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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.
61

The adoption of advanced feed-in tariffs in Ontario : a case of institutional layering

Fontaine, Jacques 07 1900 (has links)
En mai 2009, l’Ontario a adopté la Loi sur l’énergie verte et devint ainsi la première juridiction en Amérique du Nord à promouvoir l’énergie renouvelable par le biais de tarifs de rachat garantis. En novembre 2010, dans son Plan énergétique à long terme, la province s’est engagée à déployer 10,700 MW en capacité de production d’énergie renouvelable non-hydroélectrique par 2018. Il s’agit de la cible de déploiement la plus élevée dans ce secteur au Canada. Les infrastructures de production et de distribution d’électricité comprennent des coûts d’installation élevés, une faible rotation des investissements et de longs cycles de vie, facteurs qui servent habituellement à ancrer les politiques énergétiques dans une dynamique de dépendance au sentier. Depuis le début des années 2000, cependant, l’Ontario a commencé à diverger de sa traditionnelle dépendance aux grandes centrales hydroélectriques, aux centrales à charbon et aux centrales nucléaires par une série de petits changements graduels qui feront grimper la part d’énergie renouvelable dans le mix énergétique provincial à 15% par 2018. Le but de ce mémoire est d’élucider le mécanisme de causalité qui a sous-tendu l’évolution graduelle de l’Ontario vers la promotion de l’énergie renouvelable par le biais de tarifs de rachat garantis et d’une cible de déploiement élevée. Ce mémoire applique la théorie du changement institutionnel graduel de Mahoney et Thelen au cas du développement de politiques d’énergie renouvelable en Ontario afin de mieux comprendre les causes, les modes et les effets du changement institutionnel. Nous découvrons que le contexte canadien de la politique énergétique favorise la sédimentation institutionnelle, c’est-à-dire un mode changement caractérisé par de petits gains favorisant l’énergie renouvelable. Ces gains s’accumulent pourtant en transformation politique importante. En Ontario, la mise sur pied d’une vaste coalition pour l’énergie renouvelable fut à l’origine du changement. Les premiers revendicateurs de politiques favorisant l’énergie renouvelable – les environnementalistes et les premières entreprises d’approvisionnement et de service en technologies d’énergie renouvelable – ont dû mettre sur pied un vaste réseau d’appui, représentant la quasi-totalité de la société ontarienne, pour faire avancer leur cause. Ce réseau a fait pression sur le gouvernement provincial et, en tant que front commun, a revendiqué l’énergie renouvelable non seulement comme solution aux changements climatiques, mais aussi comme solution à maints autres défis pressants de santé publique et de développement économique. La convergence favorable d’un nombre de facteurs contextuels a certes contribué à la réussite du réseau ontarien pour l’énergie renouvelable. Cependant, le fait que ce réseau ait trouvé des alliés au sein de l’exécutif du gouvernement provincial s’est révélé d’importance cruciale quant à l’obtention de politiques favorisant l’énergie renouvelable. Au Canada, les gouvernements provinciaux détiennent l’ultime droit de veto sur la politique énergétique. Ce n’est qu’en trouvant des alliés aux plus hauts échelons du gouvernement que le réseau ontarien pour l’énergie renouvelable a pu réussir. / In May 2009, Ontario adopted the Green Energy and Green Economy Act and became the first jurisdiction in North America to promote renewable energy through advanced feed-in tariffs. In November 2010, in its Long-Term Energy Plan, the province pledged to deploy 10,700 MW of non-hydroelectric renewable energy capacity by 2018, the highest such target in Canada. Electricity production and distribution infrastructure is characterized by high setup costs, low capital stock turnover and long life spans, factors that traditionally entrench energy policy in path-dependent trajectories. Since the early 2000’s, however, Ontario has diverged from its historic reliance on large hydro, coal and nuclear through a series of gradual policy shifts set to expand renewable energy’s share in the overall supply mix to 15% by 2018. The purpose of this thesis is to uncover the causal mechanism behind Ontario`s gradual shift toward the promotion of renewable energy through advanced feed-in tariffs, accompanied by high deployment targets. The thesis applies Mahoney & Thelen’s theory of gradual institutional change to the case of renewable energy policy development in Ontario, providing new insight into the causes, modes and effects of institutional change. The thesis finds that the Canadian energy policy context favors a layering pattern of change, characterized by small, yet cumulative, renewable energy policy gains. The driving force of this process involves coalition building. To achieve renewable energy policy gains, Ontario`s first renewable energy proponents, mostly environmental groups and early renewable energy supply and service firms, had to build a wide-ranging, multi-stakeholder network of allies and lobby government from a unified front, presenting renewable energy as a solution not only to climate change but a combination of other immediately pressing public health and economic challenges. Elements of timing greatly aided the renewable energy network’s campaign. Ultimately, however, the thesis finds that, given provincial governments` ultimate veto power over energy policy, finding allies in the top echelons of government was most crucial to the renewable energy network`s success.
62

Archaeological methodology and art making : excavating parallels

Simonis, Esther Malan 30 November 2006 (has links)
See file 01 / Art History, Visual Arts and Music / (M.A. (Visual Arts))
63

Relação da condutividade elétrica aparente com algumas propriedades físico-hídricas e com a variabilidade espacial dos solos / Apparent electrical conductivity relationship with some physical properties and spatial variability in soils

Leandro Maria Gimenez 03 December 2013 (has links)
A variabilidade das propriedades físicas do solo apresenta impacto sobre o desempenho das atividades de produção agrícola. Métodos indiretos para obtenção de informações sobre as propriedades do solo com interesse agronômico são utilizados com o intuito de favorecer o uso de insumos de modo mais adequado. A condutividade elétrica aparente do solo (CEa) é influenciada por diversas propriedades, muitas delas interrelacionadas e com variabilidade em curta distância, sendo difícil a separação dos diversos fatores. As medidas de CEa são usualmente tomadas em superfície com arranjos de eletrodos para prospecção de um volume de solo proporcional à distância entre eles. Neste trabalho foi utilizada uma metodologia que permitiu identificar algumas das propriedades com maior impacto sobre a CEa, merecendo destaque aquelas relacionadas ao espaço poroso do solo. A caracterização detalhada da variação da CEa ao longo do perfil do solo e sua comparação com aquela obtida a partir da sondagem elétrica vertical permitiram identificar algumas limitações desta técnica. A presença de camadas com variação de diversas propriedades físicas e de umidade no perfil do solo alterou os valores observados em superfície. A relação entre a distância de separação dos eletrodos no arranjo com quatro pontas igualmente espaçadas, e a profundidade de prospecção, coeficiente k, oscilou entre 0,35 e 0,70 para os solos LVd, LAd e PVe avaliados. A sondagem elétrica empregada na caracterização de variabilidade espacial na horizontal e em profundidade em uma área com teores de argila oscilando entre 150 e 379 g kg-1 na camada 0 a 0,2 m e entre 225 e 326 g kg-1 na camada 0,6 a 0,8 m apresentou resultado satisfatório. / The variability of soil physical properties has an impact on the performance of agricultural production activities. Indirect methods for obtaining information on the soil properties with agronomic interest are used to allow the use of inputs more appropriately. The apparent soil electrical conductivity ( ECa ) is influenced by several properties , many of them interrelated and presenting variability in short distances, being difficult to separate the various factors. ECa measures are usually taken in surface, using electrode arrangements for prospecting a soil volume proportional to the distance between them. In this work, a methodology was used that identified some of the properties with the greatest impact on the ECa, with emphasis to those related to soil porous space. The detailed characterization of the variation of ECw throughout the soil profile and its comparison with that obtained from the vertical electrical sounding was carried to identify certain limitations of this technique. The presence of several layers with varying physical properties and moisture in the soil profile changed values obtained from surface sounding. The relationship between the separation of the electrodes in the array with four points equally spaced, the Wenner array, and the depth of exploration, coefficient k, ranged between 0.35 and 0.70 for the soils LVd , LAd PVe and evaluated. A survey was done for the ECa characterization of spatial variability in the horizontal and along soil profile in an area with clay content ranging from 150 to 379 g kg - 1 in the layer from 0 to 0.2 m and between 225 and 326 g kg - 1 in layer 0, 6 to 0.8 m. The use of ECa for characterizing this variability showed satisfactory results.
64

A Palaeoproterozoic high-sulphidation epithermal gold deposit at Orivesi, southern Finland

Kinnunen, A. (Aulis) 06 May 2008 (has links)
Abstract The metamorphosed Palaeoproterozoic Orivesi gold deposit in southern Finland is located within the Tampere Schist Belt, which belongs to the Svecofennian domain. The Orivesi mine, run by Outokumpu Mining Oy, was in production from 1994 to 2003, during which time a total of approximately 1.7 million tons of ore was extracted, with an Au content of 9.31 g/t, implying a total output 13.115 tons of gold in concentrate. The hydrothermal alteration halo can be divided successively into chlorite-dominant, sericite-dominant and quartz-dominant rocks from the outer zone inwards. The host rocks of the ore are quartz rocks with andalusite-rich quartz rocks. Topaz-bearing rocks also occur in the inner part of the alteration halo. In addition to Au, the elements Ag, Te, Bi, Sb, S, As, Se, Cu, Zn, Pb, Sn and Mo are enriched to varying degrees within the alteration halo. The main ore minerals include base metal sulphides, sulphosalts and tellurides. Pyrite is the most common sulphide. The sulphosalts are represented by tetrahedrite, bournonite, boulangerite and meneghinite. The most common gold, gold-silver and silver tellurides are calaverite, montbrayite, petzite, kostovite, sylvanite and hessite. Other known tellurides include tellurobismuthite, altaite, melonite, frohbergite, tsumoite, tetradymite and rucklidgeite. Gold occurs mostly in fine-grained native grains containing an average of 5% Ag. The native gold is usually of very small grain size, generally < 20 µm. Most of the gold grains in the deposit occur as intergrowths with tellurides. The adjacent hypabyssal intrusion is an obvious source of both hydrothermal fluids and metals. A comb quartz layering has been discovered in the transition zone between the intrusion and the alteration halo. The Orivesi deposit is thought to belong to the high-sulphidation epithermal type. Soon after its formation the deposit encountered deformation and metamorphism that amounted to lower amphibolite facies conditions. The subsequent retrograde metamorphism caused the reappearance of some hydrothermal minerals typical of high-sulphidation epithermal deposits.
65

Lagerbaserade och förprocesserade ljud : En undersökning av hur två implementationsmetoder påverkar uppfattningen av distans av ljud i spel / Layered sounds and pre-processed sounds : A study on how two different methods of audio implementation affect the perceived distance of sounds in games

Sorribes Bernhard, Pablo January 2017 (has links)
Undersökningens syfte var att jämföra två implementationsmetoder för ljud i spel. Dessa metoder är en lagerbaserad metod och en förrenderad metod. I den lagerbaserade metoden kombineras de olika ljudlager som ljudeffekten består av i realtid av spelmotorn, där den individuellt för varje lager applicerar volym- och filtreringskurvor över distans. I den förrenderade metoden har dessa ljudlager redan i förväg kombinerats ihop i en enda audiofil, d.v.s. att den enda behandlingen som sker i ljudmotorn är att volymen sänks över distans, på hela ljudeffekten. I bakgrunden beskrivs övergripande teorier kring perceptionen av ljud över distans och olika lyssningssätt. Även den lagerbaserade ljudmotorn Sound-O-Matic (Double Trouble Audio, 2016) beskrivs kort. Frågeställningen utvärderades genom en prototyp och en nätenkät. Prototypen bestod av ett spel med de två implementationsmetoderna, uppdelade i två versioner: Version A = Förrenderad metod Version B = Lagerbaserad metod Respondenterna spelade båda versionerna av ljudimplementationen och skulle i vardera Version gissa på avståndet och riktningen av gevärsskott som avfyrades runt dem. Resultaten tyder på att den förrenderade metoden i Version A med fördel kan användas i spel, då majoriteten av respondenterna föredrog den före Version B.
66

Le fard comme médium, objet d'étude et d'expérimentation plastique. / Makeup as a medium, object of study and plastic experimentation

Lecomte, Sophie 11 May 2011 (has links)
Le fard est une composition dont l’application sur la peau donne à celle-ci plus d’éclat ou masque un défaut physique. Accusé de tromper, instrument futile ou diabolique auquel fut comparée la peinture, le fard se définit par sa fonction mais ne s’y réduit pas. L’observation de trois vidéos permet d’étudier le fard en tant qu’il est matière colorée et conduit à déterminer ses propriétés spécifiques et les possibilités plastiques qu’elles véhiculent.Cette recherche vise à établir les modalités d’une relation entre le fard, la couleur, et le corps support au travers d’expériences plastiques filmées pour le caractériser ensuite comme médium à partir d’une pratique personnelle. / Makeup is a composition which when applied to the skin gives it more brightness or hides a physical defect. Accused of cheating, a futile or diabolical instrument, which paint has been compared, make-up is defined by its function but has lost nothing through this.The plastic arts experience allows study of make-up because it is colored and this helps determine its specific properties and plastic possibilities.This research aims to establish the details of a relationship between makeup, color and the body, using several videos to characterize it as a medium based on personal practice.
67

A cross-layer approach for optimizing the efficiency of wireless sensor and actor networks

Kohlmeyer, Eckhard Bernhard 25 June 2009 (has links)
Recent development has lead to the emergence of distributed Wireless Sensor and Actor Networks (WSAN), which are capable of observing the physical environment, processing the data, making decisions based on the observations and performing appropriate actions. WSANs represent an important extension of Wireless Sensor Networks (WSNs) and may comprise a large number of sensor nodes and a smaller number of actor nodes. The sensor nodes are low-cost, low energy, battery powered devices with restricted sensing, computational and wireless communication capabilities. Actor nodes are resource richer with superior processing capabilities, higher transmission powers and a longer battery life. A basic operational scenario of a typical WSAN application follows the following sequence of events. The physical environment is periodically sensed and evaluated by the sensor nodes. The sensed data is then routed towards an actor node. Upon receiving sensed data, an actor node performs an action upon the physical environment if necessary, i.e. if the occurrence of a disturbance or critical event has been detected. The specific characteristics of sensor and actor nodes combined with some stringent application constraints impose unique requirements for WSANs. The fundamental challenges for WSANs are to achieve low latency, high energy efficiency and high reliability. The latency and energy efficiency requirements are in a trade-off relationship. The communication and coordination inside WSANs is managed via a Communication Protocol Stack (CPS) situated on every node. The requirements of low latency and energy efficiency have to be addressed at every layer of the CPS to ensure overall feasibility of the WSAN. Therefore, careful design of protocol layers in the CPS is crucial in attempting to meet the unique requirements and handle the abovementioned trade-off relationship in WSANs. The traditional CPS, comprising the application, network, medium access control and physical layer, is a layered protocol stack with every layer, a predefined functional entity. However, it has been found that for similar types of networks with similar stringent network requirements, the strictly layered protocol stack approach performs at a sub-optimal level with regards to network efficiency. A modern cross-layer paradigm, which proposes the employment of interactions between layers in the CPS, has recently attracted a lot of attention. The cross-layer approach promotes network efficiency optimization and promises considerable performance gains. It is found that in literature, the adoption of this cross-layer paradigm has not yet been considered for WSANs. In this dissertation, a complete cross-layer enabled WSAN CPS is developed that features the adoption of the cross-layer paradigm towards promoting optimization of the network efficiency. The newly proposed cross-layer enabled CPS entails protocols that incorporate information from other layers into their local decisions. Every protocol layer provides information identified as beneficial to another layer(s) in the CPS via a newly proposed Simple Cross-Layer Framework (SCLF) for WSANs. The proposed complete cross-layer enabled WSAN CPS comprises a Cross-Layer enabled Network-Centric Actuation Control with Data Prioritization (CL-NCAC-DP) application layer (APPL) protocol, a Cross-Layer enabled Cluster-based Hierarchical Energy/Latency-Aware Geographic Routing (CL-CHELAGR) network layer (NETL) protocol and a Cross-Layer enabled Carrier Sense Multiple Access with Minimum Preamble Sampling and Duty Cycle Doubling (CL-CSMA-MPS-DCD) medium access control layer (MACL) protocol. Each of these protocols builds on an existing simple layered protocol that was chosen as a basis for development of the cross-layer enabled protocols. It was found that existing protocols focus primarily on energy efficiency to ensure maximum network lifetime. However, most WSAN applications require latency minimization to be considered with the same importance. The cross-layer paradigm provides means of facilitating the optimization of both latency and energy efficiency. Specifically, a solution to the latency versus energy trade-off is given in this dissertation. The data generated by sensor nodes is prioritised by the APPL and depending on the delay-sensitivity, handled in a specialised manor by every layer of the CPS. Delay-sensitive data packets are handled in order to achieve minimum latency. On the other hand, delay-insensitive non critical data packets are handled in such a way as to achieve the highest energy efficiency. In effect, either latency minimization or energy efficiency receives an elevated precedence according to the type of data that is to be handled. Specifically, the cross-layer enabled APPL protocol provides information pertaining to the delay-sensitivity of sensed data packets to the other layers. Consequently, when a data packet is detected as highly delay-sensitive, the cross-layer enabled NETL protocol changes its approach from energy efficient routing along the maximum residual energy path to routing along the fastest path towards the cluster-head actor node for latency minimizing of the specific packet. This is done by considering information (contained in the SCLF neighbourhood table) from the MACL that entails wakeup schedules and channel utilization at neighbour nodes. Among the added criteria, the next-hop node is primarily chosen based on the shortest time to wakeup. The cross-layer enabled MACL in turn employs a priority queue and a temporary duty cycle doubling feature to enable rapid relaying of delay-sensitive data. Duty cycle doubling is employed whenever a sensor node’s APPL state indicates that it is part of a critical event reporting route. When the APPL protocol state (found in the SCLF information pool) indicates that the node is not part of the critical event reporting route anymore, the MACL reverts back to promoting energy efficiency by disengaging duty cycle doubling and re-employing a combination of a very low duty cycle and preamble sampling. The APPL protocol conversely considers the current queue size of the MACL and temporarily halts the creation of data packets (only if the sensed value is non critical) to prevent a queue overflow and ease congestion at the MACL By simulation it was shown that the cross-layer enabled WSAN CPS consistently outperforms the layered CPS for various network conditions. The average end-to-end latency of delay-sensitive critical data packets is decreased substantially. Furthermore, the average end-to-end latency of delay-insensitive data packets is also decreased. Finally, the energy efficiency performance is decreased by a tolerable insignificant minor margin as expected. The trivial increase in energy consumption is overshadowed by the high margin of increase in latency performance for delay-sensitive critical data packets. The newly proposed cross-layer CPS achieves an immense latency performance increase for WSANs, while maintaining excellent energy efficiency. It has hence been shown that the adoption of the cross-layer paradigm by the WSAN CPS proves hugely beneficial with regards to the network efficiency performance. This increases the feasibility of WSANs and promotes its application in more areas. / Dissertation (MEng)--University of Pretoria, 2009. / Electrical, Electronic and Computer Engineering / unrestricted
68

Predicting forest strata from point clouds using geometric deep learning

Arvidsson, Simon, Gullstrand, Marcus January 2021 (has links)
Introduction: Number of strata (NoS) is an informative descriptor of forest structure and is therefore useful in forest management. Collection of NoS as well as other forest properties is performed by fieldworkers and could benefit from automation. Objectives: This study investigates automated prediction of NoS from airborne laser scanned point clouds over Swedish forest plots.Methods: A previously suggested approach of using vertical gap probability is compared through experimentation against the geometric neural network PointNet++ configured for ordinal prediction. For both approaches, the mean accuracy is measured for three datasets: coniferous forest, deciduous forest, and a combination of all forests. Results: PointNet++ displayed a better point performance for two out of three datasets, attaining a top mean accuracy of 46.2%. However only the coniferous subset displayed a statistically significant superiority for PointNet++. Conclusion: This study demonstrates the potential of geometric neural networks for data mining of forest properties. The results show that impediments in the data may need to be addressed for further improvements.
69

Testování částí oděvu pomocí tepelného manekýna / Measurement of clothing sets by means of thermal manikin

Hanzlík, Martin January 2017 (has links)
This diploma thesis is focused on the experimental determination of thermal resistance of the gloves and their combination in the layering system. The measurement was based on procedure specified in the standard ČSN EN 511 by means of thermal manikin. The thesis begins with the description of heat transfer mechanisms, description of glove materials and measurement methodology. The body of paper consists of the measured data analysis and equation design for determination of the glove layering system thermal resistance. At the end of the thesis, these equations are evaluated and it has been shown, that the thermal resistance of glove layering system cannot be precisely determined by the calculation, and it is necessary to measure the whole three-layer system.
70

Návrh a analýza rámu silničního kola z kompozitního materiálu / Design and analysis of the road bike made from composite material

Dvořáková, Barbora January 2020 (has links)
This diploma thesis is focused on the design and analysis of road bike frame made of composite material. The thesis is divided into two parts. In the first part, there is a research focused on the usage of composite materials in relation to making bike frames. The main emphasis is placed on fiber composites, which are most common in cycling. Manufacturing process and production technology are discussed. The aim of the second part is design and the numerical simulation of frame in relation to stand-ard, which is used for the testing of frames. Rigidity and strength are evaluated. The final frame is obtained from the initial design due to several iterations. In conclusion, results are evaluated and recommendations for future work are given.

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