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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.
21

The Balanced Scorecard during the early stages of a tech firm : A multiple case study regarding performance management in Swedish tech startups

Llorach, Carlos, Ottosson, Emanuel January 2016 (has links)
The rapid advances in technology and increase of tech investments across all the industries have promoted the emergence of several startups. Unfortunately, not all startups succeed despite of having good initial ideas. One reason to the poor business performance could be a lack of managerial control. Researchers and industry experts believe that performance management could support tech entrepreneurs to monitor and control the drivers that promote growth and their success. However, there is a lack of studies that could support these thoughts about its suitability for tech startups. Therefore, this study gathers empirical findings from Swedish tech startups as well as industry experts to discuss this issue. The findings show that a performance measurement system such as the Balanced Scorecard is a suitable practice for tech entrepreneurs. It also brings some insights about how the performance measurements evolve as the firms mature.
22

Valorisation de lisier de porc dans une plantation de saules à croissance rapide

Cavanagh, Annie 02 1900 (has links)
Le but de cette étude est de mieux comprendre l’effet d’une fertilisation en lisier de porc sur la productivité d’une plantation de saule tout en évaluant les risques d’impact négatif sur l’environnement. Nous avons évalué la réponse des plants à des quantités croissantes de lisiers en plus de la comparer à celle d’une fertilisation minérale. Nous avons aussi vérifié l’impact du lisier sur les teneurs nutritionnelles du sol ainsi que sur les concentrations en nitrates et phosphore de la solution du sol. Bien que l’azote du lisier soit moins efficace que celui des engrais minéraux, les résultats de notre étude montrent que le lisier est un bon engrais pour les plantations de saules. En effet, les rendements sur deux ans des parcelles ayant reçu les quantités croissantes de lisier étaient de l’ordre de 30,3 à 32,9 t/ha. Nous avons observé l’augmentation des teneurs en nitrate, cuivre et zinc dans le sol en fonction des apports croissants de lisier. Ces teneurs ont d’ailleurs diminué lors de la deuxième saison de croissance, ce qui pourrait être dû au prélèvement par les saules. Les concentrations printanières des eaux de lysimètres indiquent que la quantité maximale de lisier telle que testée lors de nos essais comporte un certain facteur de risque de lessivage des nitrates. Nous n’avons pas analysé la solution du sol des parcelles fertilisées avec des quantités plus faibles de lisier, mais nous pouvons croire qu’elles auraient induit des concentrations en nitrate comportant moins de risque de lessivage tout en assurant une productivité considérable. / The aim of this study is to investigate the effect of the use of pig slurry as fertilizer on the productivity of a willow plantation, while evaluating the risk of a negative impact on the environment. We evaluated plant response to increasing slurry amounts and compared this response to the effect of mineral fertilization. We also verified the impact of slurry on soil nutritional content as well as on nitrate and phosphorus concentrations in the soil. Although slurry nitrogen was less efficient than mineral fertilizer, the results of our study show that slurry constitutes an effective fertilizer for willow plantations. In fact, yields over two years on plots that received increasing amounts of slurry were on the order of 30.0 to 32.9 t/ha. We observed an increase in soil levels of nitrates, copper and zinc as a function of increasing slurry amounts. These levels actually decreased during the second growing season, possibly due to uptake by the willows. Springtime concentrations of water in lysimeters indicated that the maximum amount of slurry tested in our experiments was accompanied by a certain risk of nitrates leaching into the soil. We did not analyze the soil solution of plots fertilized with lower amounts of slurry, but it seems likely that these nitrate concentrations would have had a lower risk of leaching while still ensuring considerable productivity.
23

Efficacité d'espèces ligneuses en symbiose mycorhizienne arbusculaire pour la phytoremédiation d'un site urbain contaminé

Bissonnette, Laurence January 2009 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
24

Mapování podmínek pro vytváření klastrů využívajících místní obnovitelné zdroje energie v regionech / Surveying Conditions for the Creation of Clusters Making full use of Local Renewable Resources in various Regions

Macková, Eva January 2009 (has links)
My thesis deals with a creating of conditions, which limit or implicate the creation of clusters focused on exploitation of renewable energy in regions. The theoretical part is focused on general issues of clusters, especially their definition, financing and last but not least their function. One part is focused on renewable energy, biomass and the cultivation of fast-growing trees. The thesis also deals with the economic aspects of production of the fast-growing trees. The target of my thesis is to sketch the demandingness of the project and to verify if this project is realizable from the economic aspect. The practical part of my thesis is focused on creating principles and rules for the cultivation of fast-growing trees. This part analyses the summary of revenues, costs and their total appreciation. The final part of my thesis evaluates relevant risks of this project and possible recommendations for the implementation of the successful strategy.
25

Estimativa da biomassa de lenho em povoamentos de Eucalyptus grandis baseada em estatísticas do perfil de dossel geradas por escaneamento a laser aerotransportado / Stem biomass estimation of a Eucalyptus grandis plantation based on canopy height profile statistics generated by airborne laser scanning

Silva, Andre Gracioso Peres da 18 June 2014 (has links)
Este trabalho contribui para a evolução dos métodos que lidam com a quantificação de biomassa em plantações florestais em grande escala. Mais especificamente, explora o potencial de novos métodos baseados em sistemas de escaneamento a laser aerotransportado (ALS) que produzem uma representação 3D da estrutura vertical e horizontal acima do solo em plantios de Eucalyptus spp. A abordagem assume que a biomassa acima do solo pode ser estimada de forma precisa quando o perfil vertical da altura do dossel e a área basal são bem conhecidos. Assim, quatro questões foram analisadas: (i) se a função de densidade probabilidade Weibull com dois parâmetros (escala ? e forma ?) consegue descrever com precisão a distribuição vertical de pontos gerada pela tecnologia ALS e gerar um perfil aparente de altura de dossel adequado em plantios de eucalipto; (ii) se quando gerada por tecnologia ALS, a proporção de retornos no subdossel e solo tem relação significativa e positiva com a variável área basal; (iii) qual a qualidade da predição de área basal e de biomassa seca de lenho quando são usadas como variáveis explicativas um percentil baixo de altura da nuvem ALS e o parâmetro de escala da distribuição Weibull ajustada para definir o perfil vertical do dossel; e (iv) qual a qualidade dos mapas de biomassa de lenho de plantios de eucaliptos quando produzidos a partir de dois métodos diferentes, um de interpolação de dados das parcelas de campo (krigagem ordinária) e outro que usa a nuvem de pontos ALS para calibrar as informações das parcelas de campo (regressão linear). Os resultados mostraram que a função Weibull de dois parâmetros ajustou com precisão adequada o perfil das alturas do plantio de eucalipto. Do ponto de vista prático, esse resultado reforça as estratégias de uso dos parâmetros da função Weibull (escala e forma) como métricas que caracterizam adequadamente a estrutura vertical dos povoamentos florestais. A estimativa de área basal em função da proporção de retornos no subdossel e no solo mostrou-se moderada (R² = 0.42 e rRMSE = 7.6%), sendo necessários mais estudos que investiguem essa relação. As predições de área basal e biomassa do lenho foram aprimoradas em função do parâmetro ? da função Weibull, usado como estimador de escala para as alturas do dossel (área basal, R² = 0.77 e rRMSE = 4.8% e biomassa do lenho, R² = 0.89 e rRMSE = 5.1%). As variáveis, percentil 30 e parâmetro de forma (?) da função Weibull, também produziram boas estimativas (R² = 0.82 para área basal e R² = 0.93 para biomassa de lenho). Os mapas de predição de biomassa de lenho mostraram-se mais precisos quando derivados a partir de dados ALS (rRMSE = 5.5% versus 12.7% na interpolação por krigagem ordinária). / This work contributes to the evolution of methods dealing with the quantification of biomass in large-scale forest plantations. More specifically, it explores the potential of new methods based on airborne laser scanning systems to produce a 3D representation of the vertical and horizontal structure of above ground Eucalyptus spp plantations. The approach assumes that above ground biomass can be precisely estimated when the vertical profile of canopy heights and basal area are well known. Thus, four questions are examined: (i) can the Weibull probability density function (pdf) with two parameters (? scale and ? shape) describe accurately the vertical distribution of points generated by the ALS technology and generate an adequate apparent profile of canopy heights for the eucalyptus plantation?; (ii) when generated by the ALS technology, is the proportion of understory returns to ground returns significantly and positively related with basal area?; (iii) how well are basal area and dry stem biomass predicted by models using low height percentile values of the ALS point cloud and the scale parameter of the Weibull distribution describing the vertical canopy profile?; and (iv) how accurate are stem biomass maps of the eucalyptus plantation when two different methods are used, one based on interpolation that uses sample plots information (ordinary kriging) and another that uses the ALS point cloud to calibrate the sample plot information (linear regression)? The results showed that the Weibull pdf with two parameters fitted with adequate accuracy the plantation\'s height profiles. From a practical standpoint, this result reinforces the strategies of using the Weibull parameters (scale and shape) as metrics that adequately characterize the vertical structure of forest stands. Basal area estimates derived from the proportion of understory and ground returns presented only moderated accuracy (R² = 0.42 e rRMSE = 7.6%) and more research is needed to investigate such relationship. Good results were obtained when basal area and stem biomass were fitted as a function of the Weibull ? parameter, as a proxy for the scale of canopy heights (basal area, R² = 0.77 e rRMSE = 4.8%, and stem biomass, R² = 0.89 and rRMSE = 5.1%). The explanatory variables percentile 30 and the Weibull shape parameter (?) also produced good estimates (R² = 0.82 for basal area and R² = 0.93 for stem biomass). Stem biomass prediction maps showed to be more accurate when derived from ALS data (rRMSE = 5.5% against 12.7% derived from ordinary kriging interpolation).
26

Estudo de parâmetros populacionais de plantios clonais de Eucalyptus spp. a partir de nuvens de pontos obtidos com escaneamento a laser aerotransportado / Study of population parameters from clonal Eucalyptus spp. plantation using point clouds obtained with airborne laser scanning

Laranja, Danitiele Cristina França 11 July 2016 (has links)
As florestas plantadas contribuem para o desenvolvimento econômico, social e ambiental brasileiro, e o setor florestal busca plantios cada vez mais produtivos e melhor aproveitados. A tecnologia a laser aerotransportada (ALS - Airborne Laser Scanning), capaz de gerar informações tridimensionais precisas em extensas áreas e em pequeno intervalo de tempo, tem se destacado nas aplicações florestais, sendo utilizada na quantificação e caracterização de florestas. Neste estudo foram utilizados dados ALS obtidos em dois sobrevoos (2013 e 2014), cobrindo uma área de plantio do gênero Eucalyptus com diferentes clones e idades, localizada no estado de São Paulo. Esta dissertação é dividida em três partes. A primeira buscou avaliar a combinação de métricas ALS e de dupla amostragem nas estimativas de volume e na redução da intensidade amostral, comparando seus resultados aos de métodos amostrais tradicionais. Os resultados mostraram que a dupla amostragem obteve o menor erro de amostragem dentre os delineamentos, permitindo a redução do esforço amostral. A segunda parte visou caracterizar as diferenças estruturais existentes entre clones de eucalipto, com diferentes idades, a partir de métricas ALS e perfis de altura do dossel (CHP). O estudo mostrou que é possível distinguir a estrutura do dossel dos clones, o que pode contribuir com melhorias nas estimativas e no gerenciamento dos plantios comerciais. Na última parte, foram avaliados dois algoritmos de detecção de árvores individuais quanto à quantificação dos indivíduos e os efeitos da composição (tamanho de célula e filtragem) do modelo digital de alturas (CHM) no desempenho desses algoritmos. Verificou-se que as características do CHM influenciam na detecção. A estratégia com melhor desempenho resultou em um erro médio relativo de 11% no número de indivíduos. / Planted forests contribute to the economic, social and environmental development of Brazil, and the forest industry aims to increase productivity and the efficient use of these plantations. Airborne Laser Scanning (ALS) technology, capable of generating accurate three-dimensional information, covering large areas in a short time, has highlighted potential in forestry applications and has been applied in forests quantification and characterization. In this study, ALS data were obtained from two flights (2013 and 2014), covering a Eucalyptus plantation area with different clones and ages, in the state of São Paulo. This thesis comprises three parts. The first study aimed to evaluate the combination of ALS metrics and double sampling design for volume estimates and reducing sampling intensity, comparing the results to traditional sampling methods. Results showed that the double sampling had the lowest error from the designs, allowing the reduction of the sampling effort. The second part was proposed to characterize the structural differences between Eucalyptus clones with different ages, based on metrics ALS and canopy height profiles (CHP). The study showed that it is possible to distinguish the canopy structure of the clones, which can contribute to improvements in estimates and management of commercial plantations. In the last study, two individual tree detection algorithms were evaluated for quantification of individuals, and the effect of the canopy height model (CHM) composition at the performance of these algorithms was analyzed. It was found that the CHM characteristics influence the tree detection. The strategy with better performance resulted in an average relative error of 11% in number of trees.
27

Avaliação do potencial das formigas como vetores mecâncios de micobactérias em hospital especializado na assistência de pacientes de tuberculose no Estado de São Paulo / Evaluation of ants as potential mechanical vectors of mycobacteria in a hospital specializing in assistance to TB patients, the state of São Paulo

Couceiro, Ana Paula Macedo Ruggiero 02 April 2012 (has links)
Introdução - A urbanização desencadeia inúmeros transtornos, como a disseminação de artrópodes e, conseqüentemente, de doenças veiculadas pelos mesmos. As formigas são muito adaptáveis e se beneficiam com a convivência humana. Nos hospitais, elas podem ser vetores mecânicos de inúmeras bactérias, e a diversidade de espécies encontradas nestes ambientes, causam preocupação pelo risco potencial à saúde pública. O aumento das infecções hospitalares envolvendo micobactérias ambientais, com surtos no Brasil entre 1998 a 2009 em 23 estados alarmou os órgãos e profissionais de saúde pública. Objetivos - Avaliar o potencial de formigas como vetores de micobactérias em um hospital especializado no atendimento de doentes com tuberculose. Métodos - Foram realizadas seis coletas de formigas em diferentes áreas do hospital no período de 2009 a 2010, que foram semeadas em meios de cultura de Löwenstein-Jensen e de Stonebrink para isolamento de micobactérias. As culturas sugestivas foram submetidas à coloração de Ziehl-Neelsen para bacilos álcool-ácido resistentes e identificação por métodos moleculares (PRA para o gene hsp65 com o par de primers TB11 e TB12 gênero-específico e sequenciamento genético do DNA). Resultados - Do total de 247 amostras de formigas coletadas e semeadas, 70 por cento das formigas pertenciam à espécie Tapinoma melanocephalum, 25 por cento a espécie Dorymyrmex sp., 3 por cento a espécie Camponotus sp. e 2 por cento a espécie Pheidole sp., dados similares foram observados anteriormente em pesquisas realizadas em hospitais. Quinze amostras apresentaram bacilos álcool-ácido resistentes de crescimento rápido. Nos métodos moleculares, doze pertenciam ao Gênero Mycobacterium. No PRA-hsp 65, e no sequenciamento genético do DNA, quatro amostras foram identificadas quanto à espécie (duas Mycobacterium chelonae, uma Mycobacterium parafortuitum e uma Mycobacterium murale), quatro micobactérias com resultados idênticos no PRA e não identificadas no sequenciamento foram sugestivas de uma nova espécie, e duas amostras não foram identificadas. Mycobacterium chelonae isolada nesta pesquisa foi previamente descrita como agente causador de abscessos em humanos. Conclusão - Estes dados confirmam a presença de micobactérias veiculadas por formigas no ambiente hospitalar, representando um potencial vetor mecânico destas para pacientes e profissionais de saúde, principalmente em infecções nosocomiais / Introduction- Urbanization triggers numerous disorders, such as the dissemination of arthropods and, consequently, dissemination of diseases transmitted by them. Some ant species are very adaptable to the human environment. At hospitals, once they are mechanical vectors of bacteria, and the diversity of species found in these environments, they can represent a potential risk to public health. The increase of nosocomial infections involving environmental mycobacteria, with outbreaks in Brazil from 1998 to 2009 in 23 states called the interest of health professionals and health agencies. Purpose - Evaluate the potential of ants as vectors of mycobacteria in a hospital specialized in the care of patients with tuberculosis. Methods Samples of ants were collected from different areas of the hospital from 2009 to 2010, and workers were inoculated in Löwenstein-Jensen and Stonebrink media for mycobacteria isolation. The suggestive cultures were subjected to Ziehl-Neelsen stain for acid-fast bacilli and identification were performed by molecular methods (PRA for the hsp65 gene with the pair of primers TB11 - TB12 and genetic sequencing). Results - The total of 247 samples of ants collected and sown, 70 per cent belonged to species of ants Tapinoma melanochepalum, 25 per cent Dorymyrmex sp.,3 per cent Camponotus sp. and 2 per cent Pheidole sp., data similar with previous studies conducted in hospitals. Fifteen fast-growing mycobacteria were isolated. In molecular methods, twelve belonged to the genus Mycobacterium. In PRA-hsp65, and the genome sequencing of DNA, four samples were identified at species level (two Mycobacterium chelonae, one Mycobacterium parafortuitum and one Mycobacterium murale), four mycobacteria with similar results in the PRA and not identified in the sequencing, suggestive of a new species and two unidentified samples. M. chelonae was previously reported as causative agent of abscess in humans. Conclusions - These results confirm the presence of mycobacteria carried by ants in the hospital, representing a potential mechanical vector for these patients and healthcare professionals, particularly in nosocomial infections
28

Modelling Seawater Desalination With Waste Incineration Energy Using Dynamic Systems Approach

Udono, Ken, n/a January 2006 (has links)
Water shortage issues have been growing concerns in many cities around the world in recent years, especially in Eastern cities of Australia, which is the driest continent on the earth. The aim of this PhD thesis is a development of a model to study the use of waste incineration energy supplemented by alternative energy to power seawater desalination. It is to aid the freshwater supply of a drought stricken city in Eastern Australia. My work contributes to a development of efficient model in a simpler understandable way to reduce efforts required for modelling complex multi domain problems. This research is motivated by the successive severe drought conditions that affected many Australian cities in the past few years, compounded with an additional strain from a fast growing population. While we dump our waste into the Australian landscape, in more densely populated cities in Europe and Asia, the waste is incinerated to obtain thermal energy for various purposes. The waste is used as an energy source while at the same time reducing the amount of space needed for landfill. Seawater desalination has been uccessfully practiced for quite some time particularly in the Middle Eastern countries. To deal with increasing water shortage crisis, many cities around the world have opted or are considering seawater desalination to supplement their freshwater supply. The combination of both - waste incineration and seawater desalination - has rarely been studied. This is a twofold problem that requires modelling the problem of water demand and supply together with waste incineration to find a sustainable solution. This is a complex task. The effort needed for this can be reduced by using a modelling approach that is more efficient than the traditionally used statistical approaches. In this thesis, I present a comprehensive model developed using a dynamic system approach combined with artificial neural networks. It simulates water demand and supply as well as the possible amount of the desalinated water that can be produced using the energy from clean city waste incineration. This is done while taking in various influential factors including population growth and irregular weather patterns. This research comprises a literature review on seawater desalination and waste incineration, the establishment of water demand and supply dynamics of Gold Coast City as my case study and identifying any modelling difficulties that need to be overcome. This is followed by the development of a comprehensive model and its components, model calibration and simulation experiments. It was found that with the energy of waste incineration, up to 60% of the freshwater demand could be fulfilled by seawater desalination in a sustainable way.
29

Entwicklung eines Ertragsschätzers für Kurzumtriebsbestände aus Pappel / Construction of a yield estimation model for short rotation forestry with poplar

Hartmann, Kai-Uwe 20 December 2010 (has links) (PDF)
Bisherige Verfahren zur Ertragsbestimmung von schnellwachsenden Baumarten im Kurzumtrieb sind entweder mit einem hohen Zeit- und Arbeitsaufwand verbunden und/oder haben destruktiven Charakter. Die vorliegende Arbeit beschäftigt sich mit der Entwicklung eines leicht anwendbaren, zerstörungsfreien und übertragbaren Ertragsschätzers für Kurzumtriebsbestände aus Pappel. Grundlage bildet die Standardisierung von Biomassefunktionen auf deren Basis ein standort- und klonunabhängiges Modell hergeleitet wird, das eine hinreichend genaue Schätzung des Biomassevorrates gestattet. Die Untersuchungen zu Grundlagen der Modellentwicklung und der Test verschiedener Modellansätze erfolgen auf der Basis von Korrelations- und Regressionsanalysen, Signifikanztests und Varianzanalysen. Die Prüfung der Schätzgenauigkeit basiert auf fünf Evaluierungskenngrößen. Für die Anwendung des klonunabhängigen, für Alter ≥ 3 Jahre und Bestandesdichten ≤ 25000 N/ha einsetzbaren Ertragsschätzers sind lediglich drei einfach und schnell zu erhebenden Ertragsgrößen (hm, N, dg) notwendig. Innerhalb der Modellgrenzen betragen die relativen maximalen Abweichungen zwischen Real- und Schätzwerten höchstens +/- 40 % und lässt sich der Biomassevorrat mit einer durchschnittlichen Differenz (Bias) von 7,1 % schätzen.
30

Valorisation de lisier de porc dans une plantation de saules à croissance rapide

Cavanagh, Annie 02 1900 (has links)
Le but de cette étude est de mieux comprendre l’effet d’une fertilisation en lisier de porc sur la productivité d’une plantation de saule tout en évaluant les risques d’impact négatif sur l’environnement. Nous avons évalué la réponse des plants à des quantités croissantes de lisiers en plus de la comparer à celle d’une fertilisation minérale. Nous avons aussi vérifié l’impact du lisier sur les teneurs nutritionnelles du sol ainsi que sur les concentrations en nitrates et phosphore de la solution du sol. Bien que l’azote du lisier soit moins efficace que celui des engrais minéraux, les résultats de notre étude montrent que le lisier est un bon engrais pour les plantations de saules. En effet, les rendements sur deux ans des parcelles ayant reçu les quantités croissantes de lisier étaient de l’ordre de 30,3 à 32,9 t/ha. Nous avons observé l’augmentation des teneurs en nitrate, cuivre et zinc dans le sol en fonction des apports croissants de lisier. Ces teneurs ont d’ailleurs diminué lors de la deuxième saison de croissance, ce qui pourrait être dû au prélèvement par les saules. Les concentrations printanières des eaux de lysimètres indiquent que la quantité maximale de lisier telle que testée lors de nos essais comporte un certain facteur de risque de lessivage des nitrates. Nous n’avons pas analysé la solution du sol des parcelles fertilisées avec des quantités plus faibles de lisier, mais nous pouvons croire qu’elles auraient induit des concentrations en nitrate comportant moins de risque de lessivage tout en assurant une productivité considérable. / The aim of this study is to investigate the effect of the use of pig slurry as fertilizer on the productivity of a willow plantation, while evaluating the risk of a negative impact on the environment. We evaluated plant response to increasing slurry amounts and compared this response to the effect of mineral fertilization. We also verified the impact of slurry on soil nutritional content as well as on nitrate and phosphorus concentrations in the soil. Although slurry nitrogen was less efficient than mineral fertilizer, the results of our study show that slurry constitutes an effective fertilizer for willow plantations. In fact, yields over two years on plots that received increasing amounts of slurry were on the order of 30.0 to 32.9 t/ha. We observed an increase in soil levels of nitrates, copper and zinc as a function of increasing slurry amounts. These levels actually decreased during the second growing season, possibly due to uptake by the willows. Springtime concentrations of water in lysimeters indicated that the maximum amount of slurry tested in our experiments was accompanied by a certain risk of nitrates leaching into the soil. We did not analyze the soil solution of plots fertilized with lower amounts of slurry, but it seems likely that these nitrate concentrations would have had a lower risk of leaching while still ensuring considerable productivity.

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