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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.
231

Estudo da Infecção pelo Vírus da Hepatite B (HBV) em Caminhoneiros de Rota Longa do Brasil: Soroepidemiologia e Genótipos / Study of the Hepatitis B Virus Infection (HBV) in Long Distance Trucks Drivers in Brazil : Seroepidemiology and Genotypes

MATOS, Marcos André de 20 December 2008 (has links)
Made available in DSpace on 2014-07-29T15:04:27Z (GMT). No. of bitstreams: 1 dissertacao-marcos-andre-matos.pdf: 725697 bytes, checksum: e2fcb1b4531591c5a4eeebc3b47ca54f (MD5) Previous issue date: 2008-12-20 / The aim of this study was to investigate the seroepidemiological and molecular profile of the hepatitis B virus (HBV) infection in long distance truck drivers in Brazil. From October 2005 to 2006, 641 individuals were interviewed on sociodemographic and risk factors, and blood samples were collected to test for HBV markers (HBsAg, anti- HBs and anti-HBc) by the enzyme linked immunosorbent assay (ELISA). HBsAg positive samples were submitted to HBV DNA detection by polymerase chain reaction (PCR) and genotyping by restriction fragment length polymorphism (RFLP) analysis. A global prevalence of HBV was 18.9% (95% CI: 15.9-22.2): 16 were HBsAg positive, 117 anti-HBc total and 69 anti-HBs. Thirty truck drivers were anti- HBs only, suggesting vaccination against hepatitis B. Length of profession above 20 years, time away from home more than 15 days and history of sexually transmitted diseases (STD) were independently associated to HBV positivity by multivariate analysis. Among HBsAg-positive truck drivers, one (6.2%) were HBeAg reactive, nine (56.25%) anti-HBe positive and the rest negative for both markers. HBV DNA was detected in nine samples of the HBsAg-positive individuals, being identified the genotype A (22.2%), D (55.6%) and F (22.2%). These findings ratify the high risk of hepatitis B infection in truck drivers, and highlight the importance of public health politics addressed to this group whom presents characteristics which may favour HBV acquiring and it dissemination. / O objetivo deste estudo foi investigar o perfil soroepidemiológico e molecular da infecção pelo vírus da hepatite B em caminhoneiros de rota longa no Brasil. De outubro de 2005 a outubro de 2006, 641 indivíduos foram entrevistados sobre dados sócio-demográficos e fatores de risco, e coletadas amostras sanguíneas para detecção dos marcadores sorológicos do HBV (HBsAg, anti-HBs e anti-HBc) pelo ensaio imunoenzimático (ELISA). As amostras HBsAg reagentes foram submetidas a detecção do DNA viral pela reação da polimerase em cadeia (PCR) e genotipadas pela análise do polimorfismo de comprimento dos fragmentos de restrição (RFLP). A prevalência global para os marcadores da infecção pelo HBV foi de 18,9% (IC 95%: 15,9-22,2): 16 eram HBsAg positivos, 117 anti-HBc total e 69 anti-HBs. Trinta caminhoneiros apresentaram positividade isolada ao anti-HBs, evidenciando imunidade contra hepatite B. Tempo de profissão acima de 20 anos, tempo de permanência fora do lar superior a 15 dias e história de doença sexualmente transmissível (DST) foram fatores independentemente associados à positividade ao HBV pela análise multivariada. Dentre os caminhoneiros HBsAg reagentes, um (6,2%) apresentou reatividade ao HBeAg, nove (56,2%) ao anti-HBe e o restante negativo para ambos os marcadores. HBV DNA foi detectado em nove amostras de indivíduos HBsAg reagentes, sendo identificados os genótipos A (22,2%), D (55,6%) e F (22,2%). Os resultados deste estudo ratificam o risco elevado da população caminhoneira para infecção pelo HBV, e apontam para a necessidade de políticas públicas de saúde voltadas para este grupo, que apresenta características que favorecem a aquisição e disseminação do vírus da hepatite B.
232

Análise de anfetamina, cocaína e tetrahidrocanabinol em fluido oral de motoristas de caminhão que trafegam em rodovias do estado de São Paulo / Analysis of amphetamine, cocaine and cannabis in oral fluid from truck drivers driving through highways in the state of Sao Paulo

Henrique Silva Bombana 13 December 2016 (has links)
No Brasil, em 2014, os acidentes de trânsito contabilizaram mais de 44 mil óbitos. Já foi relatado na literatura científica a relação entre o uso de drogas por motoristas de caminhão a fim de manterem a exaustiva jornada de trabalho a que são submetidos. O presente estudo teve como objetivo avaliar a frequência do uso de drogas ilícitas por motoristas de caminhão através de análises toxicológicas em amostras de fluido oral. Motoristas de caminhão foram abordados de forma aleatória por policiais rodoviários federais e convidados a participar dos Comandos de Saúde nas Rodovias, evento de promoção à saúde dos caminhoneiros. Os motoristas que aceitaram participar do estudo doaram uma amostra de fluido oral, coletado com o dispositivo Quantisal(TM), e responderam a um questionário estruturado para coleta de dados sociodemográficos. As amostras de fluido oral foram submetidas à análise de triagem para cocaína, anfetamina e delta9-tetrahidrocanabinol (delta9-THC) por ELISA, sendo esse estudo pioneiro na utilização dessa técnica para triagem de amostras de fluido oral no trânsito. As amostras que apresentaram resultados positivos foram confirmadas por cromatografia gasosa acoplada à espectrometria de massas (GC-MS). No período de desenvolvimento desse estudo foi possível o envio das amostras positivas na etapa de triagem para o Instituto Norueguês de Saúde Pública para confirmação por cromatografia líquida de ultra eficiência acoplada à espectrometria de massas em tandem (UPLC-MS/MS). Além das três substâncias já pesquisadas no estudo foram analisadas a presença de outras 29, dentre drogas ilícitas e medicamentos psicoativos. Foram incluídos 762 motoristas. Das amostras analisadas, 5,2% (n=40) apresentaram resultado positivo para algum tipo das drogas estudadas. A cocaína foi a droga mais encontrada (n=16), seguida pela anfetamina (n=11) e delta9-THC (n=4). Ainda, três amostras apresentaram resultados positivos para cocaína e ?9-THC e uma amostra para cocaína e anfetamina. Além da cocaína, anfetamina e ?9-THC, com a confirmação por UPLC-MS/MS foram detectados outros fármacos psicoativos, o meprobamato e o alprazolam, (duas amostras testaram positivo para anfetamina e meprobamato uma para anfetamina e alprazolam e outra amostra para cocaína e meprobamato). Os motoristas com amostras positivas eram mais jovens, com menos escolaridade, mais inexperientes, possuíam uma jornada de trabalho mais extensa e percorriam percursos mais longos. Esse fato alerta, sem dúvida, a necessidade da ampliação de estudos nacionais sobre o uso de substâncias psicoativas, incluindo as ilícitas e medicamentos, para melhor entendimento na comunidade científica e permitindo a implementação de políticas públicas voltadas à prevenção e fiscalização do uso dessas substâncias, com o objetivo de reduzir a morbimortalidade resultante dos acidentes de trânsito nacionais / In Brazil, in 2014 it caused more than 44 thousand deaths. In Brazil is already described in the literature the use of psychoactive substances by truck drivers to maintain their extensive work schedule and stay awake for several hours. Important highways cross through Sao Paulo to other regions from Brazil and to countries from Latin America. This study aims to demonstrate the prevalence of illicit drug use by truck drivers on the State of Sao Paulo through toxicological analyses on oral fluid. Truck drivers were randomly stopped by police officers on federal roads during morning hours. Oral fluid samples were collected using the Quantisal(TM) device. In addition, a questionnaire concerning sociodemographic characteristics and health information was administered. Oral fluid samples were screened for amphetamine, cocaine, and tetrahydrocannabinol (?9-THC) by ELISA. The samples were confirmed by GC-MS, using validated methods for the substances of interest. During the development of this study we had the opportunity to send the positive samples to the Norwegian Institute of Public Health for confirmation using UPLC-MS/MS. Besides cocaine, amphetamine and delta9-THC the samples were tested for others 29 samples, including illicit drugs and psychoactive medicines. 762 drivers agreed to participate. Of the total samples 5.2% (n = 40) tested positive for drugs. Cocaine was the most found drug (n = 16), followed by amphetamine (n = 11) and delta9-THC (n = 4). Furthermore, three samples tested positive for cocaine and delta9-THC and one sample for cocaine and amphetamine. The confirmation using UPLC-MS/MS pointed another two substances that were not tested previously, meprobamate and alprazolam (two samples tested positive for amphetamine and meprobamate, one for amphetamine and alprazolam and another one for cocaine and meprobamate). Drivers presenting positive samples were younger, with less education, less experienced, had a longer work schedule and drove longer distances. This fact shows that, undoubtedly, there is need for more national studies regarding the use of psychoactive substances, illicit and medicines, for a better understand by the scientific community and those responsible for implementation of public policies aiming the control of the use of these substances, in order to, one day, we were able to indeed reduce traffic accidents mortality in our country
233

Adequação do design de interiores de cabines-leito de caminhões semipesados e pesados no Brasil às necessidades relacionadas ao uso como habitações temporárias / Suitability of the interior design of light-heavy-duty truck cabins in Brazil to the needs related to the use as temporary dwellings

Ana Paula Scabello Mello 03 August 2017 (has links)
A tese apresenta os aspectos relevantes que emergiram de pesquisa qualitativa e de abordagem fenomenológica e observacional a respeito da adequação do design de interiores de cabines-leito de caminhões semipesados e pesados aos usuários no Brasil, com enfoque nas atividades relacionadas ao habitar, com base na percepção de usuários, na observação da pesquisadora e na avaliação de especialistas. Aspectos socioculturais, comportamentais, necessidades e hábitos dos usuários brasileiros em relação às cabines-leito, bem como adaptações e customizações realizadas para adequá-las às atividades ali realizadas, foram levantados em campo, por meio de observação e registros de imagens de vinte e cinco cabines-leito em uso, bem como entrevistas semiestruturadas com seus usuários. Os levantamentos foram realizados em locais de parada e concentração de caminhões nos estados de São Paulo e Pernambuco e contemplaram caminhões provenientes das regiões Sudeste, Sul, Nordeste e Centro-Oeste. Foram realizadas entrevistas semiestruturadas com seis especialistas de empresas fabricantes de caminhões, com o objetivo de investigar como é avaliada por eles a adequação de cabines-leito desenvolvidas para o mercado global ao contexto e aos usuários no Brasil, bem como os métodos de pesquisa com usuários utilizados no desenvolvimento de cabines-leito nas principais empresas. Foram entrevistados também dois profissionais de empresas que realizam adaptações e customizações dos interiores de cabines-leito. O objetivo geral desta tese é apresentar aspectos relevantes sobre o uso de interiores de cabines-leito de caminhões semipesados e pesados no Brasil como habitações temporárias. Pretende-se, assim, fornecer contribuições e parâmetros para o desenvolvimento de cabines-leito de caminhões que atendam às necessidades dos usuários no contexto brasileiro. / This thesis presents relevant aspects that emerged from qualitative research, with a phenomenological and observational approach, on the suitability of the interior design of sleeper cabins in semi-heavy and heavy trucks to users in Brazil, focusing on activities related to their living based on user perception, in observation of the researcher and expert evaluation. Socio-cultural and behavioral aspects, needs and habits of Brazilian users in relation to sleeper cabins, as well as adjustments and customizations made to suit the activities carried out by such users, were raised in the research field through observation and records of twenty-five sleeper cabins in use, as well as semistructured interviews with their users. The surveys were conducted at rest areas and truck stops in the States of São Paulo and Pernambuco and included trucks traveling from the Southeastern, Southern, Northeastern and Midwestern regions. Semistructured interviews were conducted with six truck manufacturer experts aiming at investigating how they evaluate the adequacy of sleeper cabins designed for the global market context and for users in Brazil, as well as the user research methods used in the development of sleeper cabins in major companies. Two professionals from companies that perform adjustments and customizations of the interior of sleeper cabins were also interviewed. The general objective of this thesis is to present relevant aspects on the use of sleeper cabin interiors in semi-heavy and heavy trucks in Brazil as temporary housing. Hence, it aims at providing contributions and parameters for the development of truck sleeper cabins that meet the needs of users in the Brazilian context.
234

Eicher 2020+

Allison, Philip, Pye, Michael January 2012 (has links)
Investigating the Indian society, culture and truck market to develop a list of criteria (design brief) for an optimal truck for these markets. These criteria will be used as a starting point for the design process of designing the truck. Investigations in Sweden (at Volvo) and in India (at Eicher). Research conducted through design methods and interviews with stakeholders.   It is the goal of this thesis to create two examples of what a domestically built truck for the Indian market could be.
235

Design and implementation of an integrated algorithm for the vehicle routing problem with multiple constraints

Moolman, A.J. (Alwyn Jakobus) 27 May 2005 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MSc (Industrial Systems))--University of Pretoria, 2006. / Industrial and Systems Engineering / unrestricted
236

Estudio de mejora integral en la empresa transportes Pereda S.R.L.

Cabrera-Llerena, Gresia-Fernanda, Pereda-Jaqquehua, Estefani-Daniela January 2015 (has links)
El presente trabajo consta de una revisión de la situación actual de la empresa Transportes Pereda S.R.L. / This document describes an opportunity to improve and achieve the actual situation of the company “Transportes Pereda S.R.L” / Trabajo de investigación
237

An Econometric Analysis of Cost Changes in U.S. Trucking and the Implications of Implementing the NAFTA Trucking Provisions

Peterson, Erica Kay January 2007 (has links)
The United States trucking industry underwent deregulation starting in 1980. There was much opposition to the process in fears that trucking companies would be adversely affected by increased competition. There were also many proponents and researchers who proved that the increased competition due to regulatory reform only helped strengthen the industry by forcing firms to become more cost efficient. There has been similar opposition and support for the trucking provisions of NAFTA. Although the provisions have not been fully implemented, the trucking industry is well aware it will only be a matter of time. In early 2002 it was announced that the process to begin implementing the trucking provisions would begin in mid-2002. Many in the industry and other groups have opposed implementing the provisions, concerned that U.S. trucking firms would be subject to competition from Mexican firms, just as they feared trucking firms would be adversely affected by deregulation more than 25 years ago. This thesis analyzes the effects the 2002 announcement of the process to begin implementing the trucking provisions has had on the cost structure of the industry. It uses a translog cost function to determine if firms have become more efficient in the years following the announcement in anticipation of increased competition from Mexican firms after the provisions are fully implemented. The translog cost function is used to determine what effects the NAFTA variable has had on costs and what specific operating characteristics have caused the costs to increase or decrease.
238

Vliv uložení nákladu na bezpečnost jízdy nákladního vozidla / Impact of Load Placing on the Driving Safety of Lorries

Novotný, Michal January 2010 (has links)
The objection of this dissertation is to examine effects of stowed cargo on safety driving of a vehicle. Based on general experience of weighing trucks and monitoring of cargo fixture, my attempt was to summarize related legislative conditions of the operation of trucks in terms of payload, weighing and stowing of cargo. In the first part I worked on consistent methodology of stowing and fastening of cargo on trucks. I've included various methods of loading cargo and different ways of fastening and their calculations. The main body of the second part is a practical methodology of inspectional weighing of trucks on the road. In this section I took into account the current method and procedure of inspectional weighing and measuring of trucks. During my trial weighing of different types of trucks I proved that the key factor for safe seating and lashing of load on a vehicle is determining center of gravity of the vehicle. I solve this problem in detail in the last part of my work.
239

Electric Road Systems for Trucks

Edfeldt, Erica, Andersson, Sanna January 2013 (has links)
An increased use of electricity in vehicles is considered an alternative to decrease the usage of fossil fuels. For private cars, plug-in electric vehicles using batteries are continuously being improved. However, the battery technology of today is not sufficient for trucks if they are to use only electricity. The battery technology is not sufficient to be able to supply the truck with enough propulsion energy to perform an entire drive. However, the hybrid drive technology enables a power recovery and charges the battery when the vehicle applies its brakes. The fuel usage can thereby be decreased through the energy recovery. This master thesis examines the potential of electric road systems, ERSs, which enables a continuous electricity supply to the vehicle when in motion. Similar technologies as an ERS has been used for a long time for trams, trolleybuses and trains, and historically there have also existed cases of electric truck systems. In this thesis the potential for ERSs is examined from the haulage contractor companies’ perspective, which would be users of this system. The potential is in regard to the energy usage per km, the CO2 emissions per km and the cost per km for an ERS vehicle (a hybrid vehicle using an ERS) compared to a hybrid vehicle and to a conventional vehicle. The cost per km includes energy cost, cost for using the ERS infrastructure and the additional vehicle cost. The method used in this study was first to create a broad picture of the concept of ERSs through reading articles, reports, web pages and through conducting interviews with stakeholders within the ERS market. The second part of the method was to create a technology model and an economic model. The models investigate the potential for ERSs through three different cases: a Distribution Case, a Long-Haulage Case and a Mining Case. For all three cases, the energy usage, the cost and the CO2 emissions per km for using a conventional vehicle, a hybrid vehicle and ERS vehicle were generated. Four alternative future scenarios were also tested, in which factors such as energy costs and infrastructure costs were varied. The results show the energy usage, the CO2 emissions and the profitability from the haulage contractor companies’ perspective. The results show that ERSs are not profitable for the Distribution Case in any of the tested scenarios. For the Long-Haulage Case, however, it is profitable in four out of the five tested scenarios. The Mining Case shows mixed profitability results, many times being just above or just below profitable. The energy usage decreased for all the cases and scenarios. Because of this, in combination with the relatively clean electricity production in Sweden, the decrease in CO2 emissions is very large. The 3 conclusions from this thesis are therefore that long-haulage routes show great potential for using ERSs, mining cases have some potential for using ERSs and if distribution routes are to use ERSs this would be only for lowered fossil fuel usage and environmental purposes. / För att minska användandet av fossila bränslen anses ökad användning av elektricitet i fordon vara ett potentiellt alternativ. För laddelbilar inom personbilssektorn förbättras batteritekniken ständigt. Dock ser inte batteriteknikens utveckling ut att vara tillräcklig för lastbilar om de ska kunna köra på enbart el. Även om batteritekniken inte är tillräcklig för att lastbilen ska kunna köra på enbart el så kan batterier användas i lastbilshybrider. Hybridsystemet möjliggör en energiåtervinning där batteriet kan laddas när fordonet bromsar. Bränsleanvändningen kan därmed minskas genom energiåtervinningen. Detta examensarbete utreder potentialen för elektriska vägsystem. Elektriska vägsystem möjliggör kontinuerlig överföring av elektricitet till lastbilar medan de kör. Liknande tekniker har länge använts för spårvagnar, trådbussar, tåg och även i viss utsträckning för trådlastbilar. I detta examensarbete utreds potentialen för elektriska vägsystem utifrån åkeriers perspektiv, eftersom dessa i så fall kommer att vara de som använder systemet. Potentialen bedöms genom att jämföra energianvändning per kilometer, CO2-utsläpp per kilometer och kilometerkostnad för en elvägslastbil jämfört med en konventionell lastbil och jämfört med en hybridlastbil. Kilometerkostnaden innefattar energikostnad, kostnad för att använda elvägsinfrastrukturen och den ytterligare fordonskostnaden. Metoden som användes i denna studie var först att skapa en bred bild av konceptet elektriska vägsystem genom att läsa artiklar, rapporter, hemsidor och att utföra intervjuer med aktörer inom elektriska vägsystem. Den andra delen av metoden var att skapa en ekonomisk och teknisk modell. Tre olika fall modellerades: ett distributionsfall, ett fjärrtrafikfall och ett gruvtransportfall. För dessa tre fall så genererades energianvändningen, CO2-utsläppen och kostnaden per km vid användning av en konventionell lastbil, en hybridlastbil och en hybrid som använder elektriska vägsystem. Fyra alternativa framtidsscenarion testades också, för vilka parametrar såsom energikostnader och infrastrukturkostnader varierades. Alla resultat visar energianvändningen, CO2-utsläppen och lönsamheten utifrån ett åkeriperspektiv. Resultaten visar att elektriska vägsystem inte är lönsamma för distributionsfallet i något av de testade scenarierna. För fjärrtrafik är det lönsamt i fyra av de fem testade scenarierna. Gruvtrafikfallet visar på blandade resultat, där det ofta är precis lönsamt eller nästan lönsamt med elektriska vägsystem. Energianvändningen minskar för alla fall och scenarier. Detta tillsammans med Sveriges relativt rena elektricitetsproduktion innebär att CO2-utsläppen minskar kraftigt. Slutsatserna från detta examensarbete är därför att fjärrtrafik påvisar stor potential för elektriska vägsystem, gruvtrafik har viss potential och distributionstrafik bör endast använda elektriska vägsystem av miljömässiga och fossilbränslereducerande skäl.
240

Electric-road freight transport, Arlanda-Rosersberg logistic flow and environmental analysis.

Wang, Qiuchen, Mompo, Santiago January 2014 (has links)
The expected economic and social growth, joint with the increase on the demand of services and goods that this will cause, will become an environmental problem (emissions and noise) as well as a logistical problem (congestion) that needs to be solved. The transport sector has to reduce drastically the use of fossil fuels and Sweden’s goal is to achieve a fossil independent vehicle fleet by 2030. It is expected that 2/3 of the traffic volume of trucks in Sweden will be performed along electrified roads. The most efficient way to achieve this is to use electricity and now that the technology to power trucks without the need of huge batteries has been tested and approved, is time to develop the infrastructure needed and study its impact in transportation and logistics. An electric road is planned to be operative around 2020 from Rosersberg logistics hub to Arlanda airport cargo city. The objective is to transfer goods from the logistic area to the freight terminal by the use of electric trucks. It will optimize the transit of logistics flow in the area, reduce emissions and release the traffic pressures on E4 at the same time. Arlanda airport used to have a restriction on the emission rate of all the companies operating inside Arlanda, the emissions of the trucks that drive the cargo outside Arlanda was also taken into account. This means that in order to be below the maximum levels, the high ground transport emissions limited the number of planes that could fly. Affecting therefore the capacity of handling bigger volumes and passengers. So in order to prevent this situation from happening again in the future (more environmental restrictions will appear) the best solution for all the parts involved is to give priority to sustainability in transport planning. The aim of this project is to come up with conclusions and forecasts of the whole transportation network according to the logistics needs, by analysing the economic, environmental and logistic impacts of using the El-road. The result expected is to provide a clearer overall picture of the logistic flows between Rosersberg, Arlanda Airport, Gavle container and nearby locations, such as Stockholm or Uppsala. As well as analyse the possible scenarios that might develop once the El-road is operating. Due to the nature of our data we decided to use qualitative and subjective methods rather than quantitative ones. AHP (Analytic Hierarchy Process, Saaty 1970), will enable us to derive ratio scales from paired comparisons by defining the different criteria (cost, time, operations and sustainability) and assigning values to their respective sub criteria. These values will be assigned by each of the companies working inside Arlanda, since the goal is to define the best possible scenario for them in the future. The other method we will use is the decision tree analysis, this model of decisions and possible consequences that can occur will show a graph of all the variables that must be taken into account while defining the issues that will lead to one scenario or another. We consider it the best method to analyse and show how many facts can affect the final scenario outcome of this project.

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