A year-long study was conducted in Pinal County, Arizona to characterize fine and coarse particulate matter as a means of furthering our understanding of ambient concentrations and composition in rural, arid environments. Detailed measurement of ambient fine and coarse mass, ion, metal, and carbon concentrations at one-in-six day resolution was conducted at three sites from February 2009 to February 2010. Detailed organic carbon speciation was collected at 5-week resolution. A series of samples representing native soil, agricultural soil, road dust, and cattle feed lot material was collected, resuspended in the laboratory, and analyzed to provide a chemical source profile for each soil type yielding insights into unique source signatures. Observations within the chemical speciation data and subsequent modeling analysis show a strong impact from local sources at the Cowtown site where mass concentrations are highest. Source apportionment results confirm the significant impact from the cattle feedlot adjacent to the site. Chemical analysis of ambient particles and local feedlot material shows the presence of chemical marker species including phosphate which is unique to this source. Fugitive dust is a significant contributor to ambient particulate matter concentrations at all monitoring locations. Seasonal observations show higher concentrations during tilling and harvesting indicating the large role agricultural sources play on particle concentrations in this area. Chemical characterization and modeling show that re-entrained road dust is a significant factor. Fine particle modeling results indicate that concentrations are influenced significantly by motor vehicles including impacts from direct emissions including brake wear and indirect emissions including resuspended road dust. A significant fraction is also associated with crustal sources while about 5 g/m3 appears to be transported into the region from beyond the air shed. Detailed analysis of the local monsoon season indicates that monsoon rains serve to clean the atmosphere resulting in a marked decrease in ambient coarse mass and resulted in a period where local coarse PM concentrations measured at all sites became more uniform. The monsoon season also featured localized high wind events which severely increased coarse PM concentrations and often caused exceedences of the PM National Ambient Air Quality Standard.

Este trabajo se basa en el uso de entornos oportunísticos, los cuales se caracterizan por aprovechar el tiempo en que las máquinas permanecen ociosas para ejecutar procesos de usuarios. Una parte fundamental de estos entornos consiste en gestionar procesos concurrentes que constituyen una aplicación paralela. En sistemas oportunísticos el objetivo del gestor de recursos es doble: por una lado ha de proveer tiempos de ejecución razonables (los usuarios desean obtener sus procesos acabados cuanto antes), y por el otro ha de proveer buena eficiencia, esto es, buen uso de los recursos, lo cual constituye el objetivo fundamental de un sistema que desea soportar grandes cantidades de cómputo durante largos períodos de tiempo.El desarrollo de un gestor de recursos adecuado para aplicaciones paralelas que se ejecutan en entornos oportunísticos incluye varios aspectos. En particular, este trabajo aborda tres de ellos:- Determinar el número de máquinas, pertenecientes a un entorno oportunístico, necesarias para ejecutar una aplicación, de manera tal que se obtenga buena eficiencia y buen tiempo de ejecución.- Planificar las tareas a las máquinas asignadas.- Reducir los efectos negativos producidos sobre una aplicación, cuando una máquina es reclamada por su dueño, lo que implica que el proceso que ejecuta allí debe dejar dicha máquina.En este trabajo se han considerado aplicaciones de tipo master-worker. El master envía tareas a los workers y recoge los resultados. Este proceso se repite varios ciclos, hasta que se produce una condición de finalización.Para asignar las tareas de la aplicación master-worker a las máquinas disponibles se ha propuesto una política de planificación dinámica denominada Random & Average. Esta política se evaluó por simulación, y los resultados muestran que su comportamiento es parecido al de políticas que necesitan información a-priori sobre el tiempo de ejecución de las tareas. También se dedujo la existencia del Intervalo Ideal, que corresponde al intervalo entre los números de máquinas mínimo y máximo para ejecutar la aplicación de manera tal que se obtenga una buena relación entre el tiempo de ejecución y la eficiencia.Luego se propuso un algoritmo para ajustar dinámicamente el número de máquinas, de manera tal que cualquier aplicación master-worker se ejecute con un número de máquinas perteneciente al intervalo ideal. Esta estrategia se implemento tanto en entornos homogéneos como heterogéneos, utilizando una aplicación encargada de obtener el esqueleto de imágenes.En un entorno oportunístico las máquinas pueden participar o dejar de participar en la ejecución de una aplicación, si son cedidas o reclamadas por sus dueños. Cuando una máquina es reclamada, el proceso que se ejecuta en dicha máquina debe ser detenido y debe dejar esa máquina inmediatamente. Si dicho proceso pertenece a una aplicación paralela, el rendimiento de toda esa aplicación se verá afectado negativamente. Dicho impacto se evaluó, y para disminuirlo se propusieron diferentes estrategias basados en utilizar máquinas extra y en duplicación de tareas. Estas estrategias se estudiaron primero por simulación y luego fueron implementadas. / This work focuses on the use of opportunistic environments, which are characterized by harnessing idle times of machines for executing user jobs. Management of the concurrent jobs constituting a parallel application is an integral part of such non-dedicated systems. In non-dedicated opportunistic environments, the resource manager's goal is to provide both a reasonable execution time (as users are interested in having their job finished as soon as possible), and good efficiency, i.e., good resource usage, which is the main goal of the system in order to obtain high throughput.The development of effective resource management for parallel applications running on opportunistic systems involves a great number of issues. In particular, this work deals with three of them:- Determining and allocating the number of machines, from the pool of machines belonging to the opportunistic system, needed for executing an application obtaining both a good execution time and a good efficiency. - Scheduling application tasks to the assigned computational resources.- Reducing the negative effects produced on an application when a machine belonging to a non-dedicated environment is reclaimed by its owner, and should therefore be released by the task running on it. Throughout this work master-worker applications have been considered. In these applications, there is a master that sends tasks to workers and collects the results. This process is repeated over a number of cycles until an end condition is reached. In order to assign tasks belonging to a master-worker application to machines belonging to an opportunistic environment, we proposed a dynamic scheduling policy called Random & Average. This policy was first evaluated by simulation, and results showed that it exhibits a similar behavior with respect to other policies requiring information in advance about the execution time of the tasks. We also derived the existence of the ideal interval, which corresponds to the interval comprised between the minimum and maximum number of machines for executing the application that obtain a good trade-off between execution time and efficiency. Then we proposed an algorithm for dynamically adjusting the number of machines, for executing any master-worker application, to a number of machines belonging to the ideal interval. This strategy was implemented and evaluated on both homogeneous and heterogeneous environments, with a master-worker thinning application.In an opportunistic environment machines can join and leave the computation as they are released or reclaimed by their owners. When a machine is reclaimed, the job running on that machine must be stopped and vacated. If this job belongs to a parallel application, the whole performance will be negatively affected. We evaluate this impact, and then, in order to alleviate it, propose strategies based on using extra machines and task replication. These strategies were first evaluated by simulation and then implemented and tested in a real environment.

El propósito de este estudio es analizar los antecedentes de las intenciones empresariales y los factores que influyen la transición de las intenciones al comportamiento empresarial (creación de la empresa). Son diversas las contribuciones de este estudio: (1) la evaluación de los determinantes de las intenciones implica mayor entendimiento del comportamiento lo que promueve el desarrollo de programas y políticas que impacten el comportamiento empresarial a través de las actitudes, (2) el análisis de los supuestos de de teorías de conducta planificada, específicamente los determinantes de las intenciones pondrá a prueba la validez de estas teorías en el campo empresarial, y (3) la evaluación de las transiciones durante el proceso de creación de empresas (desde la formulación de la intención hasta el comportamiento empresarial) incrementa nuestro conocimiento sobre el proceso de creación de empresas y los factores que promueven el nacimiento de la organización. Este último aspecto es de particular importancia debido a que la literatura demuestra que la relación entre intenciones y comportamiento es imperfecta (aproximadamente 30%). Dos muestras fueron utilizadas para arrojar luz sobre el proceso de creación de empresas en Puerto Rico: (1) datos del ‘Global Entrepreneurship Monitor’ y (2) empresarios nacientes. El ‘Global Entrepreneurship Monitor’ es un programa de investigación internacional que monitorea la actividad empresarial en las regiones y nos provee información (datos) para examinar los antecedentes a las intenciones empresariales (primera fase en el proceso de creación de empresas). A fines de evaluar los factores que impactan en la transición de intenciones empresariales y comportamiento empresarial se utilizo una muestra de individuos con intenciones empresariales (empresarios nacientes de un Centro de Desarrollo Empresarial en Puerto Rico, SBDCs por sus siglas en inglés). Se realizaron encuestas telefónicas con empresarios nacientes para evaluar los factores que impactan la transición de intenciones empresariales a comportamiento empresarial. Estadísticos descriptivos y de inferencia como el Análisis de Varianza fueron utilizados para resumir los resultados. Se utilizó análisis de regresión para corroborar las hipótesis. Finalmente, se discuten modelos de ecuaciones estructuradas en nuestro intento de desarrollar un modelo integrador de creación de empresas. En general, los resultados de esta investigación sugieren que aunque los modelos de intenciones proveen un marco de referencia para predecir comportamiento, hay mucho más envuelto en la predicción de conductas complejos como el comportamiento empresarial (creación de empresas). / The purpose of this study is to analyze the antecedents of entrepreneurial intentions; and the factors that influence the transition from intentions to entrepreneurial behavior (firm birth). The contributions are numerous: (1) evaluating the key determinants of intentions implies understanding behavior, which can lead to the development of policy that influences entrepreneurial behavior through attitudes; (2) analyzing the key assumptions of theories of planned behavior, specifically determinants of intentions will put to the test the validity of this theory within the entrepreneurial field; (3) assessing the transitions during the venture process (from intentions to firm behavior) increases our understanding of the entrepreneurial process and the factors that lead to the emergence of an organization, particularly when the relationship between intentions and behavior is imperfect (30%). Two samples were used to provide insights into the venture creation process in Puerto Rico: (1) Global Entrepreneurship Monitor Data and (2) nascent entrepreneurs. The Global Entrepreneurship Monitor, international research program that monitors entrepreneurial activity of regions, provided data to test the determinants of entrepreneurial intentions, the first stage in the entrepreneurial process. To examine the factors that influence the intention-behavior relationship we used a sample of individuals who manifested entrepreneurial intentions (nascent entrepreneurs from SBDCs). Telephone interviews (survey) were conducted with reported nascent entrepreneurs to evaluate the transitions from realized intentions to behavior. Results were summarized using descriptive statistics and inferential statistics such as Analysis of Variance (ANOVA). Multiple regression analysis was conducted to test the hypotheses. Finally, Structural Equation Models were developed in attempts to construct an overall model of venture creation. In general the findings suggest that although intentional models provide a framework to predict future behavior, there is still much more involved in the prediction of behavioral outcomes such as entrepreneurial behavior.

Deictic pointing—pointing at things during conversations—is natural and ubiquitous in human communication. Deictic pointing is important in the real world; it is also important in collaborative virtual environments (CVEs) because CVEs are 3D virtual environments that resemble the real world. CVEs connect people from different locations, allowing them to communicate and collaborate remotely. However, the interaction and communication capabilities of CVEs are not as good as those in the real world. In CVEs, people interact with each other using avatars (the visual representations of users). One problem of avatars is that they are not expressive enough when compare to what we can do in the real world. In particular, deictic pointing has many limitations and is not well supported. This dissertation focuses on improving the expressiveness of distant pointing—where referents are out of reach—in desktop CVEs. This is done by developing a framework that guides the design and development of pointing techniques; by identifying important aspects of distant pointing through observation of how people point at distant referents in the real world; by designing, implementing, and evaluating distant-pointing techniques; and by providing a set of guidelines for the design of distant pointing in desktop CVEs. The evaluations of distant-pointing techniques examine whether pointing without extra visual effects (natural pointing) has sufficient accuracy; whether people can control free arm movement (free pointing) along with other avatar actions; and whether free and natural pointing are useful and valuable in desktop CVEs. Overall, this research provides better support for deictic pointing in CVEs by improving the expressiveness of distant pointing. With better pointing support, gestural communication can be more effective and can ultimately enhance the primary function of CVEs—supporting distributed collaboration.

Researchers have studied the positive effect of healing outdoor environments on hospitalized children, their family members and staff's health and mood. Consequently many modern hospitals dedicate portions of their space to healing outdoor environments. However, these amenities are underutilized due to various design barriers. This research aimed to identify barriers to garden visitation and introduce design guidelines that encourage garden visitation in pediatric hospitals for all groups. Five Texas pediatric hospital gardens were selected to examine the impact of availability of shade, quality and availability of seats, and presence of the healing nature on user satisfaction and garden use. Behavioral observation, surveys, interviews, and site evaluations were conducted. Gardens were ranked based on design qualities, user satisfaction, and frequency and duration of garden visitation. The primary conclusion of this study was that garden visitors' satisfaction with design is positively correlated with presence and quality of hypothesis variables. Duration and frequency of garden visitation also increased in gardens with better shading, seating options, and planting. Other factors identified as influential in increasing garden use included availability of amenities for children and playfulness of design layout. The research findings were instrumental in introducing new design guidelines for future hospital garden design projects. In addition, they served to statistically support design guidelines suggested by previous researchers.

Thesis (M.A.)--Boise State University, 2009. / Includes bibliographical references (leaves 97-102).

Thesis (Ph. D.)--University of Canterbury, 2009. / Typescript (photocopy). Includes bibliographical references. Also available via the World Wide Web.

For the past few years, virtual environments (VEs) have gained broad attention from both scholarly and practitioner communities. However, in spite of intense and widespread efforts, most VE-related research has focused on the technical aspects of applications, and the necessary theoretical framework to assess the quality of interfaces and designs has not yet been fully developed. This research, as a response to such challenges, concerns the usability of three-dimensional VEs. More specifically, this study aims to investigate the effects of wayfinding affordance design on users’ task performance and perceptual experience in 3D desktop VEs. For this purpose, four different wayfinding affordance conditions were set up: Fixed Detached Affordance Cues (FDAC) condition, Switchable Detached Affordance Cues (SDAC) condition, Portable Embedded Affordance Cues (PEAC) condition and Fixed Embedded Affordance Cues (FEAC) condition. Maps and directional cues were employed to implement wayfinding affordance. The results show that the design of wayfinding affordance has significant effects on users’ perceptual experience as well as their task performance. Task performance was significantly better where the maps and directional cues were provided independently from the VE interfaces (FDAC, SDAC). With regard to perceptual experience, the effect was significant only in simple environments. In these environments, the fixed and, therefore, stable interfaces (FEAC, FDAC) were found to provide a better sense of presence for users whereas the manipulative interfaces (PEAC, SDAC) offered a greater state of playfulness. The research findings also indicated that the design of 3D interfaces had a greater impact on non-expert users than on expert users. / text

When operating microsystems in harsh environments, many conventionally used techniques are limiting. Further, depending on if the demands arise from the environment or the conditions inside the system, different approaches have to be used. This thesis deals with the challenges encountered when microsystems are used at high pressures and high temperatures. For microsystems operating at harsh conditions, many parameters will vary extensively with both temperature and pressure, and to maintain control, these variations needs to be well understood. Covered within this thesis is the to-date strongest membrane micropump, demonstrated to pump against back-pressures up to 13 MPa, and a gas-tight high pressure valve that manages pressures beyond 20 MPa. With the ability to manipulate fluids at high pressures in microsystems at elevated temperatures, opportunities are created to use green solvents like supercritical fluids like CO2. To allow for a reliable and predictable operation in systems using more than one fluid, the behavior of the multiphase flow needs to be controlled. Therefore, the effect of varying temperature and pressure, as well as flow conditions were investigated for multiphase flows of CO2 and H2O around and above the critical point of CO2. Also, the influence of channel surface and geometry was investigated. Although supercritical CO2 only requires moderate temperatures, other supercritical fluids or reactions require much higher temperatures. The study how increasing temperature affects a system, a high-temperature testbed inside an electron microscope was created. One of the challenges for high-temperature systems is the interface towards room temperature components. To circumvent the need of wires, high temperature wireless systems were studied together with a wireless pressure sensing system operating at temperatures up to 1,000 °C for pressures up to 0.3 MPa. To further extend the capabilities of microsystems and combine high temperatures and high pressures, it is necessary to consider that the requirements differs fundamentally. Therefore, combining high pressures and high temperatures in microsystems results in great challenges, which requires trade-offs and compromises. Here, steel and HTCC based microsystems may prove interesting alternatives for future high performance microsystems.

The demands upon the social care workforce in the UK are only likely to increase over the next decades. The social care sector is heavily reliant on NVQs and this is regulated through the Care Standards Act (2000). It is thus important that these qualifications appropriately support staff development. The purpose of the research was to explore this in one social care organisation (Homecare) through researching staff perspectives on factors that inhibited or supported learning through NVQs and to examine the Homecare/Centre delivery of NVQs and workplace learning with this in mind. The research is broadly qualitative in design and draws on the principles of narrative research combined with analysis focused on key themes (interpersonal, personal and organisational factors). The research found that an understanding of the key concepts of workplace learning is relevant to the delivery of NVQs and can help these qualifications be implemented successfully as a part of a more holistic approach to teaching, learning and the assessment of competence in the workplace. The research identified that the organisation had a particular approach that strategically integrated assessment both at organisational and practice level. Additionally the research identified areas within the NVQ process, where integrated assessment proved of benefit to practice through professional level development of skills and knowledge, values and reflective learning and confidence. From this eight key elements of an enhanced model of NVQ delivery were identified that constitute the contribution to practice. The contribution to theory lies in linking the literatures of NVQs, competence and workplace learning and the suggestion that previous understanding of NVQs as behaviourist and atomistic is not as important as the approach to assessment adopted by organisations. The research has relevance to any social care organisation but also to wider audiences where NVQs are used as it adds to understanding of workplace learning through a depth of practitioner-researcher understanding of specific qualifications in a specific context.