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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.
171

DNA barcodes and meiofaunal identification

Mann, Jenna D. January 2010 (has links)
In recent years there has been a desire to definitively catalogue the life on our planet. In light of the increasing extinction rates that are driven by human activities, it is unlikely that this will be achieved using traditional methods. Whilst most organisms which have a body size of more than 1cm have been described, the vast majority of animal life is smaller than this, collectively known as meiofauna, and is yet to be catalogued. Meiofaunal organisms present a range of problems for traditional taxonomy. Firstly they are microscopic, meaning that morphological features are often difficult to resolve. Secondly these creatures often exhibit cryptic diversity meaning that different species often look the same. Thirdly, it is often the case that the organisms are poorly described in the literature making it very difficult to confirm identification, assuming that someone has already described it. It is possible, however, to obtain DNA sequences from these organisms. DNA barcoding, the use of short sequences of DNA to identify individuals, is now commonly used in a wide range of applications. It has been proposed that a single target gene should be sufficient to describe all organisms this way. Barcodes can be acquired from individuals or from bulk extractions from environmental samples. In the latter case, many of the sequences obtained are novel and unlikely to ever have a type specimen associated with them. When this is the case, assessing the diversity of a sample becomes a computational exercise. However, as yet, there is no agreed standard method adopted for analyzing the barcodes produced. Indeed most methods currently employed lack objectivity. This thesis investigates the efficiency of a range of gene targets and analysis methods for DNA barcoding, with an emphasis on meiofaunal organisms (nematodes, tardigrades and thrips). DNA barcodes were generated for up to three genes for each specimen. Sequences for each gene were analysed using two programs, MOTU_define.pl and DOTUR. These programs use different methods to assign sequences to operational taxonomic units (OTU), which were then compared. An objective method for analysing sequences such as MOTU_define.pl, which relies on only the information contained in the sequences, was found to be most suitable for designating taxa. It does not attempt to apply evolutionary models to the data, and then infer taxa from the derived data. In addition to barcoding, some samples were pre-processed using video capture and editing (VCE). This creates a virtual slide of a specimen so that a sequence can be linked to a morphological identification. VCE proved to be an efficient method to preserve morphological data from specimens.
172

Analysis of surface ships engineering readiness and training

Landreth, Brant T. 03 1900 (has links)
Approved for public release, distribution is unlimited / This thesis analyzes engineering readiness and training onboard United States Navy surface ships. On the west coast, the major contributor to training is the Afloat Training Group, Pacific (ATGPAC). The primary objective is to determine whether the readiness standards provide pertinent insight to the surface force Commander and generate alternatives that may assist in better characterization of force-wide engineering readiness. The Type Commander has many questions that should be answered. Some of these are addressed with Poisson and binomial models. The results include: first, age of a ship has no association with performance of drills and that the number of discrepancies is associated with the performance of drills; second, drill performance decreased from the first initial assessment (IA) to the second IA; third, on average, the number of material discrepancies decreases from the IA to the underway demonstration (UD) for ships observed over two cycles; fourth, good ships do well on four programs; finally, training is effective. A table characterizing ships as above average, average, or below average in drill effectiveness at the IA and UD is supplied. / Lieutenant, United States Navy
173

Enhancing the extended awareness capability of the ESG integrating Shotspotter and Cursor on Target technologies with unmanned aerial vehicles to enhance the mission capability of the ESG

Gibbons, Thomas J., Schaeffer, Kevin M. 06 1900 (has links)
This thesis discusses two emerging technologies and how their integration with UAVs can improve the situational awareness capability of the Expeditionary Strike Group. Shotspotter is an acoustic gunshot detection system and Cursor on Target is an XML based schema to enhance information exchanges. When integrated with UAVs, these two technologies will drastically improve an ESG's efficiency and lethality in combat.
174

Novel approaches to radiotherapy planning and scheduling in the NHS

Kapamara, T. January 2010 (has links)
The main subject matter of this thesis concerns radiotherapy patient scheduling subproblems formulated as four separate shop scheduling problem models (i.e. hybrid flowshop, flowshop, mixed shop and multiple identical parallel machine scheduling problems) based on the characteristics of the intricate real-life treatment processes observed at the Arden Cancer Centre in Coventry, UK. Insight into these processes was gained by developing and using a novel discrete-event simulation (DES) model of the four units of the radiotherapy department. By typifying the subproblems as well-known scheduling problem models, it was intended that methods amenable to them such as heuristics be used in the study. Four novel constructive heuristics based on priority dispatching rules and strategies adapted from some established algorithms have been developed and implemented using the C++ programming language. Further, these heuristics were incorporated into the DES model to create schedules of appointments for the patients generated daily. The effectiveness and efficiency of the constructive heuristics have been tested using the following performance criteria: minimising i) average waiting time to the start of treatment, and ii) average percentage of patients late for their treatment, and iii) the amount of overtime slots used for the patients received in a given period of time. The coordinated constructive heuristics and the DES model have also been tested using possible alternative pathways patients can follow in the treatment unit. The aim of these tests was to compare the efficiency of the radiotherapy department’s current pathway to other possible pathways. Further, strategies for using maximum allowed breaches of targeted due dates, reserved slots for critical treatments and overtime slots was also included in the heuristics. The results of several tests showed that the heuristics created schedules of appointments whose average waiting times for emergency, palliative and radical treatments improved by about 50%, 34% and 41%, respectively, compared to the historical data. However, their major slack was evidenced by the fact that about 13% of the patients needing palliative treatment were expected to be late for treatment compared to about 1% of those requiring radical treatment.
175

Modelování svozu gastroodpadu s využitím GIS / Modelling of gastro waste using GIS

Kyselová, Blanka January 2013 (has links)
Gastro wastes, as a sort of biodegradable waste, has been established in legislation just quite recently, and its sorting is just in the beginning. However as a sort of waste it has a great potential like a secondary material. This work deals with gastro waste modelling and optimization of their cartage routes with purpose to decrease negative implications with them connected. For the model composition, the operational research was used, namely the transportation task or the circular transportation problem, further optimization (that includes the linear optimization and the index method.) The program ArcGIS and its extension Network Analyst from ERSI were used for delineation of transportation routes. Microsoft Excel, Visual Basic and Python were used for computation of optimization tasks. Final graphic output was carried out in the ArcGIS ArcMap. The results of this work are optimized trucking cartage routes, calculated values of minimal distances, quantity of cartage cars, calculated overall costs and other calculations. The part of this tasks is also time conversion of the model. Also, the attention was paid for minimization of trucking routes. The increase of the capacity of specific gastro waste processors was used for the minimization. These processors were chosen in accordance with required...
176

Identifying relevant factors in implementing a chemistry curriculum in Botswana

Tawana, Lesego 08 July 2009 (has links)
A general concern in science education is that change in the curriculum has had little impact on the classroom practice. Following the introduction of a new curriculum called the Botswana Government Certificate in Secondary Education (BGCSE) curriculum in Botswana senior secondary schools, this study set out to investigate issues relating to implementation of the proposed curriculum, that is, mapping teaching effectiveness intended to improve students’ learning of chemistry compared with teaching during the old curriculum. This thesis reports the extent to which some chemistry teachers in Botswana senior secondary schools are implementing classroom methodologies that focus on learner-centred and hands-on activities. This investigation involved working with eleven chemistry teachers in four secondary schools in Botswana. The case study research methodology included observations and semi-structured interviews. The sub-constructs from Rogan and Grayson’s (2003) theory were used to guide data collection as well as analysis and interpretation of data. From the categories, it was possible to identify level of operation for the schools as well as the Zone of Feasible Implementation (ZFI) which spelt possible routes for interventions in individual schools. There were common areas observed about the teachers and the schools, in that they · All possessed the right qualifications to teach chemistry at senior school level. · All were relatively young in the teaching field · According to Rogan and Grayson’s (2003) scale, the teachers are operating at a very low level in the science practical and contextualisation dimensions. · Classroom dimensions were characterized by patches of rich interactions for most teachers. These were evidenced by some teaching interactions at level 3 on Rogan and Grayson’s operational levels. Some teachers’ lesson activities were more interactive in that there were presentations that encouraged the use of various communication skills. Learners presented organised information to support their positions, showing there had been a search for information before presentations. The other teachers limited involvement by learners, as their focus was on articulating the content. · Otherwise teachers were generally operating at lower levels in Rogan and Grayson’s (2003) scale. This is a clear indication that to some extent the teachers are not doing much in implementing the teaching ideas intended by the new curriculum. Mind and hands-on activities are still limited. Though teachers possess the right qualifications, there seems to be little desire to try new things. According to the operational levels on classroom interaction, practical work and contextualisation, it was found that teachers generally operated moderately on Rogan and Grayson’ scale. Though interviews results showed that teachers saw the need to have practical work as a way to actively engage learners, classroom observations showed that it was not a favoured method. Classroom observations revealed that the lecture method was still the favoured approach. Some learner-engaging activities in the form of group discussions, group experiments and demonstrations were practiced. Contextualizing of science was still generally low in all schools. The study also looked at the construct of capacity to support innovation. The three sub-constructs which were investigated in this study were physical resources, teacher factors and ecology and management systems. These factors had a great impact on how the sub-construct on profile of implementation panned out. The three factors were found to be higher on the Rogan and Grayson’s (2003) scale than the profile of implementation. This was found to be linked with a great deal of improvement of infrastructure by the Botswana government soon after the curriculum implementation e.g. science related facilities (laboratories, apparatus, chemicals) and teacher qualifications. Though this was the case, it was found out that classroom implementation was not as inflated as the resources on ground seemed to suggest. Several influential factors were found to be linked to the unfolding of a curriculum inside the classroom such as departmental contexts. The contexts were found to relate closely with the nature of communities that existed in science departments, which were linked to how teachers were distributed within departments.
177

A melhoria continua no processo de plantio da cana-de-açúcar / Continuous improvement of sugar cane planting process

Barros, Fernando Ferraz 07 November 2008 (has links)
A cultura da cana-de-açúcar no Brasil teve na safra 2007/2008 um aumento de 7,4% na área de plantio, sendo o estado e São Paulo responsável por 67% deste aumento. Estabelecer estas expansões ou reformas de canaviais com qualidade se torna imprescindível, pois a cana é uma gramínea perene com ciclo de quatro a cinco anos. Uma das alternativas para melhorar esta qualidade é a utilização de ferramentas como o controle estatístico do processo (CEP) que vem apresentando bons resultados nesta busca. Devido a importância da cultura da cana-de-açúcar, o aumento considerável no plantio da cultura e a exigência pela qualidade no setor, o objetivo deste trabalho foi identificar os fatores críticos e analisar o processo de melhoria continua no plantio da cana-de-açúcar. O trabalho foi desenvolvido na usina Pioneiros Bioenergia S.A e contou com o apoio da equipe técnica da usina. Na primeira etapa selecionaram-se as principais falhas do plantio, que posteriormente foram classificadas de acordo com a severidade, facilidade de ocorrência e de detecção. Em seguida definiram-se seus respectivos indicadores críticos, sendo eles o paralelismo, a profundidade de sulco, número de gemas viáveis por metro e altura de cobrição. Na segunda etapa se utilizaram histogramas, gráficos de controle e Pareto para avaliar a qualidade operacional no plantio, que se mostrou com grande instabilidade e variabilidade. Elaborou-se então, um conjunto de ações para diminuir esta instabilidade, denominado de plano de melhorias. Com a implantação deste plano deu-se inicio a etapa três, onde se avaliou novamente os indicadores considerados insatisfatórios. O paralelismo e a profundidade de sulco apresentaram um aumento dos dados dentro das especificações técnicas, porém, a altura de cobrição sofreu influência da época seca desfavorável para esta operação, proporcionando um aumento da terra na cobrição das mudas. Elaborou-se novamente, um segundo plano de melhorias e para isso utilizaram-se as informações dos gráficos de Pareto. Concluiu-se que a etapa dois apresentou-se com grande instabilidade e fora dos padrões estabelecidos. Com a implantação do plano de melhorias, etapa três, estes se mostraram com melhor estabilidade e com mais dados dentro das especificações. A utilização das ferramentas do CEP e do gráfico de Pareto se mostrou de grande valor na diminuição da instabilidade e melhoria dos processos, bem como na elaboração de um segundo plano de melhorias. / The sugar cane cultivation in Brazil, during the 2007/2008 period, showed a planting area increase of 7.4%. Sao Paulo state was responsible for 67% of this increase. It is vital to conduct those sugar cane plantation expansions and renovations with high quality, because sugar cane is a perennial grass, with a cycle of four to five years. A good alternative to improve plantation expansion and renovation process is the use of Statistical Process Control (SPC). The application of this tool has showed good results. Taking into consideration the great importance of sugar cane cultivation, the increase of sugar cane cultivation area and demand for higher quality, the purpose of this project is to identify critical factors and study the continuous improvement of sugar cane planting process. This project was developed in Pioneiros Bioenergia S.A. sugar mill and had the support of plant technical staff. In the first phase, the main planting failures were selected and classified by severity, occurrence probability and detection easiness. The critical parameters of the selected failures were also defined: furrow parallelism, furrow depth, number of good gemmas per meter and soil covering height. In the second phase histograms, control graphs and Paretto charts were used to evaluate planting operational quality, which showed high instability and variability. An action plan was then developed to reduce that instability, named Improvement Plan. The third phase started with improvement plan implementation, including reevaluation of critical parameters. There was an improvement of furrow parallelism and an increase of furrow depth values in accordance with specifications, but soil covering height was negatively influenced by dry season, which makes covering soil excess more likely to occur. A second Improvement Plan was developed, using Paretto chart information. It was concluded that the instability and values outside the established pattern observed in phase two were reduced by the implementation of the improvement plans carried out during phase three, which has shown better stability and more values in accordance with specifications. The application of SPC tools and Paretto charts was very useful in the process of obtaining planting process stability improvement, including the development of a second Improvement Plan.
178

Estudo da programação de atividades de desenvolvimento de poços de petróleo marítimos. / Study of the scheduling problem of offshore oil wells development activities.

Nishioka, Gilberto Koji 12 November 2013 (has links)
Este trabalho detalha o problema de programação de atividades de desenvolvimento de poços marítimos (PPADPM), cujo objetivo é definir o uso de sondas e navios, de forma a otimizar a produção de óleo dos poços marítimos. São apresentados cinco modelos baseados em programação linear-inteira mista (MILP) e um modelo gerado via programação por restrições (PR) para este problema. Concluiu-se que, dentre os modelos MILP, aquele baseado em variáveis que definem a ordem de execução das atividades apresenta os melhores resultados, tanto em termos de qualidade de soluções quanto em termos de tamanho do modelo. O aumento do tamanho da instância (em número de poços e/ou em número de recursos) traz como consequência um menor número de nós analisados dentro de um tempo limite de execução do modelo, ao mesmo tempo em que se observa que as estratégias de escolha de variáveis, de escolha de nós e de uso de solução inicial nos modelos MILP tornam-se ineficientes. Na comparação entre modelos MILP e o modelo baseado em PR, constatou-se que este último obteve as melhores soluções em mais de 90% dos casos analisados e, consistentemente, obteve mais soluções viáveis para cada instância. Entretanto, por não fornecer informações sobre a qualidade da solução, o modelo baseado em PR somente obtém a solução ótima ao analisar todo o espaço de busca do modelo; desta forma, este apenas chegou à solução ótima em instâncias com até quatro poços, enquanto alguns dos modelos MILP obtiveram a solução ótima para instâncias com até treze poços. / This work details the offshore wells activities on specialized resources scheduling problem, focusing on the optimization of the total oil production. A Constraint Programming (CP) model and five Mixed-Integer Linear Programming (MILP) models were studied. Among the linear models, those based on activities order variables are smaller, and led to the better solutions for almost all of the instances analyzed. As far as the size of the instances (number of wells and/or number of resources) increases, the number of branched nodes in a limited time decreases and, consequently, the influence of B&B nodes and variable selection strategies and of the initial guesses on the MILP model solution gets less efficient. Comparing best solutions for each instance, the CP model outperformed MILP models in 90% of the studied cases. In addition, the CP based model consistently found more solutions per instance than the MILP based models did. However, because the CP model does not give information on the quality of a solution (gap), it was only able to obtain optimal solutions for instances with up to four wells, while MILP based models found optimal solutions for instances up to thirteen wells.
179

Educators’ perceptions of operational competencies required in public schools

Chalmers, Janet 07 1900 (has links)
An educator is more than a person who just transmits knowledge. An educator plays many different roles in the lives of learners, colleagues and their immediate community. Educators have the opportunity to influence the community, develop learners holistically, create lifelong learners and reflective thinkers. For an educator to demonstrate such competence across a range of teaching roles and contexts, a vast range of operational competencies are required. The purpose of this study was to examine secondary school educators‟ perceptions of the operational competencies required to function in public schools. The literature study explored the roles of the educator and the operational competencies needed to function in a secondary school. A quantitative survey in the form of a questionnaire was used in the study to analyse the level of agreement that educators attached to certain operational competencies. The level of agreement indicated by the educators is likely to indicate the level of importance that they attach to the operational competency. A probability sampling technique in the form of simple random sampling was used in this study. Random samples were drawn from educators in secondary public schools in the Fezile Dabi and Sedibeng districts. A sample size of 280 educators was used. Of the 280 questionnaires that were administered, 49 were not returned and 20 were incomplete, resulting in 211 usable questionnaires. The results of the survey indicated that the competency factors that educators perceived to be of importance were: communication and behaviour management, interpersonal relationships, planning and assessment, leadership skills and perseverance and organisational commitment. The level of correlation of these identified factors with teaching satisfaction was also assessed- indicating that interpersonal relationships had the highest correlation with teaching satisfaction and factors like planning and assessment, organisational commitment and communication and behaviour management had a moderate influence on teaching satisfaction. v Leadership skills and perseverance do not have a great influence on teaching satisfaction. The value of the research is that it makes a useful contribution for planners in the Department of Education of South Africa by making them aware of the operational competencies required by educators in public schools. The results of the research could be used to develop the operational competencies that are not perceived by educators to be of importance and to enhance the teaching satisfaction of educators.
180

Avaliação das localidades ótimas para expansão da oferta de cana-de-açúcar no Brasil: uma aplicação de programação inteira mista / Investigation of the optimal locations to increase the sugarcane supply in Brazil: application of a mix and integer programing model

Branco, José Eduardo Holler 14 December 2012 (has links)
Essa tese tem como objetivo desenvolver um modelo matemático de programação mista para auxiliar na indicação das regiões ótimas para acréscimo da oferta de cana-de-açúcar no Brasil. Fazendo uso do ferramental desenvolvido almeja-se avaliar o comportamento espacial da produção de cana, dos fluxos de abastecimento e do consumo de açúcar e etanol mediante projeções futuras da demanda, e também mediante a incorporação dos novos projetos ferroviários, hidroviários e dutoviários na malha intermodal de transportes. Considerando as projeções do consumo doméstico e das exportações sucroalcooleiras para 2020/2021, o modelo matemático sugeriu as regiões ideais para aumentar a oferta de cana-de-açúcar, dentre as áreas com aptidão edafoclimática para o cultivo da cultura, visando a maximização da receita das indústrias do setor. As recomendações do modelo indicam acréscimo de 220 milhões de toneladas na produção dos canaviais do estado de São Paulo, 79 milhões em Mato Grosso do Sul, 70 milhões no Paraná, 65 milhões em Minas Gerais, 60 milhões na Bahia, 42 milhões em Goiás, 24 milhões no Tocantins, 15 milhões no Maranhão, 8 milhões no Mato Grosso e 7 milhões no estado do Piauí, nas condições do cenário com projeções de crescimento pessimista. Além disso, a alocação ótima dos fluxos de transporte de açúcar sugere uma participação de 45% do modal ferroviário, 52% do modal rodoviário e 3% de alternativas hidro-ferroviárias na produção total de serviços de transporte (TKU), considerando a demanda 2020/2021. No caso do etanol as proporções recomendadas indicam 61% para a modalidade rodoviária, 27% para a alternativa ferroviária e 12% para a combinação intermodal hidro-dutoviária. Os benefícios econômicos diretos proporcionados pela expansão da malha intermodal de transporte podem gerar economias com fretes próximas a R$ 444 milhões por safra, no escoamento da produção sucroalcooleira, baixando o frete unitário médio do setor de R$ 59,12 por tonelada para 54,12 por tonelada transportada. O método revelou-se uma ferramenta importante na análise da distribuição espacial da oferta de cana-de-açúcar, e os resultados geraram informações importantes para condução de políticas públicas e para organização do setor sucroenergético. / This thesis aims to construct a mathematical model of mix and integer programming for supporting the decisions about the best regions to increase the supply of sugar cane in Brazil. In addition is intended to use the model to provide inputs for analyzing the spatial sugar cane production and ethanol and sugar transport flows considering future supply and demand assumptions and different multimodal transportation network configuration. Supposing sugar and ethanol demand and exports projections to crop 2020/2021 the mathematical model recommended the optimum agricultural areas to increase the production of sugar cane in other to maximize the sector revenue. The model outputs recommended an increase of 220 million tons in sugarcane production at São Paulo state, 79 millions at Mato Grosso do Sul, 70 million at Paraná, 65 million at Minas Gerais, 60 millions at Bahia, 42 million at Goiás, 24 million at Tocantins, 15 million at Maranhão, 8 millions at Mato Grosso and 7 millions tons at Piauí. Regarding the sugar transportation flows the results proposed a share of 45% for rail mode, 52% for road and 3% for barge-rail alternatives in the total freight (Ton-Kilometer). In the case of ethanol the results indicated a share of 61% for road, 27% for rail, and 12% for barge-pipelines alternatives. The direct economic benefits provided by the expansion of multimodal transportation network implicates savings on freight near to R$ 444 million per crop, that involves a decrease from R$ 59.12 per ton to R$ 54,12 per ton in the unit freight cost. The mathematical model revealed be an important tool for spatial analysis of sugar cane supply in Brazil and the results provided important inputs for Federal Government policies and for planning the sugar and ethanol sector.

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