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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.
111

Modelování parametrů spalovacích motorů

Dobrovolný, Milan January 2015 (has links)
Master thesis deals with the link between the internal and external parameters of the combustion engine. Its point is not to exactly define this links but only check if this links exist and what is their character. First part of the thesis is dedicated to present state of the mixture preparation systems of the petrol engines. Here are described the ways of the lambda regulation and its effect of the specific fuel consumption. Further are described types of injection systems and at the end is described the way for the determination of the ignition advance. Second part is focused on the chosen mathematics-statistics methods which are interesting and useful for the solving this problem. Last part is paid to the verification of the existence the links of the operating parameters and attempt of their definition in numeric way using the Maple software and chosen mathematics-statistics methods.
112

O método de divisão-e-conquista na solução de auto-sistemas de matrizes simétricas

Ceresoli, Eliamar January 2002 (has links)
O presente trabalho apresenta um estudo do método de divisão-e-conquista para solução dos auto-sistemas de matrizes tridiagonais simétricas. Inicialmente, explanamos a parte teórica, e posteriormente, por meio de exemplos numéricos mostramos seu funcionamento. Para a realização deste estudo, utilizou-se o software Maple como ferramenta auxiliar. Realizamos comparações e análises dos auto-sistemas encontrados com as rotinas DSTEDC e DSTEQR do LAPACK, que utilizam respectivamente o método de divisão-e-conquista e o método QR e também comparamos estes com os resultados encontrados por nós. Verificamos por meio de testes os tempos, que as rotinas citadas, dispendem na resolução de alguns auto-sistemas. Os resultados apresentados mostram que o método de Divisão-e-Conquista é competitivo com o método tradicional, QR, para o cálculo de autovalores e autovetores de matrizes tridiagonais simétricas.
113

SUMMER HABITAT USE BY A MAMMAL COMMUNITY OF AN OAK-DOMINATED ECOSYSTEM IN THE CENTRAL HARDWOOD REGION

Pease, Brent Steven 01 August 2017 (has links)
In the greater Central Hardwood Region, advance regeneration of oak (Quercus spp.) and hickory (Carya spp.) has been in decline for several decades. Facilitated in part by an abrupt change in disturbance regime, coupled with an increase in herbivore density, the existing mid-successional, mast-producing species are being outcompeted by late-successional, mesophytic species. Oak-hickory forests provide keystone resources for a diverse forest wildlife community, and a decline in its dominance will likely impact habitat use and occupancy patterns in the mammal community, but to what extent is unclear. During May-August 2015-2016, I deployed 150 remotely-triggered camera traps in Trail of Tears State Forest (TTSF), Union County, Illinois to investigate single-season, site occupancy patterns and detection probabilities as a function of forest composition and structure for 3 mammals (eastern gray squirrel [Sciurus carolinensis], raccoon [Procyon lotor], and white-tailed deer [Odocoileus virginianus]). I collected microhabitat data at each camera-site and utilized a GIS application to estimate spatial relationships among anthropogenic features and camera-sites. I recorded 404 photographs of 11 endothermic species during 3927 days of survey effort, with white-tailed deer, raccoons, and eastern gray squirrels as the most detected species, respectively. Detection probability of eastern gray squirrels was best explained by the global detection model, indicating no covariate measured explained the variation in detection rates. Raccoon detection probability was best described by a negative relationship with the average temperature recorded during survey period. The best-fitting detection model for white-tailed deer indicated detection probabilities declined throughout the sampling period and across seasons. Eastern gray squirrel site occupancy models received little support, however, ecological land type phase was the most supported model. The best fitting habitat model described a negative relationship between eastern gray squirrel site occupancy probability and coarse woody debris volume. For raccoons, no model with habitat covariates was better fitting than the null model. Raccoon occupancy probability increased with maximum DBH at a site, ground cover, and beech-maple importance values, but decreased with oak-hickory importance values. White-tailed deer occupancy was most positively influenced by ground cover and oak-hickory importance values, but decreased with distance to forest edge, number of understory stems, and beech-maple importance values. My research provides empirical evidence to predictions made regarding the impact of a decline in oak dominance across the Central Hardwood region on a portion of the region’s mammal community. Shifts to late-successional conditions in the Central Hardwood region will likely continue and magnify if forest management approaches continue to minimize the frequency and occurrence of large, anthropogenic disturbances to the forest overstory. A mosaic of forest conditions will be needed to best support a diverse and complete mammal community across the region.
114

O método de divisão-e-conquista na solução de auto-sistemas de matrizes simétricas

Ceresoli, Eliamar January 2002 (has links)
O presente trabalho apresenta um estudo do método de divisão-e-conquista para solução dos auto-sistemas de matrizes tridiagonais simétricas. Inicialmente, explanamos a parte teórica, e posteriormente, por meio de exemplos numéricos mostramos seu funcionamento. Para a realização deste estudo, utilizou-se o software Maple como ferramenta auxiliar. Realizamos comparações e análises dos auto-sistemas encontrados com as rotinas DSTEDC e DSTEQR do LAPACK, que utilizam respectivamente o método de divisão-e-conquista e o método QR e também comparamos estes com os resultados encontrados por nós. Verificamos por meio de testes os tempos, que as rotinas citadas, dispendem na resolução de alguns auto-sistemas. Os resultados apresentados mostram que o método de Divisão-e-Conquista é competitivo com o método tradicional, QR, para o cálculo de autovalores e autovetores de matrizes tridiagonais simétricas.
115

O método de divisão-e-conquista na solução de auto-sistemas de matrizes simétricas

Ceresoli, Eliamar January 2002 (has links)
O presente trabalho apresenta um estudo do método de divisão-e-conquista para solução dos auto-sistemas de matrizes tridiagonais simétricas. Inicialmente, explanamos a parte teórica, e posteriormente, por meio de exemplos numéricos mostramos seu funcionamento. Para a realização deste estudo, utilizou-se o software Maple como ferramenta auxiliar. Realizamos comparações e análises dos auto-sistemas encontrados com as rotinas DSTEDC e DSTEQR do LAPACK, que utilizam respectivamente o método de divisão-e-conquista e o método QR e também comparamos estes com os resultados encontrados por nós. Verificamos por meio de testes os tempos, que as rotinas citadas, dispendem na resolução de alguns auto-sistemas. Os resultados apresentados mostram que o método de Divisão-e-Conquista é competitivo com o método tradicional, QR, para o cálculo de autovalores e autovetores de matrizes tridiagonais simétricas.
116

Maple Sugar Bush Management and Biodiversity Conservation in Eastern Ontario, Canada

Clark, Kristin January 2011 (has links)
This thesis examines the extent to which sugar bush management in Eastern Ontario might contribute to biodiversity maintenance and conservation and therefore be promoted as a form of rural sustainable development. Ontario government policy seeks to actively promote actions that strengthen the province’s rural communities and protect biodiversity. Therefore sustainable development is an important concept to encourage in rural areas. The production of maple syrup on sugar bushes has already been demonstrated to be economically, socially, and in some aspects ecologically sustainable. This study seeks to determine how the operation of sugar bushes might also contribute to ecological sustainability through the maintenance and conservation of forest biodiversity. I identified three documents published by the Eastern Ontario Model Forest (EOMF): a set of management principles for conserving biodiversity on private woodlots, a list of biodiversity indicators, and a manual for monitoring them. I monitored three of the biodiversity indicators (spring ephemerals, birds, and frogs) on three of the larger sugar bushes in the Eastern Ontario and established that the EOMF biodiversity monitoring practices and guidelines were suitable for working sugar bushes. Using the management principles for biodiversity conservation developed by the EOMF, I interviewed 22 sugar bush operators in Eastern Ontario. With these interviews I addressed two objectives: 1. To generate empirical information regarding the management practices of maple sugar bush operators in Eastern Ontario and to compare these with established management principles for forest biodiversity conservation in the region 2. To generate suggestions for woodlot operators and government policymakers alike about future opportunities for research and management decision-making. The results of the study show that although most operators do not have a formal management plan for their sugar bush, many of their management practices are consistent with prescribed biodiversity conservation principles. Sugar bush operators are receptive to conserving biodiversity on their properties. The findings suggest that through sound management and planning, small-scale commercial sugar bush operations generally can be made environmentally sustainable, and become important components in broader rural development strategies. This study provides new insights into how small-scale sugar bush management, when practiced well, is consistent with conservation principles and with sustainable development principles more generally. It shows how sugar bush operators in Eastern Ontario can help the province reach its goals of biodiversity conservation and rural development set out in Ontario’s Biodiversity Strategy (2005) and Ontario’s Rural Plan (2004).
117

Kontrolní tepelný výpočet teplovodního žárotrubného kotle / Rating thermal calculation of fire tube water heater

Polášek, Kryštof January 2020 (has links)
This diploma thesis deals with thermal calculations of fire tube water heater. The first part of the thesis describes different classifications of boilers and water heaters and provides a basic overview for different types of commonly used boilers. The next part describes thermal calculation model created in Maple software, used formulas and algorithm of the model. Subsequently, the model is applied to the experimental water heater in the form of computational rating. In the last part of the thesis the model is applied to the existing operated industrial water heater to evaluate predictive ability of the calculation model by comparing the essential operating parameters obtained from the calculation with real data measured on the water heater.
118

Návrh svozové trasy odpadu s využitím algoritmů pro řešení úlohy obchodního cestujícího

Novotná, Jana January 2018 (has links)
This diploma thesis deals with the optimization of collection routes of separated waste in Velké Meziříčí. This waste is collected by the Technical Services VM s.r.o. The solution is designed using the well-known Traveling salesman problem method and the proposed algorithm is a combination of these methods. The algorithm is designed to work in the Maple algebraic system and the data were analysed using ArcGIS and Statistica. Gradual development and functionality of the algorithm is represented by resulting separate waste collection routes.
119

Maple Syrup in Appalachia: A Sustainable Economic Development Opportunity

Grizzard, Daniel Howell 22 May 2023 (has links)
Many parts of Appalachia, including areas of Virginia, West Virginia, and Maryland, lag behind much of the country in key socioeconomic indicators. There is a need for economic development opportunities that leverage the region's natural resources in a sustainable manner. This study investigates the feasibility of using maple syrup production as an economic development strategy. This study is broken into three sections, the first is a survey of current maple syrup producers to investigate how syrup is produced and sold in this region. This survey is followed by a pricing analysis that was conducted to ascertain the feasibility of small-scale producers competing with often larger and well-established Northeastern maple syrup producers. The final chapter is an economic impact analysis of the Highland County Maple Festival. This analysis was conducted to learn about the current impacts of maple syrup agritourism for producers and the communities they operate in. Findings from this study indicate that the maple syrup industry in Maryland, Virginia, and West Virginia is smaller and more localized than the industry in the Northeastern United States and Canada. However, the difference in how maple syrup is sold can provide many potential benefits for Appalachian communities. A localized approach to selling maple syrup that relies on attracting visitors to farms has the potential to create an economic stimulus for not only maple syrup producers, but also the communities in which they operate. / Master of Science / The Appalachian region of the United States has higher rates of poverty than the rest of the country. Many rural communities in Appalachia are also losing population. Due to these factors, there is a need for the development of new ways to bring money and jobs into Appalachian communities. This study investigates the potential to use maple syrup production to help stimulate economic development into central Appalachian communities in Maryland, Virginia, and West Virginia. This study is broken into three sections, the first is a survey of maple syrup producers to see how syrup is currently produced and sold in this region. This survey is followed by a pricing analysis that was conducted to see if it is possible for small-scale producers to sell their products in grocery stores. The final chapter is an economic impact analysis of the Highland County Maple Festival. This analysis was conducted to see how tourism that is focused on maple syrup impacts the communities that it takes place in. Findings from this study indicate that the maple syrup industry in Maryland, Virginia, and West Virginia is smaller and more local than the industry in the Northeastern United States and Canada. However, the difference in how maple syrup is sold can provide many potential benefits for Appalachian. A localized approach to selling maple syrup that relies on attracting visitors to farms through tourism has the potential to create an economic stimulus for not only maple syrup producers, but also the communities in which they operate.
120

Properties of four domestic hardwood species

Carmona Uzcategui, Marly Gabriela 01 May 2020 (has links)
This study aimed to evaluate the physical and mechanical properties of red oak (Quercus spp.), white oak (Quercus spp.), hard maple (Acer saccharum) and yellow-poplar (Liriodendron tulipifera) and compare them to values from past publications. Mechanical testing was conducted on small, clear, defectree specimens from red oak, white oak, hard maple and yellow-poplar following the standard ASTM D143. Percentage of latewood, moisture content, specific gravity, modulus of elasticity (MOE), modulus of rupture (MOR), compression parallel and perpendicular to the grain and Janka hardness were determined. Results indicated that mechanical properties for red oak, white oak, hard maple and yellow poplar have not changed substantially because the average values remain in a range that is very close to the ones published in past studies. Thus, values from the Wood Handbook can still be used for engineering purposes.

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