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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.
11

The Lisle Followship as a method of group education for democracy.

McCormick, Mary Jane 01 January 1942 (has links) (PDF)
No description available.
12

Estudio genético de la mineralización de fluorita del yacimiento Puerto San Antonio (Río Negro)

Luna, Liliana Inés 28 March 2012 (has links)
La fluorita es un mineral común en la Argentina y se presenta mayormente en yacimientos existentes en la región central del país y norte de Patagonia; se utiliza en las industrias siderúr-gica y química principalmente. El objetivo de esta tesis es determinar la génesis del yacimiento de fluorita Puerto San Antonio, ubicado al NE del Macizo Nordpatagónico, provincia de Río Negro, Argentina. La mineralización se halla alojada en una falla transcurrente de azimut 59 y está constituida por una veta principal y varias subparalelas. La roca de caja de la mineralización está compuesta por tobas, areniscas tobáceas e ignimbritas riolíticas del Complejo Marifil de edad mesojurásica. La depositación, desarrollada a lo largo de seis estadios, estuvo marcada por abruptos cambios en las carac-terísticas de los fluidos con episodios de brechación. La mine-ralización es de fluorita acompañada por calcita, baritina, cal-cedonia y cuarzo. Las brechas están formadas por clastos an-gulosos y redondeados de roca de caja o fluorita de estadios anteriores rodeados por varias capas de fluorita y calcedonia principalmente formando escarapelas. Fluidos altamente sobre-saturados con alta tasa de flujo depositaron fluorita fibrosa, mientras que con baja tasa se formaron agregados de partícu-las coloidales precipitando fluorita porcelana. Frentes inesta-bles de precipitación depositaron fluorita bandeada con con-centración de los elementos que producen las anomalías de color en la base de cada capa. Estos mismos cambios se observan en bordes y/o centro de cristales, como así también en el paso de la forma octaédrica a cúbica y en líneas de cre-cimiento en los cristales. Variaciones rápidas en la temperatura y pH de los fluidos están determinadas por la presencia de fluorita granular con hábitos cúbico, octaédrico y dodecaé-drico coexistiendo. Calcita lamelar precipita en el estadio 2, durante la etapa inicial de ebullición, como consecuencia de la rápida pérdida de CO2 pero a medida que la misma se sostiene en el tiempo, el efecto que domina es la caída de la tempera-tura con respecto de la pérdida de CO2, por lo cual el carbo-nato es reemplazado por cuarzo y escasa adularia. Luego se forman romboedros de calcita producto de la presencia de complejos con SO4 2+ en la solución. Un aumento en la al-calinidad del medio produce el alargamiento del pinacoide en calcita del estadio 5. Las estructuras de los minerales del gru-po de la sílice reflejan cambios mineralógicos y texturales pro-ducto de variaciones en las condiciones de los fluidos. Se observa cuarzo con textura en peine y granular de tamaño va-riado señalando condiciones relativamente estables durante su depositación. Las texturas de recristalización en el caso de cuarzo con fantasmas de textura plumosa permiten inferir la existencia previa de calcedonia, que en el caso de la textura esferulítica, se habría formado a partir de la recristalización de geles silíceos intersticiales. La misma se presenta además con textura plumosa y sal y pimienta. La baritina se precipi-ta en forma de lamelas intercrecidas típicas de precipitación en la interfase entre soluciones oxidadas y reducidas. La geo-química de la mineralización indica que está vinculada gené-ticamente con las rocas de caja determinado por la similitud entre la forma de los diagramas de elementos de tierras raras y su contenido mucho menor en la fluorita que en las rocas indica la depositación desde un fluido en las primeras etapas de evolución con poca relación agua / roca. La alcalinidad del medio está determinada por el grado de enriquecimiento de las fluoritas en La y Sr, este último procedente de la alteración de los feldespatos de la roca de caja por los fluidos hidroter-males. La baja cantidad de elementos de tierras raras y la preponderancia de livianas refuerzan su precipitación en un estadio temprano de cristalización. Las fluoritas de Puerto San Antonio tienen anomalías de Eu y Ce cercanas a 1; las de Eu con una distribución diagonal a lo largo de la pendiente +1indi-cando cristalización desde fluidos hidrotermales relativamente oxidantes pero con pequeñas anomalías inherentes al mismo. Las relaciones (La/Yb)N variables y mayores que 1 inducen a pensar que los fluidos mineralizantes eran fluorurados con una concentración de flúor (F) menor a 10-3 M. Los contenidos variables de Sr, Ba, Y, U y (La/Yb)N son similares a los de fluo-ritas asociadas a vetas epitermales de Au-Ag. No se observa una correlación marcada entre el contenido de tierras raras y el color de las fluoritas, vinculándose éste con la heterogenei-dad en la composición de los fluidos. El comportamiento geo-químico de la calcita y la baritina es similar al de la fluorita. Se estudiaron inclusiones fluidas (IF) en fluorita, calcita, baritina y cuarzo, las que se caracterizan por presentar un amplio rango en las temperaturas de homogeneización (Th). En los diferentes estadios, fluorita y cuarzo se depositaron a temperaturas relativamente altas, mientras que la calcita y la baritina lo hicieron a valores más bajos indicando así pulsos de un fluido que se va enfriando paulatinamente. La salinidad de los fluidos es baja a moderada variando las medias entre 2,93 % en peso equivalente a NaCl en calcita, hasta 6,16 % en baritina. La actividad hidrotermal está caracterizada por la presión hidrostática y un nivel somero de emplazamiento, por lo tanto la Th será igual o muy cercana a la temperatura de entrampamiento. Las presiones y por lo tanto las profundidades de depositación de los diferentes minerales, varían ampliamente entre un mínimo de 1,5 bares que corresponden a 17 m por debajo de la tabla de agua y 56 bares que corresponden a 571 metros, indicando diversificación en las presiones por descompresión violenta, descenso de la tabla de agua y enfriamiento del fluido. Los fluidos fueron principalmente acuosos, con baja salinidad, complejos, con cationes de Na+, Ca++, K+, Mg++, Fe++, y gases como SO2, H2S, N2 y CO2 disueltos en muy escasa proporción. El estudio isotópico de los diferentes minerales determinó que la proveniencia del estroncio (Sr) y en consecuencia del calcio en fluoritas de los dos estadios estudiados es diferente. La relación isotópica inicial en el estadio 6 tiene un valor cercano a los de las rocas de la Formación Marifil y en el estadio 2 a los de las metamorfitas prejurásicas de la Formación Nahuel Niyeu. La fuente del carbono (C) en calcita y del azufre (S) en la baritina fue homogénea con una impronta magmática y el origen del oxígeno (O), en calcita y cuarzo de los diferentes estadios, fue versátil con diferentes proporciones de agua meteórica, correspondiendo a mezcla de aguas profundas y superficiales. / Fluorite is a common mineral in Argentina and occurs principally in midwest and northern Patagonia deposits. It is used in steel and chemical industry mainly. This thesis objective is to determine Puerto San Antonio fluorite deposit genesis, northeast of the Northpatagonian Massif, Río Negro Province, Argentina. The mineralization is hosted in a transcurrent fault with 59 azimuth and consists of a main vein and several subparallels. The host rocks are composed of tuffs, tuffaceous sandstones and rhyolitic ignimbrites of the Middle Jurassic age Marifil Complex.The depositation identified by six stages of mineraliza-tion, was marked by abrupt changes in physical, chemical and compositional fluid with brecciation episodes. The ore is fluorite one with calcite, barite, chalcedony and quartz. The breccias are formed by angular and rounded clasts of country rock or earlier stages fluorite surrounded by seve-ral layers of fluorite and chalcedony forming cokcade tex-tures mainly. Highly supersaturated fluids with high flow rate deposited fibrous fluorite, while with a low rate formed colloidal particles precipitating fluorite porce-lain. Unstable precipitation fronts deposited banded fluo-rite with concentration of the elements that produce, at the base of each layer, color anomalies. The same changes are observed in edges and / or crystal centers, as well in the transition from octahedral to cubic habit and crystal growth lines. Rapid variations in temperature and pH of the fluids are determined by the presence of cubic, octahe-dron and dodecahedron granular fluorite habits coexisting. In stage 3, during the boiling initial stage, precipitates lamellar calcite as a result of the rapid loss of CO2 but over the time, the dominating effect is the fall of tempe-rature with respect to loss CO2, where the carbonate is re-placed by adularia and quartz. The presence of SO4 2 + complexes in solution caused precipitation rhombohedral calcite. In the stage 5 calcite an increase in the alkali-nity medium produces the pinacoid elongation. The minerals silica group structures reflect mineralogical and textural changes because of variations in the fluid conditions.Comb and granular texture of varying size quartz is observed with relatively stable condition during deposition. Quartz recrystallization textures with feathery texture phantoms allows to infer chalcedony previous existence, that in the case of spherulitic texture, would have formed from inters-titial silica gels recrystallization. It also comes with feathery and salt and pepper texture. The intergrown lamellae barite is typical of precipitated crystals at the interface between oxidized and reduced solutions. The mine-ralization geochemistry indicates that it is genetically linked with the country rocks by similarity between rare earth elements diagrams shape and their content, lower in fluorite that in rocks indicates deposition from a fluid in early stages of evolution with low water / rock rela-tion. The medium alkalinity is determined by the degree of enrichment fluorite La and Sr, the latter from the altera-tion of country rocks feldspars by hydrothermal fluids.The low amount of rare earth elements and the prevalence of light rare earth elements note its precipitation at an early stage of crystallization. Puerto San Antonio fluori-tes have Eu and Ce anomalies close 1, with Eu diagonal dis-tribution across the slope +1 indicating oxidizing hydro-thermal fluids crystallization with small anomalies. The relations (La / Yb)N variables and greater than 1 suggest that the mineralizing fluids were fluoride with a fluorine (F) concentration less than 10-3. Geochemically the fluo-rites correspond to those associated with epithermal vein Au-Ag. A strong correlation between the content of rare earths elements and the color of fluorite are not shown, the latter is related with the heterogeneity in the fluids composition. The calcite and barite geochemical behavior is similar to fluorite one. Fluid inclusions (FI) were studied in fluorite, calcite, barite and quartz, which are characterized by a wide range in homogenization temperatu-res (Th). In different stages, fluorite and quartz are de-posited at relatively high temperatures, while calcite and barite do to lower values indicating a fluid pulse that cools gradually. The fluids salinity is low to moderate va-rying the average between 2.93% in weight NaCl equivalent in calcite, up to 6.16% in barite. The hydrothermal acti-vity is characterized by hydrostatic pressure and a shallow level of emplacement, therefore Th is equal or clo-se to the entrapment temperature. The pressures and there-fore the deposition depth of different minerals vary wide-ly from a low of 1.5 bars corresponding to 17 m and 56 bars correspond to 571 meters below the water table, indi-cating diversification in pressures by violent decompression, lowering the groundwater level and cooling the fluids. Aqueous fluids with low salinity and complexes with cations Na +, Ca + +, K +, Mg + +, Fe + +, and gases such as SO2, H2S, N2 and CO2 dissolved in very small proportion were observed. The origin of strontium (Sr), and calcium of fluorite in consecuence, by the isotopic study of the different minerals resulted that in the two stages studied is different. The initial isotopic ratio in stage 6 has a close value to the Middle Jurassic Marifil Complex rocks and to the metamorphic Pre Jurassic Niyeu Nahuel Complex in the stage 2. The carbon (C) in calcite and sulfur (S) in barite source was homogeneous with a magmatic imprint while the oxygen (O) in calcite and quartz different stages, was versatile with different proportions of meteoric water, corresponding to deep and shallow waters mixing.
13

Spectral results for perturbed periodic Jacobi operators

Judge, Edmund William January 2017 (has links)
In this text we explore various techniques to embed eigenvalues into the bands of essential spectrum of Hermitian periodic Jacobi operators.
14

The Study of Value Net Analysis of iPhone

Fang, Chih-Ting 05 January 2012 (has links)
Through Value Net Analysis and Co-opetition, we study the reasons why Apple iPhone becomes so successful nowadays. Apple Inc. has changed the ecosystem and the rules of the game, Apple iPhone sells like hot cakes when appearing on the market. Furthermore, the App Store becomes the most popular software shop in recent years. Apple Inc.,a closed ecological system, threatens the telecom companies such as AT&T, and Apple Inc. versus AT&T are complementary with each other. In this case, Apple Inc. wants to use AT&T¡¦s market share to expand its territories; On the other hand, AT&T hopes that the iPhone makes profits to AT&T as well. Therefore, AT&T signs a tie with the Apple iPhone with a 2-year contract, and sells an iPhone to pay for each additional subsidies of USD$ 250-$300 to Apple Inc.. Apple Inc. used the integration of iPod + iTunes software, bringing consumers customized services. Apple Inc. launched an iPhone in 2007 with the concept of iPod + cell phone + Internet, to subvert the traditional cellphone using habits. Apple Inc. would like to fill its product lines, such as, using memory segments (8G, 16G, 32G ...) to distinguish iPhone 4S for high-end markets, iPhone 4 for the middle markets, iPhone 3GS for low-end customers and so forth. Apple Inc. also adopts different pricing, marketing strategies, to bring high added value to its loyal customers. Apple Inc. took a small risk of judo strategy, to turn the incumbent's advantage into obstacles.Apple Inc. was a late mover, only got 10% market share, it still stands on its niche market. Apple Inc. targets on the high-end markets, and differentiates with itself with other players (including NOKIA, MOTOROLA, HTC, SAMSUNG and so on). Apple Inc. changes the scope of game, and redefines the industrial boundaries, so Nintendo and SONY have to face intense competition in few years. Apple Inc. launched App Store, letting different groups of people to join the software application development, in this way Apple Inc. lowers the software price to attract more consumers. Theoritically,that is so-called bilateral market effects (It¡¦s a positive loop between software programmers and consumers). As long as the bilateral market effects get stronger, Apple Inc. will have stronger bargaining power for its suppliers. In order to control the suppliers, Apple Inc. always signs a contract with them or takes part in their shares. Apple Inc. would not only give its suppliers a great amount of single order, but also give same orders in turn between two manufacturers. Under this situation, its suppliers can easily be replaced and Apple Inc. will benefit from this condition. According to reports, Apple Inc. would limit all raw materials of an iPhone and try so hard to cost down in advance, and even follow-up iPhone logistics and maintenance as well. As a result, Apple Inc.¡¦s suppliers do nothing but the OEM jobs for Apple Inc. after all.
15

The Study of Establishment of Brand Position-The Case Study of TransAsia Telecommunications Inc,.

Li, Cheng-Hsiu 20 June 2002 (has links)
The brand-related theories had been valued in recent year. Brand position has been viewed as the core of brand identity, and at the meantime of establishing brands of Taiwan corporations who neglected the importance of brand position. This thesis focused on Taiwan¡¦s mobile service industry and tried to analyze and discuss the ways of establishing brand position of TransAsia Telecommunications Inc. This thesis made the conclusions as followed: (1) Discovering the variable could be differentiated at brand analysis. (2) Choosing and prompting the target-position, which could differentiate itself from other brands¡¦. (3) Communicating the consistent tone of the brand and drawing the attention through being the subject of a talk. (4) The strategic turn of brand position after been merged. Through the discoveries of this thesis, hope it could give some suggestions of building the brand position for practice. Keywords: Brand Position, Brand Identity, TransAsia Telecommunications Inc.
16

The history of Delta Electronics Inc.

Tsai, Shin-ing 24 July 2008 (has links)
A successful business model is worth researching and benchmarking. This qualitative research is about the history of Delta Electronics Inc., which was established 36 years ago. Delta Electronics Inc. has continuously grown and overcome challenges from the macro environment, industry competitors, customers¡¦ preferences via planning and executing strategies, reforming organizational structure, executing performance management, employee development, performing product quality management, improving manufacturing processes, establishing global intranet and internal communication systems, shaping business culture, fulfilling corporate social responsibility needs, etc. This thesis summarizes the key success factors of why Delta has succeeded and was able to unearth the ¡§Delta Way¡¨. This thesis was constructed not only using secondary data, related academic research, and periodicals, but also original primary material such as internal conference records and annual reports which were provided by Delta. Besides, in the summer of 2007, Delta honored me with a two month internship, allowing me experience their business culture, observe daily operations, managerial systems and most importantly of all to interview managers. This study uses the methods mentioned above to try and piece together Delta¡¦s history. The result of this study is as follows. There are five competitive competences that made Delta successful: Firstly, Delta has established a global organizational structure. Secondly, Delta emphasizes constant innovation and R&D. Thirdly, Delta pursues continuous improvement of product quality and manufacturing processes. Fourthly, Delta focuses on the execution and fulfillment of corporate spirit. Lastly, Delta prides itself on social responsibility. In order for the company to immediately serve and satisfy customer demands, Delta sets up sales offices, manufacturing factories and RD centers around the world; especially in regions containing Delta¡¦s critical customer pools. To support Delta¡¦s corporate strategy and become a leading global company, Delta¡¦s organizational structure is that of a matrix configuration which is constructed on three axes and divided on the principles of business function, business unit, and region. To ensure that clear and coherent information can be delivered through a complicated organizational structure, Delta arranges regular corporate conferences to listen to suggestions from different business units and hierarchies. Delta¡¦s success not only comes from its stable system and organizational structures but also from its business mission and vision which drives employees¡¦ commitment and dedication to Delta.
17

Philly-for-profit predicting the success of Edison Schools Inc. in Philadelphia /

Miller, Timothy W. January 2004 (has links) (PDF)
Thesis (B.A.)--Haverford College, Dept. of Economics, 2004. / Includes bibliographical references.
18

A content analysis of Calvin Klein jean advertisements in relationship to consumers' purchase intentions through a qualitative and quantitative approach

Bock, Shana. January 2003 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains v, 37 p. Includes abstract. Includes bibliographical references (p. 32-33).
19

The use of television at Mack Trucks, Inc. a case study /

Tercha, Stephen. January 1988 (has links)
Thesis (M.S.)--Kutztown University of Pennsylvania, 1988. / Source: Masters Abstracts International, Volume: 45-06, page: 2701. Typescript. Abstract precedes thesis as 1 preliminary leaf. Includes bibliographical references (leaves 66-67).
20

How to make QLT a top ten biotechnology company: strategic analysis of growth opportunities /

Collett, A. Nana. Mann, Sacha. January 2005 (has links)
Research Project (M.B.A.) - Simon Fraser University, 2005. / Research Project (Faculty of Business Administration) / Simon Fraser University. MBA-MOT Program. Senior supervisor : Dr. Michael Parent. Also available on the World Wide Web.

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