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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.
1

Avaliação do potencial eólico em microescala de cascavel e região / Wind potential evaluation in microscale Cascavel and region

Sato, Mireille 09 March 2015 (has links)
Made available in DSpace on 2017-07-10T15:14:21Z (GMT). No. of bitstreams: 1 DissertacaoMireilleSato.pdf: 2602186 bytes, checksum: b65d61aed935a5e4bd3463d40d50e82e (MD5) Previous issue date: 2015-03-09 / The global energy scenario points to the need for alternative energy sources, given the dependence on finite fossil fuels and highly polluting. Among the clean energy resources, there is the wind, inexhaustible resource that gives the transformation of the kinetic energy contained in wind into mechanical energy through a turbine The global wind power available is around 53.000 TWh /year , since in terms of wind potential 143.000 MW fit the Brazilian wind potential and of this total 1.360 MW give the state of Paraná, locus of this study . Within this context , this study aims to determine the wind potential for microgeneration and minigeneration Cascavel and region, and has the following specific objectives determine the average speed of winds and annual seasonally each municipality target of this investigation, determining the annual wind potential of each target district this investigation depending on the heights of the tower 10 , 25 and 40 meters, analyzing the annual energy required by a residence and a water pump comparing it with the annual energy generated by the wind power system for all municipalities in question and the type of wind development more suitable for the use of wind power available for each target municipality of this investigation.The methodology is to develop histograms of wind speed in the municipalities of Assis Chateaubriand, Cascavel, Foz do Iguaçu, Guaíra, Palotina, Santa Helena, São Miguel do Iguaçu and Toledo , as well as describe the wind speed variable flow by Function Weibull probability density , determine the wind potential and finally achieve the required and generated energy simulation . At the end of the work can be concluded that only the city of Cascavel has a good wind potential . / O cenário energético mundial aponta para a necessidade de fontes alternativas de energia, haja vista a dependência de combustíveis fósseis finitos e altamente poluentes. Dentre os recursos energéticos limpos, tem-se a energia eólica, recurso inesgotável que se dá pela transformação da energia cinética contida nos ventos em energia mecânica por meio de um aerogerador. A energia eólica mundial disponível é da ordem de 53.000 TWh/ano, já em termos de potencial eólico 143.000 MW cabem ao potencial eólico brasileiro e deste total 1.360 MW conferem ao estado do Paraná, lócus deste estudo. Dentro deste contexto, o presente trabalho tem como objetivo principal determinar o potencial eólico para microgeração e minigeração de Cascavel e região, bem como tem por objetivos específicos determinar a velocidade média dos ventos anual e sazonalmente de cada município alvo desta investigação, determinar o potencial eólico anual de cada município alvo desta investigação em função das alturas da torre de 10, 25 e 40 metros, analisar a energia anual requerida por uma residência e de uma bomba de água comparando-a com a energia anual gerada pelo sistema eólico para todos os municípios em questão e indicar o tipo de empreendimento eólico mais adequado para o aproveitamento do potencial eólico disponível para cada município alvo da desta investigação. A metodologia consiste em elaborar histogramas de velocidade do vento dos municípios de Assis Chateubriand, Cascavel, Foz do Iguaçu, Guaíra, Palotina, Santa Helena, São Miguel do Iguaçu e Toledo, assim como descrever o fluxo variável de velocidade do vento por meio da Função Densidade de Probabilidade Weibull, determinar o potencial eólico e por fim realizar a simulação de energia requerida e gerada. Ao final do trabalho pode-se concluir que apenas o município de Cascavel tem um potencial eólico satisfatório.
2

Análise de padrões operacionais da frota de ônibus de transporte público no municí­pio de São Paulo e a influência de fatores climáticos em sua dinâmica. / Understanding temporal, weather and spatialvariation patterns in São Paulo urban bus travel speeds.

Gonçalves, Erick Sobreiro 04 December 2017 (has links)
Atualmente existem muitas fontes de dados oriundos de movimentação de pessoas e veículos. Deduzir o comportamento do tráfego a partir desses dados pode ser de grande utilidade para a gestão do tráfego. Entretanto, os métodos existentes podem não abordar todas as dimensões referentes ao comportamento do tráfego, em especial sob efeito de adversidades, como por exemplo - eventos climáticos. O objetivo dessa dissertação é apresentar uma combinação de métodos estatísticos e de análise espacial, para uso na compreensão dos padrões temporais e espaciais de variabilidade das velocidades, em condições normais e sob o impacto da precipitação. O método consiste na mineração de dados de micro trechos de deslocamento (microviagens), através da combinação de estatísticas descritivas, árvores de regressão CHAID (Chi square automatic interaction detection) e análises espaciais (Krigagem). Para a validação do método foram utilizados dados obtidos, durante março de 2014, de operação da frota de ônibus municipal da cidade de São Paulo, fornecidos pela São Paulo Transportes (SPTrans). Os dados de precipitação de chuva foram fornecidos pelo Instituto Nacional de Meteorologia (INMET). Os resultados demonstraram o impacto da precipitação sobre a variabilidade das velocidades por dia da semana e hora do dia. Adicionalmente, com base nos conjuntos de dados classificados via CHAID, foram produzidas representações da distribuição das velocidades sobre a superfície através uso da Krigagem. Observou-se uma consistente queda das velocidades no período vespertino, principalmente entre 16:00 e 19:00 horas, frequentemente agravados pela presença de precipitação. Foram selecionados casos de alta variabilidade, a partir da técnica CHAID, que foram analisados espacialmente. Os efeitos da queda da variabilidade foram observados geograficamente, demonstrando que a infraestrutura de transporte é um importante fator em sua caracterização. O estudo demonstra a viabilidade desta abordagem e a importância de incorporar a geografia no entendimento da variabilidade das velocidades em geral. / Nowadays there is a wide number of movement data sources which can be useful in transportation management. However, the existing methods may not cover all traffic dimensions, especially under inclement weather. The objective of this work is presenting a combination of statistical and spatial methods which allows to understand space and time speed patterns, considering regular operation conditions in comparison with rainfall events. The method consists in sequential bus tracking data segments (micro travel) mining by the combination of descriptive statistics, CHAID (Chi square automatic interaction detection) regression trees and spatial analysis (Kriging). To validate the method, São Paulo bus fleet tracking data provided by SPTrans, and rainfall precipitation, provided by INMET was combined and processed. The results presented rainfall as a relevant factor of speed variability by day of week and time of the day. A consistent speed decrease in the afternoon period, mainly between 4:00 PM and 7:00 PM, was observed. Such effects are more intense in face of rainfall precipitation. The highest variability cases obtained by CHAID classification was selected and spatially analyzed showing the transportation infrastructure is an important variability component. Such results show the importance of a geographic approach over speed variability.
3

Análise de padrões operacionais da frota de ônibus de transporte público no municí­pio de São Paulo e a influência de fatores climáticos em sua dinâmica. / Understanding temporal, weather and spatialvariation patterns in São Paulo urban bus travel speeds.

Erick Sobreiro Gonçalves 04 December 2017 (has links)
Atualmente existem muitas fontes de dados oriundos de movimentação de pessoas e veículos. Deduzir o comportamento do tráfego a partir desses dados pode ser de grande utilidade para a gestão do tráfego. Entretanto, os métodos existentes podem não abordar todas as dimensões referentes ao comportamento do tráfego, em especial sob efeito de adversidades, como por exemplo - eventos climáticos. O objetivo dessa dissertação é apresentar uma combinação de métodos estatísticos e de análise espacial, para uso na compreensão dos padrões temporais e espaciais de variabilidade das velocidades, em condições normais e sob o impacto da precipitação. O método consiste na mineração de dados de micro trechos de deslocamento (microviagens), através da combinação de estatísticas descritivas, árvores de regressão CHAID (Chi square automatic interaction detection) e análises espaciais (Krigagem). Para a validação do método foram utilizados dados obtidos, durante março de 2014, de operação da frota de ônibus municipal da cidade de São Paulo, fornecidos pela São Paulo Transportes (SPTrans). Os dados de precipitação de chuva foram fornecidos pelo Instituto Nacional de Meteorologia (INMET). Os resultados demonstraram o impacto da precipitação sobre a variabilidade das velocidades por dia da semana e hora do dia. Adicionalmente, com base nos conjuntos de dados classificados via CHAID, foram produzidas representações da distribuição das velocidades sobre a superfície através uso da Krigagem. Observou-se uma consistente queda das velocidades no período vespertino, principalmente entre 16:00 e 19:00 horas, frequentemente agravados pela presença de precipitação. Foram selecionados casos de alta variabilidade, a partir da técnica CHAID, que foram analisados espacialmente. Os efeitos da queda da variabilidade foram observados geograficamente, demonstrando que a infraestrutura de transporte é um importante fator em sua caracterização. O estudo demonstra a viabilidade desta abordagem e a importância de incorporar a geografia no entendimento da variabilidade das velocidades em geral. / Nowadays there is a wide number of movement data sources which can be useful in transportation management. However, the existing methods may not cover all traffic dimensions, especially under inclement weather. The objective of this work is presenting a combination of statistical and spatial methods which allows to understand space and time speed patterns, considering regular operation conditions in comparison with rainfall events. The method consists in sequential bus tracking data segments (micro travel) mining by the combination of descriptive statistics, CHAID (Chi square automatic interaction detection) regression trees and spatial analysis (Kriging). To validate the method, São Paulo bus fleet tracking data provided by SPTrans, and rainfall precipitation, provided by INMET was combined and processed. The results presented rainfall as a relevant factor of speed variability by day of week and time of the day. A consistent speed decrease in the afternoon period, mainly between 4:00 PM and 7:00 PM, was observed. Such effects are more intense in face of rainfall precipitation. The highest variability cases obtained by CHAID classification was selected and spatially analyzed showing the transportation infrastructure is an important variability component. Such results show the importance of a geographic approach over speed variability.
4

Analysis of traffic patterns for large scale outdoor events : A case study of Vasaloppet ski event

Ahmadi, Parisa January 2012 (has links)
Vasaloppet is a cross country ski event which has been held in Sweden for about 50 years. Now more than 50,000 people of different ages participate in various cross country ski races during the Vasaloppet winter week in Dalarna County. This increasing demand needs good traffic and transportation planning to avoid congestion and provide safe, on time and environmentally friendly transportation for participants and visitors to the area. The key for a good event traffic planning is reliable and up-to-date traffic data which is not available for the Vasaloppet winter week. This study is an attempt to collect traffic data in order to find the movement patterns in the area and estimate origin-destination matrices for the main event of Vasaloppet week. Based on resources and time limitation it was decided to use a web-base d participants’ survey in order to collect traffic data. The link to the survey was sent to email address of a sample of 5000 participants. About 64% of the participants drove from their home town to the area and about 31 percent travelled by bus. Train and airplane have a very small share in travel mode to the area. Malungsälen, Mora and Älvdalen are three municipalities in Dalarna County with the highest share in accommodating participants. On the day of the race, bus and car have approximately the same share in travel mode with 45% and 47% respectively.
5

Det avlastande bärsystemets påverkan på att bära en sjukbår : en studie baserad på prov och försök / The releiving carrying systems effect on stretcher carriage

Hallgren, Adam January 2021 (has links)
For a wounded soldier to have as good a chance of survival as possible, an important variable during care is the time it takes for the wounded to get to a high-quality medical facility where there is expertise in surgery. If the injured person is to be transported with a stretcher carried by other soldiers, the speed for which this can be done is limited by the strength of the bearer in the hands and forearms.This study aims to explore how the speed and perceived ergonomics of those who carry a stretcher can change for a group if it is issued a relieving carrying system that redistributes the load of the stretcher to the hips, back and legs. The study is largely based on a study by Knapik et al (2000) where similar tests were done in a controlled indoor environment but where this study was done in a field environment with groups of 2 or 4 people carrying a stretcher.The study is done in the form of tests and experiments with conscripts from Skaraborg Wing, F 7. The conscripts carried a stretcher in a field-like environment where speed, comfort and usability were in focus. The study was also done with a questionnaire belonging to the experiments to value the experience.The study resulted in a relieving carrying system integrated in the Swedish Armed Forces' combat vest 2000 having an increased average speed with the median 30.7% when carrying a stretcher loaded with 100 kg. The analysis shows that it is above all women who benefit greatly from not carrying a stretcher with their hands. Something they are statistically worse at than men. The study also shows that there are tendencies that the comfort is improved for a soldier. / För att en sårad soldat ska ha så goda chanser till överlevnad som möjligt är en viktig variabel under omhändertagandet tiden det tar för den sårade att komma till en högkvalitativ sjukvårdsinrättning, där det finns expertis inom kirurgi. Om den skadade ska transporteras med sjukbår som bärs av andra soldater, är hastigheten för vilket detta kan göras begränsad av de bärandes styrka i händer och underarmar.Denna studie syftar till att utforska hur hastigheten samt den upplevda ergonomin för de som bär en sjukbår kan förändras för en grupp om den tillförs ett avlastande bärsystem som omfördelar lasten till höfter, rygg och benen. Studien baseras till stor del på en studie av Knapik med flera (2000) där liknande tester gjordes i en kontrollerad inomhusmiljö, men där denna studie är gjord i en fältmiljö med grupper om 2 eller 4 personer som bär en sjukbår.Studien är gjord i form av prov och försök med värnpliktiga ur Skaraborgs Flygflottilj, F 7, som bär en bår i en fältliknande miljö där hastigheten, komforten och användbarheten stod i fokus. Studien är även gjord med en enkätundersökning tillhörande försöken i syfte att skatta upplevelsen.Studien resulterade i att ett avlastande bärsystem integrerat i Försvarsmaktens stridsväst 2000 medförde en ökad snitthastighet, med medianen 30,7%, vid bärande av en sjukbår 2 lastad med 100 kg. Analysen påvisar att det framför allt är kvinnor som har stor nytta av att inte bära en sjukbår med händerna, något de statistiskt sett är sämre på än män. Studien visar även att det finns tendenser för att komforten förbättras för en soldat men användbarheten är oförändrad.
6

Quantifying the Impact of Traffic-Related and Driver-Related Factors on Vehicle Fuel Consumption and Emissions

Ding, Yonglian 02 June 2000 (has links)
The transportation sector is the dominant source of U.S. fuel consumption and emissions. Specifically, highway travel accounts for nearly 75 percent of total transportation energy use and slightly more than 33 percent of national emissions of EPA's six Criteria pollutants. Enactment of the Clean Air Act Amendment of 1990 (CAAA) and the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) have changed the ways that most states and local governments deal with transportation problems. Transportation planning is geared to improve air quality as well as mobility. It is required that each transportation activity be analyzed in advance using the most recent mobile emission estimate model to ensure not to violate the Conformity Regulation. Several types of energy and emission models have been developed to capture the impact of a number of factors on vehicle fuel consumption and emissions. Specifically, the current state-of-practice in emission modeling (i.e. Mobile5 and EMFAC7) uses the average speed as a single explanatory variable. However, up to date there has not been a systematic attempt to quantify the impact of various travel and driver-related factors on vehicle fuel consumption and emissions. This thesis first systematically quantifies the impact of various travel-related and driver-related factors on vehicle fuel consumption and emissions. The analysis indicates that vehicle fuel consumption and emission rates increase considerably as the number of vehicle stops increases especially at high cruise speed. However, vehicle fuel consumption is more sensitive to the cruise speed level than to vehicle stops. The aggressiveness of a vehicle stop, which represents a vehicle's acceleration and deceleration level, does have an impact on vehicle fuel consumption and emissions. Specifically, the HC and CO emission rates are highly sensitive to the level of acceleration when compared to cruise speed in the range of 0 to 120 km/h. The impact of the deceleration level on all MOEs is relatively small. At high speeds the introduction of vehicle stops that involve extremely mild acceleration levels can actually reduce vehicle emission rates. Consequently, the thesis demonstrated that the use of average speed as a sole explanatory variable is inadequate for estimating vehicle fuel consumption and emissions, and the addition of speed variability as an explanatory variable results in better models. Second, the thesis identifies a number of critical variables as potential explanatory variables for estimating vehicle fuel consumption and emission rates. These explanatory variables include the average speed, the speed variance, the number of vehicle stops, the acceleration noise associated with positive acceleration and negative acceleration noise, the kinetic energy, and the power exerted. Statistical models are developed using these critical variables. The statistical models predict the vehicle fuel consumption rate and emission rates of HC, CO, and NOx (per unit of distance) within an accuracy of 88%-96% when compared to instantaneous microscopic models (Ahn and Rakha, 1999), and predict emission rates of HC, CO, and NOx within 95 percentile confidence limits of chassis dynamometer tests conducted by EPA. Comparing with the current state-of-practice, the proposed statistical models provide better estimates for vehicle fuel consumption and emissions because speed variances about the average speed along a trip are considered in these models. On the other hand, the statistical models only require several aggregate trip variables as input while generating reasonable estimates that are consistent with microscopic model estimates. Therefore, these models could be used with transportation planning models for conformity analysis. / Master of Science
7

Vztah morfometrických charakteristik terénu a síťových analýz v prostředí GIS / Relationship between morphometric characteristics of the terrain and network analysis in GIS

Kufner, Jan January 2013 (has links)
The main objective of the diploma thesis is creation of methodology and automatization of calibration process of network graph based on the values of morphometric characteristics and motion vectors. The resulting morphometric values of the terrain have been detected on the basis of mathematical and cartographic methods for line course expression. The most accurate one has been used in GIS network analysis over the road network and digital terrain models, which were chosen as the most appropriate for this purpose. Relationship between morphometric values and values suitable for use in network analysis (speed, time, ...) has been studied using specific examples in appropriately selected territory with using selected vehicle, which was designated as a bicycle. The practical part for the verification of functionality of the suggested methodology has been compared with other models of accessibility, available web-map portals and route planners. The process of transport network evaluation based on selected parameters has been automated in Python programming language as a tool in ArcGIS software, which is attached to the diploma thesis. Powered by TCPDF (www.tcpdf.org)
8

Lançamento oblíquo: uma abordagem matemática / Oblique launch: a mathematical approach

Almeida, Francisco Fabio Monteiro de 31 March 2016 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-03T14:04:36Z No. of bitstreams: 2 Dissertação - Francisco Fabio Monteiro de Ameida - 2016.pdf: 1329167 bytes, checksum: 102bfaddf62d4fafa436b4f868337d0d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-03T14:08:11Z (GMT) No. of bitstreams: 2 Dissertação - Francisco Fabio Monteiro de Ameida - 2016.pdf: 1329167 bytes, checksum: 102bfaddf62d4fafa436b4f868337d0d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-03T14:08:11Z (GMT). No. of bitstreams: 2 Dissertação - Francisco Fabio Monteiro de Ameida - 2016.pdf: 1329167 bytes, checksum: 102bfaddf62d4fafa436b4f868337d0d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-03-31 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The main goal of this work is to verify that we can assign the oblique launch a mathematical approach. To reach this conclusion, we address important issues of mathematics and physics, as linear functions and quadratic functions , and uniform and uniformly varied movements. These concepts were presented to facilitate understanding and implement an equation that allows to determine the moment of rise, the maximum height and horizontal reach, knowing an shot's angle, the initial velocity and gravity's acceleration. / O objetivo principal desse trabalho é veri car que podemos atribuir ao lançamento oblíquo uma abordagem matemática. Para chegarmos a esta conclusão, abordamos assuntos importantes da Matemática e da Física, como funções a m e quadrática, e movimentos uniforme e uniformemente variado. Tais conceitos foram apresentados para facilitar o entendimento e implementar uma equação que permita determinar o instante de subida, a altura máxima e o alcance horizontal, conhecendo um ângulo de tiro, a velocidade inicial e a aceleração da gravidade.
9

Empirical Essays on Transport and Regional Economics: Safety, Intermodality, and Commuting Dynamics

Borsati, Mattia 25 June 2020 (has links)
The following doctoral thesis, sponsored by Autostrada del Brennero S.p.A. (an Italian highway concession company in charge of managing toll roads) consists on empirical essays at the crossroad between transport and regional economics. They focus on different aspects that directly involve motorways (i.e, safety, intermodality, and commuting dynamics) and they are aimed at providing further evidences that transport institutions and policy makers could take into account throughout their decision-making processes. The first chapter presents a research article that seeks to determine the impact of an average speed enforcement system in reducing highway accidents. Indeed, at the end of 2005, Autostrade per l'Italia (ASPI) and the Italian traffic police progressively deployed along the Italian tolled motorway network an average speed enforcement system, named Safety Tutor, able to determine the average speed of vehicles over a long section to encourage drivers to comply with speed limits and improve safety. To empirically test the extent to which Safety Tutor led to a reduction in both total and fatal accidents on Italian highways during the period of 2001-2017, we carried out a generalized difference-in-differences estimation using a unique panel dataset that exploits the heterogeneous accident data within all tolled motorway sectors in a quasi-experimental setting. To deal with the potential endogeneity of the non-random placement of Safety Tutor sites, we utilized an instrumental variable strategy by using the network of motorway sectors managed by ASPI and its controlled concessionaires from 2005 onwards (i.e., when the technology was available) as an instrument to predict Safety Tutor adoption. We found that a 10% increase in Safety Tutor coverage led to an average reduction in total accidents of 3.9%, whereas there is no evidence of a significant causal effect of Safety Tutor in reducing fatal accidents. The second chapter presents a research article that seeks to investigate the inter-modal competition between motorway and high-speed rail (HSR) services, as the extent to which HSR demand could be the result of a modal shift from motorways is a relevant issue in any cost-benefit analysis of HSR investments. Indeed, the development of HSR has had a notable impact on modal market shares on the routes on which its services have been implemented. To analyse whether the HSR expansion in Italy has led to a modal shift from motorway to HSR, we empirically test i) whether HSR openings adjacent to motorway sectors have reduced the total km travelled by light vehicles on these sectors during the period 2001-2017; and ii) whether this reduction has been persistent or even more evident after the opening of on-track competition between two HSR operators. To do so, we carried out a generalized difference-in-differences estimation, using a unique panel dataset that exploits the heterogeneous traffic data within all tolled motorway sectors in a quasi-experimental setting. Our findings reveal that neither HSR openings nor the opening of on-track competition led to a modal shift from motorway to HSR services, as the two transport modes are non-competing. Conversely, HSR expansion had a slightly positive impact on motorway traffic. The third chapter presents a data article in a “data in brief” format that describes a dataset on municipality-to-municipality commuting patterns in Italy over the 1991, 2001, and 2011 censuses aimed at investigating the role of transport infrastructures and the structural transformation of the economy on worker mobility. At this purpose, a core origin-destination dataset on the number of workers moving between municipalities, or within the same municipality, has been linked with further municipality covariates on jobs location, population, and the distances in meters and journey times in minutes between all municipalities. Even though these data are freely available online, they require some tedious work to organize. Therefore, this data article brings the necessary information together and makes the dataset available on request. The dataset offers applied researchers an alternative source of information to shed new lights on the changing shape of urban systems by analysing i) the impact of infrastructural endowment in providing better job accessibility, or ii) the connection between increasing commuting patterns and the structural transformation of the economy due to the tertiarization process from 1991 to 2011.

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