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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.
21

Revitalizace toku rybím přechodem / Revitalization of river on the way fish-passing facility building

Šuba, Dušan January 2014 (has links)
This diploma thesis has two parts. The first section contains basic kinds of fish passing. The second part deals with the design of fish passing on the river Dřevnice in the village Louky. In the program HEC-RAS was simulated situation where the fish ladder is in operation.
22

Hotspot analysis of wildlife vehicle collisions of BR-262, Mato Grosso Do Sul, Brazil and recommendations for mitigation efforts

Unknown Date (has links)
Road networks have significant impacts on ecosystems through deforestation, rapid land conversion and wildlife-vehicle collisions. Road ecology seeks to analyze the spatial and biological patterns of collisions to understand the effect of roadways and best inform transportation planning in mitigating these threats. 215 km of roadway BR-262, that bisects critical habitat of the Brazilian Cerrado and Pantanal in southwest Brazil, was analyzed between April 2011 and June 2012 to assess how biological, physical and landscape characteristics affect clustering of collisions. 518 collisions, representing 40 species, were found to be seasonally clustered between the unimodal rain and flood pulse in a February-March-April window and were spatially clustered over the study area in relation to cash crop and cattle ranching land-use and the rural low-lying Pantanal floodplain. Mitigation seeks to work with local communities and transportation agencies to facilitate fauna safe crossing through the roadway that do not conflict with drivers. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
23

Eficácia da restrição de velocidade e outras ações na prevenção de acidentes em travessias urbanas de rodovias / Effectiveness of speed restriction and other measures in the prevention of accidents at urban highway crossings

Amin, Jorge Carlos 12 March 2012 (has links)
As travessias urbanas de rodovias constituem-se um local crítico para a ocorrência de acidentes de trânsito. Dessa forma, diversas ações de engenharia são empregadas para a redução do número e da gravidade dos acidentes. Contudo, existem poucos estudos sobre a eficácia dessas ações. No presente trabalho foram utilizadas duas metodologias para a avaliação da eficácia, através de estudos observacionais, são elas: \"antes - depois\" ingênuo e o método do grupo de comparação, aplicadas em vários segmentos rodoviários caracterizados como travessias urbanas que receberam ações de engenharia para a redução de acidentes. O primeiro método foi aplicado a todas as ações e o segundo apenas para duas ações. As informações utilizadas neste trabalho foram solicitadas às concessionárias das rodovias do Estado de São Paulo. Foram analisadas sete ações de engenharia: 1) redução de velocidade em conjunto com outras medidas; 2) implantação de defesa de New Jersey elevada; 3) implantação de dispositivo em desnível; 4) cruzamento de pedestres em nível em área demarcada; 5) implantação de passarela; 6) implantação de ciclovia; 7) passagem superior e tela para impedir a passagem de pedestres em nível. Os resultados encontrados demonstram que ação 1 reduz em média em 27% o número total de acidentes tanto para o método ingênuo como para o método de grupo de comparação. A ação 2 foi a única ação com resultado negativo, com aumento de 19% no número de acidentes totais e de 42% no número de acidentes com feridos e mortos. A ação 3 teve uma redução no número total de acidentes em torno de 27%. A ação 4 teve uma redução de 35% no número total de acidentes. A ação 5 teve uma redução no número total de acidentes em torno de 40%, através do método ingênuo, contra 30% pelo método de grupo de comparação. A ação 6 teve uma redução no número de acidentes totais de 30%. A ação 7 não teve uma redução expressiva no número total de acidentes, contudo teve uma redução de 32% no número de feridos e mortos. / The urban highway crossings are a critical place for occurrence of traffic accidents. Thus, several engineering measures are employed to reduce the number and severity of accidents. However, there are few studies about the effectiveness of these actions. In this study two methods were used to evaluate the effectiveness, through observational studies, they are: \"before - after\" naive method and the comparison group, applied in various segments characterized as urban highway crossings in which they had been implemented measures to reduce accidents. The first method was applied to all measures and the second only for two measures. The data used in this study were obtained from the concessionaire of highways of the State of Sao Paulo. It was analyzed seven engineering measures: 1) reduction of speed in conjunction with other measures; 2) implementation of New Jersey defense with higher height; 3) implementation of grade separation structure; 4) level pedestrian crossings in areas demarcated, 5) implementation runway; 6) implementation of bike path; 7) footbridge and barriers to prevent the passage of pedestrians. The results show that the first measure reduces on average by 27% the total number of accidents for both the naive method and to the method of comparison group. The second measure was the only action with negative results, with 19% increase in the number of total accidents and 42% in the number of accidents with injuries and deaths. The third measure had a reduction in the total number of accidents around 27%. The fourth measure had a 35% reduction in the total number of accidents. The fifth measure had a reduction in the total number of accidents by 40%, through the naive method, compared to 30% by the method of comparison group. The sixth action had a reduction in total accidents by 30%. The seventh action had not a significant reduction in the total number of accidents, yet had a 32% reduction in the number of injuries and deaths.
24

Avaliação de raças maternas em cruzamento com carneiros Dorper na produção de cordeiros para abate precoce / Evaluation of dam breeds in crossing with Dorper sire breed for production of early slaughtering lambs

Issakowicz, Juliano 08 April 2015 (has links)
Com este estudo objetivou-se avaliar ovelhas da raça Morada Nova (MN) e Santa Inês (SI) quanto à infecção parasitária e desempenho reprodutivo e produtivo quando acasaladas ou cruzadas com reprodutores da raça Dorper (D), assim como, o desempenho e as características de carcaça e da carne dos cordeiros Morada Nova (MM), Santa Inês (SS) e de seus meio sangue ½ Dorper x ½ Morada Nova (MD) e ½ Dorper x ½ Santa Inês (SD) terminados em confinamento. Foram utilizadas 51 ovelhas (MN) com 33,1 ± 4,98 kg de peso e 52 ovelhas (SI) com 51,8 ± 7,07 kg, todas multíparas com idades entre 2 a 4 anos. As ovelhas permaneceram em pastagem de Panicum maximum (cultivar Aruana) e no terço final de gestação e na lactação foram mantidas em baias coletivas recebendo silagem de milho ad libitum e 400 g/animal/dia de concentrado. Após a desmama, foram utilizados 32 cordeiros sendo 8 MM (peso 15,0 ± 1,0 Kg), 8 SS (peso 18,4 ± 1,0 Kg), 8 MD (peso 16,1 ± 1,0 Kg) e 8 SD (peso 21,3 ± 1,0 Kg) com aproximadamente 70 dias de idade e terminados em confinamento com dieta composta de 40 % de silagem de milho e 60 % de concentrado e abatidos aos 35 kg de peso aproximadamente. Em ambas as raças maternas a infecção parasitária foi caracterizada pela predominância de parasitas do gênero Haemonchus, que se agravou no pré e pós-parto com as ovelhas MN capazes de manter a infecção mais baixa aos 30 dias pós-parto. O grau de infecção parasitária não foi suficiente para alterar negativamente as variáveis hematológicas que se mantiveram dentro da normalidade para a espécie, com algumas diferenças entre as raças de acordo com as datas de coleta. Ambas as raças maternas apresentaram bom desempenho reprodutivo, produzindo crias ao nascimento e à desmama mais pesadas quando cruzadas com reprodutores Dorper e Fêmeas MN cruzadas com reprodutores Dorper produzindo a desmama, crias com pesos semelhantes a ovelhas SI acasaladas. Cordeiros cruzados SD e MD apresentam desempenho e características de carcaça semelhantes, com maior deposição de tecido em regiões de maior valor comercial quando comparados aos cordeiros puros. Quanto a carne, não foi identificada diferença entre os grupos estudados para as características de cor, maciez e suculência, mas os cordeiros cruzados apresentaram carne com menor quantidade de gordura, com os cordeiros SD expondo uma gordura com melhor perfil nutricional para o consumo humano do que de cordeiros MD / The objectives of this study were to evaluate the parasitic infection; reproductive and productive performance of Morada Nova (MN) and Santa Inês (SI) sheep crossed with Dorper rams; and to evaluate productive performance; carcass and meat characteristics of Morada Nova (MM) and Santa Inês (SS) lambs and that of the crossbred ½ Dorper x ½ Morada Nova (MD) and ½ Dorper x ½ Santa Inês (SD) lambs, finished in feedlot system. Fifty one MN sheep (33,1 ± 4,98 kg initial body weight - BW) and 52 SI sheep (51,8 ± 7,07 kg BW), all multiparous, aging from 2 to 4 years old were used. The sheep were kept in Panicum maximum cv. Aruana pasture and from the final third of gestation up to lactation period they were housed in collective pens, receiving corn silage ad libitum and 400 g/animal/day of concentrate. After weaning, 32 lambs, 8 MM (15,0 ± 1,0 Kg BW), 8 SS (18,4 + 1,0 Kg BW), 8 MD (16,1 ± 1,0 Kg BW) and 8 SD (21,3 ± 1,0 Kg BW) aging about 70 days old, finished in feedlot system and fed on a 40:60 corn silage and concentrate diet were slaughtered around the body weight of 35 Kg. In both maternal breeds the parasitic infection was characterized by the predominance of Hamonchus genus parasites, and it has increased in pre and postpartum periods; the MN sheep were capable of maintaining reduced parasitic infection at 30 days after giving birth. The parasitic infection has not affected blood parameters, which were maintained in the reference range of the species, with some differences being observed between breeds according to blood collection dates. Both maternal breeds presented good reproductive performance, producing lambs that presented increased birth and weaning weight when crossed with Dorper ram; MN sheep when crossed with Dorper ram have produced lambs that presented weaning weights similar to that of lambs produced by SI sheep when mated with SI ram. Crossbred lambs SD and MD presented similar productive performance and carcass characteristics, with increased tissue deposition in more commercially appreciated areas when compared with pure breed lambs. In the meat characteristics evaluations, no differences were observed between the studied groups for meat color, softness and juiciness but the crossbred lambs produced meat with reduced fat content, with SD lambs presenting fat profile more suitable for human consumption than MD lambs
25

Caracterização de espécies de Trichogramma Westwood (Hymenoptera: Trichogrammatidae), parasitoides de ovos de Erinnyis ello (L.) (Lepidoptera: Sphingidae) / Characterization of the Trichogramma species Westwood (Hymenoptera: Trichogrammatidae), egg parasitoids of Erinnyis ello (L.) (Lepidoptera: Sphingidae)

Vieira, Jaci Mendes 13 October 2011 (has links)
Trichogramma demoraesi Nagaraja, 1983, T. manicobai Brun, Moraes e Soares, 1984 e T. marandobai Brun, Moraes e Soares, 1986 têm sido referidos como parasitoides de ovos do mandarová-da-mandioca, Erinnyis ello (L., 1758), em plantações de mandioca no Brasil. Entretanto, com base na a análise comparativa dos caracteres morfológicos do parátipo (macho) de T. demoraesi, depositado no The Natural History Museum, Londres, com os exemplares, obtidos de ovos do mandarová-da-mandioca, identificados anteriormente como T. demoraesi (coleção da ESALQ), verificou-se que esses exemplares não pertencem a T. demoraesi, mas são realmente espécimes de T. marandobai. Portanto, T. demoraesi não parasita ovos de E. ello no Brasil. Assim, apenas T. manicobai e T. marandobai foram caracterizadas e ilustradas detalhadamente, pois as descrições originais dessas espécies são sucintas e não foram adequadamente ilustradas. O processo intervolselar de T. marandobai apresenta variações no ápice (arredondado ou truncado). Entretanto, com base nas análises biológicas (cruzamentos), morfométricas e moleculares, comprovou-se que os espécimes com processo intervolselar truncado ou arredondado são variações intraespecíficas de T. marandobai. / Trichogramma demoraesi Nagaraja, 1983, T. manicobai Brun, Moraes e Soares, 1984 e T. marandobai Brun, Moraes e Soares, 1986 have been reported as egg parasitoids of Erinnyis ello (L.) on cassava in Brazil. However, the comparative analysis of the morphological characters of the paratype (male) of T. demoraesi, deposited at The Natural History Museum, London, with specimens from eggs of Erinnyis ello, previously identified as T. demoraesi (ESALQ collection), indicated, in fact, that these specimens do not belong T. demoraesi, but to T. marandobai. Therefore, T. demoraesi does not parasitize eggs of E. ello in Brazil. Then, only T. manicobai and T. marandobai were characterized and illustrated in detail, because original descriptions for both species are succinct and poorly depicted. The intervolsellar process (blunt or truncated apically) of T. marandobai was found to be plastic. However, based on biological (crossings), morphometric and molecular analyses, it was proved that specimens with blunt or truncated intervolsellar process are intraspecific variations of T. marandobai.
26

Minimization of overall person delay at light rail transit crossings on congested urban arterials

Unknown Date (has links)
This study describes analytical model as one innovative way to simulate Light Rail Transit (LRT) operations and calculate vehicular, transit and person delays at LRT crossings through Microsoft Excel. Analytical model emulates LRT trajectories from field and use these trajectories to clearly define train and car phases through Visual Basic for Applications (VBA) logic, which is part of analytical model. Simulation of train trajectories and calculations of delays were done for different LRT strategies and estimated roadway condition, Testing and validation of analytical model were performed in one case study in Salt Lake City (UT). Results show that analytical model is capable of emulating LRT trajectories and estimating delay at isolated LRT crossing. However, analytical model is not capable of simulating different train strategies at two or more LRT crossings, at the same time. Finally, extracted strategy provides savings from $100.000 to $200.000 in study area, on annual basis for projected year. / by Nikola Mitrovic. / Thesis (M.S.C.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
27

Mule Deer and Wildlife Crossings in Utah, USA

Schwender, Megan 01 May 2013 (has links)
Wildlife-vehicle collisions (WVCs) negatively impact wildlife populations and create dangerous driving situations for motorists. In Utah, USA, mule deer (Odocoileus hemionus) encounter a variety of hazards as they attempt to cross highways and interstates, some of which are 8 lanes wide. Agencies have sought to mitigate the risks posed to drivers and mule deer by building crossing structures for wildlife. The objectives of this study were to evaluate the effectiveness of crossing structures in Utah to safely pass mule deer under highways and to determine the variables that best explain mule deer passage use. From 2008 - 2011 we used 26 camera traps to measure levels of mule deer use of 9 culverts and 4 bridges in Utah. We tested for relationships between mule deer structure use and a variety of structural and landscape attributes at each site, including 2 time variables: time since the structure was built and time each structure was monitored by our camera traps. We also developed and tested a new equation (window ratio) that measured culvert openness to approaching mule deer. In the single variable regression models, mule deer structure use was positively correlated with short culverts and coarse scale shrub cover, and negatively correlated with fine scale grass cover. In the multivariate model, structure use was positively correlated with days monitored and elevation and short culverts. Although the new window ratio did not emerge as the most important predictor for mule deer crossing use, it was more effective at predicting mule deer culvert use than the often referenced openness factor. Our results indicated that 12 of the 13 crossing structures studied effectively facilitate the movement of mule deer in Utah; however some were used far more than others. We suggest that older crossing structures built with the shortest dimensions possible, with attached wildlife-exclusion fencing, and in shrubby habitat will be most effective at passing a high volume of mule deer under Utah highways.
28

Low volume grade crossing treatments for the Oregon high speed rail corridor

Zaworski, David D. 30 April 1996 (has links)
This study defines the information gathering and communication and response needed for safety at highway-rail crossings. It examines technologies for low-cost, high-safety treatments for low volume highway crossings of higher speed (130-200 kph) rail. Crossing closure and consolidation is a necessary first step. Existing train control and crossing safety systems are examined. Intelligent Transportation System technologies are examined for applicability to the information gathering, communicating, and control functions of grade crossing safety. Guidelines are offered for low volume crossings of the high speed rail line in Oregon. A preliminary cost benefit analysis is presented. Above 200kph, crossing closure or grade separation is required. In the range of 130-200 kph, ITS technologies have the potential to enhance crossing safety at much lower cost than grade separation. A global positioning system based positive train control system provides the train location and speed information needed for advanced crossing control. A traffic management center can receive train and crossing information, operate crossing systems, and grant clearance for train or highway users through the crossing. Remote lock gates provide safety at private crossings. Increased traveler information and four quadrant warning gates increase motorist compliance at public crossings. At train speeds above 175 kph, barrier gates protect rail movements. Video monitoring and detection systems provide reliable, redundant information should a vehicle become trapped in a crossing. / Graduation date: 1996
29

Evaluation of the effects of a highway improvement project on Key deer

Braden, Anthony Wayne 30 October 2006 (has links)
Deer-vehicle collisions (DVCs) along a 5.6-km segment of United States Highway 1 (US 1) on Big Pine Key (BPK), Florida responsible for approximately 26% of endangered Florida Key deer (Odocoileus virginianus clavium) annual mortalities. The Florida Department of Transportation (FDOT) constructed a 2.6-km long system of fencing, 2 underpasses, and 4 experimental deer guards to address DVCs along a portion of the US 1 roadway in 2001–2002. I evaluated the effectiveness of the project in reducing Key deer mortality by comparing (1) survival of radio-collared deer, (2) deer-vehicle collisions on US 1, and (3) determining the ability of deer to access the fenced segment. I found no significant difference in male or female survival. Key deer-vehicle collisions were reduced by 83–92% inside the fenced segment. However, overall US 1 Key deer-vehicle collisions did not change. Key deer entry into the fenced segment was minimized to 8 deer during the first-year resulting in 2 deer mortalities. I also assessed the potential impacts of the US 1 corridor project to Key deer movements by comparing (1) radio-collared Key deer annual ranges (2) radio-collared deer corridor movements, and (3) assessing Key deer underpass and corridor use. Female and male ranges and core areas did not change (P > 0.05). Deer movements within the US 1 corridor were comparable pre- (6 of 23 radio-collared deer crossed the corridor) and post-project (4 of 16). Infrared-triggered camera data indicate underpass movements increased over time. Collectively, post-project telemetry and camera data indicates US 1 highway improvements have not restricted Key deer movements. Hourly Key deer movement and US 1 traffic patterns were compared to annual US 1 DVCs. Hourly deer movements showed a positive correlation (P = 0.012, r = 0.505) to hourly DVCs for the full circadian period. Hourly US 1 traffic showed a significant positive relationship (P = 0.012, r = 0.787) with DVCs only during the night period. Evaluation of hourly deer movements and hourly traffic volume on US 1 found hourly DVCs to be the result of a combination between both variables.
30

A microsimulation analysis of highway intersections near highway-railroad grade crossings

Tydlacka, Jonathan Michael 15 November 2004 (has links)
The purpose of this thesis was to perform microsimulation analyses on intersections near Highway-Railroad Grade Crossings (HRGCs) to determine if controlling mean train speed and train speed variability would improve safety and reduce delays. This research focused on three specific areas. First, average vehicle delay was examined, and this delay was compared for seven specific train speed distributions, including existing conditions. Furthermore, each distribution was associated with train detectors that were placed at the distance the fastest train could travel during the given warning time. Second, pedestrian cutoffs were investigated. These cutoffs represented an occasion when the pedestrian phases were truncated or shortened due to railroad signal preemption. Finally, vehicle emissions were analyzed using a modal emissions model. A microscopic simulation model of the Wellborn Corridor in College Station, Texas was created using VISSIM. The model was run twenty times in each train speed distribution for each of three train lengths. Average vehicle delay was collected for three intersections, and delays were compared using the Pooled t-test with a 95% confidence interval. Comparisons were made between the distributions, and generally, distributions with higher mean train speeds were associated with lower average delay, and train length was not a significant factor. Unfortunately, pedestrian cutoffs were not specifically controlled in this project; therefore, no statistical conclusions can be made with respect to the pedestrian cutoff problem. However, example cases were devised to demonstrate how these cutoffs could be avoided. In addition, vehicle emissions were examined using the vehicle data from VISSIM as inputs for CMEM (Comprehensive Modal Emissions Model). For individual vehicles, as power (defined as the product of velocity and acceleration) increased, emissions increased. When comparing emissions from different train speed distributions, few significant differences were found. However, a scenario with no train was tested, and it was shown to have significantly higher emissions than three of the distributions with trains. Ultimately, this thesis shows that average vehicle delay and vehicle emissions could be lowered by specific train speed distributions. Also, work could be done to investigate the pedestrian cutoff problem.

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