860 resultados para Road profiles


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This thesis presents a system to recognise and classify road and traffic signs for the purpose of developing an inventory of them which could assist the highway engineers’ tasks of updating and maintaining them. It uses images taken by a camera from a moving vehicle. The system is based on three major stages: colour segmentation, recognition, and classification. Four colour segmentation algorithms are developed and tested. They are a shadow and highlight invariant, a dynamic threshold, a modification of de la Escalera’s algorithm and a Fuzzy colour segmentation algorithm. All algorithms are tested using hundreds of images and the shadow-highlight invariant algorithm is eventually chosen as the best performer. This is because it is immune to shadows and highlights. It is also robust as it was tested in different lighting conditions, weather conditions, and times of the day. Approximately 97% successful segmentation rate was achieved using this algorithm.Recognition of traffic signs is carried out using a fuzzy shape recogniser. Based on four shape measures - the rectangularity, triangularity, ellipticity, and octagonality, fuzzy rules were developed to determine the shape of the sign. Among these shape measures octangonality has been introduced in this research. The final decision of the recogniser is based on the combination of both the colour and shape of the sign. The recogniser was tested in a variety of testing conditions giving an overall performance of approximately 88%.Classification was undertaken using a Support Vector Machine (SVM) classifier. The classification is carried out in two stages: rim’s shape classification followed by the classification of interior of the sign. The classifier was trained and tested using binary images in addition to five different types of moments which are Geometric moments, Zernike moments, Legendre moments, Orthogonal Fourier-Mellin Moments, and Binary Haar features. The performance of the SVM was tested using different features, kernels, SVM types, SVM parameters, and moment’s orders. The average classification rate achieved is about 97%. Binary images show the best testing results followed by Legendre moments. Linear kernel gives the best testing results followed by RBF. C-SVM shows very good performance, but ?-SVM gives better results in some case.

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This paper aims to present three new methods for color detection and segmentation of road signs. The images are taken by a digital camera mounted in a car. The RGB images are converted into IHLS color space, and new methods are applied to extract the colors of the road signs under consideration. The methods are tested on hundreds of outdoor images in different light conditions, and they show high robustness. This project is part of the research taking place in Dalarna University / Sweden in the field of the ITS.

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The purpose of this study was to investigate pacing-profile differences during the 90 km Vasaloppet ski race related to the categories of sex, age, and race experience. Skiing times from eight sections (S1 to S8) were analyzed. For each of the three categories, 400 pairs of skiers were matched to have a finish time within 60 seconds, the same start group, and an assignment to the same group for the other two categories. Paired-samples Student’s t-tests were used to investigate sectional pacing-profile differences between the subgroups. Results showed that males skied faster in S2 (P=0.0042), S3 (P=0.0049), S4 (P=0.010), and S1–S4 (P<0.001), whereas females skied faster in S6 (P<0.001), S7 (P<0.001), S8 (P=0.0088), and S5–S8 (P<0.001). For the age category, old subjects (40 to 59 years) skied faster than young subjects (19 to 39 years) in S3 (P=0.0029), and for the other sections, there were no differences. Experienced subjects (≥4 Vasaloppet ski race completions) skied faster in S1 (P<0.001) and S1–S4 (P=0.0054); inexperienced skiers (<4 Vasaloppet ski race completions) had a shorter mean skiing time in S5–S8 (P=0.0063). In conclusion, females had a more even pacing profile than that of males with the same finish time, start group, age, and race experience. No clear age-related pacing-profile difference was identified for the matched subgroups. Moreover, experienced skiers skied faster in the first half whereas inexperienced skiers had higher skiing speeds during the second half of the race.

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Bacterial isolates from natural sites with high toxic and heavy metal contamination more frequently contain determinants for resistance to antimicrobials. Natural strains were isolated from the ingesta and external slime of Salmo salar (Linnaeus, 1758) and Salvelinusjontinalis (Mitchell, 1814). Fish specimens were acquired from Casco Bay hatcheries, Casco, ME where there is no history of antibiotic use. Seventy-nine bacterial strains, including many well-documented salmonid commensals (an association from which the fish derives no benefit), were identified using 165 rRNA gene sequencing. Mercury resistant isolates were selected for initially on 25μM HgCI2. Strains were then grown at 20-24°C on Trypticase Soy Agar (TSA) plates containing 0-1000μM HgCl2 or 0-130μM Phenyl Mercuric Acetate (PMA). Mercury in the hatchery feed water due to ubiquitous non-point source deposition has selected for the mercury resistance observed in bacterial strains. Antibiotic resistance determinations, as measured by Minimum Inhibitory Concentration MIC) assays were performed on the 79 bacterial isolates using Sensititrel antimicrobial susceptibility panels. A positive linear correlation between the mercury (pMA and HgCl2) MIC's and antibiotic resistance for all observed strains was demonstrated. Conjugation experiments with Pseudomonas, Aeromonas, and Azomonas donors confirmed phenotypic transfer of penicillin and cephem resistances to Escherichia coli DH5a recipients. Conjugation experiments with Pseudomonas donors showed minimal transfer of tetracycline and minoglycoside resistances to Escherichia coli DH5a recipients. Our study suggests that the accumulation of antimicrobial resistances observed in these natural bacterial populations may be due to the indirect selective pressure exerted by environmental mercury.

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The plot consists of the progression which the characters undergo. For the old man, the plot is his movement away from the earthly existence of the farm and into the physical process of the seasons. For the older grandson, it is the movement away from the past, symbolized by the farm, and into the present symbolized by his marriage and coupling with society. For the younger grandson, the movement is from childhood to the maturity which being alone demands in order for him to survive.

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Marine Corps Capt. Erik Quist ’99 had fought in two wars. Now he fights again as he recovers from severe wounds suffered in Afghanistan.

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Este estudo adota a perspectiva experiencial, trazendo a noção de consumo hedônico e de experiência de consumo para o âmbito do marketing e do comportamento do consumidor. Partese do pressuposto de que entender o consumo exige ir além do processo de decisão de compra e admitir que aquilo que os consumidores fazem e a forma como utilizam os bens adquiridos também influencia seus comportamentos. Mas, acima de tudo, exige a visão do consumidor como um indivíduo emocionalmente envolvido com o consumo, processo pelo qual estímulos sensoriais, a imaginação e aspectos emotivos são procurados e apreciados. A investigação teve por objetivo compreender a experiência dos consumidores em situações de uso e consumo dos produtos através da análise dos elementos que a compõem: o contexto, os estímulos sensoriais, os processos cognitivos, as respostas afetivas, as atividades e o processo de avaliação do produto e da experiência em si. A categoria de produtos escolhida foi a de veículos fora-de-estrada, em função do potencial multiuso e da possibilidade de proporcionar desde simples viagens a grandes aventuras. Para atingir os objetivos propostos foi utilizada a Técnica de Elicitação Fotográfica (PET), que permitiu à pesquisadora se aproximar da experiência real vivenciada pelos consumidores através das imagens visuais que os mesmos foram solicitados a trazer para as entrevistas. Os resultados encontrados apontam não apenas para a riqueza e o profundo entendimento a respeito dos consumidores possibilitado pela análise de suas experiências, mas também o quanto a estimulação visual pode ser uma grande aliada dos pesquisadores quando o objetivo da investigação é entender comportamentos de consumo, a relação das pessoas com seus objetos de desejo, as relações sociais que são possibilitadas através das posses e como as experiências em si (e não apenas as características funcionais dos produto) contribuem para a expressão da identidade, auto-conceito e estilo de vida dos consumidores.

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O empreendedor tem intrigado acadêmicos há anos. Portanto, inúmeras abordagens têm sido aplicadas para entender quem é o empreendedor, sua personalidade e comportamentos. As principais escolas de estudo sobre o tema são a escola de traços psicológicos e a escola de processos ou comportamentos. No entanto, a academia ainda carece de uma definição concreta do indivíduo responsável pelo fenômeno do empreendedorismo. Em uma tentativa de esclarecer essa questão esta pesquisa sugere uma nova abordagem para a compreensão da pessoa do empreendedor com base nos valores pessoais de Schwartz. O objetivo da tese é compreender o perfil de valores de empreendedores sociais e comerciais a fim de determinar as semelhanças e diferenças nas suas preferências de valores que orientam o comportamento empreendedor de ambos e o enfoque social de um e privado do outro. Para este fim a versão mais curta do Questionário de Perfil Valores de Schwartz foi aplicada a uma amostra de 44 empreendedores sociais e 71 comerciais. A primeira proposição da tese era que os empreendedores sociais e comerciais possuiriam um perfil de valores. A segunda era que este perfil de valores seria determinado pelo princípio organizador da ansiedade com preferência pelos valores “livres de ansiedade” em decorrência das características empreendedoras que enfatizam busca pela auto-expansão, crescimento e promoção do alcance de metas. Dessa forma os valores mais importantes para ambos os tipos de empreendedores seriam auto-determinação, estimulação, hedonismo, universalismo e benevolência. A terceira proposição era que os empreendedores sociais e comerciais atribuiriam a mais alta importância ao valor auto-determinação. A quarta propunha que os empreendedores sociais dariam maior importância do que os comerciais para benevolência e universalismo visto que esses valores presumem apreciação pelos outros, preservação e valorização do bem-estar das pessoas mais próximas bem como de qualquer ser vivo em geral. Os resultados das análises descritivas e dos testes de hipóteses apontam para a validação de todas as proposições menos a última. No entanto, apesar da quarta proposição não haver sido estatisticamente comprovada, houve uma leve tendência dos empreendedores sociais darem maior importância do que os comerciais aos valores de auto-transcendência. Conseqüentemente, para maiores esclarecimentos sobre esse tópico, outros estudos com amostras maiores e randômicas devem ser realizadas.

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This work was carried out to verify the effect of a glyphosate-based herbicide on Jundia hormones (cortisol, 17 beta-estradiol and testosterone), oocyte and swim-up fry production. Earthen ponds containing Jundia females were contaminated with glyphosate (3.6 mg/L); blood samples were collected from eight females from each treatment immediately before, or at 1, 10, 20 30 and 40 days following contamination. A typical post-stress rise in cortisol levels was observed at the 20th and 40th days following exposure to glyphosate. At the 40th day, 17 beta-estradiol was decreased in the exposed females. A similar number of oocytes were stripped out from females from both groups, however, a lower number of viable swim-up fry were obtained from the herbicide exposed females, which also had a higher liver-somatic index (LSI). The results indicate that the presence of glyphosate in water was deleterious to Rhamdia quelen reproduction, altering steroid profiles and egg viability. (c) 2006 Elsevier B.V. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)