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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.
11

Integrating remotely sensed hydrologic parameters into an index of sediment connectivity

Ahlmer, Anna-Klara January 2017 (has links)
The expected increase in precipitation and temperature in Scandinavia, and especially short-time heavy precipitation, will increase the frequency of flooding. Urban areas are the most vulnerable, and specifically, the road infrastructure. The accumulation of large volumes of water and sediments on road-stream intersections gets severe consequences for the road drainage structures. The need for a tool to identify characteristics that impacts the occurrence of flooding, and to predict future event is thus essential. This study integrates the spatial and temporal soil moisture properties into the research about flood prediction methods. Soil moisture data is derived from remote sensing techniques, with focus on the soil moisture specific satellites ASCAT and SMOS. Furthermore, several physical catchments descriptors (PCDs) are used to identify catchment characteristics that are prone to flooding and an inventory of current road drainage facilities are conducted. Finally, the index of sediment connectivity (IC) by Cavalli, Trevisani, Comiti, and Marchi (2013) is implemented to assess the flow of water and sediment within the catchment. A case study of two areas in Sweden, Västra Götaland and Värmland, that was affected by severe flooding in August 2014 are included. The results show that the method with using soil moisture satellite data is promising for the inclusion of soil moisture data into estimations of flooding and the index of sediment connectivity. / De förväntade ökningarna i nederbörd och temperatur i Skandinavien, och speciellt extrem korttidsnederbörd, kommer att öka frekvensen av översvämningar. Urbana områden är de mest sårbara, och speciellt väginfrastrukturen. Ackumuleringen av stora volymer av vatten och sediment där väg och vattendrag möts leder till allvarliga konsekvenser för dräneringskonstruktionerna. Behovet av ett verktyg för att identifiera egenskaper som påverkar förekomsten av översvämningar, och för att förutsäga framtida händelser är väsentligt. Studien integrerar markfuktighet både rumsligt och tidsmässigt i forskningen om metoder för översvämningsrisker. Markfuktighetsdata är inkluderat från fjärranalysteknik, med fokus på de specifika satelliterna för markfuktighet, ASCAT och SMOS. Vidare är flertalet faktorer (PCDs) inkluderade för att identifiera egenskaper i avrinningsområden som är benägna till översvämning samt en inventering av nuvarande vägdräneringskonstruktioner. Slutligen är ett index med sediment connectivity (Cavalli et al., 2013) implementerat för att se flödet av vatten och sediment inom avrinningsområdet. En fallstudie med två områden i Sverige, Västra Götaland och Värmland, som drabbades av allvarliga översvämningar i augusti 2014 är inkluderat. Resultaten visar att metoden att använda markfuktighet från satellitdata är lovande för inkludering i uppskattningar av översvämningsrisk och i indexet med sediment connectivity.
12

Avaliação da estabilidade, capacidade e implantação de práticas lean em obras de infraestrutura e pavimentação viária

Freitas, Saulo Joaquim de January 2015 (has links)
O setor da construção civil é conhecido pela grande incidência de perdas em seus processos, o que tem levado ao crescente uso de práticas baseadas nos sistemas de produção enxuta. Este trabalho apresenta a avaliação da estabilidade e capacidade dos processos, bem como o uso de práticas enxutas em uma obra de pavimentação viária. Inicialmente, a avaliação da estabilidade e capacidade foi realizada por meio do mapeamento do fluxo de valor do estado atual e do desenvolvimento e coleta de indicadores associados aos 4M (Material, Mão-deobra, Máquina e Método). Os resultados indicaram que todos os cinco indicadores avaliados foram estáveis, porém apenas um indicador demonstrou capacidade de atender os parâmetros do cliente. Com base nessa avaliação, foram adotadas ações para redução de perdas e melhora da estabilidade e capacidade dos processos, por meio do uso de práticas enxutas, aplicadas em uma segunda obra com características similares à anterior. As práticas usadas foram: i) Mudança e melhoria de alguns processos construtivos; ii) implantação de ferramenta 5S no canteiro de obras; iii) criação e implantação de dispositivos poka-yokes, iv) aplicação de dispositivo visual de comunicação do tipo andon; v) planejamento de entrega de materiais just-in-time. Nessa segunda obra, os indicadores se mantiveram estáveis, mas foi percebida uma melhora quanto à capacidade destes indicadores em atender os parâmetros exigidos. Apenas o indicador de mão-de-obra turn over não foi capaz de atender a meta definida pela empresa. / The Building Sector is known for high incidence of wastes in its process. This characteristic has been motivating the operators to use some practices based on Lean Production Systems. This paper presents an evaluation of the stability and capacity of Lean Construction concepts in a road construction work. The evaluation of the stability and capacity was realized mapping the current state value stream and the collection of indicators associated with the 4M (Material Hand labor, Machine and Method) The results indicated that all seven indicators measured were stable, but only an indicator of the seven evaluated was considered capable. Based on this evaluation, actions were taken to improve the stability and capacity through the use of lean practices, applied in a second work with similar characteristics to the previous. The practices used were: i) improving / changing some construction processes, ii) 5S tool deployment on construction of works iii) creation and implementation of poka-yokes devices, iv) application of visual tool of andon type communication, v) delivery planning materials within the just-in-time concept. In this second work the indicators remained stable, but a great improvement was perceived, related to the ability of the indicators to meet the required parameters. Only the hand labor turnover indicator was not able to meet the target set by the company.
13

Avaliação da estabilidade, capacidade e implantação de práticas lean em obras de infraestrutura e pavimentação viária

Freitas, Saulo Joaquim de January 2015 (has links)
O setor da construção civil é conhecido pela grande incidência de perdas em seus processos, o que tem levado ao crescente uso de práticas baseadas nos sistemas de produção enxuta. Este trabalho apresenta a avaliação da estabilidade e capacidade dos processos, bem como o uso de práticas enxutas em uma obra de pavimentação viária. Inicialmente, a avaliação da estabilidade e capacidade foi realizada por meio do mapeamento do fluxo de valor do estado atual e do desenvolvimento e coleta de indicadores associados aos 4M (Material, Mão-deobra, Máquina e Método). Os resultados indicaram que todos os cinco indicadores avaliados foram estáveis, porém apenas um indicador demonstrou capacidade de atender os parâmetros do cliente. Com base nessa avaliação, foram adotadas ações para redução de perdas e melhora da estabilidade e capacidade dos processos, por meio do uso de práticas enxutas, aplicadas em uma segunda obra com características similares à anterior. As práticas usadas foram: i) Mudança e melhoria de alguns processos construtivos; ii) implantação de ferramenta 5S no canteiro de obras; iii) criação e implantação de dispositivos poka-yokes, iv) aplicação de dispositivo visual de comunicação do tipo andon; v) planejamento de entrega de materiais just-in-time. Nessa segunda obra, os indicadores se mantiveram estáveis, mas foi percebida uma melhora quanto à capacidade destes indicadores em atender os parâmetros exigidos. Apenas o indicador de mão-de-obra turn over não foi capaz de atender a meta definida pela empresa. / The Building Sector is known for high incidence of wastes in its process. This characteristic has been motivating the operators to use some practices based on Lean Production Systems. This paper presents an evaluation of the stability and capacity of Lean Construction concepts in a road construction work. The evaluation of the stability and capacity was realized mapping the current state value stream and the collection of indicators associated with the 4M (Material Hand labor, Machine and Method) The results indicated that all seven indicators measured were stable, but only an indicator of the seven evaluated was considered capable. Based on this evaluation, actions were taken to improve the stability and capacity through the use of lean practices, applied in a second work with similar characteristics to the previous. The practices used were: i) improving / changing some construction processes, ii) 5S tool deployment on construction of works iii) creation and implementation of poka-yokes devices, iv) application of visual tool of andon type communication, v) delivery planning materials within the just-in-time concept. In this second work the indicators remained stable, but a great improvement was perceived, related to the ability of the indicators to meet the required parameters. Only the hand labor turnover indicator was not able to meet the target set by the company.
14

Avaliação da estabilidade, capacidade e implantação de práticas lean em obras de infraestrutura e pavimentação viária

Freitas, Saulo Joaquim de January 2015 (has links)
O setor da construção civil é conhecido pela grande incidência de perdas em seus processos, o que tem levado ao crescente uso de práticas baseadas nos sistemas de produção enxuta. Este trabalho apresenta a avaliação da estabilidade e capacidade dos processos, bem como o uso de práticas enxutas em uma obra de pavimentação viária. Inicialmente, a avaliação da estabilidade e capacidade foi realizada por meio do mapeamento do fluxo de valor do estado atual e do desenvolvimento e coleta de indicadores associados aos 4M (Material, Mão-deobra, Máquina e Método). Os resultados indicaram que todos os cinco indicadores avaliados foram estáveis, porém apenas um indicador demonstrou capacidade de atender os parâmetros do cliente. Com base nessa avaliação, foram adotadas ações para redução de perdas e melhora da estabilidade e capacidade dos processos, por meio do uso de práticas enxutas, aplicadas em uma segunda obra com características similares à anterior. As práticas usadas foram: i) Mudança e melhoria de alguns processos construtivos; ii) implantação de ferramenta 5S no canteiro de obras; iii) criação e implantação de dispositivos poka-yokes, iv) aplicação de dispositivo visual de comunicação do tipo andon; v) planejamento de entrega de materiais just-in-time. Nessa segunda obra, os indicadores se mantiveram estáveis, mas foi percebida uma melhora quanto à capacidade destes indicadores em atender os parâmetros exigidos. Apenas o indicador de mão-de-obra turn over não foi capaz de atender a meta definida pela empresa. / The Building Sector is known for high incidence of wastes in its process. This characteristic has been motivating the operators to use some practices based on Lean Production Systems. This paper presents an evaluation of the stability and capacity of Lean Construction concepts in a road construction work. The evaluation of the stability and capacity was realized mapping the current state value stream and the collection of indicators associated with the 4M (Material Hand labor, Machine and Method) The results indicated that all seven indicators measured were stable, but only an indicator of the seven evaluated was considered capable. Based on this evaluation, actions were taken to improve the stability and capacity through the use of lean practices, applied in a second work with similar characteristics to the previous. The practices used were: i) improving / changing some construction processes, ii) 5S tool deployment on construction of works iii) creation and implementation of poka-yokes devices, iv) application of visual tool of andon type communication, v) delivery planning materials within the just-in-time concept. In this second work the indicators remained stable, but a great improvement was perceived, related to the ability of the indicators to meet the required parameters. Only the hand labor turnover indicator was not able to meet the target set by the company.
15

Ekonomické hodnocení projektů silniční infrastruktury v České republice a na Slovensku / Economic Evaluation of Projects in Road Infrastructure in the Czech Republic and Slovakia

Čajová, Mária January 2018 (has links)
This diploma thesis deals with the problems of economic evaluation in road infrastructure projects in the Czech Republic and Slovakia. In the analytical part the methodology in both countries is solved, diversity is analyzed and in the end the searched differences are assessed. On the basis of results, recommendations are presented. The practical part is concentrated on the proper differences that are further included in the methodology. The general evaluation of advantages and disadvantages of the economic assessment method and suggestion of possible adjustment of the method in the Czech Republic and in Slovakia had been the result of the work.
16

Análisis de interferencias para movimiento de tierras en las infraestructuras viales en el Perú para prevenir los retrabajos en la etapa de planeamiento, mediante la Metodología de Gestión BIM. Caso de estudio, Camino Vecinal Puente Techin – Cruce Chirimoyo, Distrito de Querocotillo- Provincia Cutervo-Cajamarca tramo km 0+000 al 15+000 / Analysis of interferences in road infrastructures in Perú to prevent re-works in the planning stage, through the bim management methodology

Bastidas Cristobal, Joseph Bryan, Herrera Araujo, Jerson George 11 June 2020 (has links)
En la siguiente investigación, se llevó a cabo la implementación de la Gestión BIM (Building Information Modeling) en la etapa de planeamiento del proyecto vial , MEJORAMIENTO CAMINO VECINAL PUENTE TECHIN – CRUCE CHIRIMOYO, DISTRITO DE QUEROCOTILLO- PROVINCIA CUTERVO-CAJAMARCA KM 0+000 AL 15+000, mediante uso de herramientas (softwares) BIM para el diseño y análisis, con el objetivo localizar las interferencias y prevenir los retrabajos, de acuerdo a los resultados obtenidos se propuso posibles soluciones a estas interferencias, las cuales fueron debatidas mediante una Gestión Colaborativa como es el caso de la Gestión BIM para proponer diversas soluciones viales para el desarrollo optimo del Proyecto. La finalidad del proyecto es mejorar los procesos en los proyectos de infraestructura vial mediante la Gestión BIM, ya que en el Perú actualmente no se está aplicando este concepto, tampoco existe una norma que garantice el uso de esta herramienta, sin embargo; en los países europeos, Estados Unidos y Canadá, entre otros, es necesario para garantizar el buen desarrollo y calidad del proyecto. La importancia de las obras viales es importante para el crecimiento del país, porque estas vías de comunicación tienen un papel importante en la sociedad, por lo que se movilizan importantes mercaderías y bienes, así como la comunicación entre personas. Es por eso que el proceso de este tipo de infraestructura se puede hacer de la mejor manera posible, con el objetivo de entregar un producto de buena calidad para el beneficio de todos los involucrados. / The following investigation was carried out to implement the BIM Management (Building Information Modeling) in the planning stage of the road project, MEJORAMIENTO CAMINO VECINAL PUENTE TECHIN – CRUCE CHIRIMOYO, DISTRITO DE QUEROCOTILLO- PROVINCIA CUTERVOCAJAMARCA KM 0+000 AL 15+000, through the use of BIM tools (software) for the design and analysis, in order to locate the interference and prevent rework, according to the results obtained, possible solutions to these interferences must be proposed, which should be be discussed through a Collaborative Management such as the BIM Management to propose a road solution for the optimal development of the Project. The purpose of the project is to improve the processes in road infrastructure projects by BIM Management, as in Peru currently not being implemented this concept, nor is there a standard that ensures the use of this tool, however; in European countries, the United States and Canada, among others, necessary to ensure the proper development and quality of the project. The importance of road works is important for the growth of the country, because these roads have an important role in society, so important commodities and goods move as well as communication between people. That is why the process of this type of infrastructure can be done in the best possible way, with the aim of delivering a good quality product for the benefit of all involved. / Tesis
17

Integrating remotely sensed hydrologic parameters into an index of sediment connectivity

Almer, Anna-Klara January 2017 (has links)
The expected increase in precipitation and temperature in Scandinavia, and especially short-time heavy precipitation, will increase the frequency of flooding. Urban areas are the most vulnerable, and specifically, the road infrastructure. The accumulation of large volumes of water and sediments on road-stream intersections gets severe consequences for the road drainage structures. The need for a tool to identify characteristics that impacts the occurrence of flooding, and to predict future event is thus essential. This study integrates the spatial and temporal soil moisture properties into the research about flood prediction methods. Soil moisture data is derived from remote sensing techniques, with focus on the soil moisture specific satellites ASCAT and SMOS. Furthermore, several physical catchments descriptors (PCDs) are used to identify catchment characteristics that are prone to flooding and an inventory of current road drainage facilities are conducted. Finally, the index of sediment connectivity (IC) by Cavalli, Trevisani, Comiti, and Marchi (2013) is implemented to assess the flow of water and sediment within the catchment. A case study of two areas in Sweden, Västra Götaland and Värmland, that was affected by severe flooding in August 2014 are included. The results show that the method with using soil moisture satellite data is promising for the inclusion of soil moisture data into estimations of flooding and the index of sediment connectivity. / De förväntade ökningarna i nederbörd och temperatur i Skandinavien, och speciellt extrem korttidsnederbörd, kommer att öka frekvensen av översvämningar. Urbana områden är de mest sårbara, och speciellt väginfrastrukturen. Ackumuleringen av stora volymer av vatten och sediment där väg och vattendrag möts leder till allvarliga konsekvenser för dräneringskonstruktionerna. Behovet av ett verktyg för att identifiera egenskaper som påverkar förekomsten av översvämningar, och för att förutsäga framtida händelser är väsentligt. Studien integrerar markfuktighet både rumsligt och tidsmässigt i forskningen om metoder för översvämningsrisker. Markfuktighetsdata är inkluderat från fjärranalysteknik, med fokus på de specifika satelliterna för markfuktighet, ASCAT och SMOS. Vidare är flertalet faktorer (PCDs) inkluderade för att identifiera egenskaper i avrinningsområden som är benägna till översvämning samt en inventering av nuvarande vägdräneringskonstruktioner. Slutligen är ett index med sediment connectivity (Cavalli et al., 2013) implementerat för att se flödet av vatten och sediment inom avrinningsområdet. En fallstudie med två områden i Sverige, Västra Götaland och Värmland, som drabbades av allvarliga översvämningar i augusti 2014 är inkluderat. Resultaten visar att metoden att använda markfuktighet från satellitdata är lovande för inkludering i uppskattningar av översvämningsrisk och i indexet med sediment connectivity.
18

Assessment and relative sustainability of common types of roadside noise barriers

Oltean-Dumbrava, Crina, Miah, Abdul H.S. 18 June 2016 (has links)
Yes / There is increasing legislative and public pressure for the design and build of road infrastructure schemes to achieve better sustainability performance. Roadside noise barriers (RNBs) form a major part of the growing road infrastructure system in mitigating undesirable road noise to impacted communities. However, the relative sustainability of common RNBs is little understood in the research and industry literature. This makes it difficult for stakeholders to make informed decisions with regards to the sustainable design and procurement of RNBs. This paper presents nowel research carried out to assess and rank the relative sustainability of 13 RNB types using three multi criteria analysis (MCA) techniques, i.e. Simple Additive Weighting (SAW), Preference Ranking Organisation MeTHod for Enrichment Evaluations (PROMETHEE), and Elimination et Choice Translating Reality (ELECTRE III). The paper concludes that the presented sustainability rankings of the main RNB types from least sustainable to most sustainable will support the relevant stakeholders, involved in the planning, design, and procurement stages, to evaluate the sustainability of RNB options as either part of a large highways scheme or standalone project. The presented results will save significant analysis time and costs in cases whereby it is unfeasible to conduct MCAs. The presented sustainability asssessment methodology may also provide the basis for an industry sustainability certification sceheme and in turn support advancing the sustainability transport agenda. / FP7 Quiesst research grant funded by the EU.
19

Road Infrastructure Readiness for Autonomous Vehicles

Tariq Usman Saeed (6992318) 15 August 2019 (has links)
Contemporary research indicates that the era of autonomous vehicles (AVs) is not only inevitable but may be reached sooner than expected; however, not enough research has been done to address road infrastructure readiness for supporting AV operations. Highway agencies at all levels of governments seek to identify the needed infrastructure changes to facilitate the successful integration of AVs into the existing roadway system. Given multiple sources of uncertainty particularly the market penetration of AVs, agencies find it difficult to justify the substantial investments needed to make these infrastructure changes using traditional value engineering approaches. It is needed to account for these uncertainties by doing a phased retrofitting of road infrastructure to keep up with the AV market penetration. This way, the agency can expand, defer, or scale back the investments at a future time. This dissertation develops a real options analysis (ROA) framework to address these issues while capturing the monetary value of investment timing flexibility. Using key stakeholder feedback, an extensive literature review, and discussions with experts, the needed AV-motivated changes in road infrastructure were identified across two stages of AV operations; the transition phase and the fully-autonomous phase. For a project-level case study of a 66-mile stretch of Indiana’s four-six lane Interstate corridor, two potential scenarios of infrastructure retrofitting were established and evaluated using the net present value (NPV) and ROA approaches. The results show that the NPV approach can lead to decisions at the start of the evaluation period but does not address the uncertainty associated with AV market penetration. In contrast, ROA was found to address uncertainty by incorporating investment timing flexibility and capturing its monetary value. Using the dissertation’s framework, agencies can identify and analyze a wide range of possible scenarios of AV-oriented infrastructure retrofitting to enhance readiness, at both the project and network levels.
20

Consideration of life cycle energy use and greenhouse gas emissions for improved road infrastructure planning

Miliutenko, Sofiia January 2016 (has links)
Global warming is one of the biggest challenges of our society. The road transport sector is responsible for a big share of Greenhouse Gas (GHG) emissions, which are considered to be the dominant cause of global warming. Although most of those emissions are associated with traffic operation, road infrastructure should not be ignored, as it involves high consumption of energy and materials during a long lifetime. The aim of my research was to contribute to improved road infrastructure planning by developing methods and models to include a life cycle perspective. In order to reach the aim, GHG emissions and energy use at different life cycle stages of road infrastructure were assessed in three case studies using Life Cycle Assessment (LCA). These case studies were also used for development of methodology for LCA of road infrastructure. I have also investigated the coupling of LCA with Geographic Information Systems (GIS) and the possibility to integrate LCA into Environmental Impact Assessment (EIA) and Strategic Environmental Assessment (SEA). The results of the first case study indicated that operation of the tunnel (mainly, lighting and ventilation) has the largest contribution in terms of energy use and GHG emissions throughout its life cycle. The second case study identified the main hotspots and compared two methods for asphalt recycling and asphalt reuse. The results of the third case study indicated that due to the dominant contribution of traffic to the total impact of the road transport system, the difference in road length plays a major role in choice of road alternatives during early planning of road infrastructure. However, infrastructure should not be neglected, especially in the case of similar lengths of road alternatives, for roads with low volumes of traffic or when they include bridges or tunnels. This thesis contributed in terms of foreground and background data collection for further LCA studies of road infrastructure. Preliminary Bill of Quantities (BOQ) was identified and used as a source for site-specific data collection. A new approach was developed and tested for using geological data in a GIS environment as a data source on earthworks for LCA. Moreover, this thesis demonstrated three possible ways for integrating LCA in early stages of road infrastructure planning. / <p>QC 20160329</p>

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