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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.
11

The adaptive coupling of heat and air flow modelling within dynamic whole-building simulation

Beausoleil-Morrison, Ian David January 2000 (has links)
This thesis is concerned with advancing the modelling of indoor air flow and internal surface convection within dynamic whole-building simulation. The path taken is the conflation of computational fluid dynamics (CFD) techniques with dynamic whole-building simulation, with an accurate treatment of the co-dependencies between these modelling domains. Two flow responsive modelling techniques were devised and implemented within the ESP-r simulation program to achieve the research objectives. The adaptive convection algorithm enhances ESP-r's thermal simulation domain by dynamically controlling the simulation of internal surface convection. Empirical methods were extracted from the literature and a new method for characterizing mixed flow convective regimes was created to provide the algorithm with a basis of 28 convection coefficient correlations. Collectively these methods can calculate convection coefficients for most flows of practical interest. Working with this suite of correlations, the algorithm assigns appropriate equations to each internal surface and adapts the selection in response to the room's evolving flow regime. The adaptive conflation controller manages all interactions between the thermal and CFD modelling domains. The controller incorporates the latest turbulence modelling advancements applicable for room air flow simulation and possesses a suite of handshaking and thermal boundary condition treatments. The job of this adaptive conflation controller is to monitor the evolving thermal and air flow conditions in the room and dynamically select an appropriate combination of modelling approaches for the prevailing conditions. The two control schemes implemented to demonstrate the controller make use of a double-pass modelling approach. Each time-step that the thermal domain handshakes with CFD, the adaptive conflation controller performs an investigative simulation to approximate the room's flow and temperature field. Using these estimates, the controller calculates dimensionless groupings to determine the nature of the flow (forced, buoyant, mixed, fully turbulent, weakly turbulent) adjacent to each internal surface. This information is used to select suitable boundary condition treatments for each surface. A second CFD simulation is then performed using the refined modelling approach to more accurately resolve the room's air flow and temperature distribution, and to predict surface convection. In order to protect the thermal domain, a two-stage screening process is used to assess (and where necessary reject) the CFD-predicted surface convection estimates. These adaptive modelling techniques advance the modelling of indoor air flow and internal surface convection within whole-building simulation.
12

Aspergillus parasiticus and Coriolus versicolor growth studies in the presence of naphthalene and formaldehyde : fungal growth as a source of, and monitoring system for, sick building syndrome

O'Brien, Geraldine January 2003 (has links)
No description available.
13

Indoor Localization Using Three dimensional Multi-PDs Receiver Based on RSS

Liu, Yinghao 07 1900 (has links)
In modern life, there are many applications where positioning plays an important role. People have developed the global positioning system (GPS) to locate world wide position with error in decameter scales, which brings people much convenience. However, the accuracy of GPS is too low for indoor localization. The signals will drop down due to the signal attenuation caused by construction materials. With the well-developed GPS being indispensable for outdoor activities, many researchers have been also devoted to seeking an indoor positioning system to realize indoor localization with acceptable error. Indoor localization can be very useful in different situations, like locating, tracking, navigation and identification. For example, in the mall, locating the exact goods for customers can provide much convenience and benefits. Locating and tracking in the airport can greatly help passengers save their time and energy in reaching the destination. In another general scenario of identification, the population of observed targets is usually larger than just one. Hence, only with small error, indoor localization system (ILS) can be able to identify the targets despite the neighbors. Due to the emerging and urging demands of increasing the accuracy of indoor localization, we propose a novel design of three dimensional (3-D). optical receiver for visible light communication (VLC) indoor positioning system. First, we model the optical wireless channel. Then we utilize modified triangulation method to obtain more robust receiver position by using at least two light-emitting diodes (LEDs) and one receiver consisting of nine photodetectors (PDs). Finally, the improved algorithm is implemented and the results are shown under our three dimensional multiple photodetectors (multi-PDs) structure receiver. In the simulation, we take the parameters of Lambertian radiation pattern, LEDs and PDs as those shown in [1] . To be noticed, our design of multi-PDs receiver is fully expanded into three dimensions compared with the pyramid receiver (PR), which allows indoor positioning with our receiver structure to be more robust to the higher or corner positions. The details will be explained in the following sections. Based on Multiple-Photodiodebased Indoor Positioning algorithm [1], the indoor positioning algorithm is improved by redefining the optimization problem of obtaining the direction from receiver to LED and using weighted triangulation method to locate receiver position. We admit the solution under the redefined problem is not optimal to the actual problem. Yet, our given solution is better to that in [1] due to the existence of noise, which is reasonable and has been verified.
14

Sensitivity Analysis for Measurements of Multipath Parameters Pertinent to TOA based Indoor Geolocation

Ye, Yunxing 10 May 2010 (has links)
Recently, indoor geolocation technologies has been attracting tremendous attention. For indoor environments, the fine time resolution of ultra-wideband (UWB) signals enables the potential of accurate distance measurement of the direct path (DP) between a number of reference sources and the people or assets of interest. However, Once the DP is not available or is shadowed, substantial errors will be introduced into the ranging measurements, leading to large localization errors when measurements are combined from multiple sources. The measurement accuracy in undetected direct path (UDP) conditions can be improved in some cases by exploiting the geolocation information contained in the indirect path measurements. Therefore, the dynamic spatial behavior of paths is an important issue for positioning techniques based on TOA of indirect paths. The objectives of this thesis are twofold. The first is to analyze the sensitivity of TOA estimation techniques based on TOA of the direct path. we studied the effect of distance, bandwidth and multipath environment on the accuracy of various TOA estimation techniques. The second is to study the sensitivity of multipath parameters pertinent to TOA estimation techniques based on the TOA of the indirect paths. We mainly looked into the effect of distance, bandwidth, threshold for picking paths, and multipath environment on the number of multipath components(MPCs) and path persistency. Our results are based on data from a new measurement campaign conducted on the 3rd floor of AK laboratory. For the TOA estimation techniques based on DP, the line of sight (LOS) scenario provides greatest accuracy and these TOA estimation techniques are most sensitive to bandwidth availability in obstructed line of sight (OLOS) scenario. All the TOA estimation algorithms perform poorly in the UDP scenario although the use of higher bandwidth can reduce the ranging error to some extent. Based on our processed results, The proposal for selecting the appropriate TOA estimation technique with certain constrains is given. The sensitivity study of multipath parameters pertinent to indirect-path-based TOA estimation techniques shows that the number of MPCs is very sensitive to the threshold for picking paths and to the noise threshold. It generally decreases as the distance increase while larger bandwidth always resolves more MPCs. The multipath components behave more persistently in line of sight (LOS) and obstructed line of sight (OLOS) scenarios than in UDP scenarios, and the use of larger bandwidth and higher threshold for picking paths also result in more persistent paths.
15

Introduction

Günzel, Stephan, Liebe, Michael, Mersch, Dieter January 2011 (has links)
No description available.
16

Theorizing navigable space in video games

Wolf, Mark J. P. January 2011 (has links)
Space is understood best through movement, and complex spaces require not only movement but navigation. The theorization of navigable space requires a conceptual representation of space which is adaptable to the great malleability of video game spaces, a malleability which allows for designs which combine spaces with differing dimensionality and even involve non-Euclidean configurations with contingent connectivity. This essay attempts to describe the structural elements of video game space and to define them in such a way so as to make them applicable to all video game spaces, including potential ones still undiscovered, and to provide analytical tools for their comparison and examination. Along with the consideration of space, there will be a brief discussion of navigational logic, which arises from detectable regularities in a spatial structure that allow players to understand and form expectations regarding a game’s spaces.
17

Define real, Moron! : Some remarks on game ontologies

Aarseth, Espen January 2011 (has links)
Academic language should not be a ghetto dialect at odds with ordinary language, but rather an extension that is compatible with lay-language. To define ‘game’ with the unrealistic ambition of satisfying both lay-people and experts should not be a major concern for a game ontology, since the field it addresses is subject to cultural evolution and diachronic change. Instead of the impossible mission of turning the common word into an analytic concept, a useful task for an ontology of games is to model game differences, to show how the things we call games can be different from each other in a number of different ways.
18

Pokéwalkers, mafia dons, and football fans : play mobile with me

Salen, Katie January 2011 (has links)
This paper addresses a theoretical reconfiguration of experience, a repositioning of the techno-social within the domains of mobility, games, and play, and embodiment. The ideas aim to counter the notion that our experience with videogames (and digital media more generally), is largely “virtual” and disembodied – or at most exclusively audiovisual. Notions of the virtual and disembodied support an often-tacit belief that technologically mediated experiences count for nothing if not perceived and valued as human. It is here where play in particular can be put to work, be made to highlight and clarify, for it is in play that we find this value of humanity most wholly embodied. Further, it is in considering the design of the metagame that questions regarding the play experience can be most powerfully engaged. While most of any given game’s metagame emerges from play communities and their larger social worlds (putting it out of reach of game design proper), mobile platforms have the potential to enable a stitching together of these experiences: experiences held across time, space, communities, and bodies. This coming together thus represents a convergence not only of media, participants, contexts, and technologies, but of human experience itself. This coming together is hardly neat, nor fully realized. It is, if nothing else, multifaceted and worthy of further study. It is a convergence in which the dynamics of screen play are reengaged.
19

Fundamental components of the gameplay experience : analysing immersion

Mäyrä, Frans, Ermi, Laura January 2011 (has links)
This co-authored paper is based on research that originated in 2003 when our team started a series of extensive field studies into the character of gameplay experiences. Originally within the Children as the Actors of Game Cultures research project, our aim was to better understand why particularly young people enjoy playing games, while also asking their parents how they perceive gaming as playing partners or as close observers. Gradually our in-depth interviews started to reveal a complex picture of more general relevance, where personal experiences, social contexts and cultural practices all came together to frame gameplay within something we called game cultures. Culture was the keyword, since we were not interested in studying games and play experiences in isolation, but rather as part of the rich meaning- making practices of lived reality.
20

What is visualization?

Manovich, Lev January 2011 (has links)
Over the last 20 years, information visualization became a common tool in science and also a growing presence in the arts and culture at large. However, the use of visualization in cultural research is still in its infancy. Based on the work in the analysis of video games, cinema, TV, animation, Manga and other media carried out in Software Studies Initiative at University of California, San Diego over last two years, a number of visualization techniques and methods particularly useful for cultural and media research are presented.

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