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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

SPECIES DISTRIBUTION MODELING OF AMERICAN BEECH (FAGUS GRANDIFOLIA EHRH.) DISTRIBUTION IN SOUTHWESTERN OHIO

Flessner, Brandon P. 05 May 2014 (has links)
No description available.
52

How effective will a BRT system going to be in Santiago de Chile? Case studies

Ramirez-Bernal, Maria Fernanda 23 April 2008 (has links)
No description available.
53

Bus rapid transit (BRT) and transitoriented development (TOD) : How to transform and adjust the Swedish cities for attractive bus systems like BRT? What demands BRT?

Stojanovski, Todor January 2013 (has links)
Bus rapid transit (BRT) is an innovative bus system with sophisticated vehicles and inflexible busways integrated in the cities, high capacity and high quality, high speed and frequency, distinctive image and comfort. Many in Sweden believe that is impossible to introduce BRT, even though the Swedish towns and cities can benefit from the image, speed and frequency that BRT symbolizes. The archipelago-like urbanization, urban sprawl and the uncompetitive journey times of public transportation compared with the private car are identified as main obstacles. New questions emerged: Is it possible to transform and adjust the Swedish towns and cities for BRT? What demands BRT? How is transit-oriented development (TOD) applicable in a Swedish context as a policy to integrate cities and BRT? In this licentiate thesis I investigate the interrelationship between bus transportation and neighborhoods, between BRT and urban form as well as the possibilities to introduce busways and BRT, to trigger TOD and to transform the Swedish towns and cities for BRT. Much has been written about BRT, but seldom by architects or urban planners and designers. BRT and TOD are seen though urban form and processes of urbanization within a morphological tradition established by Kevin Lynch. BRT is represented by paths and nodes that disperse distinctive attractiveness pattern of desirability cores that shape neighborhoods as districts. TOD is about synchronizing the everyday urban life with public transportation systems. BRT-TOD is defined as a policy to recognize desirability cores spread by the different infrastructures of BRT and promote development of urban form within their attractiveness pattern at urban and regional scale. BRT-TOD is discussed as a concept of BRT metropolis in context of the urbanization of Swedish towns and cities.  TOD is defined morphologically as public transport cities. A public transport city is a city that in its development adapted to specific public transportation systems. TOD is nothing new in Europe or Sweden. To find regularities of the effect of public transportation systems on cities I do a historical overview of the Swedish towns and cities. In the end the position of bus and BRT, public transport cities and TOD and possibilities of future urban transformation of the smaller and larger Swedish cities towards BRT metropolises are discussed in context of today’s “‘system’ of automobility” and widespread car society and the emerging knowledge society and its postmodern fringes of urbanization. / <p>QC 20130917</p>
54

Potential Transportation Improvements and Land Use Impacts in the Elysian Fields Corridor

Lanford, Caroline 15 December 2007 (has links)
This study examines potential transportation improvements in the Elysian Fields Avenue Corridor, and the benefit that these improvements may produce. Data for the study area are compiled and analyzed. Conceptual plans for the implementation of different transit technology alternatives were developed and assessed in terms of user benefits, cost, potential land use impacts, potential economic impacts, and feasibility. Case studies and relevant literature are reviewed. The intent of this thesis is to provide an overview of the study area prior and subsequent to Hurricane Katrina, develop plans for the implementation of transit alternatives in the Elysian Fields Avenue Corridor, and assess potential costs and benefits of the different alternatives developed.
55

A real-time bus dispatching policy to minimize headway variance

Berrebi, Simon Jonas Youna 22 May 2014 (has links)
Transit agencies include buffer time in their schedules to maintain stable headways and avoid bus bunching. In this work, a real-time holding mechanism is proposed to dispatch buses on a loop-shaped route, solely based on operating conditions in real-time. Holds are applied at the terminal station to minimize the expected variance of bus headways at departure. The bus-dispatching problem is formulated as a stochastic decision process. The optimality equations are derived and structural properties of the optimal policy are inferred by backward induction. The exact optimal holding policy is then found in closed form, as a function of the expected travel time of buses currently running. A simulation assuming stochastic operating conditions and unstable headway dynamics is performed to assess the expected average waiting time of passengers at stations. The proposed control strategy is found to provide lower passenger waiting time and better resiliency than methods recommended in the literature and used in practice.
56

Transporte público y entorno construido: análisis de las áreas de influencia de las estaciones del BRT en la ciudad de Quito

Núñez Basantes, Alba Cristina 04 March 2024 (has links)
[ES] Los sistemas de buses de tránsito rápido (Bus Rapid Transit, BRT por sus siglas en inglés) han experimentado un gran crecimiento en los últimos años, pues más de 170 ciudades tienen algún tipo de sistema BRT. La evidencia empírica acerca de la relación entre el entorno urbano y estos sistemas todavía requiere ser estudiada, especialmente en las urbes en desarrollo que no disponen de información a pie de calle para realizar análisis en el nivel de las estaciones. En este contexto, el primer objetivo de la investigación fue generar datos a microescala (a pie de calle) del entorno próximo a las estaciones del sistema BRT de Quito, mediante métodos e instrumentos de análisis de campo, así como seguimientos, recopilación técnica de información de características del entorno urbano y encuestas. Además, se propuso utilizar los sistemas de información geográfica (SIG) para el manejo y análisis de los datos. Así, se obtuvieron mapas que representan la densidad de la población a escala de manzana y a escala de segmentos: la densidad de la edificación, la mezcla de usos de suelo (servicios, entidades públicas, escuelas, comercio, etc.); mezcla vertical (es decir, usos de vivienda, comercio y oficina en el mismo edificio) y características de espacio público (seguridad vial, ancho de acera, topografía, etc.). Se propuso también identificar el umbral de distancia máxima mediante el método de seguimiento, cuyo hallazgo revela que este umbral se sitúa en una distancia de 600 metros En relación al objetivo de analizar las características de los usuarios del sistema BRT y el comportamiento del viaje a través de una encuesta de intercepción, los resultados establecen que la mayoría de los usuarios encuestados corresponden al grupo femenino con formación académica universitaria que utiliza el transporte por trabajo. El siguiente objetivo fue determinar de forma cuantitativa la relación entre el sistema BRT de Quito y las características del entorno urbano en un umbral de distancia de 600 m, en 42 puntos a través del análisis estadístico multivariante (modelo de regresión múltiple). Los resultados señalan que la densidad de los segmentos del viario con acera entre 3 y 4 metros, la densidad del equipamiento de administración pública son variables significativas y positivas. Asimismo, la distancia al centro de la ciudad (accesibilidad regional) y la distancia a los destinos dentro de los 400 metros, (accesibilidad local), son dominios con signo negativo. Mientras que, la densidad no tiene un poder explicativo en el modelo de demanda del sistema tipo BRT de la ciudad de Quito. Asimismo, se planteó el examinar las cualidades del contexto inmediato de las mismas 42 estaciones del sistema BRT de Quito dentro de un umbral de distancia de 600 m a través del análisis estadístico multivariante. Los resultados muestran que la accesibilidad local, es decir, la distancia a la parada destino, el índice de rodeo (relación entre la distancia a pie medida a través de la red y la distancia euclidiana), el logaritmo de la densidad de la población se correlaciona de manera positiva con la distancia a pie. Mientras que, la densidad de los estratos (medio alto y alto), la densidad no residente (personas que trabajan, estudian o realizan otras actividades) y la distancia a la parada destino son variables significativas y con signo negativo. Otro objetivo de estudio fue tipificar el entorno urbano próximo de las 42 paradas en un umbral de distancia de 600 metros del sistema BRT de Quito a través del análisis estadístico factorial y los clústeres. Las características del entorno se clasificaron en tres factores. / [CA] Els sistemes de busos de trànsit ràpid (Bus Rapid Transit, BRT per les seues sigles en anglés) han experimentat un gran creixement en els últims anys, perquè més de 170 ciutats tenen algun tipus de sistema BRT. L'evidència empírica sobre la relació entre l'entorn urbà i estos sistemes encara requereix ser estudiada, especialment en les urbs en desenvolupament que no disposen d'informació a peu de carrer per a realitzar anàlisi en el nivell de les estacions. En este context, el primer objectiu de la investigació va ser generar dades a microescala (a peu de carrer) de l'entorn pròxim a les estacions del sistema BRT de Quito, mitjançant mètodes i instruments d'anàlisis de camp, així com seguiments, recopilació tècnica d'informació de característiques de l'entorn urbà i enquestes. A més, es va proposar utilitzar els sistemes d'informació geogràfica (*SIG) per al maneig i anàlisi de les dades. Així, es van obtindre mapes que representen la densitat de la població a escala de poma i a escala de segments: la densitat de l'edificació, la mescla d'usos de sòl (serveis, entitats públiques, escoles, comerç, etc.); mescla vertical (és a dir, usos d'habitatge, comerç i oficina en el mateix edifici) i característiques d'espai públic (seguretat viària, ample de vorera, topografia, etc.). Es va proposar també identificar el llindar de distància màxima mitjançant el mètode de seguiment, la troballa del qual revela que este llindar se situa en una distància de 600 metres En relació a l'objectiu d'analitzar les característiques dels usuaris del sistema BRT i el comportament del viatge a través d'una enquesta d'intercepció, els resultats estableixen que la majoria dels usuaris enquestats corresponen al grup femení amb formació acadèmica universitària que utilitza el transport per treball. El següent objectiu va ser determinar de manera quantitativa la relació entre el sistema BRT de Quito i les característiques de l'entorn urbà en un llindar de distància de 600 metres, en 42 punts a través de l'anàlisi estadística multivariant (model de regressió múltiple). Els resultats assenyalen que la densitat dels segments del viari amb vorera entre 3 i 4 metres, la densitat de l'equipament d'administració pública són variables significatives i positives. Així mateix, la distància al centre de la ciutat (accessibilitat regional) i la distància als destins dins dels 400 metres, (accessibilitat local), són dominis amb signe negatiu. Mentre que, la densitat no té un poder explicatiu en el model de demanda del sistema tipus BRT de la ciutat de Quito. Així mateix, es va plantejar l'examinar les qualitats del context immediat de les mateixes 42 estacions del sistema BRT de Quito dins d'un llindar de distància de 600 metres a través de l'anàlisi estadística multivariant. Els resultats mostren que l'accessibilitat local, és a dir, la distància a la parada destine, l'índex de marrada (relació entre la distància a peu mesurada a través de la xarxa i la distància euclidiana), el logaritme de la densitat de la població es correlaciona de manera positiva amb la distància a peu. Mentre que, la densitat dels estrats (mig alt i alt), la densitat no resident (persones que treballen, estudien o realitzen altres activitats) i la distància a la parada destine són variables significatives i amb signe negatiu. Un altre objectiu d'estudi va ser tipificar l'entorn urbà pròxim de les 42 parades en un llindar de distància de 600 metres del sistema BRT de Quito a través de l'anàlisi estadística factorial i els clústers. Les característiques de l'entorn es van classificar en tres factors. / [EN] Bus Rapid Transit (BRT) systems have experienced tremendous growth in recent years, with more than 170 cities having some form of BRT system. Empirical evidence about the relationship between the urban environment and these systems still needs to be studied, especially in developing cities that do not have street-level information for station-level analysis. In this context, the first objective of the research was to generate micro-scale data (at street level) of the environment near the stations of Quito's BRT system, through field analysis methods and tools, as well as monitoring, technical collection of information on urban environment characteristics and surveys. In addition, the use of geographic information systems (GIS) was proposed for data management and analysis. As a result, maps were obtained that represent population density at the block scale and at the segment scale: building density, mix of land uses (services, public entities, schools, commerce, etc.), vertical mix (i.e., housing, commerce and office uses in the same building) and public space characteristics (road safety, sidewalk width, topography, etc.). Also, it was proposed to identify the maximum distance threshold using the tracking method, the finding of which reveals a distance of 600 meters. Regarding the objective of recognizing the qualities of the users of the BRT system and the characteristics of the trip through the application of an intercept survey, the results establish that most of the surveyed users correspond to female group with university education who use the transport for work. The next objective was to quantitatively determine the relationship between Quito's BRT system and the characteristics of the urban environment at a distance threshold of 600 meters, at 42 locations through multivariate statistical analysis (multiple regression model). The results indicate that the density of road segments with sidewalks between 3 and 4 meters, the density of public administration equipment are significant and positive variables, likewise, the distance to the city center, regional accessibility and the distance to destinations within 400 meters, local accessibility, are domains with a negative sign. Meanwhile, density has no explanatory power in the demand model of the BRT type system in the city of Quito. Likewise, it was proposed to examine the qualities of the immediate context of the same 42 stations of the Quito BRT system within a distance threshold of 600 meters through multivariate statistical analysis. The results show that local accessibility, meaning the distance to the destination stop, the rounding index (ratio between the walking distance measured through the network and the Euclidean distance), the logarithm of the population density correlates positively with the walking distance. While, stratum density (upper middle and high), non-resident density (people working, studying or performing other activities) and distance to the destination stop are significant variables and with negative sign. Another study objective was to typify the proximate urban environment of the 42 stops within a distance threshold of 600 meters of the Quito BRT system through statistical factor analysis and clustering. The characteristics of the environment were classified into three factors. / Núñez Basantes, AC. (2024). Transporte público y entorno construido: análisis de las áreas de influencia de las estaciones del BRT en la ciudad de Quito [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/202963
57

Manliga vårdnadshavares användning av barnriktat tal i kommunikationen med sina små barn : En explorativ pilotstudie med material insamlat från videoinspelning och Language ENvironment Analysis (LENA)

Karlström, Sofie, Svensson, Sofie January 2022 (has links)
En stor del av den tidiga språkutvecklingen sker i samspel med vuxna, och kommunikationen mellan vårdnadshavare och deras små barn är därför särskilt betydelsefull. Vuxna anpassar ofta sitt sätt att tala till små barn genom att göra anpassningar i de språkliga parametrarna prosodi, segmentell fonologi, syntax, pragmatik och ordförråd. Dessa anpassningar kallas ofta för barnriktat tal (BRT) och har visat sig ha både en kortsiktig såväl som långsiktig positiv inverkan på barns tidiga språkutveckling. Tidigare forskning gällande barns tal- och språkmiljö har främst fokuserat på kommunikationen mellan kvinnliga vårdnadshavare och deras små barn. Det finns därmed ett behov av forskning som undersöker manliga vårdnadshavares kommunikation, särskilt med fokus på kvalitativa aspekter så som användandet av BRT. Inom Ord gör skillnad-projektet på KI utvecklas en ny interventionsmetod, Preventive Education Program for Parents (PEPP). I metoden kartläggs kvantitativa och kvalitativa aspekter av barns tal- och språkmiljö med hjälp av Language ENvironment Analysis (LENA), videoinspelning och ett framtaget PEPP-protokoll. I föreliggande studie undersöktes förekomsten av de parametrar som utgör BRT i manliga vårdnadshavares kommunikation med sina små barn. Mer specifikt undersöktes förekomst eller icke förekomst av parametrarna samt mest respektive minst förekommande parameter. Studien syftade även till att undersöka om PEPP-protokollets nuvarande beskrivningar av parametrarna kan användas för att bedöma förekomst av BRT. I studien deltog 6 manliga vårdnadshavare och deras barn i åldrarna 0 till 12 månader. Material från barnens tal- och språkmiljö samlades in med videoinspelning under en strukturerad leksituation och med LENA under en heldag i hemmiljö. Användandet av BRT analyserades både med hjälp av PEPP-metodens bedömningsprotokoll samt genom en kompletterande uppskattning av mest respektive minst förekommande parameter. Resultaten visade att 5 av 5 parametrar som utgör BRT förekom i samtliga deltagares kommunikation i hemmiljön samt i majoriteten av deltagarnas kommunikation under den strukturerade leksituationen. För hälften av deltagarna noterades parametern pragmatik som mest förekommande parameter och segmentell fonologi som minst förekommande parameter. I studien påtalas brister gällande PEPP-protokollets beskrivningar av parametrarna och författarna presenterar förslag på förbättringsåtgärder. / A large part of early language development takes place in interaction with adults, and the communication between caregivers and their young children is therefore particularly important for the child’s language development. Adults often adapt their way of speaking to young children by making adjustments in the linguistic parameters’ prosody, segmental phonology, syntax, pragmatics and vocabulary. These adaptations are often referred to as child-directed speech (CDS) and have been shown to have both adirect, as well as long-term positive impact on young children's language development. Previous research on children's speech and language environment has mainly focused on communication between female caregivers and their young children. Therefore, there is a need for research that examines male caregivers’ communication, especially with focus on qualitative aspects such as the use of CDS. Within the Words make a difference project at Karolinska Institutet (KI), researchers are developing a new intervention method, Preventive Education Program for Parents (PEPP). The method maps quantitative and qualitative aspects of children's speech and language environment using Language ENvironment Analysis (LENA), video recordings and a protocol developed within PEPP. The present study explored the occurrence of the parameters that constitute CDS in male caregivers' communication with their young children. More specifically, the occurrence or non-occurrence of the parameters as well as the most and least occurring parameter were examined. The study also aimed to investigate whether the PEPP protocol's current descriptions of the parameters could be used to assess the occurrence of CDS. The study involved 6 male caregivers and their children aged 0 to 12 months. Data from the children's speech and language environment were collected with a short video recording during a structured play situation, and with LENA from a daylong recording in the child’s natural home setting. The use of CDS was analyzed both by using the PEPP protocol, and well as by a supplementary estimation of the most and least occurring parameter. The results showed that 5 out of 5 parameters that constitute CDS occurred in all participants' communication in the natural home setting as well as in the majority of the participants' communication during the structured play situation. For half of the participants, pragmatics was noted as the most occurring parameter, and segmental phonology as the least occurring parameter. The current study highlights shortcomings regarding the PEPP protocol's descriptions of the parameters and the authors proposes suggestions for improvement of the PEPP method.
58

Assessing the potential of fuel saving and emissions reduction of the bus rapid transit system in Curitiba, Brazil

Dreier, Dennis January 2015 (has links)
The transport sector contributes significantly to global energy use and emissions due to its traditional dependency on fossil fuels. Climate change, security of energy supply and increasing mobility demand is mobilising governments around the challenges of sustainable transport. Immediate opportunities to reduce emissions exist through the adoption of new bus technologies, e.g. advanced powertrains. This thesis analysed energy use and carbon dioxide (CO2) emissions of conventional, hybrid-electric, and plug-in hybrid-electric city buses including two-axle, articulated, and biarticulated chassis types (A total of 6 bus types) for the operation phase (Tank-to-Wheel) in Curitiba, Brazil. The systems analysis tool – Advanced Vehicle Simulator (ADVISOR) and a carbon balance method were applied. Seven bus routes and six operation times for each (i.e. 42 driving cycles) are considered based on real-world data. The results show that hybrid-electric and plug-in hybrid-electric two-axle city buses consume 30% and 58% less energy per distance (MJ/km) compared to a conventional two-axle city bus (i.e. 17.46 MJ/km). Additionally, the energy use per passenger-distance (MJ/pkm) of a conventional biarticulated city bus amounts to 0.22 MJ/pkm, which is 41% and 24% lower compared to conventional and hybrid-electric two-axle city buses, respectively. This is mainly due to the former’s large passenger carrying capacity. Large passenger carrying capacities can reduce energy use (MJ/pkm) if the occupancy rate of the city bus is sufficient high. Bus routes with fewer stops decrease energy use by 10-26% depending on the city bus, because of reductions in losses from acceleration and braking. The CO2 emissions are linearly proportional to the estimated energy use following from the carbon balance method, e.g. CO2 emissions for a conventional two-axle city bus amount to 1299 g/km. Further results show that energy use of city bus operation depends on the operation time due to different traffic conditions and driving cycle characteristics. An additional analysis shows that energy use estimations can vary strongly between considered driving cycles from real-world data. The study concludes that advanced powertrains with electric drive capabilities, large passenger carrying capacities and bus routes with a fewer number of bus stops are beneficial in terms of reducing energy use and CO2 emissions of city bus operation in Curitiba.

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