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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.
121

5E interactive Notebook with CER Framework Using Sail-Cars

Dunlap, E., Nivens, Ryan A. 01 September 2018 (has links)
No description available.
122

Development of a process for environmental life cycle investigations

Berntsson, Erik, Dimgård, Albin January 2022 (has links)
As a result of increasing interest in sustainable development, the subject of this report is the exploration of methods to analyse the environmental impact of car components. The project is conducted as a case study, and the theory section is a literature study where several scientific articles about life cycle assessment (LCA) and environmental analysis are examined alongside previously performed LCAs, books about the subject, and ISO standards. The ISO14040-series provides a structure for the basic methodology used in this report, both to organise the theory section as well as the resulting process. The theory concludes with a 7-step process for conducting life cycle investigations, primarily for car components. The first step contains the ISO standard’s requirements of defining goal and scope. Steps 2-6 then process the data collection of different phases during the life cycle and the 7th and final step is a compilation and calculation of the data. The developed process aims to provide a fast and simple way of analysing the environmental impact for a product as the development work is progressing. To validate the functionality of the process and to further refine the process, it is used to perform an analysis of energy use and CO2 emissions during the life cycle of an active car bonnet device. This validation includes definitions of goal, scope, functional unit, and a Process Flow Chart in the first step.Steps 2-6 includes the data collection for raw materials, additional processes, use phase, end-of-life, and the transports related to the manufacturing of the investigated product. The last step of the validation is to compile the product’s energy use and CO2 emissions. The study also provides a suggestion for a table, called Life Cycle Eco Data Table, to use when conducting a life cycle investigation using the process, to get an overview of the environmental data. The conclusion is that the developed process is easy to use and aspires to high quality as it is based on scientific research.
123

Design och konstruktion av släpvagnför tävlingsbilar / Design and construction of a trailer for racing cars

Alhifi, Haidar, Samir, Laith January 2015 (has links)
I samband med Transportstyrelsens införande av utökad B-körkortsbehörighet öppnades nya marknader för släpvagnar anpassade för transport av tävlingsbilar, verktyg och reservdelar. Sådana släpvagnar går att införskaffa sig idag på den svenska marknaden, dock är dessa endast anpassade för körkortsbehörigheten BE. Detta projekt utförs på uppdrag av företaget Fredrik Wagner AB, ett företag som designar och konstruerar transportband. Syftet med arbetet var att undersöka och utforska möjligheten för implementering av en ny släpvagnsmodell på den svenska marknaden. Målet med arbetet var att utveckla ett släpvagnskoncept anpassat för utökad B-behörighet, och därefter designa en CAD-modell av konceptet.Information om bilsporten och marknaden samlades in för att definiera och förstå problemet bättre. Därpå utfördes idé- och konceptgenereringsfaser för att hitta lösningar till problemet. Dessa lösningar utvecklades sedan till ett CAD-koncept med hjälp av CAD-programmet Solid Edge.Konstruktionsarbetet begränsades i detta projekt till släpvagnens påbyggnad och dess ingående komponenter. Påbyggnadskonceptet erbjuds i två utföranden, det ena är anpassat för utökad B-behörighet medan det andra är för BE-behörighet. För utökad B-behörighet blev påbyggnadens totala vikt 695 kg medan vikten för BE-behörighet blev 1 005 kg.Släpvagnen är konstruerad för att transportera tävlingsbilar med en vikt på 1 100 kg, det är dock även möjligt att transportera andra bilar med släpvagnen om dessa inte överstiger viktbegränsningen. Eftersom arbetet begränsades till endast påbyggnaden har konstruktionen av ett chassi uteslutits. Chassit kan antigen köpas från någon leverantör eller konstrueras av Fredrik Wagner AB. Hur chassit och påbyggnaden ska monteras ihop är något som utelämnades för vidare arbete. / New markets for trailers designed to transport racing cars, tools and spare parts were opened in conjunction with the Transport Agency´s introduction of the extended B driving license. Such trailers are possible to purchase on the Swedish trailer market today. However, the ones on the market are only suitable for the BE driving license. This project is carried out on behalf of the company Fredrik Wagner AB, which is a company that designs and constructs conveyor belts. The aim of this work was to investigate and explore the possibility of implementing a new trailer model to the Swedish market. The goal of this work was to develop a trailer concept and design a CAD-model of the concept.Information about motorsports was collected to define and to improve the understanding of the problem. In order to find solutions to the defined problem, idea and concept generation phases were conducted. The solutions were then developed into CAD concepts by using the CAD-software Solid Edge.The design and construction in this project was limited to the trailer body and its components only. The trailer body´s concept is offered in two versions, one adapted for the extended B driver´s license while the other is for the BE license. The version for the extended B license got at total weight of 695 kg, while the BE version got a total weight of 1 005 kg.The trailer body was designed to transport racing cars with a weight of 1 100 kg, however, it is possible to transport other cars with the trailer body if these do not exceed the weight limit. Since the work was limited to the trailer body only, the construction of a trailer chassis was excluded. The trailer chassis can either be purchased from a retailer or designed by Frederik Wagner AB. How the trailer chassis and the trailer body should be fitted together was though omitted as further work with the trailer.
124

A Daily Vulnerability in America: Tornadoes on our Highways with a Focus on Controlled Access Highways

Croskery, Craig Douglas 04 May 2018 (has links)
Tornadoes are always dangerous, but inside a motor vehicle they are especially problematic due to an automobile’s smaller size and structure. Tornado fatalities in motor vehicles have not decreased in recent years despite downward trends in total tornado fatalities. Receiving tornado warnings is difficult inside a motor vehicle, particularly when alone in the vehicle. Controlled access highways are also difficult places to find shelter as access is limited to interchanges, while buildings at interchanges may not be able to withstand an intense tornado. Electronic signs and audible messages on mobile communications devices are the most suitable technologies available for reaching motorists. At each interchange, shelters capable of withstanding a violent tornado should be constructed or retrofitted, allowing motorists – and nearby residents – a safe place to shelter nearby. Constructing such shelters will take considerable time and significant cost but will go a long way towards the goal of a Weather-Ready Nation.
125

Need for Speed – A Systems Perspective on the Environmental Cost of High Top Speeds in German Passenger Cars

Chordia, Mudit January 2018 (has links)
Automobiles have evolved from meeting transportation needs of their owners a century ago, to addressing transportation desires of their owners today. They now meet the owner’s desire for status though sign values such as speed, safety, environmental consciousness, sexual desire, freedom, masculinity etc., and are anthropomorphised by creatively invented names. It comes as little surprise that the transport sector alone accounts for nearly a quarter of the global greenhouse gas (GHG) emissions – levels that are further expected to double by 2050. Germany, which is the highest emitter of GHGs in Europe recorded nearly 1 Gt GHG emissions in 2016 alone. Such high concentration of emissions from the German transport sector can in some part be attributed to the autobahn network in Germany – 2/3rd of which have no mandated speed limits, thus encouraging the car manufacturers to design cars that are operation worthy even at speeds of up to 250 km/ h (or higher), that are unrepresentative of real world driving conditions. This thesis aims at quantifying the environmental impact of this design for high top speeds in passenger cars from a systems perspective. This is achieved by using a comparative lifecycle assessment of passenger cars from a cradle-to-grave approach. A number of passenger car specifications are modelled which include a representative base case for a German car, vehicle light-weighting approach through material substitution, and down engineered car. The results of the comparative lifecycle assessment showed that, light-weighting a passenger car through material substitution showed a reduction of between 3 to 9% in impact categories such climate change, particulate matter formation, fossil depletion, human toxicity and terrestrial eco-toxicity as compared to the baseline levels. Higher reductions of nearly 12% and 31%, were observed in the marine eco-toxicity and the metal depletion impact categories respectively. However, there exists potential to reduce up to 40% in all selected environmental impact categories when comparing baseline passenger car to a down engineered one. Further, light-weighting a passenger car through higher material substitution showed an increase in the indirect energy consumption and higher impacts in ten out of the eighteen impact categories, as compared to a lower material substitution option. Thus, an important conclusion drawn from this thesis is that when implementing steps to reduce environmental impacts of passenger cars, shift of burden must be avoided between the lifecycle phases as well as the impact categories.
126

"Auto"-Exploitation: A Marxist Examination of Self-Driving Cars

DuVall, Parker 01 January 2023 (has links) (PDF)
In this thesis, I argue that a neo-Marxist critical theory perspective on self-driving cars shifts critical conversations from risks and benefits to concerns about the commodification of free time necessary for our human experience of autonomy. First, I outline that neo-Marxist perspective by charting the different types of power exercised by a capitalist in order to increase their surplus. I then analyze Karl Marx's conception of time in economic exchange to show that, under capitalism, power is exercised over labor through the commodification of workers' free time. I then introduced Michel Foucault's concept of biopower to transition to the commodification not only of labor but also of bodies. Then, I introduce contemporary German philosopher Byung-Chul Han's concept of psychopolitics as a neo-Marxist critique of the exercise of power over the psyche of individuals in order to increase their surplus. These philosophers' models shift commodification from labor to bodies to information. In the final section, I apply Han's contemporary critique of power dynamics to the case of self-driving cars (SDCs) to show that the technologies they represent may serve to perpetuate the negative implications of a constantly optimizing society: a continuation of commodification of the very conditions of labor. This analysis illuminates an overlooked possible negative implication of this emerging technology, as contemporary literature focuses heavily on the developer of the self-driving cars rather than the user and glosses over possible concerns of alienation of the workers' time itself. I argue that increases in "free time" proposed by the implementation of self-driving cars will inevitably be used for "auto"-exploitation, or, self-exploitation. This thesis will contribute to developing work on the effects self-driving cars have on their users, rather than emphasizing effects on society or our environments.
127

Investigating the use of machine learning in key performance indicatorprediction for User Experience of Connectivity

Skiöld, David, Arora, Shivani January 2022 (has links)
Connectivity has been introduced to the car industry and currently Volvo, amongother automobile companies, currently has cars which are connected to the internetand can share data with external devices or services. However, these connected carsoften face issues with connectivity which is a concern for user quality of experience(QoE). One such issue is the difficulty of knowing how the connection changes over timeand if there are issues with said connectivity. In this work, use of different machinelearning techniques on charged data record (CDR) data is described to forecast thedefined key performance indicators (KPIs) derived from the CDR data. Additionally,use of unsupervised machine learning techniques to detect anomalies in the KPIs isinvestigated. The results show that in case of forecasting models, performance of Longshort term memory (LSTM) model surpasses other models.In case of unsupervisedmachine learning techniques like clustering methods, the performance of K-Means++model is found to be mediocre when evaluated using confusion matrix. / <p>Online</p>
128

Femtosecond CARS Microscopy to characterize lipid droplets in Engineered Adipose Tissue

Rashvand, Shahriar Cyrus January 2018 (has links)
Adipose tissue is a type of connective tissue whose purpose was once thought to be limited to fat storage but is now understood to be a key factor in the pathogenesis of different metabolic diseases, including obesity and type-II diabetes. Adipose tissue consists largely of adipocytes, cells responsible for fat and releasing energy in form of lipids. Different classes of fatty acids, such as saturated and unsaturated have different biological effects on adipocytes. Lipid droplets are the primary organelles in adipocytes that store these fatty acids in form of lipids, and the development of engineered adipose tissues would benefit from improved techniques for analysis of lipid droplet composition, distributions, and dynamics based as a function of fatty acid saturation. Conventional microscopic techniques, such as fluorescence microscopy, provides excellent selectivity of lipid-based structures inside adipose tissue cellular structures based on staining with compound dyes. However, fluorescence staining limits multiplex imaging, and requires time consuming steps in preparing the samples for imaging. Therefore, developing a label-free, high resolution imaging platform with sensitivity to lipid composition could enable analysis of structural and compositional differentiation of lipid droplets within adipocytes during differentiation could give valuable insights into the importance of lipid droplets role in metabolism. As an important step towards achieving this goal, a femtosecond based CARS microscopy imaging platform has been developed to perform in vitro, label-free, imaging of fatty acid composition within engineered adipose tissues. / Bioengineering
129

Application of the finite element method in high-side gondola rail car design

Schmidt, Gerald 20 November 2012 (has links)
Finite element models of four design configurations of a proposed composite aluminum-steel high-side coal gondola rail car were developed. The designs were analyzed for compliance with the loadings set forth by the Association of American Railroads. Each of the first three designs were analyzed to check design concepts and alternatives with the fourth design being the final design planned for a prototype car. The results of the finite element analyses indicate that the final design is acceptable. However, two areas exist where results taken literally indicate a negative margin of safety. These areas are in the end sill to draftsill connection and in the draftsill casting. These conditions appear to be inconsequential since in the end sill case, the high stress is apparently caused by modeling constraints and the draftsill casting is a traditional design and is in common use on current cars and therefore should not cause any service problems. Step-by-step application of the finite element method to this design process is presented along with discussion of some significant element formulation assumptions and modeling methods. / Master of Science
130

Display of finite element beam stresses

Sparrer, John David 13 October 2010 (has links)
In this thesis, a computer program for graphically displaying finite element beam stresses is discussed. Beam elements are represented as thick lines with colored stress contours along the length. Stress gradients through the beam thickness are not displayed. Many program options are available to aid in creating a clear view of stress distributions in complex models. The front, right, top, and isometric views are preprogrammed views, or a rotated view of the model can be specified. Also, specific portions of the model can be magnified. A region may be defined for showing cut sections of the model. Contour options are available to help enhance stress representation. Node locations may be marked, and beam line widths modified. Finally, any view that has been developed can be saved in a file to be redisplayed at a later time. The program also has the capability of displaying resultant beam forces and moments. Beam stress displays for two train car models are used to demonstrate the usefulness of the program as both a presentation and modeling diagnostic tool. Stress gradients and high-stress regions are easily seen. With these displays some model discrepancies were uncovered and some highly stressed locations were observed that had not been discovered in the prior research. / Master of Science

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