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This study compared middle school (i.e., fifth, sixth and seventh grade) students’ mental models of the day/night cycle before and after implementation of three inquiry-based treatments. The three treatments were classified as 1) structured inquiry, 2) guided inquiry, and 3) student-directed inquiry. All three treatments used Starry Night Middle School interactive simulation software to investigate the phenomenon of the day/night cycle. Additionally, all three treatments were based on two researcher-developed lessons using Starry Night Middle School. The participants were 145 fifth, sixth, and seventh grade students who were purposively selected from a public school in a U.S. state. For the purpose of this study, the students remained in their classrooms. There were three classrooms per grade level. Those classrooms were randomly assigned to one of the three treatments. Students’ scores on a pretest, immediate posttest, and delayed posttest were analyzed. Students from a purposive sample were interviewed after the pretest, immediate posttest, and delayed posttest to clarify student mental models of the day/night cycle. The students were chosen based upon their score on the multiple-choice test. Seven of the selected students were in the Structured Inquiry group. Eleven of the selected students were in the Guided Inquiry group. Five of the selected students were in the Student-directed Inquiry group. First, the comparative effects of Structured Inquiry, Guided Inquiry, and Student-directed Inquiry on middle school students’ mental models of the day/night cycle immediately and three months following the intervention revealed no statistical difference among the three treatments. Time, however, appeared to have a significant negative effect on students’ mental models of the day/night cycle. Second, inquiry groups did not differ significantly in their mental models. Third, there was no interaction between starting mental model and the type of inquiry. The major findings demonstrate that all three treatments promote learning, but that no one treatment is more effective than another.

This thesis evaluates a hypothesis about how to implement a low cost Differential GPS (DGPS) solution, able to find a current location with a precision almost as good as more expensive DGPS solution.  For this purpose two Smartphone’s are used, one used as a fixed reference station and another used as a roving receiver. The reference station calculates the temporary error at its location at every second and transmits these errors to a server over the internet.  The roving receiver requests to the server to get the latest error from the reference station over the internet. By using these errors or differences, the roving receiver finds a corrected location. The results are in the same range as dedicated DGPS solutions.

The recovery of generic solid parts is a fundamental step towards the realization of general-purpose vision systems. This thesis investigates issues in grouping, segmentation and recognition of parts from two-dimensional edge images. A new paradigm of part-based grouping of features is introduced that bridges the classical grouping and model-based approaches with the purpose of directly recovering parts from real images, and part-like models are used that both yield low theoretical complexity and reliably recover part-plausible groups of features. The part-like models used are statistical point distribution models, whose training set is built using random deformable superellipse. The computational approach that is proposed to perform model-guided part-based grouping consists of four distinct stages. In the first stage, codons, contour portions of similar curvature, are extracted from the raw edge image. They are considered to be indivisible image features because they have the desirable property of belonging either to single parts or joints. In the second stage, small seed groups (currently pairs, but further extension are proposed) of codons are found that give enough structural information for part hypotheses to be created. The third stage consists in initialising and pre-shaping the models to all the seed groups and then performing a full fitting to a large neighbourhood of the pre-shaped model. The concept of pre-shaping to a few significant features is a relatively new concept in deformable model fitting that has helped to dramatically increase robustness. The initialisations of the part models to the seed groups is performed by the first direct least-square ellipse fitting algorithm, which has been jointly discovered during this research; a full theoretical proof of the method is provided. The last stage pertains to the global filtering of all the hypotheses generated by the previous stages according to the Minimum Description Length criterion: the small number of grouping hypotheses that survive this filtering stage are the most economical representation of the image in terms of the part-like models. The filtering is performed by the maximisation of a boolean quadratic function by a genetic algorithm, which has resulted in the best trade-off between speed and robustness. Finally, images of parts can have a pronounced 3D structure, with ends or sides clearly visible. In order to recover this important information, the part-based grouping method is extended by employing parametrically deformable aspects models which, starting from the initial position provided by the previous stages, are fitted to the raw image by simulated annealing. These models are inspired by deformable superquadrics but are built by geometric construction, which render them two order of magnitudes faster to generate than in previous works. A large number of experiments is provided that validate the approach and, since several new issues have been opened by it, some future work is proposed.

This thesis is the formulation of a theological response to the modern economic market. It argues for a Two Pillars paradigm for the economic market, whereby covenant and contract serve together as the two “pillars” that uphold economic order. The modern market is derived and developed upon the legal contract that supports and governs economic activities. Non-contractible assertions in the market remain background presuppositions, of which enactment depends largely on the individual economic agent. In the Two Pillars paradigm, I argue that the theological covenant and the legal contract are equally significant assertions that interact and complement each other to uphold a well-balanced economic market. They are both essential in deriving a market that promotes genuine human relationship, freedom and economic justice. In this study, the covenant foundation of society and its economic significance are rediscovered and examined. The universality and relevance of the covenant concept for economic order is explored, and the covenant compared and contrasted with the contract to show their distinctiveness, significance and interaction in the market. The Two Pillars paradigm is then presented and illustrated through the example of long-term employment arrangements to demonstrate its practicability and potential use as a dialogical framework to examine other economic relationships. Finally, market fundamentals including market motif, limits, assumptions, morality and regulations are explored in dialogue with the Two Pillars response to economics. This study should appeal to a wider audience beyond the ecclesiastical community, placing it in the arena of public theology. It draws upon the thoughts of economists to examine the Two Pillars paradigm in a wider context. The result is an interdisciplinary study offering a theological-based paradigm that addresses the situation of the modern market in a fundamental and practical way.

This thesis reports research undertaken in two rather distinct phases. Firstly, the thesis reports a study of cognitive processes involved in the task of 'concept identification': given sample instances of a concept, the task is to identify the concept. A computer model which successfully reproduces responses similar to those observed in human subjects is described. Secondly, this thesis reports the design of a case-based learning system REFINER. The system is a 'Learning Apprentice System' for differential diagnosis tasks, to aid the transfer of knowledge from a domain expert to a computer. Knowledge is obtained from the expert(s) in the form of cases which have been diagnosed or classified, and not in the traditional form of classification 'rules' which the experts often find hard to specify. The REFINER program is therefore a Knowledge Acquisiton System which helps an expert refine his knowledge in a more 'natural' way than having rules 'extracted'. Further, the system has the ability to point out that two classifications are not distinct, and can then suggest to the user ways in which the inconsistency might be resolved. Although the system has been used most extensively in the medical domain, it is essentially domain independent.

This research uses observation, interviews and content analysis to examine the perceived and actual risks arising from Internet use in eight educational establishments. The majority of staff interviewed expressed concern about online pornography and the dangers of web based chat rooms. Additionally staff were anxious about the risks posed by hate engendering sites, websites encouraging experimentation, copyright infringement and threats to network security. In considering these school Internet risk narratives I make a distinction between concern that the student is "at risk" and that they are "dangerous”, posing a threat to the institution. I point out that in the primary schools staff talked about students solely as being "at risk", whereas in secondary schools this concern was tempered with the view that students misusing the school Internet also posed a danger to the institution. In the post-16 college Internet risks were almost solely expressed in terms of the "dangerous student". While only a sparse student risk narrative existed, with a few students anxious about on-line pornography, chat-lines and security there was non-verbal evidence indicating that students were worried about being punished for misusing the Internet. In assessing the "student- at-risk", I argue that exposure to pornography via the school Internet was not likely to pose an actual risk, while undesirable others in chat rooms, hateful websites and sites encouraging experimentation all posed actual, though statistically remote, risks. Considering the Internet activities of the "dangerous student", I found little evidence to suggest that the issues of school image, staff authority and copyright should be a source of great concern, although I note that school network security was an actual risk which deserves more attention. Finally, I consider institutional attempts to control Internet use and alleviate some of these perceived and actual risks through the use of rhetoric, exclusion and surveillance.

D.Litt. et Phil. / Jean Piaget (1896-1980) played a major role in laying the groundwork for many of our current beliefs about cognitive development. While specific beliefs and ideas of different cultures may vary, Piaget posited that the stages of cognitive development, namely, sensori-motor, pre-operational, concrete operational and formal operational, unfold in the same sequence at roughly the same ages, irrespective of cultural and educational background. The new political changes in South Africa have transformed the education policies from the content-orientated, rote-learning based curriculum of the past, to a skills-based, interactive learning approach called Outcomes-Based Education (OBE). OBE aims to move away from the old ¡¥tabula rasa¡¦ education policy towards a dynamic learning system that involves learners at a critical level of intelligence. OBE presents itself as compatible with developments in cognitive psychology, particularly Piaget¡¦s theory of intellectual development. With the recent change in curriculum, this research investigated whether children in South Africa have attained concrete and formal operations as OBE purports to encourage. The research takes a closer look at children¡¦s cognitive abilities as assessed by Piaget¡¦s theory of development. With reference to South African education ¡§as part of the far-reaching political, social and economic changes, aimed at an egalitarian and healthy society, the new political dispensation has replaced the previous education policy with a constructivist, Outcomes Based Educational approach.¡¨ (Skuy et al, 1999, p. 3). This study was conducted on children from grades one through to grades five, at two primary schools. One of the schools implemented OBE „b 4 years ago (experimental group), whilst the other has not as yet implemented OBE (control group). The measuring instruments consisted of Piaget¡¦s cognitive tests for assessing the concrete and formal operational stages. Piaget¡¦s tests are designed to look for a particular type of understanding/reasoning that typifies a particular developmental stage (Bybee & Sund, 1982). The tests consisted of one-to-one interviews designed to evaluate concrete, transitional and formal operational patterns of thought. Due to the relatively small sample group (ten participants per group) and the fact that the data is ordinal, the analysis was carried out using non-parametric and descriptive statistics. Thus, the results of Piaget¡¦s tests were compared to OBE related marks and academic marks using Spearman¡¦s Correlation Coefficient for ranked data, in order to better understand the nature of the relationship between OBE and cognitive development. Since the data is categorical, i.e., categorised as concrete operational and formal operational, the results of each child in the OBE school were also compared to the results of each child in the non-OBE school using the Mann-Whitney-U test (Howell, 1995) in order to determine whether there is a difference between OBE-cognitive development and Non-OBE-cognitive development. The aim of this study was to establish whether O.B.E is indeed a better approach than other methods of teaching with reference to cognitive development. The conclusion that can be drawn from this study is that O.B.E is not necessarily a more superior system to that of other teaching systems, and that in fact, the more traditional methods of teaching may enhance cognitive development more than O.B.E. / Dr. Alban Burke