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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.
311

Performance measures for residential PV structural response to wind effects

Goodman, Joseph Neal 27 May 2016 (has links)
This thesis applies structural reliability measures for the performance based design of residential PV system structures. These measures are intended to support designers in delivering systems with quantified and consistent reliability. Existing codified practices prescribe global factors (allowable stress design) and partial factors (load and resistance factor design) intended to provide an acceptable level of reliability as defined by historical practice. When applied to residential PV systems this prescriptive approach has two flaws, (1) calibration efforts needed to ensure consistency across structural system types have not kept up with the commercially available system types and (2) the actual expected reliability is not quantified and available to support decisions. The proposed reliability measures include probability of failure conditioned to wind speed in a fragility curve and the reliability index β, both of which are commonly used in performance based design. The approach is demonstrated through the application of the reliability measures to code compliant designs. Diverse system types are utilized to demonstrate how the existing code prescribed approach may lead to non-uniform structural performance. For each of the system types on which the reliability measures are demonstrated, a code compliant design is developed for three roof slopes, wind tunnel testing is conducted to provide an experimental measure of wind pressure coefficients, system specific fragility curves are generated to quantify the probability of failure conditioned to a set of wind speeds, and then, a site specific wind model is applied to produce a probability of failure and reliability index β. Through the performance based approach proposed in this thesis, two key outputs show non-uniform and unanticipated structural performance of PV systems designed according to the prescriptive code method. The two key outputs which illustrate this finding are fragility curves which illustrate the probability of failure over a range of wind speeds and reliability index, β values which couple the structural and wind distributions for a single measure of reliability.
312

Diffusion of dynamic innovations : A case study of residential solar PV systems

Karakaya, Emrah January 2015 (has links)
In the literature on diffusion of innovations, it is widely known that the characteristics and socio-environmental settings of adopters do evolve in space and time. What about innovations themselves? During the diffusion process, don’t some innovations continuously alter in space and time? If so, how does the dynamic character of an innovation influence the diffusion process? In previous research, it has been often assumed that innovations do not continuously alter or get modified when diffusing from a source to potential adopters. This assumption may mean that the innovation is invariant as it diffuses in time and space—i.e., the innovation does not have a continuously dynamic character. Is it always the case in practice?    A single form of an innovation is not always necessarily compatible with the preferences, limitations, and residential settings of adopters. The innovation might appear in different forms when it diffuses in space and time, i.e., it is “dynamic”. This PhD thesis aims to explore how dynamic innovations diffuse in space and time—a relatively understudied topic in research. In doing so, it distinguishes between the diffusion of dynamic innovations and other kinds of innovations. Anchored on the case of diffusion of residential solar photovoltaic (PV) systems, this thesis is composed of a cover essay and six appended papers. The first two appended papers are systematic literature reviews, aiming at understanding the state of the art of the theoretical and contextual research domains. The third paper is based on a case study in southern Germany and explores the diffusion of a dynamic innovation at adopter level. The fourth paper is empirically focused on a local firm’s business model, which is assumed to be a key to understanding the mechanism behind the diffusion of dynamic innovations. The fifth paper is based on lead market hypothesis and tries to explore the diffusion of innovations at the regional level. The sixth paper studies a semi-hypothetical case and offers an innovative method to forecast the diffusion of innovations in general. The contribution of this PhD thesis lies in three research dimensions: context, method, and theory. Firstly, the thesis takes the existing theories (e.g., diffusion of innovations theory and lead market hypothesis) and methods (e.g., case study) and applies them in different contexts of the diffusion of residential solar PV systems: the individual, sub-national, and national level. Secondly, it proposes a new research method, namely the finite element method for forecasting the diffusion of innovations, based on an existing theory (e.g., wave-like diffusion of innovations in time and space) and context (e.g., solar PV systems). Last but not least, the cover essay of this thesis takes the findings of the appended papers and employs an extension of theory of diffusion of innovations. In doing so, it includes the role of the dynamic characteristic of innovations that do alter in time and space during the diffusion process. Overall, the findings of this thesis indicate that the diffusion of dynamic innovations is different in nature, and continuous efforts of change agents are critical for enhancing the diffusion of such innovations. Change agents are especially important to help potential adopters to find out and develop the form of innovation that best fits their needs, limits, and preferences, which are heterogeneous in space and time. / <p>QC 20151117</p> / European Doctorate in Industrial Management
313

Simulation of Indoor Radon and Energy Recovery Ventilation Systems in Residential Buildings

Akbari, Keramatollah January 2015 (has links)
This study aims to investigate the effects of ventilation rate, indoor air temperature, humidity and using a heat recovery ventilation system on indoor radon concentration and distribution. Methods employed include energy dynamic and computational fluid dynamics simulation, experimental measurement and analytical investigations. Experimental investigations primarily utilize a continuous radon meter and a detached house equipped with a recovery heat exchanger unit. The results of the dynamic simulation show that the heat recovery unit is cost-effective for the cold Swedish climate and an energy saving of about 30 kWh per  floor area per year is possible, while it can be also used to lower radon level. The numerical results showed that ventilation rate and ventilation location have significant impacts on both radon content and distribution, whereas indoor air temperature only has a small effect on radon level and distribution and humidity has no impact on radon level but has a small impact on its distribution.
314

Urban growth in Central Texas : soils and single-family home development

Fasnacht, Steven Benjamin 14 October 2014 (has links)
This study investigates the potential impacts on soils from development practices associated with new single-family residential home construction in the extra territorial jurisdiction (ETJ) of Pflugerville, Texas. My research question is: Are regulations that directly focus on soil conservation advisable within Pflugerville’s ETJ, and what areas of development ought to be primarily targeted by these regulations in order to better ensure the long-term stability of soil health and the minimization of soil loss? The rationale for this question is based on the city’s projected future population growth, the projected future demand for single-family residences, as well as the development and management practices typically associated with new single-family residential development in the ETJ of Pflugerville. I hypothesize that due to Pflugerville’s proximity to Austin and Round Rock, in addition to the relative abundance of available land to the east of the city of Pflugerville, that it is likely to continue experiencing sustained population and residential development growth, particularly in the form of new single-family residences in the ETJ. A population projection was conducted up to the year 2030, which in conjunction with average persons-per-household and single-family home permitting data, estimates potential consumer demand for single-family residences. The imperative to prevent soil loss is conceptually linked to ecosystem service benefits resulting from healthy and intact soils, such as improved water quality and the regulation of peak flow rates during storm events. Single-family residential development is evaluated in terms of conventional on-the-ground construction practices gathered from interviews with developers of single-family homes in the Pflugerville ETJ, as well as planning and regulatory specialists. These analyses are intended to inform regulatory and decision making processes regarding the importance and potential integration of soil preservation and conservation at the individual construction site level. / text
315

Meanings, values, and life course : a study of participants' experiences at a Scottish outdoor education centre

Telford, John Andrew January 2010 (has links)
Residential outdoor education has had a significant formal and informal presence within the education system of the United Kingdom since the 1950s. However, there is little empirical research into the experiences of participants, particularly from a long-term perspective. The present study investigates the meanings, values, and impacts that participants attribute to a five-day residential experience at Ardentinny Outdoor Education Centre, near Dunoon, Scotland. Participants attended the Centre as school pupils between 13 and 16 years of age. Ardentinny Outdoor Education Centre operated as an educational facility under the auspices of the local authority between 1973 and 1996. Participants were contacted between 2007 and 2008, hence a minimum of 11 years after the Centre closed. Semi-structured questionnaires (n = 110) and interviews (n = 14) were used to generate data regarding participants’ experiences. These were analysed using a hermeneutic approach. Supplementary data were generated from archival documents and interviews (n = 29) with various stakeholders in Ardentinny Outdoor Education Centre, ranging from local authority education officers to Centre managers and instructional staff. These supplementary data contribute towards a nuanced interpretive account of participants’ experiences that has both breadth and depth. The data suggest that participants’ experiences at Ardentinny Outdoor Education Centre represented highly significant events in their school career. Principal findings relate to themes of achievement, independence and responsibility, and the development of more adult relationships. Seventy-two percent of questionnaire respondents claimed that their experience at Ardentinny Outdoor Education Centre continued to influence their adult lives. This influence was manifested in a variety of ways ranging from a love of the outdoor environment, to choices regarding use of leisure time, to employment choices. Bourdieu’s (1977, 1990b) theory of social practice, particularly the concepts of field and habitus, provides a framework to interpret participants’ expressions of the nature of their experiences and the impact those experiences did or did not have on their lives. From this perspective Ardentinny Outdoor Education Centre presented participants with a safe and authentic experience that differed sufficiently from their previous life experiences to allow for the opportunity to develop new understandings of self and the social world. These new understandings were expressed in different ways and at different times over participants’ subsequent life course.
316

Prehispanic residence and community at San Estevan, Belize.

Levi, Laura Jane. January 1993 (has links)
Research at the site of San Estevan, Belize begins with the premise that more serious attention must be paid to the significance of residential variability in archaeological modelings of the lowland Maya. A classification of structure groupings is used to track the distribution of San Estevan's diverse residential arrangements across the site. Norms of social structure and economic inequality prove inadequate frameworks to account for the spatial and temporal variation manifest by San Estevan's residential classes, nor do they help to explain the spatial regularities underlying the distributions of these classes. I suggest, instead, that the site's residential units best effect divergent organizational strategies adopted by San Estevan's prehispanic domestic groups. Whereas diffuse political authority, impoverished political economies, and kingroup self-sufficiency traditionally have been invoked to account for Maya residential patterns, domestic strategies at San Estevan gained their shape directly in relation to the functions housed in the community's precincts of monumental architecture. I conclude that prehispanic Maya residential distributions formed through stringent economic and political entailments of community life.
317

Estimating Response to Price Signals in Residential Electricity Consumption

Huang, Yizhang January 2013 (has links)
Based on a previous empirical study of the effect of a residential demand response program in Sala, Sweden, thisproject investigated the economic consequences of consumer behaviour change after a demand-based time ofuse distribution tariff was employed. The economic consequences of consumers were proven to bedisadvantageous in terms of unit electricity price. Consumers could achieve more electricity bill saving throughstabilising their electricity consumption during peak hours, and this way bring least compromising of theircomfort level.In order to estimate the price elasticity of the studies demand response program, a new method of estimationprice elasticity was proposed. With this method, the intensity of demand response of the demand responseprogram was estimated in terms of price elasticity. Regression analysis was also applied to find out the priceincentives of consumer behaviour change. And the results indicated that the rise in electricity supply chargehardly contributes to load reduction, while the demand-based tariff constituted an advantageous solution on loaddemand management. However stronger demand response still
318

Personal recollections and civic responsibilities: dispute resolution and the Indian Residential Schools legacy

Hough, Maegan 29 January 2015 (has links)
The author attended Independent Assessment Process (IAP) hearings as part of the Indian Residential Schools Settlement Agreement. Her experience in IAP hearings raised questions about our approach, as Canadians, to historical wrongs, especially those, like loss of language and culture, which fall outside of the purview of criminal and tort-law. This thesis explores the legal, social, and political dispute resolution mechanisms available in Canada to address harms as they have been applied to the Indian Residential Schools Legacy. It finds that the approach to date has been limited by the assumptions inherent in those institutions. The author proposes that Canadians, as a society, need to reframe and restart our discussion about harms and reparations using a framework of “responsibility”, and provides some possible mechanisms to begin that discussion. / Graduate / mhough@uvic.ca
319

What hinders and promotes the use of CBT in a residential home? : - an interiew study

Berg, Maria, Hansson, Marie January 2014 (has links)
This qualitative study aimed to identify how personnel working in a residential home in Sweden work withCognitive Behavioral Therapy (CBT) orientation within the organization. Semi-structured interviews were conducted with five personnel. The research questions were; How do the personnel describe the CBT orientation? How do the personnel describe the CBT tools and methods? How do the personnel describe and measure the implementation of CBT? The results were analyzed an Interpretive Phenomenological Analysis (IPA) tool in order to gain a greater understanding of the data. The theories used to analyze the results were the learning theory, attachment theory and New Public Management (NPM). The results of this study indicate that CBT was incorporated in the daily lives of the residents throughout the course of the day and the personnel described common methods such as Aggression Replacement Therapy (ART), Dialectal Behavioral Therapy (DBT), and Motivational Interviewing (MI).
320

Integration of Combined Heat and Power Generators into Small Buildings - A Transient Analysis Approach

DeBruyn, Adrian Bryan January 2006 (has links)
Small combined heat and power generators have the potential to reduce energy consumption and greenhouse gas emissions of residential buildings. Recently, much attention has been given to these units. To date, the majority of studies in this field have concentrated on the steady operational performance of a specific generator type, and the available computer models have largely been theoretical in nature. <br /><br /> The main goal of this study was to evaluate the performance of the latest combined heat and power generators, when integrated into Canadian residential homes. A fair comparison of four 1 kW (electrical) units was made. The combined heat and power units studied were based on PEM fuel cell, solid oxide fuel cell, Stirling Engine, and internal combustion engine energy converters. <br /><br /> This study utilized recent test data in an attempt to evaluate the most efficient method of integrating the combined heat and power units into residential houses. Start-up, shut down, and load change transients were incorporated into the simulations. The impact of load variations due to building thermal envelope differences and varying building heating system equipment was evaluated. The simulations were evaluated using TRNSYS software. The building heat demands were determined with eQuest hourly building simulation software. <br /><br /> All of the combined heat and power units under study were capable of providing a net annual benefit with respect to global energy and greenhouse gas emissions. The fuel cells offer the highest integrated performance, followed closely by the internal combustion engine and lastly the Stirling engine. Annual global energy savings up to 20%, and greenhouse gas savings up to 5. 5 tonnes per year can be achieved compared to the best conventional high efficiency appliances. <br /><br /> Heat demand influences performance greatly. As the thermal output of the generator unit approaches half of the average building thermal demand, the system design becomes critical. The system design is also critical when integrating with a forced air furnace. Only the PEM fuel cell unit produces clear global energy and emissions benefits when operating in the summertime.

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