Considerable research has examined strategies involved in spatial navigation, and what factors determine which strategy an individual will use. The little research that has examined strategy adoption has produced conflicting results. The present study investigated the relative rate of adoption of allocentric and egocentric strategies in an environment that allowed individuals to adopt one or the other, or switch between them. Results indicated that by the end of testing nearly all participants had adopted one strategy or the other. Also, more participants were using an allocentric strategy than an egocentric strategy. However, strategy selection was not related to gender, or the relative efficiency of the two strategies. Analysis of gaze position at the start of trials showed that those who adopted an allocentric strategy tended to focus their attention on the distal (landscape) features of the environment whereas those who adopted an egocentric strategy tended to focus their attention on the proximal object features. However, vertical gaze position could not be used to reveal the rate of adoption of an egocentric strategy, because this did not vary over trials. Analysis of gaze position using “regions of interest” overcame this problem and showed that both strategies are adopted at a similar rate early in trials. Comparison of strategy by gaze position and strategy by navigation probe indicated that these two metrics were measuring two different stages of navigation. Finally, analysis of the navigational efficiency of different strategies indicated that the best navigators were those who used both strategies. These findings indicate allocentric and egocentric strategies are adopted at a similar rate and that within the space of a few seconds, individuals may use different strategies for orientation and navigation. / Graduate

Um novo modelo para a especificação de hiperdocumentos denominado HMBS - Hyperdocument Model Based on Statecharts - é proposto. O HMBS adota como modelo formal subjacente a técnica Statecharts, cuja estrutura e semântica operacional são utilizadas para especificar a estrutura organizacional e a semântica de navegação de hiperdocumentos grandes e complexos. A definição do HMBS, bem como a semântica de navegação adotada, são apresentadas. Na definição apresenta-se como o modelo permite separar as informações referentes a estrutura organizacional e navegacional das representações físicas do hiperdocumento. Também são discutidas características do modelo que possibilitam ao autor analisar a estrutura do hiperdocumento, encorajando a especificação de hiperdocumentos estruturados. Para provar e validar a viabilidade prática do uso do HMBS num contexto real foi desenvolvido um ambiente de autoria e navegação de hiperdocumentos denominado HySCharts - Hyperdocumenf System based on Statecharts. Esse ambiente fornece facilidades de prototipação rápida e simulação interativa de hiperdocumentos. Para ilustrar como o modelo HMBS e o HySCharts podem ser utilizados no contexto de uma abordagem de projeto sistemática é utilizada como estudo de caso a especificação de um hiperdocumento que apresenta o Parque Ecológico de São Carlos / A new model for hyperdocument specification called HMBS - Hyperdocument Model Based on Statecharts - is proposed. HMBS uses the Statechart formalism as its underlying model. Statecharts structure and operational semantics are used to specify the organizational structure and the browsing semantics of large and complex hyperdocuments. The definition of HMBS is presented and its browsing semantics is described. It is shown how the model allows the separation of information related to the organizational and navigational structure from the hyperdocument\'s physical representation. Model features that allow authors to analyze the hyperdocument structure, encouraging the specification of structured hyperdocuments are also discussed. As a proof of concept and also to evaluate the feasibility of using HMBS in real-life applications a system called HySCharts - Hyperdocument System based on StateCharts - was developed. HySCharts is composed by an authoring and a browsing environments, supporting rapid prototyping and interactive simulation of hyperdocuments. A case study is presented that uses the specification of a hyperdocument introducing the Ecological Park of São Carlos to illustrate the use of HMBS and of the HySCharts environment integrated into a systematic design approach

Global Navigational Satellite Systems (GNNS,) of which the Global Positioning System (GPS) of the United States is the most widely used, is increasingly being used by the South African National Defence Force (SANDF) for navigation and positional data. However, the SANDF can only use civilian type GPS receivers, which make use of the Standard Positioning Serves (SPS) and not the encrypted Precise Positioning Service (PPS), which is only available to the United States military forces and its allies. The aim of this work is to understand the influences that impact on the use of a GPS and specifically the capabilities of civilian type GPS receivers. The first objective will be to propose and motivate the use of a standardised reference frame that can be used by the SANDF for positional data in general and for GPS measurements specifically. In this regard it is proposed that the SANDF standardises on the World Geodetic System 1984 (WGS 84) as the standard ellipsoid and also use it as a universal horizontal datum for mapping projects. For survey tasks WGS 84 can be used in combination with a selected International Terrestrial Reference Frame (ITRF) epoch for reference stations. The International GNNS Service (IGS) stations can be used as such reference stations; the geometric distribution can be improved as the African Reference Frame (AFREF) add more stations to the existing IGS network. In the absence of a common vertical datum it is suggested that the Earth Gravitational Model 2008 (EGM 2008) be used. Secondly, the use of GPS for positional data should be aligned with the required positional accuracy requirements and standards of the SANDF. In this regard it is suggested that international positional accuracy standards are accepted and implemented to ensure interoperability. The third objective is to describe and understand how to mitigate influences that impact on the reliability of GPS. This is specifically important with the use of low accuracy civilian type GPS receivers for navigation and the collection of ground control for mapping projects. The fourth objective will be to establish with practical field trials the effect of these influences on GPS measurements and device appropriate data collection strategies. One serious impact is the susceptibility of civilian GPS receivers to jamming. This is addressed but not sufficiently to formulate policy and would require further investigation. There is a worldwide drive to make GPS reliable for safety of life applications such as air and rail transport which also benefits its use for military applications. It is therefore important for the SANDF users to know and understand these influences on GPS in order to optimise its use for operations. Copyright / Dissertation (MSc)--University of Pretoria, 2012. / Geography, Geoinformatics and Meteorology / MSc / Unrestricted

Using search to navigate an application could sometimes be a more efficient way than browsing. This does however require the implementation of the search to be satisfactory for a user not to abandon it. This thesis focused on improving a keyword-only solution by studying how users construct navigational queries and implementing a new search that intelligently interprets the users' search and better understands the business application. Both search implementations were then evaluated by their ability to return the relevant page. The results showed that the new search modeled to the business application did manage to perform better with a higher retrieval success rate and more frequently returned the desired page closer to the first position in the result set.

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The purpose of my dissertation study is to better understand the educational experiences of undergraduate engineering students within non-curricular learning environments, specifically in the form of extracurricular engineering groups or programs. I first conducted a content analysis of engineering education literature to identify where engineering design learning occurs, and to synthesize the implications of studies regarding engineering design learning. Aiming to fill a gap in the literature regarding non-curricular learning contexts, this study investigated what extracurricular groups and programs can educationally provide undergraduate engineering students by observing and interviewing students engaging in these environments. This study also aimed to identify if and how engineering students find navigational flexibility within engineering curricula, and how non-curricular learning environments might provide navigational flexibility. With regard to where engineering design learning occurs, the literature points to various educational contexts that effectively deliver engineering design education. Strategies that involve authentic and longer-term engineering design experiences tend to be the most impactful in terms of student outcomes and perceptions, however those experiences are not always implementable at larger scale. More traditional educational approaches to engineering design learning, though less impactful, are still effective delivery methods for introducing key aspects of engineering design education (e.g. modeling, global/societal/economic/environmental factors, communication skills). However, there was limited literature regarding more non-curricular learning experiences, such as learning in designed settings, outreach learning, learning media, and everyday informal learning. This literature review is one of the first attempts towards synthesizing where and how engineering design learning occurs, and has identified a significant gap in the literature regarding non-curricular educational settings. Addressing the identified gap in engineering education literature regarding non-curricular learning experiences, this dissertation study investigated five non-curricular engineering learning sites for undergraduate engineering students at a large research-driven state institution. Informed by the preliminary findings of a pilot study, I first investigated the salient features of engineering-related non-curricular activities from the students' perspectives using a self-directed learner autonomy framework to guide the study. Students participating in extracurricular engineering environments exhibited strong attributes of self-directed learners, particularly a willingness and ability to be challenged and to learn. The educational environments of the extracurricular opportunities cultivated these self-directed learning attributes by providing students a space to be exposed to an engineering community, authentic engineering work, and accessible resources. Findings from this portion of the dissertation indicated necessary modifications to the self-directed learner autonomy framework used to guide this study. The modified framework contributes a possible approach towards future assessment or research pursuits regarding non-curricular learning experiences in engineering. I also investigated the role non-curricular activities play in providing engineering students navigational flexibility through engineering curricula. Extracurricular engineering environments afford navigational flexibility by offering students opportunities to work on motivating challenges with and among supportive communities. By providing a space for students to express their engineering selves in primarily self-directed ways, extracurricular engineering experiences cultivate students' drive to find and pursue personally meaningful curricular and non-curricular educational experiences. However, institutional barriers, particularly time constraints and institutionally recognized achievements, stifle students' flexibility and willingness to pursue personally meaningful experiences. The findings of this study have helped uncover the various affordances non-curricular learning experiences provide engineering students, but more importantly, have identified the institutional barriers that prevent students from taking full advantage of non-curricular learning experiences. Based on these findings, I recommend that university and program level structures be reevaluated to encourage and provide students with more flexibility to find personalized learning experiences in and out of the classroom. / Ph. D.

The purpose of this paper is to analyse which navigational rights are applicable to foreign commercial vessels performing trans-arctic shipping through the Northwest Passage and how this affects the potential for Canada, through article 234 of the United Nations Convention on the Law of the Sea (UNCLOS), to issue national environmental legislation regulating pollution from ships. This is done through the method of legal dogmatics, characterised by analysis of the sources of law and the hierarchy between them. In this paper, the main sources of law employed are UNCLOS and relevant case law from the International Court of Justice. The main conclusions presented in the paper are that the Northwest Passage consists of a combination of territorial sea and exclusive economic zone, which generally means that commercial vessels are allowed innocent passage through the parts of the passage forming the territorial sea and are largely subject to freedom of navigation through those parts that form the exclusive economic zone. However, it seems likely that the Northwest Passage is a strait used for international navigation, in which case, the vessels passing through it are instead subject to the regime of transit passage. This would negatively affect the possibility for Canada to issue national legislation to regulate pollution from foreign vessels. However, as long as the Northwest Passage is covered by ice for most of the year, article 234 UNCLOS allows Canada far more leeway in regard to issuing anti-pollution legislation, both in the territorial sea and the exclusive economic zone, regardless of whether the Northwest Passage is found to be a strait used for international navigation. The passage regime applicable to foreign commercial vessels under article 234 could be characterised as a sui generis passage.

Abstract The aim of this study is to identify the positive contributions women of colour (WOC) bring to higher education as they experience the process of becoming doctoral recipients. Their experiences are presented as a new epistemology—a theory of knowledge—as part of the larger area of cultural capital theory. The experiences of WOC in Canadian doctoral programs are conceptualized as ‘cultural wealth’ and new knowledge because evidence reveals that the intrinsic value of their contributions has evolved from unique cultural and historical resources. The discursive theoretical frameworks of Womanist theory, critical race theory (CRT) and cultural capital theory are utilized to guide the analysis of the findings. This study establishes the experiences of the participants as valuable and distinctive knowledge by emphasizing the intersectionality of race, class, gender, culture, and spirituality. The research suggests that the experiences of women of colour are informed by an inner wisdom woven from the mosaic, or uniquely diverse paths, which these women have taken toward earning their doctorate degree. The existing interpretation of cultural capital theory - originally established by Bourdieu and Passeron (1977) - is considered the only social marker of wealth in socio-economical and educational research. Although previous studies have challenged this dominant perspective, this current study presents a unique interpretation of cultural capital theory by expanding the notion of cultural wealth from a Canadian perspective. This study highlights the importance of the racial/cultural context that is highly visible in Canadian culture but seldom addressed in higher education research. In addition, the aim of my study is to establish the wealth of “Mosaic Paths” found among the cultural identity of WOC, as a new epistemology in Canadian higher education. Specifically, the journey toward achieving a doctoral degree is often over-generalized in higher education. This study will reveal the realistic paths that WOC must traverse in order to realize their goals. Finally, the findings from the data reveal six major sources of cultural wealth: 1) Mother’s Influence, 2) Age Capital, 3) Mentorship, 4) Survival Strategies, 5) Negotiating Academic Culture or Know-how, and 6) Spirituality.

Abstract The aim of this study is to identify the positive contributions women of colour (WOC) bring to higher education as they experience the process of becoming doctoral recipients. Their experiences are presented as a new epistemology—a theory of knowledge—as part of the larger area of cultural capital theory. The experiences of WOC in Canadian doctoral programs are conceptualized as ‘cultural wealth’ and new knowledge because evidence reveals that the intrinsic value of their contributions has evolved from unique cultural and historical resources. The discursive theoretical frameworks of Womanist theory, critical race theory (CRT) and cultural capital theory are utilized to guide the analysis of the findings. This study establishes the experiences of the participants as valuable and distinctive knowledge by emphasizing the intersectionality of race, class, gender, culture, and spirituality. The research suggests that the experiences of women of colour are informed by an inner wisdom woven from the mosaic, or uniquely diverse paths, which these women have taken toward earning their doctorate degree. The existing interpretation of cultural capital theory - originally established by Bourdieu and Passeron (1977) - is considered the only social marker of wealth in socio-economical and educational research. Although previous studies have challenged this dominant perspective, this current study presents a unique interpretation of cultural capital theory by expanding the notion of cultural wealth from a Canadian perspective. This study highlights the importance of the racial/cultural context that is highly visible in Canadian culture but seldom addressed in higher education research. In addition, the aim of my study is to establish the wealth of “Mosaic Paths” found among the cultural identity of WOC, as a new epistemology in Canadian higher education. Specifically, the journey toward achieving a doctoral degree is often over-generalized in higher education. This study will reveal the realistic paths that WOC must traverse in order to realize their goals. Finally, the findings from the data reveal six major sources of cultural wealth: 1) Mother’s Influence, 2) Age Capital, 3) Mentorship, 4) Survival Strategies, 5) Negotiating Academic Culture or Know-how, and 6) Spirituality.