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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.
121

L'influence de la variabilité climatique sur l’enracinement superficiel et profond d'arbres adultes en plantation : les cas de l’hévéa (hevea brasiliensis) et du teck (tectona grandis) sous contraintes hydriques en Asie du sud est / Effects of climate variability on shallow and deep root growth of mature rubber (Hevea brasiliensis) and teak (Tectona grandis) trees in south-east Asian plantations

Maeght, Jean-Luc 16 September 2014 (has links)
Le système racinaire, lien essentiel entre la plante et le sol quoi qu'essentiellement invisible, reste encore aujourd'hui peu étudié dans son ensemble. Les plantes étant ancrées au sol via leur système racinaire, leurs facultés d'adaptation et de survie sont donc très dépendantes de leurs capacités à savoir tirer profit de l'espace qui les entoure, notamment par l'intermédiaire de leur système racinaire. Certains arbres font néanmoins partie des plus grands et plus anciens êtres vivants de la planète, preuve s'il en est de leur capacité d'adaptation au milieu dans lequel ils poussent et aux changements environnementaux pouvant survenir dans le temps. Dans le cas des plantations, les contraintes anthropiques imposées se heurtent parfois aux limites de cette formidable capacité d'adaptation. Les travaux développés dans la première partie de cette thèse font l'objet de deux articles publiés et se concentrent sur une revue bibliographique des connaissances sur l'enracinement profond. Le rôle vital du système racinaire pour la plante est ainsi mis en avant ainsi que ses fonctions dans le continuum sol-plante-atmosphère. Son rôle essentiel, souvent sous-estimé dans le stockage du carbone, est également abordé. Les différentes techniques permettant d'accéder aux systèmes racinaires in situ sont passées en revue et nous présentons la technique du puits d'accès que nous avons utilisé pour observer les racines jusqu'à 5 mètres de profondeur. Nous avons également développé nos propres outils de prise de vue par l'intermédiaire de scanner à plat ainsi qu'un outil d'analyse d'images ( IJ_Rizo) aujourd'hui disponible en ligne.Dans la deuxième partie du mémoire, nous nous consacrons à l'étude du système racinaire de l'hévéa adulte (Hevea brasiliensis) dans le nord-est de la Thaïlande. Premier producteur mondial de caoutchouc naturel, la Thaïlande a fortement développé ses plantations d'hévéas allant jusqu'à étendre son exploitation au-delà de sa zone climatique naturelle, dans des zones à fortes contraintes hydriques. Dans ce contexte, nous avons étudié la saisonnalité et la dynamique des racines fines pendant trois ans ainsi que leur contribution au cycle du carbone. Nous avons pu mettre en évidence la continuité de la dynamique racinaire indépendamment des périodes de défoliation mais en lien avec la saisonnalité de la pluviométrie. Nous avons également pu caractériser la faible différenciation de la dynamique racinaire de 0 à 4,5 mètres de profondeur dans un tel contexte. La troisième partie de la thèse concerne l'étude du teck (tectona grandis), espèce endémique d'Asie du Sud-Est, et notamment du Laos dans la région de Luang Prabang. Le développement de sa culture sous forme de plantations mono-spécifiques se poursuit depuis les années 80. En appliquant la technique d'exclusion de pluie pendant 2 ans sur des arbres d'une plantation d'une vingtaine d'années, nous avons observé l'influence du régime de précipitations sur l'enracinement. Un arrêt pratiquement total de croissance des racines en surface et en profondeur a ainsi été mis en évidence. Nous concluons, dans le cas d'espèces à une forte dépendance à la ressource en eau de surface, à un impact direct sur l'état physiologique et une stagnation de la croissance des troncs. Certains individus ont démontré une capacité d'adaptation en modifiant leur cycle de foliation / défoliation accompagné d'une reprise de la croissance des troncs lors de la deuxième année du régime de sécheresse imposé. Nous avons également démontré l'importance de l'enracinement fin pour le stockage du carbone qui, dans ce contexte, représente plus de 45 % du carbone total, soit environ le double des données publiées dans la littérature.Les données obtenues pour les espèces étudiées dans ce mémoire pourront être utilisées pour la modélisation de scenarios simulant le changement climatique et le changement d'usage des terres. / The root system is essential but essentially invisible. Plants are anchored to the soil through their root system; their adaptation and survival abilities are highly dependent on their ability to learn to take advantage of the space that surrounds them. Certain trees are nevertheless some of the largest and oldest living species on the planet- evidence of their ability to adapt to changes in their environment. Within managed anthropogenic constraints, particular species are vulnerable. It is clear that a wide range of parameters are likely to influence the root system and its operation, which offers many entry points to improve our understanding of a root's capacity for expansion, its dynamics, its role within the plant itself and within the soil plant atmosphere continuum. Available data on the extent and dynamics of plant roots includes several thousand references. However, the vast majority of these observations were made within the first meter of the soil profile. Data acquisition for the fine and/or deep roots is currently limited by constraints of time and financial resources. To overcome this lack of information, while trying to assess root dynamics under different environmental conditions, many models have been developed. However, it is still difficult to describe the complexity of root development in the community and to integrate its "plasticity".To understand such a complex environment, we must work toward establishing a definition of objectives and the tools necessary to develop and implement them. The work developed in the first part of this thesis is the subject of two articles and focuses on a literature review about deep roots. The vital role of the root system for the plant is well highlighted, as is its impact as a link within the atmosphere. We discuss the role of deep roots in carbon storage, which is critical and often underestimated. The different techniques for accessing the root systems in situ are also considered, and we present our access technique for observing the roots down to depths of five meters. We have also developed tools for shooting through a flatbed scanner and image analysis ( IJ_Rizo ) now available online.In the second part of the thesis, we focus on the study of root systems of adult rubber trees (Hevea brasiliensis L. RRIM 600) in the northeast of Thailand. Thailand has greatly expanded its acreage to extend its operations beyond its natural climate zone, into areas of high water stress. In this context, we studied the seasonality and dynamics of fine roots for three years and their contribution to the carbon cycle. We were able to highlight the continuity of root dynamics during independent periods of defoliation, yet link these to the seasonality of rainfall. We were also able to characterize the low differentiation of root dynamics at 0 to 4.5 m of depth in this context.The third part of the thesis concerns the study of teak particular to the region of Luang Prabang, Laos. By applying the rain exclusion technique for 2 years on a plantation of twenty-year-old trees, we observed the influence of precipitation patterns. During the period of water stress, an almost total cessation of root growth, at the surface and significant depths, has been highlighted. We conclude that in the case of species with a high dependence on water resources there is a direct impact on the physiological state and stagnated trunk growth. Some individuals have demonstrated an ability to adapt by changing their foliation/defoliation cycle, accompanied by a resumption of trunk growth during the second year of imposed drought. We also demonstrated the importance of rooting as a means of carbon storage, which in this context represents more than 45% of total carbon- roughly double the amount published in other literature .The data obtained for the species studied in this paper can be used for modelling scenarios simulating climate change and changing land use.
122

Barreiras econômicas na exploração em terra de campos maduros e marginais: o caso da bacia Potiguar / Economic barriers in onshore mature oil fields: the case of Potiguar basin

Pedro Barbosa Mantovani Batista 05 October 2016 (has links)
O surgimento da Lei do Petróleo, Lei 9.478/97, abriu uma nova frente de investimentos para o capital privado. O setor de exploração e produção de petróleo, antes sob monopólio estatal, passou a ser de interesse de diversas empresas privadas. Com a supervisão da ANP, surgiram as rodadas de licitações para concessão do direito de exploração e produção de petróleo dos campos ofertados. Os campos maduros e marginais foram então uma oportunidade de fomento aos negócios de petróleo devido à necessidade de uma operação mais eficiente, porém exigindo menores investimentos e necessidade técnica específica. Esta dissertação tem por objetivo expor o panorama econômico do setor de exploração e produção de petróleo para pequenas e médias empresas que atuam na região da Bacia Potiguar, Rio Grande do Norte, a partir de pesquisas e levantamentos de dados sobre: os conceitos teóricos de campos marginais e maduros e de pequenas e médias empresas; o histórico brasileiro de produção independente de petróleo; a geografia física e humana da Bacia Potiguar; e as barreiras econômicas encontradas por pequenas e médias empresas que atuam no setor de exploração e produção de petróleo. Depois de apresentadas e justificadas todas as hipóteses, são realizadas simulações de diferentes cenários para análise da viabilidade de um empreendimento de reativação de um campo marginal de petróleo. Utilizando a metodologia de fluxo de caixa descontado, foi possível avaliar o Valor Presente Líquido, Taxa Interna de Retorno e Payback do empreendimento. A partir da análise do fluxo de caixa e da sensibilidade de algumas premissas, avaliou-se o comportamento do Valor Presente Líquido do empreendimento em função das mudanças do preço de venda do barril de petróleo, do volume de produção do campo e de outros parâmetros escolhidos. Por fim, foi feita uma comparação entre trabalhos cujos autores propuseram temas semelhantes, para efeito de comparação e comprovação da sensibilidade e viabilidade dos campos. / The emergence of the Petroleum Law, Law 9.478/97, opened a new investment front for private capital. The upstream sector, previously under state monopoly, became a focus of interest from several private companies. With the supervision of the ANP, came rounds of bidding to grant exploration and production rights to the available oil fields. Mature and marginal fields were then a development opportunity in the oil business due to the need for a leaner operation, while requiring less investment and specific technical necessity. This thesis aims to expose the economic outlook of the onshore upstream sector for small and medium-sized companies operating in the Potiguar Basin region, Rio Grande do Norte, based on research and data surveys about: the theoretical concepts of marginal and mature fields and small and medium companies; the history of Brazilian independent oil production; the physical and human geography of the Potiguar Basin as well as the economic barriers faced by small and medium-sized companies operating in the oil exploration and production sector. After the presentation and justification of all hypotheses, simulations are carried out with different scenarios for analyzing the feasibility of the reactivation of a marginal oil field. Using the discounted cash flow method, it was possible to evaluate the Net Present Value, Internal Rate of Return and Payback of the project. From the analysis of cash flow and the sensitivity of some assumptions, we evaluated the behavior of the Net Present Value due to the sale price changes of the oil barrel, the volume of oil production in the field and other chosen parameters. Finally, a comparison between other papers whose authors have proposed similar themes was made, for comparison and verification of the sensitivity and viability of the fields.
123

Fenóis totais no cafeeiro em razão das fases de frutificação e do clima. / Total phenols in the coffee tree due to the fructification phases and the climate.

Paula Rodrigues Salgado 14 January 2005 (has links)
Os vegetais apresentam defesa natural contra os fatores externos, bióticos e abióticos, por meio da síntese de compostos fenólicos no metabolismo secundário, as quais variam com as fases fenológicas e com o clima. O aumento dos compostos fenólicos nas plantas está, diretamente, relacionado com a resistência à infecção por patógenos e à infestação de pragas. Entretanto, pouco se sabe sobre a variação dos teores dessa substância durante os estádios fenológicos do cafeeiro, em particular, nas fases de frutificação, e em razão das condições climáticas. Tais conhecimentos são fundamentais para a previsão dos riscos de ataques aos vegetais, uma vez que a defesa natural da planta deve mudar ao longo do ciclo. O experimento foi realizado em uma cultura de Coffea arabica L., cultivar Obatã IAC 1669-20, instalada no campo experimental do Departamento de Produção Vegetal, da Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, Piracicaba/SP. Para a realização do experimento foi adotado o delineamento experimental inteiramente casualizado, utilizando quatro tratamentos (plantas com e sem frutos - folhas dreno e plantas com e sem frutos - folhas fonte) e cinco repetições constituídas por plantas individuais. Após a análise de variância dos resultados foi aplicado o teste t de Student ao nível de 5 % de significância para a comparação das médias entre os tratamentos. Os teores de fenóis totais (µg g-1) foram extraídos das folhas maduras (fonte) e novas (dreno) e analisados em relação à produção de café, fenologia e clima. As variáveis climáticas adotadas foram temperatura atmosférica (média, mínima e máxima; oC), radiação global (MJ m-2 dia-1) e insolação diária (h dia-1). Durante a condução do experimento foram realizadas avaliações de altura da planta (cm), diâmetro do caule (mm) e comprimento de ramos plagiotrópicos (cm) para determinar as respectivas taxas de crescimento vegetativo das plantas. As quantidades de fenóis totais determinadas nas plantas com produção (17.40 µg g-1 e 13.89 µg g-1 folhas dreno e fonte, respectivamente) e sem produção de café (18.65 µg g-1 e 12.76 µg g-1 folhas dreno e fonte, nessa ordem) não variaram. No entanto, a concentração de fenóis totais nas folhas novas (dreno) das plantas com e sem produção de café foi maior que a quantidade determinada nas folhas maduras (fonte), da ordem de 25 % e 46 %, respectivamente. A síntese de fenóis nas fases de expansão (16.35 µg g-1) e granação dos frutos (14.68 µg g-1) foi 31 % inferior em relação às quantidades determinadas na fase de maior produção dessas substâncias – fruto em maturação (21.24 µg g-1). A metabolização de fenóis totais depende, indiretamente, da temperatura (oC) e da radiação global (MJ m-2 dia-1), apresentando tendência inversa em relação a estas variáveis climáticas. A orientação do manejo fitossanitário deve levar em consideração as épocas em que há comprometimento da defesa natural da planta, em relação à produção de substâncias protetivas – os fenóis. / The vegetables show a natural defense against external factors, biotic and abiotic, by the synthesis of the phenolic compounds in the secondary metabolism, which varies with the maturity state and with the climate. The increase of phenolic compounds in the plants is directly related to the resistance to the infection thought pathogens and insect infestation. However, little is known about the variation in the content of this substance during the maturity state of the coffee tree, particularly in the fructification phases due to the climatic variations. Such knowledge is the base for the risks analyses of attacks to vegetables, since the natural defense of the plant shall change during the cycle. The experiment was carried out in a Coffea arabica L. crop, to cultivar Obatã IAC 1669-20, installed in the experimental field of the department of vegetal production of the Escola Superior de Agricultura "Luiz de Queiroz", University of São Paulo, Piracicaba/SP. For the accomplishment of the experiment it was adopted a totally randomized experimental design, using four treatments (plants with and without fruits – drain leaves and plants with and without fruits – source leaves) and five repetitions consisting of individual plants. After analysing the variance of the results it was applied Student t test at the level of 5 % of significance to compare the averages between the treatments. The total phenol grade (µg g-1) have been extracted from the mature (source) and new (drain) leaves and have been analyzed in relation to the coffee yield, phenology and climate. The climatic conditions adopted were atmospheric temperature (average, minimum and maximum; oC), global radiation (MJ m-2 day-1) and daily insolation (h day-1). During the conduction of the experiment it was analyzed the evaluations of the height (cm), diameter (mm) and length of the reproductive branches (cm) to determine the respective vegetative growth rates of the plants. The determined amounts of total phenols in the plants with production (17.40 µg g-1 and 13.89 µg g-1 drain and source leaves, respectively) and without coffee production (18.65 µg g-1 and 12.76 µg g-1 drain and source leaves, respectively) did not varied. However, the total phenol concentrations in new leaves of the plants with and without coffee production were greater than the amount determined in mature leaves around 25 % and 46 %, respectively. The secondary substance synthesis in the phases of expansion (16.35 µg g-1) and grain filling of the fruits (14.68 µg g-1) was 31% lower than the amounts determined in the phase of the greatest production of these substances - fruit in maturation (21.24 µg g-1). The total phenol metabolization depends indirectly on the temperature (oC) and on the global radiation (MJ m-2 day-1), presenting inverse trend in relation to these climatic variable. The orientation of the crop protection managing shall take into consideration the period when it has endangerment of the natural defense of the plant.
124

Modelagem tecnico-economica de sequestro de CO2 considerando injeção em campos maduros / A techinical-economical modeling for CO2 sequestration considering injection in mature fields

Gaspar, Ana Teresa Ferreira da Silva, 1977- 12 August 2018 (has links)
Orientador: Saul Barisnik Suslick / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica e Instituto de Geociencias / Made available in DSpace on 2018-08-12T11:55:27Z (GMT). No. of bitstreams: 1 Gaspar_AnaTeresaFerreiradaSilva_D.pdf: 2070944 bytes, checksum: abd840647c52a6c6cf1fc318f0e0a772 (MD5) Previous issue date: 2007 / Resumo: Esta tese apresenta um estudo da viabilidade técnica e econômica da Recuperação Avançada de Óleo (EOR) em um pequeno projeto localizado em um campo maduro no Brasil. O estudo considera duas motivações importantes e complementares: (1) a recuperação avançada de óleo por meio da injeção de CO2 - o gás desloca o óleo residual deixado no local após a produção primária e injeção secundária de água (waterflooding); (2) o armazenamento deste gás no reservatório de óleo e, conseqüente contribuição para a mitigação de emissões de CO2. Os aspectos físicos deste projeto são descritos e um modelo de simulação dinâmica foi desenvolvido para modelar o comportamento do sistema seqüestro de CO2 - EOR ao longo do tempo. Este modelo leva em conta os requisitos de energia para todo o processo de seqüestro de CO2 e suas respectivas emissões inerentes ao processo. Adicionalmente, uma metodologia é proposta para estimar os principais determinantes financeiros do projeto de seqüestro de CO2 (custos de compra do CO2, compressão, transporte e armazenamento) por meio de EOR. A avaliação do projeto é derivada de um modelo de fluxo de caixa, levando-se em conta o perfil de produção do reservatório, preço, custos de capital (CAPEX), custos operacionais (OPEX), créditos de CO2, depreciação, premissas fiscais etc. Um estudo de análise de sensibilidade é realizado para identificar as variáveis mais críticas. A viabilidade econômica do projeto, como esperado, é muito sensível ao preço do óleo, produção de óleo e CAPEX. Além disso, há a contribuição para a mitigação do gás de efeito estufa (GEE), armazenando uma quantidade significativa de CO2 no reservatório onde pode permanecer por milhares de anos. / Abstract: This thesis presents a technical and economic feasibility study for CO2 EOR in a small project located in a mature oilfield in Brazil. The present study considers two important and complementary motivations: (1) EOR - CO2 displaces residual oil left in place after primary production and secondary water flooding; (2) storage of this gas in the oil reservoir and hence, contributing to mitigate CO2 emissions. The physical aspects of this project are described and a dynamic simulation model has been developed in order to model the behavior of the CO2 Sequestration - EOR system and its emissions due to the process over time. This model takes into account the energy requirements for the whole CO2 sequestration process. Additionally, a breakdown cost methodology is proposed in order to estimate the main financial determinants of the integrated EOR with CO2 sequestration (costs of CO2 purchase, compression, transportation and storage). Project evaluation is derived from a cash flow model, regarding reservoir production profile, price and costs, capital expenditures (CAPEX), operating expenditures (OPEX), carbon credits, depreciation time, fiscal assumptions etc. A sensitivity analysis study is carried out in order to identify the most critical variables. Project feasibility, as expected, is found to be very sensitive to oil price, oil production, and CAPEX. Moreover, there is the contribution from the mitigation of the Green House Gas (GHG) by storing a significant amount of CO2 in the reservoir where it can remain for thousands of years. / Doutorado / Reservatórios e Gestão / Doutor em Ciências e Engenharia de Petróleo
125

Improving process efficiency : a case study / Förbättra processeffektivitet : en fallstudie

Dzamashvili, Nina January 2002 (has links)
Almost everybody in the software engineering world has read about or has heard of the importance and benefits of the mature software process. This master thesis aims to answer the question why despite all the efforts; software organizations still have difficulties to achieve the mature and effective software process. The results of the literature survey and a case study performed at a real software company have shown that there is a set of factors that may cause process inefficiency in the software companies. These factors are connected with the soft aspects of the software process such as motivation of the software engineers, process understanding and the process training. / Vad är orsakerna till att programvaruföretagen har svårt att uppnå en mogen och effektiv utvecklingsprocess? Resultatet efter en fallstudie och en literaturundersökning visar att det finns ett antal faktorer som påverkar effektiviteten på processen. / Nina Dzamashvili Övre Brunnsvägen 46, SE-372 36 RONNEBY Sweden E-mail: nina.dzamashvili@bth.se
126

A Holistic Understanding of Domestic Democratic Peace

Graetsch, Jessica January 2012 (has links)
In this study the notion of domestic democratic peace will be examined by using a holistic understanding of internal conflicts. Domestic democratic peace has most commonly been studied by using quantitative methods. This study will be qualitative using an abductive approach when understanding why mature democracies are more stable than other types of regimes. The holistic understanding of internal conflicts used in this study is based on the concepts of relative deprivation, instrumentalisation of politics and politicisation of identity. Burton’s sources of conflict are used to show how relative deprivation can be experienced. The questions to be answered in this essay are as follow: How can the proposed holistic understanding explain why mature democracies are more stable than newly established democracies and autocratic states? In what ways do mature democracies decrease experience of relative deprivation and thereby safeguarding Burton’s sources of conflict? In what ways do mature democracies cater to a more peaceful process of politicisation of identity and instrumentalisation of politics?
127

Transforming mature industries into growth industries: the case of US peanuts

Foko, Emmanuel January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Vincent R. Amanor-Boadu / For more than a decade, the consumption of peanuts as food has been stagnant. This situation has been attributed to several factors. This study seeks to identify and understand some of the factors that have hindered growth in this industry and attempts to present recommendations that will be useful in transforming the peanut industry from stability to growth. We determined that in addition to peanut prices, consumers' income and young children's share of the total population, substitute snack foods such as potatoes chips and popcorn influenced peanut consumption. We also discovered that consumer perception about peanut's fat content and the increasing concern about peanut allergies affected their consumption behavior. The research used data drawn from US Census Bureau, Department of Labor Statistics, National Agricultural Statistics Services, and various industry publications. We suggest that changing the consumption trend lines in the peanut industry can be achieved through effective innovation and focused marketing of the product's health and convenience benefits.
128

Multiplicity of roles : experiences of mature women students in a higher education setting

Mosimege, Keolebogile Betty 18 September 2007 (has links)
The purpose of this research project was to explore the experiences of mature women students in juggling the multiplicity of roles they faced during the adulthood stage of life. The lack of literature, particularly on the African woman’s experiences of being a student while also dealing with the roles of being a mother, wife and employee, inspired this research. I explored the women’s experiences using a qualitative approach and semi-structured individual interviews, and did a thematic analysis of the textual data. The average age of the women who participated in this project was 36.8, and except for two of the 10 interviewees, all women were enrolled for a postgraduate studies. The majority of women enrolled for further studies because they wanted to increase their opportunities in the work environment, while one woman did so because of a career change. The stories of the ten mature women students that I interviewed revealed five major themes. In describing their experiences of juggling multiple roles, the mature women students mentioned that they studied while also maintaining a job because of the financial obligations and the lifestyle of their age group. They experienced role strain from the many roles that required an equal share of their time, but managed to cope because they had personal goals to achieve and would not relinquish those. Both congruent and incongruent experiences emerged between work and study, particularly when they could not attribute equal time to work and study. Although they were encouraged and supported by their partners and children, and sometimes also their families and the community, they still had to deal with the lack of support from the institutions where they were enrolled. Extreme tiredness and guilt because of conflicting role demands were found to be most common among all ten women. For the most part the women had to deal with an increase in their role responsibilities and experienced different emotions regarding the influence of studying on family life. By managing their time well they were able to cope and had thus far been successful in balancing their different roles. Above all the mature women student were able to cope with the multiplicity of roles because they had determination, were focused and committed, and wanted to achieve success in their educational goals. Perseverance and dedication to their goals emerged as mature women students’ most powerful tool for coping with multiple roles. / Dissertation (MA (Psychology))--University of Pretoria, 2008. / Psychology / unrestricted
129

The artificial immune system with evolved lymphocytes

Graaff, A.J. (Alexander Jakobus) 04 July 2007 (has links)
The main purpose of the natural immune system is to protect the body against any unwanted foreign cells that could infect the body and lead to devastating results. The nature immune system has different lymphocytes to detect and destroy these unwanted foreign patterns. The natural immune system can be modeled into an artificial immune system that can be used to detect any unwanted patterns in a non-biological environment. One of the main tasks of an immune system is to learn the structure of these unwanted patterns for a faster response to future foreign patterns with the same or similar structure. The artificial immune system (AIS) can therefore be seen as a pattern recognition system. The AIS contains artificial lymphocytes (ALC) that classify any pattern either as part of a predetermined set of patterns or not. In the immune system, lymphocytes have different states: Immature, Mature, Memory or Annihilated. Lymphocytes in the annihilated state needs to be removed from the active set of ALCs. The process of moving from one state to the next needs to be controlled in an efficient manner. This dissertation presents an AIS for detection of unwanted patterns with a dynamical active set of ALCs and proposes a threshold function to determine the state of an ALC. The AIS in the dissertation uses evolutionary computation techniques to evolve an optimal set of lymphocytes for better detection of unwanted patterns and removes ALCs in the annihilated state from the active set of ALCs. / Dissertation (MSc (Computer Science))--University of Pretoria, 2007. / Computer Science / unrestricted
130

Effektiva team i projektmiljöer : En kvalitativ studie om GDQ som projektledningsverktyg för att utveckla projektteam / Efficient teams in project environments : A qualitative study exploring GDQ as an instrument to develop project teams

Jansson, Erica January 2022 (has links)
Studien syftar till att få en förståelse för Group Development Questionnaire (GDQ) som projektledningsverktyg, hur det kan användas för att utveckla team samt vad utvecklingen kan leda till hos teamen. För att besvara syftet har tre frågeställningar upprättats: Hur upplevs GDQ som verktyg? Vad underlättar användandet av GDQ vid utveckling av team? och Hur upplevs team som har utvecklats utifrån en GDQ-mätning? En kvalitativ metod med semistrukturerade intervjuer valdes för genomförandet av studien och bidrog till ett resultat med tre centrala teman: Det var väl inte så farligt, Klara, färdiga...Vilket håll ska vi åt? och Hur går det för oss?  Det var väl inte så farligt belyser vikten av information för att minska motstånd och skapa en trygghet och nyfikenhet i teamutvecklingsprocessen. Klara, färdiga... Vilket håll ska vi åt? lyfter att teamet är det centrala i teamutvecklingsprocessen och Hur går det för oss? beskriver vad teamutvecklingen med GDQ som instrument upplevs leda till hos teamen. Studiens slutsatser är att GDQ är ett bra verktyg för att skapa en insikt och medvetenhet hos teamet, men att utvecklingen sker när teamet tar tag i områdena som framkommer av GDQ-mätningen och aktivt arbetar med dem. Information, motivation och vilja hos teamet är grundläggande för att utvecklingen ska ske. Teamutvecklingen leder till mer högfungerande team, med bättre kommunikationsstrukturer och ett mer effektivt samarbete. / The purpose of this study is to get an understanding of the Group Development Questionnaire (GDQ) as an instrument for project management, how it can be used to develop teams and what the team development process may result in. To answer this, three research questions have been formulated: What is the experience of GDQ as an instrument? What facilitates the use of GDQ in the development of teams? and How are teams that have been developed using GDQ perceived? A qualitative method with semi-structured interviews was used in this study, which led to a result with three central themes: That wasn’t so bad, Ready, set... Which way are we going? and How are we doing?  That wasn’t so bad illustrates the importance of information to reduce resistance and create a feeling of safety and curiosity in the process of team development. Ready, set... Which way are we going? shows that the team is the center of the team development process and How are we doing? describes what the team development with GDQ as an instrument can lead to in teams. The conclusion of this study is that GDQ is an adequate instrument for creating a realization and awareness in teams, but the key to team development lies with the team using the information to actively work with their development. Information, communication and motivation are key elements for team development to take place. Team development using GDQ leads to higher functioning teams, with better communication structures and a more efficient collaboration.

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