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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.
181

The Reason to Return : Destination loyalty and the push factors

Cerpez, Dario, Johannesson, Emma January 2009 (has links)
<p><p>The reason to return is a phenomenon which tells us that many people want to travel back to a destination they visited before. Even if there are changes in the society with the New tourist who seeks for the authentic, this essay is proving that there still is a dominance of repeat tourism and search for belonging and safety. That implication shows evidence that there still are remaining from old tourism about security with the destination and so on. Further, investigation tells us about the returning tourists, their driving forces and push-factors that create a will for tourists to return. Is it a question of how loyal tourists are to the destination, attitudes and/or tradition when planning the trip? We have made a survey that covers why tourists travel and what impacts are created during their decisions. Also included are the questions about the will of return and the reasons why. Having children proved to be a crucial part of the decision making process, where parents chose destinations out of the children-oriented places. Returning to a destination, on the other hand, is a product of safety-seeking together with a positive experience and beautiful surroundings, all weaved up to raison d'être - just to be.</p></p>
182

A Study on the Relationship between the Air-Sea Density Flux and Isopycnal Meridional Overturning Circulation in a Warming Climate

Han, MyeongHee 10 May 2011 (has links)
The Meridional Overturning Circulation (MOC) plays an important part in the Earth's climate, but the mechanisms that determine MOC response to climate change remain unclear. In particular, the relative importance of the adiabatic and diabatic dynamics in MOC is still under debate. This study aims to explore the relationship between the air-sea density flux and isopycnal MOC, and examine the possibility of diagnosing the adiabatic component of MOC from the air-sea density flux. This is done here using the concept of the "push-pull" mode, which consists of the adiabatic push into the deep ocean in the Northern Hemisphere and pull out of the deep ocean in the Southern Hemisphere. The evolutions of the isopycnal MOC and the "push-pull" mode are qualitatively similar. The maximum streamfunctions of the "push-pull" modes and isopycnal MOC both decrease by 3-5 Sv during 100 years, and their decrease is very similar to each other in the deep layers. In particular, the slope of the downward linear trend in the maximum is about -5 Sv per 100 years in both the "push-pull" modes and isopycanl MOC at the equator. The decrease in actual isopycnal MOC is faster at heavier densities than that at lighter densities. The first EOF mode of eigenvectors of the "push-pull" mode explains less percentage of variance than in the case of the isopycnal MOC at the equator. The detection of the global changes in MOC from the surface fluxes alone is feasible, if the surface fluxes are measured with sufficient accuracy.
183

Reducing WIP Inventory of Production Line in AQ Segerström &amp; Svensson AB

Yuvaraj, Vasanth Raj, Zhang, Sifei January 2013 (has links)
The major objective of present study is to find out the sources which cause higher Work in Process (WIP) in the production line. In which a detailed analysis is performed in the area of inventory, reorder point, Takt time, and Kanban. All the analyses are based on the data obtained from the company’s ERP system and have been used to run some scenarios during the analysis.Lots of problems are responsible to cause higher WIP. But current report only focuses and concentrates in leveling the work load, implementing pull system, suggesting reorder point and Takt time.The current situation is described through Value-stream Map (VSM) and the impact cost matrix is used to show the impact of each problem in the production line in terms of costs. In the analysis chapter, root cause method has been used in order to show the cause and effect of higher WIP. Detailed analyses together with explanations are listed by orders. Therefore, three major suggestions are proposed and the future VSM is plotted to show the effect and change of the suggestions which helps to improve the current situation by eliminating the waste.
184

Greffage de molécules 'push-pull' sur germanium: vers la passivation diélectrique

Lefèvre, Xavier 22 October 2012 (has links) (PDF)
Les excellentes propriétés électroniques du germanium limitées par la faible qualité isolante de son oxyde rendent le développement de nouveaux matériaux diélectriques nécessaires. En outre, la sensibilité du germanium requiert la création d'une couche passivante de surface pour le protéger. Bien que de nombreuses études soient réalisées pour le développement de nouveaux diélectriques inorganiques, ce projet de recherche en rupture concerne la conception, la réalisation et le développement de film mince diélectrique organique passivant sur le germanium pour des applications en nanoélectronique. Le travail réalisé porte principalement sur la synthèse de nouvelles molécules " push-pull " (systèmes conjugués linéaires portant de part et d'autres un groupe donneur et un groupe accepteur) et sur la fonctionnalisation du germanium. Plusieurs nouveaux systèmes donneur-accepteur ainsi que des systèmes conjugués linéaires contenant une fonction d'ancrage ont été synthétisés selon de nouvelles voies. En particulier, une série de dérivés azobenzène contenant différents accepteurs (groupes fluorés, pyridinium, nitro) et donneurs (amines, alcoxyl) ainsi que des fonctions d'ancrage variées (thiol, acide carboxylique, sel de diazonium, triazene) a été obtenue. En parallèle, la préparation et la fonctionnalisation de surfaces de germanium ont été étudiées. Un nouveau procédé permettant d'enlever l'oxyde natif de la surface et d'obtenir des surfaces halogénées de faible rugosité a été développé. Les substrats de germanium ont été fonctionnalisés par des thiols mais également par des sels de diazonium. Ce nouveau processus de greffage spontané a permis d'abaisser considérablement le temps de réaction (15 minutes de greffage spontané des sels de diazonium contre 3 jours pour la formation de monocouches auto-assemblées de thiols) tout en travaillant dans des conditions douces. Les films minces ainsi obtenus présentent une stabilité comparable à celles des monocouches de thiols. Des systèmes conjugués linéaires ont été greffés à la fois sous forme de thiol et sous forme de sels de diazonium afin de déterminer l'influence du noyau aromatique sur la formation du film et sur ses propriétés. Enfin, les systèmes " push-pull " ont également été greffés. Des premières études électroniques sur or avec les systèmes conjugués linéaires ont été réalisées. Ces études ont été étendues au germanium et laissent envisager des résultats significatifs avec les molécules " push-pull ".
185

Pull Production System Improvements : Pull Production System Improvements In GKN Driveline AB

Wang, Xiaoyan January 2012 (has links)
As the effort of today’s industries to continuously move towards lean production, pull production system has been developed as one possible solution of lean. It is popularly known in the industry world, and is indeed a proven technique to achieve substantial savings on inventory, production cost incurred by manufactures all over the world. However, a careful understanding of pull production systems is required to access its suitability to a particular production setup. It is necessary to develop a proper way to implement pull production systems.             This study is based on a real life scenario in a leading driveline manufacturing company. The production system is studied in detail as regard to its production characteristic. A theoretical review is first made as research foundation. A careful analysis study within the company is conducted with all the existing constrains to figure out improvement opportunities. Eventually, from the applicability point of view, proposals of future pull production system implementation have been developed. The objective of the proposals is to minimize the identified weaknesses of the current system, including long lead time, low flexibility and unconnected flow.
186

Migration of African-trained physicians abroad : a case study of Saskatchewan, Canada

Kogo, Seraphine 01 June 2009
Several factors inform health professionals decisions to migrate from developing to developed countries to practice their profession. This study explores the Push and Pull factors that informed African-trained physicians decisions to migrate to the province of Saskatchewan, how well they integrated into their new working environments upon arrival and how that might contribute to future migration and retention in Saskatchewan. Based on questionnaire surveys and face-to-face interviews, this study identified differences in the relative importance of precipitating factors for physicans from South, North and Other African nations. Although the majority of African-trained physicians for the study indicated that profession-related push factors were the precipitating factors for their migration, a smaller number did not cite these as important. Most respondents for the study integrated well into the health care system and have remained at their current location of practice because of the support they received from colleagues at their work places.
187

Visible relations in online communities : modeling and using social networks

Webster, Andrew 21 September 2007
The Internet represents a unique opportunity for people to interact with each other across time and space, and online communities have existed long before the Internet's solidification in everyday living. There are two inherent challenges that online communities continue to contend with: motivating participation and organizing information. An online community's success or failure rests on the content generated by its users. Specifically, users need to continually participate by contributing new content and organizing existing content for others to be attracted and retained. I propose both participation and organization can be enhanced if users have an explicit awareness of the implicit social network which results from their online interactions. My approach makes this normally ``hidden" social network visible and shows users that these intangible relations have an impact on satisfying their information needs and vice versa. That is, users can more readily situate their information needs within social processes, understanding that the value of information they receive and give is influenced and has influence on the mostly incidental relations they have formed with others. First, I describe how to model a social network within an online discussion forum and visualize the subsequent relationships in a way that motivates participation. Second, I show that social networks can also be modeled to generate recommendations of information items and that, through an interactive visualization, users can make direct adjustments to the model in order to improve their personal recommendations. I conclude that these modeling and visualization techniques are beneficial to online communities as their social capital is enhanced by "weaving" users more tightly together.
188

60 Watts Broadband Push Pull RF Power Amplifier Using LTCC Technology

Jundi, Ayman 23 September 2013 (has links)
The continuous increase in wireless usage forces an immense pressure on wireless communication in terms of increased demand and spectrum scarcity. Service providers for communication services had no choice but to allocate new parts of the spectrum and present new communication standards that are more spectrally efficient. Communication is not only limited to mobile phones but recently attention has been given to intelligent transportation systems (ITS) where cars will be given a significant place in the communication network. Vehicular Ad-Hoc Network (VANET) is already assigned a slice of the spectrum at 5.9GHz using the IEEE802.11p standard also known as Dedicated Short-Range Communication (DSRC); however, this assignment will have limited range and functionality at first, and users are expected to depend on existing wireless mobile channels for some services such as video streaming and car entertainment. Therefore, it is essential to integrate existing wireless mobile communication standards into the skeleton of ITS at launch and most probably permanently. An investigation was carried out regarding the existing communication standards including wireless local area networks (WLAN) and it was found that frequency bands from 400MHz up to 6GHz are being used in various regions around the world. It is also noted that current state of the art transceivers are composed of several transmitter front-ends targeting certain bands and standards. However, the more standards to be supported the more components to be added and the higher the cost not to mention the limited space in mobile devices. Multimode Multiband (MMMB) transmitters are therefore proposed as a potential solution to the existing redundancy in the number of front-end paths in modern transmitters. Broadband amplifiers are an essential part of any MMMB transmitter and they are also among the most challenging especially for high power requirements. This work explains why single ended topologies with efficiencies higher than 50% have a fundamental bandwidth limit such that the highest frequency of operation must be lower than twice the lowest frequency of operation. Hence, Push-Pull amplifier topology is being proposed as it was found that it has inherent broadband capabilities exceeding those of other topologies with comparable efficiency. The major advantage of Push-Pull power amplifiers is its capability of isolating the even harmonics present in the even mode operation of a Push-Pull amplifier from the less critical odd mode harmonics and the fundamental frequency. This separation between even and odd signals comes from the inclusion of a Balun at the output of push-pull amplifiers. Such separation makes it possible to operate amplifiers beyond the existing limit of single ended power amplifiers. To prove the concept, several Baluns were designed and tested and a comparison was made between different topologies in terms of balance, bandwidth and odd and even mode performances; moreover, to illustrate the concept a Push-Pull power amplifier design was implemented using the multilayer Low Temperature Co-fired Ceramics (LTCC) technology with a bandwidth ratio of more than 100%.
189

Was it your choice? : a study about ethnic entrepreneurs in Möllevången

Hamed, Abber, Keblawi, Amal January 2012 (has links)
Entrepreneurship among immigrants is steadily increasing in Europe and is playing an increasingly important role in the social and economic structure of European cities. In Malmö, Möllevången the ethnic businesses are continuingly thriving in the Swedish society. They fill a versatile and in many ways unique feature. They also fill gaps in the market; help to give new life to downturn urban areas, offering new products and services. But the questions are, are these immigrants forced to become entrepreneurs or have they chosen to be? What factors lie behind? How did they start their business in the beginning? To answer these questions, a qualitative method was used, where the semi- structured interviews with 5 respondents from different backgrounds were recorded, such as Iraq, Iran, Palestine, Poland and Serbia. The analysis and conclusion of this study showed that ethnic entrepreneurs both chose and were forced to enter self-employment. The five respondents mentioned several factors that had motivated them to self-employ, which are language barriers, discrimination, traditions, low wages, education and to be your own boss. The respondents did not follow theories used in this study about how entrepreneurs start their own business, but instead followed other stages that we call “Stages of starting your own for ethnic entrepreneurs”.
190

Macroeconomic Shocks and Monetary Policy : Analysis of Sweden and the United Kingdom

Gajic, Ruzica January 2012 (has links)
External economic shocks cause domestic macroeconomic aggregates to fluctuate. This may call for a macroeconomic policy intervention. Since the early 1990s an increasing number of countries have adopted an inflation targeting framework. In reality, inflation targeters do not have perfect information when determining the interest rate in order to maintain their goal of price stability and stable economic growth. Therefore it is relevant to understand how shocks affect the domestic macroeconomic aggregates theoretically and investigate whether the theoretical predictions hold empirically. I use the New Keynesian model by Clarida, Galí and Gertler from 1999 and investigate explicitly the theoretical effects of expected and unexpected supply and demand-side shocks on the monetary policy instrument and the two monetary policy target variables – the interest rate, output gap and inflation rate. By analysing the impulse-response functions of a structural VAR model applied to quarterly Swedish and British data from 1994 to 2011, I test empirically the theoretical predictions according to the New Keynesian model. I find that the empirical results are in line with the theoretical predictions.

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