Normally the trucks with four wheel drive option will be running in rear wheel drives and the front wheels will be rotating freely. In extreme tough driving conditions, the risk for getting stopped or slipping the rear wheels in mud is high. When the driver tries to engage the four wheel drive option and due to the difference in relative rotational speed of the dog clutch parts, there is a risk for slipping off or bouncing back of the dog clutch. After studying the importance of gear geometry and a few parameters, the team ended up with a new design and the performance of the design found satisfactory when simulated in MSC ADAMS.

Hyundai, Toyota and GM automobile factory were committed to provide more speed planetary gear automatic transmission research and development in order to improve the transmission performance and fuel efficiency. To set embedded clutch into planetary gear mechanism is an effective way to get more speed ratio, its call an epicyclic-type automatic transmission with embedded clutches, referred to the embedded-type automatic transmission. For the development of automatic transmission with eight or more speed ratios, an efficient design methodology is urgently needed and still not available. Therefore, the purpose of this article is to develop a systematic method for the design of automatic transmission with embedded clutches. First, the features and requirements of the automatic transmissions with embedded clutches are investigated and the corresponding design requirements are induced. Next, the theory of the analysis of kinematic for automatic transmissions with embedded clutches is derived based on the concept of lever analogy. Then, the design theory of automatic transmissions with embedded clutches is developed based on the analysis theory. Finally, the complete atlas of automatic transmissions with embedded clutches can be systematically synthesized from the data of given speed ratios. In this article, the innovative and patentable seven-speed and eight-speed automatic transmissions with embedded clutches have been done. This proposed design method can also be applied to the development and design of ten-speed automatic transmissions with embedded clutches.

The salamander family Sirenidae is composed of two extant genera, Siren and Pseudobranchus, each with two known species. Several questions regarding Sirenidae life history persist, and much of the available life history data for Pseudobranchus are attributed to studies of P. axanthus in northern Florida. Information on the reproductive biology of P. axanthus is limited, and historical references often suggest contradictory results. This study was undertaken to clarify information and expand on the limited data regarding P. axanthus reproductive biology, specifically for southern Florida populations. The study population was most likely the P. a. belli subspecies. P. axanthus in southern Florida exhibited year round, continuous reproduction with oviposition documented in nine months. Potential clutch size was positively correlated to female size. The largest observed potential clutch was a female with 58 pre-ovulatory oocytes. The largest observed bout was a female with 15 oviductal eggs. Female P. axanthus in southern Florida oviposited eggs singly and at total densities of 3-4 eggs/m2. Developmental time to egg hatching lasted about 30 days, larvae hatched at 16mm TL, and minimum size at female sexual maturity was 115mm TL and 72mm SVL. The reproductive biology of P. axanthus was distinctly contrasting to other members of the family Sirenidae, S. intermedia and S. lacertina, that occupy the same habitat at the same study location.

As part of a state-funded Gopher Tortoise (Gopherus polyphemus Daudin) translocation project, I monitored actively grazed improved pastures to determine if they could serve as suitable recipient sites for the threatened Gopher Tortoise displaced by human development. For cattle ranches to be considered suitable recipient sites females must be able to acquire sufficient energy to produce a clutch of viable eggs, and sufficiently high quality vegetation must be available to support juvenile recruitment into the population. Vegetation surveys were conducted to determine the composition and percent cover of plant species, especially those containing high amounts of nutrients, specifically nitrogen. Resident and relocated females were radiographed during the 2010 and 2011 nesting seasons for the presence of shelled eggs. I was able to determine clutch size and egg diameter for both relocated and resident gravid females. Mean clutch sizes were not significantly different between years. Resident females had larger mean clutch sizes than relocated females in both years, significantly so in 2011, suggesting a period of stress and adjustment for relocated females. Egg diameters were significantly larger by 2.5 to 4.5 mm in 2010 for relocated and resident females, respectively, compared to 2011. Three females were recaptured in both years and exhibited the same trend of similar clutch sizes between years but significantly smaller eggs in 2011. A total of 68 unique taxa from 31 families were found, grasses (Poaceae) were the most dominant and covered a mean of 57% of the total sampled area. Four forb species occurred at much greater percent covers than all others. However, only two species (Richardia and Desmodium) were found to have adequate nutritional content and occur at percent covers greater than five percent, indicating that forage availability may be high, but forage quality may be inadequate to support growing juveniles. Burrow surveys indicate that at least some hatchlings are able to successfully leave the nest by the presence of hatchling size burrows scattered throughout the fields, but the ratio of juveniles to eggs laid is especially low. Survivorship of eggs, hatchlings and juveniles may be too low to support a sustainable Gopher Tortoise population in improved pasture possibly because of lack of adequate forage, burrow compaction by cows, lack of available natural shelter material for protection from desiccation, and the reduced ability of movement in thick pasture grasses, especially by hatchling and yearling tortoises.

The song thrush (Turdus philomelos) was introduced to New Zealand from Britain during the mid 19th century and has become one of the most common terrestrial bird species in New Zealand. In this study, I surveyed a range of life-history traits in New Zealand song thrushes for comparison with traits of British thrushes. Clutch size, egg size and nest size have decreased, while the nestling period is shorter and the incubation period longer. This combination of changes suggests birds are investing less energy into each reproductive bout. Birds also appear unable to raise large broods, as nestling starvation is common in New Zealand, which suggests that food is limiting. I experimentally tested the ability of song thrushes to incubate enlarged clutches and broods, but productivity was not higher for enlarged broods and natural 3- and 4-egg clutches produced similar numbers of fledglings. Thus reduced clutch size may be an adaptation to the local environment. Differences in female incubation behaviour, with 3- and 4-egg clutches receiving higher levels of incubation and more visits per hour than 5-egg clutches, also suggest New Zealand thrushes have difficulty coping with clutches as large as those in Britain. The decrease in clutch size between New Zealand and Britain is in the direction and magnitude expected based on the change in latitude, which supports the hypothesis that factors affecting foraging time and food availability, such as daylength, temperature and rainfall, may be selecting for smaller clutches. Egg size was also found to have decreased in New Zealand, though this may be the result of smaller adult size. Hatchling mass was related to egg volume, but I found no effect of egg volume or clutch size on hatching success. However, nests containing more pointed eggs (i.e., abnormally-shaped eggs), had lower survival and hatching/fledgling success. Data from the national nest record database and my study both suggest that differences in song thrush productivity are the result of differential survival of nestlings. Nestling mortality due to starvation was common at Kowhai Bush, but rare in Britain, so either adult condition or food availability may be lowering reproductive success in New Zealand. High rates of nest failure (>65%) could also affect clutch size, but the strong directional selection imposed by food limitation during the nestling period suggests that increases in food supply would result in increased reproductive success even with the same levels of nest failure. When comparing clutch size throughout New Zealand, I found a significant, positive relationship with rainfall, which further suggests that food limitation may be the main factor driving changes in life-history traits of song thrushes in New Zealand.

Seit einigen Jahren hat sich Mathcad als universelle Mathematiksoftware an vielen Universitäten, Instituten und in Unternehmen bewährt. An der Professur Maschinenelemente der TU Chemnitz wird Mathcad derzeit u.a. bei der Entwicklung einer vollkommen neuartigen Riemenscheibenkupplung für PKW-Kältemittelverdichter eingesetzt. Hierfür wurde ein mathematisches Modell entwickelt, mit dem sich die Bauteilbelastungen sowie die dynamischen Vorgänge in der Kupplung simulieren lassen. Bei der Analyse und Optimierung solcher technischen Systeme besteht häufig der Wunsch, die Bewegung der Bauteile und die wirkenden Kräfte direkt in Mathcad dreidimensional zu visualisieren, ohne dass dafür ein CAD-System benötigt wird. Im Vortrag werden benutzerfreundliche Funktionen präsentiert und anhand einiger Beispiele live vorgeführt, mit denen dies möglich ist. Des Weiteren wird gezeigt, wie diese Funktionen bei der Entwicklung der genannten Riemenscheibenkupplung eingesetzt wurden.

Typescript. Includes vita and abstract. Bibliography: Includes bibliographical references (leaves 63-68). Description: viii, 68 leaves : map ; 29 cm. / The ability of the Pigeon Guillemot Cepphus columba to rear an additional chick was tested by manipulating clutch sizes. The effect of the manipulations on growth, and hatching, fledging, and egg success was measured in chicks from experimental, natural, and control nests. No significant differences were observed between the nest types. Data from 1983, 1984, 1985, and 1989 were analyzed for potential differences in reproductive success of one and two egg clutches. The ratio of one to two eggs was significantly higher in 1985 and 1989. Hatching and fledging success was significantly higher for two egg clutches in 1985 and 1989. No significant differences were observed for egg success. Egg volume was significantly greater in two egg clutches in 1983 and 1984. Egg volume was correlated with fledging but not with hatching success.

Os revestimentos orgânicos de embreagem são compostos basicamente por matriz orgânica, cargas, lubrificantes sólidos e fibras de reforço. A matriz orgânica possui função estrutural e tem grande influência nas propriedades tribológicas do sistema, isto é, no coeficiente de atrito e taxa de desgaste tanto do material de atrito, quanto do contra-corpo metálico. Baseado nas normas ambientais para indústria automobilística, o presente trabalho estuda a viabilidade de substituir a resina fenólica, utilizada como matriz estrutural na composição de revestimentos de embreagem, por termoplásticos de engenharia especiais. O principal objetivo da substituição é a eliminação do fenol livre no produto final, e conseqüentemente a geração de um refugo classificado, de acordo com a norma NBR 10004, como não perigoso. Plásticos de engenharia especiais apresentam alta temperatura de uso contínuo e manutenção das propriedades mecânicas em altas temperaturas e são, geralmente, empregados em materiais que suportam alta pressão, tais como engrenagens, freios, rolamentos e embreagens. Avaliou-se a influência da velocidade de deslizamento e da carga normal no comportamento tribológico tanto do compósito de resina fenólica (base de comparação) como dos compósitos de resina poli (amida imida) e resina poli (éter éter cetona) quando estes deslizavam a seco em um contra-corpo usinado de ferro fundido cinzento, mesmo material utilizado nas placas de pressão. Foram avaliadas características térmicas e mecânicas dos compósitos, por meio de análises termogravimétricas, dinâmicomecânica e dureza. Após os ensaios tribológicos, as superfícies desgastadas dos corpos poliméricos e dos contra-corpos metálicos foram avaliadas por meio de microscopia ótica, microscopia eletrônica de varredura e composição química. Embora os compósitos de resina PAI e resina PEEK sejam classificados como produtos não perigosos, a substituição não é viável pois, nas condições de velocidade de deslizamento e carga normal estudadas, os compósitos de resina PAI e resina PEEK apresentaram menor resistência ao desgaste em comparação ao compósito de resina fenólica. / Organic clutch friction facings are basicly composed of an organic matrix, fillers, solid lubricants and reinforcing fibers. An organic matrix has a structural function and has a large influence over the tribological properties of the system (coefficient of friction and wear rate in both, friction material as for the metal counterpart). Based on the automotive industry environmental standards, this analysis studies the viability of substituting the phenolic resin, used as the structural matrix in the clutch facing composition by high performance polymers. The principle objective for this substitution is to eliminate the free phenol in the final product and consequently produce a classified non-dangerous waste in accordance to the NBR 10004 norm. High performance polymers have high temperature working resistance when in continuous use and also maintain their mechanical properties and are normally used in products that support high pressures, such as gears, brakes, bearings and clutches. The influence of the sliding speed and the normal load under tribological behaviour was evaluated for phenolic composites (comparative basis) and for poly (amide imide) composites and poly (ether ether ketone) composites when these slip under dry conditions against a grey iron machined counterpart, the same material as used for pressure plates. Thermal and mechanical characteristics of the composites, obtained by thermogravimetric analysis, dynamic-mechanical and hardness were analysed. After the tribological tests the worn surfaces of the composites samples and of the metallic counterparts were evaluated with optical microscopy, electro scanning microscopy and chemical composition. The environmental characteristics of these materials classify both materials as not being dangerous, but under the sliding speed and load studied the PAI and PEEK composites showed lower wear resistance than the phenolic composites.

A biologia reprodutiva dos Amphisbaenia é uma das menos estudadas entre os répteis, havendo na literatura informações sobre o ciclo reprodutivo, dimorfismo sexual e fecundidade de poucas espécies do grupo, além de informações pontuais acerca de oviposturas. A histologia das vias genitais, da mesma forma, foi pouco estudada, tornando difícil uma melhor caracterização dos ciclos de machos e fêmeas. No Brasil são encontradas cerca de um terço das espécie do grupo, distribuídas por regiões com diferentes características macroclimáticas. Este trabalho teve por objetivo caracterizar o ciclo reprodutivo de machos e fêmeas de onze espécies brasileiras da família Amphisbaenidae, com base em dados de dissecção e histologia, e analisá-los comparativamente tendo como referência a filogenia molecular já proposta para as Amphisbaenidae do Brasil. Objetivou-se ainda realizar uma análise preliminar da relação entre os ciclos reprodutivos observados e variações sazonais de temperatura e precipitação. Para tanto, foram analisados espécimes depositados em coleções zoológicas, que tiveram suas gônadas e órgãos urogenitais examinados e medidos. Foram ainda realizadas análises histológicas de ovidutos, testículos, ductos deferentes e rins de espécimes coletados em diferentes meses do ano, para análise de sua morfologia e caracterização dos ciclos espermatogênico, de estocagem de esperma e de atividade do segmento sexual renal. Foram ainda analisados espécimes e lâminas histológicas de duas espécies da família Blanidae e uma da família Trogonophidae, permitindo uma melhor discussão das características observadas tendo como referência a filogenia do grupo. Foram analisados também dados de dimorfismo sexual de tamanho do corpo e de fecundidade. Os machos de quatro espécies de Amphisbaenidae amostradas apresentaram ciclos reprodutivos assazonais, com períodos de repouso não sincrônicos entre os indivíduos. Os machos de outras sete espécies de Amphisbaenia, duas de Blanidae e uma de Trogonophidae apresentaram ciclos sazonais. Todas as sete espécies para as quais o ciclo das fêmeas pôde ser caracterizado são sazonais nesse aspecto. Os ciclos de machos foram comparados quanto à época e duração das fases de espermatogênese, estocagem de esperma e atividade secretora do segmento sexual renal, tendo sido obtidas evidências de relação entre essas características e a filogenia do grupo. As fases reprodutivas das espécies de Amphisbaenia brasileiras são mais extensas em comparação com aquelas observadas em Blanidae e Trogonophidae. Também se obtiveram evidências preliminares da relação entre sazonalidade dos ciclos reprodutivos e variações anuais de temperatura e precipitação. Em sete espécies de Amphisbaenidae, foi observado dimorfismo sexual quanto ao comprimento rostro-cloacal ou ao comprimento da cauda. A fecundidade das fêmeas varia entre um e quatro ovos, na maioria das espécies analisadas, mas pode chegar a sete em Amphisbaena mertensi e nove em Amphisbaena trachura. / The reproductive biology of the Amphisbaenia is one of the less known among reptiles. In the literature, there are information on the reproductive cycle, sexual dimorphism, and clutch size for few species, and scarce data on clutches of eggs. Similarly, the histology of the genital tract was studied in few species, which makes difficult to characterize properly the reproductive cycles of males and females. Almost one third of the species of the group occur in Brazil, in regions with different climates. This study aimed to characterize the reproductive cycle of males and females of eleven Brazilian species of the family Amphisbaenidae, based on the dissection and histological analysis of gonads and genital ducts, and to compare the obtained data with regard to the molecular phylogeny already proposed for the Brazilian species of this family. It also aimed to analyze preliminarily the relation between the observed reproductive cycles and seasonal variations of temperature and precipitation. Specimens from zoological collections were analyzed to examination and measuring of the gonads and urogenital organs. Samples of the oviducts, testis, ductus deferens and kidneys from specimens collected in various months were also analyzed using light microscopy to characterize the cycles of spermatogenesis, sperm storage, and activity of the sexual segment of the kidney. Specimens and histology slides of two Blanidae species and one Trogonophidae species were also analyzed, allowing a better discussion of the characteristics of the reproductive cycles referring to the phylogeny of the group. Sexual size dimorphism and clutch size were also analyzed. The males of four Amphisbaenidae species presented aseasonal reproductive cycles, with testicular recrudescence and rest phases not synchronized among individuals. The males of the other seven Amphisbaenidae species, two Blanidae species and one Trogonophidae species presented seasonal reproductive cycles. The seven species for which the reproductive cycles of females could be characterized are seasonal in this regard. The male reproductive cycles were compared considering seasonality and the length of spermatogenesis, sperm storage and secretory activity of the sex segment of the kidney. Evidence of relation between the reproductive cycle characteristics and the phylogeny of the family Amphisbaenidae was obtained. The reproductive seasons of Brazilian Amphisbaenia are longer than those observed in Blanidae e Trogonophidae. Preliminary evidence on the relation between reproductive cycle seasonality and annual variations of temperature were also obtained. Seven Amphisbaenidae species presented sexual dimorphism in snout-vent length or caudal length. Clutch size varies from one to four eggs in most species, but reaches seven eggs in Amphisbaena mertensi and nine in Amphisbaena trachura.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-11-13T12:52:57Z No. of bitstreams: 2 Dissertação - Tailise Marques Dias - 2015.pdf: 1168693 bytes, checksum: baf8f1add06723394d5cf4cca3be7937 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-11-13T12:55:29Z (GMT) No. of bitstreams: 2 Dissertação - Tailise Marques Dias - 2015.pdf: 1168693 bytes, checksum: baf8f1add06723394d5cf4cca3be7937 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-11-13T12:55:29Z (GMT). No. of bitstreams: 2 Dissertação - Tailise Marques Dias - 2015.pdf: 1168693 bytes, checksum: baf8f1add06723394d5cf4cca3be7937 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-02-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In anurans, acoustic communication is related to many different behaviors, either reproductive or territorial. In this sense, this study investigated the reproduction and the acoustic and territorial behavior of Hypsiboas goianus. The study was performed in the Floresta Nacional de Silvânia, municipality of Silvânia, state of Goiás, Brazil. Firstly, we investigated the use of calling sites, the calling pattern of the males along the night and the within-individual variation of the acoustic parameters along the night. We found a positive relationship between male snout-vent length and their distance from the water. The males emitted more aggressive calls at the early hours of the night and the number of advertisement calls emitted increased in the middle of the night. Besides, the repetition rate and interval between notes varied along the night. Additionally, we investigated the reproductive ecology and the dynamics of the territorial behavior of H. goianus. We found no relationship between the size of the female and clutch size, and also between egg size and number of eggs. Matings were not assortative. We also performed two territoriality experiments, which included manipulation of the distance between males and the placement of intruder males next to an established resident. In both experiments the number of calls emitted was influenced by size, and physical combat was rare. The results from this study show that male H. goianus maintain a reproductive strategy along the night and that, for this species, acoustic communication is greatly important in different social contexts. / Em anuros, a comunicação acústica é a comunicação primária e está envolvida em diferentes comportamentos, sejam eles reprodutivos ou territoriais. Nesse sentido, este trabalho investigou a reprodução e o comportamento acústico e territorial de Hypsiboas goianus. O estudo foi realizado na Floresta Nacional de Silvânia, município de Silvânia, estado de Goiás, Brasil. Primeiramente, nós investigamos o uso do sítio de vocalização, o padrão de vocalização dos machos ao longo da noite e a variação intraindividual dos parâmetros acústicos ao longo da noite. Nós encontramos uma relação positiva entre o comprimento rostro-cloacal dos machos e a distância deles até a água. Os machos emitiram mais cantos agressivos no início da noite e o número de cantos de anúncio emitidos aumentaram no meio da noite. Além disso, os parâmetros acústicos taxa de repetição e intervalo entre as notas variaram ao longo da noite. Adicionalmente, nós investigamos a ecologia reprodutiva e a dinâmica do comportamento territorial de H. goianus. Nós não encontramos relação entre o tamanho da fêmea e o tamanho da desova, e entre o tamanho dos ovos e o número de ovos. Ainda, os acasalamentos não foram assortativos. Além disso, nós realizamos dois experimentos de territorialidade, os quais incluíram manipulação de distância entre os machos e introdução de machos na área do macho residente. Em ambos experimentos o número de cantos emitidos pelos machos foi influenciado pelos seus tamanhos e os combates físicos foram raros. Os resultados encontrados neste trabalho mostram que os machos de H. goianus mantêm uma estratégia reprodutiva ao longo da noite e que a comunicação acústica é muito importante em diferentes contextos sociais para essa espécie.