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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.
11

Desenvolvimento de ferramenta computacional para obtenção automática de deslocamento e anotação de outros parâmetros em testes comportamentais do tipo campo aberto / Development of software to automatically obtain displacement and annotation of other parameters in open field behavioral tests

Oliveira, Isabela Maria de 10 August 2018 (has links)
Testes comportamentais do tipo Campo Aberto figuram dentre os mais básicos e consolidados para estudos de comportamento animal, sendo, portanto, amplamente utilizados em pesquisas de Neurociência e Farmacologia. Através dele se pode avaliar os efeitos da imposição de diferentes condições no comportamento de animais, bem como comparar ou caracterizar perfis típicos de comportamento entre linhagens de uma mesma espécie. Consistindo de soltar animal em uma caixa e observar, dentre outros parâmetros, seu deslocamento e preferência em permanecer nas áreas próximas às paredes ou nas centrais, a extração desses dados pela forma tradicional acabar por ser limitante à obtenção plena de resultados. Isso posto, este trabalho visa oferecer aos pesquisadores um meio para obter os dados de maneira automatizada, sem o desgaste de ficar assistindo o vídeo do teste para anotar o deslocamento. Escrita em Python, utilizando técnicas consolidadas de Visão Computacional e operações de compreensão acessível, esta ferramenta além de ser Open Source pode ser ajustada à extração de outros parâmetros e à aplicação em outras modalidades do teste, além de oferecer a medida do deslocamento de forma mais precisa. / Open Field Test is a basic and consolidated test used in Animal Behavior studies, especially Neuroscience and Pharmacology. Through it, its possible to evaluate the effects in behavior of imposing different conditions, as well to compare or characterize typical behavior profiles between lineages of the same species. Consisting of releasing an animal in a box and observing, among other parameters, its displacement and preference in remaining in the areas near the walls or in the central ones, the extraction of these data in the traditional way ends up being limiting to obtaining full results. That said, this essay aims to offer researchers a way to get the data in an automated way, without need watching the video of the test to note the displacement. Written in Python, using consolidated techniques of Computational Vision and operations of accessible comprehension, this tool besides being Open Source can be adjusted to the extraction of other parameters and application in other modalities of the test, besides offer a more accurate measure of displacement.
12

Foraging and exploratory behaviour in Red Junglefowl (<em>Gallus gallus</em>) selected for fear of humans

Walett, Emma January 2010 (has links)
<p>Domestication is a process in which animals become adapted to a life among humans by means of selection. A reduced fear of humans is probably one of the first aims of selection, intentionally or unintentionally. Animals that have undergone the process of domestication have a different appearance than animals in the wild (domestic phenotype) and behave in a different way towards humans. In this study I have looked at foraging and explorative behaviours in an unselected parental generation of red junglefowl and their offspring. The parental generation were bred in three lines, a high line, with birds displaying a strong fear of humans, an intermediate line, birds showing a modest fear, and one low line, with birds performing a more tame behaviour towards humans. I presented the birds with three different feeding alternatives, familiar chicken food, meal worms camouflaged with wood shavings and just wood shavings. I counted number of pecks in the different food options, number of changes between sites and how many sites a bird visited. The results show that females of both generations were more explorative than males, by pecking more in cups of meal worms hidden in wood shavings whereas the males pecked more in cups containing chicken food. Females also moved around more in the arena. Results from the first selected generation show significant differences between the selection lines among the females, with females from the high and low groups being the most explorative.</p>
13

Database and Modeling of Field Test Data fromLithium Ion Batteries in Hybrid Electrical Vehicles.

Höök, Niclas January 2011 (has links)
In this thesis information received from a hybrid vehicle battery test equipment wasstructured and analyzed. This test equipment is currently placed on a fleet of Scaniatrucks with the purpose of emulating hybrid vehicle environment on battery cell level.A Microsoft Access database structure was set up in order to make it possible to savetest data in a structured way. In addition, Matlab scripts were made with the purposeof calculating cell aging from pulse- and capacity tests. Furthermore, drive cycleanalysis was performed looking at statistics for selected parameters. Data collectedfrom late October 2010 until beginning of July does not yet show any aging of the fieldtested battery cells regarding capacity loss or resistance increase. The internalresistance of the batteries was calculated to 2 to 4 milli ohm and the capacity wasfrom the tests found to be around 3 ampere hours. The energy efficiency, which wascalculated from pulse test data, shows an efficiency between 95 to 97%.
14

Foraging and exploratory behaviour in Red Junglefowl (Gallus gallus) selected for fear of humans

Walett, Emma January 2010 (has links)
Domestication is a process in which animals become adapted to a life among humans by means of selection. A reduced fear of humans is probably one of the first aims of selection, intentionally or unintentionally. Animals that have undergone the process of domestication have a different appearance than animals in the wild (domestic phenotype) and behave in a different way towards humans. In this study I have looked at foraging and explorative behaviours in an unselected parental generation of red junglefowl and their offspring. The parental generation were bred in three lines, a high line, with birds displaying a strong fear of humans, an intermediate line, birds showing a modest fear, and one low line, with birds performing a more tame behaviour towards humans. I presented the birds with three different feeding alternatives, familiar chicken food, meal worms camouflaged with wood shavings and just wood shavings. I counted number of pecks in the different food options, number of changes between sites and how many sites a bird visited. The results show that females of both generations were more explorative than males, by pecking more in cups of meal worms hidden in wood shavings whereas the males pecked more in cups containing chicken food. Females also moved around more in the arena. Results from the first selected generation show significant differences between the selection lines among the females, with females from the high and low groups being the most explorative.
15

Mixing Processes for Ground Improvement by Deep Mixing

Larsson, Stefan January 2003 (has links)
<p>The thesis is dealing with mixing processes havingapplication to ground improvement by deep mixing. The mainobjectives of the thesis is to make a contribution to knowledgeof the basic mechanisms in mixing binding agents into soil andimprove the knowledge concerning factors that influence theuniformity of stabilised soil.</p><p>A great part of the work consists of a literature surveywith particular emphasis on literature on the processindustries. This review forms a basis for a profounddescription and discussion of the mixing process and factorsaffecting the process in connection with deep mixingmethods.</p><p>The thesis presents a method for a simple field test for thestudy of influential factors in the mixing process. A number offactors in the installation process of lime-cement columns havebeen studied in two field tests using statistical multifactorexperiment design. The effects of retrieval rate, number ofmixing blades, rotation speed, air pressure in the storagetank, and diameter of the binder outlet on the stabilisationeffect and the coefficient of variation determined byhand-operated penetrometer tests for excavated lime-cementcolumns, were studied.</p><p>The literature review, the description of the mixingprocess, and the results from the field tests provide a morebalanced picture of the mixing process and are expected to beuseful in connection to ground improvement projects and thedevelopment of mixing equipments.</p><p>The concept of sufficient mixture quality, i.e. theinteraction between the mixing process and the mechanicalsystem, is discussed in the last section. By means ofgeostatistical methods, the analysis considers thevolume-variability relationship with reference to strengthproperties. According to the analysis, the design values forstrength properties depends on the mechanical system, the scaleof scrutiny, the spatial correlation structure, and the conceptof safety, i.e. the concept of sufficient mixture quality isproblem specific.</p><p><b>Key words:</b>Deep Mixing, Lime cement columns, Mixingmechanisms, Mixture quality, Field test, ANOVA, Variancereduction.</p>
16

ZigBee in Industry

Wettergren, Andreas January 2007 (has links)
<p>Den här C-uppsatsens mål är att undersöka om den trådlösa tekniken ZigBee är lämplig att använda i en industriell miljö. Arbetet med uppsatsen har utförts i Trolhättan (Sverige) i företaget Binar Elektronik AB:s lokaler. Bakgrunden till detta samarbete är att Binar vill veta om ZigBee är ett lämpligt val för en av deras framtida produkter.</p><p>Uppsatsen är uppdelad i fyra delar, där den första och inledande delen översiktligt beskriver begreppet ZigBee. Den här delen innehåller även en marknadsundersökning rörande ZigBee-hårdvara. Uppsatsen fortsätter sedan med nästa del där en specialisering mot en specifik ZigBee-hårdvara tar vid. Den ZigBee-modul som valdes kallas Xbee och den blev utvald baserat på resultatet från marknadsundersökningen. Den här delen beskriver även den kod som utvecklats för att på ett effektivt sätt kommunicera med Xbee-modulen.</p><p>Uppsatsens tredje del består av ett antal praktiska tester i olika miljöer, vars mål är att påvisa vilka styrkor och svagheter som ZigBee-tekniken har i respektive miljö. Den här delen innehåller även ett räckviddstest av Xbee-modulen. Den sista och avslutande delen innehåller uppsatsens resultat och slutsatser. Dessa slutsatser visar tydlig att Xbee-modulen, och dess ZigBee-tekniken, har stor potential att uppfylla de krav som ställs på ett trådlöst system i en industriell miljö. Det måste dock noteras att denna slutsats ej bör tas ur sitt sammanhang och att den således endast är giltig för de testmiljöer som den här uppsatsen behandlat.</p> / <p>This Bachelor of Science thesis has the primary objective to investigate whether or not the wireless technology ZigBee is suitable for industry usage. The thesis work has been done in collaboration with Binar Elektronik AB (Trollhättan, Sweden). The background story for this collaboration is that Binar is interested in finding out if ZigBee is suitable for one of their upcoming products.</p><p>The thesis is divided into four main parts, beginning with a researching part concerning ZigBee as a concept and a market research on ZigBee hardware. The thesis continuous with a specialization towards one ZigBee hardware, the ZigBee module from MaxStream called Xbee. The Xbee module was chosen based on the result from the market research. This part also describes the code that has been developed for the Xbee module, which main purpose is to simplify communication with the module.</p><p>The next part of the thesis contains a number of different field tests that show how ZigBee communication is affected in different environments. This part also includes a range test with the Xbee module. The last part of the thesis contains the final results and conclusions, which clearly show that the ZigBee technology, and Xbee in particular, has a potential to satisfy the requirements for a wireless system in an industrial environment. This conclusion concerning the industrial usability of ZigBee should however be seen in the light of this particular thesis work, making this conclusion viable only for the field test environments.</p> / See hompage http://www.wettergren.se/zigbee/.
17

Effekten av olika stressorer på open-field beteende hos kycklingar av White Leghorn

Berlin, Karin January 2012 (has links)
Stress affects a number of animals and is a survival mechanism. During stress, changes in the animal’s physiological mechanisms and changes in behavioural reactions will happen. This study evaluates four different stressors that can occur in a chicken’s life. The four stressors are fixation, social isolation, predation and transport. 40 White Leghorn chicken from age sex to seven weeks were used in the study. An open-field test was used to evaluate the stressors. The open-field test registered time for ambulation, time for first change of zones, number of zones used and number of registrations in central zones. The chicken was expected to ambulate in the open-field arena since chickens are curious but the activity was expected to be different depending on which stressor the chicken was exposed to. Previous studies have shown that more stressed birds are less active in an open-field test than birds that are not stressed. A control group was included in the study and this group was not exposed to a stressor. The results did not show any significant dereferences between time for the first change of zones, number of zones used and number of registrations in central zones. However, there was a tendency for a significant difference in time to first ambulation. The results suggested that the control group and the group that was exposed to social isolation displayed most stress-related behaviour. Least stressed was the predation group and the transport group.
18

Mixing Processes for Ground Improvement by Deep Mixing

Larsson, Stefan January 2003 (has links)
The thesis is dealing with mixing processes havingapplication to ground improvement by deep mixing. The mainobjectives of the thesis is to make a contribution to knowledgeof the basic mechanisms in mixing binding agents into soil andimprove the knowledge concerning factors that influence theuniformity of stabilised soil. A great part of the work consists of a literature surveywith particular emphasis on literature on the processindustries. This review forms a basis for a profounddescription and discussion of the mixing process and factorsaffecting the process in connection with deep mixingmethods. The thesis presents a method for a simple field test for thestudy of influential factors in the mixing process. A number offactors in the installation process of lime-cement columns havebeen studied in two field tests using statistical multifactorexperiment design. The effects of retrieval rate, number ofmixing blades, rotation speed, air pressure in the storagetank, and diameter of the binder outlet on the stabilisationeffect and the coefficient of variation determined byhand-operated penetrometer tests for excavated lime-cementcolumns, were studied. The literature review, the description of the mixingprocess, and the results from the field tests provide a morebalanced picture of the mixing process and are expected to beuseful in connection to ground improvement projects and thedevelopment of mixing equipments. The concept of sufficient mixture quality, i.e. theinteraction between the mixing process and the mechanicalsystem, is discussed in the last section. By means ofgeostatistical methods, the analysis considers thevolume-variability relationship with reference to strengthproperties. According to the analysis, the design values forstrength properties depends on the mechanical system, the scaleof scrutiny, the spatial correlation structure, and the conceptof safety, i.e. the concept of sufficient mixture quality isproblem specific. Key words:Deep Mixing, Lime cement columns, Mixingmechanisms, Mixture quality, Field test, ANOVA, Variancereduction.
19

Underlying causes and stability of intraspecific variation in behaviour of microtine rodents

ŠÍCHOVÁ, Klára January 2017 (has links)
Two crucial issues related to personality in non-human animals have been identified: firstly, the underlying 'causes' of personality and,secondly, the stability of behavioural repertoires (essentially the defining feature of personality) have both been the subject of long-standing debate. This thesis is focused on investigating stable inter- and intra- individual differences in the behaviour of wildcaught bank voles, Myodes glareolus (that varied according to mtDNA type), and in common voles, Microtus arvalis. The first study, using wild voles, revealed empirical evidence about the effects of sex and mtDNA type on individual differences in basal metabolic rate and in behaviour in the open field which provides measures of approach and avoidance (here, generically termed 'proactivity') and which relate to several theoretical conceptualisations of animal personality. The second study demonstrated the presence of stable individual differences in reactions to exposure to open field test and radial maze in common voles, which were shaped by the social environment and in turn, related to cognitive efficiency. The same species was used in the third study documenting the distinct temporal patterns of behavioural plasticity that manifested over repeated exposures to the open field test. We suggest that this distinct temporal patterning in habituation, whilst it varied over time, was predictable in nature and therefore a reflection of a stable underlying personality. To conclude, this body of thesis work draws together a number of influencing factors, and considers their contribution to animal personality.
20

QTLs associados com emocionalidade em fêmeas pósparto de camundongos LG/J x SM/J

Monte, Bruno Gabriel Oliveira do 14 February 2012 (has links)
Made available in DSpace on 2016-06-02T20:21:28Z (GMT). No. of bitstreams: 1 4203.pdf: 1547039 bytes, checksum: fbfd6a9b5b93509ee40ca815bcf3a07b (MD5) Previous issue date: 2012-02-14 / Financiadora de Estudos e Projetos / In mammals, newborns need parental care, mostly maternal care, to succeed in development. Mother emotionality may affect development at initial stages or even emotionality of the offspring in adulthood. In the present study we investigate emotionality, in maternal period, by performing the open field test in mice females from SM/J, LG/J inbred lines and generations F1 and F2 from this intercross. F2 females were also tested in nonmaternal phase. We investigate if F2 females emotionality was associated with variation in weight gain and offspring viability. Finally, we perform QTLs analysis (Quantitative Trait Loci) aiming to study genetic architecture of emotionality at postpartum phase. Ethological analysis indicates that LG/J females seem to have higher level of anxiety when compared to SM/J females. F1 and F2 generations did not show significant differences in most of the phenotypes analyzed. In the contrast between maternal and non-maternal phases of F2 females, it seems females were less anxious in non-maternal phase. In the relationship between anxiety and weight gain among F2 females we observed that several ethological data show significant association with weight gain in some period of life of these females. However, the ethological variations do not seem to interfere in the offspring survival. QTL analysis revealed 11 individual QTLs associated to the phenotypes grooming, immobility, activity at center, and motor activity, that accounts between 5 and 9% of emotionality variation. Beside individual QTLs, we found a total of 88 epistatic QTLs involving the five evaluated phenotypes that together with the individual QTLs explain 24 to 53% of emotionality variation in postpartum females. The present study allowed the identification of putative candidate genes, as well as their relative size effects and patterns of gene action affecting mice emotionality. These results reveal that genetic architecture of emotionality of LG/J x SM/J dams is complex, since indicate the existence of many genes, including the interaction among them in a complex network of epistasis. Besides the genetic basis, is worth noted that environment also have a important impact in emotions through epigenetic mechanisms. / Em mamíferos, filhotes recém-nascidos necessitam de cuidados para que tenham sucesso em seu desenvolvimento. Esse sucesso está diretamente relacionado ao cuidado materno, cujas alterações na emocionalidade da mãe podem afetar o desenvolvimento dos filhotes nos estágios iniciais ou mesmo a própria emocionalidade dos filhotes na idade adulta. No presente estudo investigamos a emocionalidade no período materno, utilizando o teste de campo aberto, em fêmeas de camundongos SM/J, LG/J e gerações F1 e F2 deste intercruzamento, sendo a última também testada para fase não materna. Também averiguamos se a emocionalidade em fêmeas F2 estava associada com a variação do ganho em peso nestas fêmeas e com a viabilidade de sua progênie. Finalmente, utilizamos a análise de QTLs (Quantitative Trait Loci) com o intuito de estudar a arquitetura genética da emocionalidade na fase pós-parto. A análise etológica revela indícios de que fêmeas LG/J apresentam um maior nível de ansiedade quando comparadas com fêmeas SM/J. As gerações F1 e F2 não apresentaram diferenças significativas na maioria dos fenótipos analisados e no contraste entre fase materna e não materna para fêmeas F2, as últimas parecem ser menos ansiosa que as primeiras. Na relação entre ansiedade e ganho em peso entre as fêmeas F2, verificamos que vários dados etológicos estão significativamente associados com o ganho em peso em algum período da vida destas fêmeas. No entanto, as variações etológicas parecem não interferir na sobrevivência da progênie. A análise de QTL revelou 11 QTLs individuais associados aos fenótipos groming, imobilidade, atividade no centro e atividade motora, que respondem entre 5 a 9% da variação de emocionalidade. Além dos QTLs individuais, encontramos um total de 76 QTLs epistáticos envolvendo os cinco fenótipos avaliados, que juntamente com os QTLs individuais explicam de 24 a 53 % da variação de emocionalidade em fêmeas pós-parto. Este estudo permitiu a identificação de potenciais genes candidato, bem como o tamanho relativo dos efeitos do gene e os padrões de ação gênica afetando emocionalidade em camundongos. Esses resultados revelam que a arquitetura genética da emocionalidade de mães LG/J x SM/J é complexa, pois indica a existência de muitos genes, incluindo as interações entre eles em uma complexa rede de epistasia. Além da base genética, vale ressaltar que o ambiente também pode apresentar um grande impacto nas emoções por meio de mecanismos epigenéticos.

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