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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.
231

Differential effects of negative and positive affect on context processing

Becker, Theresa M. January 2007 (has links)
The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on September 15, 2009) Includes bibliographical references.
232

Validating context-aware applications

Wang, Zhimin. January 2008 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2008. / Title from title screen (site viewed Nov. 25, 2008). PDF text: xiii, 173 p. : ill. ; 2 Mb. UMI publication number: AAT 3315261. Includes bibliographical references. Also available in microfilm and microfiche formats.
233

Emoticon usage in task-oriented and socio-emotional contexts in online discussion boards

Yigit, Osman Taner. Losh, Susan Carol. January 2005 (has links)
Thesis (M.S.)--Florida State University, 2005. / Advisor: Dr. Susan Carol Losh, Florida State University, College of Education, Dept. of Educational Psychology and Learning Systems. Title and description from dissertation home page (viewed Sept. 29, 2005). Document formatted into pages; contains ix, 37 pages. Includes bibliographical references.
234

Contextual inference [i.e. interference] single-task versus multi-task learning and influence of concurrent temporal interference /

Maslovat, Dana. January 1900 (has links)
Thesis (M.S.)--University of British Columbia, 2002. / Includes bibliographical references (leaves 96-103).
235

Mechanisms of brightness perception

Robinson, Alan Edward. January 2009 (has links)
Thesis (Ph. D.)--University of California, San Diego, 2009. / Title from first page of PDF file (viewed Oct. 7, 2009). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 57-58).
236

Impact of STS (Context-Based Type of Teaching) in Comparison With a Textbook Approach on Attitudes and Achievement in

January 2011 (has links)
abstract: The purpose of this study was to analyze the impact of a context-based teaching approach (STS) versus a more traditional textbook approach on the attitudes and achievement of community college chemistry students. In studying attitudes toward chemistry within this study, I used a 30-item Likert scale in order to study the importance of chemistry in students' lives, the importance of chemistry, the difficulty of chemistry, interest in chemistry, and the usefulness of chemistry for their future career. Though the STS approach students had higher attitude post scores, there was no significant difference between the STS and textbook students' attitude post scores. It was noted that females had higher postattitude scores in the STS group, while males had higher postattitude scores in the textbook group. With regard to postachievement, I noted that males had higher scores in both groups. A correlation existed between postattitude and postachievement in the STS classroom. In summary, while an association between attitude and achievement was found in the STS classroom, teaching approach or sex was not found to influence attitudes, while sex was also not found to influence achievement. These results, overall, suggest that attitudes are not expected to change on the basis of either teaching approach or gender, and that techniques other than changing the teaching approach would need to be used in order to improve the attitudes of students. Qualitative analysis of an online discussion activity on Energy revealed that STS students were able to apply aspects of chemistry in decision making related to socioscientific issues. Additional analysis of interview and written responses provided insight regarding attitudes toward chemistry, with respect to topics of applicability of chemistry to life, difficulties with chemistry, teaching approach for chemistry, and the intent for enrolling in additional chemistry courses. In addition, the surveys of female students brought out subcategories with regard to emotional and professional characteristics of a good teacher, under the category of characteristics of teaching approach. With respect to the category of course experience, subcategories of useful knowledge to solve real-life problems and knowledge for future career were revealed. The differences between the control group females and STS group females with respect to these characteristics was striking and threw insight into how teacher behavior and teaching approach shape student attitudes to chemistry in case of female students. / Dissertation/Thesis / Ph.D. Curriculum and Instruction 2011
237

Compiling Java in linear nondeterministic space

Donnoe, Joshua January 1900 (has links)
Master of Science / Department of Computer Science / Torben Amtoft / Shannon’s and Chomsky’s attempts to model natural language with Markov chains showed differing gauges of language complexity. These were codified with the Chomsky Hierarchy with four types of languages, each with an accepting type of grammar and au- tomaton. Though still foundationally important, this fails to identify remarkable proper subsets of the types including recursive languages among recursively enumerable languages. In general, with Rice’s theorem, it is undecidable whether a Turing machine’s language is re- cursive. But specifically, Hopcroft & Ullman show that the languages of space bound Turing machines are recursive. We show the converse also to be true. The space hierarchy theorem shows that there is a continuum of proper subsets within the recursive languages. With Myhill’s description of a linear bounded automata, Landweber showed that they accept a subset of the type 1 languages including the type 2 languages. Kuroda expanded the definition making the automata nondeterministic and showed that nondeterministic linear space is the set of type 1 languages. That only one direction was proven deterministically but both nondeterministically, would suggest that nondeterminism increases expressiveness. This is further supported by Savitch’s theorem. However, it is not without precedent for predictions in computability theory to be wrong. Turing showed that Hilbert’s Entschei- dungsproblem is unsolvable and Immerman disproved Landweber’s belief that type 1 lan- guages are not closed under complementation. Currently, a major use of language theory is computer language processing including compilation. We will show that for the Java programming language, compilability can be computed in nondeterministic linear space by the existence of a (nondeterministic) linear bounded automaton which abstractly computes compilability. The automaton uses the tra- ditional pipeline architecture to transform the input in phases. The devised compiler will attempt to build a parse tree and then check its semantic properties. The first two phases, lexical and syntactical analysis are classic language theory tasks. Lexical analysis greedily finds matches to a regular language. Each match is converted to a token and printed to the next stream. With this, linearity is preserved. With a Lisp format, a parse tree can be stored as a character string which is still linear. Since the tree string preserves structural information from the program source, the tree itself serves as a symbol table, which normally would be separately stored in a readable efficient manner. Though more difficult than the previous step, this will also be shown to be linear. Lastly, semantic analysis, including typechecking, and reachability are performed by traversing the tree and annotating nodes. This implies that there must exist a context-sensitive grammar that accepts compilable Java. Therefore even though the execution of Java programs is Turing complete, their compilation is not.
238

Advancing the objective measurement of physical activity and sedentary behaviour context

Loveday, Adam January 2017 (has links)
Objective data from national surveillance programmes show that, on average, individuals accumulate high amounts of sedentary time per day and only a small minority of adults achieve physical activity guidelines. One potential explanation for the failure of interventions to increase population levels of physical activity or decrease sedentary time is that research to date has been unable to identify the specific behavioural levers in specific contexts needed to change behaviour. Novel technology is emerging with the potential to elucidate these specific behavioural contexts and thus identify these specific behavioural levers. Therefore the aims of this four study thesis were to identify novel technologies capable of measuring the behavioural context, to evaluate and validate the most promising technology and to then pilot this technology to assess the behavioural context of older adults, shown by surveillance programmes to be the least physically active and most sedentary age group. Study one Purpose: To identify, via a systematic review, technologies which have been used or could be used to measure the location of physical activity or sedentary behaviour. Methods: Four electronic databases were searched using key terms built around behaviour, technology and location. To be eligible for inclusion papers were required to be published in English and describe a wearable or portable technology or device capable of measuring location. Searches were performed from the inception of the database up to 04/02/2015. Searches were also performed using three internet search engines. Specialised software was used to download search results and thus mitigate the potential pitfalls of changing search algorithms. Results: 188 research papers met the inclusion criteria. Global positioning systems were the most widely used location technology in the published research, followed by wearable cameras and Radio-frequency identification. Internet search engines identified 81 global positioning systems, 35 real-time locating systems and 21 wearable cameras. Conclusion: The addition of location information to existing measures of physical activity and sedentary behaviour will provide important behavioural information. Study Two Purpose: This study investigated the Actigraph proximity feature across three experiments. The aim of Experiment One was to assess the basic characteristics of the Actigraph RSSI signal across a range of straight line distances. Experiment Two aimed to assess the level of receiver device signal detection in a single room under unobstructed conditions, when various obstructions are introduced and the impacts these obstructions have on the intra and inter unit variability of the RSSI signal. Finally, Experiment Three aimed to assess signal contamination across multiple rooms (i.e. one beacon being detected in multiple rooms). Methods: Across all experiments, the receiver(s) collected data at 10 second epochs, the highest resolution possible. In Experiment One two devices, one receiver and one beacon, were placed opposite each other at 10cm increments for one minute at each distance. The RSSI-distance relationship was then visually assessed for linearity. In Experiment Two, a test room was demarcated into 0.5 x 0.5 m grids with receivers simultaneously placed in each demarcated grid. This process was then repeated under wood, metal and human obstruction conditions. Descriptive tallies were used to assess the signal detection achieved for each receiver from each beacon in each grid. Mean RSSI signal was calculated for each condition alongside intra and inter-unit standard deviation, coefficient of variation and standard error of the measurement. In Experiment Three, a test apartment was used with three beacons placed across two rooms. The researcher then completed simulated conditions for 10 minutes each across the two rooms. The percentage of epochs where a signal was detected from each of the three beacons across each test condition was then calculated. Results: In Experiment One, the relationship between RSSI and distance was found to be non-linear. In Experiment Two, high signal detection was achieved in all conditions; however, there was a large degree of intra and inter-unit variability in RSSI. In Experiment Three, there was a large degree of multi-room signal contamination. Conclusion: The Actigraph proximity feature can provide a binary indicator of room level location. Study Three Purpose: To use novel technology in three small feasibility trials to ascertain where the greatest utility can be demonstrated. Methods: Feasibility Trial One assessed the concurrent validity of electrical energy monitoring and wearable cameras as measures of television viewing. Feasibility Trial Two utilised indoor location monitoring to assess where older adult care home residents accumulate their sedentary time. Lastly, Feasibility Trial Three investigated the use of proximity sensors to quantify exposure to a height adjustable desk Results: Feasibility Trial One found that on average the television is switched on for 202 minutes per day but is visible in just 90 minutes of wearable camera images with a further 52 minutes where the participant is in their living room but the television is not visible in the image. Feasibility Trial Two found that residents were highly sedentary (sitting for an average of 720 minutes per day) and spent the majority of their time in their own rooms with more time spent in communal areas in the morning than in the afternoon. Feasibility Trial Three found a discrepancy between self-reported work hours and objectively measured office dwell time. Conclusion: The feasibility trials outlined in this study show the utility of objectively measuring context to provide more detailed and refined data. Study Four Purpose: To objectively measure the context of sedentary behaviour in the most sedentary age group, older adults. Methods: 26 residents and 13 staff were recruited from two care homes. Each participant wore an Actigraph GT9X on their non-dominant wrist and a LumoBack posture sensor on their lower back for one week. The Actigraph recorded proximity every 10 seconds and acceleration at 100 Hz. LumoBack data were provided as summaries per 5 minutes. Beacon Actigraphs were placed around each care home in the resident s rooms, communal areas and corridors. Proximity and posture data were combined in 5 minute epochs with descriptive analysis of average time spent sitting in each area produced. Acceleration data were summarised into 10 second epochs and combined with proximity data to show the average count per epoch in each area of the care home. Mann-Whitney tests were performed to test for differences between care homes. Results: No significant differences were found between Care Home One and Care Home Two in the amount of time spent sitting in communal areas of the care home (301 minutes per day and 39 minutes per day respectively, U=23, p=0.057) or in the amount of time residents spent sitting in their own room (215 minutes per day and 337 minutes per day in Care Home One and Two respectively, U=32, p=0.238). In both care homes, accelerometer measured average movement increases with the number of residents in the communal area. Conclusion: The Actigraph proximity system was able to quantify the context of sedentary behaviour in older adults. This enabled the identification of levers for behaviour change which can be used to reduce sedentary time in this group. Overall conclusion: There are a large number of technologies available with the potential to measure the context of physical activity or sedentary time. The Actigraph proximity feature is one such technology. This technology is able to provide a binary measure of proximity via the detection or non-detection of Bluetooth signal: however, the variability of the signal prohibits distance estimation. / The Actigraph proximity feature, in combination with a posture sensor, is able to elucidate the context of physical activity and sedentary time.
239

I am a Merry Midwest Mestizo: Race, Space, and the Landscaping of Identity

Hanley-Tejeda, David Alva 01 August 2014 (has links)
This dissertation examines my regional identity-in-context. First, I frame opening questions related to space, race, landscape, and identity, using the metaphor of walking. Secondly, I outline my notion of "mixed methods" for the study, which I call "a moving methodological mestizaje." Third, I weave personal narrative and poetry to I examine what it means to come to racial consciousness as a biracial, mixed-race person of color in the Midwest-South. Reflecting on the geographic and cultural features of Southern Illinois, I come to understand the region of the country as a "borderlands." Following Gloria Anzaldúa's writing, I identify myself as "a mestizo," or person of mixed race ancestry, but in the context of the Southern Illinois. The title poem of the dissertation expands on "mulatez" or African mestizaje to articulate an Afro-Latino political alliance. Fourth, I explore multiple space that I have lived across the country, to examine qualities of Whiteness to ultimately work against White identity. Then, I deploy the metaphor of drinking hot sauce as a reclaiming Mexican, Aztec mythopoetic. I come to name myself as "Merry Midwest Mestizo," to fully embrace my biracial, Latino, and White self and to find my identity-in-context. Finally, I offer a reclamation of my Mexican mother's life and death using Gloria Anzaldúa's notion of "autohistoria." I close with further ramifications of the study.
240

CAMPOS: A context-aware model for positioning in outdoor environments that supports loosely coupled mobile activities

Moreno Córdova, Daniel Antonio January 2017 (has links)
Doctor en Ciencias, Mención Computación / En escenarios ubicuos, conocer la posición de un dispositivo es imperativo para proveer al usuario de servicios personalizados basados en location awareness, un aspecto de diseño clave en la mayoría de las aplicaciones ubicuas que dependiente de las capacidades de los dispositivos para sentir cambios en su ambiente de trabajo. No existe una solución que aborde todos los tipos de posicionamiento, pues distintos tipos de aplicaciones requieren información de posicionamiento variada en términos de exactitud, precisión, complejidad, escalabilidad, y costo. En escenarios ubicuos estándar, suele más de una estrategia de posicionamiento disponible, pero en general los dispositivos móviles no son capaces de determinar cuál es la más adecuada dado el contexto de trabajo del usuario. Además, este contexto está en constante cambio a medida que el usuario se mueve, perdiéndose conexiones a ciertos elementos del ambiente y ganándose otras. Aunque existen soluciones que abordan el posicionamiento en escenarios específicos de manera efectiva, hacerlo tomando en cuenta la mayoría de estos escenarios sigue siendo un problema abierto. La propuesta presentada en esta tesis es un modelo de posicionamiento sensible al contexto (CAMPOS), que permite a dispositivos que realizan actividades débilmente acopladas en escenarios ad-hoc al aire libre, elegir estrategias de posicionamiento adecuadas a su contexto, basado en variables contextuales predefinidas. El modelo elabora un "catálogo" de estrategias disponibles y los puntos de referencia, usando las variables contextuales como entrada para un clasificador RandomForest, el cual determina un orden de idoneidad para las estrategias de posicionamiento, lo que permite acceder a estrategias ajustadas al contexto del usuario. CAMPOS fue diseñado usando una metodología iterativa basada en casos de estudio. Primero, se realizó una revisión de literatura para determinar umbrales y valores promedio iniciales para las métricas y variables del modelo. Luego, se implementaron dos conjuntos de simulaciones; el primero para experimentar con distintos escenarios y configuraciones de dispositivos; y el segundo para evaluar el rendimiento del modelo. La batería de pruebas incluyó 27 plantillas de escenario, ejecutadas 15 veces para un total de 405 experimentos. Las variables observadas incluyen el efecto de variar la cantidad de beacons (dispositivos con capacidad de posicionamiento), la cantidad total de dispositivos, y el rango de comunicación. Todos los experimentos presentados en este trabajo se realizaron utilizando el ns-3, un simulador de redes de eventos discretos orientado a la investigación. El aporte de CAMPOS reside en que no es una nueva propuesta de estrategia de posicionamiento, ni busca mejorar el estado del arte en términos de precisión. En vez de ello, proporciona a los dispositivos de una red los medios para censar su entorno y determinar qué estrategia de posicionamiento es más adecuada para su contexto. Además, dado que CAMPOS es independiente del proceso formal de posicionamiento, si apareciesen nuevas estrategias de posicionamiento en el futuro, éstas podrían añadirse a CAMPOS con relativa facilidad, permitiendo que los dispositivos potencialmente tengan acceso a dichas estrategias a través del modelo. / El trabajo presentado en esta tesis ha sido financiado por el Programa de Becas NIC Chile, y parcialmente por Fondecyt (Chile), Proyecto 1150252

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