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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Vyhodnocení návrhu protierozních a protipovodňových opatření se zaměřením na pásové střídání plodin / Evaluation of design of erosion and flood control measures focusing on the crop belt rotation

Jarová, Nicole Unknown Date (has links)
The aim of the work was to analyze the erosion and runoff conditions in the cadastral area of Ketkovice in the district of Brno. The work focuses mainly on the outflow and erosion situation, the survey of terrain, the proposal of measures with a focus on alternation of crop belt rotation and the Spatial Plan of the municipality in terms of the runoff conditions. The first part of the diploma thesis is focused on the analyze the erosion and runoff conditions. The second part is focused on creating suitable shapes of alternation of crop belt rotation in combination with grass cover and creating a suitable grass line stripe, which will allow us to drain water and increase the amount of infiltration. My work is concentrated on how to apply these measures in the right way. Each of the methods was described and the individual results of the calculations were compared with each other, and subsequently the most suitable method for the given locality was developed. I´ve determined the erosion using the Wismeier-Smith equation in the ArcGIS As far as possible, it would be appropriate to use the most effective proposals for erosion protection using suitable erosion protective means. One of the possibilities is an area measure in combination with a line measure.
2

Lowest cost building technology selection for energy efficient design

Simmons, Brian Spencer 10 December 2012 (has links)
The thesis project explores the use of an optimization methodology for selecting the lowest monetary cost combinations of technologies to meet a set operational energy efficiency targets for buildings. The optimization approach, which is operated on a normative energy model, is compared with existing prescriptive methodologies for selecting technology combinations and a metric is developed for ranking their effectiveness; the E/C Ratio. The energy savings/ cost ratio is also the objective function that the optimization algorithm is set to maximize. The optimization routine is coded in to a custom MATLAB script and is used in two case studies to optimize a proto-typical Korean apartment and office building. The optimization methodology finds technology combinations that are much more cost effective than the prescriptive methodology at meeting an energy savings target and can generically be applied to other buildings given a palette of technology alternatives and the corresponding cost data.
3

Föryngring och produktion av skog på torvmark / Forest regeneration and production on peatlands

Eriksson, Stanley, Eriksson, Anki January 2014 (has links)
Kunskapen kring svensk torvmarksbeskogning är undermålig. En kunskapslucka som till stor del beror på att torvmark tidigare bedömts som ointressant mark i samband med skogsproduktion. Detta beror mycket på det svenska regelverkets restriktioner mot markavvattning och gödsling samt miljöaspekterna som berörs och den aktivare skötsel som krävs. Det ökade behovet av skogsråvara gör att skogsbruket söker nya marker där torvmarken har potential att etableras för skogsproduktion. Studien är en kunskapssammanställning som lyfter fram kunskap kring skogsbruk på svensk torvmark med fokus på föryngringsprocessen. Finland använder torvmarker i skogsbruket på ett sofistikerat sätt. I studien jämförs Sveriges förutsättningar för skogsproduktion på torvmark med Finlands skötselprogram, en jämförelse som går att använda som en fingervisning till vilka föryngringsmetoder som lämpar sig i Sverige. Studien rymmer även en mindre fältstudie på torvmark som visar på tydliga indikationer av näringsbrist i marken och vikten av en korrekt utförd gödslingsåtgärd. / The knowledge of forestry on Swedish peatland is insufficient. The knowledge gap is largely due to peatland previously being considered unsuitable land in connection with the forest. This is highly due to the Swedish regulatory restrictions on land drainage and fertilization, but also due to the environmental aspects involved and proactive maintenance required. The increased demand for forest products has allowed forestry to seek alternatives, where peat soil has the potential to be established for forest production. The study is a compilation of knowledge that emphasizes the knowledge of forestry on Swedish peatland with focus on the rejuvenation process. Finland uses peatland forestry in a sophisticated way. The study compares Sweden's prospects for forestry on peatland with Finland's maintenance program, a comparison that can be used as a pointer to which rejuvenation methods are suitable in Sweden. The study also contains a field study on peatland showing clear signs of nutrient deficiency in the soil and the importance of correct fertilization.
4

Investigations into the effectiveness of measures to reduce the energy requirements of domestic dwellings in Cyprus

Florides, Georgios A. January 2001 (has links)
In recent years there has been an increasing trend in the provision of central heating and split vapour compression air conditioning systems to domestic dwellings in Cyprus. To minimise their economic and environmental impact, this study examines the feasibility and economic viability of energy conservation measures and the feasibility of the application of solar driven LiBr-water absorption system for space conditioning. Initially, the study compares through simulation, the heating and cooling requirements of domestic dwellings constructed in Cyprus during the last century. The simulations required values for the thermal conductivity of local building materials, like the hollow brick and mud and straw block. These were not available, and measurements were performed on a machine specifically purchased for the project to establish these values for the first time. These material properties will be of value to building services engineers in Cyprus and the Middle East for the more precise determination of building heating and cooling loads. Evaluation of the internal conditions resulting from the various types of constructions indicated that the traditional and insulated modem houses, could maintain indoor temperature in winter between 16°C and 20°C, but in the summer temperatures exceeded 36°C. The use of natural and mechanical ventilation could reduce slightly the maximum indoor summertime temperatures, but not to a level that could provide thermal comfort. Window gains are an important factor in domestic building energy requirements, and significant savings can result when extra measures are taken. The savings in cooling energy demand for a well-insulated house may be as high as 24% when low-emissivity double glazed windows are used compared to clear double glazed windows giving a pay-back period of 3.8 years. Other factors investigated are the effect of overhangs, shape and orientation of buildings and thermal mass. The results show that the roof is the most important structural element of domestic dwellings in the Cypriot environment. For good thermal performance, the roof must offer a discharge time of 6 hours or more and have a thermal conductivity of less than 0.48 W/m-K. Life cycle cost analysis has shown that measures that increase the roof insulation pay back in a short period of time, between 3.5 to 5 years. However, measures taken to increase wall insulation pay back in a longer period of time, approximately 10 years. The only natural energy resource abundantly available in Cyprus is solar energy, which could be used to power a low energy active cooling system based on the absorption cycle. To facilitate investigation of the feasibility of the application of solar driven absorption systems for domestic cooling, a 1 kW LiBr-water absorption-cooling unit was designed and constructed. The unit was used to determine experimentally the heat and mass transfer coefficients in the heat exchangers of absorption systems. In certain cases these were found to differ considerably from values obtained from heat and mass transfer correlations published by other investigators. The experimentally determined heat and mass transfer coefficients were employed in the design and costing of an 11 kW cooling capacity solar driven absorption cooling machine which, from simulations, was found to have sufficient capacity to satisfy the cooling needs of a well insulated domestic dwelling. Economic analysis has shown that for such a system to be economically competitive compared to conventional cooling systems its capital cost should be below C£ 2000. This drawback can be balanced by a lower total equivalent warming impact being 2.7 times smaller compared to conventional cooling systems.
5

Effekten av naturvärdesgynnande åtgärder på fågelfaunan : En vinterfågelinventering i Tjäderbergets mångfaldspark / The effects of conservation measures on bird fauna : A winter bird inventory in Tjäderbergets diversity park

Rashid, Kadhim January 2020 (has links)
Increasingly homogenous forest landscapes, with fewer occurrences of wildfires, deciduous trees and dying, decaying wood has led to fewer appropriate habitats and feeding opportunities for several forest dwelling species, including birds. This study sought to assess the species richness, diversity, and evenness of winterbirds in forest stands where conservation methods (planting of alder trees, free development, burning of forest stands and promotion of deciduous dominance) have been applied, as well as a managed stand of lodgepole pine (Pinus contorta), within SCA:s Tjäderbergets diversity park. These stands were compared with managed stands of Scots pine (Pinus sylvestris). Bird species composition was collected by performing regular 25-minute inventories in each stand type at 5 time periods daily over a 6-day period in late March, 2020. Significant differences in species richness was discovered between a stand of free development and the managed stands as well as a stand treated for deciduous dominance and the managed stands. There were no significant differences with regard to neither species diversity between the observed stand types, nor the presence of specialists or generalists. Evenness between the stand types showed little variation. These results may be due to the overall low number of unique species and individuals in each stand type which likely resulted from low statistical power of the statistical tests. Further research into the effects of conservation measures in forests stands on bird fauna are needed to obtain conclusive results on how conservation measures affect local bird assemblages.
6

SCREENING METHODOLOGY FOR PRIORITIZING ENERGY CONSERVATION MEASURES FOR OFFICE BUILDING STOCKS

Perry, Heather Lynn 10 1900 (has links)
<p>As energy costs continue to escalate and awareness spreads with regard to the importance of sustainability, interest in reducing energy consumption of buildings is growing. For managers of large stocks of office buildings, the task of selecting building improvement projects is most challenging. A multitude of energy conservation measures (ECMs) are available from which to select, however financial resources are limited and in high demand. Thus, ECMs must be known to be effective and prioritized so as to provide the highest benefit for the financial resources available.</p> <p>The aim of this study is to provide a screening methodology for the evaluation and prioritization of ECMs for implementation in a stock of buildings that exhibit varying characteristics and locations. Prioritization of ECMs is based on predicted energy consumption savings and financial analysis. Building stocks are reduced to a manageable set by applying archetype classification. Energy consumption predictions for representative buildings from each archetype are obtained through use of a mathematical model. Twelve ECMs pertaining to improvements in the building envelope, HVAC, and electrical systems are considered and ranked based on present value over the short, mid, and long terms.</p> / Master of Applied Science (MASc)
7

Kuwait Residential Energy Outlook: Modeling the Diffusion of Energy Conservation Measures

January 2019 (has links)
abstract: The residential building sector accounts for more than 26% of the global energy consumption and 17% of global CO2 emissions. Due to the low cost of electricity in Kuwait and increase of population, Kuwaiti electricity consumption tripled during the past 30 years and is expected to increase by 20% by 2027. In this dissertation, a framework is developed to assess energy savings techniques to help policy-makers make educated decisions. The Kuwait residential energy outlook is studied by modeling the baseline energy consumption and the diffusion of energy conservation measures (ECMs) to identify the impacts on household energy consumption and CO2 emissions. The energy resources and power generation in Kuwait were studied. The characteristics of the residential buildings along with energy codes of practice were investigated and four building archetypes were developed. Moreover, a baseline of end-use electricity consumption and demand was developed. Furthermore, the baseline energy consumption and demand were projected till 2040. It was found that by 2040, energy consumption would double with most of the usage being from AC. While with lighting, there is a negligible increase in consumption due to a projected shift towards more efficient lighting. Peak demand loads are expected to increase by an average growth rate of 2.9% per year. Moreover, the diffusion of different ECMs in the residential sector was modeled through four diffusion scenarios to estimate ECM adoption rates. ECMs’ impact on CO2 emissions and energy consumption of residential buildings in Kuwait was evaluated and the cost of conserved energy (CCE) and annual energy savings for each measure was calculated. AC ECMs exhibited the highest cumulative savings, whereas lighting ECMs showed an immediate energy impact. None of the ECMs in the study were cost effective due to the high subsidy rate (95%), therefore, the impact of ECMs at different subsidy and rebate rates was studied. At 75% subsidized utility price and 40% rebate only on appliances, most of ECMs will be cost effective with high energy savings. Moreover, by imposing charges of $35/ton of CO2, most ECMs will be cost effective. / Dissertation/Thesis / Doctoral Dissertation Mechanical Engineering 2019
8

Comparison of underwater visual methods for assessing temperate rocky reef fish communities and the effectiveness of spatial marine conservation areas

Burke, Lily Anne-Marie 04 September 2018 (has links)
Precise and accurate species abundance and distribution data are important for making effective ecological conservation and management decisions. These data are often challenging to obtain, especially in marine environments where the logistical and technical difficulties of working underwater can limit the precision and accuracy of detection. The chosen survey methodology, along with the study design, will determine the extent to which species’ spatial or temporal variability in abundance and distribution may be investigated. Different observational methods may yield different results. I explore how the methodology used to collect sample measurements of fish abundance and diversity in marine environments can influence your understanding of the focal population and the effectiveness of spatial marine conservation measures. I compare inshore rockfish abundance and fish diversity estimates between paired towed video and baited video surveys and between dive and baited video surveys conducted on temperate rocky-reefs in the nearshore Northeast Pacific on the coast of British Columbia, Canada. I test if the baited video survey data yield equivalent insight to those data derived from the methods commonly used in shallow (dive surveys) and deeper waters (towed video surveys). Paired dive and baited video surveys took place inside and outside of spatial marine conservation areas designated for inshore rockfish called Rockfish Conservation Areas. I test whether the baited video data generate the same conclusions about Rockfish Conservation Area effectiveness as data derived from the dive surveys, and whether the Rockfish Conservation Areas have greater inshore rockfish abundance and fish diversity than paired locations outside the conservation areas. I find similar inshore rockfish abundance estimates between towed and baited video, but baited video surveys detect a greater number of unique species than the towed video surveys. The dive surveys detect greater inshore rockfish abundance and fish diversity than the baited video surveys, but the baited video data yield equivalent insight on Rockfish Conservation Area effectiveness to data derived from the dive surveys. I find little evidence that inshore rockfish recovery is influenced by Rockfish Conservation Area protection. When data were combined across all sites sampled, Rockfish Conservation Areas did not produce more inshore rockfish, bigger rockfish, or greater fish diversity than paired sites outside of Rockfish Conservation Areas, whether measured using a dive survey or a baited video survey. However, I did observe a positive effect of Rockfish Conservation Area protection for some of the individual Rockfish Conservation Areas surveyed that rated as having a high Conservation Score. This suggests certain Rockfish Conservation Areas may be effective conservation areas for inshore rockfish recovery. The differences I observe in inshore rockfish abundance and fish diversity between the paired surveys reveals the methodology used can influence species abundance and diversity estimates. Baited video surveys are a low cost and effort methodology that can be used to examine inshore rockfish abundance and fish diversity over rocky reefs from nearshore waters down to depths greater than 20 m, and to monitor the effectiveness of spatial marine conservation areas. / Graduate
9

A meta para o sistema de áreas protegidas no Bioma Pampa : como estamos e para onde vamos?

Palazzi, Giovanna January 2018 (has links)
As áreas protegidas são consideradas pilares para estratégias de conservação da diversidade biológica. Presume-se que a distribuição destas áreas representa a proteção de espécies e ecossistemas. Dentre as 20 metas globais para a redução da perda de biodiversidade, a Meta 11 de áreas protegidas estabelece, dentre outros aspectos, que 17% das áreas terrestres devem ser cobertas por sistemas de áreas protegidas ecologicamente representativos, efetivos, conectados e integrados a paisagens terrestres mais amplas. Neste estudo avaliou-se a representatividade ecológica, a efetividade e a integração a paisagens mais amplas do sistema de unidades de conservação, e perspectivas para subsidiar a sua ampliação no bioma Pampa. Além das unidades de conservação stricto senso, em parte das análises também foram considerados os sistemas complementares de terras indígenas e mecanismos de preservação em propriedades rurais definidos pela Lei de Proteção da Vegetação Nativa. A avaliação da representatividade foi feita considerando o Pampa (nível nacional) e também os 11 sistemas ecológicos presentes no bioma (nível regional). Foram levantadas 53 unidades de conservação no Pampa, com cobertura total de 3,23% do bioma Os mecanismos de preservação em propriedades rurais têm potencial de ampliar o sistema de áreas protegidas para até 9,64%, porém ainda depende de validação do órgão ambiental. O percentual protegido por unidades de conservação nos sistemas ecológicos variou entre 0% e 17,76%, sendo que nove dos 11 sistemas possuem menos de 3% em unidades de conservação. Os dados indicaram que as unidades são relativamente efetivas, pois 64% delas mantiveram ou recuperaram sua cobertura de vegetação nativa. As análises sugerem ainda, que a efetividade associada à cobertura vegetal no interior das unidades possui uma relação com a dinâmica no seu entorno. De forma geral, as unidades sofrem influência das alterações no uso da terra em suas adjacências. Para manutenção da efetividade da unidade de conservação, a unidade deve ser manejada considerando essas influências do entorno. Na perspectiva de ampliação do sistema, o esforço para conservação deve ser centrado na criação de novas unidades de conservação e diversificação de categorias. Os dados aqui obtidos indicam que o Pampa dificilmente alcançará a meta de 17% em um sistema de áreas protegidas ecologicamente representativo até 2020. / Protected areas are considered cornerstones for biodiversity conservation strategies. It is presumed that the distribution of these areas represents the protection of species and ecosystems. Among the 20 global targets for reducing biodiversity loss, Target 11 establishes that 17% of land areas must be covered by ecologically representative, effective and connected systems integrated to wider terrestrial landscapes, among other aspects. This study assessed ecological representativeness, effectiveness, and integration of protected area system, into wider landscapes of the Pampa biome. Perspectives to subsidize protected area expansion were also considered here. The representativeness assessment was made by considering the Pampa (national level) and also the 11 ecological systems present in the biome (regional level). Complementary systems of indigenous lands and mechanisms of preservation in rural properties defined by the Law of Protection of Native Vegetation was considered for the national level. Fifty-three protected areas were found in Pampa, with a total coverage of 3.23% of the biome Preservation mechanisms on rural properties have the potential to extend Pampa protected area system to up to 9.64%, but still depend on the environmental agencies validation. The percentage protected by protected areas in ecological systems ranged from zero to 17.76%, and nine of the 11 systems have less than 3% in protected areas. Data indicated that protected areas are relatively effective since 64% of them maintained or recovered their native vegetation cover. Data also indicated that protected area effectiveness has a relation to the dynamics in its surroundings regarding land use and vegetation cover. It is possible to affirm that Pampa protected areas are influenced by changes in land use in their vicinity. Protected areas must be managed considering these environmental influences to maintain their effectiveness. In perspective of expansion of the protected area system, the effort for conservation should be centered on the establishment of new protected areas with the diversification of management categories and in ecological systems with low percentages of protected areas cover. Data obtained here indicates that Pampa is unlikely to reach the 17% target in an ecologically representative protected area system by 2020.
10

A meta para o sistema de áreas protegidas no Bioma Pampa : como estamos e para onde vamos?

Palazzi, Giovanna January 2018 (has links)
As áreas protegidas são consideradas pilares para estratégias de conservação da diversidade biológica. Presume-se que a distribuição destas áreas representa a proteção de espécies e ecossistemas. Dentre as 20 metas globais para a redução da perda de biodiversidade, a Meta 11 de áreas protegidas estabelece, dentre outros aspectos, que 17% das áreas terrestres devem ser cobertas por sistemas de áreas protegidas ecologicamente representativos, efetivos, conectados e integrados a paisagens terrestres mais amplas. Neste estudo avaliou-se a representatividade ecológica, a efetividade e a integração a paisagens mais amplas do sistema de unidades de conservação, e perspectivas para subsidiar a sua ampliação no bioma Pampa. Além das unidades de conservação stricto senso, em parte das análises também foram considerados os sistemas complementares de terras indígenas e mecanismos de preservação em propriedades rurais definidos pela Lei de Proteção da Vegetação Nativa. A avaliação da representatividade foi feita considerando o Pampa (nível nacional) e também os 11 sistemas ecológicos presentes no bioma (nível regional). Foram levantadas 53 unidades de conservação no Pampa, com cobertura total de 3,23% do bioma Os mecanismos de preservação em propriedades rurais têm potencial de ampliar o sistema de áreas protegidas para até 9,64%, porém ainda depende de validação do órgão ambiental. O percentual protegido por unidades de conservação nos sistemas ecológicos variou entre 0% e 17,76%, sendo que nove dos 11 sistemas possuem menos de 3% em unidades de conservação. Os dados indicaram que as unidades são relativamente efetivas, pois 64% delas mantiveram ou recuperaram sua cobertura de vegetação nativa. As análises sugerem ainda, que a efetividade associada à cobertura vegetal no interior das unidades possui uma relação com a dinâmica no seu entorno. De forma geral, as unidades sofrem influência das alterações no uso da terra em suas adjacências. Para manutenção da efetividade da unidade de conservação, a unidade deve ser manejada considerando essas influências do entorno. Na perspectiva de ampliação do sistema, o esforço para conservação deve ser centrado na criação de novas unidades de conservação e diversificação de categorias. Os dados aqui obtidos indicam que o Pampa dificilmente alcançará a meta de 17% em um sistema de áreas protegidas ecologicamente representativo até 2020. / Protected areas are considered cornerstones for biodiversity conservation strategies. It is presumed that the distribution of these areas represents the protection of species and ecosystems. Among the 20 global targets for reducing biodiversity loss, Target 11 establishes that 17% of land areas must be covered by ecologically representative, effective and connected systems integrated to wider terrestrial landscapes, among other aspects. This study assessed ecological representativeness, effectiveness, and integration of protected area system, into wider landscapes of the Pampa biome. Perspectives to subsidize protected area expansion were also considered here. The representativeness assessment was made by considering the Pampa (national level) and also the 11 ecological systems present in the biome (regional level). Complementary systems of indigenous lands and mechanisms of preservation in rural properties defined by the Law of Protection of Native Vegetation was considered for the national level. Fifty-three protected areas were found in Pampa, with a total coverage of 3.23% of the biome Preservation mechanisms on rural properties have the potential to extend Pampa protected area system to up to 9.64%, but still depend on the environmental agencies validation. The percentage protected by protected areas in ecological systems ranged from zero to 17.76%, and nine of the 11 systems have less than 3% in protected areas. Data indicated that protected areas are relatively effective since 64% of them maintained or recovered their native vegetation cover. Data also indicated that protected area effectiveness has a relation to the dynamics in its surroundings regarding land use and vegetation cover. It is possible to affirm that Pampa protected areas are influenced by changes in land use in their vicinity. Protected areas must be managed considering these environmental influences to maintain their effectiveness. In perspective of expansion of the protected area system, the effort for conservation should be centered on the establishment of new protected areas with the diversification of management categories and in ecological systems with low percentages of protected areas cover. Data obtained here indicates that Pampa is unlikely to reach the 17% target in an ecologically representative protected area system by 2020.

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