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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.
171

Lithium availability and future production outlooks

Vikström, Hanna, Davidsson, Simon, Höök, Mikael January 2013 (has links)
Lithium is a highly interesting metal, in part due to the increasing interest in lithium-ion batteries. Several recent studies have used different methods to estimate whether the lithium production can meet an increasing demand, especially from the transport sector, where lithium-ion batteries are the most likely technology for electric cars. The reserve and resource estimates of lithium vary greatly between different studies and the question whether the annual production rates of lithium can meet a growing demand is seldom adequately explained. This study presents a review and compilation of recent estimates of quantities of lithium available for exploitation and discusses the uncertainty and differences between these estimates. Also, mathematical curve fitting models are used to estimate possible future annual production rates. This estimation of possible production rates are compared to a potential increased demand of lithium if the International Energy Agency’s Blue Map Scenarios are fulfilled regarding electrification of the car fleet. We find that the availability of lithium could in fact be a problem for fulfilling this scenario if lithium-ion batteries are to be used. This indicates that other battery technologies might have to be implemented for enabling an electrification of road transports. / Stand
172

Being Green: One and Done

Wernet, Katherine 01 January 2011 (has links)
This study aims to understand the extent to which Prius owners are susceptible to single action bias, a phenomenon that occurs when one executes an initial, single action to solve a particular problem and then ceases to take further action. Here, participants were of two groups – Prius owners and non-Prius owners. It was hypothesized that Prius owners would, in fact, be less likely to perform smaller, easier green tasks (such as recycling) than those who did not own the hybrid – simply because they believed they have already done their part for the environment. Results failed to allow a rejection of null hypothesis. Further explored in the non-Prius group was recycling as the initial, single action, and a significant positive spillover effect was seen. Concern for the environment, regardless of car ownership, was a significant factor in green behavior. The Prius as a public statement of one‟s attitude is discussed.
173

The Impact of the Transfer of Intangible Assets on the Valuation Effects of High-Tech Cross-Border Mergers and Acquisitions

Sinclair, Andrew John 30 August 2009 (has links)
The technology industry is characterized by a greater than usual reliance on intangible assets. During the tech bubble many firms were valued entirely on intangible assets and growth prospects. In the aftermath of the bubble, intangible assets still play an important role as the innovative performance of a firm’s human capital and the value of its patents creates much of the value of high-tech firms. The problem of transferring human capital and knowledge may be further exacerbated when the firms belong to separate national cultures. Investor perception of acquisition announcements may be more favourable if the target workforce is much smaller relative to the bidder, and thus easier to integrate. Also, perceptions may be favourable when the target has a high ratio of intangible assets to total assets, as this may be a proxy for the relative value of the extractible intangible assets. This study uses a sample of 61 acquisition announcements between 1991 and 2004, where both acquirer and target are high-tech firms and accounting and trading data is available from three years prior to three years after the acquisition announcement. There is weak evidence to support the employee ratio hypothesis for bidder returns, and no evidence to support the intangible assets to total assets hypothesis for either bidder or target returns. Additionally, it is found that average bidder abnormal returns during the announcement period (as measured from one day prior to the announcement acquisitions to one day afterwards) are negative but not significantly different from zero, and that average target abnormal returns are positive and significant. Average wealth gains to bidders are negative and to targets are positive over the window from five days prior to the acquisition announcement to five days afterwards. Furthermore, combined wealth gains are negative, indicating the synergistic gains from high-tech cross-border acquisitions are offset by high premiums paid by the bidders for the targets. Relatedness, a lack of tender offers, and non-US acquirer status are demonstrated to be related to negative returns to bidders, whereas tender offers, US-acquirer status, and termination provisions are shown to be related to increased returns to target shareholders. In the long-run, it is found that acquirers experience superior operating cash flow returns when compared to their industry peers, however, the acquirer experiences diminished performance when compared to the combined performance of the pre-acquisition acquirer and target firms.
174

Automated Analysis of Automotive Read-Out Data for Better Decision Making

Saleem, Muhammad January 2011 (has links)
The modern automobile is a complex electromechanical system controlled by control systems which consist of several interdependent electronic control units (ECUs). Analysis of the data generated by these modules is very important in order to observe the interesting patterns among data. At Volvo Cars Corporation today, diagnostic read-out data is retrieved from client machines installed at workshops in different countries around the world. The problem with this data is that it does not show a clear picture as what is causing what i.e. tracking the problem. Diagnostic engineers at Volvo Cars Corporation perform routine based statistical analysis of diagnostic read-out data manually, which is time consuming and tedious work. Moreover, this analysis is restricted to basic level mainly statistical analysis of diagnostic readout data. We present an approach based on statistical analysis and cluster analysis. Our approach focused on analysing the data from a pure statistical stand-point to isolate the problem in diagnostic read-out data, thereby helping to visualize and analyse the nature of the problem at hand. Different general statistical formulae were applied to get meaningful information from large amount of DRO data. Cluster analysis was carried out to get clusters consisting of similar trouble codes. Different methods and techniques were considered for the purpose of cluster analysis. Hierarchical and non-hierarchical clusters were extracted by applying appropriate algorithms. The results obtained from the thesis work show that the diagnostic read-out data consist of independent and interdependent fault codes. Groups were generated which consist of similar trouble codes. Furthermore, corresponding factors from freeze frame data which shows significant variation for these groups were also extracted. These faults, groups of faults and factors were later interpreted and validated by diagnostic engineers.
175

The Impact of the Transfer of Intangible Assets on the Valuation Effects of High-Tech Cross-Border Mergers and Acquisitions

Sinclair, Andrew John 30 August 2009 (has links)
The technology industry is characterized by a greater than usual reliance on intangible assets. During the tech bubble many firms were valued entirely on intangible assets and growth prospects. In the aftermath of the bubble, intangible assets still play an important role as the innovative performance of a firm’s human capital and the value of its patents creates much of the value of high-tech firms. The problem of transferring human capital and knowledge may be further exacerbated when the firms belong to separate national cultures. Investor perception of acquisition announcements may be more favourable if the target workforce is much smaller relative to the bidder, and thus easier to integrate. Also, perceptions may be favourable when the target has a high ratio of intangible assets to total assets, as this may be a proxy for the relative value of the extractible intangible assets. This study uses a sample of 61 acquisition announcements between 1991 and 2004, where both acquirer and target are high-tech firms and accounting and trading data is available from three years prior to three years after the acquisition announcement. There is weak evidence to support the employee ratio hypothesis for bidder returns, and no evidence to support the intangible assets to total assets hypothesis for either bidder or target returns. Additionally, it is found that average bidder abnormal returns during the announcement period (as measured from one day prior to the announcement acquisitions to one day afterwards) are negative but not significantly different from zero, and that average target abnormal returns are positive and significant. Average wealth gains to bidders are negative and to targets are positive over the window from five days prior to the acquisition announcement to five days afterwards. Furthermore, combined wealth gains are negative, indicating the synergistic gains from high-tech cross-border acquisitions are offset by high premiums paid by the bidders for the targets. Relatedness, a lack of tender offers, and non-US acquirer status are demonstrated to be related to negative returns to bidders, whereas tender offers, US-acquirer status, and termination provisions are shown to be related to increased returns to target shareholders. In the long-run, it is found that acquirers experience superior operating cash flow returns when compared to their industry peers, however, the acquirer experiences diminished performance when compared to the combined performance of the pre-acquisition acquirer and target firms.
176

IT i bilen : En fallstudie av ubikvitär datorisering

Gyllhamn, Noel, Jonsson, Klas January 2012 (has links)
This paper aims to study the possibilities and challenges the car industry has to face with applying information technology in cars. The goal is to describe and analyse all the existing technology in the cars out on the market today as well as future possible technologies in cars. By interviewing people who has been working or are working with information technology in cars, we aim to clarify the obstacles and opportunities in the process of implementing informatics in cars. With this knowledge we want to learn more about Ubiquitous computing and how humans interact with Ubiquitous computers today and will be interacting in the future. Technology has a rapid development pace and we find it interesting to examine how the car industry can keep up with the rapid development pace of technology.
177

Untersuchungen zum Einsatz berührungsloser In-situ-Messmethoden für die Analyse metallurgischer Gase

Sandlöbes, Stefanie January 2009 (has links)
Zugl.: Aachen, Techn. Hochsch., Diss., 2009
178

Framtidens elbilar utmanar nutidens elnät : Påverkan av ett ökat antal elbilar på ett halländskt elnät / The electric cars of the future challenge today's power grid

Deutschmann, Oliver, Johansson, Thomas January 2015 (has links)
The challenges facing low voltage grids are rising as an increasing number of domestic houses transition from fossil fueled heating to electricity based heating. Several environmental goals and visions have the same transition from fossil based power to electricity based power in mind for the transportation sector. One of the most important tools for this transformation is widely regarded to be the electric vehicle. With the demands of the electric vehicle pressuring the power grid, several questions arise regarding the growth of the electric vehicle market and what repercussions it may have on the grid. This paper focuses on a typical low voltage grid in southern Sweden and what effects a growing electric vehicle market may have on it. Through computer-assisted simulations based on several future scenarios regarding the EV market, this paper finds that few modifications and reinforcements are needed on this particular grid within the next 10 to 15 years. After this timeframe the voltage drop becomes a serious concern and should be addressed. / Utmaningarna som lågspänningsnät står inför växer i takt med att fler bostäder övergår från fossilbaserad till elbaserad värme. Flera miljösatsningar och visioner ämnar pådriva samma förändring inom transportsektorn och eldrivna fordon anses som ett av de viktigaste verktygen för att genomföra detta. Med ytterligare potentiella påfrestningar på lågspänningsnäten från de elektriska fordonens behov ställs frågan hur utbredd den elektriska fordonsmarknaden kommer att bli och vilken påverkan den kommer ha på elnäten. I detta arbete belyses ett typiskt lågspänningsnät i södra Sverige och vilka effekter elfordonens utbredning kan tänkas ha på den. Genom datorstödda simuleringar enligt flera olika prognosscenarion finner arbetet att relativt få förändringar och förstärkningar behöver göras på det analyserade nätområdet inom ett tidsspann på ca 10 till 15 år. Efter detta tidsspann orsaker lasterna ett högt spänningsfall i det aktuella nätet som bör åtgärdas.
179

Replacement policies for multiple component systems

Suraweera, Alankarage Wedeha January 1979 (has links)
published_or_final_version / Industrial Engineering / Master / Master of Philosophy
180

Influence of wagon structure on the vertical response of freight.

Loubser, Richard Clive. January 2002 (has links)
Historically, wagons have been designed according to the American Association of Railroads specifications. These require that wagons be designed to withstand a static load between the couplers of 350 tons. This implies that the structure has a certain stiffness. In order to improve load to tare ratio, there has been talk of reducing the end load specifications. This implies that the stiffness of the wagon will reduce. Using more flexible wagons implies that the freight will probably be exposed to a harsher dynamic environment. There is a trade off between the cost of packaging and the cost of protection devices installed in the vehicle. If handling damage can be prevented then an understanding of the dynamic environment will assist in reducing the packaging requirement. This research looked at the dynamic characteristics of an existing design of wagon using modal analysis. The results from the modal analysis were extended to be inputs to the time domain freight model. Various analytical models of the freight were developed depending on the configuration and dynamic properties. Special consideration was given to a cylinder with its axis transverse to the wagon. The modal model was modified to accommodate the change in mass imposed by the freight. The various sources of dynamic excitation were explored, namely inputs from the coupler and from the bogie. Data from shunting yard simulations were used to generate spectra as input to the wagon model. The objective was to use modal techniques to be able to take individual components, form them into a complete model and make informed decisions about the suitability of a certain configuration for traffic. / Thesis (Ph.D.)-University of Natal, Durban, 2002.

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