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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.
241

O funcionamento ideológico na produção da hipercorreção / The ideological functioning in the production of hypercorrection

Azambuja, Elizete Beatriz, 1962- 21 August 2018 (has links)
Orientador: Eni de Lourdes Puccinelli Orlandi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Estudos da Linguagem / Made available in DSpace on 2018-08-21T19:00:36Z (GMT). No. of bitstreams: 1 Azambuja_ElizeteBeatriz_D.pdf: 5918005 bytes, checksum: 160726167ee1a9371afda7949e4ea570 (MD5) Previous issue date: 2012 / Résumé: Avec ce travail, nous cherchons de comprendre la production de "la hypercorrection". Nous traitons cette notion, qui est traditionnellement étudiée par la sociolinguistique, du point de vue de l'analyse de discours. C'est à cause de cette différence de perspective théorique que nous utilisons des guillemets pour leterme. Compte tenu que la langue et le sujet ne sont pas séparés, nous travaillonsavec le discours sur la langue et la façon dont l'idéologie se matérialise dans La discursivité dominante dans notre société. De cette manière, nous faisons une lecture de certains aspects qui, historiquement, constituent les idées linguistiques. Le corpus que nous organisons est hétérogène en ce qui concerne les conditions de production. Nous le divisons en deux ensembles d' énoncés. Le premier ensemble comprend des énoncés dans lesquels nous analisons le discours sur la langue produit par des sujets dans diverses positions sociales. L'autre groupe d'énoncés nous permet d'observer le fonctionnement des différents faits de "la hypercorrection". Notre proposition de reflection sur ces faits linguistico-discursifs du point de vue discursif nous permet de les penser non pas comme des <<erreurs>>, mais comme équivoque, point où la langue, sujette à la faille, s'inscrit dans l'histoire. En outre, nous considérons ces faits comme des marques Du fonctionnement de l'idéologie, comme un indice d'affectation du sujet par la langue institutionnalisée, affrontement dans lequel la mémoire qui se réfère au discours de l'écriture devient visible. Cette étude nous permet de mettre en rapport la production de "la hypercorrection" et la tension entre la langue imaginaire et le fonctionnement de la langue fluide, le décallage entre la langue nationale et langue maternelle. En outre, cette étude nous aide à comprendre que "la hypercorrection" se construit idéologiquement entre l'inquiétude du sujet face à sa langue maternelle et/ou leur désir de s'inscrire dans une langue considérée comme légitime / Resumo: Com este trabalho, buscamos compreender a produção da "hipercorreção". Tomamos essa noção, tradicionalmente estudada pela Sociolinguística, para tratála pela perspectiva da Análise de Discurso e essa diferença de olhar demarcamos pelo uso das aspas no termo. Considerando que não se separam língua e sujeito, lidamos com o discurso sobre a língua e o modo com que a ideologia se materializa na discursividade que predomina em nossa sociedade, fazendo uma leitura de alguns aspectos que, historicamente, constituem as ideias linguísticas. O corpus que organizamos é heterogêneo em relação às condições de produção e o subdividimos em dois conjuntos de enunciados, sendo que o primeiro é constituído por enunciados em que analisamos o discurso sobre a língua produzido por sujeitos em posições sociais diversificadas. O outro grupo de enunciados possibilita-nos observar o funcionamento de diferentes fatos de "hipercorreção". A nossa proposta de reflexão destes fatos linguístico-discursivos da perspectiva discursiva permite-nos pensá-los não como "erro", mas como equívoco, ponto em que a língua, sujeita à falha, se inscreve na história. Além disso, consideramos tais fatos como marcas do funcionamento da ideologia, enquanto indício do afetamento do sujeito pela língua institucionalizada, embate em que a memória que remete ao discurso da escrita se torna visível. Este estudo nos possibilita relacionar a produção da "hipercorreção" com a tensão entre a língua imaginária e o funcionamento da língua fluida, com o descompasso entre a língua nacional e a língua materna. Além disso, contribuiu para que compreendêssemos que ela se constitui ideologicamente entre o desassossego do sujeito com a sua língua materna e/ou o seu desejo de se inscrever na língua que é considerada legítima / Abstract: With this work, we seek to understand the production of "hypercorrection." We take this notion, traditionally studied by Sociolinguistics, to treat it from the perspective of discourse analysis and the difference in look we established for the use of the term in quotation marks. Whereas not separate language and subject, dealing with the discourse about language and the way that ideology is embodied in the discourse that prevails in our society, doing a reading of some aspects that historically constitute the linguistic ideas. The corpus that we organize is heterogeneous in relations to the conditions of production and we subdivided into two sets of statements, being the first of which consists of statements in which we analyze the discourse on language produced by subjects in diverse social positions. The other group of statements enables us to observe the functioning of different facts "hypercorrection." Our proposal for consideration of these facts the linguistic-discursive discursive perspective allows us to think of them not as "error", but as equivocal, at which point the language, subject to failure, is written falls in the history. Furthermore, we consider such facts as trademarks operation of ideology, as evidence of the subject's tongue being affects of the institutionalized language, in which memory which refers to speech writing becomes visible. This study enables us to relate the production of "hypercorrection" with the tension between the imaginary language and the function of the fluid language, with the mismatch between national language and mother tongue. Furthermore, it contributed to for us to understand that it is constitute ideologically between the subject's restlessness with their mother tongue and/or their desire to enroll in the language that is considered legitimate / Doutorado / Linguistica / Doutora em Linguística
242

Kitkaväsyminen akselien kutistusliitoksissa

Juuma, T. (Teuvo) 01 October 2001 (has links)
Abstract Fretting is present where the contacting surfaces of mechanical parts are subjected to rubbing and an alternating stress, resulting in fatigue in the material. This is the situation between the hub and shaft in a shrink-fitted assembly. In practice, fretting is found in the same assembly with normal fatigue, and it occurs in the axle in a shrink-fit between an axle and a hub, while normal fatigue cracks are found outside the assembly. Fretting phenomena have been investigated by many authors in laboratories, but the dimensioning criteria for shrink-fit assemblies are insufficient for the construction engineer. Fretting causes a considerable reduction in the fatigue strength of a shrink-fit assembly, and failures caused by fretting are as numerous as failures resulting from normal fatigue. The purpose of this investigation was to examine the effect of hub material, contact pressure, slip amplitude and shaft geometry on fatigue strength. The goal of this investigation was to determine an optimal contact pressure and a favourable fillet radius and axle diameter ratio at which fretting failure can be avoided and maximum normal fatigue strength will be obtained. The torsional fatigue strength of shrink-fitted shaft couplings was estimated using tests that varied the material of the hub, the contact pressure, the geometry of the shaft and the torsional stress amplitude of the shrink-fitted assembly. Based on the information obtained from the test, aluminium as a hub material appears to produce little damage to a steel shaft, whereas bronze appears to cause damage and fatigue. Cast iron and steel caused a medium amount of damage. To increase contact pressure at the shoulder, hub overhang past the shoulder was used. These experiments showed that increasing the contact pressure decreased the slip amplitude, thereby reducing fretting. With low contact pressure, shaft fracturing began from fretting fatigue inside the hub, but with high contact pressure the shaft fractured at the fillet due to normal fatigue. Selecting the fillet radius according to the contact pressure makes it possible to dimension the shrink-fit shaft assembly to prevent fretting. The shrink-fitted shaft should be designed according to the normal fatigue limit, because fretting fatigue may occur when the number of load cycles exceeds 2×107. Fretting can be prevented by using a sufficiently high contact pressure and by choosing optimal ratios for the fillet radius and the diameter. To avoid fretting, the slip amplitude should be under 3 μm. This is achieved by using a contact pressure of over 100 N/mm2, calculated according to Lamé's theory. A method for dimensioning a shrink-fitted shaft with respect to fretting fatigue was presented based on a specific geometry (Ø 50 mm) and the materials used in the tests. The method was applied in verifying the fretting fatigue of a shrink-fitted shaft with a diameter of 300 mm. / Tiivistelmä Kitkaväsyminen esiintyy yleisesti, kun koneenosien kontaktipintoihin kohdistuu edestakainen jännitysamplitudi hankaavan liikkeen lisäksi johtaen materiaalin väsymiseen. Tällainen tilanne vallitsee navan ja akselin välissä kutistusliitoksessa. Kitkaväsyminen esiintyy käytännössä samassa kutistusliitoksessa kuin normaali väsyminenkin ja se ilmenee navan ja akselin välissä yleensä akselissa, kun taas tavanomainen väsyminen tapahtuu akselissa liitoksen ulkopuolella. Kitkaväsymistä on tutkittu paljonkin, mutta kutistusliitoksen mitoituskriteerit kitkaväsymisen osalta ovat puutteelliset. Kitkaväsyminen aiheuttaa merkittävän väsymislujuuden heikkenemisen sekä täten väsymisiän alenemisen kutistusliitoksessa ja sen aiheuttamat vauriot ovat määrältään samaa luokkaa tavanomaisen väsymisen kanssa. Tämän tutkimuksen tarkoituksena oli selvittää napamateriaalin, liitospaineen, liukuma-amplitudin ja geometrian vaikutus väsymislujuuteen. Tavoitteena oli määrittää optimaalinen liitospaine sekä sopivat olakkeen pyöristyssäde ja akselisuhde, jotta kitkaväsyminen voidaan välttää ja saavuttaa maksimaalinen normaali väsymislujuus. Kitkaväsymislujuutta väännön suhteen testattiin varioimalla napamateriaalia, liitospainetta, geometriaa ja jännitysamplitudia. Testien perusteella alumiininen napamateriaali sopi hyvin teräsakselin kanssa, kun taas pronssi aiheutti akseliin pintavaurion ja sitä kautta väsymisilmiön. Teräs- ja valurautanapa olivat näiden kahden materiaalin välissä. Liitospaineen nostamiseksi olakkeen reunalla käytettiin navan ylitystä olakkeen yli. Kokeet osoittivat kitkaväsymisen vähenevän korkeammilla liitospaineilla liukuman aletessa. Alhaisella liitospaineella akselin vaurioituminen alkoi kitkaväsymisenä navan sisältä, mutta hyvin korkealla liitospaineella murtuminen tapahtui olakkeesta tavanomaisena väsymisenä. Valitsemalla pyöristyssäde liitospaineen perusteella kutistusliitos on mitoitettavissa kitkaväsymistä vastaan. Kutistusliitos tulisi mitoittaa tavanomaisen väsymisen mukaan, koska kitkaväsymismurtuma voi tapahtua kuormanvaihtoluvulla yli 2×07. Kitkaväsyminen on ehkäistävissä käyttämällä riittävän korkeata liitospainetta sekä sopivaa olakkeen pyöristyssädettä yhdistyneenä oikeaan akselisuhteeseen. Kitkaväsyminen estyy kun liukuma-amplitudi on alle 3 μm. Tämä on saavutettavissa liitospaineella yli 100 N/mm2 laskettuna Lamén teorian mukaan. Tutkimuksessa on esitetty mitoitusmenetelmä kitkaväsymisen suhteen perustuen Ø 50 mm akselilla sekä käytetyillä materiaaleilla tehtyihin testeihin. Menetelmää on sovellettu kitkaväsymisen tarkasteluun kutistusliitokseen, jonka akselin halkaisija on 300 mm.
243

Avaliação do fenômeno de Stick-Slip em materiais de fricção com utilização de um tribômetro

Franceschini, Joel January 2014 (has links)
Nos sistemas de freio automotivo, o principal componente que determina seu desempenho é o material de fricção, pois um bom material de fricção deve garantir estabilidade no atrito em diferentes condições de uso, além de possuir resistência à corrosão, longa vida útil, baixa taxa de desgaste, boa relação custo versus desempenho e baixo ruído. Desde que o conforto dos veículos tornou-se um fator importante para indicar sua qualidade, eliminar ou reduzir os ruídos e vibrações de seus componentes passou a ser uma vantagem competitiva no mercado automotivo, e, o problema de ruído nos sistemas de freios vem sendo um dos maiores causadores de reclamações de clientes nos últimos anos. O ruído de freio é na maioria das vezes o resultado de uma vibração auto excitada induzida pela fricção ou uma instabilidade dinâmica do sistema de freio. O processo de stick-slip é um típico exemplo de oscilação induzida por atrito, observada em baixas velocidades de deslizamento e geralmente resulta em vibrações, que geram ruídos graves e rangidos. Com o objetivo de verificar a viabilidade da utilização das medições de vibração durante a ocorrência do fenômeno do stick-slip para a caracterização de materiais de fricção utilizando um tribômetro, foram preparados seis materiais de fricção produzidos pela empresa Fras-le, fabricante de materiais de fricção para freios automotivos. Os ensaios foram realizados no Laboratório de Tribologia (Latrib) da Escola de Engenharia da Universidade Federal do Rio Grande do Sul (UFRGS). No tribômetro utilizado nos ensaios foi instalado um acelerômetro sobre o suporte onde é fixada a pastilha do material de fricção a ser ensaiado. Vários ensaios foram realizados, cada um sob ação de força normal e velocidade de giro do disco constantes. Os resultados dos ensaios demonstraram que o tribômetro apresenta excelente desempenho para caracterização de materiais de fricção, possibilitando o desenvolvimento de novos materiais a partir de ensaios realizados neste equipamento. A avaliação da resposta da aceleração da vibração obtida nos ensaios demonstrou que a resposta da vibração é dependente dos diversos parâmetros medidos, como deslocamento, velocidade e variação de torque, e para melhor prever a propensão de um determinado material em apresentar vibração de stick-slip deve-se levar em consideração, além da variação de torque, o torque máximo de cada ciclo de stick-slip. Além disso, o uso do acelerômetro para avaliação de ensaios de stick-slip mostrou-se viável e seu uso deve ser estimulado em trabalhos futuros. / In automotive brake systems, the main component that determines their performance is the friction material, because good friction material must ensure stability in friction under different conditions of use, as well as corrosion resistance, long life, low wear rate, good relation between cost and performance, and low noise. Since the comfort of vehicles has become important factor to indicate its quality, eliminate or reduce the noise and vibration of its components has become a competitive advantage in the automotive market, and the problem of noise in brake systems has been a cause of customer complaints in recent years. The brake noise is most often the result of a self-excited vibration induced friction or dynamic instability of the brake system. The stick-slip phenomenon is a typical example of oscillation induced by friction observed at low sliding speeds and generally results in vibrations which generate noise. In order to check the feasibility of using vibration measurements during the occurrence of the stick-slip phenomenon in the characterization of friction materials using a tribometer, were prepared six friction materials produced by the company Fras-le, manufacturer of friction materials for automotive brake. The tests were performed in the Laboratory of Tribology (Latrib) of the School of Engineering at Federal University of Rio Grande do Sul (UFRGS). In tribometer used for testing an accelerometer was installed on the support of the pad of friction material to be tested. Several tests were conducted, each under constant normal force and speed of rotation of the disk. The test results showed that the tribometer shows excellent performance for characterization of friction materials, enabling the development of new materials from tests performed on this equipment. The evaluation of the response of vibration acceleration obtained in the tests demonstrated that the response of vibration is dependent on various measured parameters, such as displacement, velocity and torque variation, and to better predict the propensity of a material to present vibration stickslip must take into account both the variation of torque and the maximum torque of each cycle of stick-slip. Furthermore, the use of accelerometer for assessing stick-slip tests was viable and its use should be encouraged in future work.
244

Singular behavior near surfaces: boundary conditions on fluids and surface critical phenomena / 表面近くでの特異な振る舞い:流体の境界条件と表面臨界現象

Nakano, Hiroyoshi 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第21551号 / 理博第4458号 / 新制||理||1640(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 佐々 真一, 准教授 藤 定義, 准教授 荒木 武昭 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
245

Active Tectonics of the Northeastern Tibetan Plateau / チベット高原北東部のアクティブテクトニクス

Chen, Peng 25 November 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第22113号 / 理博第4540号 / 新制||理||1652(附属図書館) / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)教授 福田 洋一, 教授 岩田 知孝, 准教授 深畑 幸俊 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
246

STUDIES ON NONLINEAR VISCOELASTIC BEHAVIOR OF HIGHLY ENTANGLED POLYMER SYSTEMS / 高度にからみあった高分子系の非線形粘弾性挙動に関する研究

Yoshikawa, Katsuyuki 23 March 2020 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(工学) / 乙第13337号 / 論工博第4186号 / 新制||工||1740(附属図書館) / 京都大学大学院工学研究科材料化学専攻 / (主査)教授 瀧川 敏算, 教授 中村 洋, 教授 古賀 毅 / 学位規則第4条第2項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
247

Vliv nízkoteplotní plazmy na zlepšení keramické technologie / Influence of low-temperature plasma on enhaced ceramic processing

Rolek, Ondřej January 2017 (has links)
This masters’s thesis contains literary research about basic shaping methods of ceramic materials concerning the slip casting method. In addition, stabilization of ceramic slips, drying of ceramic green bodies and their subsequent sintering are described. This thesis also includes a description of plasma technology, including DCBD (Diffuse Coplanar Barrier Discharge) technology. In experimental part of this thesis the Al2O3 powder was treated with DCBD technology. From the prepared powder, the green body was prepared by the slip casting method, which was subsequently sintered by one-step and two-step sintering. The thesis describes the methods of preparation of ceramic samples and their evaluation. Evaluated experiments have shown that plasma technology has a positive effect on the treatment of ceramic powder Al2O3. Alumina ceramic samples of high relative density ( 99%) and low grain size (
248

Řešení vybraných detailů betonových konstrukcí s využitím FRP výztuže / Design of selected details of concrete structures with embedded FRP reinforcement

Lagiň, Juraj January 2020 (has links)
The diploma thesis is devided into two levels. The Primary part of the thesis is the theoretical part, which is part of project „FV10588 – New generation of spatial prefab made from high-firm concrete with increased mechanical resistence and endurance“, realized in cooperation with Faculty of Civil Engineering at VUT university – Institute of concrete and masonry structures. The project deals with frame corners in the form of steel and composite reinforcement which will compared through experiments and various kind of calculate proceedings. The secondary part of thesis focuses on the static-design project of cooling reservoir, placed under the ground, while is stressed by temperature. The reinforcement of the construction is realized in two ways – steel and composite reinforcement with their effectivity compared.
249

Nápravový samosvorný diferenciál / Axle Limited-Slip Differential

Csémi, András January 2020 (has links)
The topic of this master‘s thesis is the axle Limited-slip Differential. The first part is devoted to the description of types of differentials open, locked or self-locking. The next part describes the procedure of creating a mathematical model for the simulation of vehicle movement based on input parameters and subsequent comparison of vehicle behavior with open and locked differential. The final part of the work based on data obtained from the model with a Limited-slip Differential is devoted to the design of a differential for a vehicle with one driven axle.
250

Vliv podvozku na energetické a výkonnostní parametry traktorů / The influence of the chassis to the power and performance characteristics of tractors

Rašovská, Hana January 2014 (has links)
This master thesis deals with the influence of the type of tractor chassis on its utility properties. For the rating were used tractors John Deere 8 – series with wheel and track chassis, equipped with the same engine and gearbox, which were carried out for laboratory and field tests. The aim of laboratory tests was the exclusion of the difference in engine power of both tractors and the aim of field tests was to evaluate the drawbar properties of tractors with a different type of chassis. The reference parameter was especially drawbar pull, further drawbar power, slip and fuel consumption. Based on the tabular and graphical elaboration of the measured values were evaluated results.

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