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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.
351

Calibration and Estimation of Dog Teeth Positions in Synchronizers for Minimizing Noise and Wear during Gear Shifting / Kalibrering och uppskattning av positioner för dog-teeth i synkroniserare för minimering av buller och slitage under växling

Kong, Qianyin January 2020 (has links)
Electric motors are used more widely in automotive to reducing emissions in vehicles. Due to the decreased usage of internal combustion engines which used to be the main noise source, impacts from synchronizers cannot be ignored during gear shifting, not only causing noise and wear but also delaying gear shifting completion.  To minimize the impacts during gear shifting, a dog teeth position sensor is required but the high calculation frequency leads to a high cost, due to the high velocity of synchronizer portions and the dog teeth number.  In this thesis, the gear shifting transmission is being modelled, in order to study the process of gear shifting and engagement. The transmission model, which is expressed with electrics and dynamics formulations. In order to avoid the impact without the dog teeth position sensor, this thesis proposes an estimation algorithm based on the transmission model to approve the gear engagement if the first and second portions of synchronizers are engaged in the mating position without impacts.  Two different learning algorithms: direct comparison and particle swarm optimization application, are presented in the thesis as well, which are used to calibrate a parameter in the off-time test as part of the end of the calibration line, the so-called relevant initial phase being used in the real-time estimation.  The transmission model is simulated in Simulink and different algorithms are running in MATLAB. All these results are plotted and analyzed for further evaluation in different aspects in the result chapter. The direct comparison algorithm has a simpler structure of computation but the quantity of required actuation is uncertain in this algorithm with a probability of failure to find the solution. The application of particle swarm optimization in this case succeeds in calibrating the objective parameter with a small error than the other algorithm. Actuation quantity affects the accuracy of the solutions and errors but not the failure rate. / Elektriska motorer används i allt större utsträckning inom fordonsindustrin för att minska utsläppen från fordon. Den minskade användningen av förbränningsmotorer, som tidigare varit den främsta bullerkällan, gör att kollisioner från synkroniserare inte kan bli ignorerade under växlingen. Dessa kollisioner orsakar inte bara buller och nötningar utan även fördröjer slutförandet av växlingen.  För att minimera kollisioner under växlingen krävs det en positionssensor för dog-teeth, men den höga beräkningsfrekvensen leder till hög kostnad på grund av den höga hastigheten hos synkroniseringsdelarna samt antalet dog-teeth.  I den här avhandlingen görs en modell av växellåda för att studera växlingsprocessen och kugghjulsingreppet. Transmissionsmodellen uttrycks med elektriska och dynamiska formuleringar. För att undvika kollisioner utan positionssensor för dog-teeth, föreslås det en uppskattningsalgoritm baserad på transmissionsmodellen för att godta kugghjulsingreppet om den första and andra delen av synkroniseraren är inkopplade i parningsläget utan kollisioner.  Två olika inlärningsalgoritmer, direkt jämförelsemetoden och partikelsvärmoptimeringsmetoden presenteras även i avhandlingen. De används för att kalibrera en parameter i off-time test som en del av slutet av produktionslinjen. Denna parameter kallas för den relevanta initialfasen och används vid realtidsuppskattningen.  Transmissionsmodellen är simulerad i Simulink och de olika algoritmerna exekveras i Matlab. Alla resultat är plottade och analyserade för vidare utvärdering av olika aspekter i resultatkapitlet. Den direkta jämförelsealgoritmen har en enklare beräkningsstruktur, men mängden av nödvändig exekveringar är oklar för denna algoritm med en sannolikhet att det inte går att hitta lösningen. Däremot visar det sig att partikelsvärmoptimeringsmetoden lyckas med att kalibrera målparametern med dessutom ge mindre fel än den andra algoritmen. Antalet exekveringar påverkar lösningen samt noggrannheten hos lösningarna men påverkar inte själva felfrekvensen.
352

Anthropogenic threats to resident and dispersing African wild dogs west and south of the Kruger National Park, South Africa / Antropogenic threats to resident and dispersing African wild dogs west and south of the Kruger National Park, South Africa

Watermeyer, Jessica Patricia January 2012 (has links)
African wild dog Lycaon pictus populations are declining and the species is listed as Endangered by the IUCN. The Kruger National Park (KNP) is home to the only viable population of wild dogs in South Africa, but census results reveal consistently low numbers since the late 1990s. Wild dogs display wide-ranging behaviour and it is possible that the species might frequently use unprotected lands adjacent to the KNP. However, very little is known about wild dog movements beyond the boundaries of the KNP, and whether or not adjacent land owners are tolerant of the species. Significantly, threats along the boundaries may have negative consequences for the KNP population. This research investigated the dispersal habits of wild dogs beyond the western and southern boundaries of the KNP, and gathered information on human tolerance, and anthropogenic threats in an area of mixed land use. The land west of the KNP presented the best prospect for wild dog range expansion. The wild dog packs operating outside the KNP had smaller home ranges and less home range overlap than the packs operating within the KNP. In addition, my data suggested that the development of conservancies and the formation of ecotourism-based land use practices would be beneficial for wild dog conservation. Failed wild dog dispersals due to snaring and human persecution could threaten the genetic stability and persistence of the KNP population. Therefore, raising awareness and an understanding of the plight of wild dogs is important for improving land owner perception and tolerance outside of protected areas. The rapidly increasing human population continues to infringe on protected lands and fragment landscapes, thus cooperation from individual land owners is vital for the conservation of free-ranging large carnivores.
353

Hunden som specialpedagogiskt verktyg i förskolan : Hunden som dörröppnare / The dog as a special educational needs resource for learning.

Ranta, Birgitta, Öyen, Mia January 2018 (has links)
Studiens syfte utgår ifrån hur hunden kan vara till stöd för att motivera barns lust till lärande, synliggöra skillnader mellan utbildningar, samt lyfta fram hur utbildning kring HAP ser ut för hundekipage. Studien har en kvalitativ ansats med motivationsteorier som utgångspunkt i bearbetning och analys av resultat. Den valda metoden har utgått från halvstrukturerade intervjuer som har genomförts med tre hundekipageutbildare och tre hundförare i Mellansverige. Baserat på tidigare forskning, motivationsteori och studiens resultat kan vi påvisa att hunden i prestations- och inlärningssituationer påverkar främst motivation och tro på den egna självförmågan. Både resultat och tidigare forskning påvisar dessutom att HAP kan bidra till bättre skolklimat där lärande blir till något lustfyllt. Det i sig påverkar barnets inre och yttre motivation att lära sig nya och svårare saker vilket i förlängningen leder till ökad måluppfyllelse. Vi kan även se utifrån resultatet att HAP bidrar till att barn utvecklar sina färdigheter inom kommunikation, samspel och motorik, när barnet rör sig och leker tillsammans med hunden. Med andra ord påvisas bättre arbetsförmåga och högre prestationsförmåga i närvaron av en hund.  Forskning som vi använt oss av har främst riktat sig mot skolan. Dock är vår rådande uppfattning att detta koncept är användbart också i förskolan. Utifrån resultatet kan vi se att HAP med stor sannolikhet skulle kunna bidra till att barn utvecklar sina färdigheter och förmågor inom kommunikation, samspel och motorik i förskolan. Även om förskolans undervisning inte nödvändigtvis fokuserar på att mäta kunskaper som skolan gör, så finns det utrymme att hävda att hunden kan vara till hjälp också inom ramen för förskolans lärområden.
354

The feasibility of reintroducing African wild dogs (Lycaon pictus) into the Great Fish River Nature Reserve, Eastern Cape, South Africa

Page, Samantha Karin January 2014 (has links)
With a declining population of roughly 3000-5000 individuals in Africa, African wild dogs (Lycaon pictus) are one of the most endangered carnivores in the world. As the global human population expands, it is becoming increasingly unlikely that large portions of land will be set aside for conservation, especially in developing countries. Thus, recent wild dog conservation efforts in South Africa have concentrated on establishing a managed metapopulation. A metapopulation is a group of geographically isolated subpopulations of a species that are managed (using supplementation and harvesting) to mimic natural gene flow. The Great Fish River Nature Reserve (GFRNR) in the Eastern Cape Province of South Africa has been identified as a potential reserve to become part of the national wild dog metapopulation. My research aimed to conduct a feasibility assessment of the long-term (~ 25 years) success of a wild dog reintroduction into the GFRNR. This assessment included biological modelling of wild dogs and their expected prey, and determining the potential anthropogenic threats to wild dogs on the private and communal land surrounding the reserve. I used VORTEX population modelling and determined that the GFRNR is likely to have a wild dog carrying capacity of ~22 individuals. Using a 25-year modelling simulation, the most appropriate wild dog reintroduction scenario would be to reintroduce six females and four males initially and supplement the population with one female and two males in years 3, 10, 15 and 23. In addition, the harvesting/removal of one male and one female in years 10 and 20 would be required to ensure 100% population persistence and adequate genetic diversity. Kudu (Tragelaphus strepsiceros) and bushbuck (Tragelaphus scriptus) are expected to be the two most important prey species for reintroduced wild dogs in the GFRNR. Furthermore, wild dogs are likely to prefer the north-western and south-western sectors of the reserve because of the relatively high prey densities in these areas. However, regular monitoring of both the potential prey and the wild dog populations is essential to ensure persistence of the wild dogs and to prevent prey populations decreasing precipitously. Using structured questionnaire interviews (n = 128), I found that while neighbouring land owners and local communities were generally positive about the potential wild dog reintroduction (56 % of all respondents), several threats to wild dogs were identified along the reserve boundary and on the adjoining unprotected land. Some private landowners and members of rural communities around the reserve (34 %) stated that they would kill any wild dogs that dispersed onto their land. In addition, some respondents (8 %) admitted to believing in traditional uses for wild dog products (e.g. fur) which could result in the illegal killing of wild dogs outside of the GFRNR for traditional purposes. Poaching and the presence of unvaccinated domestic dogs on neighbouring land were also identified as being potential threats to a reintroduced wild dog population. However, such anthropogenic threats appear to be localised to the western and southern boundaries of the reserve. Therefore, by implementing preventative measures (such as anti-snare collars, anti-poaching patrols and vaccination against rabies and canine distemper) the likelihood of such threats occurring can be reduced. I conclude that the GFRNR can sustain a population of wild dogs and successfully contribute to South Africa‘s national metapopulation. An additional reserve will benefit the country‘s metapopulation by increasing the number of wild dogs available for translocation, thereby increasing genetic diversity and overall resilience (to environmental change, disease etc.) of South Africa‘s wild dog population. This will contribute towards the future conservation of this endangered species.
355

Očima psa - dětská autorská kniha / Through The Eyes of a Dog - Authors children book

Richterová, Denisa January 2021 (has links)
RICHTEROVÁ, Denisa: Through the Eyes of a Dog - Author's Book for Children. Prague, 2021. Diploma thesis. Charles University, Faculty of Education, Department of Art Education. (Appendix 1: author's book for children The Dog Who Thinks Something) (Appendix 2: presentation of the project Through the Eyes of a Dog) This diploma thesis deals with a dog as a bearer of contemporary historical and cultural contexts. The theoretical part describes the history of the domestication of dogs, their relationship to humans, symbolism and mythology, and maps the associated depiction in the history of fine art. Attention is then focused on the relationship between dogs and kids with an overlap into children's literature and on illustrations with emphasis on author's book for children. Finally, there is a devotion to the representation of dogs in assisting with the educational and therapeutic processes. In the practical part theoretical knowledge is applied in the form of a author's book for children called The Dog Who Thinks Something. The story and illustrations reflect the world through the eyes of a dog which mirrors thinking, feeling and the natural need to belong to someone. The didactic part presents a project called Through the Eyes of a Dog, which submits options of how the dog is connected with free time...
356

Arkeologihund : En studie i experimentell arkeologi om möjligheten att använda hund som arkeologisk prospekteringsmetod för att lokalisera humanosteologiskt material. / Archaeology dog : an experimental archaeology study on the possibility of using a dog as an archaeological prospection method to locate human bones.

Vallulv, Sophie January 2015 (has links)
In today’s archaeology there’s a growing need for non-invasive prospection methods. However there’s a methodological gap and what’s missing is a method for locating human bones. In this study a specially trained German shepherd is put through scientific tests determining how good the dog is at telling the different between the scent of human and animal bones. The dog is also tested in an outdoor environment to simulate an actual archaeological site. The tests in this study show that the dog can distinguish between the smell of human and animal bones with an accuracy of 94,2 % and that he can detect human bones in the field. Further tests need to be conducted to calibrate the method.
357

Paws for Progress : the development and evaluation of the first prison based dog training programme in the UK

Leonardi, Rebecca Jean January 2016 (has links)
The most common type of human animal interaction (HAI) programme used in prisons involves prisoners caring for and training unwanted dogs from rescue shelters, to prepare the dogs for rehoming. Such programmes have been previously developed specifically aimed towards male young offenders, and are claimed to improve emotional, social and practical outcomes. Paws for Progress, the first prison based dog training programme in the UK, was introduced to HM YOI Polmont in 2011. By clearly communicating each step of the 5 Step approach (1. Identify the problem; 2. Review the evidence; 3. Develop a logic model; 4. Identify indicators and monitor the logic model; 5. Evaluate the logic model), it has enhanced our understanding of the development processes required for effective prison based dog training programmes. This evaluation provides the first comprehensive quantitative analysis of short, medium and long term outcomes for Scottish young offenders serving custodial sentences (N = 70) following participation. The aims of Paws for Progress are to improve behaviour, increase engagement in education, develop employability skills, and enhance well-being. Using a mixed design with two control groups and triangulating quantitative and qualitative outcomes, the evaluation assesses the efficacy of the programme in meeting these aims. Systematic analyses of semi-structured interviews pre and post participation in the programme support findings from the quantitative analyses. Analyses of institutional behaviour, measured by Disciplinary Reports, educational progress measured by written assessments and qualifications, employability skills measured by psychometric tests, and prisoner well-being all improved for participants, but such improvements were not shown by control groups. Paws for Progress positively impacts short and medium term outcomes and data on longer term outcomes also indicate the benefits are far reaching. By clearly relating programme aims to the outcomes achieved, and considering the contribution of Paws for Progress to future desistance from crime, the value and relevance of these findings are evident. The evaluation contributes to our understanding of effective methodologies in this applied context, which can be utilised to improve research practice in interventions in criminal justice and in human animal interaction.
358

Porovnání výkonnosti potomstva německého ovčáka po domácích a zahraničních plemenících

FEIKOVÁ, Klára January 2017 (has links)
This graduation thesis deals with comparison of performance of progeny of German shepherd the national and foreign stud dogs. The literary overview follows the history and current form of the International Examination Rules, breeding of German shepherds in the Czech Republic and on global level. It describes complete characteristics of a German shepherd, like the physique, body measurements, living demands and then it is engaged in influences affecting the sport performance of dogs, breeding conditions and it follows the most frequent health problems in German shepherds breeding. The core of the thesis includes analyses of performance of gets of national and foreign stud dogs in the position of a father or father's father in selective competitions, Czech Republic Championships IPO and Championships of the Czech Club of German Shepherds (M ČKNO). There were monitored the data on numbers of individuals in specified competitions in monitored periods of the years 2009 2016. More, dogs placed on 1st up to 10th positions at MČR IPO and M ČKNO were assessed from the point of view of fathers and grandfathers. On the basis of detailed monitoring and analysis it was detected that that dogs from foreign stud dogs origin whether in father's or grandfather's positions are more frequently used in sport cynology. There were 58% of participating dogs from foreign stud dogs and only 42% of dogs with fathers of Czech origin participating in selective competitions. It was established that 61% of participating dogs from foreign stud dogs and 39% of dogs with fathers of Czech origin participated in MČR IPO. The stud dogs of dogs participating in ČKNO Championship were of 68 % of foreign origin and 32 % of nationals. In the course of more detailed analysis (assessment of dogs taking up to 10th position in MČR IPO and M ČKNO) it was established that 67,9% respectively 61,25% of the most successful sport dogs have fathers from foreign kennels, while only 32,1% respectively 38,75 % are from stud dogs from Czech kennels. The best stud dogs from abroad were Ellute von der Mohenwiese and Tom van't Leefdaalhof. Jaguar Aritar Bastet and Hoky Va Pe belonged to the best national stud dogs.
359

Papel da angiotensina II e das prostaglandinas no mecanismo de regulação da função renal de cães após ingestão de uma carga de proteína

Covizzi, Gabriela Jayme [UNESP] 19 January 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-01-19Bitstream added on 2014-06-13T19:20:15Z : No. of bitstreams: 1 covizzi_gj_dr_jabo.pdf: 864511 bytes, checksum: 486b6b2592415ef19352604b7366b859 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A ingestão de proteína promove modificações na função renal. O mecanismo que governa este evento ainda não é conhecido. O estudo foi composto por seis experimentos realizados com os mesmos animais. Inicialmente (capítulo 2) foi conduzida a avaliação basal e investigação das modificações da fisiologia renal determinadas pela carga de proteína (CP). No capítulo 3, foi estudada a participação das prostaglandinas na regulação das funções glomerular e tubular por meio do uso de antiinflamatório não-esteroidal, em condição basal e com CP. Do mesmo modo, o capítulo 4 destinou-se a estudar a relação do Sistema Renina Angiotensina Aldosterona (SRAA) sobre a função renal e sua possível interação com a resposta dos rins à CP. Assim foram utilizados o inibidor da ECA (i-ECA), e a combinação de CP+i-ECA. Os experimentos permitiram concluir que cães sadios alimentados com uma carga de proteína equivalente à necessidade diária, respondem com aumento importante da taxa de filtração glomerular (TFG). As prostaglandinas participam do mecanismo de manutenção renal da homeostase de água, sódio e potássio continuamente e, atuam no mecanismo que aumenta a filtração glomerular após CP. Por outro lado, a angiotensina II (AII) pode ser responsável pela manutenção da TFG em situação basal, ou seja, quando o aumento da filtração não é requerido. Se fisiologicamente o cão apresenta aumento da TFG após ingestão de proteína, e este evento fica parcialmente restringido com a inibição da formação de AII, o aumento de liberação de renina pode desencadear diminuição não fisiológica da TFG. Assim, há indicativos de que o SRAA e as postaglandinas trabalham de maneira contrabalanceada para manutenção da TFG, e a conservação destes mecanismos é essencial para a homeostase renal. / The ingestion of protein promotes modifications in renal function but its mechanism is still unknown. The present study was based on six experimental essays using the same animals. Initially, there was a basal evaluation and also an investigation of modifications in renal physiology due to load protein (chapter 2). In chapter 3, it was studied the action of prostaglandin upon regulation of glomerular and tubular function through the use of nonsteroidal anti-inflamatory drugs (basal and load protein). The relation of the renin angiotensin aldosterone system on renal function and its possible interaction with kidneys response to load protein was studied in chapter 4. For that purpose it was used ECA inhibitor (i-ECA), and the combination of load protein + i-ECA. The experiments allow us to conclude that healthy dogs fed with load protein equivalent to diary ingestion, presented a remarkable increase in GFR. Prostaglandins participate continuously of renal mechanism of water, sodium and potassium homeostasis and act in the mechanism that increases glomerular filtration after load protein. On the other hand, angiotensin II (AII) may be responsible for the maintenance of GFR when the increase of filtration is not required (basal). If the dog presents increase in GFR after protein ingestion and this event remains partially restricted with the inhibition of AII formation, the increase in renin release may promote a non-physiological diminution of GFR. Thus, there are indicatives that the renin angiotensin aldosterone system and the prostaglandins act in a counterbalanced way to maintain the GFR and the preservation of these mechanisms are essential for renal homeostasis.
360

Povědomí žáků 1. a 2. tříd 1. stupně základních škol o etologii psů / Students of 1st and 2nd class of basic school - awareness of dog ethology.

PETŘÍKOVÁ, Šárka January 2011 (has links)
ABSTRACT Nowadays, more and more often we hear about children who are attacked by dogs. The media constantly inform us about fighting breeds and their attacks on humans. Number of dogs in the household significantly increases and posibility of injury of the child by our four-legged partner is increasing too. This situation requires a solution. Media accused of assaulting an animal, unfortunately very often the culprit is not even a dog or child. Thesis on ?The awareness of pupils of first and second class ofthe first level of basic schools on the ethology of dogs ? is based on the author's practical experience with objective reality. The author herself, which is devoted to dogs more than 15 years, also tried to capture the degree of knowledge of school age children on the natural behavior of our four-legged domestic ?pets?. Through her own research, conducted by standardized questionnaires at selected basic schools in the South Bohemia region (in total 284 respondents) reveals the primary mistakes committed by these children in contact with their own or strange dog. The theoretical part is devoted to common cohabitation of children (or people) and dogs. Various chapters are focused on the historical evolution of domestic dog, the coexistence of humans and dogs, and communication sinals, which they use to interact among themselvest, but also on the impact of a dog on the psyche of the child. The research revealed significant gaps in knowledge regarding children's innate behavior of the dog. For this reason children can not adequately respond to a signal that is sent by a dog, so there can arise a hazardous situation between them. At the end of thesis the author proposes a practical solution that could serve as a basic for a new educational program aimed at preventiv injuries caused by dogs attack the children.

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