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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.
91

Wheat Price Dynamics In Turkey: A Nonlinear Analysis

Tonguc, Ozlem 01 September 2010 (has links) (PDF)
Wheat is an extremely important agricultural commodity, due to its crucial role in everyday nutrition, food security, and in terms of incomes of a large body of farmers worldwide. This study examines the dynamics of wheat prices in Turkey in a framework that allows for regime switching. Due to their simplicity, threshold autoregressive (TAR) models are used to capture the effects of factors such as transaction costs and other institutional arrangements that generate discontinuous adjustment to equilibrium price level. The results are compared with standard linear model estimations. Results indicate that there is strong evidence for asymmetric adjustment of wheat prices in Turkey to the equilibrium price, hence models allowing for regime switching are more preferable over the linear ones. However, the diagnostics of the TAR model reveal that specification of a TAR model allowing for more than two regimes, or a smooth transition autoregressive (STAR) model that allows for smooth transition through a continuum of regimes might be more appropriate.
92

The study of Correlation between Customer¡¦s Satisfaction Degree and the Entire Quality of the Coal Tar industry

Hsu, Ching-Liao 23 July 2003 (has links)
In order to gain more profit and be superior to others in an environment full of intense competitions, enterprises nowadays not only have to maintain the original product quality, price, and sale passageways but also need to enhance the service quality, in an attempt to increase customers¡¦ satisfaction degree and faithfulness degree. According to the newly published ISO 9001: 2000 Customer Satisfaction Management Structure, the priority in the operating system of quality management has become customers. As a result, one of a manager¡¦s responsibilities now includes emphasizing customers¡¦ relationship management and utilizing operating strategies, which customers are satisfied. The research, which consists of China Steel Chemical Corporation¡¦s new version of ISO 9001: 2000 Customer Satisfaction Management Structure, results from the collected references and information regarding customers¡¦ satisfaction degree, along with customers¡¦ opinions obtained from thorough meetings. It analyzes certain key factors affecting customers¡¦ satisfaction degree. The research-investigating subject is all the customers, who have purchased or used the products and enjoyed the service of China Steel Chemical Corporation during the time period from April 1st, 2002 to March 31st, 2003. Survey questionnaires are also examined to measure the customers¡¦ satisfaction level, so as to evaluate the entire quality of a series of coal tar products. In the meanwhile, in order to assist China Steel Chemical Corporation to meet the standards of ISO 9001: 2000 Customer Satisfaction Management Structure, procedures, which are deliberately used for estimating the customers¡¦ satisfaction degree index, are also established. The study eventually analyzes the relationship between the total quality of the coal tar products and the customers¡¦ satisfaction degree and the correlation between the customers¡¦ satisfaction degree and faithfulness degree. Following the construction of a scale measurement, the research discovers that the entire quality of the coal tar industry products is composed of the service quality and the original product quality, which includes products, sales, prices, communications, and product deliveries. Accordingly, the higher the entire quality of the products is, the higher the customers¡¦ satisfaction degree becomes. Moreover, the study also finds out that the higher customers¡¦ satisfaction degree significantly indicates the higher customers¡¦ faithfulness degree, for the customers will be more willing to purchase the products again as well as recommend others to buy the products. In addition, after developing the procedures to assess the product quality of the coal tar industry from a variety of aspects, the research reveals that by simply consulting the handy evaluation procedures, a manager will be able to come up with other suitable ways to resolve the customers¡¦ complaints as well as improve the product and service quality. The established system that combines information of the product quality and the customers¡¦ satisfaction degree, can effectively and completely reflect the customers¡¦ feedbacks. Thus, it indeed provides enterprises with valuable references in the process of improving the entire product quality efficiently. ¡iKey Words¡j: coal tar, customers¡¦ satisfaction degree, Customer Satisfaction Management Structure, service quality, customers¡¦ faithfulness degree
93

Thermochemical and Catalytic Upgrading in a Fuel Context : Peat, Biomass and Alkenes

Hörnell, Christina January 2001 (has links)
No description available.
94

Pyrolysis of biomass. Rapid pyrolysis at high temperature. Slow pyrolysis for active carbon preparation.

Zanzi, Rolando January 2001 (has links)
<p>Pyrolysis of biomass consists of heating solid biomass inthe absence of air to produce solid, liquid and gaseous fuels.In the first part of this thesis rapid pyrolysis of wood(birch) and some agricultural residues (olive waste, sugarcanebagasse and wheat straw in untreated and in pelletized form) athigh temperature (800ºC–1000ºC) is studied ina free fall reactor at pilot scale. These conditions are ofinterest for gasification in fluidized beds. Of main interestare the gas and char yields and compositions as well as thereactivity of the produced char in gasification.</p><p>A higher temperature and smaller particles increase theheating rate resulting in a decreased char yield. The crackingof the hydrocarbons with an increase of the hydrogen content inthe gaseous product is favoured by a higher temperature and byusing smaller particles. Wood gives more volatiles and lesschar than straw and olive waste. The higher ash content inagricultural residues favours the charring reactions. Charsfrom olive waste and straw are more reactive in gasificationthan chars from birch because of the higher ash content. Thecomposition of the biomass influences the product distribution.Birch and bagasse give more volatiles and less char thanquebracho, straw and olive waste. Longer residence time inrapid pyrolysis increase the time for contact between tar andchar which makes the char less reactive. The secondary charproduced from tar not only covers the primary char but alsoprobably encapsulates the ash and hinders the catalytic effectof the ash. High char reactivity is favoured by conditionswherethe volatiles are rapidly removed from the particle, i.e.high heating rate, high temperature and small particles.</p><p>The second part of this thesis deals with slow pyrolysis inpresence of steam for preparation of active carbon. Theinfluence of the type of biomass, the type of reactor and thetreatment conditions, mainly temperature and activation time,on the properties and the yield of active carbons are studied.The precursors used in the experiments are birch (wood) anddifferent types of agricultural residues such as sugarcanebagasse, olive waste, miscanthus pellets and straw in untreatedand pelletized form.</p><p>The results from the pyrolysis of biomass in presence ofsteam are compared with those obtained in inert atmosphere ofnitrogen. The steam contributes to the formation of solidresidues with high surface area and good adsorption capacity.The yield of liquid products increases significantly at theexpense of the gaseous and solid products. Large amount ofsteam result in liquid products consisting predominantly ofwater-soluble polar compounds.</p><p>In comparison to the stationary fixed bed reactor, therotary reactor increases the production of energy-rich gases atthe expense of liquid products.</p><p>The raw materials have strong effect on the yields and theproperties of the pyrolysis products. At equal time oftreatment an increase of the temperature results in a decreaseof the yield of solid residue and improvement of the adsorptioncapacity until the highest surface area is reached. Furtherincrease of the temperature decreases the yield of solidproduct without any improvement in the adsorption capacity. Therate of steam flow influences the product distribution. Theyield of liquid products increases while the gas yielddecreases when the steam flow is increased.</p><p><b>Keywords</b>: rapid pyrolysis, pyrolysis, wood, agriculturalresidues,biomass, char, tar, gas, char reactivity,gasification, steam, active carbon</p>
95

Threshold Cointegration with Applications to the Oil and Gasoline Industry

Mann, Janelle 19 June 2012 (has links)
This thesis develops a new methodological approach to test for threshold cointegration. It determines the threshold locations, the number of thresholds, and tests the null hypothesis of a unit root against the alternative of a stationary threshold process using p-values based on a residual-based block bootstrap for the nonlinear threshold autoregressive specification (TAR). Chapter 2 describes the methodological approach which combines Gonzalo and Pitarakis (2002) and Seo (2008). Chapter 3 employs Monte Carlo analysis to investigate the properties of the new approach. The results indicate that the methodology performs well and is suited for application to real world time series. Chapter 4 applies the new approach in combination with a threshold error correction model (ECM) to determine the spatial relationships among three crude oil prices: WTI, Brent, and Oman, from 2008 through 2011. The results indicate that the crude oil benchmarks are tied together by a long run relationship; however, the recent reversal in price premium between the two main crude oil benchmarks, WTI and Brent, is an anomaly that has resulted in a time period in which the series do not have a tendency to move back toward their long run relationship. Chapter 5 applies the new approach, in combination with threshold ECMs, with regime switches being triggered by the upstream markup margin to determine the vertical relationships between the crude oil, rack, and retail gasoline prices for six cities across North America. The results using both daily and weekly data between 2008 and 2011 suggest that upstream and downstream prices are cointegrated. There is evidence of band-TAR in which the crude, rack, and retail prices are free to diverge until the markup margin is squeezed or stretched beyond a lower or upper threshold. This suggests that abnormally high margins cannot be sustained indefinitely. The threshold ECMs indicate that there is no systematic relationship between the speed of adjustment and the markup margin; however, the residuals exhibit a leverage effect in which volatility and price changes are negatively correlated. Chapter 6 concludes with a summary of Chapters 2 through 5 and makes suggestions for future research. / Thesis (Ph.D, Management) -- Queen's University, 2012-06-17 22:53:24.922
96

Étude de l'immunité maternelle et de la diversité génétique du virus de l'immunodéficience humaine de type I (VIH-1) durant la grossesse

Akouamba, Bertine Sandra January 2008 (has links)
Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal
97

Dismantling dependency, disarming a boom: petro-politics and the staples state in an era of climate crisis

Noble, Paul 29 April 2015 (has links)
This thesis has two central objectives. First, drawing on both the insights contained in the staples approach and the frames and narratives mobilized by contemporary political actors, it attempts to provide insight into the political-economic drivers underpinning the large and growing political influence of the Canadian oil sands. Second, it assesses the effects of this influence on Canadian society and the Canadian state. This influence is observable materially, as with the federal government’s oil sands-oriented policy changes and mobilization of the state security apparatus in its defense, and in less concrete ways, as with the rise of discourses conflating national interest with continued oil sands expansion. This thesis concludes that the effects of this influence have been negative and profound, and in an era of climate crisis, alternatives to Canada’s dominant political economic trends must be urgently sought. / Graduate / paulnoblegreen@gmail.com
98

Concerto for Tar and Orchestra

Best, Robert M 16 July 2014 (has links)
The great challenge that exists in cross-cultural composition is finding commonalities of intonation, style, formality, and instrumentation. In the case of creating a composition for Persian tar and symphony orchestra, a number of challenges emerge. The goal of this composition is to find compatible musical elements between Persian and western music. The most difficult challenge of composing in this genre is finding compatible musical modes to generate optimum intonation. For this piece, the western pitch of Bb is used to help the intonation and tonal production of the tar. My approach to style involves a sensitive application using elements of classical Persian style and formality known as dãstgãh composition. Generally, Persian music places strong emphasis on improvisation, non-repetitive scalar melodies, variation of melodic and rhythmic material, tasteful ornamentation, and creating an inspiring musical atmosphere. Often music is composed with a story, poem or song in the mind of the performer. Typically, the instrumentation is very small and intimate, consisting of a tar performer, accompanied by a musician playing a daff (a Persian frame drum much like an Irish bodhran). I have composed a work that features many of the above characteristics. The Concerto for Tar and Orchestra encompasses many salient features found in Persian classical music, while also providing symphonic orchestration that adds complimentary western musical elements. Most of the instrumentation of the work adheres to standard orchestral instrumentation. I have included some Persian hand-drums to the orchestration (a tombak and a dohol) to play alongside standard symphonic percussion to add a more cross-cultural quality to the orchestration. The concerto also owes its inspiration to the story “Umar and the Harpist”, which is found in Jellaludin Rumi’s revered, masterful literary work entitled the Masnavi. I used the imagery found in this story to generate much of the dramatic contrast contained in the concerto. In the end, a composition has emerged which brings two distinct classical music traditions together in an effective cross-cultural form of expression.
99

Investigation of catalytic phenomena for solid oxide fuel cells and tar removal in biomass gasifiers

Kuhn, John N., January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 322-338).
100

"En by är ingen lagård" : en undersökning av människa/djur-relationen i Sara Lidmans Tjärdalen

Smitz, Mikael January 2015 (has links)
The intention of this study is to investigate the human/animal-relation as a power relation in Sara Lidman’s novel The Tar Pit (Tjärdalen, 1953). With regard to the contemporary theory of posthumanism and its critique of the centrality of “the human” in the humanities, the aim is to seek and produce more-than-anthropocentric knowledge. Using queer and feministic theoretical concepts concerning dichotomy and hierarchy voiced by Yvonne Hirdman, Val Plumwood, Greta Gaard and Ann-Sofie Lönngren, this study gets to grips with anthropocentrism as a structure of power. In literary scholarship animals are often expected to serve as metaphors, and thus, the possibility of animals signifying “actual” animals tend to be overlooked. This study’s objective is therefore, using a text interpretation modelled by Eve Kosofsky Sedgewick and a method proposed by Ann-Sofie Lönngren, to focus on the surface of the text. In the analysis of The Tar Pit it appears that animals is attributed “low status” in relation to the human and that the humans ascribe animals with instrumental value. The power relation between humans and animals in the novel is based on the split between “the human” and “the animal”, and also the notion that humans constitute the norm and are hierarchically superior. Furthermore the analysis show that transgressive activity between categories “human” and “animal” is illustrated as something wrong and the concept of “the animal” and “animality” is displayed as an imperative function in telling the story of The Tar Pit. Finally the analysis depicts examples of animal acts of resistance against the prevalent order of things.

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