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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.
181

The potentials for integrated underground space development in urban planning: a case study of Shanghai city

Li, Yan, 李硯 January 2009 (has links)
published_or_final_version / Urban Planning and Design / Master / Master of Science in Urban Planning
182

Application of reliability methods to the design of underground structures

Langford, John Connor 18 September 2013 (has links)
Uncertainty in rockmass and in situ stress parameters poses a critical design challenge in geotechnical engineering. This uncertainty stems from natural variability (aleatory) due to the complex history of formation and continual reworking of geological materials as well as knowledge-based uncertainty (epistemic) due to a lack of site specific information and the introduction of errors during the testing and design phases. While such uncertainty can be dealt with subjectively through the use of conservative design parameters, this leads to a lack of understanding of the variable ground response and the selection of an over-conservative design that can have a negative impact on both the project cost and schedule. Reliability methods offer an alternative approach that focuses on quantifying the uncertainty in ground conditions and utilizing it directly in the design process. By doing so, a probability of failure can be calculated with respect to a prescribed limit state, providing a measure of design performance. When multiple design options are considered, reliability methods can be paired with a quantitative risk analysis to determine the optimum design on the basis of safety and minimum cost rather than subjective conservatism. Despite the inherent benefits of such an approach, the adoption of reliability methods has been slow in geotechnical engineering due to a number of technical and conceptual challenges. The research conducted pertaining to this thesis aims to address these issues and remove the perceived “cloak of mystery” that surrounds the use of reliability methods. The scientific and engineering research in this thesis was divided into four sections: (1) the assessment of uncertainty in geotechnical input parameters, (2) a review of reliability methods in the context of geotechnical problems, (3) the development of a reliability-based, quantitative risk approach for underground support design and (4) the application of such a method to existing case studies. The completion of these areas is critical to the design of underground structures and may bring about a shift in design philosophy in the geotechnical industry. / Thesis (Ph.D, Geological Sciences & Geological Engineering) -- Queen's University, 2013-09-18 10:35:26.265
183

A mulher do subsolo em Niétotchka Niezvânova de F. M. Dostoiévski / The Woman from the Underground in Netochka Niezvanova by F. M. Dostoyevsky

Freitas, Marcia Maria Oliveira 30 January 2019 (has links)
Em 1849, Dostoiévski publica Niétotchka Niezvânova. No centro da narrativa temos uma mulher cujos fatos de sua vida (na infância) são trazidos à tona pelo seu próprio ponto de vista. Suas memórias, dadas as ambiguidades presentes, vão ao encontro de Memórias do Subsolo, publicada em 1864. Memórias, apesar de ser uma obra posterior de Dostoiévski em relação à Niétotchka Niezvânova, faz-nos pensar em muitos procedimentos literários e temas desenvolvidos que já fermentavam antes, de algum modo e com certas particularidades, nesta obra que será analisada aqui. Haverá um esforço em demonstrar como Niétotchka (uma mulher) fala do seu subsolo e como aquilo que é narrado em primeira pessoa, da maneira como é exposto a nós leitores, diz-nos muito sobre o verdadeiro caráter desta personagem feminina. O que nos leva, inevitavelmente, a uma questão fundamental na elaboração da personagem: a marginalização do ser humano, em seus diversos aspectos, que pretendemos discorrer ao longo da pesquisa apresentada aqui. / In 1849, Dostoevsky publishes Netochka Nezvanova, which has the plot focused ona woman that has thefacts of her life (in childhood) brought outthrough her own point of view. Her memories, given the held ambiguities, go against Notes from Underground, which was published in 1864. Although it came out later than Netochka Nezvanova, Notes makes us recall many literary methods and handled themes which, in some extent, were latent in the book analysed here. It will be sought to demonstrate how Netochka (a woman) speaks out from her underground and howher first-person narrative, as it is exposed to us readers, says a lot about the true nature of this female character. It leads us, inevitably, to a fundamental pointin the creation of such a character: the many facets of human marginalisation, which we intend to discourse along this research.
184

Prediction of the initiation and orientation of the extension fractures ahead of and around faces and walls of mechanically driven excavations and their effect of stability

Mokgohloa, Matthews Chuene January 2017 (has links)
Thesis is submitted in partial fulfilment of the requirements for the degree of Master of Science in Engineering to the Faculty of Engineering and the Built Environment, School of Mining Engineering, University of the Witwatersrand, Johannesburg, 2017 / Boring of shafts and tunnels in hard rock mines is more prevalent in recent years in South Africa. This normally takes place under substantial stress conditions, where fracturing of rock occurs around the boundaries and ahead of advancing faces of excavations. Fracturing can have a significant impact on boring activities, in some instances causing sidewall spalling which can be extensive, with machine grippers unable to reach the sidewalls. In brittle rock, these fractures are commonly extensional in nature. This research has been undertaken to predict the initiation of extension fractures and their orientations ahead of machine driven tunnels. Furthermore, it will help to assess the stability of the excavations, by evaluating the potential for slab/plate failures. This was based on the typical in situ stress fields for underground deep level mines. The numerical analyses involved the generation of different plots:  Principal stress contour plots, depicting stress distributions around and ahead of tunnel excavation, using cutting planes;  Isosurfaces, showing zones of extension or potential extents of fracturing, applying the extension strain criterion; and  Trajectory ribbons, to demonstrate the orientations of fractures. Based on the results of the stress analyses, potential slab or plate formation was determined. It was noted that the fracture zone is a function of a tunnel size. For instance, a four-metre diameter tunnel is less likely to give boring problems than an eight-metre diameter tunnel. The failure of the tunnels was predicted by employing slab analysis methods. An eight-metre diameter tunnel had slenderness ratio as low as 22.3 as compared with a four-metre diameter tunnel with a slenderness ratio of 27. Looking at buckling stress versus slenderness ratio, this translates to buckling stress values of above 100 MPa for an eight-metre tunnel and to values just below 50 MPa for a four-metre tunnel. The outcome of the research gives a clear indication that boring activities could be undertaken under severe conditions. This could be detrimental to the cutter head, since large slabs and blocks could be encountered during boring. The results of this research can be beneficial in the evaluation of boring conditions prior to and during boring activities. / MT2018
185

Noise and whole-body vibration in underground locomotive operators

Southon, Sharon 16 March 2011 (has links)
MPH, Occupational Hygiene, Faculty of Health Sciences, University of the Witwatersrand / Introduction Locomotive operators in the mining industry are exposed to high levels of noise and vibration. There is currently limited information indicating whole-body vibration exposure levels conducted over an 8-hour time weighted average (TWA) exposure period; most of the available data are based on instantaneous measurements. The 10-Ton New Era locomotive was specifically designed with the focus on areas such as ergonomics, safety, future automation, productivity and flexibility of use. The locomotive has a single cab and can be driven and controlled with maximum visibility in the direction of travel. Most mining houses are converting from the use of the 10 Ton Goodman battery operated locomotive to the 10Ton New Era locomotive, hence the focus of noise and vibration measurements on the latter. Objectives This research report documents a project to measure noise and whole-body vibration exposure levels of locomotive operators working in an underground platinum mine. The objectives of the study are: • to describe the eight hour time weighted average occupational noise exposure levels of locomotive operators operating the 10-Ton New Era locomotive in an underground platinum mine over 2008 and 2009; • to describe personal whole-body vibration exposure levels of locomotive operators operating the 10-Ton New Era locomotive in an underground platinum mine over 2008 and 2009; and 5 • to determine whether personal noise and whole-body vibration exposure levels of locomotive operators operating the 10-Ton New Era locomotive in an underground platinum mine over 2008 and 2009 comply with national and international standards. Methods Personal noise and whole-body vibration exposure measurements were obtained from 21 underground locomotive operators. Measurements were conducted in accordance with the procedures described in the SANS 10083 standard for personal noise dosimetry and the ISO 2631-1 standard for whole-body vibration. Determination of likely health risks for the operators were based on a comparison of the measured time-weighted noise exposure levels with the South African OEL and the ACGIH threshold limit value; whole-body vibration levels were compared with the HGCZ limits presented in Annex B of the ISO 2631-1 standard and the EU directive daily exposure limits. Results The measured noise and whole-body vibration levels taken over an 8-hour TWA exposure period were higher when compared to national and international standards. The mean LTWA levels for noise was 66.5 dB(A) with 12.5% of the measurements exceeding the South African OEL of 85dB(A). 45% of the wholebody vibration measurements fell within the HGCZ indicating that whole-body vibration exposure on locomotive operators presents a moderate probability for an adverse health outcome. Discussion and Conclusion Locomotive operators are exposed to potentially harmful levels of noise and whole-body vibration. The Mine Health and Safety Act requires an employer to assess the health and safety risks that hazards pose to their employees, and to take reasonably practicable steps towards eliminating or controlling those risks. Like any other risks at a workplace, noise and whole-body vibration needs to be 6 identified and controlled, and the approach to be taken is one of a risk management
186

Determinação de Selênio em água subterânea utilizando a espectrometria de absorção atômica com atomização eletrotérmica em forno de grafita (GFAAS) e geração de hidretos (HGAAS) / Determination of selenium in underground water using atomic absorption spectrometry with graphite furnace (GFAAS) and hydride generation (HGAAS)

Gomes Júnior, Alcides 16 December 2008 (has links)
Relatório realizado pela CETESB em 2006 mostrou que 80% dos 645 municípios são total ou parcialmente abastecidos por água subterrânea e que em 13 bacias hidrográficas do Estado de São Paulo a água subterrânea é a fonte prioritária de abastecimento. O uso da água subterrânea em diversos setores reforça a sua importância e gera preocupações quanto a sua proteção e qualidade. A região noroeste do Estado de São Paulo, abastecida principalmente por captação de água subterrânea do aqüífero Guarani por meio de poços tubulares, apresenta ocorrência de Selênio. Assim, no presente trabalho procurou-se avaliar a contribuição de selênio em águas subterrâneas. Foram coletadas amostras de água subterrânea de quatro poços tubulares profundos captadas do aqüífero Guarani na região noroeste do Estado de São Paulo e foram realizadas medidas do elemento selênio, utilizando a espectrometria de absorção atômica com atomização eletrotérmica (GFAAS) e geração de hidretos (HGAAS). Além do selênio também foram analisados outros metais (B, Al, V, Cr, Mn, Ni, Cu, Zn, Mo, Sn, Li, Be, Mg, P, Ca, Fe, Ba, Co, Na, Si, K, Ag, Cd, Pb, Sb, Hg e As) por ICP OES em todas as amostras. A caracterização do selênio foi realizada com uma periodicidade de amostragem trimestral, no período de Março de 2006 a Março de 2007, totalizando cinco campanhas. O metal analisado neste estudo foi selecionado atendendo-se as exigências da legislação que avalia a qualidade da água para abastecimento publico, estabelecendo limites máximos permissíveis para concentração de metais: Portaria 518/2004 MS (VPM para Se: 0,010 mg/L), referente à potabilidade. As análises realizadas mostraram que as concentrações de Se estão acima do limite máximo permissível e que as técnicas atomização eletrotérmica (GFAAS) e geração de hidretos (HGAAS) demonstraram equivalência nos resultados. As análises demonstraram que a presença de Se parece estar associada a fatores mineralógicos (formação geológica da região) e as metodologias apresentaram-se eficientes com respostas similares diferenciando-se em fatores operacionais e de custo. / Report carried out for CETESB in 2006 showed 80% of the 645 cities are totally or partially supplied by underground water, and for 13 river basins of São Paulo State the underground water is the priority source for potable water supply. The use of underground water in different sectors reinforces its importance and highlight the concern about their protection and quality. The northwest region of São Paulo state is mainly supplied by underground water of the Guarani aquifer extracted by tubular wells, which presents some occurrence of Selenium. In the present study it was looked and evaluated, through the comparison of high sensitivity and selectivity methods as the atomic absorption spectrometry using electrothermal atomizaton (GFAAS) and the hydride generation (HGAAS). Underground water samples of four deep tubular wells of Guarani aquifer in the northwest of São Paulo state were collected to measure the selenium element. In addition to selenium other metals were analyzed (B, Al, V, Cr, Mn, Ni, Cu, Zn, Mo, Sn, Li, Be, Mg, P, Ca, Fe, Ba, Co, Na, Si, K, Ag, Cd, Pb, Sb, Hg and As). The characterization of selenium was carried out with quarterly sampling regularity, in the period of March of 2006 to March of 2007, totalizing five campaigns. The metal analyzed in this study was selected according to the requirements of the legislation for potable water quality evaluation, establishing permissible maximum limits for metal concentration. The results had shown the concentrations of Se are above of the maximum permissible limits and the techniques electrothermal atomization (GFAAS) and hydride generation (HGAAS) demonstrated equivalence in their results. The results demonstrated also the presence of Se can be associated with mineralogical factors (as geologic formation of the region) and the applied methodologies were efficient with similar answers for different operational factors and expenses.
187

An urban trans-station: Sai Ying Pun underground network & MTR station development.

January 1998 (has links)
Cheng Ho Kei Matthew. / "Architecture Department, Chinese University of Hong Kong, Master of Architecture Programme 1997-98, design report." / Chapter PART I --- INTRODUCTION --- p.P.5 / Chapter - --- personal design objective --- p.P.6 / Chapter - --- the subject --- p.P.7 / Chapter - --- the clients & users --- p.P.8 / Chapter - --- the site & context --- p.P.8 / Chapter PART II --- PROJECT ANALYSIS --- p.P.10 / Chapter - --- subject analysis --- p.P.11 / Chapter - --- client / user. analysis --- p.P.18 / Chapter - --- site / context analysis --- p.P.25 / Chapter PART III --- PROJECT FORMATION --- p.P.32 / Chapter - --- mission --- p.P.33 / Chapter - --- design strategy --- p.P.34 / Chapter - --- design development --- p.P.36 / Chapter PART IV --- FINAL PROJECT --- p.P.45 / Chapter - --- final design --- p.P.46 / Chapter - --- conclusion --- p.P.58 / Chapter PART V --- FINAL PRESENTATION --- p.P.59 / Chapter - --- final presentation panels --- p.P.60 / APPENDIX --- p.P.61 / Chapter '-i. --- "/project planning, finance & fee estimations (12-1997)" --- p.P.62 / Chapter -ii. --- /programming report (12-1997) --- p.P.63
188

Beyond massive attack: MTR as a catalyst for revitalization by retaining local qualities.

January 2007 (has links)
Chu Pak Lin, Parry. / "Architecture Department, Chinese University of Hong Kong, Master of Architecture Programme 2006-2007, design report." / Chapter 1.0 --- Thesis Statement / Chapter 2.0 --- Background Information / Chapter 3.0 --- Architectural Issues of MTR Station & Underground Space / Chapter 4.0 --- Research & Approaches / Chapter 5.0 --- Site Studies / Chapter 6.0 --- The Design
189

Building Information Modeling (BIM): Site-Building Interoperability Methods

wang, menglin 07 September 2011 (has links)
"Nowadays, many companies in the Architecture/Engineering/Construction (AEC) industry are using Building Information Modeling (BIM) in achieving a faster, sustainable and more economic project. Among the new developed concepts and BIM applications, two of the concepts most frequently used with the support of BIM technology in the planning, organization and scheduling of projects are 4D and 5D in which a 3D model is tied to its time execution (4D) at any point in time and its corresponding cost (5D). However, most of these applications concentrate on modeling the building but it does not include a corresponding modeling of the site in which the building is located. To date, there are few studies and systematic implementation of the site and the building integrated into one BIM model. This site-building integrated model can also be conceptualized as ¡°6D BIM¡± model. The benefit of integrating the site and building together into one model is that the building is no longer treated in isolation of its surround site but incorporates extremely helpful short-term and long-term information for the owner, designer, and builder regarding site topography, landscaping, access roads, ground conditions and the location of site utilities. Major existing research and technology issues that are preventing this site-building integration deal with functionality and interoperability of the BIM software, different orientation and coordination of building model and site model. The objectives of this thesis are to explore current organizational and technological issues preventing this integration, to investigate a feasible method to create a site-linked BIM model, and to discuss the benefits and limitations of bringing BIM concept to the site conditions. The research has been conducted by an extensive review on the literature related to the topic of interest published primarily by AEC. A review on current applications of Geographic Information Systems (GIS) has also been included because of the wider context provided by this technology to the specific topic of this research. Related BIM software developed by three different vendors ¡ªhas been discussed and compared to determine the level of feasibility and operational features of technological support necessary to implement the site-linked BIM model. A case study based on the design and construction of the WPI Recreational & Sports Center, currently under construction, was developed to explore and understand the details that are involved in creating a new site model and to link it with the existing 3D building model. What has been learned from the analysis of this case study is presented, discussed and analyzed in terms of benefits and limitations. Recommendations for future extensions from both the research aspect and the technology support aspect finally presented. These include the creation of 3D BIM Campus Map, which is one site model with several building models placed on it to facilitate future planning of new building and/or maintenance and operation of the current buildings and campus infrastructure.   "
190

Effect of concentrated loads on shallow buried polyvinyl chloride and polyethylene tubing.

McGrath, Timothy James January 1975 (has links)
Thesis. 1975. M.S.--Massachusetts Institute of Technology. Dept. of Civil Engineering. / Includes bibliographical references. / M.S.

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