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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

And Just as Far as Ever from the End: A Textual Analysis of The Gunslinger by Stephen King

Kent, Sharmin T.M. 13 January 2010 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Beginning as a collection of short stories published in The Magazine of Fantasy & Science Fiction in 1978 and novelized in 1982, The Gunslinger is the first novel in Stephen King’s Dark Tower series. This thesis explores the textual journey of the novel that serves as the foundation for a series that has left its mark throughout King’s broader fictional canon. After finishing the final three novels of the series, King revised The Gunslinger to bring it closer to the narrative essence of the series’ subsequent novels. Collation of all three versions of the text—the serialized Fantasy & Science Fiction stories, the 1982 novelization and the 2003 revised and expanded version—reveals a sometimes overlapping pattern of revisions to the novel. These revisions concentrate on character, the novel’s cosmological framework, and languages and dialects King uses later in the series. The impact of these revisions extends beyond the plot elements of the series itself, as a number of King’s most popular novels—The Stand, ’Salem’s Lot, and It among them—have plot arcs that bend toward the Dark Tower mythos. King returned to the novel’s three main characters—Roland, Jake, and the man in black—to refine their actions and clarify their motivations. This also gave him the opportunity to provide the reader with more of their interwoven histories, a strategy that established the background for the role each character plays later in the series. In addition to introducing details about the main characters of the series, King enhances and redefines the world of The Gunslinger; the revisions reveal connections both within and outside of the Dark Tower multiverse. King also uses revision to introduce a variety of languages and dialects Roland encounters on his journey through an endless path of worlds. Finally, the textual evolution of The Gunslinger documents King’s development of a theme central to his entire canon: the multifaceted theme of salvation and sacrifice. In controlling the evolution of the Dark Tower series, particularly with his return to revise The Gunslinger, Stephen King shows that he is capable of maintaining a complex saga with a great degree of literary vision and craftsmanship.
112

Techno-Economic Analysis of an Innovative Purely Solar Driven Combined Cycle System based on Packed Bed TES Technology

Ruan, Tianqi January 2019 (has links)
With increasing awareness of environmental issues and worldwide requirements for sustainable development, renewable energy technologies with lower environmental impact, especially those having abundant resources like wind and solar energy, attract more attention. Concentrating Solar Power (CSP) is one of the most promising solar energy technologies. Indeed, thermal energy storage (TES) units could be integrated into CSP plants, enhancing their flexibility and capacity factor. However, tower based CSP plants still remain cost intensive. This study evaluates the performance of a 55MWe combined-cycle CSP plant with rock-bed TES located in Sevilla, Spain. Sensitivity analysis has been performed to assess the influence of critical parameters. Furthermore, in order to decrease the costs with increasing efficiency, improved CSP plant schemes have been proposed. In the study, EES, SAM and TRNSYS are used to design and simulate the model from technological perspective, then the capital and operational costs are calculated in MATLAB. For one-year simulation of the designed case, the performance of the plant is determined by the trade-off among several conflicting factors. The study focuses on three key indicators to measure the performance- levelized costs of electricity (LCoE), capital expenditure (CAPEX) and efficiency factor (UF). As long as CAPEX is within the acceptable range, LCoE would be the most concerned one-as low as possible, then followed by UF. Compared to conventional CCGT plant, the proposed combined-cycle tower-based CSP plant, with efficiency of 0.49 and LCoE of 196USD/MWe, enables efficiency improvements, while both CAPEX and LCoE are higher. On the other hand, it has to be noticed that CCGT relies on fuel (natural gas) price, which means higher risks and operational expenditure (OPEX). A sensitivity study is involved varying gas turbine expansion ratio (to vary its outlet temperature and therefore supply power for the bottoming Rankine cycle), size of TES and solar multiple (SM). It can be found that same LCoE and UF could be achieved with lower CAPEX by setting appropriate parameters. The study also introduces two improved CSP plant schemes with sensitivity study. To some extent, the LCoE decreases due to increasing power output and the efficiency of the system simultaneously increases. / Med ökad medvetenhet om miljöfrågor och globala krav på hållbar utveckling lockar förnybar energi teknologi med lägre miljöpåverkan, särskilt de som har stora resurser som vind och solenergi, mer uppmärksamhet. Concentrating Solar Power (CSP) är en av de mest lovande solenergi teknologierna. Faktiskt kan värmeenergi lagringsenheter integreras i CSP-anläggningar, vilket förbättrar deras flexibilitet och kapacitetsfaktor. Träbaserade CSP-anläggningar är dock fortfarande kostnads intensiva. Denna studie utvärderar prestandan för en 55MWe CSP-anläggning med kombinerad cykel med TESsandbädd i Sevilla, Spanien. Känslighetsanalys har utförts för att bedöma påverkan av kritiska parametrar. För att minska kostnaderna med ökad effektivitet har dessutom förbättrade CSP-anläggningsprogram föreslagits. I studien används EES, SAM och TRNSYS för att designa och simulera modellen ur teknologiskt perspektiv, sedan beräknas kapital och driftskostnader i MATLAB. För ett års simulering av det planerade fallet bestäms anläggningens prestanda av bytet mellan flera motstridiga faktorer. Studien fokuserar på tre nyckelindikatorer för att mäta prestandanivå kostnaderna för el (LCoE), investeringar (CAPEX) och effektivitetsfaktor (UF). Så länge CAPEX ligger inom det acceptabla intervallet, skulle LCoE vara den mest bekymrade en så låg som möjligt, följt av UF. Jämfört med konventionell CCGT-anläggning möjliggör den föreslagna träbaserade CSP-anläggningen med kombinerad cykel med effektivitet 0,49 och LCoE på 196USD / MWe effektivitetsförbättringar, medan både CAPEX och LCoE är högre. Å andra sidan måste man notera att CCGT förlitar sig på bränslepriset (naturgas), vilket innebär högre risker och driftsutgifter (OPEX). En känslighetsstudie är involverad med varierande utvidgning förhållande för gasturbin (för att variera dess utloppstemperatur och därmed leverera ström för botten Rankine-cykeln), storlek på TES och sol multipel (SM). Det kan konstateras att samma LCoE och UF skulle kunna uppnås med lägre CAPEX genom att ställa in lämpliga parametrar. Studien introducerar också två förbättrade CSP-anläggningar med känslighetsstudie. I viss utsträckning minskar LCoE på grund av ökad effekt och systemets effektivitet ökar samtidigt.
113

Advancing Performance of Passive Downdraft Cooling Towers

January 2017 (has links)
abstract: Passive cooling techniques, specifically passive downdraft cooling (PDC), have proven to be a solution that can address issues associated with air conditioning (AC). Globally, over 100 buildings have integrated PDC in its different forms, most of which use direct evaporative cooling. Even though all surveyed buildings were energy efficient and cost-effective and most surveyed buildings were thermally comfortable, application of PDC remains limited. This study aims to advance performance of the single stage passive downdraft evaporative cooling tower (PDECT), and expand its applicability beyond the hot dry conditions where it is typically used, by designing and testing a multi-stage passive and hybrid downdraft cooling tower (PHDCT). Experimental evaluation on half-scale prototypes of these towers was conducted in Tempe, Arizona, during the hot dry and hot humid days of Summer, 2017. Ambient air dry-bulb temperatures ranged between 73.0°F with 82.9 percent coincident relative humidity, and 123.4°F with 7.8 percent coincident relative humidity. Cooling systems in both towers were operated simultaneously to evaluate performance under identical conditions. Results indicated that the hybrid tower outperformed the single stage tower under all ambient conditions and that towers site water consumption was at least 2 times lower than source water required by electric powered AC. Under hot dry conditions, the single stage tower produced average temperature drops of 35°F (5°F higher than what was reported in the literature), average air velocities of 200 fpm, and average cooling capacities of 4 tons. Furthermore, the hybrid tower produced average temperature drops of 45°F (50°F in certain operation modes), average air velocities of 160 fpm, and average cooling capacities exceeding 4 tons. Under hot humid conditions, temperature drops from the single stage tower were limited to the ambient air wet-bulb temperatures whereas drops continued beyond the wet-bulb in the hybrid tower, resulting in 60 percent decline in the former’s cooling capacity while maintaining the capacity of the latter. The outcomes from this study will act as an incentive for designers to consider incorporating PDC into their designs as a viable replacement/supplement to AC; thus, reducing the impact of the built environment on the natural environment. / Dissertation/Thesis / Doctoral Dissertation Architecture 2017
114

Časové posouzení využití zdvihacích mechanismů v pozemním stavitelství / Time Assessment of Lifting Mechanisms Efficiency in Civil Engineering

Štěrba, Martin Unknown Date (has links)
The dissertation thesis deals with the time assessment of designed lifting mechanisms in monolithic constructions in Civil Engineering. The main reason for choosing this subject matter is a current trend in construction that in terms of administrative and housing construction tends to build monolithic buildings. Lifting mechanisms are crucial in such buildings nowadays. The efficiency of lifting mechanisms is often neglected in the preparatory phase of construction time schedules, which leads to inefficient capacity utilization of the machine. Nevertheless, this is directly related to meeting the agreed deadlines, which in turn leads to complications that often result in a considerable financial loss for the contractor. In order to solve this subject matter it was necessary to perform monitoring on an appropriate sample of constructions. In the case of this work it was a total of six buildings, four of which were further analysed. Furthermore, individual partial construction processes requiring tower crane operation were analysed. A time assessment methodology including a proposal of possible prioritization of selected activities has been developed. Based on the knowledge gained from the monitoring of the buildings as well as from the analysis of individual items, a simulation model was developed. This model mathematically and graphically evaluates the ability of the designed tower crane to serve a given number of partial construction processes within a specified evaluation section in which the smallest evaluated section equals to one work shift. The benefit of this work is to enable efficient deployment of the tower crane in the preparatory phase of construction. Another benefit is also a prompt operative assessment of the load of the tower crane by a works foreman within a given shift. This should lead to a more efficient deployment of tower cranes during construction and as a consequence it should result in keeping the agreed terms. This is closely associated
115

Etudes dans le canal avec deux leptons de même signe de la physique du top au-delà du modèle standard / Study in the two same sign leptons channel of top beyond standard model physics with the ATLAS detector at the LHC and study of the L1 Calo Trigger

Gauthier, Léa 14 September 2012 (has links)
Le sujet de cette thèse est « L’étude dans le canal avec deux leptons de même signe de la physique du top au-delà du Modèle Standard avec le détecteur ATLAS au LHC et l’étude du niveau de déclenchement L1 du calorimètre ». Cette thèse porte sur la recherche de processus de nouvelle physique au LHC faisant jouer au quark top un rôle particulier. Le LHC est un collisionneur de protons, conçu pour un fonctionnement nominal avec une énergie dans le centre de masse de 14 TeV. Jusqu’à fin 2011 il a fonctionné avec une énergie de 7 TeV dans le centre de masse. Les premières données recueillies (5 fb−1 à 7 TeV) nous ont permis de contraindre certains paramètres de la nouvelle physique recherchée. C’est dans ce cadre que s’inscrit cette thèse. Celle-ci est divisée en trois parties. La première décrit rapidement l’accélérateur avant de s’intéresser à l’expérience ATLAS et au fonctionnement de son détecteur. Le bon fonctionnement des cartes de sommation du signal du calorimètre électromagnétique pour le premier niveau de déclenchement des événements a été tout particulièrement étudié. La deuxième partie est une analyse phénoménologique de la physique au-delà du Modèle Standard avec quatre quarks top dans l’état final pour plusieurs modèles théoriques. Cette étude a été effectuée principalement au niveau générateur pour 14 TeV dans le centre de masse mais nous commentons également les perspectives à 7 TeV. Elle peut être appliquée à l’expérience ATLAS comme à l’expérience CMS. La troisième partie est une étude expérimentale, réalisée avec le détecteur ATLAS, recherchant des manifestations d’un modèle de Higgs composite prédisant l’existence de partenaires exotiques au quark top (T5/3) et d’un modèle de théorie effective de production des 4 tops. Une limite sur la masse du partenaire exotique a été obtenue ainsi qu’une limite sur la section efficace des événements exotiques à quatre tops. / The subject of this thesis is the « Study in the two same sign leptons channel of top Beyond Standard Model Physics with the ATLAS detector at the LHC and the study of the L1 Calo Trigger ». The central subject of this thesis is the search for new physics in which the top quark plays a crucial role. The LHC is a proton collider, designed for a nominal operation with 14TeV. in the center of mass. Until december 2011 it worked with an energy of 7 TeV in the center of mass. The first 5 fb−1 of collected data allowed us to constrain some parameters of the new physics processes presented in this thesis. The document is divided into three parts : the first one describes briefly the LHC accelerator before presenting the ATLAS experiment and operation of the detector. The Tower Builder Boards for the electromagnetic level one trigger are especially studied. The second part is a phenomenological analysis of physics beyond the Standard Model with four top quarks in the final state. This analysis is presented for several theoretical models. This study was performed mainly at the generator level for 14 TeV in the center of mass but we also comments on prospects at 7 TeV. It can be applied to both ATLAS and CMS experiments. The third part is an experimental study, performed with the ATLAS detector, searching for two exotic processes with two same signe leptons in the final state (T5/3 and four tops production). A limit on the mass of the top partner T5/3 has been obtained as well as a limit on the cross section of exotic events with four tops.
116

Design of wind turbine tower and foundation systems: optimization approach

Nicholson, John Corbett 01 May 2011 (has links)
A renewed commitment in the United States and abroad to electricity from renewable resources, such as wind, along with the recent deployment of very large turbines that rise to new heights, makes obtaining the most efficient and safe designs of the structures that support them ever more important. Towards this goal, the present research seeks to understand how optimization concepts and Microsoft Excel's optimization capabilities can be used in the design of wind turbine towers and foundations. Additionally, this research expands on the work of previous researchers to study how considering the tower and foundation as an integral system, where tower support conditions are not perfectly rigid, affects the optimal design. Specifically, optimization problems are formulated and solved with and without taking into account the effect of deflections, resulting from the foundation's rotational and horizontal stiffness, on natural frequency calculations. The general methodology used to transcribe the design of wind turbine towers and foundations into an optimization problem includes: 1) collecting information on design requirements and parameter values 2) deciding how to analyze the structure 3) formulating the optimization problem 4) implementation using Microsoft Excel. Key assumptions include: 1) use of an equivalent lumped mass method for estimating natural frequency 2) International Electrotechnical Commission (IEC) 61400-1 extreme loading condition controls design (i.e. fatigue loading condition is not considered) 3) extreme loads are obtained from manufacturer provided structural load document that satisfies loading cases outlined in IEC 61400-1 4) wind forces on the tower are calculated in accordance with IEC 61400-1 5) optimization variables are continuous. The sum of the tower material and fabrication cost and the total foundation cost is taken as the objective function. Important conclusions from this work include: 1) optimization concepts and Microsoft Excel's optimization capabilities can be used to obtain reasonable conceptual level designs and cost estimates 2) detailed designs and cost estimates could be achieved using a solver capable of handling discrete optimization problems 3) considering the tower and foundation as an integral system results in a more expensive, but safer, design 4) for the assumed parameter values, the constraint on the tower's natural frequency was found to control the tower design and the bearing capacity constraint was found to control the foundation design 5) relaxing or tightening the limit on the natural frequency will result in the greatest benefit or penalty, respectively, on the optimum solution.
117

The Watch Tower movement in south central Africa, 1908-1945

Cross, Sholto January 1973 (has links)
The Watch Tower movement was a millennial social movement which was popular in Nyasaland, Southern and Northern Rhodesia, and the Belgian Congo, and in parts of the countries bordering these territories, between the two world wars. It derived its doctrine initially from the writings of Charles Russell, the founder of one of the largest sects of the twentieth century, the Jehovah's Witnesses. The African Watch Tower however was largely independent of the Jehovah's Witnesses, although this body attempted to establish its control in central Africa, and its ideology and organisation changed and developed in accordance with local conditions. While some similarities in the conditions of rapid urbanisation which surrounded the origins of the Jehovah's Witnesses in America, and the Watch Tower in Africa, may be discerned, its political and historical role was a very different one. Spread by labour migrants moving between employment centres and from the village to the urban compound, the Watch Tower contributed to the new forms of association which enabled workers to protest against their conditions of employment, and assisted in spreading a pan-Africanist consciousness which was a significant current in the development of anti-colonial nationalism. It was not only an urban movement, but also selectively influenced the countryside, where external factors and the nature of local social organisations were favourable. It spread rapidly, in a wide variety of forms, and with little formality regarding who was or was not a member, but retained a central core of ideas and an organisational structure, which allows the movement to be treated as a unity.
118

Vyhlídková věž v západních Jeseníkách / The Viewing Tower in Western Jeseníky

Nosková, Denisa January 2015 (has links)
The purpose of this thesis is to create design and static assessment of the viewing tower in western Jeseníky mountains. The Ground plan is formed by regular hexagon with outer diameter 0.8 meter. Glued laminated profiles, steel tubes and elements of solid wood were predominantly used for the construction of the building. The viewing tower has four viewing platforms and total high of the structure is 28.5 meters.
119

Stanovení výkonnosti chladicího okruhu - chladící věž / Determination of the performance of the cooling circuit - cooling tower

Velešík, Aleš January 2015 (has links)
The aim of this work is to determine the performance and description of the cooling circle in the cooling tower. In order to do that there was applied the linear regression approach in order to create structural empirical model of the cooling tower. The data obtained was analysed through QC expert software, which, if correct data applied, identifies suitable model for specific tower. The models created will be used for diagnostics of the cooling circles and as a comparison tool with other cooling towers in the future. Thus, the findings of this thesis are polynoms, which in thic technological setup characterise the models of the cooling towers.
120

Exergoeconomic Analysis and Benchmark of a Solar Power Tower with Open Air Receiver Technology

Ertl, Felix January 2012 (has links)
No description available.

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