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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.
31

Přepravy nebezpečných látek na území České republiky / Transport of Dangerous Substances in the Czech Republic

VANDAS, David January 2014 (has links)
The topic of the diploma written assignment is "Transport of Dangerous Substances in the Czech Republic" and it was chosen for elaboration of the wholesome view on the road, train, ship and plane transportation of the hazardous materials and mixtures. These transportations represent a possible risk of damage to life, health, property or environment for the society. Hazardous materials and mixtures nowadays are being transported in large measures and there is an assumption in the future that the volume of the transported hazardous materials and mixtures will increase. For elaboration of this written assignment three hypothesis were given: a) Legal regulations of the European Union and the Czech Republic solve the problematic of the transportation of hazardous materials and mixtures well enough. b) The public has enough information about the transportation of the hazardous chemical substances or mixtures. c) People that work in the field of the transportation of hazardous materials or mixtures are well informed about the transportation of hazardous chemical substances or mixtures. For determining whether the legal regulations solve the problematic of the transportation of hazardous materials and mixtures well enough the literary sources which deal with this issue, legal regulations of the Czech Republic and the European Union and other international agreements were used. After working through these sources it was found out that the international, the EU and Czech legal regulations or agreements solve this issue well enough and emphasis is given on convergence of legal regulations of all transportations. Implementation of international agreements and legal regulations of the European Union into the legal regulations of the Czech Republic happens in the present time very fast and without failures. For figuring out the awareness of the public and awareness of the people working in the field of the transportation of hazardous materials and mixtures for the diploma written assignment on the topic of "The Transportation of Hazardous Materials and Mixtures on the Territory of the Czech Republic" there was a quantitative research made. The quantitative research was made with the help of handed out questionnaires. The public was represented by the employees of the Regional Municipalities of the Czech Republic. Both of the groups were given the same questionnaires. The results of the questionnaire research were evaluated, expressed in percentage and statistically assessed. For the statistical assessment the double selection T-test was used to find out whether the difference between the assessed groups is statistically important. People working in the transportation of hazardous substances and mixtures have sufficient information which was confirmed by the questionnaire research. By the made statistical assessment it was found out that the difference between the groups is statistically significant and so the public does not have sufficient information related to the transportation of hazardous substances and mixtures. Due to the results of the questionnaire research and mainly that the hypothesis b) - The public has enough information about the transportation of hazardous chemical substances or mixtures was not confirmed. In the conclusion of the written assignment there are a couple of suggestions for improvement of the awareness of the public. For example as a part of education at primary and high schools and training schools where this education is already running as a part of The Protection of Human during Incidents. This education has been going on since 2003. And that is why the older people in the public are not well met with this issue and they should be introduced to it by for example a media campaign by means of short TV spots on public television channels or by means of spots that already the Independent BESIP Department of the Ministry of Transportation makes up. These spots are called Besipky.
32

Aplicação da teoria de análise de rede social e proposta de um esquema conceitual para desenvolvimento de uma infraestrutura de dados espaciais para transporte rodoviário de produtos perigosos. / Applications of the theory social network analysis and propose of a conceptual scheme of a spatial data infrastructures to road transportation of dangerous goods.

Janaina Bezerra Silva 10 December 2013 (has links)
Os dados espaciais têm sido utilizados para o monitoramento ambiental de consequências de acidentes com produtos químicos no transporte de produtos perigosos. A Infraestrutura de Dados Espaciais (IDE), que foi criada para a disponibilização e uso de dados espaciais, esbarra na ausência de políticas para dar suporte a essa realização. O objetivo principal deste trabalho é explorar o uso da teoria de Análise de Rede Social (ARS) para diagnosticar a articulação entre as organizações do setor, e discutir as políticas e acordos institucionais vigentes e criar um esquema conceitual de uma IDE para gerenciamento de acidentes relacionados ao Transporte Rodoviário de Produtos Perigosos (TRPP). Neste contexto, esta pesquisa identificou as instituições que tratam do tema TRPP, para que informações sobre o interesse no uso e compartilhamento de dados espaciais através de uma IDE pudessem ser coletadas através de entrevistas, e desta forma, consolidadas. As entrevistas foram aplicadas de forma presencial em 39 instituições. A aplicação da teoria Análise de Rede Social (ARS) pôde diagnosticar o fluxo dos dados entre as instituições através da representação gráfica das redes de disponibilização e utilização de dados espaciais entre as organizações participantes. A partir de então, foram analisados e discutidos os acordos vigentes para compartilhamento de dados espaciais. Os resultados compilados permitiram propor um esquema conceitual de uma IDE para apoio a desastres envolvendo o TRPP, para, então, prover a elaboração de metodologia para o suporte ao diagnóstico da articulação entre os diversos atores de uma IDE. A finalidade é a possível a formulação de políticas para disponibilização de dados espaciais para tomada de decisões preventivas e de enfrentamento de desastres. Os resultados indicaram que as 39 instituições compartilham dados espaciais entre si, ainda que nem sempre por acordos formais preestabelecidos. Constatou-se ainda que há um grande anseio por parte das instituições que fazem o gerenciamento de acidentes envolvendo o TRPP para que haja mecanismos legais para compartilhamento de dados estruturantes para planejamento territorial - para que o uso desses dados possa auxiliar na preparação, prevenção, gerenciamento e socorro imediato aos incidentes que envolvem o TRPP. / Spatial data have been used for environmental monitoring of chemical accidents on the road transportation of dangerous goods. The Spatial Data Infrastructure (SDI) has been created to availability and use of spatial data, however, it emphasizes that there are no policies to support this realization. The main aim of this work is to create a conceptual scheme of a Spatial Data Infrastructure (SDI) for management of transport of Dangerous Goods by road, focusing on the political context. It was identified the institutions that deal with the subject of road transportation of hazardous materials, Moreover the interviews could be consolidated. The interviews were administered by face, in 39 institutions. Interview data were ran in software UCINET, 2000 to obtain metrics related to centrality measures. The application of the theory of Social Network Analysis (ARS) could recognize the flow of data between institutions through the enrolled institutions. Furthermore, it was analyzed the network availability and use aspects of spatial data sharing between the organizations. Besides, the compiled results allowed to propose a conceptual scheme of a SDI to support technological disasters with road transportation of hazardous materials throw the SNA theory applied to investigation of spatial data sharing between different stakeholders to make prevention and risk management of the sector. Therefore, the analysis of the theory of Social Network Analysis (ARS) found that 39 (thirty-nine) institutions share spatial data between themselves, but not always in formal agreements previously established. It was further observed that there is a great desire on the part of the institutions that make the management of the accidents of this kind of transportation mode, so there are legal frameworks for data sharing for land cover uses, as a result the use of such data can be shared between different stakeholders to assist the preparedness, mitigation, response and recovery from incidents related to road dangerous goods transportation.
33

Uplatnění mezinárodní silniční přepravy v rámci aktivit zasílatelské firmy Transforwarding a.s. / Use of international freight road transportation within forwarding company Transforwarding a.s.

Průchová, Nikola January 2011 (has links)
The goal of this diploma thesis is to give a comprehensive overview about the use of international freight road transportation within forwarding company Transforwarding a.s. and also to suggest suitable solution for their future system of organizing international freight road transportation within a new area.
34

On the electrification of road transportation – A review of the environmental, economic, and social performance of electric two-wheelers

Weiss, Martin, Dekker, Peter, Moro, Alberto, Scholz, Harald, Patel, Martin K. 11 November 2020 (has links)
Electrification is widely considered as a viable strategy for reducing the oil dependency and environmental impacts of road transportation. In pursuit of this strategy, most attention has been paid to electric cars. However, substantial, yet untapped, potentials could be realized in urban areas through the large-scale introduction of electric two-wheelers. Here, we review the environmental, economic, and social performance of electric two-wheelers, demonstrating that these are generally more energy efficient and less polluting than conventionally-powered motor vehicles. Electric two-wheelers tend to decrease exposure to pollution as their environmental impacts largely result from vehicle production and electricity generation outside of urban areas. Our analysis suggests that the price of e-bikes has been decreasing at a learning rate of 8%. Despite price differentials of 5000 ± 1800 EUR2012 kW h−1 in Europe, e-bikes are penetrating the market because they appear to offer an apparent additional use value relative to bicycles. Mid-size and large electric two-wheelers do not offer such an additional use value compared to their conventional counterparts and constitute niche products at price differentials of 700 ± 360 EUR2012 kW−1 and 160 ± 90 EUR2012 kW−1, respectively. The large-scale adoption of electric two-wheelers can reduce traffic noise and road congestion but may necessitate adaptations of urban infrastructure and safety regulations. A case-specific assessment as part of an integrated urban mobility planning that accounts, e.g., for the local electricity mix, infrastructure characteristics, and mode-shift behavior, should be conducted before drawing conclusions about the sustainability impacts of electric two-wheelers.
35

Sustainable Supply Chain Management through the integration of IoT: Road Transportation

Al-Majidi, Samsul Alam January 2022 (has links)
Traditional transport companies usually focus on achieving economies of scale in supply chain management. At the same time, the managers of transport companies aiming to achieve sustainability often do not consider the barriers needed to overcome to achieve a sustainable supply chain. However, due to the increasing demand for sustainable products and business methods, sustainable supply chain management increasingly plays a crucial role in changing and diverting the focus on environmental, social and economic impact. Transport companies around the globe are increasingly aiming to reduce carbon emissions and eliminate biodiversity loss. The sustainability issues with transport in supply chain management have been a critical field of research for decades, and with the integration of technology, new ways of achieving sustainability are possible. This thesis analyses a phenomenon using multiple cases to investigate the barriers transport companies face to adopting IoT. Also, it deals with how communication service providers might be able to offer solutions to the barriers presented in this thesis.  A qualitative method has been used to approach the research topic. The findings will represent the ways of achieving a more efficient and sustainable supply chain, particularly in the transport sector. Interviews were conducted with multiple industry experts. The study aims to identify the barriers to adopting IoT, which can create a sustainable supply chain for transport companies. The results emphasise the barriers transport companies have to deal with internally and externally. Internally a company might struggle to strategise an infrastructural investment, train the existing workforce, and collaborate knowledge share among different departments. Externally, transport companies or communication service providers (CSP) will face limited resources, stakeholders' investment in the IoT ecosystem, demand for IoT and sustainable supply chain, privacy issues, compatibility issues and lack of skilled labour.
36

<b>Safety and mobility improvement of mixed traffic using optimization- And Learning-based methods</b>

Runjia Du (9756128) 11 December 2023 (has links)
<p dir="ltr">Traffic safety and congestion are global concerns. Autonomous vehicles (AVs) are expected to enhance transportation safety and reduce congestion. However, achieving their full potential requires 100% market penetration, a challenging task. This study addresses key issues in mixed traffic environments, where human-driven vehicles (HDVs) and connected autonomous vehicles (CAVs) coexist. A number of critical questions persist: 1) inadequate exploration of human errors (errors originating from non-CAV sources) in mixed traffic; 2): limited focus on information selection and learning efficiency in network-level rerouting, particularly in highly dynamic environments; 3) inadequacy of personalized element driver inputs in motion-planning frameworks; 4) lack of consideration of user privacy concerns.</p><p dir="ltr">With the goal of advancing the existing knowledge in this field and shedding light on these matters, this dissertation introduces multiple frameworks. These frameworks leverage connectivity and automation to improve safety and mobility in mixed traffic, addressing various research levels, including local-level and network-level safety enhancement, as well as network-level and global-level mobility enhancement. With optimization- and learning-based methods implemented (Model Predictive Control, Deep Neural Network, Deep Reinforcement Learning, Transformer model and Federated Learning), frameworks introduced in this dissertation are expected to help highway agencies and vehicle manufacturers improve the safety and efficiency of traffic flow in the mixed-traffic era. Our research findings revealed increased crash-avoidance rates in critical situations, enhanced accuracy in predicting lane changes, improved dynamic rerouting within urban areas, and the implementation of effective data-sharing mechanisms with a focus on user privacy. This research underscores the potential of connectivity and automation to significantly enhance mixed-traffic safety and mobility.</p>
37

<b>Enhancing Highway Safety and Construction Quality Control Through Friction-Based Approaches</b>

Jieyi Bao (19180027) 19 July 2024 (has links)
<p dir="ltr">Pavement friction is fundamental to the safety of road networks. A precise assessment of friction levels is essential for the strategic development of maintenance practices and policies by state highway agencies. Typically, assessments of pavement friction have been conducted individually, focusing on particular segments of roadways. Nevertheless, this approach does not offer a thorough evaluation of roadway friction conditions at the network level. This study combines the Density-Based Spatial Clustering of Applications with Noise (DBSCAN) and the Gaussian Mixture Model (GMM) to evaluate the ratings of pavement friction throughout the entire state’s road system. A dataset oriented towards safety, serving as input for clustering models across various data dimensions, has been established. Through comparative and statistical analyses, six friction performance ratings have been identified and subsequently validated. The findings not only facilitate a deeper comprehension of the interrelations among friction levels, crash impact, and additional factors impacting safety, but also provide substantial insights for the advancement of road safety, management, and development.</p><p dir="ltr">Pavement markings play an essential role in regulating traffic flow and improving traffic safety. Beyond facilitating road safety via visual cues to drivers, the frictional properties of pavement marking surfaces are a pivotal element in safeguarding roadway safety. However, the friction characteristics of pavement marking surfaces have not been sufficiently investigated. Additionally, the integration of glass beads or other particles with pavement markings to enhance reflectivity and retroreflectivity complicates the study of their friction properties compared to bare pavements. To tackle these problems, this research utilizes the British pendulum tester (BPT), the circular track meter (CTM), the dynamic friction tester (DFT), and the three-wheel polishing device (TWPD) to evaluate the friction performance of various pavement markings. Eighteen specimen groups, comprising six types of markings (i.e., waterborne paint, preformed tape, epoxy paint, polyurea paint, MMA paint, and thermoplastics) with various glass beads and particles, were investigated to assess their impact on dry and wet friction, mean profile depth (MPD), and durability. The outcomes of this study serve as valuable resources for advancing safety measures and providing insights into emerging traffic management technologies.</p><p dir="ltr">Currently, there is an absence of established standards or methods for assessing and evaluating the friction characteristics of road markings. This lack of standardization has a pronounced impact on vulnerable road users-motorcyclists, bicyclists, and pedestrians-due to the potential for inadequate friction from road markings. To address the problem, this study has developed five friction levels based on the wet British pendulum number (BPN). Leveraging international standards and practical considerations, a tentative BPN range is advocated for crosswalks, symbols, and letters to enhance the safety of pedestrians and other susceptible road users.</p><p dir="ltr">Friction metrics, like MPD and friction number (FN), have been central to enhancing quality assurance and control (QA/QC) processes in chip seals. These metrics evaluate chip seal performance by examining problems such as aggregate shedding or significant bleeding, potentially leading to lower friction values or surface textures. However, instead of leading to slippery conditions, the loss of aggregate-particularly as a consequence of snow-plow operations-may result in the formation of uneven surface textures. The relationship between increased MPD or FN and enhanced chip seal quality is complex and not easily defined. This study introduces a groundbreaking method utilizing machine learning techniques, designed to improve the QC procedure for chip seals. A hybrid anomaly detection approach was applied to a dataset consisting of 183,794 MPD measurements, each representing the average mean segment depth (MSD) over 20-meter segments, gathered from real-world chip seal projects throughout the six districts managed by INDOT. A two-phase QC process, specifically tailored for chip seal quality assessment, has been developed. Validation analysis performed on four chip seal projects shows a strong concordance between field inspection, friction measurements, and the results predicted using the introduced approach. The developed method sets a foundational chip seal QC procedure, augmenting efficiency in acceptance processes and overall safety through data-driven techniques, while reducing the practitioners' time on site.</p><p dir="ltr">Surpassing the constraints of traditional approaches, this paper develops a series of scientific methodologies for evaluating friction on pavement and pavement marking surfaces through extensive in-field and laboratory experiments. Additionally, it establishes rational and efficient quality control procedures for chip-seal applications. The methodologies and conclusions presented in this paper can assist engineers in Departments of Transportation (DOTs) with ensuring the safety of all stakeholders, including road users, engineers, and construction practitioners. Furthermore, they offer valuable insights for the timely execution of road maintenance activities.</p>
38

Application of value for money assessment in public-private partnerships in the road transport sector : a case of the N4 (East) toll road

Muvirimi, Nyasha 12 1900 (has links)
Thesis (MDF)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The purpose of this research was to understand how value for money (‘VfM’), an important decision pillar in public procurement, is applied in South Africa, and compare the VfM regulated framework with other global practices in the United Kingdom, Canada, Australia, Singapore and Hong Kong. VfM is applied when deciding the most appropriate procurement method that utilises public funds in the most cost effective, equitable and transparent manner. Although VfM is vital in the public sector, it is one of the most misunderstood and controversial procurement aspects. The various actors in public procurement processes tend to complicate this key aspect due to their conflicting objectives in relation to a given project. Chief among these are the political influences on the public managers, which tend to manipulate the procurement choice. Consequently over the years, the VfM assessments performed before selecting a procurement method have not been publicly available, thereby increasing concern on whether VfM is achieved, particularly when involving the private sector through public-private partnership (‘PPP’) arrangements. The study explores the various components of VfM, which are the public sector comparator, risk allocation mechanisms, particularly for the road sector projects, discount rates and post project implementation monitoring systems. More importantly, the research analysed how these various aspects were assessed on procuring the N4 toll road. South African National Road Agency SOC Limited (‘SANRAL’), although it did not have the benefit of a PPP guideline as is the case now, it performed extensive feasibility studies and held a transparent procurement process before selecting the private sector party to the PPP. Interestingly, project that was pre-identified as a PPP procurement model and had political support from both the Mozambique and South African governments from inception in order to make it work. The comparative analysis of the South African PPP framework and the selected global PPP markets revealed that the local VfM guidelines were comparable in most aspects such as the PSC construction and risk management methodologies. However, the South African practices could be further improved with increased transparency incorporated in the procurement process such as the publication of the PPP contract once finalised – a practice common in the developed markets analysed. This will go a long way to increasing acceptance of the PPP procurement model in a market that is tainted with mistrust of same. There is need for the civil servants to be trained on the VfM assessment processes so that such analyses are not limited to PPP-type projects, but to conventionally-procured infrastructure projects for increased accountability and effective use of public funds.
39

ASSESSING THE EFFECTS OF COGNITIVE SECONDARY TASKS AND AUTOMATION TYPE ON CHANGES IN HEART RATE: IMPLICATIONS FOR THE POTENTIAL USE OF NANOTECHNOLOGY

Nade Liang (7044191) 14 August 2019 (has links)
<div>Vehicle automation is developing at a rapid rate worldwide. However, even lower levels of automation, such as SAE Level-1, are expected to reduce drivers’ workload by controlling either speed or lane position. At the same time, however, drivers’ engagement in secondary tasks may make up for this difference in workload displaced by automation. Previous research has investigated the effects of adaptive cruise control (ACC) on driving performance and workload, but little attention has been devoted to Lane Keeping Systems (LKS). In addition, the influence of secondary cognitive tasks on Level-1 driving performance is also not well understood.</div><div><br></div><div>The first goal of this thesis study was to examine the effects of secondary cognitive tasks and driving condition on driving performance. The second goal was to examine the effects of secondary cognitive tasks and driving condition on heart rate related measurements that reflect changes in workload. Both a novel nano-sensor and a commercial ECG sensor were used to measure heart rate. Thus, the third goal was to compare the capability of a nano-sensor in detecting changes in heart rate and heart rate variability with a commercially available ECG sensor. Twenty-five participants drove a simulated vehicle in manual, ACC and LKS driving conditions, while performing a secondary cognitive (N-back) task with varying levels of difficulty.</div><div><br></div><div>Results showed that more difficult cognitive secondary tasks were beneficial to driving performance in that a lower standard deviation of lane departure (SDLD) and a lower standard deviation of vehicle speed (SDVS) were both observed. Heart rate and NASA-TLX workload scores were significantly higher in the most difficult secondary task and in the manual driving conditions. However, heart rate variability measures (SDNN, RMSSD, pNN50, LF Power and HF Power) indicated lower variability under more difficult secondary tasks. This thesis suggests that nanotechnological devices may serve as a potential alternative to other heart rate measuring technology. Limitations in detecting minor heart rate changes between different driving conditions and in heart rate variability measuring were also acknowledged.</div>
40

Problematika vlivu úkapů ropných látek na hutněné asfaltové vrstvy / Resistance to fuel of asphalt mixtures

Koželuhová, Jana January 2013 (has links)
Aim of the Master’s thesis is analysis of problems of the dangerous goods road transportation, especially transport of flammable liquids. It analyses the European Agreement concerning the International Carriage of Dangerous Goods by Road and its special requirements. Thesis also covers road tanker accidents and the removal of leaked petroleum products. In practical portion the work on resistance testing of asphalt mixtures against several types of fuel is presented.

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