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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.
471

A formalização fonético-fonológica da percepção de plosivas surdas sob múltiplas manipulações de voice onset time (VOT) por brasileiros e americanos à luz do modelo "Bhipon"

MOTTA-AVILA, Camila 21 December 2017 (has links)
Submitted by Cristiane Chim (cristiane.chim@ucpel.edu.br) on 2018-07-16T12:23:03Z No. of bitstreams: 1 Camila Motta Avila.pdf: 5908666 bytes, checksum: fec1aaf83edeb30b980911d427091061 (MD5) / Made available in DSpace on 2018-07-16T12:23:03Z (GMT). No. of bitstreams: 1 Camila Motta Avila.pdf: 5908666 bytes, checksum: fec1aaf83edeb30b980911d427091061 (MD5) Previous issue date: 2017-12-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES# / #2075167498588264571# / #600 / This Master’s Dissertation had as its main goal analyzing and formalizing how Brazilian learners of English language (L2) and Americans identify and discriminate the voicing patterns for plosive consonants under artificial manipulation in English monossilabic words. Americans normally follow the acoustic cue Voice Onset Time (VOT) to differentiate voiced plosives from voiceless ones. The VOT is measured in milisseconds and can be classified into three different categories (LISKER & ABRAMSON, 1964): negative VOT (for /b/, /d/ and /g/ in Portuguese); short-lag VOT (for /p/, /t/, /k/ in Portuguese and /b/, /d/, /g/ in English) and long-lag or positive VOT (for [ph], [th], [kh] in English). Previous studies (ALVES, BARATZ e MOTTA, 2012; SCHWARTZHAUPT, ALVES &FONTES, 2015; ALVES & MOTTA, 2014; MOTTA, 2014; ALVES & ZIMMER, 2015) demonstrated that the manipulation of VOT can result into different types of perceptual behaviour, depending on the group analyzed: Americans tend to follow this cue to attribute voicing patterns to consonants, while Brazilians tend to follow the voicing patters stablished for their L1. In order to analyze the perception in L2, this Dissertation was based on Speech Learning Model (SLM) – (FLEGE, 1995) and Perceptual Assimilation Model – L2 (PAM-L2) – (BEST e TYLER, 2007) studies. To investigate how perception was processed in Americans, explanations in Kent and Read (2015), Gussenhoven and Jacobs (2004), Matzenauer (2015) and Boersma, Escudero and Hayes (2003) were found. The method consisted of two perceptual tests: (a) Identification Test, (b) Discrimination Test. Both tests were designed with artificially manipulated stimuli. The types (pee, pit, tick, tip, kit, kill) were CVC (where V was a high vowel /ɪ/ or /i/). Each one of them was multiply manipulated, generating five tokens from one original type. This manipulation was gradually performed, in 25% layers, aiming to achieve the zero artificial VOT pattern. The Identification Test was designed with 60 target words and 12 distractors, resulting in 72 tokens per participant. The Discrimination Test was designed with 36 target trials and 9 catch-trials, in a total of 45 trials per participant. To summarize, results show that Americans can be considered to be more perceptually sensitive to the multiple VOT manipulation than Brazilians, who normally tend to follow their L1 way of attributing voicing patterns to plosives, regardless their proficiency level in English (basic, intermediate or advanced). In addition, different phonetic tresholds were found in each analyzed group and in each place of articulation observed (bilabial, alveolar, velar). Finally, this study tries to offer a formalization for perceptual grammars in each group, based on Bi-directional Phonology OT Model (BiPhon). It is expected that this study, its detailed data description and theoretical observations can contribute to and makefurther academic studies possible. / Esta Dissertação de Mestrado teve como principal objetivo analisar e formalizar de que forma brasileiros aprendizes de inglês (L2) e americanos identificam e discriminam o vozeamento das consoantes plosivas iniciais da língua inglesa sob múltiplas manipulações em palavras monossilábicas. Na língua inglesa, para a diferenciação de vozeamento, tem-se como principal pista acústica a aspiração, que pode ser medida a partir dos valores de Voice Onset Time (VOT). O VOT é medido em milissegundos e pode ser classificado em 3 diferentes padrões (LISKER & ABRAMSON, 1964): VOT NEGATIVO (que se realiza foneticamente em português em /b/, /d/ e /g/); VOT ZERO, (que se realiza como /p/, /t/ e /k/ no português e /b/, /d/ e /g/ no inglês) e o VOT POSITIVO (encontrado em [ph], [th] e [kh] no inglês). Estudos anteriores (ALVES, BARATZ e MOTTA, 2012; SCHWARTZHAUPT, ALVES &FONTES, 2015; ALVES & MOTTA, 2014; MOTTA, 2014; ALVES & ZIMMER, 2015) demonstraram que a manipulação da pista acústica VOT resulta em comportamentos perceptuais diferenciados de acordo com a natureza do participante: americanos tendem a seguir a pista acústica em questão ao atribuir ou não vozeamento para as consoantes plosivas, ao passo que os brasileiros continuam a seguir os padrões de vozeamento previstos para a sua L1. Para dar conta da percepção em inglês como L2, este trabalho fundamentou-se, basicamente, nos modelos perceptuais Speech Learning Model (SLM) – (FLEGE, 1995) e Perceptual Assimilation Model – L2 (PAM-L2) – (BEST e TYLER, 2007). Para analisar a percepção dos participantes americanos, buscaram-se explicações em Kent e Read (2015), Gussenhoven e Jacobs (2004), Matzenauer (2015) e Boersma, Escudero e Hayes (2003). O método aplicado neste estudo consistiu em dois testes de percepção: (a) Teste de Identificação, (b) Teste de Discriminação. Ambos foram montados com estímulos de palavras monossilábicas da língua inglesa (CVC), sendo V /ɪ/ ou /i/. Cada type (pee, pit, tick, tip, kit, kill) passou por manipulação múltipla da pista acústica VOT, gerando 5 tokens cada um. Tal manipulação se deu de forma gradual em camadas de 25%, objetivando-se alcançar o padrão de VOT zero artificial. O design do Teste de Identificação contou com 60 palavras-alvo e 12 distratoras, somando um total de 72 tokens por participante. O design do Teste de Discriminação, que teve por objetivo contrastar diferentes camadas de VOT entre si, contou com 36 tríades do tipo AxB e 9 catch-trials, somando 45 tríades por participante. Sucintamente, os resultados apresentados demonstraram que os participantes americanos são mais sensíveis ao corte da pista acústica VOT do que os participantes brasileiros, independentemente do nível de proficiência em língua inglesa (básico, intermediário e avançado). Além disso, limiares fonéticos distintos foram encontrados em cada um dos grupos analisados e em cada ponto de articulação observado (bilabial, alveolar, velar). Finalmente, propôs-se uma formalização da percepção de ambos os grupos para cada consoante analisada baseando-se no Modelo de OT Bidirecional (BiPhon), proposto por Boersma (2009) e Boersma e Hamman (2011). Espera-se, com este estudo, que a descrição detalhada dos dados e a reflexão teórica possam contribuir à Academia e possibilitar estudos futuros.
472

Algoritmo enxame de partículas discreto para coordenação de relés direcionais de sobrecorrente em sistemas elétricos de potência / Discrete particle swarm algorithm for directional overcurrent relays coordination in electric power system

Bernardes, Wellington Maycon Santos 26 March 2013 (has links)
Este trabalho propõe uma metodologia baseada em técnicas inteligentes capaz de fornecer uma coordenação otimizada de relés direcionais de sobrecorrente instalados em sistemas de energia elétrica. O problema é modelado como um caso de programação não linear inteira mista, em que os relés permitem ajustes discretizados de múltiplos de tempo e/ou múltiplos de corrente. A solução do problema de otimização correspondente é obtida através de uma metaheurística nomeada como Discrete Particle Swarm Optimization. Na literatura técnico-científica esse problema geralmente é linearizado e aplicam-se arredondamentos das variáveis discretas. Na metodologia proposta, as variáveis discretas são tratadas adequadamente para utilização na metaheurística e são apresentados os resultados que foram comparados com os obtidos pelo modelo clássico de otimização implementado no General Algebraic Modeling System (GAMS). Tendo em vista os aspectos observados, o método permite ao engenheiro de proteção ter um subsídio adicional na tarefa da coordenação dos relés direcionais de sobrecorrente, disponibilizando uma técnica eficaz e de fácil aplicabilidade ao sistema elétrico a ser protegido, independentemente da topologia e condição operacional. / This work proposes a methodology that based on intelligent technique to obtain an optimized coordination of directional overcurrent relays in electric power systems. The problem is modeled as a mixed integer nonlinear problem, because the relays allows a discrete setting of time and/or current multipliers. The solution of the proposed optimization problem is obtained from the proposed metaheuristic named as Discrete Particle Swarm Optimization. In scientific and technical literature this problem is usually linearized and discrete variables are rounded off. In the proposed method, the discrete variables are modeled adequately in the metaheuristic and the results are compared to the classical optimization solvers implemented in General Algebraic Modeling System (GAMS). The method provides an important method for helping the engineers in to coordinate directional overcurrent relays in a very optimized way. It has high potential for the application to realistic systems, regardless of topology and operating condition.
473

Vysokotlaký servopohon regulačních ventilů parní turbíny / High Pressure Actuator of Valves for the Steam Turbine

Gregor, Kamil January 2016 (has links)
A high-pressure actuator of regulatory valves of steam turbines is designed in this thesis. The first part of the thesis discusses different types of steam turbines and the alternatives of their regulation. In the second part, one particular arrangment, with directional control valve, double poppet valve and hydraulic curtain, is described. Technical documentation including the conceptual proposal, the choice of individual components and all calculations is the output of this thesis. Drawing documentation of the set and drawing documentation required for the construction of the hydraulic block is attached.
474

Efficient broadband antenna array processing using the discrete fourier form transform

Sayyah Jahromi, Mohammad Reza, Information Technology & Electrical Engineering, Australian Defence Force Academy, UNSW January 2005 (has links)
Processing of broadband signals induced on an antenna array using a tapped delay line filter and a set of steering delays has two problems. Firstly one needs to manipulate large matrices to estimate the filter coefficients. Secondly the use of steering delays is not only cumbersome but implementation errors cause loss of system performance. This thesis looks at both of these problems and presents elegant solutions by developing and studying a design method referred to as the DFT method, which does not require steering delays and is computationally less demanding compared to existing methods. Specifically the thesis studies and compares the performance of a time domain element space beamformer using the proposed method and that using an existing method, and develops the DFT method when the processor is implemented in partitioned form. The study presented in the thesis shows that the processors using the DFT method are robust to look direction errors and require less computation than that using the existing method for comparable performance. The thesis further introduces a broadband beamformer design which does not require any steering delays between the sensors and the tapped delay line section as is presently the case. It has the capability of steering the array in an arbitrary direction with a specified frequency response in the look direction while canceling unwanted uncorrelated interferences. The thesis presents and compares the performance of a number of techniques to synthesize an antenna pattern of a broadband array. These techniques are designed to produce isolated point nulls as well as broad sector nulls and to eliminate the need for the steering delays. Two of the pattern synthesis techniques presented in the thesis allow optimization against unwanted interferences in unknown directions. The techniques allow formulation of a beamforming problem such that the processor is not only able to place nulls in specified directions but also able to cancel directional interferences in unknown directions along with a specified frequency response in the look direction over a band of interest. The thesis also presents a set of directional constraints such that one does not need steering delays and an array can be constrained in an arbitrary direction with a specified frequency response. The constraints presented in the thesis are simple to implement. Based on these constraints a pattern synthesis technique for broadband antenna array is also presented.
475

以漢語趨向動詞「起來」、「下去」、「上來」為例的語法化研究 / On Mandarin Directional Verbs Qi-lai, Xia-Qu, and Shang-lai: A Reflection of Grammaticalization

李陳福, Li, Chen-Fu Alfred Unknown Date (has links)
本篇論文引用Hopper在1993年所提出的五項原則,論證漢語中「起來」、「下去」、「上來」的多義現象是反映語法化的現象。在「起來」、「下去」、「上來」語法化的過程中,可以發現許多語意和語法的痕跡,例如語意選擇的限制、受詞位置的限制、受詞限定的要求、與完成貌時貌標記使用的限制。根據Lehmann 1991年的研究,這些痕跡說明「起來」、「下去」、「上來」在語法化的過程中是由「子句中」向「子句間」變動。這樣的語意變動主要來自於概念上由空間向時間的比喻轉換。除此之外,在「起來」、「下去」、「上來」的句子中,這樣的轉換還受到不同的語意角色要求所限制。 / This thesis applies Hopper*s Principles (1993) to assert that the semantic varieties of Mandarin directional verbs qi-lai, xia-qu, and shang-lai are reflections of grammaticalization. The grammaticalization of Mandarin qi-lai, xia-qu, and shang-lai has left traces on selectional restriction, syntactic constraints on object positions, object definiteness, and requirements of perfective aspect marker. Based on Lehmann (1991), these traces lead to the conclusion that Mandarin qi-lai, xia-qu, and shang-lai shift from clause-internal to cross-clause grammaticalization. The semantic shifts of Mandarin qi-lai, xia-qu, and shang-lai are considered to be motivated by SPACE-to-TIME metaphorical transfer. The transfer is also constrained by theta-role requirements.
476

中國古代風神崇拜研究-從先殷到漢 / WIND SPIRIT WORSHIP IN ANCIENT CHINA

魏慈德, Wei, Tzu Te Unknown Date (has links)
本文廣泛的探討了從遠古到秦漢時期先民對風這一自然現象的崇拜意識,初步將古人的風神崇拜原因分為兩大類,包括因為處於地理環境上的多風性質或伴隨風而來的天象而成為風神化身的自然神崇拜和季風氣候下風向和季節的必然性所衍申出的風向與時節對應的具神聖性之傳統觀念。並指出後者是古代風神崇拜的主流,從早期的利用瞽者聽風以判定時節到刻有四風和代表四季徵象的四方風名甲骨,更衍成以風向與時節的對應與否來判定兵家攻守或醫家虛實的依據都是這一支風神觀念極度發展的結果。   本文在探討中國古代風神崇拜之餘,並從文字學的角度論風字的產生與演變過程,其次更由四方風名甲骨片的文字指出了經典上文字的來由及歷來經說不當之處。 / This is a comprehensive discussion on early man's worship and consciousness of the natural phenomanon of wind,from ancient times until the Han period.First of all the reason for early man 's wind spirit worship are divided into two main categories : includingthe natural spirit worship of the many types of wind in an inhabited geographical environment or the natural phenomena which accompany wind and become the embodiment of wind spirit; and the traditional concepts and the effect of the season and climate on the direction;the inevitability of the development of wind direction and the corresponding times of the spirit divinity moreover,the discussion point out that the latter is main trend of ancient wind spirit worship, from the use of the blind in early times to feel for wind to judge the times and season,to the (four corners wind name) oracle bone carved with the four winds and the symbol of four season,it is further developed to the corresponding non coprespondance of wind dire- ction and times to determine military manoeuvres or the bases for madical fact. These are all the results of the extreme degree of development of this branch of wind spirit concept.   This discussion,in addition to exploring ancient wind spirit worship in China,also discusses,from a linguistic point of view,the emergence and the development process of the character wind furthermore,the discussion uses the words carved on the (four corners wind name) oracle bone fragment to point out the origin of characters contained in the classics, and also to point out any in appropriate areas which have existed until now in the ex-planation of the classics.
477

Field Oriented Control Of A Permanent Magnet Synchronous Motor Using Space Vector Modulated Direct Ac-ac Matrix Converter

Yildirim, Dogan 01 May 2012 (has links) (PDF)
The study designs and constructs a three-phase to three-phase direct AC&ndash / AC matrix converter based surface mounted permanent magnet synchronous motor (PMSM) drive system. First, the matrix converter topologies are analyzed and the state-space equations describing the system have been derived in terms of the input and output variables. After that, matrix converter commutation and modulation methods are investigated. A four-step commutation technique based on output current direction provides safe commutation between the matrix converter switches. Then, the matrix converter is simulated for both the open-loop and the closed-loop control. For the closed-loop control, a current regulator (PI controller) controls the output currents and their phase angles. Advanced pulse width modulation and control techniques, such as space vector pulse width modulation and field oriented control, have been used for the closed-loop control of the system. Next, a model of diode-rectified two-level voltage source inverter is developed for simulations. A comparative study of indirect space vector modulated direct matrix converter and space vector modulated diode-rectified two-level voltage source inverter is given in terms of input/output waveforms to verify that the matrix converter fulfills the two-level voltage source inverter operation. Following the verification of matrix converter operation comparing with the diode-rectified two-level voltage source inverter, the simulation model of permanent magnet motor drive system is implemented. Also, a direct matrix converter prototype is constructed for experimental verifications of the results. As a first step in experimental works, filter types are investigated and a three-phase input filter is constructed to reduce the harmonic pollution. Then, direct matrix converter power circuitry and gate-driver circuitry are designed and constructed. To control the matrix switches, the control algorithm is implemented using a DSP and a FPGA. This digital control system measures the output currents and the input voltages with the aid of sensors and controls the matrix converter switches to produce the required PWM pattern to synthesize the reference input current and output voltage vectors, as well. Finally, the simulation results are tested and supported by laboratory experiments involving both an R-L load and a permanent magnet synchronous motor load. During the tests, the line-to-line supply voltage is set to 26 V peak value and a 400 V/3.5 kW surface mounted permanent magnet motor is used.
478

Violence conjugale et détresse psychologique chez les jeunes couples : analyse de l'effet modérateur du soutien social

Fortin, Isabel 08 1900 (has links)
Les jeunes adultes sont plus susceptibles de subir de la violence conjugale que les adultes plus âgés. Toutefois, l'effet de se confier à propos de la violence subie sur la santé mentale est peu connu. L'objectif de cette étude est d'explorer les liens entre la violence conjugale, le soutien social et la détresse psychologique selon le sexe dans un échantillon de 233 jeunes couples. Les résultats indiquent que, pour les femmes, la fréquence de la violence psychologique subie, mais pas celle de la violence physique, était positivement associée à la détresse psychologique. Pour ces femmes, recourir à un plus grand nombre de confidents diminue la force de la relation entre la violence et de leur niveau de détresse psychologique. Pour les hommes, les fréquences de la violence physique et psychologique subies étaient positivement liées à la détresse psychologique, mais contrairement aux femmes, plus ils se sont confiés à propos de la violence qu'ils ont subi, plus leur niveau de détresse est élevé. / Young adults are more likely to experience intimate partner violence (IPV) than older adults but little is known about the effect of confiding to others about the sustained violence on their mental health. The objective of this study was to explore the links between IPV, help-seeking and psychological distress by gender in a sample of 233 young couples. Our findings indicate that for women, the frequency of sustained psychological violence, but not of physical violence, was positively associated to psychological distress and that for these women, seeking help from a greater number of confidents decreased the strength of the association between violence and their level of psychological distress. Secondly, for men, the frequency of physical and psychological violence were both positively linked to psychological distress but unlike women, the more people they talked to about the violence they have sustained, the greater their level of distress was.
479

Comparative performance of ductile and damage protected bridge piers subjected to bi-directional earthquake attack

Mashiko, Naoto January 2006 (has links)
Incremental Dynamic Analysis (IDA) procedures are advanced and then applied to a quantitative risk assessment for bridge structures. This is achieved by combining IDA with site-dependent hazard-recurrence relations and damage outcomes. The IDA procedure is also developed as a way to select a critical earthquake motion record for a one-off destructive experiment. Three prototype bridge substructures are designed according to the loading and detailing requirements of New Zealand, Japan and Caltrans codes. From these designs 30 percent reduced scale specimens are constructed as part of an experimental investigation. The Pseudodynamic test is then to control on three specimens using the identified critical earthquake records. The results are presented in a probabilistic riskbased format. The differences in the seismic performance of the three different countries' design codes are examined. Each of these current seismic design codes strive for ductile behaviour of bridge substructures. Seismic response is expected to be resulting damage on structures, which may threaten post-earthquake serviceability. To overcome this major performance shortcoming, the seismic behaviour under bi-directional lateral loading is investigated for a bridge pier designed and constructed in accordance with Damage Avoidance principles. Due to the presence of steel armoured rocking interface at the base, it is demonstrated that damage can be avoided, but due to the lack of hysteresis it is necessary to add some supplemental damping. Experimental results of the armoured rocking pier under bi-directional loading are compared with a companion ductile design specimen.
480

碳排放管制對臺灣工業部門生產效率及汙染減量成本之分析 / Analysis of production efficiency and pollution abatement cost of Taiwan's industrial sector under CO2 regulation

蒲嵩杰, Pu, Song Jie Unknown Date (has links)
全球暖化已成為大多數國家近幾年所關心的議題。雖然臺灣政府於2010年5月所核定的「國家節能減碳總計畫」之中,儘管減量目標及原則業已確立,但未充分探討各別產業的面臨碳排放管制時所造成的影響,因此,臺灣各產業或次部門究竟應承擔多大的減量責任仍是混沌不明。 為了更清楚瞭解碳排放管制對於臺灣工業部門之各產業的影響,本文以方向性距離函數,估算工業部門中14個產業367家上市櫃、興櫃和公開發行公司於2005年至2010年,在不同電力消費所產生的CO2之責任歸屬情況下之生產效率及汙染減量成本,以反映各產業於管制下的機會成本,便於鎖定某些產業或公司,來賦予減量責任。結果發現,各產業在實施碳排放管制後的效率水準,會高於未實施碳排放管制時的效率水準,且各產業的平均總汙染減量成本與每噸二氧化碳減量成本相差甚大。而臺灣尚未通過相關法規以規範各產業二氧化碳排放水準,若各產業節能技術或政府相關配套政策未改善,倉促實施碳排放管制,除了對管制對象的產生影響外,也可能間接衝擊未管制對象。政府除了加強輔導各種產業從事節能技術外,也需要適當的公布各產業各公司的各種汙染排放量資訊,以供各界研究碳排放管制或其他汙染排放管制對社會的影響。 / Global warming has become the topic of most countries which concerns things in recent years. Government sets up CO2 reduction objectives and principle in “General National Plan for Energy Saving and Carbon Reduction” in 2010, but the plan doesn’t probe effect of CO2 regulation which different industries. Therefore, it is unknown that different industries should be responsible for the abatement of CO2. In order to clearly understand effect of CO2 regulation for Taiwan industrial sector, this paper use directional distance function to estimate production efficiency and pollution abatement cost of 367 public companies in 14 industries in industrial sector from 2005 to 2010, and to reflect different industries’ opportunity cost under CO2 regulation. Production efficiency of different industries after the implementation of CO2 regulation will be higher than before the implementation of CO2 regulation. On the other hand, different industries have a variety of average pollution abatement cost and pollution abatement cost of CO2 per ton. However, Taiwan has not yet adopted the environment laws to set up industrial CO2 emission level, if the government hurriedly implemented CO2 regulation for Taiwan industrial sector, may be indirectly influence other sectors. Hence, the government should not only urge that industries must be engaged in energy-saving technologies, but also announce companies’ various pollution emission information which provides research institutes to analyze effect of social welfare under CO2 regulation.

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