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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.
211

The behaviour of very high strength (VHS) members and welded connections

Jiao, Hui, 1963- January 2003 (has links)
Abstract not available
212

Evaluation Of Best Environmental Management Practices Of An Integrated Iron And Steel Plant

Cakir, Nur 01 September 2012 (has links) (PDF)
European Union published IPPC Directive in 1996 aiming to create an integrated approach in order to manage and control industrial facilities better. IPPC provides the development of a new concept of &ldquo / Best Available Techniques (BAT)&rdquo / , the most effective, advanced and applicable methods, preventing emissions to the environment and providing efficient use of resources. Within this framework, numerous sectoral Best Available Techniques Reference Documents were published giving information on the sector and BAT alternatives for this sector. Iron and steel industry, which causes quite significant amount of resource depletion and waste production, is one of the industries within the scope of IPPC Directive. In the this study, environmental performance of an integrated iron and steel plant in Turkey is evaluated and compared with the EU&rsquo / s integrated iron and steel plants, in order to suggest applicable BAT alternatives for the studied plant. Totally 74 BAT alternatives were evaluated and among them 36 alternatives were determined to be applicable for this plant. Finally, two of these applicable BAT alternatives were selected and compared by use of cross-media effects and financial analysis. The results of this study indicated that dust emission and high energy consumption are the common problems in the facility. Moreover, sintering process was found to be the least compatible sub-process with EU&rsquo / s iron and steel plants. Additionally, it was determined that with respect to application of BAT alternatives, facility is quite compatible with EU&rsquo / s iron v and steel plants. Furthermore, cross media effect and financial analysis revealed that the selected BAT alternatives, &ldquo / Advanced Electrostatic Precipitator (ESP)&rdquo / and &ldquo / Bag Filter-combined or integrated reduction of solid and gaseous pollutants&rdquo / , have different cross media effects on the environment, however, the second alternative is a more cost-effective alternative than the first one. Since this study was undertaken in an integrated iron and steel plant that represents Turkish iron and steel industry with respect to its production process, production capacity and environmental performance / the results of this study can be used to aid decision makers to make environmental initiatives in iron and steel industry in Turkey.
213

Assessment Of Factory Campus Development In Turkey Through An Urban Design Perspective: The Case Of Iskenderun Iron And Steel Factory Campus

Kimyon, Deniz 01 February 2013 (has links) (PDF)
Thesis aims to elaborate the urbanism ideology developed in the early republican period of Turkey and its reflection on the development of factory campuses. In Turkey after the Ottoman Empire, new state with its own ideology has impact on shaping urban space, politics of urban forms development, urban morphology and urban metamorphosis. This thesis examines various factory campuses designed and built after the establishment of the Turkish Republic, and focuses on a later campus development / namely Iskenderun Iron and Steel Factory Campus. The study notes the dissolution of factory-housing togetherness, and points to the design values in the case study presented.
214

Landscapes of Technology Transfer : Swedish Ironmakers in India 1860–1864

af Geijerstam, Jan January 2004 (has links)
<p>In the early 1860s three Swedes, Nils Wilhelm Mitander,Julius Ramsay and Gustaf Wittenström, were engaged by theBritish to build and run charcoal-based ironworks in India.These works, the Burwai Iron Works of the British Government inthe case of Mitander and the privately owned Kumaon Iron Worksin the case of Ramsay and Wittenström, were both to bebased on the most modern European technology. The projects werepioneering in Indian ironmaking. The ambitions were high andstakes big, but after only a few years the projects were closedand the Swedes returned home.<i>Landscapes of Technology Transfer</i>presents a detailedstudy of the Kumaon and Burwai Iron Works, from their firstconception to their final closure. The investigation isbasically empirical and a fundamental question is: Why were theworks never brought into full and continuous production?</p><p>The ironworks projects should be considered as processes oftechnology transfer rather than fully fledged and completedtransfers. In spite of this lack of success, or maybe becauseof it, the history of the ironworks and the Swedes also forms afruitful case to put other questions of wide relevance. Itexposes workings and effects of colonialism and offers anexplanation of the late development of India's iron and steelindustry and analyses of the complex totality forming theprerequisites for a successful transfer of technology. The longtraditions of bloomery ironmaking in India and ismarginalisation is also discussed.</p><p><i>Landscapes of Technology Transfer</i>is a comprehensiveempirical study. From a local and individual perspective ittraces lines of connection across boundaries of time andgeography. The historical landscapes of technology transfer aredescribed in their cultural, social, economic and politicaldimensions and the thesis underlines the importance of a closeacquaintance with local settings and conditions, where historyis manifested in a physical presence. The remains of theironworks and theirlocal landscapes in present-day India areused as a central source for writing their histories. There isalso a strong emphasis on the use of photographs and drawingsas sources.</p><p>The outcome of the projects was the result of the interplaybetween the local and the global, between a diversity ofconcrete factors influencing the construction of the works andtheir running and their colonial character. The studyemphasises the importance of technological systems andnetworks, both on a micro and a macro level. On a local leveldemanding logistics, a sometimes adverse climate, theprocurement of charcoal and iron ore in sufficient quantitiesand the build up of knowledge of ironmaking posed serious butnot insurmountable difficulties. Most obstacles were overcomealready during the first few years of the 1860s, the period ofthe Swedes, but to put the works into full and continuousproduction would have needed perseverance and purposefulefforts to support and protect the iron production, at leastduring an initial period. In the end the position of India as acolonial dependency, subjected to the primacy of Britishinterests, set the limits of the projects.</p><p><b>Key words:</b>History of technology, industrial heritagestudies, industrial archaeology, technology transfer,diffusion, technological systems, landscapes of technology,iron and steel, charcoal iron, direct and indirect ironmaking,bloomeries, 19th century, industrial history,industrialisation, de-industrialisation, underdevelopment,colonialism, India, Sweden, Great Britain, global history,annales.</p>
215

Strengthening existing steel bridge girders by the use of post-installed shear connectors

Kwon, Gun Up, 1977- 28 September 2012 (has links)
A number of older bridges built before the 1970’s were constructed with floor systems consisting of a non-composite concrete slab over steel girders. Many of these bridges do not satisfy current load requirements and may require replacement or strengthening. A potentially economical means of strengthening these floor systems is to connect the existing concrete slab and steel girders to permit the development of composite action. This dissertation describes a research program investigating methods to develop composite action in existing non-composite floor systems by the use of postinstalled shear connectors. Three types of post-installed shear connection methods were investigated. These methods are referred to as the double-nut bolt, the high tension friction grip bolt, and the adhesive anchor. These post-installed shear connectors were tested under static and fatigue loading, and design equations for ultimate strength and fatigue strength were developed. These post-installed shear connectors showed significantly higher fatigue strength than conventional welded shear studs widely used for new construction. The superior fatigue strength of these post-installed shear connectors enables strengthening of existing bridge girders using partial composite design, thereby requiring significantly fewer shear connectors than possible with conventional welded shear studs. Five full-scale non-composite beams were constructed and four of these were retrofitted with post-installed shear connectors and tested under static load. The retrofitted composite beams were designed as partially composite with a 30-percent shear connection ratio. A non-composite beam was also tested as a baseline specimen. Test results of the full-scale composite beams showed that the strength and stiffness of existing non-composite bridge girders can be increased significantly. Further, excellent ductility of the strengthened partially composite girders was achieved by placing the postinstalled shear connectors near zero moment regions to reduce slip at the steel-concrete interface. Parametric studies using the finite element program ABAQUS were also conducted to investigate the effects of beam depth, span length, and shear connection ratio on the system behavior of strengthened partially composite beams. The studies showed that current simplified design approaches commonly used for partially composite beams in buildings provide good predictions of the strength and stiffness of partially composite bridge girders constructed using post-installed shear connectors. / text
216

A framework for electricity generation opportunities in the South African integrated iron and steel industry : the ArcelorMittal Newcastle case / Marais, B.

Marais, Brendan January 2011 (has links)
Electricity availability and the costs thereof in South Africa were traditionally considered an abundant and low cost commodity, but in recent years this situation has changed altogether. Industries are challenged by a strained national electricity grid and tariff increases more than four times the national inflation rate over the past two years, with further tariff increases expected in subsequent years; thus, exposing industries to significant business risks that may jeopardise the sustainability of industries. With the majority of the national electricity supply derived from coal, South Africa's push to reduce carbon emissions exerts even more pressure on industries as electricity usage is inextricably linked to its carbon footprint. In addition, South Africa's reliance on cogeneration from industries for its 2010 - 2030 electricity capacity plan further promotes industries to become more self–sufficient concerning electricity generation. In view of the above, there is a need in the South African integrated iron and steel industry for a framework that collectively addresses the governing factors pertaining to electricity generation in this industry, technical and economical quantification of available technologies and implementation of these technologies. This dissertation researches the current driving/governing and the remediating factors to become more self–sufficient in terms of electricity generation. A framework for electricity generation opportunities in the integrated iron and steel industry is developed from the literature study and the researcher's own experience. The framework embodies four building blocks into a single and all–encompassing framework, which provides the necessary governing factors that quantify the potential need to pursue electricity generation/cogeneration, the technical and economical implications and, inevitably, the implementation requirements and guidelines. Validating the framework against case studies pertaining to ArcelorMittal Newcastle realised a correlation of between 84.6% to 97.6% concerning the technical parameters. In addition, the validation process also indicated that the framework is aligned with current practices applied by ArcelorMittal South Africa. The framework will enable South African integrated iron and steel industries to expand and adapt their own procedures to be specific to their operational requirements. The implementation of the framework should be tailored to address the specific needs concerning cogeneration in industry. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2012.
217

A framework for electricity generation opportunities in the South African integrated iron and steel industry : the ArcelorMittal Newcastle case / Marais, B.

Marais, Brendan January 2011 (has links)
Electricity availability and the costs thereof in South Africa were traditionally considered an abundant and low cost commodity, but in recent years this situation has changed altogether. Industries are challenged by a strained national electricity grid and tariff increases more than four times the national inflation rate over the past two years, with further tariff increases expected in subsequent years; thus, exposing industries to significant business risks that may jeopardise the sustainability of industries. With the majority of the national electricity supply derived from coal, South Africa's push to reduce carbon emissions exerts even more pressure on industries as electricity usage is inextricably linked to its carbon footprint. In addition, South Africa's reliance on cogeneration from industries for its 2010 - 2030 electricity capacity plan further promotes industries to become more self–sufficient concerning electricity generation. In view of the above, there is a need in the South African integrated iron and steel industry for a framework that collectively addresses the governing factors pertaining to electricity generation in this industry, technical and economical quantification of available technologies and implementation of these technologies. This dissertation researches the current driving/governing and the remediating factors to become more self–sufficient in terms of electricity generation. A framework for electricity generation opportunities in the integrated iron and steel industry is developed from the literature study and the researcher's own experience. The framework embodies four building blocks into a single and all–encompassing framework, which provides the necessary governing factors that quantify the potential need to pursue electricity generation/cogeneration, the technical and economical implications and, inevitably, the implementation requirements and guidelines. Validating the framework against case studies pertaining to ArcelorMittal Newcastle realised a correlation of between 84.6% to 97.6% concerning the technical parameters. In addition, the validation process also indicated that the framework is aligned with current practices applied by ArcelorMittal South Africa. The framework will enable South African integrated iron and steel industries to expand and adapt their own procedures to be specific to their operational requirements. The implementation of the framework should be tailored to address the specific needs concerning cogeneration in industry. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2012.
218

Monitoramento estrutural baseado na técnica de ondas Lamb para detecção de falhas em estruturas metálicas parafusadas / Structural monitoring basead on Lamb wave technique for the detection of flaws in metallic structures

Silva Junior, Anorosval Pedro Leirias da 22 December 2017 (has links)
Este trabalho objetiva o estudo e a aplicação de um método de monitoramento da integridade de uma estrutura metálica baseado em ondas Lamb. Para o monitoramento são utilizadas pastilhas piezoelétricas, em função de seu baixo custo monetário. As pastilhas são utilizadas como atuadores e receptores empregando a propriedade dos materiais piezoelétricos que associa a impedância elétrica coma impedância mecânica. O mecanismo da análise parte da criação de um sinal formado por um pulso elétrico no formato de ondas Lamb e sua aplicação em uma pastilha piezoelétrica fixada na estrutura em estudo, causando uma vibração que se propaga ao longo do elemento estrutural. Segue na captação dessa vibração por outra pastilha piezoelétrica também acoplada à estrutura que a converte em um sinal e finaliza na interpretação desse sinal. A onda Lamb que gera o pulso de excitação enviado ao elemento piezoelétrico é uma função Wavelet. A estrutura é monitorada em seu estado íntegro e em seu estado danificado. Com base nos estudos de vibração e uso da Transformada de Wavelet Contínua, comparam-se as leituras de sinais obtidos em ensaios realizados na estrutura íntegra em seguida na estrutura danificada. Utilizando uma métrica que correlaciona essas leituras, definida como Índice de Dano, verifica-se se o método detecta a existência de dano na estrutura. São executados três experimentos consistindo em uma estrutura formada por uma única viga metálica onde são fixados atuadores e receptores em posições variadas. Insere-se um parafuso em sua constituição, com a função de simular o dano. A estrutura contendo o parafuso configura seu estado íntegro e quando o parafuso é retirado da estrutura, tem-se o estado danificado. Os resultados dos ensaios permitem a avaliação qualitativa da detecção, em função da distância relativa à posição do dano. Também se utiliza um acelerômetro como receptor, visando obter um fator de comparação para os resultados obtidos. Decorrente da quantidade de dados observados se utiliza um tratamento estatístico com medidas resumo e dispersões para a análise. Conclui-se que a metodologia apresentada utilizando a técnica das ondas Lamb em conjunto com a aplicação do Índice de Dano produz resultados satisfatórios e pode ser utilizada como uma alternativa na interpretação de sinais onde o objetivo é a detecção de danos, visto que a metodologia foi capaz indicar a existência do dano independente da sua posição na estrutura proposta. / This work aims at the study and application of a method of monitoring the integrity of a metal structure based on Lamb waves. For monitoring piezoelectric pads are used, in function on your low monetary cost. The pellets are used as actuators and receivers using the property of piezoelectric materials that associates the electrical impedance with mechanical impedance. The analysis part of the creation of a sign consisting of an electrical pulse in the Lamb waves and your format application in a piezoelectric structure mounted insert in study, causing a vibration that propagate along the structural element. Follows on the uptake of this vibration for piezoelectric other pad also coupled to the structure that converts it into a signal and terminates in the interpretation of this signal. The Lamb wave that generates the excitation pulse sent to the piezoelectric element is a Wavelet function. The structure is monitored in your healthy state and in your damaged state. Based on studies of vibration and use of Continuous Wavelet transform, compare the readings of signals obtained in trials conducted in full structure then the structure damaged. Using a metric that correlates these readings, defined as Damage index, the method detects the existence of damage to the structure. Three experiments are performed. The experiments consisting in the analysis of a structure formed by a single metal beam where actuators and receptors are disposed in various positions. Was inserted a screw in your Constitution, with the function to simulate the damage. The structure containing the screw configures your healthy state and when the bolt is removed from the structure, has been damaged. The results of the tests allow the qualitative evaluation of the discovery, on the basis of distance on the position of the damage. Also uses an accelerometer as a receiver, in order to obtain a comparison factor to the results obtained. Due to the amount of observed data was using a statistical summary measures treatment and dispersions for the analysis. It is concluded that the methodology presented using Lamb wave technique in conjunction with the application of the index of damage produces satisfactory results, and can be used as an alternative in the interpretation of signs where the goal is the detection of damage, Since the methodology was able to indicate the existence of damage regardless of your position in the proposed structure.
219

Estimativas para a elasticidade-preço da demanda por produtos siderúrgicos no Brasil

Lavorato, Marcus Vinícius Leal 13 May 2010 (has links)
Submitted by Marcus Lavorato (marcus.lavorato@fgv.br) on 2010-08-27T18:27:02Z No. of bitstreams: 1 Dissertação Mestrado Profissional - Marcus Lavorato - Versão Final.docx: 227127 bytes, checksum: f67a5b6b982cbe7333e06ab085f6206a (MD5) / Approved for entry into archive by Gisele Gammaro(gisele.gammaro@fgv.br) on 2010-08-27T20:40:04Z (GMT) No. of bitstreams: 1 Dissertação Mestrado Profissional - Marcus Lavorato - Versão Final.docx: 227127 bytes, checksum: f67a5b6b982cbe7333e06ab085f6206a (MD5) / Made available in DSpace on 2010-08-30T12:23:32Z (GMT). No. of bitstreams: 1 Dissertação Mestrado Profissional - Marcus Lavorato - Versão Final.docx: 227127 bytes, checksum: f67a5b6b982cbe7333e06ab085f6206a (MD5) Previous issue date: 2010-05-13 / This paper estimates the price elasticity demand for steel in Brazil from aggregated and disaggregated data of the steel industry. The results using disaggregated panel data suggest the existence of an aggregation bias in the estimation using aggregated data, and these bias would underestimate the price elasticity of the steel sector. In order to compare the relations between the price elasticities of long and short term, dynamic heterogeneous panel were estimated by Mean Group and Pooled Mean Group estimators. It’s important to highlight that, according to the author knowledge, this is the first study to use panel data estimation for demand price elasticity to steel products in Brazil, in a manner to control for the heterogeneity across different steel products. / Essa dissertação apresenta estimativas para a elasticidade-preço da demanda por aço no Brasil, a partir de dados agregados e desagregados da indústria siderúrgica. Os resultados das estimativas a partir do painel com dados desagregados sugerem que existe um viés de agregação nas estimativas já realizadas a partir de dados agregados, e esse viés subestimaria a elasticidade-preço do setor siderúrgico. Com a finalidade de comparar as relações entre as elasticidades-preços de curto e longo prazo foram estimados painéis heterogêneos dinâmicos, através de estimadores Mean Group (MG) e Pooled Mean Group (PMG). É importante ressaltar que, de acordo com o conhecimento do autor, este é o primeiro estudo a usar estimação em painel para estimação da elasticidade-preço da demanda por produtos siderúrgicos no Brasil, dessa forma, controlando a estimativa pela heterogeneidade entre os tipos de aço.
220

Characterization of Different Slags for Bulk Geotechnical Applications

Logeshwari, J January 2017 (has links) (PDF)
Generation of wastes in the form of liquid, solid or gas is inevitable in any industry.Industrial Solid Waste is the waste that is generated from an industrial or manufacturing process and includes the waste generated from non-manufacturing activities as well.Most of these wastes fall under the category of Ashes, Slagsor Sludges. For the present work, three types of secondary lead slag, two types of granulated blast furnace slag (GBS) or iron slag and four types of steel slags were procured and studied.An elaborate study on various characteristics of the slags has been performed. Based on the results, all the possible applications for the individual slags are considered. The performance of the secondary lead slag as an embankment material was analyzed. The slope stability for various conditionswas analyzed using Geo5 and experimentally determined strength parameters. It was found that the material can be used safely for embankment constructions.The CBR values were very good in the range for both GBS and steel slag,thus repeated load triaxial test are done to determine the resilient modulus. k1-k3model was adopted and the regression coefficients were determined. Based on the results the pavement design is done using KENPAVE software. An exercise has been performed to determine the quantity of the conventional material that could be saved, considering the type and size of the pavement. For the aggregate sized steel slag, the tests were done to find the suitability of the material for various applications like, as railway ballast, concrete aggregate, gabion and rip rap stones. And the tests result shows the material to be suitable for these applications and is expected to perform well. Study on morphological parameters reveals that the size and gradation of any material plays an important role in its mechanical behavior, however in the case of slags, this could be tailor made by using appropriate crushers, as per the requirements.

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