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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.
101

Fiber-reinforced composite materials for coal transportation railcar bed

Zhou, Junlin 04 June 1999 (has links)
The material properties of the candidate fiber-reinforced composite materials and different fabrication methods for fiber composites were discussed. The improvement of the hand lay-up process for polyurethane impregnated Kevlar was investigated. Testing samples for lab and prototype tests were fabricated by hand lay-up process. The study showed that fiber composites fabricated by the hand lay-up process can achieve good properties, and advanced fabrication methods could be applied In industrial manufacturing processes to improve the fiber composite properties. A nonlinear static analysis was discussed. The ANSYS finite element analysis computer program was used to build stress analysis models, simulate the loading conditions, and perform the nonlinear static analysis. The tensile strength proof test was designed and done by using a microcomputer controlled Instron 4505. It showed that the different types of fiber composites can meet the strength requirements for the application. Polyurethane impregnated Kevlar showed the best strength properties among the different types of fiber composites, which were fabricated and tested. The wear and abrasion properties of the different types of fiber composites were discussed and relevant tests were introduced. An ultraviolet light exposure test and the Oregon Department of Transportation road-cover test were conducted. Moisture and acid resistance and cost analysis were also discussed. Based on the results of the study, a prediction of the optimal fiber-reinforced composite materials was made. Also, various conclusions and recommendations for future research work were made. / Graduation date: 2000
102

Coherent anti-Stokes Raman scattering (CARS) optimized by exploiting optical interference

Wang, Xi 2011 May 1900 (has links)
The purpose of this work is to study the interference between the coherent nonresonant four-wave-mixing (FWM) background and the Raman-resonant signal in the coherent anti-Stokes Raman spectroscopy (CARS). The nonresonant background is usually considered as a detriment to CARS. We prove that the background can be exploited in a controllable way, through the heterodyne detection due to the interference, to amplify the signal and optimize the spectral shape of the detected Raman signal, and hence enhance the measurement sensitivity. Our work is based on an optimized CARS technique which combines instantaneous coherent excitation of multiple characteristic molecular vibrations with subsequent probing of these vibrations by an optimally shaped, time-delayed, narrowband laser pulse. This pulse configuration mitigates the nonresonant background while maximizing the resonant signal, and allows rapid and highly specific detection even in the presence of multiple scattering. We investigate the possibility of applying this CARS technique to non-invasive monitoring of blood glucose levels. Under certain conditions we find that the measured signal is linearly proportional to the glucose concentration due to optical interference with the residual background light instead of a quadratic dependence, which allows reliable detection of spectral signatures down to medically-relevant glucose levels. With the goal of making the fullest use of the background, we study the interference between an external local oscillator (nonresonant FWM field) and the CARS signal field by controlling their relative phase and amplitude. Our experiment shows that this control allows direct observation of the real and imaginary components of the third-order nonlinear susceptibility (χ(3)) of the Raman sample. In addition, this method can be used to amplify the signal significantly. Furthermore, we develop an approach by femtosecond laser pulse shaping to precisely control the interference between the Raman-resonant signal and its intrinsic nonresonant background generated within the same sample volume. This technique is similar to the heterodyne detection with the coherent background playing the role of the local oscillator field. By making fine adjustments to the probe field shape, we vary the relative phase between the resonant signal and the nonresonant background, and observe the varying spectral interference pattern. These controlled variations of the measured pattern reveal the phase information within the Raman spectrum, akin to holographic detection revealing the phase structure of a source.
103

Kommunikation i förändringsarbete : vilken roll spelar kommunikation för chef och ledare i en LEAN förändring / Communication and Development : what is the role of communication for a manager or leader in a LEAN developing process

Henningsson, Annika January 2011 (has links)
Examensarbetet inleddes med en förstudie där olika förbättringsområden inom organisationen identifierades. Kommunikation i praktiken kan liknas vid ett förstärkningsverktyg vilket påverkar de vanligaste faktorerna för ett lyckat förändringsarbete. Idag måste en ledare och chef vara kommunikativ och det fungerar inte längre med att peka med hela handen. Medarbetarna måste förstå sin chef och ledare och det måste finnas ett samspel mellan dem. För att chefer och ledare ska styra förändringsprocessen behövs kommunikation. Syfte med examensarbetet är att undersöka hur kommunikationsprocessen kan användas som styrmedel mot en social förändring. Målet med examensarbetet är att beskriva kommunikation för förändring på Volvo i Olofström och att identifiera förbättringsområden inom organisationen. Examensarbetets avsikt är att undersöka olika synvinklar ur kommunikation, ledarskap och förbättringar kring en förändringsprocess. De slutsatser som examensarbetet visar är att kommunikationsprocessen kan användas som styrmedel via information, kommunikation, möten och genom dialog. Kommunikation måste ske via chef och ledare och visuellt ledarskap. Kommunikation innebär att i dialog tala med varandra. Förbättringsarbetet som påbörjats bör fortsätta som del i organisationens förändringsarbete. Utifrån målbeskrivningen - Hur ledare kommunicerar för att uppnå förändringsmål visar resultat att chef/ledare ansvarar för kommunikations-processen när det gäller planering och genomförande av förändring i en arbetsgrupp. Organisationen kan då se chef/ledare som en förändringsledare. Förändringens resultat påverkas av hur kommunikationen genomförs. Förändring och utveckling sker via kommunikation och dialog i en samverkan. Utifrån målbeskrivningen – Hur kommunikation kan leda medarbetare mot förändring bör chef/ledare börja med att diskutera och kommunicera vad det innebär att gå från ett läge till ett annat läge i en LEAN förändring. Vidare visar resultat att chef/ledare behöver studera innebörden av resultat via analys och diskussion men framför allt vad det innebär att ge support och feedback. Strategisk kommunikation kan vara den del som saknas då kommunikation inte förstås. Utifrån målbeskrivningen – Hur Kommunikationen påverkas av LEAN ledarskap på Volvo Personvagnar AB Karosskomponenter (VCBC) noteras i resultatdelen att förändring och ledarskap inte kopplas ihop. Då kan chef/ledare inte utveckla kommunikationsprocessen mot en social förändring. / This thesis work began with a pre-study which intended to identify areas of improvement within the organization. Communication in practice is like a strengthening tool, which affects the most common factors for successful change management. Today, a manager must be communicative; just to point out the direction is not longer working. Employees must understand their manager and leader, and there must be an interaction between them. For managers to guide the change process communications is needed. The purpose of the thesis work is to investigate how the communication process can be used as instruments of social change. The goal of the project is to describe the communication of change at Volvo in Olofström and to identify areas for improvement within the organization. The intention is to examine different perspectives from communication, leadership and improvement on a process of change. The conclusions of the thesis work are that the communication process can be used as instruments through information, communication, meetings, and through dialogue. Communication goes through the manager and leader, and visual management. Communication means dialogue and to talk to each other.  The Improvement work which has started should be continued as part of the organization's change process. The central part of - How leaders communicate in order to achieve the goals of implementation. The responsibility of the communication process lies with the manager / leader for planning and implementing of the change in a workgroup. The organization can see the manager / leader as a leader of change. The results of implementation are affected by how communication is carried out. Change and development is done through communication and dialogue in an interaction. The central part of - How communication can lead people through implementation and development. It is up to the manager / leader to begin to discuss and communicate the meaning of transformation in a LEAN implementation. Furthermore the manager / leader need to study the implications of the results through analysis and discussion, but above all what it means to give support and feedback. Strategic communication can be the part that is missing when communication is not to be interpreted. The central part of - How communication is affected by LEAN leadership at Volvo Cars Body Components (VCBC). Found in the results is that change and leadership can’t connect to each other. In this case manager / leader do not develop the communication process of social change.
104

Visuella effekters påverkan på minne och popularitet : Reklamfilm för bilar

Kristoffersson, Mats, Sandberg, Glenn January 2012 (has links)
Car-commercials are something that many people come in contact with on a daily basis. This is a study on commercials for cars and is focusing on visual effects that are made in post-production. In this report we are trying to find out if and how visual effects in commercials for cars affect how the observer remembers them. The second subjects that we use in this report is popularity and we try to find out if and in that case how visual effects affect the commercials for cars popularity. We also investigated how frequently commercials for cars are showed on TV and how the visual effects are in them, it gives a better foundation to the other parts. The methods we applied were interviews, quantitative and qualitative content analysis of car commercials and also observation analysis of the 6 swedish TV-channels that shows commercials and have the most viewers, to get an idea how frequently these commercials are shown. The commercials that were applied in this paper was from late 2011 to early 2012. Interviews were made with people from the ages 16 to 76 years old with an equal distribution of sexes. We used 4 different commercials for cars in our interviews with 4 different degrees of the amount of visual effects. We analyzed 6 Swedish TV-channels that show commercials and that have the most viewers to get an idea about how frequently commercials for car are shown. The result of our research showed us that there was no connection between visual effects and popularity and that a larger amount of visual effects can increase the observers tendency to remember a commercial with 15 percentage. Most commercials from the studied period was without visual effects and 13,3% had a larger amount of visual effects
105

A study of Chinese consumers’ attitudes toward Volvo cars

Xiao, Shuyuan, He, Wei January 2011 (has links)
Zhejiang Geely holding Co. succeeded in purchasing Ford Motor Co’s Volvo unit, which was the hottest news in the world in 2010. Volvo needs the Chinese potential car market; Geely needs Volvo cars’ advanced technology. Such purchase arouses our interesting to conduct a research study on Chinese consumers’ attitude and intentions toward Volvo cars.   Our aim with this study was to identify the most important attributes of Volvo for Chinese consumers; to analyse how Chinese consumers were influenced by other people’s opinions and to explore how Chinese culture factors such as face concern and group conformity influence consumers’ attitudes  towards Volvo.   In order to find the result, we used online self-completion questionnaires and choose customers from a life insurance company in Shanghai as our sample group. From the survey result we found that Volvo is the second most favourable brand that Chinese consumers want to own in the near future. The top three car attributes for the Chinese consumers when they were going to choose a car were quality, safety and fuel economy. But they had less knowledge or beliefs that Volvo car has an advantage with those attributes. Besides that, we find that Chinese consumers’ behavioural intention of buying Volvo is influenced by family, friends, perceived behaviour control and group conformity, but there is no relationship between face concern and buying behaviour.
106

Sustainability & Consumer behavior towards Sustainability in Norway and Sweden

Khan, Aamir Qadeer, Kashif, Muhammad January 2010 (has links)
AimSustainability has become an important factor to consider while buying goods and services. People are being more conscious toward environmental impacts of products and services. This attitude has motivated many businesses to develop their production in contact with sustainability. The aim of this paper is to investigate different consumer behaviors toward sustainability in general and in relation to vehicles in Norway and Sweden.ApproachThe project has been embarked by dividing it into two tasks.1. Analyzing past, present and future development, growth and importance of sustainability concept. Describe the role of Government authorities in Norway and Sweden to promote sustainable consumption.2. Investigating important factors of consumer behaviors which influence their buying decision toward sustainable products in general and in relation to sustainable vehicles. Highlight the role of vehicle manufacturing companies to promote sustainable consumption.MethodA research has been conducted in order to explore consumer behavior toward sustainability in Norway and Sweden. Research is based on Document study and primary research which include questionnaire survey with consumers and interviews with vehicle dealers. In addition an expert inquiry is conducted to light up consumer intensions in Norway and Sweden toward sustainability.ResultsThe result of investigation has been revealed in shape of analyses and conclusion at the end. A comparison has been made between primary research and secondary research and findings are overlapping. Sustainable vehicles are being more popular among consumers in Norway and Sweden. Consumption trends are changing over time and environmental friendly attitudes are more developing among Swedish consumers as compared to Norwegian.
107

Detection of bacterial endospores by means of ultrafast coherent raman spectroscopy

Pestov, Dmitry Sergeyevich 10 October 2008 (has links)
This work is devoted to formulation and development of a laser spectroscopic technique for rapid detection of biohazards, such as Bacillus anthracis spores. Coherent anti-Stokes Raman scattering (CARS) is used as an underlying process for active retrieval of species-specific characteristics of an analyte. Vibrational modes of constituent molecules are Raman-excited by a pair of ultrashort, femtosecond laser pulses, and then probed through inelastic scattering of a third, time-delayed laser field. We first employ the already known time-resolved CARS technique. We apply it to the spectroscopy of easy-to-handle methanol-water mixtures, and then continue building our expertise on solutions of dipicolinic acid (DPA) and its salts, which happen to be marker molecules for bacterial spores. Various acquisition schemes are evaluated, and the preference is given to multi-channel frequency-resolved detection, when the whole CARS spectrum is recorded as a function of the probe pulse delay. We demonstrate a simple detection algorithm that manages to differentiate DPA solution from common interferents. We investigate experimentally the advantages and disadvantages of near-resonant probing of the excited molecular coherence, and finally observe the indicative backscattered CARS signal from DPA and NaDPA powders. The possibility of selective Raman excitation via pulse shaping of the preparation pulses is also demonstrated. The analysis of time-resolved CARS experiments on powders and B. subtilis spores, a harmless surrogate for B. anthracis, facilitates the formulation of a new approach, where we take full advantage of the multi-channel frequency-resolved acquisition and spectrally discriminate the Raman-resonant CARS signal from the background due to other instantaneous four-wave mixing (FWM) processes. Using narrowband probing, we decrease the magnitude of the nonresonant FWM, which is further suppressed by the timing of the laser pulses. The devised technique, referred to as hybrid CARS, leads to a single-shot detection of as few as 104 bacterial spores, bringing CARS spectroscopy to the forefront of potential candidates for real-time biohazard detection. It also gives promise to many other applications of CARS, hindered so far by the presence of the overwhelming nonresonant FWM background, mentioned above.
108

Utformning av webbportal för tjänstlediga medarbetare vid Volvo Cars Engine och utexaminerade elever från Volvogymnasiet

Becirovic, Edina, Sabic, Samira January 2006 (has links)
<p>This report describes the development of a web site for co-workers on leave of absence at Volvo Cars Engine AB and graduated students at Volvo Upper Secondary School in Skövde. The aim of the web site is to be a complement to existing communication channels in the promotion of the contact between the target group and the company. The work was divided into two parts; the first consisting of a preliminary study used to identify the information which the target group finds absent in their absence from their place of work/school, and the second part consisting of the development of a proposition of content layout and web site design. The finished proposition was presented along with a couple of alternatives for the technical implementation. The information department at Volvo Cars Engine AB in consultation with Volvo Cars IT will carry on the implementation, administration and further development of the proposed solutions.</p> / <p>Denna rapport beskriver utformningen av en webbportal för tjänstlediga medarbetare vid Volvo Cars Engine AB och utexaminerade elever vid Volvogymnasiet i Skövde. Syftet med portalen är att fungera som ett komplement till de befintliga kommunikationskanalerna i främjandet av kontakten mellan målgruppen och företaget. På sikt är målet att de tjänstlediga och utexaminerade eleverna ska välja att återkomma och satsa på olika karriärvägar inom Volvo.</p><p>Arbetet bestod av två delar. I den första delen genomfördes en förstudie för att identifiera information som målgruppen tycker sig sakna vid deras frånvaro från arbetsplatsen/gymnasiet. Förstudien realiserades med intervjuer med ägarna och nyckelpersoner på företaget, samt med telefonintervjuer med ett slumpmässigt urval från målgruppen. Resultatet av förstudien användes i arbetets andra del som gick ut på att skapa ett förslag på innehållslayout och design av webbportalen. Den andra delen av arbetet delades in i fyra faser. Under de fyra faserna togs det fram ägar- och målgruppsanalys, innehålls- och kravspecifikation, sidstruktur och layout samt grafisk design för webbportalen, med tonvikt på användarvänlighet enligt rekommendationer från Jakob Nielsen. Utformningen av layouten och designen hade p.g.a. företagets policy utgångspunkt i företagskulturen vad gäller design och layout på de externa webblösningarna.</p><p>Ett antal alternativ för den tekniska lösningen togs också fram. Dessa är open-source CMS på externt webbhotell, Volvo Cars portallösning på Volvo Cars webbserver, samt Fronter-portal på företaget DoubleClick AB´s server.</p><p>Det färdiga förslaget presenterades tillsammans med ett antal alternativ för den tekniska lösningen. Implementationen, förvaltningen och vidareutvecklingen av de föreslagna lösningarna drivs vidare av informationsavdelningen på Volvo Cars Engine AB i samråd med Volvo Cars IT</p>
109

Multimodal characterization of atherosclerotic cardiovascular disease with label-free non-linear optical imaging techniques

Mostaco-Guidolin, Leila Buttner January 1998 (has links)
Application of the nonlinear optical microscopy (NLOM) for investigation of biological samples has, to date, primarily focused upon the qualitative analysis of images. The general consensus is that the nonlinear optical (NLO) techniques provide enough bio- chemical information when compared to, for example, visible light microscopy. Herein, it is presented a detailed study where a set of tools for quantitative extraction of infor- mation from NLO images were developed and tested for the analysis of complex tissue assemblies. Two-photon excited autofluorescence (TPEF), second-harmonic generation (SHG), and coherent anti-Stokes Raman scattering (CARS) were used for the charac- terization of atherosclerotic plaques. Our NLO-based image analysis of animal arteries affected by atherosclerotic plaque accumulation revealed that images of the healthy regions of the artery can be readily distinguished by marked differences in morphology, due to a fluorescent signal generated from the presence of generally intact elastic layer. Regions affected by lesions were dominated by lipid-rich cells and collagen fibers; the elastic layer was disrupted and the presence of fluorescent particles were also detected. Next, the potential of using information extracted from NLO images lead us to the development of a new optical index for plaque burden (OIPB). Through the OIPB, it was possible to investigate and to classify the plaque severity regarding the already established and currently used definition during clinical analyses. Extrapolating to and anticipating future applications, several methods for extracting specific information from images acquired by each NLOM modality were developed and tested. Texture analysis, particle-specific features, fractal analysis and directionality of components within the images were successfully adapted and tailored to better extract relevant information from the NLO images. Even though the methods presented in this thesis were mostly tested in images from arterial plaques, there is strong evidence that all tools presented here are capable of tracking changes that occur in many medical conditions and applications.
110

Early stages of combustion development in internal combustion engines using linked CFD and chemical kinetics computations : illustrated by studies of a natural gas burning engine

Yossefi, Danny January 1995 (has links)
No description available.

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