• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 901
  • 384
  • 147
  • 76
  • 47
  • 38
  • 24
  • 17
  • 14
  • 12
  • 12
  • 8
  • 8
  • 8
  • 8
  • Tagged with
  • 1984
  • 641
  • 491
  • 268
  • 204
  • 173
  • 166
  • 157
  • 152
  • 140
  • 136
  • 135
  • 132
  • 129
  • 129
  • 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

Topology optimisation in crashworthiness design via hybrid cellular automata for thin walled structures

Hunkeler, Stephan January 2014 (has links)
Crashworthiness design is one of the most critical areas of automotive design. It is really demanding for the structure and can therefore have a large influence on the final design. It is also difficult to model accurately and costly to simulate which has an important impact on the design process. Most car companies have now stopped addressing crashworthiness design with trial and error approaches, in favour of more advanced automated structural optimisation methods. While most relevant applications so far use size or shape optimisation, the ultimate way to achieve significant mass reduction is to use topology optimisation. However, topology optimisation methods for crashworthiness design are still a work in progress. Due to the high non-linearity of crash simulations, well-established classic topology optimisation methods cannot be applied directly to crashworthiness design. Alternative methods have been and keep being developed such as the Equivalent Static Loads method, the Ground Structure Approach or the Hybrid Cellular Automata (HCA). This thesis introduces an adapted version of Hybrid Cellular Automata using thin-walled ground structures. It combines the advantages of computing a real crash simulation while producing as an output a thin walled based topology needing minimal post-processing effort to be translated into a realistic design. In this method, the topology optimisation domain is filled up with a ground structure of thin walls which constitutes the elementary cells of the HCA method. These macro-elements replace the solid mesh elements used in the classic HCA approach. The details and implementation of the method are presented and discussed. Different application examples are detailed, including defining reinforcement patterns within extruded beams. Enriched space fillings patterns are studied and industrial application examples are presented. Eventually, recommendations for further studies and applications of the method are given.
32

Alignment of ERM with performance management : the case study of automotive industry

Matin, Seyedeh Mandana January 2017 (has links)
This research explores the evolution of risk management practices, from traditional to enterprise risk management (ERM), in Iran's automotive industry. It also investigates the alignment of ERM and performance management, and their mutual impact. Academic and industry studies reveal that throughout recent decades there has been an increasing interest into ERM development and its alignment with performance management. However, despite the increase in ERM adoption over recent years, ERM is still in the early stages of implementation and requires further research and development. Moreover, a literature review revealed that the literature in respect of the alignment of ERM with performance management is limited and those existing are mostly of a visionary nature and lack practical implementation. Therefore, the gap identified through the literature review led to the development of a theoretical framework within this research, exploring the main organisational elements significant to the effective alignment of ERM and performance management and its implementation, which will provide practitioners and academics with practical guideline regarding such alignment. This research was completed through two empirical stages within the context of automotive industry. The primary data were collected and analysed through a mixed methods approach: 30 semi-structured interviewees were conducted with senior managers within the automotive industry (Qualitative). In the second stage, automotive industry professionals' responses were gathered from 101 survey questionnaires (Quantitative). The theoretical and empirical findings of this research confirm that in the recent decades, risk management has been evolving and transforming from its traditional approach to a strategic foundation, leading organisations towards competitive advantage and value creation. This research also indicates that aligning ERM with organisational performance management is critical in establishing a sustainable ERM and enhancing business performance over time. Based on the empirical findings of this research supported by theoretical findings, a lack of support from senior managers for effective ERM implementation and its alignment with performance management is considered as one of the significant challenges of sustainable ERM. In addition, a lack of ERM infrastructure and shareholders' poor understanding of ERM remains as challenging factors in aligning ERM with performance management. To the Researcher's best of knowledge, there is very limited literature into alignment of ERM and performance management in automotive industry. Therefore, this research's main contribution to the body of knowledge is the development of an effective framework for automotive industry, aligning ERM with organisational performance management, along with guidance for its implementation in practice. The key limitation associated with this research is that, due to complexity of ERM and its incorporation with other management functions and various organisational elements in the developed framework (Chapter 7, Section 7-1), it might be difficult somewhat to manage at the beginning of the framework adoption. It should be emphasised that the framework has been developed for those organisations that have a good understanding of ERM principles. So, this limitation might apply to those with inadequate knowledge of ERM. In addition, the developed aligning framework addresses the challenges and concerns of automotive industry organisations in aligning ERM with performance management. Applying this research in other sectors and industries provides the opportunity to investigate the potential changes and/or collaboration of certain elements of the framework based on the business area that the organisation operates in. The Researcher recommends further investigation into intangible organisational factors, such as how critical ERM culture could be effective in alignment of ERM with performance management. Moreover, the Researcher recommends that as ERM is growing quickly, future studies should continue to reveal and correlate new factors into the current framework. It is further recommended that future researchers could attempt to measure the benefits as well as the shortcomings associated with implementation of the aligning framework. This enables management with in organisations to improve the framework's advantage and to attempt to overcome its limitations.
33

Impact modeling of spot-welded columns fabricated with advanced high strength steels

Portillo Martínez, Oscar January 2005 (has links)
No description available.
34

Comparative investigation of large eddy simulation and RANS approaches for external automotive flows

Brondolo, Luca 07 1900 (has links)
This thesis investigates the accuracy and scalability of RANS and LES approaches applied to external automotive aerodynamics. Due to the availability of considerable experimental and computational data available on the Ahmed body, this reference model was chosen for this study. The relative simple geometry of the Ahmed body model is able reproduce the common flow features of a hatch back style vehicle. The 25° slant angle configuration was used as it is a major challenge in terms of flow prediction. The RANS model used included the Standard K-ε, RNG K-ε, Realizable k-ε and K-ω SST. The LES simulations were run with the Smagorinsky-Lilly SGS model. Three grids with different level of refinement were generated. A viscous hybrid mesh approach was used for all the simulations. This type of mesh is commonly used by automotive manufactures and motorsport organizations. The commercial package Fluent 12 was used as a solver. The K-ω SST and LES models showed good agreement with the experimental data. LES in particular was the only model to predict flow re-attachment over the slant angle as seen on the experimental and computational data available in literature. The richness of the unsteady data available from the LES simulations and correct interpretation of flow topology balance in part the major computational requirements compared to the RANS models. Taking into account the hardware resources available to automotive manufactures, the LES is suitable to be part of the design process.
35

The Haptic Drive : Haptic feedback for car interfaces

Feuš, Miha January 2013 (has links)
With the use of touch-screen enabled interfaces, came a new era for in-car interactions. Sadly, no technology comes without drawbacks, in this case the demand of visual attention, which is desperately needed to operate the vehicle in a safe manner. The main motivation for this project is finding a way to bring the sense of touch back to interfaces while retaining the flexibility that touch-screens have introduced. The collaborating partner for this project was Icon Incar, who also supported it in many ways. The research phase of this project has been carried out at the company HQ in Berlin. This included feedback sessions at the company, reading research papers on haptics and automotive interfaces, talking to experts in the field of haptics and the facilitation of a workshop. The research helped to confirm the initial problem statement and helped to form ideas in the ideation stage, of which there were many. Those ideas were a mixture of technologies and sensing abilities that went far beyond the initial problem statement in order keep a brother scope. There were many feedback session, with different people, which were necessary to weed out the bad ideas and keep the viable ones for testing. While building and testing the first prototypes, there was simultaneously a quest going on to find a solution for fully actuated and shape shifting displays, something that has not been done before. While coming up with dozens of possible technical solutions, the fact was overlooked that none of them would provide a good experience (except some far fetched futuristic granular systems). As it turns out, actuating the display itself would not cause any problems, but manipulating the actuation would, because it would not give the best experience. Manipulating actuated button would work and feel just fine, but sliders and knobs - whenever the finger has to move over a surface - would feel unnatural. After more analysis, I found that there is not one technology yet, that could stimulate all the different properties a human being can feel with the sense of touch. Therefor, there have to be many technologies working together to provide the best possible experience. More than a dozen haptic prototypes have been built and tested to help the users perform various tasks blindly. Those ranged from controlling the climate, scrolling throughout lists, identifying functions and getting feedback for selected options. Many of the ideas did not work out as expected and were discontinued after the haptic testing, which was a vital part of the process. The working ideas were then combined into a larger concept. To simplify the interface even more, a general list of features was thoroughly studied so that functions could be simplified, combined or discarded. Drivers and car dealers have been interviewed to understand what the most commonly used functions are. The analysis of existing interfaces has shown that there is currently only one function and type of information provided at any time. This means that the driver can not see directions while changing the music, for example. The concept layout will, therefore, provide information about all the basic functions (climate control, navigation, music and phone) where one function shows all information and others only the basics. To avoid visual clutter and ensure quick recognition, graphic elements have been distilled to their essential forms while still retaining a sense of visual pleasure. To identify, differentiate between and set climate control, the knob for heating would change its temperature, the ventilation knob blow air at the set speed and the air flow direction knob would tilt in the set direction. While the volume knob would react to the beat of the music. With the help of microfluidics, active buttons would pop out of the screen and can be identified by their shapes. When activating those shape shifting buttons, the driver would feel feedback, similar to the one of real buttons, provided by an actuator at the back of the display. The combination of all listed solutions would provide simpler interactions and help the drivers to keep their focus on the road. This would in turn make driving a better and safer experience.
36

A stochastic approach to motorcycle dynamics

January 2009 (has links)
A study on the applicability of the Monte Carlo method in the analysis of the dynamical behavior of motorcycles subject to road excitation is presented. To this end, a time-domain numerical simulation of the response of a motorcycle modeled as a linear four-degree-of-freedom (4-DOF) system, and traveling at constant speed is carried out. To validate the accuracy of the solutions obtained, the linear 4-DOF model is also analyzed using the frequency domain approach. Although the Monte Carlo simulation can be computationally costly, it provides an excellent scheme of analyzing, as well, non-linear systems, in which case the frequency domain approach cannot be applied. In this context the applicability of auto-regressive (AR) and autoregressive-moving-average (ARMA) filters for efficient implementation of the Monte Carlo simulation is pointed out. Furthermore, a practical engineering approach is presented for improved road roughness power spectral density (PSD) representation, and statistical parameters of the excitation signals synthesized.
37

Automotive third party logistics in China

Ketels, Helge January 2011 (has links)
This Master’s thesis concentrates on the investigation of the automotive third party logistics (3PL) industry in China. Therefore the overall aim of this thesis is the investigation of the Chinese 3PL environment with the focus on automotive industry. In order to clarify this aim, following four research objectives are set: 1)      Identify barriers and conditions of the 3PL market, taking automotive market as an example market for 3PL services. 2)      Identify market specific logistics services and compare different logistics services providers in this environment. 3)      Assess the Chinese industrial structures and their impact on foreign enterprises and create an actual picture of the automotive industry. 4)      Detect industrial structures’ influences on logistics services competition. Such a research is important as existing research focused on these objectives is extremely rare or not present. The research objectives are solved by a multi-method approach. In wide areas this thesis is a descriptive study. Thus barriers and conditions of the 3PL market, taking automotive market as an example market for 3PL services, are identified in an extensive literature review and combined with findings from interviews. These interviews are performed in a case company which is active in the Chinese automotive 3PL market. Many important characteristics and circumstances which can mainly be seen as barriers for logistics business are identified in the areas of Infrastructure and equipment, Supply and demand of logistics services, Importance of relationships, Legal issues and Staff requirements. Market specific logistics services are also identified in a literature review. In a next step these services are used to compare seven relevant 3PL providers in the industry by doing a questionnaire survey. The research shows that services mentioned in literature present in the industry. No significant differences between different competitors can be found. Thus none of these companies shows a competitive advantage due to their service portfolios. Industrial structures for both industries automotive manufacturing and automotive 3PL are assessed by combining findings from literature and from empirical internet research. Thus industrial structures in China are ruins of earlier years in China’s history. State-owned enterprises play an important role in China’s automotive manufacturing industry. These companies are involved in the overwhelming share of the passenger car production. An interesting finding is that most passenger cars arise from joint ventures between these Chinese car groups and foreign car manufacturers. The Chinese car groups and the joint ventures create a network like structure in the industry. 3PL providers appear differently. Major companies identified are wholly-owned foreign companies, joint-ventures between Chinese car groups and foreign logistics providers or subsidiaries of car groups. Affiliations between logistics joint ventures and Chinese car groups indicate that competition might not be unrestrictedly present in the market.
38

none

CHAO, JUI-CHUN 16 July 2003 (has links)
Automotive industry in China is probably one of the most potential emerging markets all over the world along with the trend of the ¡§China Flu¡¨. More than that, the well-know market demand over the 2002 is prosperously exceeded over the average estimation. The total vehicle production quantity is 3.25 million pieces versus almost the equivalent sold out quantity, the attractive numbers pushing China Auto market upward the rank of the 4th largest regional market, and become the only market cranking upward with the growth rate at 30%, while most of the other markets are suffering severely worldwide recession. China automakers and automotive electronic components makers become world-class auto manufacturers' strategic partners. Therefore, the research deals with the extent to which multinational tier 1 and tier 2 enterprises and China local makers clustering segment as the new China auto industrial landscape rely on Taiwanese automotive components suppliers with the most suitable entry mode as well as the competing advantage throughout the newly emerging supply chain in China OE segments, how Taiwanese suppliers find a way to be upgraded as a global player via the collaboration synergy of China market. The methodology for the research is utilized the case study approach and the interview with the leading edge industrial players for both China auto makers and multinational Tier 1 giants. After literature review and case study analysis, we highlight the most suitable entry strategy as ¡§niche strategy¡¨ and ¡§collaboration alliance¡¨ with the deliberation in terms of the Taiwanese makers SWOT analysis. For Taiwanese makers, they have some advantages, such as 1). leverage of resources; 2).integrator role played between Western and China connection; 3).booster of Taiwan¡¦s globalization; 4).enlarging the market place from regional to international level; 5).smooth over the political conflict for enhanced collaboration to reach the win-win synergic solution. Tenth Five-Year Plan published in June 2001 as the highest regulatory that is the major forces driving China automotive industry forward, in which the motor vehicle production was expected to reach some 3.2 million in 2005, including 1.1 million cars. Automotive industrial added value will reach RMB 130 billion, accounting for 1% of GDP. By 2005, the 2-3 large automotive enterprise groups ( First Auto Works, Shanghai Auto Industry Corp.,and Dongfeng Motor Corp.) with certain international competitiveness will be formed and fully supported by the state, making use of all kinds of preferential policies, whose products share over 70% of domestic market with some exports. The 5-10 large enterprise groups for automotive parts and components with initial international competitiveness will be built up. The top three enterprise groups for key automotive parts and components will have market share 70% of domestic market. Technical renovation projects in line with the Tenth Five-Year Plan of automotive industry and beneficial to the restructuring of automotive industry will be given priority to indirect financing and a modern development, production and marketing system will be encouraged to establish. Consequently, the State encourages the autonomous development of leading parts and components enterprises to enhance their competitiveness. Different ownerships are encouraged to participate in the development of auto part and component industry with the policy of the strategic alliance in order to innovate a newly modern value chain with the world wide expertise ¡¨clustering effects¡¨. Leading enterprises emerging as ¡§super suppliers¡¨ as innovation term of ¡§tier 0.5¡¨ for Automotive parts and components supported by 3 OE Giants FAW, SAIC and DMC. The tier 0.5 super suppliers such as Fawer under FAW, STEC under SAIC and DFT under DMC will be guided to develop the specialization of the system provider and module integrator for effectiveness of economies of scale. The research has two implications ---the interface strategy of Taiwan automakers is the ¡§niche strategy¡¨ and ¡§collaboration alliance¡¨. As far as the penetration and competing strategy development of Chinese market is concerned, the ¡§niche strategy strategic role played by Taiwanese have an absolute effect on the second level OE car makers to avoid competing with larger firms by targeting small markets of little or no interesting to the larger firms. Collaboration alliance connecting both of Mainland China domestic makers to the western countries facilitated by horizontal collaboration for market development and technology enhancement, because Taiwan belongs to the same cultural region as Mainland China. Besides. The research also suggests the competing strategies; such as reinforce the self-technology capability incubator, leverage of Taiwan IT and IC industry competing advantage to back up the automotive electronic upgrade, emphasize the role played as an multinational enterprise, strengthen the global wise alliance as well as the worldwide marketing channel connection. The active participation of Taiwanese suppliers is also an essential factor that raises the status as interface strategy. Taiwan makes use of core competences to play the role of ¡§critical unique link¡¨ without being left out from the emerging value chain of the highly potential China market.
39

Growth Strategy for Taiwanese Suppliers in China OE Automotive Market - L Company Perspective.

Hsieh, Cheng-wen 11 September 2008 (has links)
China has become the most significant market in the world, since both the high demanding quantity and high potential in growth. China was ranked world wide number three for car sales and number two for car production volume in year 2007. In the meanwhile, according to the forecasting, China auto market will keeping in a growth rate higher than two digits in the coming five years. In contrast to the other major auto markets, USA, Europe and Japan, those markets are all keeping in low even minus sales growth cause from impacted by both the high gasoline price and economy depression. The purpose of this thesis is trying to fig out the competitive strategy and growth model for the Taiwan based automotive suppliers who already became China auto¡¦s supplier. Those suppliers have a very tough situation in China, due to them not only must face the giant global tier one but also the aggressively local based suppliers in China Auto market. The thesis will take the aspect of Taiwan based automotive suppliers, and probe into how those suppliers seeking the niche market and growth opportunity in such a severe market place. The specific objectives are: 1. Overview the Chinese automotive market and also predict the trend of such market. 2. Find the growth and also the competitive strategy for those suppliers. Through study the related thesis and publications, interview the insiders, analysis the row data/ industry survey reports and also combine with author¡¦s field experience in automotive, this thesis will come out below results: 1. General model for growth strategy. 2. The specific growth model for Taiwan based auto suppliers in China. 3. The competitive strategy for Taiwan based auto suppliers in China. 4. Suggestions for Chinese automotive suppliers.
40

Design and experimental characterization of electrostatically assisted automotive fuel injectors /

Anderson, Eric Karl, January 2009 (has links)
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2009. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3631. Adviser: Dimitrios C. Kyritsis. Includes bibliographical references (leaves 144-149) Available on microfilm from Pro Quest Information and Learning.

Page generated in 0.0755 seconds