Researchers recommended investing according to the long only momentum (MOM) strategy to generate excess returns for private investors. The general problem of this study was that it was unclear when to enter and when to exit declining financial markets to avoid larger losses and to improve the overall performance with the MOM strategy. Therefore, it was important to understand the influence of a timing indicator on the MOM strategy. The purpose of this study was to examine the relationship between different moving average (MA) settings, the MOM strategy, and the performance of the returns from the construction of small U.S. stock portfolios. The research question was what MA setting as a strategy adjustment could improve the MOM strategy performance for small portfolios of U.S. stocks. A quasi-experimental research design was chosen to answer this research question. For the methods and analysis, simple- and exponential- MA, 2 econometric models, and abnormal Sharpe ratios were computed on the sample basis of 30 Dow Jones Industrial Average (DJIA) stocks. The computations allowed me to determine the optimal trading frequencies for the MA MOM strategy. The key result was that the MA MOM strategy could improve the MOM strategy on average by 0.16% per month. The optimal trading frequency for the MA MOM strategy with $5,000 was tri yearly through which (0.90 - 1.85 %) net monthly return could be achieved. The MOM strategy can be adjusted by a simple moving average (SMA) indicator on a 6 versus 36-month basis as a recommendation. This study might contribute to positive social change by adjusting the MOM strategy, which specifically impacts private investors in declining stock markets to improve the overall performance when trading the MA MOM strategy.

In environmental studies, measurements of interest are often taken on multiple variables. The results of spatial data analyses can be substantially affected by the spatial configuration of the sites where measurements are taken. Hence, optimal designs which result in data guaranteeing efficient statistical inferences need to be studied. We study optimal designs on two large classes of spatial regions with respect to three design criteria, which were prediction, covariance parameter estimation, and empirical prediction. The first class of regions includes those in the plane, where Euclidean distance is used. The performance of the optimal designs is compared to that of randomly chosen designs. Optimal designs for a small example and a relatively large example are obtained. For the small example, complete enumeration of all possible designs is computationally feasible. For the large example, the computational difficulty in searching for the optimal spatial sampling design is overcome by a simulated annealing algorithm. The second class of spatial regions includes streams and rivers, where the distance is defined as distance along the stream network. A moving average construction is used to establish valid covariance and cross-covariance models using stream distance. Optimal designs for small and large examples are obtained. An application of our methodology to a real stream network is included. We discuss the impact of asymmetry in the cross covariance function on the spatial multivariate design. The relationship between multivariate optimal design and univariate optimal design if the multivariate design is restricted to be completely collocated is studied. The efficiency lost if we consider the design that is optimal within the class of collocated designs is discussed.

One outstanding challenge to understanding the behaviors of organisms and other complexities found in nature through the use of computational fluid dynamics simulations lies in the ability to accurately model the highly tortuous geometries and motions they generally exhibit. Descriptions must be created in a manner that is amenable to definition within some operative computational domain, while at the same time remaining fidelitous to the essence of what is desired to be understood. Typically models are created using functional approximations, so that complex objects are reduced to mathematically tractable representations. Such reductions can certainly lead to a great deal of insight, revealing trends by assigning parameterized motions and tracking their influence on a virtual surrounding environment. However, simplicity sometimes comes at the expense of fidelity; pared down to such a degree, simplified geometries evolving in prescribed fashions may fail to identify some of the essential physical mechanisms that make studying a system interesting to begin with. In this thesis, and alternative route to modeling complex geometries and behaviors is offered, basing its methodology on the coupling of image analysis and level set treatments. First a semi-Lagrangian method is explored, whereby images are utilized as a means for creating a set of surface points that describe a moving object. Later, points are dispensed with altogether, giving in the end a fully Eulerian representation of complex moving geometries that requires no surface meshing and that translates imaged objects directly to level sets without unnecessary tedium. The final framework outlined here represents a completely novel approach to modeling that combines image denoising, segmentation, optical flow, and morphing with level set- based embedded sharp interface methods to produce models that would be difficult to generate any other way.

Nesse trabalho, estudamos o método do referencial móvel e sistemas diferenciais exteriores. Estabelecemos resultados de Geometria Riemanniana via referenciais móveis e com essa linguagem introduzimos o Teorema de Gauss-Bonnet-Chern e apresentamos uma adaptação da demonstração original de S.-S. Chern presente no artigo A simple intrinsic proof of the Gauss-Bonnet formula for closed Riemannian manifolds. Ao abordar aspectos da teoria de Cartan-Kähler, codificamos as ideias oriundas dos referenciais móveis em sistemas diferenciais exteriores e mostramos algumas aplicações à Geometria Riemanniana. / In this work, we study the method of moving frame and exterior differential systems. We set up results of Riemannian Geometry via moving frames and with this language we introduce the Gauss-Bonnet-Chern Theorem and present an adaptation of the original proof of S.-S. Chern in the article A simple intrinsic proof of the Gauss-Bonnet formula for closed Riemannian manifolds. In discussing aspects of Cartan-Kählers theory, we encode the ideas from moving frames into exterior differential systems and use this tool in Riemannian Geometry.

This dissertation explores the physics of droplet impingement on superhydrophobic surfaces. The research is divided in three categories. First, the effect of a slip boundary condition on droplet spreading/retracting is considered. A model is developed based on energy conservation to evaluate spreading rates on surfaces exhibiting isotropic and anisotropic slip. The results show that larger slip causes the droplet to spread out farther owing to reduced friction at the interface for both slip scenarios. Furthermore, effects of slip become magnified for large Weber numbers due to the larger solid-liquid contact area during the process. On surfaces with anisotropic slip, droplets adopt an elliptical shape following the azimuthal contour of the slip on the surface. It is common for liquid to penetrate into the cavities at the superhydrophobic interface following droplet impact. Once penetrated, the flow is said to be in the Wenzel state and many superhydrophobic advantages, such as self-cleaning and drag-reduction, become negated. Transition from the Wenzel to the Cassie state (liquid resides above the texture) is referred to as dewetting and is the focus of the second piece of this dissertation. Micro-pillar pitch, height and temperature play a role on dewetting dynamics. The results show that dewetting rates increase with increasing pillar height and increasing surface temperature. A scaling model is constructed to obtain an explanation for the experimental observations and suggests that increasing pillar height increasing the driving dewetting force, while increasing surface temperature decreases dissipation. The last piece of work of this dissertation entails droplet impingement on superheated surfaces (100°C - 400°C). We find that the Leidenfrost point (LFP) occurs at a lower temperature on a hydrophobic surface than a hydrophilic one, where the LFP refers to the lowest temperature at which secondary atomization ceases to occur. This behavior is attributed to the manner in which vapor bubbles grow at the solid-liquid interface. Also in this work, high-speed photographs reveal that secondary atomization can be significantly suppressed on a superhydrophobic surface owing to the micro-pillar forest which allows vapor to escape hence minimizing bubble formation within the droplet. However, a more in-depth study into different superhydrophobic texture patterns later reveals that atomization intensity can significantly increase for small pitch values given the obstruction to vapor flow presented by the increased frequency of the pillars.

The expanding potential for the dissemination and archiving of aphorisms is explored in this practice-based research thesis. An aphorism is a short statement that communicates an insight about the world (and can sometimes function as a guide to action). Eric McLuhan, interviewed in Signs of the Times: The History of Writing (Goëss Video, 1996), suggests that the future of the book is the aphoristic statement. Aphoristic knowledge has traditionally been transmitted through texts and through libraries, but this project brings into play various modes of recirculating aphoristic texts using contemporary distribution networks and digital media such as moving image, projection on to urban screens, artists’ books, archival digital photography and glazed ceramics. Texts ‘virally inhabit’ a number of sites and languages in a series of works situated in the interdisciplinary context of contemporary text art and artists’ books. The sayings rejoin the cultural river of ideas in local and international incarnations. Practice-based work (80%) and exegesis (20%)

Doctor of Education / With the heightened profile of language learning in a global community, language education is exploring a new model of intercultural language learning. The goal of intercultural language learning is to produce language users equipped with explicit skills in understanding connections and differences between their own culture and the culture of the target language. The research literature suggests that language learners’ resulting intercultural competence will encompass a range of characteristics. There have been few empirical studies, however, to provide illustration of intercultural competence, in order to assist teachers’ understanding of desired outcomes and student development. This case study investigates the characteristics of intercultural competence in young language learners in one Australian primary school. The learners have been engaged in an immersion language program for up to eight years, in one of three languages: French, German or Japanese. The study also investigates the behaviours and understandings in their language teachers which may facilitate the development of learners’ intercultural competence. It explores in summary what may be the nature of intercultural competence in the case study language learners. The study is relevant to research of both intercultural language learning and of immersion language classrooms. Using a case study design, the study incorporates qualitative data in the form of student focus group interviews, teacher interviews, and classroom observations. Data were collected at the case study school, in Sydney, Australia, over a school semester, and involved 49 Year 6 students and four teachers. Results of the study suggest a number of indicators of the case study students’ development in intercultural competence – that is, through understanding of language culture and identity. The student is and sees him or herself as a purposeful interactive communicator. The student understands the target language itself to be the vehicle of the target culture, and often displays metalinguistic curiosity and skills. Some students are able to critically reflect on their (multiple) linguistic and cultural memberships, and to negotiate their identity as a non-native language user. The study found that teachers provide a model of interculturality to their students. The teachers’ interculturality is enacted in their relationships and pedagogical choices, in their design of experiential learning tasks, and their facilitation of linguistic and cultural connections for their students. The study also found that the nature of the immersion language classroom itself facilitates intercultural competence in students. The study provides a case study illustration of intercultural competence in language learners which is relevant to research in intercultural language learning, immersion pedagogy and the emerging related pedagogy of content-based language learning.

Master of Science/Doctor of Clinical Psychology / Figures from the Australian Bureau of Statistics show that over 40% of all Australian children moved at least one time in the census period from 1996 to 2001 (ABS, 2001). The literature varies in the impact that this has on children. The purpose of this study was to examine the associations between residential relocation, resilience and the emotional, behavioural and academic adjustment of children 8-12 years of age who had moved. Risk factors as identified in the literature as well as the relative impact of resilience were examined. By studying how adjustment occurs in the context of resilience, possible areas for prevention and intervention may be developed for the large numbers of children who move. Results showed that the sample population was in the normal range in academic and behavioural terms. The sample was found to have repeated more grades than average; however the children did not exhibit significant behavioural or emotional consequences. A number of demographic factors have been indicated in the literature as affecting adjustment after residential relocations, yet these were generally not found to be significantly associated with adjustment for this study population. Socioeconomic status was the only factor other than resilience to have been significantly associated with adjustment. Possibly due to the developmental stage of the participants, only the resilience subscales of interpersonal strength and school functioning were found to be significant in their positive association with adjustment, leading to fewer behavioural and academic problems. While the children in this study have all had the potential stress of moving house, the demographic characteristics of this sample would suggest that they might not have had to encounter multiple life challenges or adversities. This conclusion may help explain the lack of significant effects of demographic factors on the adjustment of the children in this sample. Results highlight the importance of good schooling and that the core business of schools in building and enhancing the intellectual functioning of children, is a vital component in the development of resilience. These findings suggest that different aspects of resilience may be important for different developmental stages and different life stressors. The distinction between cause and effect when examining resilience factors is discussed and it is suggested that outcomes in one context may be treated as influences upon outcomes in another context.

The purpose of this study was to identify and examine risk and protective factors associated with residential instability within a sample of rural low-income mothers. Residential instability was defined as two or more residential moves within the course of a year. Qualitative and quantitative methods were used to compare residentially stable and residentially unstable participants in order to isolate the factors that differentiated the two groups. These factors were analyzed through life course and ecological theoretical perspectives. Significant factors associated with residential instability included childhood and adulthood contexts, as well as changes in family structures throughout the life course. Based on the findings from this sample, it could be conservatively estimated that 10 to 25% of rural low-income families with children were residentially unstable between 2000 and 2001. Previous research has pointed to the severe negative educational, social, and developmental impacts of residential instability on children. Findings from this study suggest that the children who are most at risk for future residential instability in any given year are likely to have experienced residential instability already, compounding the impact of residential instability on these children. This study also supports the previous finding that residential instability is transmitted across generations, with childhood residential instability predictive of residential instability in adulthood. Participants who had moved frequently during childhood were significantly more likely to be residentially unstable, as were participants who had been homeless within the two years previous to being surveyed. Participants who were sharing housing with relatives were also at risk of residential instability, due to strain on relationships between participants' families and the relatives with whom they were sharing housing. Relationship strain associated with residential instability also occurred between participants and their partners, with partnership separation significantly predictive of residential instability. Many residentially unstable participants went through cycles of moving in and out of relatives' and/or partners households, moving in and out with partners, or both. The connection between previous residential instability and subsequent residential instability was theorized to be associated with persistent poverty, and may also have indicated other destabilizing conditions. Difficulty in maintaining relationships or holding down a job, mental health problems, poor survival skills, or patterns of bad choices were all destabilizing conditions that could theoretically lead to residential instability. These destabilizing conditions may have often been associated with persistent poverty and their consequences may have been amplified by persistent poverty. / Graduation date: 2005

The purpose of this study was to determine what levels of community satisfaction and personal and household characteristics would result in a model of retirees and pre-retirees and their propensity to move. This study assessed the relationship between certain socio-demographic variables and feelings of overall satisfaction as well as satisfaction with specific aspects of their current community. Community size and tenure, preferred community size, and the preference of staying or moving were also explored. Satisfaction was measured by both a global question of satisfaction and through the construction of a Community Satisfaction Scale (CSS) and three subscales. A hypothesized model was tested using logistic regression. Age, gender, duration in community, agreement between current and preferred community size (metropolitan or nonmetropolitan), overall satisfaction, and satisfaction with quality of life factors in the community and environmental quality were statistically significant in the prediction of likelihood of moving at retirement. Variables, some of which were significantly related to the dependent variable in preliminary analyses (chi-square and t-tests), that were not found to be significant in the logistic regression model of the propensity to move were: education, marital status, employment, household size, health, previous moving experiences, and the subscale community safety. Three measures of personal and household economic resources were also not found to be significant. According to final model in this study, in the sample of 50 to 70 years in Idaho, Nevada, and Wyoming, those who were younger, had lived in the community fewer years, were living in a community size not in agreement with the stated size of community they preferred, and were male were more likely to response a preference to move. The results indicate small-urban and semi-rural communities are the most preferred places to move. The open areas outside the incorporated towns and cities were most favored locations. A benefit of elderly migration research in the past, discussed at length in the review of the literature, is that retirees bring with them to the community the benefits described as the "mail box economy." Understanding the levels of satisfaction of current residents ages 50 to 70 may be as important as policies to attract new inmigrants. / Graduation date: 1995