No description available.

The term biological motion has been coined by G. Johansson (1973) to refer to the ambulatory patterns of terrestrial bipeds and quadripeds. In this paper a computational theory of the visual perception of biological motion is proposed. The specific problem addressed is how the three dimensional structure and motions of animal limbs may be computed from the two dimensional motions of their projected images. It is noted that the limbs of animals typically do not move arbitrarily during ambulation. Rather, for anatomical reasons, they typically move in single planes for extended periods of time. This simple anatomical constraint is exploited as the basis for utilizing a "planarity assumption" in the interpretation of biological motion. The analysis proposed is: (1) divide the image into groups of two or three elements each; (2) test each group for pairwise-rigid planar motion; (3) combine the results from (2). Fundamental to the analysis are two 'structure from planar motion' propositions. The first states that the structure and motion of two points rigidly linked and rotating in a plane is recoverable from three orthographic projections. The second states that the structure and motion of three points forming two hinged rods constrained to move in a plane is recoverable from two orthographic projections. The psychological relevance of the analysis and possible interactions with top down recognition processes are discussed.

Phylogenetics is a field primarily concerned with the reconstruction of the evolutionary history of present day species. Evolutionary history is often modeled by a phylogenetic tree, similar to a family tree. To recreate a phylogenetic tree from information about current species, one needs to make assumptions about the evolutionary process. These assumptions can range from full parametrised models of evolution to simple observations. This thesis looks at the reconstruction of phylogenetic trees under two different assumptions. The first, known as the ordinal assumption, has been previously studied and asserts that as species evolve, they become more dissimilar. The second, the convex assumption, has not previously been studied in this context and asserts that changes species go through to become dissimilar are progressively larger than the current differences between those species. This thesis presents an overview of mathematical results in tree reconstruction from dissimilarity maps (also known as distance matrices) and develops techniques for reasoning about the ordinal and convex assumptions. In particular, three main results are presented: a complete classification of phylogenetic trees with four leaves under the ordinal assumption; a partial classification of phylogenetic trees with four leaves under the convex assumption; and, an independent proof of a result on the relationship between ultrametrics and the ordinal assumption.

Obesity and being overweight have become growing concerns due to their association with many diseases, such as type II diabetes, several types of cancer and heart disease. Thus, obesity treatments have been the focus of a large number of recent studies. Because of these studies, researchers have found that the treatment of obesity and being overweight requires constant monitoring of the patient’s diet. Therefore, measuring food intake each day is considered an important step in the success of a healthy diet. Measuring daily food consumption for obese patients is one of the challenges in obesity management studies. Countless recent studies have suggested that using technology like smartphones may enhance the under-reporting issue in dietary intake consumption. In this thesis, we propose a Food Recognition System (FRS) for calories and nutrient values assumption. The user employs the built-in camera of the smartphone to take a picture of any food before and after eating. The system then processes and classifies the images to detect the type of food and portion size, then uses the information to estimate the number of calories in the food. The estimation and calculation of the food volume and amount of calories in the image is an essential step in our system. Via special approaches, the FRS can estimate the food volume and the existing calories with a high level of accuracy. Our experiment shows high reliability and accuracy of this approach, with less than 15% error.

Obesity and being overweight have become growing concerns due to their association with many diseases, such as type II diabetes, several types of cancer and heart disease. Thus, obesity treatments have been the focus of a large number of recent studies. Because of these studies, researchers have found that the treatment of obesity and being overweight requires constant monitoring of the patient’s diet. Therefore, measuring food intake each day is considered an important step in the success of a healthy diet. Measuring daily food consumption for obese patients is one of the challenges in obesity management studies. Countless recent studies have suggested that using technology like smartphones may enhance the under-reporting issue in dietary intake consumption. In this thesis, we propose a Food Recognition System (FRS) for calories and nutrient values assumption. The user employs the built-in camera of the smartphone to take a picture of any food before and after eating. The system then processes and classifies the images to detect the type of food and portion size, then uses the information to estimate the number of calories in the food. The estimation and calculation of the food volume and amount of calories in the image is an essential step in our system. Via special approaches, the FRS can estimate the food volume and the existing calories with a high level of accuracy. Our experiment shows high reliability and accuracy of this approach, with less than 15% error.

The notion of ‘pattern’ originates in the work of Christopher Alexander and, in recent years, patterns have become a popular part of software development. A pattern is defined as a ‘three-part rule’: a relationship between a given context, a recurring system of forces peculiar to that context, and a specific spatial configuration that permits resolution of these forces. In essence, the ‘context’ of a pattern is the whole system under construction and its state in the construction process at the point at which the pattern is being applied. The nature of the context, therefore, changes at every step of the process and this has significant implications for how patterns should be used. Specifically, applying each pattern changes the context by changing the state of the system under construction and creates both a new design problem and a new context for the next pattern to be applied. The next picked pattern must have a certain criteria in order for it to be applied successfully and this is will be determined by the characteristics of the new context just created. The issue of composing pattern sequences is therefore more temporal than it is static and structural (as provided currently via pattern maps). The decision as to which one to use is temporally constrained in the sense that the choice is made only at a particular point in the construction process of some specific system, and may well be determined, or at least further constrained, by the current state of that system. The fundamental research question that is addressed here is: how is this dynamically changing context to be presented to guide pattern applications? In this thesis, a framework is presented to provide a systematic analysis of composition of pattern applications in terms of the properties of their context. Such an approach will reveal the ordering of patterns in space and time dimensions. Examples of composition of pattern applications include: - One pattern contains or generalises another smaller-scale pattern (this will be called in thesis refinement); - Two patterns are complementary, i.e., one pattern needs the other to be applied before (Sequential Order); - Two patterns solve different problems that overlap and coexist on the same level (Parallel Order); - Two patterns solve the same problem in alternative, but equally valid ways (Choice in Order). At the design phase, the framework provides mechanisms for analysing the choice of composition to ensure the correctness of a design or to compare between two different designs or to modify an existing design. This framework describes a pattern's context via a pair of constraints, known as Assumption and Commitment. In general, the Assumption is a constraint placed on the context and the Commitment is what the solution provided by the pattern commits to after the pattern's application. In addition, the thesis provides a set of composition rules that can be applied to aid in the analysis of the application of pattern sequences. The approach is domain independent as it does not depend on the nature of the catalogue from which the patterns originate. The work has been evaluated using various existing patterns from Ian Graham’s web usability (WU) pattern bank and the User Interface (UI) patterns of Welie.

The problem of this study was an investigation of some dimensions of leadership behavior of Texas school superintendents as perceived by themselves and as perceived by their staffs.

The Clean Water Act's §404 allows states to assume control of wetland dredge-and-fill permitting from the Federal Government. However, since the bill was passed in the 1970's, only two states have successfully assumed control of the permitting program. Each state that has looked into assumption has run into barriers, issues, and problems that have prevented them from successfully assuming the program. I interviewed people involved with assumption at different levels of involvement, and this thesis seeks to provide a conflict management design system that will help states overcome some of the most pernicious issues.

Magister Legum - LLM / The fragmented approach of provinces in the use of legislation and policies, coupled with the uncertainty of key terms in the context of section 139(1) of the Constitution, have resulted in provincial executives not being consistent or not always complying with the use of the steps necessary for interventions in terms of section 139(1) of the Constitution. In order to assess the impact of the fragmented approach and uncertainties on how provincial executives apply the above mentioned steps, this study answers eight questions designed to test the way in which provincial executives applied the aforementioned steps and the effectiveness of the use of aforementioned interventions. The assessment is based on the tallies from the answers to the eight questions, and the grouping of these answers in accordance with the tallies. Each of the three main groups characterises how the relevant provincial executives applied the steps necessary for the use of interventions in terms of section 139(1) of the Constitution for the last five years. The fourth group assesses the effectiveness of such interventions. The answers are derived from the data relating to the notices to the Minister and NCOP, and complemented by the progress reports from the Minister and NCOP. The findings of the four groupings are as follows: the first group presented the steps which present no difficulty in terms of compliance; the second group presented the steps which provincial executives mostly complied with but which at times present some difficulty; and the third group presented those steps which are problematic. The fourth group determined that the effectiveness of the role of provinces in the use of interventions in terms of section 139(1) of the Constitution is questionable due to the repetition and duration of a number of interventions. In order to address the issue of non-compliance by provincial executives with the steps necessary for the use of interventions, the study recommends the drafting of legislation and formulation of clear policy guidelines which will ensure a consistent, coherent and uniform approach when invoking interventions.

An observer’s inference that multimodal signals come from a common underlying source can facilitate cross-modal binding in the temporal domain. This ‘unity assumption’ can cause asynchronous audiovisual speech streams to seem simultaneous (Vatakis & Spence, 2007), but follow-up work has been unable to replicate this effect for non-speech, musical events (Vatakis & Spence, 2008). Given that amplitude envelope (the changes in energy of a sound over time) has been shown to affect audiovisual integration, the current study investigates whether previous null findings with musical stimuli can be explained by the similarity in amplitude envelope between audiovisual conditions. To test whether amplitude envelope affects temporal cross-modal binding, Experiment 1 contrasted events with clearly differentiated envelopes: cello and marimba audiovisual stimuli. Participants performed an un-speeded temporal order judgments task; they viewed audio-visually matched (e.g. marimba auditory with marimba video) and mismatched (e.g. cello auditory with marimba video) versions of stimuli at various stimulus onset asynchronies and indicated which modality was presented first. As predicted, participants were less sensitive to temporal order (greater JNDs) in matched conditions, suggesting that the unity assumption facilitates synchrony perception outside of non-speech stimuli. Results from Experiments 2 and 3 revealed that when spectral information was removed, amplitude envelope alone could not facilitate the influence of audiovisual unity on temporal binding. We propose that both amplitude and spectral cues affect the percept of audiovisual ‘unity’, likely working in concert to help an observer determine the causal source of an auditory event. / Thesis / Master of Science (MSc)