In turbomachinery, extra excitation forces may result from non-idealised operation conditions and may sometime cause excessive vibrations and unsteady rotor motions. The goal of this thesis is to investigate the effects of such excitation forces. The extra excitation forces investigated here are the Thomas/Alford force due to the blade tip clearance change, the steam excitation force caused by the variation of inlet steam speed and state blade trailing wake and the dominant magnetic pull force due to dynamic eccentricity of the rotor. The main research results in this thesis include: (1) The modelling of the Jeffcott rotor and the 600MW steam-turbine generator. The used in-house ??transient?? program can only handle the circular short bearings with the modified short bearing method while the simulated steam-turbine should be supported by tilting pad bearings. The first critical speeds of systems supported by tilting pad bearings are more approaching to the lab data for all four rotor models while that of journal bearing supported systems are normally lower than the real operating critical speed. (2) Applying three sorts of excitation forces into the single-stage rotor-bearing system. The numerical simulation shows that for the model with each single excitation force, all of these three forces need to reach some limit to force the system into the unsteady state. For all the three forces, higher limits are needed if the machine runs at lower running speeds. Furthermore, unbalance loading also can influence the system behaviours. As the unbalance increases, the system will still stay steady while the spectra become noisier, though the amplitude still low comparing to harmonics. (3) Combing three types of excitation forces into the assembled rotor-bearing system. The numerical simulation shows that the assembled system presents similar vibration responses as the single stage rotor-bearing system. Furthermore, these three forces cannot cancel each other and the combination will unstabilise the system. Meanwhile, the influence of the dominant magnetic pull force is less than other two forces.

The aim of this research was to explore the travel motivations of Taiwanese tourists who visited Australia, their satisfactions, and destination loyalty, as well as examining the relationship between customer satisfaction, need satisfaction, and destination loyalty. This study is important because of the fact that the number of Taiwanese tourists to Australia has decreased since 1999; however, there have not been any academic studies to ascertain the travel motivations of Taiwanese group package tourists who visited Australia, their need satisfaction, and future intentions. Furthermore, the literature on tourist need satisfaction, customer satisfaction and loyalty has been categorised into discrete areas of study, with little integration of these three concepts in the tourism literature. Thus, the relationship between these concepts is an area of theoretical interest that has been examined in this study. To achieve the aims of the research, one research question and 11 hypotheses were developed. The research question specifically explored the travel motivations of the Taiwanese when visiting Australia. Two hypotheses were designed to test the differences between Taiwanese travel motivations and their need satisfaction, and the differences between travel motivation groups. In addition, nine hypotheses were used to examine the relationships between customer satisfaction, need satisfaction, and destination loyalty. A four-stage research methodology was used. Firstly, the study adopted a qualitative approach using focus group interviews of 33 participants to explore the motivations of Taiwanese group package tourists to Australia. Following the qualitative study, two pre tests including a pre and post survey were conducted in order to develop the scales for travel motivations, customer satisfaction, need satisfaction, and destination loyalty of Taiwanese tourists. Finally, a formal pre and post survey was administered. A pre and post survey design was used to consider the potential changes in tourist motivations after the trip. Cluster sampling was used to select the travel agencies, and five travel agencies agreed to participate in this research. The collection of data for the formal survey began in September 2005 and was completed at the end of February 2006. A total of 547 questionnaires were fully completed with a response rate of 72.9%. The validity and reliability of the various scales for push and pull motivations, destination attributes/services, group package tour services, perceived value, equity, emotion, overall need satisfaction, overall satisfaction, and destination loyalty were examined using exploratory and confirmatory factor analysis, as well as Cronbach’s alpha, and all scales were found to be satisfactory. A total of 17 push and 18 pull motivation items were also determined. Taiwanese tourists had the highest travel motivation scores for ‘travelling around the world’, and ‘having a comfortable trip’, and were attracted by certain attributes of Australia, such as the ‘sunshine and scenery’, and ‘a place to go for good value’. The differences between travel motivations and motivation satisfaction were examined using a paired sample t-test, and the hypothesis was partially supported. Based on the results of these t-tests, importance-performance analysis (IPA) was used to analyse the motivation satisfaction levels, and the results showed that the main travel motivations of Taiwanese travellers to Australia were generally satisfied after the trip, with the push motivation factor ‘having a comfortable trip’ and the pull motivation factor ‘sunshine and scenery’ scoring highest on the satisfaction scale. Factor-cluster analysis was further used to segment tourists in regard to their travel motivations. The results revealed that there were four different travel motivation groups. These groups were significantly different in terms of their customer satisfaction and destination loyalty. The importance level of travel motivations of ‘high motivation travellers’ before the trip was high compared to other groups and the customer satisfaction and destination loyalty were also high after the trip. Taiwanese tourists were generally satisfied with their trip to Australia; however, only two tourist groups: the ‘high motivation travellers’ and the ‘comfort/attraction seekers’ showed any interest in revisiting Australia in the future. The relationship between customer satisfaction, need satisfaction, and destination loyalty was also examined using multiple regression analysis. The results confirmed the hypotheses that customer satisfaction had a positive impact on need satisfaction; need satisfaction positively influenced overall need satisfaction; and overall need satisfaction and overall satisfaction both had a positive relationship with destination loyalty. This shows that tourist need satisfaction and customer satisfaction are related, and customer satisfaction is the antecedent of tourist need satisfaction. Furthermore, tourist need satisfaction is influenced by travel experiences, and destination loyalty is influenced by overall need satisfaction and overall satisfaction. This research has contributed to theory, methodology and to practice. A relationship between customer satisfaction, need satisfaction, and destination loyalty was found. As a result, this study has also successfully integrated the concepts of travel motivation, customer satisfaction, need satisfaction, and destination loyalty. A pre and post survey methodology was used in this research to obtain Taiwanese travellers’ original motivations and their satisfaction levels. Finally, the findings concerning the motivations of Taiwanese tourists to Australia, their need satisfaction, customer satisfaction, and destination loyalty have been found to be useful for tourism managers to assist them in making successful business decisions, improving services, and developing new promotional strategies to encourage Taiwanese visitors to travel to Australia.

La connaissance des conditions psychosociologiques dans lesquelles les entrepreneurs décident de la fin de leur carrière renvoie à des enjeux particulièrement cruciaux pour les chercheurs et les praticiens du conseil. Les conséquences de l’arrêt de l’activité entrepreneuriale sont en effet notables à la fois aux plans individuel, macro-économique car liés à la problématique de la cession-transmission de l’entreprise et sociaux au regard des emplois à préserver (Detienne, 2010). La finalité générale de cette thèse était d’éclairer les facteurs psychosociologiques complexes qui sous-tendent la décision du départ à la retraite dans la population des dirigeants propriétaires. Pour ce faire, le présent travail doctoral visait deux objectifs majeurs. Le premier était de développer un inventaire fiable permettant l’analyse précise de la nature et de la structure des raisons conduisant les entrepreneurs à prendre la décision de mettre fin à leur carrière professionnelle. Trois études distinctes portant sur 442 participants au total ont permis la création et la validation de l’Inventaire des Raisons du Processus Décisionnel du départ à la Retraite des Entrepreneurs (IRPDRE), à partir du modèle Push Pull Anti-push Anti-pull de Mullet, Dej, Lemaire, Raïff, & Barthorpe (2000). Le second objectif visé dans l’étude 4 portait sur le test auprès d’un échantillon de 271 participants d’un modèle des déterminants individuels de la perception des raisons sous-tendant le processus décisionnel de l’arrêt de la carrière chez les entrepreneurs. Cette modélisation incluait également l’examen des liens entre l’évaluation des diverses raisons et l’intention de partir à la retraite des entrepreneurs. Au final, les résultats obtenus dans ce programme de recherches ont permis de proposer un outil multidimensionnel fiable permettant d’évaluer finement la perception complexe des facteurs psychosociologiques à l’origine de la prise de décision du désengagement professionnel des entrepreneurs. Ils ont aussi conduit à une meilleure compréhension des différences interindividuelles lors de la prise de décision de fin de carrière dans cette population. / Understanding the psychosociological conditions of entrepreneurs’ decisions to retire is an important issue for researchers and practitioners. Indeed, the consequences of entrepreneurs’ decisions to retire are important at three levels: individual, macroeconomic in that their retirement is linked to the disposal and transfer of their business, and social in that it affects employment (Detienne, 2010). The overall purpose of this doctoral research was to analyze the psychosociological factors underlying the retirement decision in this specific population. The study had two main objectives. The first was to provide researchers and practitioners with an original and reliable self-report questionnaire to assess the nature and form of the reasons underlying the retirement decision process. Three studies, with a total of 442 participants, were conducted to develop and validate the Reasons for Entrepreneurs’ Retirement Decision Inventory (RERDI), based on the Push Pull Antipush Anti-pull view (Mullet, Dej, Lemaire, Raïff, & Barthorpe, 2000). A fourth study involving 271 participants was carried out to achieve the second objective, which was to test a model of individual determinants of the reasons underlying the retirement decision process. This model also examined the relationships between the evaluation of the reasons and the intention to retire. Finally, the results of these studies allow us to propose a multidimensional and reliable tool to assess in detail the complex perception of the psychosociological factors underlying entrepreneurs’ decisions to retire. The results also provide a better understanding of interindividual differences in this retirement decision.

Submitted by Ana Caroline Costa (ana_caroline212@hotmail.com) on 2018-11-30T18:44:39Z No. of bitstreams: 2 Dissertação - Thaylla Horbylon Nascimento - 2017.pdf: 2748481 bytes, checksum: 12679d6d81f935cee0a82be36ee7480a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-12-03T13:14:23Z (GMT) No. of bitstreams: 2 Dissertação - Thaylla Horbylon Nascimento - 2017.pdf: 2748481 bytes, checksum: 12679d6d81f935cee0a82be36ee7480a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-12-03T13:14:23Z (GMT). No. of bitstreams: 2 Dissertação - Thaylla Horbylon Nascimento - 2017.pdf: 2748481 bytes, checksum: 12679d6d81f935cee0a82be36ee7480a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-12-12 / Outro / Paracoccidioides comprises the genus of fungi causing paracoccidioidomycosis. The research of new treatments, especially those based on inhibition of metabolic pathways important for microorganisms has gained prominence and the aspartate pathway, necessary for the biosynthesis of threonine, isoleucine and methionine in microorganisms, is not found in humans. Catalyzing the second step of this pathway, we found aspartate semialdehyde dehydrogenase (ASADH), which has not yet been characterized in Paracoccidioides spp. and has no substituents in its catalytic function in the aspartate pathway. Thus, it is of interest the determination of its biological properties experimentally that their biological properties be determined experimentally. ASADH from Pb18 was cloned into vector pGEX-4T3, expressed in E. coli Stellar cells and purified on a glutathione-sepharose column. Then, antibodies were produced and used in Western blot assay to confirm protein expression. The pull-down-GST assay was performed and allowed the identification of complexes of interactions between ASADH and soluble proteins present in total protein extract of the yeast form of Pb18. Interactions with proteins of several functional categories, among them those related to the metabolism of threonine, isoleucine and methionine, were found, reinforcing the performance of ASADH in the amino acid biosynthesis of Pb18, as well as proteins related to substrate supply to the aspartate pathway and proteins that use metabolites of this pathway. Interactions with proteins involved in other metabolic pathways were also observed, as well as unprecedented interactions, suggesting the importance of ASADH in the functional processes of microorganisms. / Paracoccidioides compreende o gênero de fungos causadores da paracoccidioidomicose. A pesquisa de novos tratamentos, sobretudo aqueles baseados em inibição de vias metabólicas importantes para micro-organismos, tem ganhado destaque e a via do aspartato não é encontrada em humanos. A via do aspartato é necessária para a síntese de treonina, isoleucina e metionina. Catalisando o segundo passo dessa via, encontramos a aspartato semialdeído desidrogenase (ASADH), que ainda não foi caracterizada em Paracoccidioides spp. e não possui substituintes em sua função catalítica na via do aspartato. Assim, é de interesse que suas propriedades biológicas sejam determinadas experimentalmente. A ASADH proveniente de Pb18 foi clonada em vetor pGEX-4T3, expressa em células E. coli Stellar e purificada em coluna de glutationa-sefarose. Em seguida, anticorpos foram produzidos e utilizados em ensaio de Western-blot para confirmar a expressão proteica. O ensaio de pull-down-GST foi realizado e permitiu a identificação de complexos de interações entre a ASADH e proteínas solúveis presentes em extrato proteico total da forma de levedura de Pb18. Foram encontradas interações com proteínas de diversas categorias funcionais, dentre elas relacionadas ao metabolismo de treonina, isoleucina e metionina, reforçando a atuação da ASADH na biossíntese de aminoácidos de Pb18, bem como proteínas relacionadas ao fornecimento de substrato para a via do aspartato e proteínas que utilizam os metabólitos dessa via. Também foram observadas interações com proteínas envolvidas em outras vias metabólicas, assim como interações inéditas, sugerindo a importância de ASADH nos processos funcionais de micro-organismos.

Implants such as intramedullary nails or cancellous screws are used to mechanically stabilize fractures in bone. They provide reinforcement to the bone if they find good purchase in cancellous bone. Not all implants hold enough loads for mechanical stability and pull-out or cut-out may happen in some cases. This is linked to the interface between the bone and the implant. Computer modelling techniques are used to investigate both the effects of cut-out in a femur model, and the pull-out forces of cancellous bone screws. The bone geometry was based on CT scanned cancellous bone and converted using Mimics® software. The finite element models were produced in ANSYS®. Simple bone models were used to examine a fractured femur under standard gait loading. These models were continuum models and idealised the screw to bone interface in order to ease computational demand. The models were used to investigate the ideal positions of intramedullary devices lag screws on an anterior-posterior view of the implant location. In accordance with literature, an inferior-central or central-central position was the best position of the lag screw, while a superior-anterior or inferior-anterior position was adverse. The introduction of multi-scale modelling in order to investigate cut-out with a discrete bone model was not achieved. Discrete cancellous bone models were used to examine some of the cancellous screw characteristics, including pitch, inner diameter and proximal half angle, while a cancellous screw was also studied using a model of cancellous bone with a range of bone densities. The calculated reaction force for a pull-out of 0.2mm shows the influence of some parameters. Change in the proximal half angle increased the stiffness and strength by about 15% in line with the experimental findings of others, while apparent density changes of 2.5% increased the forces threefold. A significant reduction in reaction force was observed when a particular screw geometry in lower apparent density bone was modelled and rotated through 180° on a plane. Examination of the geometry of the bone/screw interface shows that in certain positions there is very little cancellous bone to support the implant. This will lead to low strength and is very difficult to predict. The same models were used to examine the effect of increasing bone stiffness adjacent to the implant and the use of a cement layer to augment the screw model. The increasing stiffness concluded that an increase in pull-out stiffness can be achieved, even in low quality bone, while the cement augmentation showed a significant increase in pull-out strength, though it was idealised as bonded to the bone and screw.

Den svenska urbaniseringen har medfört att cirka hälften av kommunerna i Sverige krymper i befolkningsantal. Detta har inneburit utmaningar och svårigheter för de krympande kommunerna att hitta den kompetens som krävs för att kunna utföra de tjänster de är ålagda att erbjuda sina medborgare.Syftet med denna rapport var att undersöka varför medarbetare inom inlandskommun X väljer att påbörja, fortsätta och eventuella avsikter till att avsluta sin anställning. Genom att intervjua medarbetare inom bristyrken inom offentlig sektor framkom att arbetsmässiga faktorer såsom arbetsmiljö, arbetsbelastning och arbetssysslor i kombination med platsbundna faktorer såsom närhet till natur, jakt och friluftsliv bidrar till dessa intentioner.

If the rotor of an induction motor is not concentric with the stator then an electromagnetic force is generated in a direction that will increase the eccentricity. This is called unbalanced magnetic pull (UMP). The first part of the work presented in this dissertation develops theoretical models which allow the calculation of the UMP in cage induction motors due to static rotor eccentricity. These account for any winding configuration including parallel stator winding connection. The second part of the work verifies the models experimentally using two different cage induction motors. The agreement between predicted and measured values of UMP and line current is found to be good. The investigation leads to several new aspects of the damping effects of parallel stator windings and the cage rotor being highlighted.

An increasing interest in non-canonical nucleic acid structures has drawn the attention of the scientific community during the last few decades. One such structure, the G-quadruplex, has been the focus of an increasing number of scientists as G-quadruplexes are believed to play a role in biological processes such as telomere integrity and gene expression. Their existence in vivo is largely unproven but they have stimulated a lot of research into small molecules that interact with them. The development of a new class of such molecules is described in this thesis. A member of this family showed to be very selective in stabilising one particular G-quadruplex. The further development of another family of G-quadruplex interacting small molecules is also presented in this thesis and some of their effects in cellulo were assessed. Based on the scaffold of this family, an affinity probe was developed, which can mediate the isolation of its nucleic acid targets from human cells. This is the first example of the use of a small molecule with an affinity tag that has been used to isolate a nucleic acid target in a structure specific manner from human cells.

Mobile commerce (m-commerce) has created the opportunity to transact anywhere, anytime, transcending barriers of space and time. However, this freedom has been found to be intrusive in the lives of mobile users, acting counterproductively to trust building and exacerbating the reluctance to adopt m-commerce. The research design was a quantitative study that pivoted around the concept of location-based services (LBS) for mobile users and was focused on understanding specific behaviours around usage and trust under pre-determined conditions of connecting (particular place, particular time), push and pull mechanisms, brand loyalty and social network recommendations. The study was conducted through an online questionnaire with a non-probability sample of 189 individuals. Factors including push and pull LBS mechanisms, brand loyalty and social network recommendations were found to exhibit significant influence on mobile users trust and propensity to transact in m-commerce. No empirical support was found between the connecting conditions with mobile users and adoption of m-commerce, eliciting future research in this area. These results contribute to the body of research regarding mobile commerce by extending the existing understanding of its use through application with push and pull location-based services. / Dissertation (MBA)--University of Pretoria, 2012. / Gordon Institute of Business Science (GIBS) / unrestricted

Sweden’s population is growing and has been growing a lot since the year 2000. This growth is expected to continue. Although Sweden´s population is increasing, this is not the case for all municipalities. Some rural municipalities are decreasing in population, like the four Torne valley municipalities. These four municipalities are Kiruna, Haparanda, Pajala and Övertorneå. This study is quantitative and is based on population statistics from the database SCB. The aim of this study is to examine how the population has changed in volume and composition during the years 2010 to 2019 in the four Torne valley municipalities in Sweden. This study is also going to discuss the possible reasons behind the population change and relate it to theories and other studies. The results show that all the Torne valley municipalities had a negative population growth in the last ten years. The age and gender share has also changed. The results also show that the gender balance in the different age groups are unbalanced, for example there are more women than men aged 75 years or older. Over the past ten years the amount of people aged 65 or above has increased, meanwhile the amount of working-age people has decreased. This has led to a higher dependency ratio for all municipalities. Furthermore, the results show that the international migration has been important for all municipalities, without the international migrants all municipalities would have a larger decrease of population.