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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.
621

Kvapiųjų rozmarinų, Vaistinių ramunių ir Paprastųjų pankolių skystųjų ekstraktų technologijos ir kokybės vertinimas / Ethanolic liquid extracts of Rosmarinus officinalis, Matricaria recutita and Foeniculum vulgare technology and quality evaluation

Jašmontaitė, Lijana 18 June 2014 (has links)
Darbo tikslas - nustatyti, kaip technologiniai veiksniai (brinkinimo trukmė, ekstrahento koncentracija) lemia etanolinių skystųjų ekstraktų (iš rozmarinų lapų, pankolių vaisių, ramunių žiedų) kokybinę sudėtį. Darbo uždaviniai: 1. Remiantis mokslo literatūros duomenimis, parinkti žaliavos ir ekstrahento santykį, racionalų ekstrahentą bei ekstrahavimo metodą gaminamiems skystiesiems ekstraktams iš rozmarinų lapų, pankolių vaisių, ramunių žiedų. 2. Iširti brinkinimo trukmės ir ekstrahento koncentracijos įtaką pagamintų skystųjų ekstraktų kokybei, nustatant sauso likučio, bendrą fenolinių junginių kiekį ir antioksidacinį aktyvumą. 3. Iš gautų skystųjų ekstraktų pagaminti kompleksinį preparatą, tinkantį virškinamojo trakto (VT) veiklos sutrikimų šalinimui. 4. Įvertinti saugojimo laiko įtaką etanolinių skystųjų ekstraktų bei iš jų pagamintų mišinių kokybei. Tyrimo objektai ir metodai: Bendras fenolinių junginių kiekis rozmarinų lapų, ramunių žiedų ir pankolių vaisių etanoliniuose skystuosiuose ekstraktuose nustatytas spektrofotometriniu metodu pagal galo rūgštį. Antioksidacinis aktyvumas įvertintas spektrofotometriškai, naudojant DPPH• laisvojo radikalo sujungimo metodą. Gravimetriniu metodu nustatytas sausasis skystųjų ekstraktų likutis. Gauti rezultatai apdoroti naudojant Microsoft Office Excel 2010 ir Sigma Plot 12.0 programas. Tyrimo rezultatai ir išvados: Atlikti tyrimai rodo, kad 2 valandos – optimalus brinkinimo laikas, gaminant nagrinėjamų žaliavų skystuosius ekstraktus... [toliau žr. visą tekstą] / The aim of this research - to set how the technological factors (soaking duration, ethanol concentration) determine qualitative composition of ethanolic liquid extracts (from rosemary leaves, chamomile flowers, fennel fruit). The tasks of this research are: 1. According to the literature, to select proportion of the substance and extractive solvent, a rational extractive solvent and the method of production of liquid ethanolic extracts from rosemary leaves, fennel fruit and chamomile flowers. 2. To assess the impact of the soaking duration and ethanol concentration for quality of the liquid extracts by assessing dry residue level, amount of phenolic compouds and antioxidant activity. 3. To produce a complex product, from received ethanolic liquid extracts, suiting for digestive tract activity‘s disorders elimination. 4. To evaluate stability of ethanolic liquid extracts and from them produced compouds. The objects and methods of analysis: Rosemary leaves, chamomile flowers and fennel fruit ethanolic liquid extracts were analyzed by using spectrophotometric method for total amount of phenolic compounds expressed by gallic acid equivalents (GAE) and for evaluation of antioxidant activity by 2,2-diphenyl-2-picrylhydrazyl (DPPH) radical inactivation. Also gravimetric method was used for determination of dry residue levels. The results were obtained using Microsoft Office Excel 2010 and Sigma Plot 12.0 programs. Results and conclusions of analysis: According to all three methods... [to full text]
622

Modeling Phoneme Durations And Fundamental Frequency Contours In Turkish Speech

Ozturk, Ozlem 01 October 2005 (has links) (PDF)
The term prosody refers to characteristics of speech such as intonation, timing, loudness, and other acoustical properties imposed by physical, intentional and emotional state of the speaker. Phone durations and fundamental frequency contours are considered as two of the most prominent aspects of prosody. Modeling phone durations and fundamental frequency contours in Turkish speech are studied in this thesis. Various methods exist for building prosody models. State-of-the-art is dominated by corpus-based methods. This study introduces corpus-based approaches using classification and regression trees to discover the relationships between prosodic attributes and phone durations or fundamental frequency contours. In this context, a speech corpus, designed to have specific phonetic and prosodic content has been recorded and annotated. A set of prosodic attributes are compiled. The elements of the set are determined based on linguistic studies and literature surveys. The relevances of prosodic attributes are investigated by statistical measures such as mutual information and information gain. Fundamental frequency contour and phone duration modeling are handled as independent problems. Phone durations are predicted by using regression trees where the set of prosodic attributes is formed by forward selection. Quantization of phone durations is studied to improve prediction quality. A two-stage duration prediction process is proposed for handling specific ranges of phone duration values. Scaling and shifting of predicted durations are proposed to minimize mean squared error. Fundamental frequency contour modeling is studied under two different frameworks. One of them generates a codebook of syllable-fundamental-frequency-contours by vector quantization. The codewords are used to predict sentence fundamental frequency contours. Pitch accent prediction by two different clustering of codewords into accented and not-accented subsets is also considered in this framework. Based on the experience, the other approach is initiated. An algorithm has been developed to identify syllables having perceptual prominence or pitch accents. The slope of fundamental frequency contours are then predicted for the syllables identified as accented. Pitch contours of sentences are predicted using the duration information and estimated slope values. Performance of the phone duration and fundamental frequency contour models are evaluated quantitatively using statistical measures such as mean absolute error, root mean squared error, correlation and by kappa coefficients, and by correct classification rate in case of discrete symbol prediction.
623

Consequences of brain tumours from the perspective of the patients and of their next of kin

Edvardsson, Tanja January 2008 (has links)
A disease has consequences not only for the afflicted person but also for those who interact with him or her. A low-grade glioma is a brain tumour whose regarding its psychosocial implications for adult patients and their next of kin has received little attention in the literature. In the light of this the overall aim of the present thesis was to provide increased knowledge about how patients with low-grade glioma and their next of kin experience and deal with everyday life. The methods of the studies were mainly qualitative. Thirty-nine patients and 28 next of kin were interviewed and all except one next of kin completed a quality of life questionnaire. The onset of low-grade glioma was described from the patients’ perspective as a process, either rapid (up to a few months) or prolonged over several years. This phase of low-grade glioma encompassed repeated visits to physicians and care institutions. The onset of low-grade glioma was accompanied by stress, anxiety and uncertainty in the case of both the patients and those nearest. The symptoms and problems the patients experienced covered a broad range of consequences, physical, psychological and social. The patients presented a wide range of ways to cope with illness-related problems. The next of kin were often deeply involved in the patients’ situation and many of them experienced extremely stressful emotions mainly in the early period of the illness. They had experience of positive encounters in health care but more often they had had a sense both of powerlessness and of being invisible and neglected. Relations and roles changed in ways that mostly were experienced as negative. Enabling strength in everyday life had to do with alleviation of strain and having a positive outlook upon life. By means of the questionnaire Subjective estimation of Quality of Life (SQoL) the patients and those nearest estimated their quality of life as being comparatively high. Only one variable, among the patients the absence of work/meaningful occupation and among the next of kin the absence of own children, being estimated at below 60% of the maximum score.
624

Projektledning i praktiken : Observationer av arbete i korta projekt

Nilsson, Andreas January 2008 (has links)
Project management used to be described as rational and well structured - a notion that builds on a traditional view that project management is about planning, budgeting and controlling. Nevertheless, it has been questioned if this is a full description. Even though project management techniques were developed for large projects, those techniques and models are used today in small projects of short duration - projects that are quite dissimilar to the large ones. The present study takes a practice perspective to investigate what project managers do when they lead such short projects. Its observations and interviews are used to analyze what happens in the everyday life of project managers. Using classical managerial behaviour studies as a foundation, seen through a practice perspective lens, the study finds that the work of project managers in a software development project is fragmented – their time is filled with formal and informal meetings of different kinds and efforts to resist disturbances in the project. Three challenges were found in the project manager’s work. The first was to Understand: to create meaning. The plans were clearly defined at the start of the project but as the goals were later re-defined, it was scarcely possible to finalize them before delivery. Contrary to the traditional view that plans are inflexible, these plans were discussed, negotiated and interpreted throughout the project. This was the continuous work of creating both meaning in the plans and a common understanding of the project. The second challenge was to Order/coordinate: to manage resources. The project manager reacted to emerging issues rather than acting to prevent things from happening. These reactions led to creative ways of managing and finding solutions to problems. One important way of managing new or changed conditions was to reorganize resources to cover the needs of different teams. The meetings played a central role in this work as arenas for negotiating resources, which became especially evident in times of stress or high workload. The third challenge was to Make it in time: to manage time. Time is a central aspect of project management as projects are temporary organizations; they have a beginning and an end. Previous research has found a point in time, in the middle of a project, when the team starts to feel pressured and stressed about meeting their deadlines. For project managers there is always a struggle to manage time, as dates for delivery are one of the things in a project that are not negotiable. In short-duration projects where projects follow each other seriatim, there is an almost constant feeling of urgency; stress and pressure. The project manager used experiential data to determine and plan the amount of time that would be needed to manage changes in the project, intending that the slack created would enable the project to deliver on time. Although changes and deviations were expected, the project manager rarely knew beforehand what they were or when they would come. The three challenges, previously described as separated from each other, were observed to be all managed simultaneously. The site, the practitioner and the practices influence daily work practice.
625

Modeling and control of fuel cell based distributed generation systems

Jung, Jin Woo, January 2005 (has links)
Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xvi, 209 p.; also includes graphics. Includes bibliographical references (p. 202-209). Available online via OhioLINK's ETD Center
626

A comparative analysis of proportional-integral compensated shunt active power filters

Gray, Matthew Alan. January 2004 (has links)
Thesis (M.S.) -- Mississippi State University. Department of Electrical and Computer Engineering. / Title from title screen. Includes bibliographical references.
627

Utilização de dois intervalos de descanso entre pastoreios em pastagem natural com novilhas de corte na estação quente / Use of two rest intervals between grazing in natural grassland heifers with cutting in hot season

Barbieri, Cezar Wancura 21 February 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to evaluate the performance and ingestive behavior of beef heifers grazing natural grassland managed under rotational grazing according to two rest periods in spring and summer. The treatments were two intervals between grazing 375 and 750 DD (degree days), based on thermal cumulative average for leaf expansion of native grasses belonging to two functional groups. The experimental design was randomized complete block design with two treatments and three replications. The experiment was conducted from November 2011 to April 2012. The test animals were Angus beef heifers, with an initial mean age of 12 months and initial weight 185.2 ± 17.4 kg. The ingestive behavior variables evaluated were grazing time, rumination and rest, and daily number and duration of meals, bite rate, number of stations visited per minute, number of steps between feeding stations, length of stay at the station. All variables of ingestive behavior were similar between treatments. However, grazing time and biting rate ranged between assessments. The different intervals between grazing on natural pasture did not influence the patterns of ingestive behavior of heifers. The variables of pasture mass of green leaf and stalk weight in different time periods evaluated the influence of grazing, ruminating and bite rate. Forage mass was higher in the 750 DD treatment, however, the mass of leaf blades were similar among treatments. The highest average daily gains and gains per area were observed in 375 DD treatment. In one evaluation period there was weight loss in animals of both treatments, that was attributed to a drought occurred and the lowest mass of leaf blades of the period. The average stocking density was similar between treatments. The treatment of lower defoliation interval presented greater individual gain. / O objetivo deste estudo foi avaliar o desempenho produtivo e o comportamento ingestivo de novilhas de corte em pastagem natural manejada sob pastoreio rotativo em função de dois intervalos de descanso na primavera-verão. Os tratamentos avaliados foram dois intervalos entre pastoreios 375 e 750 GD (graus-dia), baseados na soma térmica média acumulada para a expansão foliar de gramíneas nativas pertencentes a dois grupos funcionais. O delineamento utilizado foi em blocos completamente casualizados com dois tratamentos e três repetições de área. O experimento foi conduzido de novembro de 2011 a abril de 2012. Os animais testes foram novilhas de corte, da raça Angus, com idade média inicial de 12 meses e peso inicial 185,2 ± 17,4 kg. As variáveis do comportamento ingestivo avaliadas foram o tempo de pastejo, ruminação e ócio, além de número diário e duração das refeições, taxa de bocados, número de estações visitadas por minuto, número de passos entre estações alimentares, tempo de permanência na estação. Todas as variáveis do comportamento ingestivo foram semelhantes entre os tratamentos avaliados. No entanto, o tempo de pastejo e a taxa de bocados variaram entre as avaliações. Os diferentes intervalos entre pastoreios em pastagem natural não influenciou os padrões de comportamento ingestivo das novilhas. As variáveis do pasto MLFV e massa de colmos nos diferentes períodos avaliados influenciaram nos tempos de pastejo, ruminação e taxa de bocados. A massa de forragem foi superior no tratamento 750 GD, no entanto, a massa de lâminas foliares foi semelhante entre os tratamentos. Os maiores ganhos médios diários e ganhos por área foram observados no tratamento 375 GD. Em um dos períodos de avaliação houve perda de peso nos animais de ambos os tratamentos, que foi atribuído ao déficit hídrico ocorrido e a menor massa de lâminas foliares do período. As cargas médias foram semelhantes entre os tratamentos. O tratamento de menor intervalo entre desfolhas proporcionou aos animais maior ganho individual.
628

Análise das variáveis tempo e distância no método “pontos de contagem” no estudo da assembleia de aves na estação ecológica de Caetetus (EECa), São Paulo

Gerotti, Raphael Whitacker January 2017 (has links)
Orientador: Reginaldo José Donatelli / Resumo: Pontos de contagem é um método atrativo para utilização em programas de monitoramento de aves por ser simples e permitir que vários locais sejam amostrados. Contudo, nos estudos realizados em regiões tropicais utilizando-se deste método, os autores utilizam a variável "tempo" de forma diferente para registrar a abundância das aves nos fragmentos florestais. Portanto, os dados obtidos por estes diferentes estudos não podem ser comparados entre si, pois o tempo gasto nos pontos e o tempo total das contagens diferem significativamente, assim como as distâncias percorridas. Desta forma, o objetivo do presente trabalho foi o de comparar quatro durações de tempos distintas (5, 10, 15 e 20 minutos) para identificar qual destas registra maior riqueza e abundância de aves em fragmentos de florestas tropicais. As amostragens foram realizadas durante 12 meses em um fragmento de floresta estacional semidecidual de 2.180 ha no interior de São Paulo. Um total de 120 minutos de amostragem foi realizado a cada mês para cada tempo distinto, o que exigiu um número diferente de pontos amostrais e uma diferente distância total percorrida na floresta. Com relação à riqueza e abundância, os testes estatísticos evidenciaram que o tempo de cinco minutos apresentou resultados que diferem significativamente dos outros tempos (10’, 15’ e 20’). Além disso, houve uma correlação positiva entre as diferentes distâncias percorridas e a abundância registrada, ou seja, quanto maior a distância percorrida, mai... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Point counts are attractive for use in avian monitoring programs because they are straightforward and allow numerous geographic sites to be sampled. However, in studies conducted with the point count method in tropical regions, authors use the variable "time" differently to record the abundance of birds in forest remnants. Therefore, the data obtained by different studies cannot be compared since the time spent at the points and the total counting time differ significantly, as do the distances traveled. The objective of the present study was to compare four distinct point count times (5, 10, 15 and 20 minutes) to identify which registers relatively greater bird richness and abundance in tropical forest fragments. Samplings were carried out for 12 months in a 2,180 ha fragment of semideciduous forest in the interior of the state of São Paulo. A total of 120 minutes of sampling was carried out each month for each counting time, which required a different number of counting points and a different total distance traveled in the forest. With respect to richness and abundance, the statistical tests showed that five minutes of counting yielded results that were significantly different from those of the other point count times. Additionally, there was a positive correlation between the different distances traveled and the recorded abundance, i.e., the greater the distance traveled, the greater the richness and abundance. One aspect of community ecology that must be considered is that... (Complete abstract click electronic access below) / Mestre
629

Experiences of Racism and Breastfeeding Initiation and Duration Among First-Time Mothers of the Black Women’s Health Study: A Dissertation

Griswold, Michele K. 27 April 2017 (has links)
BACKGROUND: Breastfeeding and lactation are cited as sensitive periods in the life course that contribute to the accumulation of risks or opportunities ultimately shaping vulnerability or resilience later in life. As such, breastfeeding and lactation are critical components of health equity. Despite this, Black women in the U.S. initiate and continue to breastfeed at lower rates than White women and other groups. Underlying reasons for racial inequities in breastfeeding rates are poorly understood. Exposure to racism, one manifestation of historical oppression in the U.S. has been cited as a determinant of poor health outcomes for decades but has not been extensively described in the context of breastfeeding. AIMS: To investigate the association between experiences of racism and 1.) breastfeeding initiation 2.) breastfeeding duration 3.) and the association between selected life-course factors and breastfeeding initiation and duration among participants of the Black Women’s Health Study. METHODS: This study was a prospective secondary analysis of the Black Women’s Health Study. The sample included all participants who enrolled in 1995, responded to the racism assessment in 1997 and reported the birth of a first child following the racism assessment resulting in an N=2, 995 for the initiation outcome and N= 2,392 for the duration outcome. In addition to the racism assessment, we also included life-course factors (nativity, neighborhood segregation and social mobility). For each aim, we calculated odds ratios and 95% confidence intervals using binomial and multinomial logistic regression using two models. The first adjusted for age, the second adjusted for age, BMI, education, marital status, geographic region, neighborhood SES and occupation. RESULTS: Associations between daily and institutional summary racism variables and breastfeeding initiation and duration were small and not statistically significant. Experiences of racism in the job setting was associated with lower odds of breastfeeding duration at 3-5 months compared with 3 months 95% CI [0.60, 0.98]. Experiences of racism with the police was associated with higher odds of breastfeeding initiation and duration at 3-5 months [1.01, 1.77] and at 6 months [1.10, 1.82] compared with women who did not report this experience. The participant’s nativity and the nativity of her parents were life-course factors that predicted lower odds of breastfeeding initiation and duration. Neighborhood segregation did not reach statistical significance after adjusting for covariates but results trended toward lower odds of breastfeeding initiation and duration for women who reported living in a predominately Black neighborhood (compared with White) up to age 18 and for women who reported living in a predominately Black neighborhood in 1999. CONCLUSION: Experiences of institutional racism in the job setting was associated with lower odds of breastfeeding duration. In addition to explicit experiences of racism, this study provides preliminary evidence surrounding life-course factors and breastfeeding. Individual level interventions may mitigate harmful effects of racism but structural level interventions are critical to close the gap of racial inequity in breastfeeding rates in the U.S.
630

Résolution de problèmes multicritères (durée/sécurité) pour la conception de plans d'évacuation de personnes / Solving multicriteria problems (duration/safety) in order to design large scale evacuation evacuation planning

Ndiaye, Ismaïla Abderhamane 03 March 2016 (has links)
Les travaux présentés dans cette thèse visent à proposer des méthodes de routage d’une population de masse à travers un réseau perturbé dont les données varient dans le temps pour l’aide à la conception de plan d’évacuation. Ce problème s’illustre parfaitement en cas de catastrophe d’origine humaine ou naturelle où les populations (potentiellement) impactées par ces sinistres doivent quitter leur lieux de vie pour une période pouvant aller d’un à plusieurs jours. Dans la littérature, ces routages de masse sont souvent modélisés comme des problèmes de flots dynamiques dont l’objectif est de minimiser la durée globale du transfert des individus depuis un certain nombre de points de départs dangereux vers des points d’arrivé sûrs. Toutefois, peu de travaux prennent en compte la notion de sécurité durant ce routage et encore moins le déploiement d’agents (policiers, sapeur-pompiers, ambulanciers,...) pouvant sécuriser et/ou faciliter le déplacement des personnes. / The work presented in this thesis aims to propose methods for routing a mass population through a disturbed network whose data vary over time. This problem can be illustrated by disasters due to humans or natural events where people (potentially) affected have to leave their living places for a period of one to several days. In the literature, mass routing are often modeled as dynamic flow problems whose objective is to minimize the overall duration of the evacuation process from a set of gathering points towards another set of shelter locations. However few papers take into account the concept of safety during this routing nor deploying task forces that can secure or facilitate this process. In this context, the safety security can be seen as a danger affecting the quality of life of people we organize the trip. In this context, the safety can be seen as a danger that influence the health of the people we are trying to evacuate. Indeed, this hazardous event can be related to a radioactive cloud, a fire, a tsunami, an earthquake or a flooding which make some of paths becoming dangerous or less usable by evacuees.

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