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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

Marriage and adultery in Tolstoy's Anna Karenina

Slejskova, Nadezda January 1973 (has links)
No description available.
62

Design and thermal analysis for a novel EMCCD camera payload in a 1U CubeSat form factor

Angle, Nicholas Blake 24 June 2024 (has links)
Nüvü Camēras, a Canadian company that designs a range of CCD and EMCCD cameras and controllers, recently began development on a miniaturized EMCCD controller for a CubeSat form factor. The detector for this payload requires near-cryogenic temperatures, approximately 188K, for performance operation. A temperature requirement of that magnitude for a CubeSat form factor is challenging given the low thermal mass, volume, surface area, and power availability for heat storage, dissipation and control systems that would typically be available for larger form factor spacecraft. The goal of this project is to design and per- form thermal analysis for the Nüvü Camēras CubeSat EMCCD Controller that allows for cold-biased active temperature control of both the controller electronics and detector. The EMCCD controller had an operational temperature range of −35◦C to +60◦C while the detector had a performance range of −110◦C to −85◦C with a desire to maintain a resolu- tion of ±0.25◦C. To meet these requirements, a system was designed within 3D modeling software Autodesk Inventor and imported into Thermal Desktop for thermal analysis and iteration. Models were updated based on thermal analysis results, adjusted by hand, and then tested again until a passive cooling and active heating system that met the require- ments was achieved. The final control system was shown to be capable of cooling from 20◦C (293.15K) to −85◦C (188.15K) and beyond given a Sun Synchronous orbit at 600km with attitude control and operational requirements. It was also shown to be capable of heating up, using resistive heaters on key components, beyond the thermal inertia of the system and environment, indicating viable control on orbit. In the future a PID control method can be implemented, and its use is being investigated by Nüvü Camēras for achieving the desired resolution of ±0.25◦C in the future. / Master of Science / Nüvü Camēras, a Canadian company that designs a range of Charge-Coupled Device (CCD) and Electon Multiplication Charge-Coupled Device (EMCCD) cameras and controllers, re- cently began development on a miniaturized EMCCD controller for a CubeSat form factor. CubeSats are a standard for nanosatellites, a classification of spacecraft with dimensions on the order of centimeters instead of meters. The Nüvü Camēras CubeSat EMCCD controller will operate a detector that enables the collection of extremely low light images, or even the counting of individual photons, that other CCD detectors are not capable of in such a form factor. This kind of quality comes with operating requirements such as a very low tempera- ture for the detector, which can be challenging to achieve in a CubeSat. The challenges are the low thermal mass for heat storage, low volume and surface area for fitting components and dissipating heat via radiation, and low power availability to run active systems such as cryocoolers. The goal of this project was to develop a temperature management system that tackles these challenges and allows the operation of the Nüvü Camēras CubeSat EMCCD controller on a variety of Low Earth Orbit (LEO) missions. To achieve this, a passive cool- ing system was designed to be cooled below the necessary temperature such that it can be effectively warmed back up as a method of active control with resistive heaters. This system was designed in a Computer Aided Design (CAD) program called Autodesk Inventor and analyzed in a thermal analysis program called Thermal Desktop. After a final analysis of the full setup, it was determined that the system would allow for thermal management at LEO for the Nüvü Camēras CubeSat EMCCD controller and detector.
63

ELTA ir BNS naujienų agentūrų veikla. LEO LT atvejis / The activity of News Agencies ELTA and BNS. The case of LEO

Kozlovskytė, Inga 08 September 2009 (has links)
Tada, kai dar nebuvo žiniasklaidos priemonių, naujienos sklido iš lūpų į lūpas. Ir tik per pastaruosius amžius naujienų komunikacijos vaidmuo išaugo labai stipriai, konstruodamas mūsų požiūrį į tai kas vyksta aplinkui. Tuo tarpu naujienų agentūros užima labai svarbias pozicijas socialinės tikrovės konstravime, nes tai vieta, kur gimsta žinios, ir tik po to apipinamos į reikiamą kontekstą bei išleidžiamos. Šiandien naujienų agentūroms priskiriamos be galo svarbios funkcijos: dalyvauti tikrovės konstravime, viešinti aktualius įvykius ir būti svarbia priemone skleidžiant moralines visuomenės vertybės. Šiame darbe yra analizuojama, kaip naujienų agentūros BNS ir ELTA pateikia žinias apie vieną kontraversiškiausių Lietuvos įvykių – LEO LT projekto susikūrimą. Darbo tikslas – palyginti BNS ir ELTOS pranešimų apie LEO LT turinį ir nustatyti, ar žinučių tekstuose yra subjektyvumo apraiškų, išryškėjančių iš vertinamųjų elementų, informacijos atrankos, pateikimo būdų ir kt. Interviu metu su agentūrų vadovais bandoma išsiaiškinti, kokie yra žinių atrinkimo ir pateikimo kriterijai, žinių kūrimo tendencijos, agentūrų veikimo principai, kiek ir kokius įvykius, susijusius su LEO LT atveju pateikia viena agentūra, o kiek kita. Šio mokslinio darbo objektas yra BNS ir ELTOS pranešimai žiniasklaidai apie LEO LT atvejį bei minėtų agentūrų žinutėse pateikiama informacija, jos tikslumas, naujienų pateikimo būdai. Pirmasis darbo uždavinys, – paaiškinti, kokią raišką įgyja žinučių ideologija... [toliau žr. visą tekstą] / The title of the thesis – The activity of News Agencies ELTA and BNS. The case of LEO. When there were no tools of mass communication, the news were spreading from lip to lip. During last centuries the act of news communication rapidly grew up, building up our attitude towards everything that is going around us. Meanwhile, the news agencies take very important positions in building up social reality, because it is the place where news born, and after that they are being put into the context that is needed and released. Today news agencies have very important functions: to take a part in building up reality, to publicize topical events and to be the important tool in spreading the moral values of the society. The main thing analysed in this project is how the news agencies BNS and ELTA give news about one of the most controversial events in Lithuania – the creation of project of LEO LT. The purpose of this project is to compare the content of BNS and ELTA reports about LEO LT and to estimate if there are any subjectivity in text messages, which shows up from the appreciable elements, choosing information, ways of presentation and etc. During the interview with the heads of the news agencies, it is being tried to ascertain, what are the criterions of sorting out and giving the news, tendencies of creating news, principles of news agencies working, how many and what events, having a connection with the case of LEO LT, gives two agencies. The objects of this... [to full text]
64

A Critical Analysis of the Works of Leo Sowerby

Parks, O. G. 08 1900 (has links)
Leo Sowerby is an American composer who has, in the writer's opinion, made a fine contribution to the field of modern music. This fact will be substantiated in the following study, the purpose of which will be to examine and to analyze to some extent the works of this eminent Chicago composer, teacher, organist, and choir-master. This study will-be of particular interest to students of the organ, for it concerns itself chiefly with the organ works of Sowerby, and to students of composition and modern harmonic trends, for the study high lights the composer's characteristic procedures in these two directions.
65

Theologie in der Kirche : eine Untersuchung der methodologischen Grundlagen der Theologie und des Verständnisses der Katholizität der Kirche bei Avery Kardinal Dulles und bei Leo Kardinal Scheffczyk /

Lutz, Christian, January 2010 (has links)
Thesis (doctoral)--Pontificia Universita Gregoriana, Roma, 2009. / Includes bibliographical references (p. 323-340).
66

Le dualisme religieux chez Leo Tolstoy /

Beauchamp, Marie-Claude. January 1984 (has links)
No description available.
67

The reign of Leo VI (886-912) : personal relationships and political ideologies

Tougher, Shaun F. January 1994 (has links)
Leo VI (886-912) is an emperor who has suffered from a hostile and inadequate press. He has been portrayed as a weak and careless emperor, known mainly for his dubious parentage and marital exploits. This thesis questions these popular perceptions of Leo, and attempts to present a more realistic account of the emperor and the politics of his age. The aspects of the reign tackled focus on essential elements of Leo's life and rule, presented in a rough chronological framework, and the themes of personal relationships and political ideologies are recurrent. Chapter One examines Leo's relationship with Basil I and his attitude to his Macedonian heritage. Chapter Two considers the fate of the monumental figure of Photios at the emperor's hands. Chapter Three deals with the position and role of the 'all powerful' Stylianos Zaoutzes during the first half of the reign. Chapter Four ponders the origin and meaning of Leo's 'wise' epithet. Chapter Five focuses on the emperor's four marriages. Chapter Six turns to the course of foreign affairs during the reign, concentrating on Bulgaria and the Arab navy, and considers the emperor's attitude towards these military problems. Chapter Seven examines the emperor's relationship with his senatorial officials, focusing on two distinct groups, eunuchs and the generals who originated from families of the eastern frontier. Finally Chapter Eight addresses the tense relationship that existed between Leo and his brother and co-emperor Alexander. What emerges from a consideration of these aspects of Leo and his reign is that this is an emperor who does not deserve the popular perceptions that still persist about him. He was an emperor who forged a 'new' and distinctive imperial style, a style that should not deceive us; he may have been literate, sedentary and city-based, but he was also forceful, strong-willed and conscientious.
68

Desenvolvimento de novos biolubrificantes hidr?ulicos derivados dos ?leos de maracuj? e de moringa in natura e epoxidados / Development of new hydraulic biolubricants derived from passion fruit and moringa oils in natura and epoxidized

Silva, Maria Susana 02 February 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-02-04T23:03:25Z No. of bitstreams: 1 MariaSusanaSilva_TESE.pdf: 6744977 bytes, checksum: 2a8c2506ef32d61f3992dba778ac3ec1 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-02-04T23:08:50Z (GMT) No. of bitstreams: 1 MariaSusanaSilva_TESE.pdf: 6744977 bytes, checksum: 2a8c2506ef32d61f3992dba778ac3ec1 (MD5) / Made available in DSpace on 2016-02-04T23:08:50Z (GMT). No. of bitstreams: 1 MariaSusanaSilva_TESE.pdf: 6744977 bytes, checksum: 2a8c2506ef32d61f3992dba778ac3ec1 (MD5) Previous issue date: 2015-02-02 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / O aumento da consci?ncia ambiental, maximizando a biodegradabilidade e minimizando a ecotoxicidade, ? a for?a motriz principal para os novos desenvolvimentos tecnol?gicos. Deste modo, os lubrificantes biodegrad?veis utilizados em ?reas ambientalmente sens?veis podem ser mais explorados. O objetivo desse trabalho foi obter novos biolubrificantes a base de ?leo de maracuj? (Passiflora edulis Sims f. flavicarpa Degener) e de moringa (Moringa oleifera Lamarck), in natura e epoxidados e otimizar o uso de um novo pacote de aditivos atraves da metodologia de planejamento experimental para sua utiliza??o como fluido hidr?ulico. Na primeira etapa do trabalho foi realizada a otimiza??o do processo de epoxida??o dos ?leos utilizando o planejamento experimental fracionado 24-1 , variando a temperatura, tempo de rea??o, raz?o molar de ?cido f?rmico e a raz?o molar de per?xido de hidrog?nio. Em seguida, foi investigada a seletividade, termodin?mica e a cin?tica da obten??o dos dois ep?xidos a 30, 50 e 70 ?C. Os resultados dessa primeira etapa confirmaram que para a epoxida??o do ?leo de maracuj? s?o necess?rias 3 horas de rea??o, 30 ?C e uma raz?o H2O2/C=C/HCOOH (1:1:1) e para o ?leo de moringa foram necess?rias 3 horas de rea??o, 30 ?C e uma raz?o de H2O2/C=C/HCOOH (1:1:1,5). Os resultados das convers?es finais foram iguais a 83,09% (?0,3) para o ep?xido de ?leo de maracuj? e 91,02% (?0,4) para o ep?xido do ?leo de moringa. Em seguida, foi feito o planejamento experimental fatorial 23 para avaliar quais as melhores concentra??es do inibidor de corros?o e antidesgaste (IC), antioxidante (BHA) e extrema press?o (EP). Os biolubrificantes obtidos nessa etapa foram caracterizados segundo as normas DIN 51524 (Part 2 HLP) e DIN 51517 (Part 3 CLP). O processo de epoxida??o dos ?leos foi capaz de melhorar a estabilidade oxidativa e diminuir o ?ndice de acidez total quando comparados aos ?leos in natura. Em termos de desempenho f?sico-qu?mico como lubrificantes, o melhor fluido foi o ep?xido do ?leo de moringa aditivado (EMO-ADI), seguido do ep?xido do ?leo maracuj? aditivado (EMA-ADI) e, por ?ltimo, o ?leo de maracuj? in natura sem aditivos (OMA). Para finalizar, foi feita a investiga??o de seus comportamentos tribol?gicos sob condi??es de lubrifica??o lim?trofe. O desempenho tribol?gico dos lubrificantes desenvolvidos foi analisado em um equipamento HFRR (High Frequency Reciprocating Rig) e atrav?s da medi??o do coeficiente de atrito, que ocorre durante o contato e a forma??o do filme lubrificante, durante o ensaio. O desgaste foi avaliado atrav?s de microscopia ?ptica e microscopia eletr?nica de varredura (MEV). Observou-se que, em todos os ensaios, foi formado um filme lubrificante e que a adi??o de EP e IC nas bases vegetais de ?leo de maracuj? e moringa in natura n?o ocasionou uma redu??o significativa no desgaste. Os biolubrificantes desenvolvidos a partir de ?leo de maracuj? e moringa modificados via epoxida??o apresentaram propriedades tribol?gicas superiores aos fluidos comerciais testados, mostrando serem potenciais lubrificantes para substitui??o dos fluidos comerciais de base mineral. / With the increasing environmental awareness, maximizing biodegradability and minimizing ecotoxicity is the main driving force for new technological developments. Thus, can be developed new biodegradable lubricants for use in environmentally sensitive areas. The aim of this study was to obtain new bio-lubricants from passion fruit (Passiflora edulis Sims f. flavicarpa Degener) and moringa (Moringa oleifera Lamarck) epoxidized oils and develop a new additive package using experimental design for their use as a hydraulic fluid. In the first stage of this work was performed the optimization of the epoxidation process of the oils using fractional experimental design 24-1 , varying the temperature, reaction time, ratio of formic acid and hydrogen peroxide. In the second step was investigated the selectivity, thermodynamics and kinetics of the reaction for obtaining the two epoxides at 30, 50 and 70 ?C. The result of the experimental design confirmed that the epoxidation of passion fruit oil requires 2 hours of reaction, 50 ?C and a ratio H2O2/C=C/HCOOH (1:1:1). For moringa oil were required 2 hours reaction, 50 ?C and a ratio of H2O2/C=C/HCOOH (1:1:1.5). The results of the final conversions were equal to 83.09% (? 0.3) for passion fruit oil epoxide and 91.02 (?0,4) for moringa oil epoxide. Following was made the 23 factorial design to evaluate which are the best concentrations of corrosion inhibitor and anti-wear (IC), antioxidant (BHA) and extreme pressure (EP) additives. The bio-lubricants obtained in this step were characterized according to DIN 51524 (Part 2 HLP) and DIN 51517 (Part 3 CLP) standards. The epoxidation process of the oils was able to improve the oxidative stability and reduce the total acid number, when compared to the in natura oils. Moreover, the epoxidized oils best solubilized additives, resulting in increased performance as a lubricant. In terms of physicochemical performance, the best lubricant fluid was the epoxidized moringa oil with additives (EMO-ADI), followed by the epoxidized passion fruit oil with additives (EPF-ADI) and, finally, the passion fruit in natura oil without additives (PFO). Lastly, was made the investigation of the tribological behavior under conditions of boundary lubrication for these lubricants. The tribological performance of the developed lubricants was analyzed on a HFRR equipment (High Frequency Reciprocating Rig) and the coefficient of friction, which occurs during the contact and the formation of the lubricating film, was measured. The wear was evaluated through optical microscopy and scanning electron microscopy (SEM). The results showed that the addition of extreme pressure (EP) and anti-wear and corrosion inhibitor (CI) additives significantly improve the tribological properties of the fluids. In all assays, was formed a lubricating film that is responsible for reducing the coefficient of metal-to-metal wear. It was observed that the addition of EP and IC additives in the in natura vegetable oils of passion fruit and moringa did not favor a significant reduction in wear. The bio-lubricants developed from passion fruit and moringa oils modified via epoxidation presented satisfactory tribological properties and shown to be potential lubricants for replacement of commercial mineral-based fluids.
69

Obten??o de sistemas macroemulsionados a partir de ?leos vegetais, para incorporar extrato seco de punica granatum

Abrantes, Antonio C?sar Nobre de 30 June 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-03T18:22:01Z No. of bitstreams: 1 AntonioCesarNobreDeAbrantes_DISSERT.pdf: 2550671 bytes, checksum: cb02cd1401011998407d1b88ed485674 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-04T20:35:17Z (GMT) No. of bitstreams: 1 AntonioCesarNobreDeAbrantes_DISSERT.pdf: 2550671 bytes, checksum: cb02cd1401011998407d1b88ed485674 (MD5) / Made available in DSpace on 2017-01-04T20:35:17Z (GMT). No. of bitstreams: 1 AntonioCesarNobreDeAbrantes_DISSERT.pdf: 2550671 bytes, checksum: cb02cd1401011998407d1b88ed485674 (MD5) Previous issue date: 2016-06-30 / As emuls?es s?o formula??es empregadas em diferentes segmentos da ind?stria, principalmente na ?rea aliment?cia, terap?uticas, cosm?ticas. Os ?leos de Linum usitatissimum e Sesamun indicum apresentam propriedades anti-inflamat?rias, em raz?o da presen?a de ?cidos graxos essenciais, podendo ter aplica??o na prepara??o de medicamentos pelo potencial farmacol?gico. O objetivo desse trabalho foi usar as propriedades farmacol?gicas do Punica granatum, como ativo, em sistema emulsionado, para aplica??o fitoter?pica. As emuls?es foram obtidas a partir de diagrama tern?rio utilizando a ?gua destilada como fase aquosa e a lecitina de Glycine max como tensoativo. Na prepara??o dos dois diagramas, na fase oleosa, utilizou-se os ?leos de Linum usitatissimum e Sesamun indicum. Nos diagramas obtidos, na regi?o de emuls?o do tipo O/A, foram escolhidos seis sistemas (tr?s em cada diagrama) por apresentar maior estabilidade. Os conservantes adicionados aos sistemas foram metilparabeno (Nipargin) e propilparabeno (Nipazol) e o estabilizador de emuls?es, hidrocol?ide Xanthan Gum (goma xantana). Da casca do vegetal Punica granatum foi obtido extrato aquoso, e em seguida liofilizado. Foram definidos tr?s percentuais (0,3%, 0,5% e 1,0%) de extrato liofilizado em cada sistema. Essas formula??es foram caracterizadas atrav?s das t?cnicas de medida pH, viscosidade, condutividade, estabilidade acelerada e estabilidade t?rmica. Antes de adicionar o bioativo foi empregada a espectrofotometria no Ultravioleta para quantificar o bioativo presente no p? da casca da rom?. A formula??es com a adi??o do extrato tiveram seus valores de pH diminu?dos e viscosidade aumentada quanto maior foi o percentual do extrato no meio. Isso se deve por que o extrato apresenta fen?is de car?ter ?cido e a quantidade maior de extrato no meio precisa de mais mol?culas para hidratar esse extrato, tornando o meio com menos ?gua livre. / Emulsions are formulations used in different industry segments, mainly in the food, pharmaceutical, cosmetic industry. The Linum usitatissimum and Sesamun indicum oils have anti-inflammatory properties, due to the presence of essential fatty acids and they can be applied in the preparation of drugs for the pharmacological potential. The aim of this study was to use the dried extract of Punica granatum to incorporate in the macro emulsified system, as active one, for herbal application. The emulsions were obtained from ternary diagram using distilled water as aqueous phase and Glycine max lecithin as surfactant. In preparing the two diagrams in the oil phase, the Linum usitatissimum and Sesamun indicum oils were used. In the diagrams obtained in the region of emulsion type O / A, they were selected six systems (three in the diagram) due to presenting greater stability. Preservatives added to systems were methylparaben (Nipagin?) and propylparaben (Nipazol?) and stabilizer of emulsions, hydrocolloid xanthan gum (xanthan gum). From peel Punica granatum plant, was obtained the aqueous extract, and then lyophilized. They have been defined three percentage (0.3%, 0.5% and 1.0%) of lyophilized extract in each system. These formulations were characterized by measuring pH techniques, viscosity, conductivity, accelerated stability and thermal stability. Before adding the bioactive was used the spectrophotometry in the ultravioleta and infrared to quantify the bioactive present in the pomegranate peel powder, and was also applied to the optical microscopy technique to determine the droplet size. The formulations with the addition of the dry extract of Punica granatum had their pH values decreased and viscosity increased as higher was the percentage of the extract in the medium. This happens because the extract has phenols of acid character and the largest amount of extract in the middle needs more molecules to hydrate this formulation, making the middle less free water.
70

El Quijote de Coseriu

Wiesse Rebagliati, Jorge Raúl 12 April 2018 (has links)
En su amplia obra lingüística, Eugenio Coseriu (Mihaileni, 1921 - Tübingen, 2002), acude varias veces a la literatura para ejemplificar  conceptos lingüísticos teóricos e incluso para modelarlos. Como ocurre con varios estudiosos del siglo XX (José Ortega y Gasset o Mijaíl Bajtín, por ejemplo), el Quijote es, para Coseriu, incitación para formular reflexiones que no se aplican exclusivamente a él, como sí lo hacen otras obras relevantes del cervantismo del siglo XX, señaladamente los trabajos de Stephen Gilman y Edward C. Riley. El presente artículo busca rastrear las referencias al Quijote y a Cervantes en la obra de Coseriu y, sobre todo, presentar y discutir la corrección hecha por Coseriu al importante trabajo de Leo Spitzer “Perspectivismo lingüístico en el Quijote”. / In his extensive linguistic work, Eugenio Coseriu (Mihaileni, 1921 - Tübingen, 2002), uses literature several times to exemplify theoretical linguistic concepts and even to model them. As is the case with several 20th century scholars (José Ortega y Gasset or Mijaíl Bajtín), Don Quixote is, for Coseriu, a touchstone to formulate reflections that do not apply exclusively to it, as other relevant works of 20th century’s Cervantism, such as Stephen Gilman’s or and Edward C. Riley’s, do. This article seeks to trace the references of Don Quixote and Cervantes in Coseriu’s work and, above all, to present and discuss the correction made by Coseriu to Leo Spitzer’s “Perspectivismo lingüístico en el Quijote”.

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