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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.
1

Persistence and heterogeneity in habitat selection studies

Usner, Dale Wesley 16 May 2000 (has links)
Recently the independent multinomial selections model (IMS) with the multinomial logit link has been suggested as an analysis tool for radio-telemetry habitat selection data. This model assumes independence between animals, independence between sightings within an animal, and identical multinomial habitat selection probabilities for all animals. We propose two generalizations to the IMS model. The first generalization is to allow a Markov chain dependence between consecutive sightings of the same animal. This generalization allows for both positive correlation (individuals persisting in the same habitat class in which they were previously sighted) and negative correlation (individual vacating the habitat class in which they were previously sighted). The second generalization is to allow for heterogeneity. Here, a hierarchical Dirichlet-multinomial distribution is used to allow for variability in selection probabilities between animals. This generalization accounts for over-dispersion of selection probabilities and allows for inference to the population of animals, assuming that the animals studied constitute a random sample from that population.. Both generalizations are one parameter extensions to the multinomial logit model and allow for testing the assumptions of identical multinomial selection probabilities and independence. These tests are performed using the score, Wald, and asymptotic likelihood ratio statistics. Estimates of model parameters are obtained using maximum likelihood techniques, and habitat characteristics are tested using drop-in-deviance statistics. Using example data, we show that persistence and heterogeneity exist in habitat selection data and illustrate the difference in analysis results between the IMS model and the persistence and heterogeneity models. Through simulation, we show that analyzing persistence data assuming independence between sightings within an animal gives liberal tests of significance for habitat characteristics when the data are generated with positive correlation and conservative tests of significance when the data are generated with negative correlation. Similarly, we show that analyzing heterogeneous data, assuming identical multinomial selection probabilities, gives liberal tests of significance for habitat characteristics. / Graduation date: 2001
2

Design and Evaluation of Three Alternative Keyboard Layouts for a Five-Key Text Entry Technique

Millet, Barbara 17 December 2009 (has links)
Despite the increase in popularity of handheld devices, text entry on such devices is becoming more difficult due to reduced form factors that limit display size, input modes, and interaction techniques. In an effort to circumvent these issues, research has found that five-key methods are effective for text entry on devices such as in-car navigation systems, television and gaming controllers, wrist watches, and other small devices. Five-key text entry methods use four directional keys to move a selector over an on-screen keyboard and an Enter key for selection. Although other researchers have described five-key character layouts using alphabetical order and predictive layouts based on digraph frequencies, there is considerable latitude in designing the rest of a comprehensive on-screen keyboard. Furthermore, it might be possible to capitalize on the relative strengths of the alphabetic and predictive layouts by combining them in a hybrid layout. Thus, this research examines the design of alternative keyboard layouts for five-key text entry techniques. Three keyboard layouts (Alphabetical, Predictive, and Hybrid) were selected to represent standard and less familiar arrangements. The analysis centered on a series of controlled experiments conducted on a research platform designed by the author. In this work, when the immediate usability of three alternative keyboard layouts for supporting five-key text entry was investigated, results indicated no statistically significant differences in performance across the tested keyboards. Furthermore, experimental results show that following immediate usability, but still at the onset of learning, there was no overall difference in performance among the three keyboard layouts across four text types. However, the Alphabetical keyboard surpassed both the Predictive and Hybrid keyboards in text entry speed in typing Web addresses. The nonstandard keyboards performed superior to the Alphabetical keyboards in typing Words/Spaces and Sentences, but performed no better in typing Address strings than the Alphabetical. Use of mixed effects modeling suggested that the longitudinal data was best fitted by a quadratic model. Text entry performance on all three layouts improved as a function of practice, demonstrating that participants could learn the unfamiliar layouts to complete text entry tasks. Overall, there was no indication that use of nonstandard layouts impedes performance. In fact, trend in time data suggests that the learning rates were greater for the nonstandard keyboards over the standard layout. Overall, participants preferred the Hybrid layout. In summary, this dissertation focused on creating and validating novel and effective five-key text entry techniques for constrained devices.
3

Fakability of a bio-data questionnaire and general intelligence

Schott, Doren Lee 01 January 1999 (has links)
No description available.
4

Population distribution, habitat selection, and life history of the slough crayfish (Procambarus fallax) in the ridge-slough landscape of the central Everglades

Unknown Date (has links)
Understanding where and why organisms are distributed in the environment are central themes in ecology. Animals live in environments in which they are subject to competing demands, such as the need to forage, to find mates, to reproduce, and to avoid predation. Optimal habitats for these various activities are usually distributed heterogeneously in the landscape and may vary both spatially and temporally, causing animals to adjust their locations in space and time to balance these conflicting demands. In this dissertation, I outline three studies of Procambarus fallax in the ridge-slough landscape of Water conservation Area 3A (WCS-3A). The first section outlines an observational sampling study of crayfish population distribution in a four hectare plot, where I statistically model the density distribution at two spatial scales. ... Secondly, I use radio telemetry to study individual adult crayfish movements at two study sites and evaluate habitat selection using Resource Selection Functions. In the third section, I test the habitat selection theory, ideal free distribution, by assessing performance measures (growth and mortality) of crayfish in the two major vegetation types in a late wet season (November 2007) and early wet season (August 2009). / by Craig van der Heiden. / Thesis (Ph.D.)--Florida Atlantic University, 2012. / Includes bibliographical references at the end of each chapter. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
5

Systém získávání a výběru pracovníků ve vybrané organizaci / Systém získávání a výběru pracovníků ve vybrané organizaci

ČABAJOVÁ, Karolína January 2018 (has links)
The subject of this diploma thesis is an analysis of the system of recruiting and selecting employees in a selected organization. In the theoretical part there is a defined of the personnel activities, the methods of recruitment and selection of employees. Also, the methods, which are used for the evaluation of the whole process. The practical part characterizes the selected company, its history and its organizational structure. This part also describes currently used methods of recruiting and selecting workers. The Conclusion contains proposals for changes that could lead to an improvement and acceleration of the whole process.
6

Métodos químicos para a estimativa do nitrogênio disponível do solo

Yagi, Renato [UNESP] 10 July 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-10Bitstream added on 2014-06-13T18:45:43Z : No. of bitstreams: 1 yagi_r_dr_jabo.pdf: 413490 bytes, checksum: a38c7eec6330f4c0a6acf335dd1ae765 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Foram avaliados 16 índices químicos de disponibilidade de N para a cultura do milho em 22 solos do Estado de São Paulo. Os índices químicos de disponibilidade de N foram matéria orgânica, N total, N inorgânico e N extraído com KMnO4/NaOH, H2O2/MnO, tampão fosfato-borato, K2Cr2O7/H2SO4, Na2Cr2O7.2H2O/H2SO4 e KCl a quente/MgO ou NaOH. Métodos biológicos de incubação de solo em condições aeróbias (35ºC por 30 semanas) e anaeróbias (40ºC por 7 dias), e experimento em casa de vegetação tendo o milho como planta-teste foram utilizados como padrões de referência para os índices químicos. Os métodos de extração do N disponível com KCl a quente/MgO e Na2Cr2O7.2H2O/H2SO4 apresentaram as melhores correlações com índices biológicos de mineralização ou disponibilidade de N. Na calibração destes métodos a partir de dois experimentos em vasos e em casa de vegetação, foram obtidos valores de nível crítico (NC) de N disponível que variaram de 33,0 a 35,0 mg dm-3 e de 430 a 525 mg dm-3, respectivamente. A partir destes valores de NC foram calculadas doses de N recomendadas (DR), com base em análise de N disponível em amostras de solo iniciais de três experimentos a campo e em experimento de incubação de solo em laboratório. A calibração dos métodos de análise para Nd do solo permitiu a obtenção do nível crítico de 35,0 mg dm-3 para o método do KCl a quente, como limite das classes de resposta e não resposta à adubação nitrogenada para a cultura do milho. Não foi possível calibrar o método de determinação de Nd com solução sulfocrômica. / Were evaluated 15 chemical indices for N availability for corn crop in 22 Sao Paulo State soils. The chemical indices of N availability were soil organic matter, total N, inorganic N and N extracted with KMnO4/NaOH, H2O2/MnO, phosphate-borate buffer, K2Cr2O7/H2SO4, Na2Cr2O7.2H2O/H2SO4, hot KCl/MgO or NaOH. Biological methods of soil incubation under aerobic conditions (35ºC for 30 weeks) and anaerobic (40ºC for 7 days), and experiment in a greenhouse taking the corn as test-plant were used as benchmarks for the chemical indices. The methods of extracting the N available with hot KCl/MgO and Na2Cr2O7.2H2O/H2SO4 showed the best correlation with N biological mineralization or availability. In the calibration of these methods from two experiments in pots and in greenhouse, were obtained critical level (CL) values of N available that ranged from 33.0 to 35.0 mg dm-3 and 430 to 525 mg dm-3, respectively. From these CL values were recommended N rates (NR), based on N available analysis in initial soil samples from three experiments in the field and in soil incubation in laboratory. In just one of the field experiments was possible to calculate NR of maximum economic efficiency, which were compared with NR. The calibration of the methods of analysis for N available soil allowed the achievement of CL of 35.0 mg dm-3 for the hot KCl method, as the limit of the classes of response and no response to nitrogen fertilization to corn cultivation. It was not possible to calibrate the method of determining of N available with sulfocromic solution.
7

Métodos químicos para a estimativa do nitrogênio disponível do solo/

Yagi, Renato. January 2008 (has links)
Resumo: Foram avaliados 16 índices químicos de disponibilidade de N para a cultura do milho em 22 solos do Estado de São Paulo. Os índices químicos de disponibilidade de N foram matéria orgânica, N total, N inorgânico e N extraído com KMnO4/NaOH, H2O2/MnO, tampão fosfato-borato, K2Cr2O7/H2SO4, Na2Cr2O7.2H2O/H2SO4 e KCl a quente/MgO ou NaOH. Métodos biológicos de incubação de solo em condições aeróbias (35ºC por 30 semanas) e anaeróbias (40ºC por 7 dias), e experimento em casa de vegetação tendo o milho como planta-teste foram utilizados como padrões de referência para os índices químicos. Os métodos de extração do N disponível com KCl a quente/MgO e Na2Cr2O7.2H2O/H2SO4 apresentaram as melhores correlações com índices biológicos de mineralização ou disponibilidade de N. Na calibração destes métodos a partir de dois experimentos em vasos e em casa de vegetação, foram obtidos valores de nível crítico (NC) de N disponível que variaram de 33,0 a 35,0 mg dm-3 e de 430 a 525 mg dm-3, respectivamente. A partir destes valores de NC foram calculadas doses de N recomendadas (DR), com base em análise de N disponível em amostras de solo iniciais de três experimentos a campo e em experimento de incubação de solo em laboratório. A calibração dos métodos de análise para Nd do solo permitiu a obtenção do nível crítico de 35,0 mg dm-3 para o método do KCl a quente, como limite das classes de resposta e não resposta à adubação nitrogenada para a cultura do milho. Não foi possível calibrar o método de determinação de Nd com solução sulfocrômica. / Abstract: Were evaluated 15 chemical indices for N availability for corn crop in 22 Sao Paulo State soils. The chemical indices of N availability were soil organic matter, total N, inorganic N and N extracted with KMnO4/NaOH, H2O2/MnO, phosphate-borate buffer, K2Cr2O7/H2SO4, Na2Cr2O7.2H2O/H2SO4, hot KCl/MgO or NaOH. Biological methods of soil incubation under aerobic conditions (35ºC for 30 weeks) and anaerobic (40ºC for 7 days), and experiment in a greenhouse taking the corn as test-plant were used as benchmarks for the chemical indices. The methods of extracting the N available with hot KCl/MgO and Na2Cr2O7.2H2O/H2SO4 showed the best correlation with N biological mineralization or availability. In the calibration of these methods from two experiments in pots and in greenhouse, were obtained critical level (CL) values of N available that ranged from 33.0 to 35.0 mg dm-3 and 430 to 525 mg dm-3, respectively. From these CL values were recommended N rates (NR), based on N available analysis in initial soil samples from three experiments in the field and in soil incubation in laboratory. In just one of the field experiments was possible to calculate NR of maximum economic efficiency, which were compared with NR. The calibration of the methods of analysis for N available soil allowed the achievement of CL of 35.0 mg dm-3 for the hot KCl method, as the limit of the classes of response and no response to nitrogen fertilization to corn cultivation. It was not possible to calibrate the method of determining of N available with sulfocromic solution. / Orientador: Manoel Evaristo Ferreira / Coorientadora: Mara Cristina Pessôa da Cruz / Banca: José Ricardo Mantovani / Banca: Tsuioshi Yamada / Banca: Heitor Cantarella / Banca: Wanderley José de Melo / Doutor
8

Co čteme dětem předškolního věku doma a v mateřské škole / Reading to Young Children at Home and in Kindergarten

Kubecová, Markéta January 2017 (has links)
The aim of this dissertation is to discover what kinds of books are the preschool children read by both their parents and their preschool teachers. The theoretical part defines the preliteracy of the readers and the preschool age, and describes the children's contact with books both at home and at kindergartens. Defines a book in the terms of a medium being in contrast to other communication means. The practical part is based on a mixed design of the research: the quantitative part uses the method of a questionnaire, and the qualitative part draws on the in-depth interviews, the respondents being the parents and preschool education teachers. At first, the questionnaires are compared. The decisive factors in parents and preschool educators selection of the books are characterized afterwards. The children are most frequently read storybooks and bedtime stories. Preschool teachers read out fables, parents do not. Furthermore, parents read out adventure literature. Thus, the parents and the school complement each other. Both at home and at school, children come into contact with prose as well as fiction. Adults prefer to read out older books, published mostly by Albatros Publishing, or they lend books in a library. At the same time, they carefully choose new titles of various publishing companies, for...
9

Modelling space-use and habitat preference from wildlife telemetry data

Aarts, Geert January 2007 (has links)
Management and conservation of populations of animals requires information on where they are, why they are there, and where else they could be. These objectives are typically approached by collecting data on the animals’ use of space, relating these to prevailing environmental conditions and employing these relations to predict usage at other geographical regions. Technical advances in wildlife telemetry have accomplished manifold increases in the amount and quality of available data, creating the need for a statistical framework that can use them to make population-level inferences for habitat preference and space-use. This has been slow-in-coming because wildlife telemetry data are, by definition, spatio-temporally autocorrelated, unbalanced, presence-only observations of behaviorally complex animals, responding to a multitude of cross-correlated environmental variables. I review the evolution of techniques for the analysis of space-use and habitat preference, from simple hypothesis tests to modern modeling techniques and outline the essential features of a framework that emerges naturally from these foundations. Within this framework, I discuss eight challenges, inherent in the spatial analysis of telemetry data and, for each, I propose solutions that can work in tandem. Specifically, I propose a logistic, mixed-effects approach that uses generalized additive transformations of the environmental covariates and is fitted to a response data-set comprising the telemetry and simulated observations, under a case-control design. I apply this framework to non-trivial case-studies using data from satellite-tagged grey seals (Halichoerus grypus) foraging off the east and west coast of Scotland, and northern gannets (Morus Bassanus) from Bass Rock. I find that sea bottom depth and sediment type explain little of the variation in gannet usage, but grey seals from different regions strongly prefer coarse sediment types, the ideal burrowing habitat of sandeels, their preferred prey. The results also suggest that prey aggregation within the water column might be as important as horizontal heterogeneity. More importantly, I conclude that, despite the complex behavior of the study species, flexible empirical models can capture the environmental relationships that shape population distributions.

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