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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.
51

Relações imprecisas : a fotografia e seu referente, desenho e fotografia

Hamerski, Claudia Inês January 2014 (has links)
A presente pesquisa consiste em uma reflexão sobre os trabalhos realizados entre os anos de 2012 a 2014. A produção parte da observação de uma presença na paisagem urbana marcada pela resistência de pequenas vegetações, consideradas ervas daninhas, que insistem em sobreviver. Utilizando a articulação entre fotografia e desenho, procuro apresentar possíveis vistas da cidade explorando essas micropaisagens e reapresentando-as sob outra perspectiva pelo uso da ampliação e passagem dos meios. Perpassam questões referentes ao trânsito entre as linguagens e o caráter ficcional atribuído às imagens ao produzir um deslocamento do referente pelo deslocamento do meio. São ressaltadas, ao final, mudanças e embates vivenciados ao longo do processo de instauração dos trabalhos e desenvolvimento da pesquisa, questões ainda em suspensão, e possíveis reverberações a partir da realização deste estudo. / The research in question consists in a reflection about the works made between 2012 and 2014. The production starts from the observation of a presence in the urban landscape, characterized by little vegetations resistances, considered weeds, that insist in survive. Using an articulation between photography and draw, I intent to present possible city’s views, exploiting these micro-landscapes and resubmitting them under other perspective by the use of amplification and passage between medias. It brings questions about the traffic between languages and the fictional character devoted to images when producing a displacement of the referral by the environment displacement. At the end, the changes and handling lived along the work’s instauration process, research’s development and possible reverberations from this study are highlighted, questions still in suspension.
52

Proposta de modelagem e simulação para análise de distorção harmônica

Silva, Mauren Pomalis Coelho da January 2014 (has links)
Este trabalho apresenta um estudo de Qualidade de Energia Elétrica (QEE) no sistema elétrico industrial de uma concessionária geradora de energia elétrica do Brasil. O estudo teve enfoque na distorção harmônica gerada nos serviços auxiliares da usina termoelétrica. Para tanto, foi necessária a simulação e análise da planta da termoelétrica, com atenção nos serviços auxiliares pertencentes a ela, devido aos altos níveis de distorções harmônicas registrados. A simulação foi feita com o programa ATP (Alternative Transients Program) no domínio do tempo, através de sua interface gráfica, o ATP Draw. Nele foram modelados os principais componentes que pertencem ao Sistema Elétrico de Potência (SEP) em questão, como geradores, transformadores, linhas e cargas não lineares. Com a modelagem do SEP da termoelétrica, é possível determinar os níveis da distorção harmônica em diversos locais da planta, e aprofundar o estudo para que seja possível fazer a mitigação desses distúrbios. A diminuição da distorção harmônica junto ao aumento do fator de potência permite um melhor desempenho da usina, aumentando a faturamento da empresa através do aumento da energia entregue ao sistema elétrico. / This dissertation presents a study of Power Quality in an electrical system of a thermoelectric power plant in Brazil. The study focused on the harmonic distortion generated in the auxiliary services of the plant. Therefore, it was necessary to simulate and analyze the thermal plant, with attention to auxiliary services belonging to it, due to high levels of harmonic distortion registered. The simulation was performed using the ATP (Alternative Transients Program) in the time domain through its interface, the ATP Draw. It were modeled the main components that belong to the Power System in question, such as generators, transformers, lines and non-linear loads. With the modeling of the thermoelectric plant, is possible to determine the levels of harmonic distortion at various locations within the plant. The reduction of harmonic distortion along with the increase of power factor allows a better plant performance, increasing company revenue by increasing the energy delivered to the electrical system.
53

Relações imprecisas : a fotografia e seu referente, desenho e fotografia

Hamerski, Claudia Inês January 2014 (has links)
A presente pesquisa consiste em uma reflexão sobre os trabalhos realizados entre os anos de 2012 a 2014. A produção parte da observação de uma presença na paisagem urbana marcada pela resistência de pequenas vegetações, consideradas ervas daninhas, que insistem em sobreviver. Utilizando a articulação entre fotografia e desenho, procuro apresentar possíveis vistas da cidade explorando essas micropaisagens e reapresentando-as sob outra perspectiva pelo uso da ampliação e passagem dos meios. Perpassam questões referentes ao trânsito entre as linguagens e o caráter ficcional atribuído às imagens ao produzir um deslocamento do referente pelo deslocamento do meio. São ressaltadas, ao final, mudanças e embates vivenciados ao longo do processo de instauração dos trabalhos e desenvolvimento da pesquisa, questões ainda em suspensão, e possíveis reverberações a partir da realização deste estudo. / The research in question consists in a reflection about the works made between 2012 and 2014. The production starts from the observation of a presence in the urban landscape, characterized by little vegetations resistances, considered weeds, that insist in survive. Using an articulation between photography and draw, I intent to present possible city’s views, exploiting these micro-landscapes and resubmitting them under other perspective by the use of amplification and passage between medias. It brings questions about the traffic between languages and the fictional character devoted to images when producing a displacement of the referral by the environment displacement. At the end, the changes and handling lived along the work’s instauration process, research’s development and possible reverberations from this study are highlighted, questions still in suspension.
54

Limitní parametry technologie ohýbání dílců z trubek / Forming limits for the bending process of tubular components

Maleček, Michal January 2015 (has links)
Currently, rotary draw bending is frequently used method in industry. Nevertheless, it has been limited for long time by different types of defects. Submitted thesis deals with the study of the influence the bending radius and wall thickness on the quality of bent. Practical part of the thesis includes experimental rotary draw bending of tubes. The work also solves determining actual values of the wall thickness; ovality, bent shapes, the section modulus in bending and the neutral axis of the tube On the basis of evaluation of criteria are then set the parameters of permissible bend
55

Manifestações expressivas e simbólicas / Expressive and symbolic expressions

Moraes, Ana Luisa Fernandes de 02 November 2011 (has links)
Orientadores: Adilson Nascimento de Jesus, Ana Angélica Medeiros Albano / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação / Made available in DSpace on 2018-08-18T11:25:00Z (GMT). No. of bitstreams: 1 Moraes_AnaLuisaFernandesde_M.pdf: 6039133 bytes, checksum: 4667737c67a9f880b84f2c7d455244e0 (MD5) Previous issue date: 2011 / Resumo: O objetivo da pesquisa foi buscar expressões que revelassem uma experiência simbólica através de práticas corporais oferecidas tanto aos internos de uma instituição psiquiátrica como para mulheres universitárias. O método utilizado no trabalho foi qualitativo e baseado nos estudos de Eloísa Penna (2005, 2007). Os dados dos internos da clínica psiquiátrica vieram através da atuação profissional da pesquisadora durante o período de três anos. E para as mulheres universitárias foram realizados dezesseis encontros. Em ambos os grupos foram utilizados recursos expressivos, como a criação em dança e o desenho livre. Dentre todos os participantes, foram selecionados três casos para seguir com as análises. Os dois primeiros casos, que são os do grupo dos internos da instituição psiquiátrica, mostraram a expressão de imagens circulares que revelaram uma saudade do estado primordial vivido no primeiro ano de vida. Também associou tais manifestações com o arquétipo do Self e sendo uma tendência do inconsciente em compensar o caos vigente na consciência. O terceiro caso corresponde ao grupo de improvisação em dança e com o foco nas imagens de árvores que foram desenhadas por uma participante ao longo dos encontros. Através destas imagens, foi compreendida a árvore novamente como um arquétipo do Self. Também percebeu na pesquisa que os símbolos, por serem abstratos, apenas existem quando se notam suas manifestações no tempo presente. Além do mais que jamais é possível expressá-los de maneira satisfatória, já que a própria linguagem acaba perturbando a verdadeira essência de um símbolo. / Abstract: The research objective was to seek expressions that reveal a symbolic experience through bodily practices offered to interne in a psychiatric institution as college women. The method used in the study was qualitative and based on studies of Eloisa Penna (2005, 2007). The data of inmates of the psychiatric clinic came through the researcher's professional performance during the period of three years. And for the college women were held sixteen meetings. In both groups significant resources were used as dance creation and drawing freedom. Among all participants, we select three cases to proceed with the analysis. The first two cases, which are the group of inmates of the psychiatric institution, showed the expression of circular images that revealed a longing for the primordial state lived in the first year of life. Also associated with such manifestations of the archetypal Self and the unconscious is a tendency to compensate for the chaos prevailing in consciousness. The third case corresponds to group improvisation in dance and with the focus on images of trees that were drawn by a participant during the meetings. Through these images it was understood the tree again as an archetype of the Self. It has also been realized in the research that the symbols only exist when we perceive its manifestation in the present time, due to the fact they are abstract. Furthermore we can never express them in a satisfactory manner, since the language itself ends up disturbing the real essence of a symbol. / Mestrado / Educação, Conhecimento, Linguagem e Arte / Mestre em Educação
56

Analýza procesu ohybu trubky / Analysis of Tube Bending Process

Šrom, Jan January 2017 (has links)
Master thesis analyzes rotary draw bending of the tubes without using a mandrel. Bending process is accompanied by many defects due to large displacement of formed material. One of the major defects is flattering of the cross section also called ovality. In order to decrease ovality comes up a proposal of the changes to the tool design. Modifications of tool’s geometry are numerically analyzed by finite element method in software ANSYS. According to the results of the simulations an optimized pressure die is manufactured. Several experimental tests are accomplished to verify the effect of the optimized tool design. Approximately 100 bends confirm a decrease of ovality using modified pressure die.
57

A performance and energy evaluation of a dye drawn forward osmosis (FO) system for the textile industry

Rahman, Mohammed January 2020 (has links)
Thesis (MEng (Chemical Engineering))--Cape Peninsula University of Technology, 2020 / Continuous growth in the world population has raised significant fears with regards to the sustainability of energy and water resources. Globally, water is an indispensable resource as it is essential for the sustenance of human, animal and plant life. Water is essential for all forms of life and plays a pivotal role in economic growth. The textile industry is one of the greatest consumers of water, it is, therefore, necessary to effectively treat the large amounts of wastewater before discharge to the environment. It is estimated that annually, more than 700,000-tonnes of textile wastewater is produced by the dyeing industry. Textile wastewater is generally characterised by electrolytes, suspended solids, mineral oils and multiple textile dyes, and has therefore been classified as one of the most polluting wastewaters. These dyes are toxic and, in most cases, are not biodegradable. The presence of very small amounts (i.e. < 1 ppm) of dyes in water has aesthetic impacts and is thus undesirable. It is, therefore, necessary to treat textile wastewater before discharging. Currently, membrane technology is widely used for wastewater treatment, as well as water purification. Forward osmosis (FO) is a promising technology for both these applications. FO is characterised by the flow of water through a semipermeable membrane from a feed solution (FS) characterised by the low solute concentration or low osmotic pressure (OP) to a draw solution (DS) characterised by the high solute concentration or high OP, due to the OP gradient across the membrane. The FO process eliminates the need for high hydraulic pressure, as required in traditional membrane technologies, and also has low fouling tendencies. Furthermore, FO has the advantage of lower energy requirements and membrane replacement costs. However, there are still many disadvantages such as reverse solute flux (RSF), membrane fouling, and concentration polarisation (CP) amongst others that still need to be addressed. Therefore, more research needs to be done in light of these limitations to better understand and mitigate these limitations to increase the effectiveness and efficiency of the FO process. This study aimed to evaluate a dye-driven FO system for the reclamation of water from textile wastewater and synthetic brackish water (BW5) by investigating the effects of membrane orientation, system flowrate, change in DS, and membrane fouling on the FO systems performance and energy consumption. The FS used was BW5 with sodium chloride (NaCl) content of 5 g/L whereas Reactive Black 5 (i.e. a reactive dye) and Maxilon Blue GRL (i.e. a basic dye) dyes were used as a DS, respectively. The membrane utilised was a cellulose triacetate (CTA) membrane and was tested in FO mode and pressure retarded osmosis (PRO) mode whilst the system flowrate was adjusted to 400, 500 and 600 mL/min, respectively. Experiments were performed using a bench-scale FO setup which comprised of an FO membrane cell, a double-head variable speed peristaltic pump, a digital scale, two reservoirs for the FS and DS, respectively, a digital multiparameter meter and a digital electrical multimeter to measure system energy consumption. Each experiment comprised of six steps: baseline 1 (membrane control), main experiment (dye-driven FO experiment), baseline 2 (membrane control repeat), membrane cleaning, membrane integrity (membrane damage dye identification) and membrane cleaning (preparation for next experiment). The baseline 1 and baseline 2 experiments operated for 3 h whilst each membrane cleaning procedure operated for 30 min. The main experiments operated for 5 h in the FO mode and 4 h in PRO mode whilst the membrane integrity experiments operated until a minimum of 10 mL water was recovered. Results showed that the PRO mode achieved both higher forward flux (𝐽𝑤) (i.e. 8.87, 8.71 and 9.13 L/m2.h for flowrates of 400, 500 and 600 ml/min) and water recovery (𝑅𝑒) rates compared to FO mode (i.e. 6.60, 6.88 and 7.58 L/m2.h for flowrates of 400, 500 and 600 ml/min). The variation of flowrates had little to no influence on the 𝐽𝑤, 𝐽𝑠 and 𝑅𝑒 of the system. The system consumed less energy in PRO mode (i.e. 381 kWh/m3 average consumption for all three flowrates) than FO mode (i.e. 417 kWh/m3 average consumption for all three flowrates). It was also observed that at a higher DS 𝑂𝑃, the system consumed less energy. Therefore, selecting an optimum initial 𝑂𝑃 is essential for a FO process to minimise the pumping energy. Furthermore, a change in DS from Reactive Black 5 dye to Maxilon Blue GRL dye had no significant impact on the system performance and energy consumption. In this study, no significant membrane fouling was observed, however, minute traces of fouling in the form of foreign functional groups could be observed in the attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) spectrums of the used membranes. Additionally, the observation of negligible changes in baseline 2 (membrane control) Re and Jw results suggested the possible occurrence of membrane fouling during the main experiment (dye-driven FO system).
58

Influence of microphytic crusts on selected soil physical and hydrologic properties in the Hartnet Draw, Capitol Reef National Park, Utah.

Williams, John Dana 01 May 1993 (has links)
Microphytic crust influences on selected physical and hydrologic soil properties were examined at one location in Capitol Reef National Park, Utah. Designed experiments were conducted in a sandy loam soil where microphytic crusts were present without the concomitant development of confounding physical or chemical soil conditions. Three treatments were used for all experiments: control, chemically killed (microphytes killed but left in place), and scalped (microphytic crusts mechanically removed). A portable wind tunnel was used to deter-nine if microphytic crusts contribute to soil stability and reduce the erosive effect of wind. Significantly lower threshold friction velocity and greater wind-entrained material were recorded in the scalped treatment than in the control or chemically killed treatments. These results are evidence that microphytic crusts significantly contribute to reducing the erosive force of wind at this site. A dripper system was used in situ to determine if microphytic crusts influence effective saturated hydraulic conductivity. There were no significant differences among treatments. This result is evidence that microphytic crusts have a minimal influence, if any, on effective saturated hydraulic conductivity at this site. Rainfall simulation was used to determine if microphytic crusts influence hydrologic properties of time to ponding, time to runoff, and infiltration capacity. Rainfall was simulated for 90 minutes after runoff began. Simulated rainfall also was used to determine if microphytic crusts influence interrill erosion. Time to ponding and time to runoff were significantly shorter in the control and chemically killed treatments than in the scalped treatment. However, infiltration capacity was not significantly different among treatments during any five-minute period within the 90 minutes that runoff occurred. Microphytic crusts apparently reduce initial entry of water into the soil profile; however, once infiltration has begun, they do not inhibit or enhance infiltration capacity at this site. Interrill erosion was nearly constant from the control treatment throughout simulated rainfall events. Significantly greater interrill erosion occurred in the chemically killed treatment compared to control and scalped treatments. Interrill erosion in the scalped treatment was significantly greater than in the control treatment after 30 minutes and through 90 minutes. These results are evidence that microphytic crusts, when composed of living, undisturbed microphytes, resist the erosive effect of rainfall and contribute to the soil stability of this site.
59

Language development, anxiety and early socialization processes

Wait, Mary Eleanor January 1965 (has links)
Thesis (Ed.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / PURPOSE OF THE STUDY.-- To test the hypothesis that poor language achievement in children of average to better intelligence and middle class background is attributable to basic anxiety. PROCESS EMPLOYED.-- To a group of fourth-grade children of such background and intelligence there were administered a language test (composed of the subtests Information and Vocabulary of the Wechsler Intelligence Scale for Children) and three projective tests (the Gilmore Sentence Completion Test, the Bellak Children's Apperception Test, and the Machover Draw-A-Person Test) for the purpose of ascertaining the nature of the relationship, if any, between their language achievement and the degree of basic anxiety manifested in their responses to the projective tests. The number of Freudian defense mechanisms expressed in their responses to the projective tests was designated as the index of anxiety. The defense mechanisms used were selected, defined, and a glossary for their interpretations set up only after consultations with a group of child psychiatrists and child psychologists in practice in the Boston area. Their consensus of opinion was that these defense mechanisms were the ones most likely to be employed by children in this age group. They consist of the following: denial, introjection-incorporation, projection, regression, reaction-formation, displacement, and isolation. The scores resulting from the language test were divided into a High and a Low Language Group. They were then correlated with the defense mechanisms scores obtained from each of the three projective tests and with the total defense mechanisms scores resulting from all three projective tests. FINDINGS.-- The correlation of the High and Low Language Groups, taken as one, revealed no significant relationship between poor language achievement and high anxiety but did indicate a trend in the opposite direction from the one that had been hypothesized. Analysis of the verbal responses revealed that Verbal Output was the deciding factor with regard to the number of defense mechanisms expressed. However, this phenomenon was not considered as negating the original hypothesis but rather as pointing to the possibility that anxiety not only inhibited language achievement but inhibited the expression of verbal defense mechanisms as well. The separate correlation of High and Low Language Group scores with defense mechanisms scores did indicate a trend towards the hypothesized direction but not to a significant degree. The correlation of the defense mechanisms expressed in the drawings for the Draw-A-Person Test likewise failed to establish the predicted inverse relationship between anxiety and language achievement. Here again, production automatically controlled the expression of defense mechanisms, thus bringing about a situation in which those subjects who did not complete their drawings earned the lowest defense mechanisms scores. INDICATIONS OF THE STUDY.-- (1) That a more sensitive language test is needed for the purpose of establishing sharper differentiations between language achievers as a preliminary basis for similar studies. (2) That the study of the types of language employed by the subjects might be more revealing of anxiety than the utilizing of defense mechanisms as indicators of anxiety. (3) That the limiting agent in the non-verbal projective test employed (the Machover Draw-A-Person Test) may have been the anxious individual's self image. This would suggest the need for devising ways of uncovering the self image and using it as one index of anxiety. (4) That there may be a significant relationship among the self image, the type of verbal output, the quantity of verbal output, and basic anxiety. / 2031-01-01
60

The Effects of Implementation Intentions on Responses to Needle Images in those with High Needle Fear

Ankawi, Brett 24 August 2015 (has links)
No description available.

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