Thèses : « Analysis of conversations (AC) »

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VERGINE, ILARIA. « (Inter)azioni Comunicative e Identità in Ambienti di Realtà Mista : Una Proposta Metodologica ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2021. http://hdl.handle.net/10280/107360.

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L’avanzamento delle tecnologie digitali ha permesso ai soggetti di interagire in ambienti diversi da quelli fisici causando cambiamenti nelle modalità di comunicazione. Il dispositivo Microsoft HoloLens (MHL) ha introdotto la possibilità di sperimentare un nuovo ambiente chiamato pure mixed reality. Questo lavoro consiste in una proposta metodologica interdisciplinare per studiare la comunicazione sincrona e il farsi dell’identità in essa quando viene utilizzato MHL. Per rispettare la complessità ontologica del fenomeno, ho combinato due prospettive: multimodality e social psychology of cyberplaces. L’adozione di queste prospettive ha permesso di ritagliare all’interno del fenomeno studiato un oggetto di ricerca definibile come (inter)azione comunicativa. Per studiarlo, ho elaborato una proposta metodologica che combina due metodi qualitativi: multimodal (inter)action analysis (MIA; dalla multimodality) e analysis of conversations (AC; dalla social psychology of cyberplaces). Per esaminare il farsi dell’identità nell’(inter)azione comunicativa, ho arricchito la proposta metodologica con l’intersubjectivity model, una proposta di modello teorico derivato da: MIA identity framework dalla multimodality e modello dell’intersoggettività enunciativa dalla social psychology of cyberplaces. L’intera linea argomentativa del lavoro è stata supportata da esempi di analisi utilizzando un corpus di 16 (inter)azioni comunicative diadiche videoregistrate. Ogni diade era composta da un soggetto che utilizzava MHL e uno che utilizzava un pc.
Advances in digital-based technologies have allowed subjects to interact in environments other than physical ones causing changes in communication modalities. Microsoft HoloLens (MHL) introduced the possibility of experiencing a new digital environment: pure mixed reality. This work consists of an interdisciplinary methodological proposal to study synchronous communication and the making of identity in it when MHL is used. To respect the phenomenon’s ontological complexity, I combined two perspectives in this work: multimodality and social psychology of cyberplaces. The adoption of these perspectives reduced the phenomenon in a research object called communicative (inter)action. To study it, I elaborated a methodological proposal that combines two qualitative methods: multimodal (inter)action analysis (MIA; from multimodality) and analysis of conversations (AC; from social psychology of cyberplaces). To examine the making of identity in communicative (inter)action, I enriched the methodological proposal with a theoretical model proposal. The theoretical model proposal is a model that I called intersubjectivity model derived from: MIA framework on multimodal identity from multimodality and utterance intersubjectivity model from social psychology of cyberplaces. The line of argument was supported by analysis examples using a corpus of 16 videotaped dyadic communicative (inter)actions. Each dyad had one subject using MHL and another using a pc.

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Santos, Muñoz Arantxa. « Conversación digital : copresencia y disponibilidad : Estudio pragmático del preámbulo de reuniones multipartitas por videoconferencia ». Doctoral thesis, Uppsala universitet, Romanska språk, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:du-23172.

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The present thesis explores how interaction is initiated in multi-party meetings in Adobe Connect, 7.0, with a particular focus on how co-presence and mutual availability are established through the preambles of 18 meetings held in Spanish without a moderator. Taking Conversation Analysis (CA) as a methodological point of departure, this thesis comprises four different studies, each of them analyzing a particular phenomenon within the interaction of the preambles in a multimodal environment that allows simultaneous interaction through video, voice and text-chat. The first study (Artículo I) shows how participants solve jointly the issue of availability in a technological environment where being online is not necessarily understood as being available for communicating. The second study (Artículo II) focuses on the beginning of the audiovisual interaction; in particular on how participants check the right functioning of the audiovisual mode. The third study (Artículo III) explores silences within the interaction of the preamble. It shows that the length of gaps and lapses become a significant aspect the preambles and how they are connected to the issue of availability. Finally, the four study introduces the notion of modal alignment, an interactional phenomenon that systematically appears in the beginnings of the encounters, which seems to be used and understood as a strategy for the establishment of mutual availability and negotiation of the participation framework. As a whole, this research shows how participants, in order to establish mutual co-presence and availability, adapt to a particular technology in terms of participation management, deploying strategies and conveying successive actions which, as it is the case of the activation of their respective webcams, seem to be understood as predictable within the intricate process of establishing mutual availability before the meeting starts.

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Joty, Shafiq Rayhan. « Discourse analysis of asynchronous conversations ». Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45674.

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A well-written text is not merely a sequence of independent and isolated sentences, but instead a sequence of structured and related sentences. It addresses a particular topic, often covering multiple subtopics, and is organized in a coherent way that enables the reader to process the information. Discourse analysis seeks to uncover such underlying structures, which can support many applications including text summarization and information extraction. This thesis focuses on building novel computational models of different discourse analysis tasks in asynchronous conversations; i.e., conversations where participants communicate with each other at different times (e.g., emails, blogs). Effective processing of these conversations can be of great strategic value for both organizations and individuals. We propose novel computational models for topic segmentation and labeling, rhetorical parsing and dialog act recognition in asynchronous conversation. Our approaches rely on two related computational methodologies: graph theory and probabilistic graphical models. The topic segmentation and labeling models find the high-level discourse structure; i.e., the global topical structure of an asynchronous conversation. Our graph-based approach extends state-of-the-art methods by integrating a fine-grained conversational structure with other conversational features. On the other hand, the rhetorical parser captures the coherence structure, a finer discourse structure, by identifying coherence relations between the discourse units within each comment of the conversation. Our parser applies an optimal parsing algorithm to probabilities inferred from a discriminative graphical model which allows us to represent the structure and the label of a discourse tree constituent jointly, and to capture the sequential and hierarchical dependencies between the constituents. Finally, the dialog act model allows us to uncover the underlying dialog structure of the conversation. We present unsupervised probabilistic graphical models that capture the sequential dependencies between the acts, and show how these models can be trained more effectively based on the fine-grained conversational structure. Together, these structures provide a deep understanding of an asynchronous conversation that can be exploited in the above-mentioned applications. For each discourse processing task, we evaluate our approach on different datasets, and show that our models consistently outperform the state-of-the-art by a wide margin. Often our results are highly correlated with human annotations.

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Yang, Bo. « "Getting to know you" conversations ». Thesis, University of Aberdeen, 2013. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=210226.

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This dissertation is about “getting to know you” conversation, a form of conversation prevalent in everyday interactions. It has been defined (Garner 2004: 181) as an interaction in which participants, usually of equal social status, make initial contact and establish friendly relations, and in which they are largely concerned with finding neutral topics through which they can establish common ground—shared experiences, opinions, interests, and the like. This doctoral research was based on extensive recordings and transcription of such conversations in English between university students (both native with native and native with non-native speakers), in a relatively naturalistic setting. The analysis was conducted in two steps. The first step was to identify and describe the recurrent patterns of the data, through well-established methods of Conversation Analysis. The second was to classify identified structures within a pragmatic framework: in other words, to label utterances and sequences according to their functional properties, and to specify their roles in building relationships between the interactants. Three major sequences were identified and discussed in detail in terms of their forms, functions and distributions in a “getting to know you” conversation. Differences in usage and pragmatic effectiveness between native and non-native speakers were also identified. The research makes a new contribution to the relatively small but growing body of work in the field of conversational pragmatics. The findings of this PhD work can, and it is hoped will be, made available for EFL classroom use in China. Drawing on the present study, a potential model is proposed for an instructional unit on sequences in GTKY conversations. The suggested approach would result in a change to the typical roles of teacher and textbooks currently occurring in Chinese education, which is outlined at the end of this dissertation.

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Leung, Ka-yan, et 梁家欣. « Topic management in Cantonese conversations ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B31602939.

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Miles, Susie. « Creating conversations : an inclusive approach to the networking of knowledge about education in Southern contexts ». Thesis, University of Manchester, 2009. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:194503.

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This thesis provides a synthesis of knowledge about inclusive networking in an international context, derived from the experience of stakeholders in education in countries of the South. It is suggested that inclusive networking facilitates the telling of stories, challenges stereotypes, humanises headlines and promotes contextually relevant research. The research question: “What are the key principles for the development of an inclusive international network?” was developed as a guide to this study. Using a process of autoethnographic analysis, I identified my tacit knowledge of inclusive networking through a continual analysis and cross-referencing of the ten publications presented here, and a wider search of the literature. This thesis is presented as a narrative in three parts. In the first part I trace my motivation for becoming involved in international networking as a strategy to address global inequality, review the literature on networking most relevant to this thesis, and identify some of the barriers to publishing faced by education stakeholders in the South. In the second part, a case study of the Enabling Education Network (EENET) is presented and a wide range of networking dilemmas identified, related to the way information is collected and shared across diverse Southern contexts. The overarching dilemmas of northern dominance and deficit thinking are discussed in the context of oral culture and the global digital and communication divide, and the difficulties in promoting genuinely critical conversations. In the third part, it is argued that contextual detail and transparency about authorship are critical to the construction of stories and accounts if they are to be meaningfully networked across diverse contexts. However, it is suggested that investing resources in the development of documentation, reflection and analytical skills in education stakeholders is an essential part of inclusive networking, if ‘promising’ practice is to be captured from a Southern perspective. Following this, the penultimate chapter puts forward four key principles relating to the development of an inclusive international network that emerged from the analysis of publications and the wider literature: 1. sharing of information, knowledge and stories between contexts; 2. knowledge creation: through reflection, documentation and analysis; 3. balancing insider and outsider knowledge and perspectives; and 4. developing appropriate responses at community level. I conclude with some possible future directions for research, and with a personal story which encapsulates the theoretical framework of this thesis.

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Klitsie, Clara. « Teacher conversations : what happens when teachers talk ». Thesis, Nelson Mandela Metropolitan University, 2014. http://hdl.handle.net/10948/d1020081.

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Teaching has a primary focus on engagement with students, but paradoxically, it can be experienced as lonely, private work, in classrooms behind closed doors, with an accompanying sense of deep disconnection from peers. When six experienced teachers sought to counteract this isolation, they formed a group which embarked on a shared journey of reflection and conversation, with the purpose of increasing selfknowledge, clarifying a sense of self as teacher, extending understanding of the selfhood of other teachers, and exposing the deeper sources of meaning underlying the vocation of teacher. This study sought to describe the information, opinions and beliefs which were exchanged among participants within the group and to describe the dynamics within the group. Furthermore, it sought to identify and describe the self-perceived impact of the experience of such a group, on the vocational vitality of each of the participants. Within an interpretivist epistemology a qualitative phenomenological research approach was adopted for the study. Data were obtained from two sources, consisting of transcripts of conversations from the meetings of a collaborative reflective group and from semi-structured individual interviews with group participants. These were analysed using an inductive approach with the aid of qualitative data analysis software: Atlas ti®. Findings from the study show that a high level of trust and a sense of safety were created through the use of guiding principles for meetings. Content chosen for reflective conversations and the general experience of meetings was perceived as providing a rare opportunity for participants to discover their selfhood as teachers. They reported that this understanding was further broadened by exposure to the selfhood of other teachers. Furthermore, members of the talk group reported that participation had resulted in a lowering of their sense of professional isolation and a renewal of vitality in their teaching. It is hoped that the findings from the study will inform an understanding of the experience of dialogue in a reflective, peer group where teachers focus on exploring together “who they are” as teachers. It provides valuable insights of the personal and professional transformations which can take place for teachers participating in conversations which focus on their inner landscape. Furthermore, the study has the potential to inform South African teacher professional development programmes with approaches which focus on teacher vocational renewal and vitality.

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Kwak, Sangshin. « Design and analysis of modern three-phase AC/AC power converters for AC drives and utility interface ». Texas A&M University, 2005. http://hdl.handle.net/1969.1/2336.

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Significant advances in modern ac/ac power converter technologies and demands of industries have reached beyond standard ac/ac power converters with voltage-source inverters fed from diode rectifiers. Power electronics converters have been matured to stages toward compact realization, increased high-power handling capability, and improving utility interface. Modern ac/ac power converter topologies with various control strategies have been introduced for the further improvements, such as matrix converters, current-fed converters, PWM rectifiers, and active power filters. In this dissertation, several new converter topologies are proposed in conjunction with developed control schemes based on the modern ac/ac converters which enhance performance and solve the drawbacks of conventional converters. In this study, a new fault-tolerant PWM strategy is first proposed for matrix converters. The added fault-tolerant scheme would strengthen the matrix converter technology for aerospace and military applications. A modulation strategy is developed to reshape output currents for continuous operation, against fault occurrence in matrix converter drives. This study designs a hybrid, high-performance ac/ac power converter for high power applications, based on a high-power load commutated inverter and a mediumpower voltage source inverter. Natural commutation of the load commutated inverter is actively controlled by the voltage source inverter. In addition, the developed hybrid system ensures sinusoidal output current/voltage waveforms and fast dynamic response in high power areas. A new topology and control scheme for a six-step current source inverter is proposed. The proposed topology utilizes a small voltage source inverter, to turn off main thyristor switches, transfer reactive load energy, and limit peak voltages across loads. The proposed topology maximizes benefits of the constituent converters: highpower handling capability of large thyristor-based current source inverters as well as fast and easy control of small voltage source inverters. This study analyzes, compares, and evaluates two topologies for unity power factor and multiple ac/ac power conversions. Theoretical analyses and comparisons of the two topologies, grounded on mathematical approaches, are presented from the standpoint of converter kVA ratings, dc-link voltage requirements, switch ratings, semiconductor losses, and reactive component sizes. Analysis, simulation, and experimental results are detailed for each proposed topology.

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Shvets, Dmitry. « Analysis of AC low-voltage energy harvesting ». Thesis, Monterey, California. Naval Postgraduate School, 2014. http://hdl.handle.net/10945/43719.

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Approved for public release; distribution is unlimited
Piezoelectricity is a material property that generates an electric charge proportional to the mechanical stress placed on the material. This phenomenon was first discovered by the Curie brothers in 1880. This material property gives the ability to turn vibrations into an electrical waveform, but power electronics is necessary to harness this low-level energy. AC power is often produced at the power plant level in modern society; however, low voltage AC power is widely available in vibrational form. The U.S. Navy may be able to utilize piezoelectric technology to harness wasted vibrational energy. Some of these applications include inserting a piezoelectric harvester in shoes to supply small amounts of power to cell phones or utilizing motion energy to provide power to iPod chargers. The power electronics that provides full bridge rectification and step down conversion, which achieves AC-DC power harvesting, is discussed. Also discussed is a breakdown of possible applications for such a device as well as the benefits of turning AC power into DC. A Linear Technology LTC-3588-1 integrated circuit was simulated in software and demonstrated in hardware. The hardware experiment showed that the software accurately predicted the performance of the chip.

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Bergstedt, Edwin, Johan Földhazy et Alexander Lundstjälk. « Vibration Analysis on AC Electric Arc Furnace ». Thesis, KTH, Materialvetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-173354.

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A computerized Fast Fourier Transform system has been used to analyse vibration measurements sampled from a 100-ton electric arc furnace. It has been the hypothesis that patterns in the vibration data would correlate to specific events in the electric arc furnace during the melting process. The theory was that the vibration patterns would be most powerful in multiples of 50 Hz, as the electric arcs operate with a frequency of 50 Hz. It was concluded that the multiples of 50 Hz were dominant. Investigation was made regarding how the amount of scrap affects the amplitude in the vibrations after a defined amount of energy input. It was confirmed that the intensity of the vibrations decreased with increasing mass and basket volume. Another discovery was the M-shaped pattern at the beginning of the melting process. This pattern was statistically analysed. It was found that 71 % of the 41 charges showed an M-shaped correlation. The appearance of this M-shape was analysed regarding power usage, and steel-type. It was concluded that the steel type affected the appearance of the M-shape. The occurrence of flat-bath was also investigated. The theory was that the vibration data would be fairly constant with the occurrence of flat-bath. It was discovered that the vibration data experienced a somewhat constant behaviour towards the end of the melting process in approximately 57 % of the 41 charges. Difficulties were encountered regarding detection of patterns, and correlating them to specific conditions, due to the many parameters that affect the vibration measurements from charge to charge. It was concluded that vibration analysis are unlikely to be used as an absolute way to foresee every event in the electric arc furnace during each charge. But can rather serve as a statistical tool, upon which decisions of how the melting process should be conducted could be based on.

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Morganti, Diego. « AC electrokinetic analysis of chemically modified microparticles ». Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/341415/.

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Electrokinetic manipulation offers a flexible and versatile tool to analyse and precisely handle microparticles, it is non invasive and can be easily implemented in microfluidic devices. Those characteristics make the electrokinetic methods appealing in the field of medical diagnostics because of their ability to perform analysis on a single particle basis, for example to detect binding events of biomolecules such as antibodies and nucleic acids. The detection is performed without fluorescent tags or chemical modifications, because it uses the electrical properties of the surface of the particles as label. The aim of this project is to study the electrical properties of microparticles according to the chemical properties of their surface using electrokinetic on a single particle basis. A new method to analyse single particles that relies on electrorotation and electroorientation has been introduced. Using quadrupolar electrodes it has been possible to obtain both spectra for the same particle allowing a combined fitting of the data. Rod shaped particles have been analysed after each step of the biochemical modifications needed to obtain a surface functionalised with antibodies. We found that the chemical modifications happen mostly in the bulk of the particles, therefore not many charges were available onto the surface. Anyway, it has been possible to distinguish different types of particles using the surface conductance of the particles and their permittivity. Along with biochemically modified particles, also metal coated particles have been analysed to study the electrical double layer under different conditions, like different suspending medium conductivities and surface functionalisations. Particles of different shapes were metal coated with gold after a suitable chemical modification to sensitize their surface. The gold coating is an autocatalytic electroless process; therefore it has been used to plate particles in suspension without the need of an external current source. Metal coated particles’ behaviour is dominated by the double layer at low frequency, but the results are only in qualitative accord with the theory due to the roughness of the metal surface.

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Van, Schalkwyk Christine. « Analysis and design of a voltage regulator based on an AC-to-AC converter ». Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53254.

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Thesis (MScEng)--University of Stellenbosch, 2003.
ENGLISH ABSTRACT: This thesis discusses the analysis and design of a voltage regulator based on an AC-to-AC converter. A background study was performed on the best topology for the purpose. The chosen topology was analysed and the converter was designed in detail. A voltage sign-detector and an over-current detector were designed and built. They were used for control and protection. Three methods of control were investigated. The first was a slow but reliable method of computing the RMS value of the input voltage and then using that value and the RMS value of the desired output voltage to compute the duty ratio of the converter. The second method was fast and is an open-loop control method, where the measured input voltage and a reference value of the desired output voltage are used to compute the duty ratio. The third method is a closed-loop control method in which the input voltage, output voltage and the same reference values used in the second method are used to compute the duty ratio. All of these methods were implemented and tested.
AFRIKAANSE OPSOMMING: Hierdie tesis bespreek die analise en die ontwerp van 'n spannings reguleerder wat gebaseer is op 'n WS-na-WS omsetter. 'n Ondersoek was ingestelom die beste topologie te vind vir die doel. Die topologie wat gekies is, is toe geanaliseer en die omsetter is in detailontwerp. 'n Spannings-tekendetektor baan as ook 'n oorstroombeskermings baan was ontwerp en is gebou. Hierdie bane word gebruik vir die beheer en die beveiliging van die stelsel. Daar is drie metodes van beheer wat ondersoek is. Die eerste metode is stadig, maar betroubaar. Die metode bereken die WGK waarde van die intree spanning en gebruik dan die waarde en die WGK van die gewenste uittree spanning om die diens siklus van die omsetter uit te werk. Die tweede metode van beheer is vinnig en is 'n oop-lus metode van beheer. Hierdie metode maak gebruik van die gemete intreespanning en 'n verwysing van die gewensde uittree spanning om die dienssiklus uit te werk. Die derde metode is 'n geslote-lus beheer wat van die gamete intreespanning, die gemete uittreespanning en die verwysing soos die in die tweede beheermetode gebruik maak on die diens siklus uit te werk. AI die metodes was geimplementeer en getoets.

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Twitchell, Douglas P. « Automated Analysis Techniques for Online Conversations with Application in Deception Detection ». Diss., Tucson, Arizona : University of Arizona, 2005. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu%5Fetd%5F1111%5F1%5Fm.pdf&type=application/pdf.

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Takeda, Tomoko. « Interaction between interlocutor relationship and grammar in Japanese conversations / ». view abstract or download file of text, 2006. http://proquest.umi.com/pqdweb?did=1196393791&sid=1&Fmt=2&clientId=11238&RQT=309&VName=PQD.

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Thesis (Ph. D.)--University of Oregon, 2006.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 129-137). Also available for download via the World Wide Web; free to University of Oregon users.

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Alexandros, Kordonis. « DYNAMIC ANALYSIS AND MODELING OF AC/AC POWER CONVERTERS FOR APPLICATIONS TO SMART-GRID SOLUTIONS ». 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/199313.

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Keller, Jill Leslie. « Conversational implicature and higher-order thinking in instructional conversations ». Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185982.

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Results from curriculum enactment and sociolinguistic research have indicated that lessons are composed of information exchanges consisting of mostly facts and procedures that place little cognitive demand on students. Scholars from these areas have ascribed the characteristics of the school, teacher, student, management and task demands, or linguistic, and/or social context as explanations for those observations. They have not made a direct connection between how teachers and students decide who takes responsibility for providing the intellectual content of lessons and how that decision affects the students' higher order contributions. Consequently, the present study was designed to examine the way teachers and students cooperated for effective information exchanges and how that cooperative effort influenced students' higher order contributions. One hundred twelve chemistry and mathematics tutorials formed the data. The volunteer tutors possessed extensive training in their subject areas and the problems for discussion were designed to make high cognitive demands on the volunteer students. Methods from discourse analysis were used to develop an analytical model to identify, describe, and compare how the tutors and students exchanged information. The model was applied to the data to provide information on the following topics; the roles of the tutor and student, the substance of the exchanges, and the use of mediation strategies. Next, a code of conduct known as Grice's (1975) theory of conversational implicature was used to interpret the results of the analysis. The aim was to link conversational cooperation with students' higher order contributions to the discourse. First, the results indicated a model can be developed to describe, compare, and categorize instructional conversations. Second, tutors and students cooperate to maintain their roles during instruction and mediation strategies support those roles. Third, tutors and students intuitively follow Grice's (1975) conversational code of conduct to support their roles during their information exchanges. This cooperative effort is rooted in the conditions for conversational implicature. It was found when teachers and students explicitly negotiate and accept new intellectual roles before instruction (the conditions for implicature), higher order thinking can be encouraged by teachers and contributed by students to instructional conversations.

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Yamaji, Harumi. « Manipulation of Honorifics in First-Encounter Conversations in Japanese ». Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195228.

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This study quantitatively and qualitatively examines honorific usage in casual first-encounter conversations between two relatively young people from similar backgrounds. The issues of concern are the frequency of use of addressee and referent honorifics, different types and forms of referent honorifics, reasons behind speech style shifts between honorific and non-honorific forms, and gender differences in honorific usage.Overall, addressee honorifics were predominantly used compared to plain forms, while the use of referent honorifics was limited in the data. The rate of honorific usage ranged greatly depending on the speaker and the conversation. Using too few addressee honorifics, however, has a possibility of offending the addressee in this speech context.Additionally, it was found that female speakers did not necessarily speak more politely (i.e., use more honorifics) than male speakers. The addressee's gender seemed to influence the rate of use of honorifics. Female speakers' use of addressee honorifics was higher in mixed-sex conversations than in single-sex conversations while the opposite was true with male speakers. As for referent honorifics, both genders tended to use more of them in single-sex conversations.As for speech style shifts between honorific forms and non-honorific forms, several contexts in which these were observed are reported. Self-directed questions and expression of feelings, thoughts, and opinions were the two most likely contexts for speech style shifts between addressee honorifics and plain forms. It appears that such style shifts occur to separate the utterances from the main course of conversation to signal that the utterance is not deliberately addressed to the addressee, that the focus is on meaning, or that the utterance constitutes a subspace embedded in the main floor rather than the main floor itself. Additionally, utterance type, increased familiarity with the addressee, speech style adjustment, and the introduction of new topics are suggested as possible contexts for speech style shifts between referent honorifics and non-honorific forms.

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Mallett, Jane. « Nurse-patient haemodialysis sessions : orchestrated institutional communication and mundane conversations ». Thesis, Open University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364120.

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Arrowsmith, Dinah Rachel. « An analysis of conversations between children and teachers in nursery counting activities ». Thesis, University of Leeds, 2005. http://etheses.whiterose.ac.uk/805/.

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Learning to count is a central strand to the mathematical development area of the Foundation Stage Curriculum in England and Wales. Five teachers from five nurseries in one local education authority within West Yorkshire were recorded between December 2002 and June 2003. The main data for the study was taken from 21 number focus activities recorded between the teachers and small groups of children, aged 3-4 years. Conversation Analysis was used to determine the language and interaction involved, considering both children and teachers' contributions to counts and to what came before and after counts. The study found that the teachers were responsible for creating the conversational contexts for counting as well as being involved in the counting itself. The collaboration between teachers and children in counts included distinctive uses of intonation in ways that emphasised the status of numbers in the count sequence and the importance of the last word. Following counts, the study identified ways in which the quantitative meaning of counting could be extended or left implicit. This study depicts counting as a fully interactive activity that contrasts with the image portrayed in much of previous literature where children count independently and opportunities for teachers' participation are under-specified and implicitly passive.

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Čermák, Jan. « Finanční analýza AC Sparta Praha ». Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-72261.

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This diploma work deals with problems of financial analysis which is an important and indispensable instrument for managing of modern company. For this company was chosen AC Sparta Praha fotbal, a.s. In theoretical part of this bachelor work, there are determined and described basic importace of financial analysis, users of financial analysis, information sources for financial analysis, needs and techniques and methods of financial analysis. It also consists of description of corporate environment, which is very specific in this case.Practical part takes use of these theoretical knowledge to realize financial analysis of AC Sparta Praha fotbal, a.s., whereas the main importace was put on processing of analysis of chosen ratio indicators, cost and revenue analysis and the SWOT analysis. Conclusion contains results evaluation from practical part and suggestions and recommendation for financial recovery.

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Grancea, Erica Liana. « Aspects of sequence and preference organization in Romanian telephone conversations ». Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1693061471&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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Petrarca, Ivan. « Unified analysis and operating point calculation of AC drives ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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Sommario La seguente tesi si basa sulla modellizzazione di un generico motore elettrico trifase, nel corso della trattazione è stata svolta un’analisi unificata di questo problema in modo da poter includere nel modello motori asincroni e brushless anche molto diversi tra loro semplicemente cambiando i parametri iniziali. Considerato un veicolo elettrico, quando si agisce sul pedale dell’ acceleratore viene generato un riferimento di coppia per soddisfare le richieste del guidatore, in genere la coppia di riferimento viene soddisfatta per mezzo di regolatori PI, tuttavia questo modello può andare a compensare i ritardi o le oscillazioni dei regolatori e ipoteticamente migliorare il comportamento del sistema. Il modello in questione ha diversi ingressi, i principali sono il numero di giri del motore e la coppia di riferimento, a questo punto esso è in grado di fornire in modo analitico la corrente necessaria a soddisfare quella coppia e la coppia effettivamente erogata nel punto di lavoro calcolato. Per il calcolo del punto di lavoro vengono utilizzati degli algoritmi basati sul metodo di Ferrari per la risoluzione delle quartiche; infatti man mano che il numero di giri aumenta bisogna spostarsi lungo diverse curve i cui punti sono soluzioni di equazioni di quarto grado. Per ogni istante quindi il modello calcola le soluzioni di queste equazioni e in seguito sceglie il punto di lavoro ottimale rispettando i limiti di corrente e di velocità; anche se si utilizza un altro tipo di motore non cambia il metodo di risoluzione delle quartiche, cambia però il sistema di scelta del punto di lavoro ottimale perché per ogni motore variano le curve che lo caratterizzano.

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Menberu, Beniyam. « Analysis of hot-carrier AC lifetime model for MOSFET ». Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/39386.

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Puchalska, Sylvia. « The mother and the child clinical psychologist : a discursive analysis of professional conversations ». Thesis, University of Hertfordshire, 2012. http://hdl.handle.net/2299/7761.

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Aim: Motherhood is placed under a lens by society: mothers are expected to fit within narrowly defined characteristics which dictate who mothers should be and how they should act. Although there are numbers of articles that explore this issue, little attention has been paid to how health professionals, and clinical psychologists in particular, position themselves in relation to societal ideas about motherhood. The research aims to define the discursive resources used by Clinical Psychologists (CPs) to construct the shapes and identities of motherhood, and to explore how these resources were deployed. Method: A discourse analysis approach is employed. Data came from 3 focus group interviews (N=9), which were set up in order to explore motherhood and mothers. Participants were all qualified CPs working within Child and Adolescent Mental Health Services (CAMHS) in the UK. The research is positioned within a social constructionist frame and takes a critical realist position. The analysis includes elements of both discursive psychology and critical discourse analysis, filtered through a postmodern feminist lens. Findings: A number of discursive practices and identity positions around womanhood and motherhood were highlighted and a set of interlinked dilemmas emerged for women around how to be a woman and how to be a mother. A further dilemma emerged for CPs which encompassed how they worked with women, and what positions they took when doing so. Womanhood and motherhood appeared to be troubled, which had the potential to oppress mothers attending CAMHS. Female CPs were included within this trouble, however, which created interesting juxtapositions within the deployment of discursive resources. Finally, some positive discursive practices were identified which highlighted acceptance and tolerance of pluralities of being a woman and being a mother. Implications: Reflection, deconstruction and an opening up of the debate were seen to be useful devices in helping psychologists to expose potentially oppressive practices. Politicisation of psychology was also explored.

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Gulick, Eleanor. « Developing discourse structure analysis for use on conversations that include people with aphasia ». Bowling Green State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1594159643173734.

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Salmon, Joseph L. « A Case Study of Grade-Level Meetings and Coaching Conversations ». Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77112.

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The goal of this research project was to determine the content of the discourse occurring in grade-level meetings and coaching sessions and participants' perceptions of how the conversations in these two venues impacted learning and practice for individual teachers. Learning Forward's Standard for Professional Learning (2001) recommended that teachers organize into learning communities providing continuous learning opportunities to enhance adult learning and collaboration. Little (2003a) found that research was lacking that described the dynamics of communities of practice that promote teacher learning. It was in the content of the discourse that a proxy for evidence was found that the actions of the instructional coaches and grade-level meetings impact teacher growth. A case study was utilized to examine these structures and processes for job-embedded professional development at a school located in the eastern United States. Research questions focused on the nature of the discourse among teachers and coaches in the grade-level meetings and in individual coaching conversations. Teachers reported what they felt that they learned in the grade-level meetings and the coaching discussions. Additionally, teachers stated what they did differently as a result of this method of professional learning occurring in grade-level meetings and coaching discussions. Finally, the school's improvement plans were compared with the conversations in the grade-level meetings and coaching sessions. Verbatim transcriptions of recordings of grade-level meetings and coaching sessions provided data which revealed categories of content, coaching roles, and patterns of discourse. The goals of the meetings and coaching were to ensure communication about school district policies and to set expectations for teacher performance and student learning. Assertions generated provided patterns of discourse that identified roles of the principal, coaches, and teachers. This investigation utilized a descriptive content discourse analysis and found support for the finding that the actions of this emerging community of practice were directed by federal, state, and local polices for teacher performance and student learning. Patterns of discourse revealed roles of administration, coaches, and teachers as they collaborated to negotiate meaning through the building of a shared repertoire. Interview data revealed that these dynamics enhanced teacher growth in many cases; however, lack of teacher input may have limited some potential opportunities.
Ed. D.

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ae, hlim@pi ac, et Hwee Ling Lim. « Constructing Learning Conversations : A Study of the Discourse and Learner Experiences of Online Synchronous Discussions ». Murdoch University, 2006. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20070422.203120.

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The aim of this qualitative case study is to gain greater insight into the impact of online synchronous (chat) interaction on the learning process from a sociocultural constructivist perspective in the context of an online undergraduate unit. Given the sparse research on the effectiveness of chat interaction in supporting knowledge construction processes, few appropriate analytical methods available for examining educational chat discourse, together with the pedagogical imperative to determine the extent to which the real-time computer-mediated communication (CMC) mode satisfies student learning needs, this study fills the gaps in current research by examining the impact of chat interaction in facilitating participation, knowledge construction, and quality of online learning experience of two different online tutorial groups. Although the literature largely regards chat interaction as fragmented and characterized by interactional incoherence that disrupts the dialogic knowledge construction process, findings from this single-embedded case study of tutorial groups 1 and 4 (G1 and G4), involved in weekly critical discussions on set-readings over 11 weeks (one semester), show that chat interaction is more structured and complex than the literature suggests. This study utilizes a new methodological design that integrates discourse and social network analytical methods which are triangulated with self-reports of learning experiences from an online survey instrument. The application of a refined Exchange Structure Analysis coding instrument (Kneser, Pilkington, & Treasure-Jones, 2001) with social network analysis (Wasserman & Faust, 1994; Scott, 2000) to transcripts of chat interaction shows educational chat discourse to be coherent; reflecting the typical structure of pedagogical classroom exchanges. Findings from this study further establish that chat interaction enables participation opportunities in tutorial discussions which are valued as important, with variations in levels of participation within and between groups suggesting a pattern of active and peripheral participation which is not necessarily detrimental to learning. Chat interaction is also found to facilitate collaborative sharing of individual understandings and critical negotiation of meaning which are characteristic of the knowledge construction process, in the form of information-sharing and topic development phases in the exchanges of both groups. Although it is beyond the scope of this study to determine the exact form of knowledge constructed, individual and mutual appropriations of shared knowledge through chat interaction are reported by both groups. A between group comparison of available tutor scaffolding reveals consistently weak G1 tutor presence compared to strong G4 tutor support at the initial learning stages with gradual withdrawal of scaffolding over time. These results suggest differences in quality of online educational experiences which are confirmed by findings that compared to G1, G4 reported greater satisfaction with more chat tutorial factors; indicating an overall more positive, higher quality of experience with collaborative learning and group work processes afforded by the chat interaction. With its methodological design, instruments, and findings, this study contributes to existing knowledge on online interaction, advances on previous studies regarding impact of chat interaction on learning, and offers directions for future work in the fields of educational technology, linguistics, and group dynamics in educational social networks. When extrapolated to comparable cases, findings from this study could guide the pedagogical design of collaborative-constructivist learning activities that takes into account the role of chat interaction in the construction of learning conversations.

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Panìco, Daniela. « Bilingual conversations and language maintenance : The case of two Italian-Australian families ». Thesis, The University of Sydney, 2021. https://hdl.handle.net/2123/27490.

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This thesis explores bilingual practices within the everyday interactions of two Italian-Australian families living in Sydney. In these homes one parent is a speaker of Italian while the other parent is a speaker of English, with both English and Italian spoken daily to the children. The study is concerned with the ways in which language choices are deployed by parents and children in mundane family conversations and, especially, within practices aimed at maintaining Italian and bilingualism in the home. The investigation draws on data collected through audio and video recordings of family mealtimes and siblings’ playtime. It employs an approach in which Conversation Analysis is applied to the study of bilingual talk in order to explore the linguistic activities of participants and their language choices as negotiated on a moment-by-moment basis. Findings show that distinctive family language policies characterize the two homes, namely, a strict separation between the two languages in one family and a flexible use of the two languages in the other. In both families, the linguistic practices of the Italian-speaking parents are crucial in relation to the implementation of the use of Italian by the children in conversation. In particular, the detailed sequential analysis reveals that the Italian-speaking parents employ linguistic and other semiotic resources to enact discourse strategies which differently constrain the language choices of the children. In the first participant family, parental discourse strategies denoting consistency of choice of Italian and intensive use of response-eliciting formats, such as questions, are found as highly constraining on language choice. In the second family, the parental use of Italian in alternation with English and the selection of both response-eliciting and non-response-eliciting formats, such as declaratives, are found as low- or non-constraining on the language use of the children. Moreover, in the two families, the linguistic behaviour of the eldest siblings highly contributes either to support the use of Italian in the home or to shift conversations towards English. The findings point to family bilingual practices as collaboratively constructed and accomplished by participants and to everyday family talk as the locus of language maintenance or language shift. By focussing on the micro level of family interactions and on bilingualism as interactionally achieved, this study expands the line of research on family bilingualism and family language policy according to a conversation analytical perspective.

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Miller, Matthew James. « Talking into the profession : an analysis of problem-based conversations between elementary preservice teachers / ». Thesis, Connect to this title online ; UW restricted, 2005. http://hdl.handle.net/1773/7703.

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Pienaar, Kiran Merle. « A critical analysis of oppositional discourses of the ideal female body in women's conversations ». Thesis, Rhodes University, 2007. http://hdl.handle.net/10962/d1002641.

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Socialisation agents such as the popular media and same age female peers construct and reproduce notions of what is physically ideal, feminine and beautiful in a woman (Hesse-Biber 1996). My interest lies in how a group of young women reproduce, contest and possibly transform such notions in conversations with their same age female friends. The study aims to answer the following question: What ideologies are reflected and perpetuated in the discourses associated with the ideal female body? Since notions of what is ideal and beautiful are indeterminate and in perpetual flux, I focus in particular on areas of contradiction and contestation in the body talk conversations. As such, the analysis examines three extracts in which the young women draw on oppositional discourses to construct notions of female beauty. I believe that these extracts represent discursive struggles in relation to the dominant Western ideal of the slim, toned female body, an ideal which more closely resembles a newly pubescent girl's body than the curvaceous, shapely body of an adult woman (Bartky 2003; Grogan 1998). My analysis is based on conversational data collected from sixteen, white adolescent English-speaking women between the ages of fourteen and eighteen who attend a boarding school in Grahamstown. I elicited the body talk data using three stimulus exercises designed to encourage discussion on topics such as the overweight female body, dieting and the ideal body. I selected three extracts from the recorded conversations and used the methodological framework of Critical Discourse Analysis to analyse the data. This framework proposes three interdependent stages of analysis: 1) the Description of the formal features of the text, 2) the Interpretation of the text in terms of the participants' background assumptions, the situational context and the intertextual context and 3) an Explanation of the text in light of the sociocultural context and the text's contribution to the reproduction or transformation of the status quo. Since I was present during the conversational recordings and contributed to the discussions, part of the interpretation stage of analysis critically evaluates how the asymmetrical power relations between myself and the participants influenced the conversations. In this regard, my findings attest to my coercive role in promoting conservative, reactionary discourses which sustain the dominance of traditional ideologies of female beauty and which stifle oppositional ideologies. My interpretation of the extracts also reveals that, in their discussions of topics such as excess weight, female ageing and cosmetic surgery, the young women negotiate alternative conceptions of what constitutes the ideal female body. However, the articulation of an alternative beauty ideal, one which values women of different body sizes and ages is not sustained in the extracts. By discussing the relationship between these alternative constructions and dominant norms of beauty, I show how the prevailing ideal of the youthful, slim, toned female body wins out in the conversations. The interpretation of the extracts also reveals the participants' preoccupation with the pursuit of health and well¬being. In this respect, the young women construct the ideal body as not only slim and youthful, but also healthy. In my explanation of the extracts, I explore the sociocultural factors which have contributed to the rise of the health ethic. In concluding, I argue that the valorisation of the healthy body in the conversations, far from challenging the imperative to be thin, actually reinforces it by constructing dieting as a necessary adjunct to the pursuit of health. From this perspective, the preoccupation with attaining the ideal thin, toned body can be justified in terms of a desire to be healthy.

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Robbins, Megan L. « A Social Interaction Analysis of the Daily Conversations of Couples Coping with Breast Cancer ». Diss., The University of Arizona, 2012. http://hdl.handle.net/10150/222896.

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This dissertation used naturalistically-observed snippets of actual conversations of couples coping with breast cancer to understand how often, with whom, and how couples talk about cancer and other topics, and how these conversations relate to both partners' adjustment to the experience. Fifty-six breast cancer patients undergoing treatment and their spouses wore the Electronically Activated Recorder (EAR) for one weekend and completed adjustment questionnaires at baseline and a two-month follow-up. The first study revealed that couples discussed cancer in fewer than 10% of their conversations, and that these conversations occurred more frequently with each other than with friends and family. Cancer conversations tended to be informational and supportive, and spouses', rather than patients', discussion of cancer tended to be more related to adjustment. The second study analyzed the social language used within couples' cancer-related and other topics of conversation. Specifically, it examined the associations between we-talk (first-person plural pronouns), I-talk (first-person singular pronouns), and you-talk (second-person pronouns) and couples' adjustment. Results revealed that, contrary to prediction, both partners' we-talk was associated with concurrent, rather than future, adjustment. Further, both partners' focus on the spouse, indicated by I-talk and you-talk, was related to better adjustment for spouses. The findings in this dissertation indicate that psychosocial factors influence spouses' adjustment at least as much as patients' adjustment to breast cancer, and that couples without an exclusive focus on the patient may fare better overall.

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Ku, Jeong Yoon. « Korean honorifics : a case study analysis of Korean Speech levels in naturally occurring conversations ». Thesis, Canberra, ACT : The Australian National University, 2014. http://hdl.handle.net/1885/12376.

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The Korean honorific system, one of the significant grammatical systems in Korean, indicates the hierarchical social status of participants and plays an essential role in social interaction. For example, the speech levels are forms of sentence final suffixes attached to verbs and adjectives. They can be grammatically organized according to speakers' relationships. Speakers must choose among these verb endings and/or vocabulary items during every interaction. Therefore, the proper use of speech levels is a key factor in the expression of social identities, speakers' interpersonal feelings, and relationships. However, interpersonal feelings and relationships are hard to explain through actual use of speech levels. There are two aspects of interpersonal relationships between the participants in a conversation that affect the use of honorifics: vertical distance (gender, age) and horizontal distance (the degree of intimacy), and these two aspects of interpersonal relationships show the complexity of the use of speech levels. Because of the complexity of the use of speech levels, many Korean language learners feel that it is difficult to learn Korean speech levels. Several researchers have examined Korean language textbooks and language teaching in terms of Korean honorifics. They have pointed out several problems in current teaching materials and emphasized the importance of pragmatic factors and the necessity of authentic data to fully reflect actual Korean honorific uses. Addressing these issues, the thesis demonstrates the need for teaching materials that introduce how honorific speech levels are used in naturally occurring conversation by showing the complexity of how one speaker can use and switch among speech levels depending on the interlocutors or situations in the conversational interaction.

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Svátek, Jan. « Ekonomická analýza společnosti AC Sparta fotbal, a. s ». Master's thesis, Vysoká škola ekonomická v Praze, 2007. http://www.nusl.cz/ntk/nusl-10647.

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The goal of this diploma thesis is to analyze and evaluate situation of the corporation AC Sparta Praha fotbal, a.s. (AC Sparta Prague football). In the diploma thesis, there are applied generally used approaches and instruments for analysis of joint stock company. The situation of Sparta Prague is compared also with other clubs. I can see the biggest contribution of my work in a fact that till this time there is no analysis, which deals with czech football club in this comprehensive way.

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Pietiläinen, Kai. « Voltage sag ride-through of AC drives : control and analysis ». Doctoral thesis, KTH, School of Electrical Engineering (EES), 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-450.

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This thesis focuses on controller design and analysis for induction motor (IM) drives, flux control for electrically excited synchronous motors with damper windings (EESMs), and to enhance voltage sag ride-through ability and analysis for a wind turbine application with a full-power grid-connected active rectifier. The goal is to be able to use the existing equipment, without altering the hardware. Further, design and analysis of the stabilization of DC-link voltage oscillations for DC systems and inverter drives is studied, for example traction drives with voltage sags in focus.

The proposed IM controller is based on the field-weakening controller of Kim and Sul [31], which is further developed. Applying the proposed controller to voltage sag ride-through gives a cheap and simple ride-through system.

The EESM controller is based on setpoint adjustment for the field current controller. The analysis also concerns stability for the proposed flux controller.

The DC-link stabilization algorithm is designed following Mosskull [38], where a component is added to the current controller. The algorithm is further developed.

Analysis is the main focus, and concerns the impact of the different parameters involved. Proper parameter selection for the controller, switching frequency, and DC-link capacitor is given.

The impact of voltage sags is investigated for a power-grid-connected rectifier. Here, we analyze the impact of different types of voltage sags and phase-angle jumps. The analysis gives design rules for the DC-link capacitor and the switching frequency.

Experimental results and simulations verify the theoretical results.

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Qi, Li. « AC system stability analysis and assessment for Shipboard Power Systems ». Texas A&M University, 2004. http://hdl.handle.net/1969.1/3128.

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The electric power systems in U.S. Navy ships supply energy to sophisticated systems for weapons, communications, navigation and operation. The reliability and survivability of a Shipboard Power System (SPS) are critical to the mission of a Navy ship, especially under battle conditions. When a weapon hits the ship in the event of battle, it can cause severe damage to the electrical systems on the ship. Researchers in the Power System Automation Laboratory (PSAL) at Texas A&M University have developed methods for performing reconfiguration of SPS before or after a weapon hit to reduce the damage to SPS. Reconfiguration operations change the topology of an SPS. When a system is stressed, these topology changes and induced dynamics of equipment due to reconfiguration might cause voltage instability, such as progressive voltage decreases or voltage oscillations. SPS stability thus should be assessed to ensure the stable operation of a system during reconfiguration. In this dissertation, time frames of SPS dynamics are presented. Stability problems during SPS reconfiguration are classified as long-term stability problems. Since angle stability is strongly maintained in SPS, voltage stability is studied in this dissertation for SPS stability during reconfiguration. A test SPS computer model, whose simulation results were used for stability studies, is presented in this dissertation. The model used a new generalized methodology for modeling and simulating ungrounded stiffly grounded power systems. This dissertation presents two new indices, a static voltage stability index (SVSILji) and a dynamic voltage stability index (DVSI), for assessing the voltage stability in static and dynamic analysis. SVSILji assesses system stability by all lines in SPS. DVSI detects local bifurcations in SPS. SVSILji was found to be a better index in comparison with some indices in the literature for a study on a two-bus power system. Also, results of DVSI were similar to the results of conventional bifurcation analysis software when applied to a small power system. Using SVSILji and DVSI on the test SPS computer model, three of four factors affection voltage stability during SPS reconfiguration were verified. During reconfiguration, SVSILji and DVSI are used together to assess SPS stability.

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Pietiläinen, Kai. « Voltage sag ride-through of AC drives : control and analysis / ». Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-450.

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Fuerte, Esquivel Claudio Rubén. « Steady state modelling and analysis of flexible AC transmission systems ». Thesis, University of Glasgow, 1997. http://theses.gla.ac.uk/4616/.

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As electric utilities move into more competitive generation supply regimes, with limited scope to expand transmission facilities, the optimisation of existing transmission corridors for power transfer becomes of paramount importance. In this scenario, Flexible AC Transmission System (FACTS) technology, which aims at increasing system operation flexibility, appear as an attractive alternative. Many of the ideas upon which the foundations of FACTS rest were conceived some time ago. Nevertheless, FACTS as a single coherent integrated philosophy is a newly developed concept in electrical power systems which has received the backing of the major manufacturers of electrical equipment and utilities around the world. It is looking at ways of capitalising on the new developments taking place in the area of high-voltage and highcurrent power electronics in order to increase the control of the power flows in the high voltage side of the network during both steady state and transient conditions, so as to make the network electronically controllable. In order to examine the applicability and functional specifications of FACTS devices, it is necessary to develop accurate and flexible digital models of these controllers and to upgrade most of the software tools used by planners and operators of electric power systems. The aim of this work is to develop general steady-state models FACTS devices, suitable for the analysis of positive sequence power flows in, large-scale real life electric power systems.Generalised nodal admittance models are developed for the Advance Series Compensator (ASC), Phase Shifter (PS), Static Var Compensator (SVC), Load Tap Changer (LTC) and Unified Power Flow Controller (UPFC). In the case of the ASC, two models are presented, the Variable Series Compensator (VSC) and the Thyristor Controlled Series CapacitorFiring Angle (TCSC-F A). An alternative UPFC model based on the concept of Synchronous Voltage Source (SVS) is also developed. The Interphase Power Controller (IPC) is modelled by combining PSs and VSCs nodal admittance models. The combined solution of the power flow equations pertaining to the FACTS devices models and the power network is described in this thesis. The set of non-linear equations is solved through a Newton-Rapshon technique. In this unified iterative environment, the FACTS device state variables are adjusted automatically together with the nodal network state variables so as to satisfy a specified nodal voltage magnitudes and specified power flows. Guidelines and methods for implementing FACTS devices and their adjustments within the Newton-Rapshon algorithm are described. It is shown that large increments in the adjustments of FACTS devices and nodal network state variables during the backward substitution may dent the algorithm's quadratic convergence. Suitable strategies are given which avoid large changes in these variables and retain the Newton-RapshRapshon method's quadratic convergence. The influence of initial conditions of FACTS devices state variables on the iterative process is investigated. Suitable initialisation guidelines are recommended. Where appropriate, analytical equations are given to assure good initial conditions.

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Lawson, Emily J. R. « Molecular and genetic analysis of a modified Ac transposon in Arabidopsis ». Thesis, University of East Anglia, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332052.

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Chen, Yu Ju. « A comprehensive electromagnetic analysis of AC losses in large superconducting cables ». Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/41418.

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Dey, Sourav. « Large-Signal Analysis of Buck and Interleaved Buck DC-AC Converters ». Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1409578634.

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Shen, Li. « Model integration and control interaction analysis of AC/VSC HVDC system ». Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/model-integration-and-control-interaction-analysis-of-acvsc-hvdc-system(2d4bcb21-a97f-4c7f-b413-1a2a54086145).html.

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The development of voltage source converter (VSC) based high voltage direct current (HVDC) transmission has progressed rapidly worldwide over the past few years. The UK transmission system is going through a radical change in the energy landscape which requires a number of VSC HVDC installations to connect large Round 3 windfarms and for interconnections to other countries. For bulk power long distance transmission, VSC HVDC technology offers flexibility and controllability in power flow, which can benefit and strengthen the conventional AC system. However, the associated uncertainties and potential problems need to be identified and addressed. To carry out this research, integrated mathematical dynamic AC/DC system models are developed in this thesis for small disturbance stability analysis. The fidelity of this research is further increased by developing a dynamic equivalent representative Great Britain (GB) like system, which is presented as a step-by-step procedure with the intention of providing a road map for turning a steady-state load flow model into a dynamic equivalent. This thesis aims at filling some of the gaps in research regarding the integration of VSC HVDC technology into conventional AC systems. The main outcome of this research is a systematic assessment of the effects of VSC controls on the stability of the connected AC system. The analysis is carried out for a number of aspects which mainly orbit around AC/DC system stability issues, as well as the control interactions between VSC HVDC and AC system components. The identified problems and interactions can mainly be summarized into three areas: (1) the effect of VSC HVDC controls on the AC system electromechanical oscillations, (2) the potential control interactions between VSC HVDC and flexible alternating current transmission systems (FACTS) and (3) the active power support capability of VSC HVDC for improving AC system stability. The effect of VSC controls on the AC system dynamics is assessed with a parametric sensitivity analysis to highlight the trade-offs between candidate VSC HVDC outer control schemes. A combination of analysis techniques including relative gain array (RGA) and modal analysis, is then applied to give an assessment of the interactions – within the plant model and the outer controllers – between a static synchronous compensator (STATCOM) and a VSC HVDC link operating in the same AC system. Finally, a specific case study is used to analyse the capability of VSC HVDC for providing active power support to the connected AC system through a proposed frequency droop active power control strategy.

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Todd, Celia Anne. « The role of communication partners in conversations with people with learning difficulties ». Thesis, University of Exeter, 2012. http://hdl.handle.net/10036/4519.

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This study looks at what happens in informal conversations between three people with learning difficulties (intellectual impairment) and a range of non-disabled partners. It takes a participatory approach using data collected by the participants with learning difficulties who chose their communication partners; these partners included family and staff who were paid to support them. The study uses descriptive statistics to highlight areas where there was apparent asymmetry in the conversations. Conversation Analysis combined with features taken from Systemic Functional Linguistics is then used to look in detail at some of these aspects. Important features identified include turn design, repair, and the use of evaluative language and the contribution of non-verbal aspects in particular eye gaze, gesture and the use of artefacts. The study highlights possible strategies for assessing and supporting more effective and equitable interaction for those with learning difficulties and communication impairment and identifies features that should be considered when training professionals working in the field of learning difficulties.

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Leung, Fung-yee. « The management of intrusion in telephone calls : a study of call-waiting in Cantonese telephone conversations / ». Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18716118.

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Hayter, Thomas. « Ac simulation model for the analysis of register insertion local area networks ». Thesis, University of Hull, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235837.

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Wang, Wenfei. « Analysis, design and applications of digitally controlled bridgeless AC/DC buck converter ». Thesis, The University of Sydney, 2012. https://hdl.handle.net/2123/29157.

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Power factor correction (PFC) is now mandatory in modern power electronic systems due to the awareness of ‘pollution’ to the grid by the current harmonics resulting in the adoption of standards and regulations such as IEC 61000-3-2 to limit the current harmonics in the electricity networlm. To improve the input power factor of power converters, normally a PFC circuit is placed between the grid and the switching converters. In universalline (90V-264V) applications, it is vital to maintain high efficiency across the entire input voltage range for the AC/DC rectifier with a high power factor and low line current distortion. The configuration consisting of a bridge rectifier and a boost converter has been regarded as the most commonly used structure due to its simple circuitry and good power factor performance. However, its relatively high output voltage causes high switching losses of the power semiconductors. In this thesis, a generalised power converter structure using bridgeless and voltage-doubler configurations is developed. A new family of bridgeless PFC converters is derived to improve conversion efficiency, followed by a new digitally controlled bridgeless buck converter operating in discontinuous input voltage mode (DIVM) operation which is analysed in detail. The converter inherits PFC property by adding an input LC filter and operating the converter at a constant duty cycle thereby improving power factor, and achieving high efficiency. In modern power systems, power converters with varying power factor are becoming popular. They could contribute to system power factor (PF) when a large number of converters and non-renewable and renewable energy sources and different types of loads are connected. It would be ideal if all power converters in the power system are able to adjust its PF to provide voltage support of the power system. In addition, integrating varying power factor feature into electronic loads would be a desirable feature for system power quality testing purposes. Furthermore, varying power factor could be applied to dimming fluorescent lamps for daily use and even intermittent or fluctuating loads in manufacturing plants. In this thesis, a buck converter working in DIVM with an adjustable power factor is proposed. Experimental results of a laboratory prototype to verify the analysis and design of the proposed topologies are given. Comparative results based on calculation, simulation and experiment are also given to validate the feasibility of the proposed circuits.

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Li, Gen. « Analysis and protection of HVDC systems subject to ac and dc faults ». Thesis, Cardiff University, 2017. http://orca.cf.ac.uk/110295/.

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Voltage source converter-based (VSC) high-voltage direct-current (HVDC) system is emerging as an important technology for transmitting bulk power over long distances and integrating large-scale renewable energy. However, there are still a number of technical challenges. One of the critical aspects is the fault protection. This thesis focuses on the fault behaviours of the VSC HVDC systems and the connected ac systems when the HVDC system subject to ac or dc faults. In relation to the dc side faults, the operating characteristics of dc circuit breakers (DCCBs) and the application of DCCBs in dc grids were studied. The factors, such as the current limiting reactor and the surge arrester, which affect the performance of a DCCB to interrupt dc fault currents were investigated through simulations. In order to test the effectiveness of utilising DCCBs to isolate dc faults, experimental validation was carried out by applying DCCB prototypes in a three-terminal VSC HVDC test-rig. Different dc fault protection approaches were applied in a meshed dc grid which connects to an ac transmission system with two connection points. This aims to investigate the impact of different dc protection approaches on the stability of the integrated ac/dc system. The dynamic interactions between the ac and dc systems were studied further. In terms of converter ac side fault, single-phase faults which occur in the area between the valve and the interface transformer were studied. The fault characteristics of the valve-side single-phase fault in three converter station configurations were analysed in detail. Fault protection strategies based on the theoretical analysis were proposed and validated through simulations. The study of this research work is expected to contribute to the design of ac and dc fault protection of HVDC systems.

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SHIEH, YI-CHI, et 謝伊琪. « A Gender Pragmatic Analysis of Casual Conversations ». Thesis, 2006. http://ndltd.ncl.edu.tw/handle/27334409589015101511.

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碩士
國立新竹教育大學
國民教育研究所
94
The words and sentences people use changed ceaselessly in the growth life . And one’s talk disclosed whose opinions and ideologies. Actually, people usually applied several pragmatic principles（Cooperative、Politeness、Face-threatening Acts）in order to make causal conversation smoothly. Power and solidarity also influence interacted relationship. Besides, gender shows different behavior in a dialogue. Men usually predominated over others；Women always be an echo. Most research by sociolinguists presented, women became independent from knowledge and feminism. In view of the above, this study tried to understand how gender talk in Taiwan, and accomplished by review of literature、conversation of record、and gender concept of questionnaire. By and large, one group displayed “men are authoritative；women are weak”, the other revealed balance interact but swift changed role in different talking topics. As a result, not only showed gender education didn’t make students realized truly meaning of gender respect, but also let us knew why the feminism couldn’t work successfully in Taiwan；how we face the new language in always new generation！

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Yen, Hui-Chun, et 顏惠君. « Spectroscopic analysis of AC-PDP discharges ». Thesis, 2005. http://ndltd.ncl.edu.tw/handle/69437917486837091863.

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碩士
國立清華大學
工程與系統科學系
93
The purpose of this study is to develop a method of spectroscopic measurement to estimate the trend of electron temperature. A lowering of electron temperature would decrease the 703 nm emission line by reducing the indirect pumping to the upper level. The experiment is focused on the 703 nm/ 585 nm emission strength ratio measured by spectrometer which was used to compute the relations of electron temperature in terms of sustain voltage, filling gas ratio and gas pressure. Because Ne excited state is generated by high energy electrons (18.96 eV), electron energy was much lower in the anode region that electrons were energetic enough to generate Xe excited state, but not enough for Ne excited state. Therefore, an intensified charge coupled device (ICCD) camera with optical filters was used to measure visible emission from neon at 585 nm and 703 nm at cathode area. A simulation code developed by Chen Lung-Chih and Chiang Hung Chi at ESS PDP lab in NTHU is used in this study. The simulation code is a two-dimensional PDP simulator based on fluid model. The simulator is used to calculate electron temperature and compare to this experiment. Increasing voltage would lead to stronger electric field, and electron can get more energy from the strong electric field, so electron temperature increase. The sustain voltage increases from 170 volt to 190 volt, the ratio of 703 nm/ 585 nm increases 3.92% in whole cell, and increases 5.01% in cathode area. The efficiency decreases 7.61%. The Ne ionization energy (21.56 eV) is higher than Xe (12.13 eV). When Xe concentration increases, electrons are more likely to ionize Xe atoms in stead of Ne atoms. Therefore, the average electron temperature is lower for high Xe concentration. The gas ratio increases from 5% Xe to 10% Xe, the ratio of 703 nm/ 585 nm decreases 49.41% in the whole cell, and decreases 50.45% in cathode area. The electron temperature results from the 2-D fluid numerical calculation decreases 15.19% in the whole cell, and decreases 20.22% in cathode area. The efficiency increases 43.76%. The gas pressure increases from 400 torr to 475 torr, the ratio of 703 nm/ 585 nm increases 0.66% in whole cell, and decreases 4.02% in cathode area. The electron temperature results from the 2-D fluid numerical calculation decreases 9.05 % in the whole cell, and decreases 8.06 % in cathode area. The efficiency increases 4.70%. The reason that high gas pressure results in lower electron temperature is the same as high Xe gas ratio. When the Xe gas concentrations change from 5% to 10%, the Xe particle number has doubled. When the gas pressures change from 400 torr to 475 torr, the Xe particle number increases only 18.75%. Therefore, the dependence of electron temperature on gas pressure is weaker than on Xe gas ratio.

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Cheng, Chun-Chieh, et 鄭駿杰. « Reliability Analysis for MRT AC Power Systems ». Thesis, 2007. http://ndltd.ncl.edu.tw/handle/91333921496581242920.

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碩士
國立高雄應用科技大學
電機工程系碩士班
95
In this thesis, an effective method to analysis on the AC power supply system of MRT system based on reliability analysis theory is proposed. Using EXPONDIST (exponential distribution function) in Microsoft Excel to find the reliabilities of the components and representing the system in reliability-block diagram, and then reducing the block diagram to calculate the system reliability, this approach perform convenient and cost –effective.

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Kuan-Hung, Wu, et 吳冠宏. « Analysis and Design for AC-LED Drivers ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/76375161638203764396.

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博士
國立臺灣科技大學
電子工程系
100
This dissertation proposes two AC-LED drivers for different power ratings with minimal additional components in order to improve the performance of the AC-LED lamp while maintaining the benefits. Method I consists of an AC-LED bridge rectifier, a filter inductor and an LED string which is divided into controlled and uncontrolled parts by a MOSFET. The fixed off-time pulse-width modulation (FOT-PWM) is adopted. The influences of the number of LEDs in a bridge rectifier on the peak reverse voltage of the LED and the input current command are investigated. The relationship between the inductance and the maximum input-current ripple is studied. In addition, the effects of the number of LEDs in a series string on the switch voltage rating, input PF, current harmonics, and conversion efficiency are presented. Method II is a high-frequency square-wave current driver. The high PF, meeting requirements of the harmonic current standard IEC 61000-3-2 Class C, accurate output-current regulation, and high efficiency are achieved. The topology is a single-stage, which can be considered as a totem-pole bridgeless PFC boost rectifier combined with a half-bridge inverter. A single-stage topology is proposed for reducing quantity of components and simplifying the control method. The simulation and experimental results of the two proposed AC-LED drivers are demonstrated. The estimated power losses of both methods are then calculated and confirmed with experimental results. Finally, contrast among the two methods and the conventional AC-LED lamp will be stated to verify the practicality of each approach and highlight the improved nuances of each design.

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Thèses sur le sujet « Analysis of conversations (AC) »

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