent among transfers. Intravenous fluid was the most frequent treatment administered to patients transferred to the definitive-care hospitals.
This project shows that injuries, especially road traffic, create a large burden of injury in The Gambia and the many contributing factors. It also provides evidence that there are many opportunities to intervene at personal, crash, and environment levels. Additionally, creating trauma registries across the country as well as trauma response system will have a greater impact to reduce burden of road traffic crashes in The Gambia.
41
Xia, Binyan. "How to Present Statistical Comparisons between Swedish Hospitals and Counties." Thesis, Uppsala universitet, Statistiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-154805.
Full textAbstract:
Background The Swedish Association of local authorities and regions in collaboration with the national board of health and welfare produces the yearly “Swedish Health Care Report” in order to provide evaluations of the hospitals and counties in Sweden for both the politicians and the general public. Method We describe several standard methods which have been used to present the performance of each hospital or county: Forest plot (FL), League Table (LT), League Plot (LP) and Funnel Plot (FP). Using simulation technique to produce the League Plot of rank is also presented in order to illustrate the unreliable of the ranking principle. Results The league plot with confidence interval is easily understood by people, but it should provide the total number of operations (sample size) as well. The resulting multiple-indicators system gives a clear overview of the whole system, but the cut-off points used in the traffic light method is not the best choice. Several possible improved methodologies are: A league plot traffic light method and a standard funnel plot traffic light method is recommended when aiming at finding the outliers; A p=0.67 funnel plot traffic light method is suggested when wishing to divide the units into approximately equally large groups; A one-side traffic light method seems to be a wonderful choice when focusing on the bad performance units.
42
Bennett, Katharine D. "Spatial Analysis of Motor Vehicle Accidents in Johnson City, Tennessee, as Reported to Washington County Emergency Communications District (911)." Digital Commons @ East Tennessee State University, 2010. https://dc.etsu.edu/etd/1778.
Full textAbstract:
This study spatially analyzes emergency 911 call-for-service records from January 1, 2000 through December 31, 2009 for motor vehicle accidents inside the corporate limits of Johnson City, Tennessee. Records were compared according to the land use classification for adjacent properties, roadway type, and traffic signal proximity. Data were evaluated through ArcGIS software using proximity analysis, point pattern analysis, and hotspot analysis.
Motor vehicle accidents evaluated during this study consist of accident locations reported to the Washington County Emergency Communications District concerning property damage, personal injury, and fatalities. Results indicate localized areas with the highest number of traffic accidents contain the most motor vehicle injury accidents. Twice as many motor vehicle accidents occur near commercial properties compared to residential properties. Motor vehicle accidents are more likely to occur on arterial thoroughfares. Approximately 40% of injury accidents happen at roadway intersections, with 22% occurring at signalized intersections.
43
Richard, Olivier. "Régulation court terme du trafic aérien et optimisation combinatoire : application de la méthode de génération de colonnes." Phd thesis, Grenoble INPG, 2007. http://tel.archives-ouvertes.fr/tel-00580414.
Full textAbstract:
Ce travail a pour objet la résolution d'un problème combinatoire posé dans le cadre de la régulation court terme (ou dynamique) du trafic aérien. On cherche à déterminer pour chaque vol régulable une trajectoire en 4 dimensions réalisable de manière à respecter les contraintes de capacité des secteurs tout en minimisant la somme des coûts des trajectoires choisies. Le problème est modélisé par un programme linéaire mixte. Une représentation ad hoc du système aérien sert de support à la modélisation fine des trajectoires. Un processus global de résolution basé sur la génération de colonnes couplée à la technique de branch-and-bound est détaillé. Les colonnes du problème représentant des trajectoires, la génération de colonnes par le sous problème de tarification se traduit par la recherche de chemins tridimensionnels sur un réseau continu et dynamique. Un algorithme spécifique basé sur les algorithmes de plus court chemin par marquage et sur la programmation dynamique est développé et testé. Toute la méthode est évaluée sur des instances réelles représentant l'espace aérien géré par la CFMU, l'organisme européen de gestion des flux de trafic aérien. Les résultats obtenus en un temps de calcul compatible avec le contexte opérationnel valident finalement la méthode
44
Abadie, Guillaume. "Étude du trafic cytonucléaire de la β-arrestine 2 par une approche génétique." Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCB083.
Full text
45
HOCEINI, SAID. "Techniques d'Apprentissage par Renforcement pour le Routage Adaptatif dans les Réseaux de Télécommunication à Trafic Irrégulie." Phd thesis, Université Paris XII Val de Marne, 2004. http://tel.archives-ouvertes.fr/tel-00010430.
Full textAbstract:
L'objectif de ce travail de thèse est de proposer des approches algorithmiques permettant de traiter la problématique du routage adaptatif (RA) dans un réseau de communication à trafic irrégulier. L'analyse des algorithmes existants nous a conduit à retenir comme base de travail l'algorithme Q-Routing (QR); celui-ci s'appuie sur la technique d'apprentissage par renforcement basée sur les modèles de Markov. L'efficacité de ce type de routage dépend fortement des informations sur la charge et la nature du trafic sur le réseau. Ces dernières doivent être à la fois, suffisantes, pertinentes et reflétant la charge réelle du réseau lors de la phase de prise de décision. Pour remédier aux inconvénients des techniques utilisant le QR, nous avons proposé deux algorithmes de RA. Le premier, appelé Q-Neural Routing, s'appuie sur un modèle neuronal stochastique pour estimer et mettre à jour les paramètres nécessaires au RA. Afin d'accélérer le temps de convergence, une deuxième approche est proposée : K-Shortest path Q-Routing. Elle est basée sur la technique de routage multi chemin combiné avec l'algorithme QR, l'espace d'exploration étant réduit aux k meilleurs chemins. Les deux algorithmes proposés sont validés et comparés aux approches traditionnelles en utilisant la plateforme de simulation OPNET, leur efficacité au niveau du RA est mise particulièrement en évidence. En effet, ceux-ci permettent une meilleure prise en compte de l'état du réseau contrairement aux approches classiques.
46
Shankar, Sanjeev. "Analysis of microprocessor based vehicular instrumentation and automatic passenger counting systems." Thesis, Virginia Tech, 1985. http://hdl.handle.net/10919/41570.
Full textAbstract:
Information on transit ridership and operations is a
necessary condition as far as efficient management is considered.
Transit managements on the acquisition of such a
data base can confirm predictions about scheduling, receive
warnings about potential dangers and plan future operations
on a much broader and precise base. Data from passenger counts provide essential information to marketing and scheduling
personnel by identifying peak load-points and the such.
Using manual collection methods for such data is expensive
and prone to human errors. Automatic Passenger Counting
(APC) systems are viewed as an improved and economical technique
for data collection. Such systems monitor the progress
of a particular vehicle -- its position, number of passengers
getting on and off, times and distances between stops -- and
make this data available for processing. These are state of
the art systems, mostly microprocessor based and often embracing
a modular structure. The Red Pine system is such a system with different dedicated modules for each bank of
tasks. Multitasking software is seen to be an powerful tool
for such systems and simplify the architecture of the system
hardware. A CHMOS hardware design, suited for multitasking
softwares is provided. Interfacing software for the Red Pine
system has been developed and is explained. Debugging testing
and simulation of the Red Pine hardware is detailed.
Modifications have been recorded and improvements suggested.Master of Science
47
Sears, Jill R. "Spatial Distribution of Nitrogen Oxides, Benzene, Toluene, Ethylbenzene, and Xylenes in Hillsborough County, Florida| An Investigation of Impacts of Urban Forests on Ambient Concentrations of Air Pollutants Associated with Traffic." Thesis, University of South Florida, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1548512.
Full textAbstract:
Urban air pollution is responsible for high levels of morbidity and mortality in exposed populations due to its effects on cardiovascular and respiratory function. Transportation-related air pollutants account for the majority of harmful air pollution in urban areas. Forests are known to reduce air pollution through their ability to facilitate dry deposition and atmospheric gas exchange. This work characterizes the interactions between transportation air pollutants and urban forests in Hillsborough County, Florida. A highly spatially resolved passive air sampling campaign was conducted to characterize local concentrations of nitrogen oxides, benzene, toluene, ethylbenzene, and xylenes (BTEX) in Hillsborough County, Florida. Sampling locations included a proportion of densely forested urban areas in order to determine the effects of Hillsborough County's urban forest resources on localized concentrations of selected transportation pollutants. Recommended approaches for the use of urban forests as an effective air pollution mitigation technique in Hillsborough County were generated based on results from the sampling campaign. Results show mean concentrations of 2.1 parts per billion and 6.5 µg/m3 for nitrogen oxides and total BTEX, respectively. High spatial variability in pollutant concentrations across Hillsborough County was observed, with the coefficient of variation found to be 0.61 for nitrogen oxides and 0.79 for total BTEX. Higher concentrations were observed along interstate highways, in urban areas of the county, and near select point sources in rural areas. Differences in concentrations within forested areas were observed, but were not statistically significant at the 95% confidence level. These results can be used to identify elements of urban design which contribute to differences in concentrations and exposures. This information can be used to create more sustainable urban designs which promote health and equity of the population.
48
Sears, Jill. "Spatial Distribution of Nitrogen Oxides, Benzene, Toluene, Ethylbenzene, and Xylenes in Hillsborough County, Florida: An Investigation of Impacts of Urban Forests on Ambient Concentrations of Air Pollutants Associated with Traffic." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4842.
Full textAbstract:
Urban air pollution is responsible for high levels of morbidity and mortality in exposed populations due to its effects on cardiovascular and respiratory function. Transportation-related air pollutants account for the majority of harmful air pollution in urban areas. Forests are known to reduce air pollution through their ability to facilitate dry deposition and atmospheric gas exchange. This work characterizes the interactions between transportation air pollutants and urban forests in Hillsborough County, Florida. A highly spatially resolved passive air sampling campaign was conducted to characterize local concentrations of nitrogen oxides, benzene, toluene, ethylbenzene, and xylenes (BTEX) in Hillsborough County, Florida. Sampling locations included a proportion of densely forested urban areas in order to determine the effects of Hillsborough County's urban forest resources on localized concentrations of selected transportation pollutants. Recommended approaches for the use of urban forests as an effective air pollution mitigation technique in Hillsborough County were generated based on results from the sampling campaign. Results show mean concentrations of 2.1 parts per billion and 6.5 µg/m3 for nitrogen oxides and total BTEX, respectively. High spatial variability in pollutant concentrations across Hillsborough County was observed, with the coefficient of variation found to be 0.61 for nitrogen oxides and 0.79 for total BTEX. Higher concentrations were observed along interstate highways, in urban areas of the county, and near select point sources in rural areas. Differences in concentrations within forested areas were observed, but were not statistically significant at the 95%#37; confidence level. These results can be used to identify elements of urban design which contribute to differences in concentrations and exposures. This information can be used to create more sustainable urban designs which promote health and equity of the population.
49
Dalqamouni, Ahmad Yousef. "Development of a Landslide Hazard Rating System for Selected Counties in Northeastern Ohio." Kent State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=kent1299284289.
Full text
50
Belarbi, Fahim. "Les systèmes de communication entre les véhicules et l'infrastructure : leur contribution aux pratiques d'exploitation de la route : Le cas d'une application pour l'information des autoroutes (AIDA)." Phd thesis, Ecole des Ponts ParisTech, 2004. http://pastel.archives-ouvertes.fr/pastel-00000955.
Full textAbstract:
L'exploitation de la route désigne l'ensemble des actions visant à rendre la circulation aussi sûre, fluide et confortable que possible. Ce domaine est aujourd'hui en pleine mutation grâce notamment aux progrès des nouvelles technologies de l'information et de la communication. Celles-ci ont favorisé l'émergence d'applications encore incertaines jusqu'à une date récente. Cette révolution technologique est en train de modifier les pratiques dans le domaine de l'exploitation routière. On assiste au développement accéléré des équipements embarqués et systèmes informatiques basés sur une communication entre la route et le véhicule. Ces nouveaux dispositifs sont-ils aptes à remplir des fonctions d'exploitation routière assurées aujourd'hui par des systèmes classiques ? Peuvent-ils constituer une alternative potentielle aux outils existants de recueil de données ? Cette thèse apporte des éléments de réponse à ces questions à travers l'exploration des potentialités des systèmes de communication entre la route et les véhicules à remplir des missions d'exploitation: maintien de la viabilité, gestion de trafic et aide au déplacement. Ces travaux tentent d'appréhender les apports d'un système de communication route - véhicule pour la sécurité et la gestion du trafic routier. Quels sont les enjeux économiques de ces dispositifs et quels en sont les principaux bénéficiaires ? L'étude d'un système déployé sur un tronçon autoroutier expérimental fournit des enseignements sur sa rentabilité économique pour la collectivité et financière pour le gestionnaire d'infrastructures. Les scénarios examinés permettent d'alimenter les réflexions sur des stratégies d'équipement en matière de nouveaux outils de recueil de données et de surveillance d'un réseau autoroutier.