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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.
271

Relief representation : time to get 'back to basics'?

McCrorie, Ian January 1995 (has links)
This thesis examines the evolution of the now dominant contour method of relief representation, associated interpretation problems and attempted solutions. A hybrid method of relief representation is then suggested combining a standard topographic map, to provide quantitative data, and computer generated three-dimensional visualisations, to give topographic structure. The hypothesis that this system will result in improved performance at relief interpretation tasks, particularly for inexperienced map users, was then tested. A second aspect of the hypothesis centred on the colouring of the 3-D views. Thus the experiment was expanded to assess if the more natural impression provided by layer colouring resulted in improved performance. The principle evaluation involved 2 Objective Tests of user performance. Subjective assessment of 3-D visualisation production and quality and Opinion Samples were also used in the overall evaluation. This thesis concludes that the three-dimensional information tested here has not produced the expected improvement. Reasons suggested for this include lack of training with 2 and 3 dimensional data, unfamiliarity with computer generated three-dimensional views and inability of inexperienced map users to manipulate complex three-dimensional imagery. Suggested improvements to the theory include increased training and use of more specifically targeted views, for example, to illustrate a walking route using a series of views along its course.
272

The effects of content complexity and transitions on programs of action in a high school classroom.

Scarborough, Harriet Sheila Arzu, Scarborough, Harriet Sheila Arzu January 1990 (has links)
The purpose of this study was to examine the program of action of activities under the conditions of transition and content complexity. The path of the program of action was explored through a number of classroom activities in the areas of writing, literature, vocabulary, and grammar. In particular the configuration and the management of the program of action were examined to determine what was done by classroom inhabitants to guide and protect the program of action of activities. The setting of the study was a freshman honors English class in a southwest urban high school. The teacher was identified as an able manager, a factor that was expected to limit the competing vectors that might be triggered by discipline problems. Observations of the class were done over ten weeks or a quarter of the school year. The third period class was observed daily, and a total of forty activities were gathered and analyzed. Data analysis was done over a period of seven months. A quantitative summary of the activities showing activity types and time devoted to each activity type was compiled. The activity summaries were scanned to note emerging patterns. Programs of action of each activity type were mapped to illustrate the configuration and maintenance of the program of action and the emergence and handling of competing vectors. The final phase of the analysis was the comparison of programs of action across two levels of content complexity. Findings showed that the life of the program of action in classrooms varied according to activity type. The teacher emerged as the controller of action as illustrated by his choice of content presentation modes and activities. The comparison of programs of action of activities across content complexity showed that students participated more in the maintenance and sustenance of the program of action in activities in which the content was less complex than they did in activities with more complex content. Furthermore, when the content was more complex, the teacher's control of the maintenance of the program of action was more apparent. The length of transition was found to impact negatively the subsequent program of action. On the other hand, lengthy opening activities emerged as contributors to the maintenance of programs of action.
273

O processo de aprendizagem da cartografia escolar por meio da situação didática / The learning process of school cartography through a teaching situation

Aguiar, Waldiney Gomes de 10 May 2013 (has links)
A tese que ora apresentamos foi desenvolvida com professores da Educação Básica, Ciclo I do Ensino Fundamental, 5º ano, em escolas vinculadas à Secretaria Municipal de Educação da cidade de Francisco Beltrão (PR). Buscando contribuir com o ensino de Geografia para alunos das séries iniciais, desenvolvemos uma pesquisa com os docentes acerca de suas práticas em sala de aula junto aos alunos. Nosso objetivo principal foi observar como se dava tal ensino no que respeita ao trabalho com mapas. Nesse sentido, recorremos à proposta elaborada por Simielli (1994), que trata da alfabetização cartográfica. Segundo ela, para que a criança possa desmistificar o desenho, é preciso desenvolver alguns conceitos, tais como visão oblíqua, visão vertical, imagem tridimensional e bidimensional, além de compreender o alfabeto cartográfico (ponto, linha e área). A partir daí, a criança desenvolve a noção de legenda, proporção, lateralidade, referência e orientação, passando a conceber os mapas como meio de comunicação. Para ensinar todo esse processo, valemo-nos da teoria da situação didática sugerida por Brousseau (2008), que consiste em um modelo que descreve as atividades do professor e do aluno a partir de uma situação a ser resolvida. Trata-se de um instrumento de comunicação entre professor, meio e aluno, em busca de respostas a partir de 9 desafios que levem à construção de conhecimentos. Em nosso caso, conhecimentos geográficos e cartográficos, pois esta pesquisa passa pela questão de aprender o mapa e aprender Geografia por meio do mapa. / The current thesis has been developed with teachers from Elementary School, 1stcycle of Elementary School, 5º year in public schools of the city of Francisco Beltrao (PR). Trying to contribute with the Geography teaching of Elementary students, it has been developed a survey among the teachers about their teaching methodology toward the students. The main objective has been to observe how they worked when teaching about maps. With this aim, it has been worked on the Simiellisproposal(1994), which is about cartographic literacy. According to her, for a child to demystify the draw, it is necessary to develop some concepts, such as an skewed view, vertical view, three-dimensional and bi-dimensional image, besides to understand the cartographic alphabet (dot, line and area). From this point, the child develops the notion of subtitles, proportion, laterality, reference and orientation, conceiving the maps as a means of communication. To teach all this process, it has been used teaching situation theory suggested by Brousseau(2008), which consists in a model that describes the teacher and student activities from a situation to be solved. It is about a communication instrument between the teacher, environment and student, seeking answers from challenges that lead to the 11 construction of knowledge. In our case, geographical knowledge, because this survey is about learning maps and learning Geography through maps.
274

Safe Configurable Maps for Off-Road Sites : Proposed methods for safe and efficient map updates for autonomous trucks

Christoffersson, Joakim January 2019 (has links)
Autonomous vehicle technology is advancing at a very high pace and self-driving trucks on control-tower operated work sites is already a reality. These autonomous trucks need a highly accurate map of the surroundings for operation and navigation, and it is of great importance to be able to update that map with the ever-changing off-road work site. The autonomous fleet examined have to stop for every update of the site map, which induces unnecessary downtime when updating the site map frequently. The purpose of this work is to contribute to the development of safe configurable maps for autonomous vehicles on off-road sites by identifying and analyzing different map updating methods, proposing the best one, and suggesting how to implement it for this project's case. The result was five different map updating methods, which were evaluated with respect to efficiency and safety. Efficiency was evaluated by comparing total fleet downtime of the proposed solutions with the existing situation. Safety was evaluated by doing a fault tree analysis (FTA) for each proposed solution and comparing the relative size of the fault trees. Proposed Solution III using map tiles was chosen as the most appropriate method to implement for this project's case because it is both efficient and relatively simple. It divides the site map with a grid into smaller rectangular maps and only needs to stop vehicles which are inside the updated tile. The rest of the fleet is able to replace that tile parallel to operation and, therefore, total fleet downtime is significantly reduced. By reaching the stated goal, this work is in line with its original purpose and has contributed to the development of safe configurable maps for autonomous vehicles on off-road sites.
275

Classificação de aplicações estáveis através do uso de grafos / Classification of stable maps through the use of graphs

Dias, Markus Diego Sampaio da Silva 30 March 2012 (has links)
Neste projeto inicia-se o estudo de classificação de aplicações estáveis. Para isto usamos grafos que irão corresponder ao conjunto singular destas aplicações. Em um primeiro momento estudamos o caso de aplicações estáveis de superfícies no plano e depois estudamos aplicações estáveis de 3-variedades em \'R POT. 3\' / In this project we began the study of classification of stable maps. For this we use graphs that correspond to the singular set of these applications. At first we study the case of stable maps of surfaces in the plane and then we study stable maps of a 3-manifold in \'R POT. 3\'
276

Monotonicity formulae in geometric variational problems.

January 2002 (has links)
Ip Tsz Ho. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 86-89). / Chapter 0 --- Introduction --- p.5 / Chapter 1 --- Preliminary --- p.11 / Chapter 1.1 --- Background in analysis --- p.11 / Chapter 1.1.1 --- Holder Continuity --- p.11 / Chapter 1.1.2 --- Hausdorff Measure --- p.12 / Chapter 1.1.3 --- Weak Derivatives --- p.13 / Chapter 1.2 --- Basic Facts of Harmonic Functions --- p.14 / Chapter 1.2.1 --- Harmonic Approximation --- p.14 / Chapter 1.2.2 --- Elliptic Regularity --- p.15 / Chapter 1.3 --- Background in geometry --- p.16 / Chapter 1.3.1 --- Notations and Symbols --- p.16 / Chapter 1.3.2 --- Nearest Point Projection --- p.16 / Chapter 2 --- Monotonicity formula and Regularity of Harmonic maps --- p.17 / Chapter 2.1 --- Energy Minimizing Maps --- p.17 / Chapter 2.2 --- Variational Equations --- p.18 / Chapter 2.3 --- Monotonicity Formula --- p.21 / Chapter 2.4 --- A Technical Lemma --- p.22 / Chapter 2.5 --- Luckhau's Lemma --- p.28 / Chapter 2.6 --- Reverse Poincare Inequality --- p.40 / Chapter 2.7 --- ε-Regularity of Energy Minimizing Maps --- p.45 / Chapter 3 --- Monotonicity Formulae and Vanishing Theorems --- p.52 / Chapter 3.1 --- Stress energy tensor and basic formulae for harmonic p´ؤforms --- p.52 / Chapter 3.2 --- Monotonicity formula --- p.59 / Chapter 3.2.1 --- Monotonicity Formula for Harmonic Maps --- p.64 / Chapter 3.2.2 --- Bochner-Weitzenbock Formula --- p.65 / Chapter 3.3 --- Conservation Law and Vanishing Theorem --- p.68 / Chapter 4 --- On conformally compact Einstein Manifolds --- p.71 / Chapter 4.1 --- Energy Decay of Harmonic Maps with Finite Total Energy --- p.73 / Chapter 4.2 --- Vanishing Theorem of Harmonic Maps --- p.81 / Bibliography --- p.86
277

A programmed method for the computation of brine and solid phase reserves of evaporite lake deposits

Winters, Harry Joseph, 1939-, Winters, Harry Joseph, 1939- January 1967 (has links)
No description available.
278

Route Descriptions Using Maps, Photomaps, and Imagery: An Experimental Analysis

Kelley, Maureen 11 July 2013 (has links)
Previous route description experiments conducted by psychologists show there are differences between males and females in the use of landmarks when describing routes. Previous research has shown that females used landmarks and egocentric forms of turn descriptors more often than males for route descriptions. This method is known as route knowledge in the spatial knowledge literature. Males, conversely, were seen to use fewer landmarks and more cardinal direction descriptions and standard distances when describing routes. Spatial knowledge literature terms this method survey knowledge. The current experiment tested the hypothesis that sex is not the determinant of landmark usage for route descriptions but different cartographic methods depicting the same locale determine whether landmarks are described. Two quasi-experiments were conducted using different map types. Results of the experiments show that map type, not sex, influences landmark usage for route descriptions. / 10000-01-01
279

Wayfinding modelling using cognizing agent for evacuation simulation of multi-level buildings.

January 2014 (has links)
在建築物應急疏散過程中,人員個體的路徑選擇將影響人群整體的疏散情況。空間認知研究表明,人們通過認知獲取空間知識,並在認知地圖的指引下完成尋徑任務,尋徑過程因人而異。應急疏散時,建築物內部空間時有變化,心理壓力和人群活動等都將影響人員的路徑選擇。然而,現有疏散模型通常採用路徑搜索演算法來類比人員的逃生路徑。該方法多以最優路徑為目標,難以類比真實的尋徑過程,不能反映個體間的尋徑差異。因此,準確模擬人員個體的尋徑行為是建築物疏散模擬的研究重點。通過類比不同人群的疏散情況,採取針對性的疏散引導,可以有效緩解擁堵,提高疏散效率。 / 鑒於以上背景,本文以模擬多層建築中不同人群的疏散情況為目標,基於尋徑行為理論,考慮人群活動和室內空間變化的影響,分析建築物疏散時各類人員的尋徑行為,從而構建基於認知智慧體的疏散模型,類比多層建築的人員疏散。研究從以下方面展開: / (1)研究尋徑行為理論,分析建築物疏散時人員尋徑的知識需求和尋徑策略,考慮人群活動對個體尋徑的影響,構建建築物應急疏散時人員尋徑的過程模型。 / (2)研究建築物內部空間的表達方法,提出針對人群疏散類比的建築物空間表達模型。該模型在宏觀上採用基於語義的方法構建了的考慮消防設施的動態空間拓撲結構,在微觀上採用網格模型表達建築物內部幾何空間。 / (3)基於尋徑過程模型和建築物空間表達模型,構建基於認知智慧體的建築物疏散模型。智慧體行為模型以尋徑過程模型為理論基礎,包括知識表達,尋徑模型,環境認知模型和运動模型。 / (4)以某大學教學樓為例,驗證模型的可行性。考慮日常教學和籌辦會議等典型情況下的人群構成,模擬各個人群在不同火災場景下的疏散過程。通過對比出口使用率,分析不同人群的疏散差異。 / 研究結果表明,本文構建的建築應急物疏散模型能夠類比多層建築中各類人員的尋徑行為,反應不同人群的疏散差異,模擬結果更為合理,可以有效輔助人群疏散管理。 / In building evacuation, escape route choice of individual evacuees will potentially affect the overall evacuation performance. Studies in spatial cognition suggest that people find their ways based on spatial knowledge developed from environmental perception. Therefore, people with different level of spatial knowledge may vary tremendously in wayfinding performance. In the emergency situation, the building’s internal structure may change as some built-in facilities are activated. In the meantime, people’s psychic stress and crowd dynamics will significantly affect evacuees’ route selection. However, in most evacuation models, evacuees are simulated as particles that automatically follow the optimal escape route, and consequently without taking into account individual differences in wayfinding. Therefore, modelling individualized wayfinding is a critical issue in building evacuation simulation. It is expected that evacuation simulations regarding different types of evacuees would benefit the evacuation management targeted at a particular group of people. / Given the aforementioned background, the goal of this research is to model evacuees’ route choice in a plausible way by taking into account the cognitive process of human wayfinding and hereby perform evacuation simulations of different groups of evacuees in a multi-level building. In order to reach this goal, the following studies have been conducted: / (1) Based on literature studies on human wayfinding, a process model of wayfinding has been established. With regard to the emergency situation of building evacuation, typical wayfinding tasks, knowledge requirement, individual wayfinding strategies and influence of surrounding crowds are elaborated and incorporated into the process model. / (2) A novel approach to represent the dynamic spatial environments is developed to facilitate the evacuation simulation of multi-level buildings. At the macro level, a semantics-based model is established to represent the topological structure of building interiors which can be timely updated according to the status of fire safety facilities during emergency evacuation. At the micro level, a grid graph-based model is adopted to represent the geometry of building layout in order to facilitate the simulation of two-dimensional human movement. / (3) On the basis of the process model of wayfinding and the representation of dynamic spatial environment of building interiors, a computational model is developed using cognizing agent for building evacuation simulation. The architecture of the cognizing agent consists of knowledge representation, wayfinding model, environmental perception model and local movement model. / (4) The proposed model is verified and applied for the evacuation simulation of a university building. A series of evacuation simulations have been conducted in different fire scenarios with respect to the particular groups of evacuees in school days and conference days. Based on statistical analyses of exit utilization, evacuation performance of different groups of evacuees has been discussed and compared. / It has been proven that the proposed evacuation model, which incorporates the cognitive perspectives of human wayfinding, is capable of simulating a variety of route choice of different types of evacuees during the evacuation of a multi-level building. The model can be used to simulate the evacuation of different groups of evacuees, and thus provide more realistic basis for building evacuation management. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Tan, Lu. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 137-148). / Abstracts also in Chinese.
280

Periodic Points and Surfaces Given by Trace Maps

Johnston, Kevin Gregory 01 June 2016 (has links)
In this thesis, we consider the properties of diffeomorphisms of R3 called trace maps. We begin by introducing the definition of the trace map. The group B3 acts by trace maps on R3. The first two chapters deal with the action of a specific element of B3,called αn. In particular, we study the fixed points of αn lying on a topological subspace contained in R3, called T . We investigate the duality of the fixed points of the action ofαn, which will be defined later in the thesis.Chapter 3 involves the study of the fixed points of an element called γnm, and it generalizes the results of chapter 2. Chapter 4 involves a study of the period two points of γnm. Chapters 5-8 deal with surfaces and curves induced by trace maps, in a manner described in chapter 5. Trace maps define surfaces, and we study the intersection of those surfaces. In particular, we classify each such possible intersection.

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