169 research outputs found
Fluid structure interaction modelling of cables used in civil engineering structures
No full textLong, thin, flexible cylindrical elements of large scale structures are heavily influenced by the fluid flow around them. Equally, their movement has an appreciable effect on the fluid flow. This two-way interaction leads to complex dynamic behaviour that can cause fatigue and thus reduce operational lifetime. As demand for longer span bridges and drilling in deeper marine environments increases, research into the best modelling practice of this scenario gains importance. The work described in this thesis establishes a suitable method to model in CFD aero/hydro-elastic behaviour of slender cylindrical elements in large scale structures. In order to achieve this outcome, the author has: modelled the drag crisis on a static cylindrical element; developed a suitable FSI coupling program; combined the drag crisis model with the FSI coupling program and validate against published experimental data. The turbulence formulation used was carefully chosen taking into account the flow features that are important to the onset of the drag crisis. An LES formulation capable of adapting the model constant of the SGS model according to local shear conditions was identied as the best candidate to achieve this aim. The fluid and structural solvers used were loosely coupled by an explicit method that achieved a balance of kinetic energy as well as matching displacement at the moving fluid/solid interface. The integration method and implementation of this coupling strategy was verified by running a test case at low Reynolds number that produced a regular sinusoidal lift function on the cylinder that was kept stationary. The displacement, velocity, and acceleration response produced by the structural solver was compared against a closed solution and found to match with an acceptable level of error. A number of FSI simulations with the cylinder free to move in the cross-flow direction only was carried out. The displacement response was compared against published numerical and experimental data and the importance of having a sufficient spanwise dimension of flow domain was highlighted. Simulations with the cylinder free to move in the along-flow direction aswell as cross-flow direction were carried out. In some simulations where lock-in was observed, the effect of the drag crisis was clearly seen. Energy entered into the system as a result of low drag on the upstream motion of the cylinder caused by the drag crisis. More simulations at different velocities are recommended to define a displacement response curve and make further new observations.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Fluid structure interaction modelling of cables used in civil engineering structures
No full textLong, thin, flexible cylindrical elements of large scale structures are heavily influenced by the fluid flow around them. Equally, their movement has an appreciable effect on the fluid flow. This two-way interaction leads to complex dynamic behaviour that can cause fatigue and thus reduce operational lifetime. As demand for longer span bridges and drilling in deeper marine environments increases, research into the best modelling practice of this scenario gains importance.
The work described in this thesis establishes a suitable method to model in CFD aero/hydro-elastic behaviour of slender cylindrical elements in large scale structures. In order to achieve this outcome, the author has: modelled the drag crisis on a static cylindrical element; developed a suitable FSI coupling program; combined the drag crisis model with the FSI coupling program and validate against published experimental data.
The turbulence formulation used was carefully chosen taking into account the flow features that are important to the onset of the drag crisis. An LES formulation capable of adapting the model constant of the SGS model according to local shear conditions was identied as the best candidate to achieve this aim.
The fluid and structural solvers used were loosely coupled by an explicit method that achieved a balance of kinetic energy as well as matching displacement at the moving fluid/solid interface. The integration method and implementation of this coupling strategy was verified by running a test case at low Reynolds number that produced a regular sinusoidal lift function on the cylinder that was kept stationary. The displacement, velocity, and acceleration response produced by the structural solver was compared against a closed solution and found to match with an acceptable level of error.
A number of FSI simulations with the cylinder free to move in the cross-flow direction only was carried out. The displacement response was compared against published numerical and experimental data and the importance of having a sufficient spanwise dimension of flow domain was highlighted.
Simulations with the cylinder free to move in the along-flow direction aswell as cross-flow direction were carried out. In some simulations where lock-in was observed, the effect of the drag crisis was clearly seen. Energy entered into the system as a result of low drag on the upstream motion of the cylinder caused by the drag crisis. More simulations at different velocities are recommended to define a displacement response curve and make further new observations
Exploring small area demand for grocery retailers in tourist areas
No full textNewing, A., Clarke, G.P. and Clarke, M. 2014. Exploring small area demand for grocery retailers in tourist areas. Tourism Economics, 20(2), pp.407-427This paper uses data from a major loyalty card scheme to draw insights about the characteristics of grocery expenditure by tourists. The authors explore the volume, value and composition of store based visitor expenditure using consumer data from the loyalty card scheme. They focus on grocery spending at selected stores in Cornwall, a popular tourist destination in South West England. Theloyalty card data provide a valuable source rarely available for academic investigations. The authors are able to analyse visitor spend by socio-economic and geodemographic characteristics, drawing a range of comparisons with residential demand from within the store catchment areas. They demonstrate that visitor grocery expenditure is complex and varies by store, destination and type of customer. The paper presents evidence to suggest that the current approaches used to estimate sales uplift and local-level economic impact from visitor demand are unable to account for the complexities of this form of expenditure. Based on these insights, the authors recommend that sophisticated modelling is employed to estimate the impact of visitor expenditure
Evaluating the Diversifying Market for and Viability of Rural Tourism Activity in Japan
No full textThis paper evaluated diversified rural tourism activities from the perspectives of economic viability and endogenous utilization of rural resources and investigated labour productivity. First, we presented a conceptual framework on how to evaluate economic viability and the endogenous mobilization of rural resources. Second, we empirically evaluated economic viability, the supply shift effect of endogenous utilization of rural resources and labour productivity with regard to rural tourism. The main findings are as follows. First, examination of the three main activities, i.e. accommodation, restaurant operation and direct selling of farm products, showed that both full-time and part-time labour input contribute more effectively to better sales than such labour for farm experience services, which means that these activities are viable whereas other activities that provide farming experience services did not yet clearly show evidence of a viable farm business. Second, we could not confirm the supply shift effect of endogenous innovative use of rural resources. Overall, it was evaluated that rural tourism in this country is undersupplied at a social optimal level. In the long run, institutional conditions for market formation and management skills for endogenous innovation in utilization of rural resources should be more intensely developed as a part of rural resource management policy.rural tourism, rural resources, farm diversification, Community/Rural/Urban Development,
Are we catering to the construction industry KM requirements?: A literature synthesis
No full textThe concept of Knowledge Management is now familiar to the construction industry and
various attempts are being made for the effective management of knowledge in the industry.
This paper addresses the importance of people factor and tacit knowledge in construction and
examines the current focus of knowledge management initiatives to find out the alignment with
the industry requirements. Labour and knowledge intensive nature of industry is revealed with
challenging aspects of construction performance. Dominant hard model of human resource
management is uncovered and finally the mismatch between the current focus and industry KM
requirements is unearthe
An overview of the ATLAS High Level Trigger Dataflow and Supervision.
No full textThe ATLAS high-level trigger (HLT) system provides software-based event selection after the initial LVL1 hardware trigger. It is composed of two stages, the LVL2 trigger and the event filter (EF). The LVL2 trigger performs event selection with optimized algorithms using selected data guided by Region of Interest pointers provided by the LVL1 trigger. Those events selected by LVL2 are built into complete events, which are passed to the EF for a further stage of event selection and classification using off-line algorithms. Events surviving the EF selection are passed for off-line storage. The two stages of HLT are implemented on processor farms. The concept of distributing the selection process between LVL2 and EF is a key element in the architecture, which allows it to be flexible to changes (luminosity, detector knowledge, background conditions, etc.) Although there are some differences in the requirements between these subsystems there are many commonalities. An overview of the dataflow (event selection) and supervision (control, configuration, monitoring) activities in the HLT is given, highlighting where commonalities between the two subsystems can be exploited and indicating where requirements dictate that implementations differ. An HLT prototype system has been built at CERN. Functional testing is being carried out in order to validate the HLT architecture
A case study of virtual learning course development in Scottish higher education
No full textVirtual Learning Environments (VLEs) are now an important part of Information and Communication Technology (ICT) strategy in Scottish Higher Educational institutions and beyond. VLEs, which can have a variety of other names such as virtual campuses, interactive web environments and managed learning environments (MLEs) are now considered as part of a group of software, known as learning platforms. The dissertation, which is insider research, examines the non-technical issues involved in VLE course development. The author has been developing a number of VLE courses for two departments in one Scottish Higher Education Institution, using the WebCT VLE. The promotion of learning in the educational context is discussed which examines some of the central claims of the constructivism versus behaviourism debate. A literature review has also been completed on a number of subjects such as Virtual Learning Environments, Managed Learning Environments, and the rise of VLEs in Higher Education, particularly in Scotland. Practical and theoretical definitions of VLE are discussed. A case study has been completed on the author's VLE course development. The thesis reports on a number of issues in the case study. These include the fear factor amongst academics, the range of staff training both in using VLEs and their application to academic subjects, as well as some of the policy and management decisions that were taken at department and university levels. The discussion expands some of the issues raised in the literature review and case study, particularly with regards to the nature of training given to academics, and the promotion of the VLE as a learning tool
The role of tourism promoting community participation in the development of Jiwaka Province in Papua New Guinea
No full textThis master’s thesis explored whether or not tourism can facilitate community development in the Jiwaka Province in the Highlands of Papua New Guinea (PNG). The people of Jiwaka Province, a newly created province, could benefit from tourism if a national tourism policy is implemented at the provincial level. The literature review examined the role of tourism development in less developed countries, indigenous tourism development, tourism policy, indigenous tourism, tourism advocacy and community development. Action research was used to identify the role of tourism in development of the new province to identify the role, if any, that community participation can have in tourism development. It identified the extent of tourism demand for the Jiwaka Province, some obstacles to tourism development in the province, and how people and smaller communities can become involved in tourism development in Jiwaka Province. The research process led to tourism advocacy, where the researcher helped to educate local people in awareness of the potential they possess and the opportunities available for their community to participate in and to promote development through tourism. The qualitative techniques adopted as part of action research to collect data were interviews and participatory observation. Individual and focus group interviews were used, involving 271 participants, including tourism policy officials in Port Moresby, political leaders of Jiwaka Province, Local leaders and community representatives.
The results indicate that the top down approach of the current tourism policy is not effective for tourism development and does not facilitate community participation at the grass roots level. Most local people in Jiwaka Province are very ignorant of the potential and benefits of tourism. There is potential for tourism development, but there are obstacles at all levels of government. Currently, development for all sectors of Jiwaka Province is at an embryonic stage. Therefore, growth in tourism and the Jiwaka community can become a reality over time alongside infrastructural development and other economic advancements.
The key issues preventing community participation in tourism are corruption in the government, limited government funding, security and law and order problems, and issues related to tourism marketing and policy implementation at the national, provincial and district levels. Other issues involve funding from the office of the governor in Jiwaka, delays in establishing the provincial government apparatus in the province due to inefficient government human resource processes in Port Moresby, no tourism office space in the province, infrastructural development, and ignorance of tourism.
The thesis concluded that community tourism development is the only way for tourism development in Jiwaka because of customary land ownership; a bottom-up approach will deliver more benefits to the community than the current top down approach; a government policy/funding vacuum to support community development leading the communities to turn to corporate and NGO support is deeded, as is the need for tourism advocacy. Recommendations are made to the Jiwaka Provincial Government to prioritise tourism, as a key development agent for communities in Jiwaka Province, using a bottom-up approach, which empowers local people and encourages community participation
School Reforms Based on “International Standards” : an Ideal Imbued with National Adaptations
No full textPurpose and research questions For some time, there has been an endeavor in the policy arena to persuade the public with references to the term “evidence-based policy”. The term seems to have its origin in the UK’s election of the Blair government. The evidence-based policy movement emerged from a desire to remove ideology from the policy process and consequently increase the credibility of policy proposals. Subsequently, governments in several member states of the Organisation for Economic Co-operation and Development (OECD) expressed the same assumption of systematic policy knowledge (Botterill & Hindmoor 2012). In this paper, the purpose is to explore some of the salient international policy discourses underpinning school reforms in Western countries, with the current school reform in Sweden used as an example in a context of ongoing reforms in all the Nordic countries. The research questions are: (i) what arguments and actors in the international education arena are relevant to the national reform priorities and what references are considered important for legitimizing the reform? (ii) how can comparative research perspectives contribute to explore aspects of (in) equalities in national school reforms against a backdrop of international educational policy discourses? Theoretical framework Drawing on Vivien Schmidt (2015) and her theory of discursive institutionalism, the missing link in understanding the connection between ideas and collective action is discourse. Within discursive institutionalism, discourse is understood as human interaction through discursive argumentation by which ideas are conveyed and translated. People have both “background ideational abilities”, which help them understand meanings and act within different institutional contexts, and “foreground discursive abilities” , which enable them to deliberate on institutions in a critical way in order to change them. In their discursive argumentation, actors form discourse coalitions, which are basically kept together by their shared ideas and basic principles. For this type of opinion formation, the agents of change use a communicative discourse to argue, deliberate, and persuade people to change their view of an institution, such as the school. Communicative discourses can be both deliberative and persuasive (Author & Non-Author, 2018). The concepts of background and foreground ideas, as well as cognitive and normative ideas and coordinative and communicative discourses, are all conducive when forming an analytic framework for exploring school reforms. Policy ideas communicated through coordinative and communicative discourses represent aspects of power regarding the meaning and purpose of the institution. Three different ways of thinking about the discursive power of ideas can be identified. First, power through ideas is relevant when actors have the capacity to persuade other actors to adhere to a certain viewpoint. Second, power over ideas is demonstrated when certain actors have the capacity to control and dominate the meanings of ideas. Third, and finally, power in ideas is about ideational power in institutionalizing certain ideas at the expense of other ideas—that is, forming dominant discourses about an institutional idea or activity. There are good reasons for combining discursive institutionalism (Schmidt, 2015) and curriculum theory (Deng & Luke, 2008; Author & Non-Author, 2018) in studies on educational reform. Discursive institutionalism contributes to an understanding of how ideas are formed, communicated, and translated into collective action in international arenas, while curriculum theory has more to say about different analytical levels, views of knowledge, and connections between policy ideas and discursive and social practices at the local level. Moreover, a comparative approach contributes to educational studies through its methodology of detailed comparisons of certain phenomena in different arenas, especially at different levels in an educational policy system with consequences for national and local conditions for schooling (Steiner-Khamsi 2012). MethodologyIn 2014, the Swedish government commissioned the OECD to review the quality of the Swedish national compulsory school system, to identify reasons for the decline in the Swedish students’ knowledge achievements, draw on lessons from other OECD countries based on the PISA results, and suggest policy areas for renewed efforts (OECD, 2015). Upon receiving the report from the OECD, the Swedish government’s instruction to the recently established 2015 School Commission was to propose school reforms based on the proposals in the OECD report. The main documents for analysis in this paper is the OECD (2015) report and the official report from the Swedish School Commission (Green Paper 2018:41, 2018).The methodological point of departure is a focus on the policy documents produced by the OECD and especially their country reports. In this case, the Swedish government commissioned the OECD to evaluate the Swedish school system for compulsory school. The task for the OECD was to “identify the main reasons for the decreasing trends in Swedish students’ performance” and to “draw on lessons from PISA and other benchmarking countries/regions with an expert analysis of key aspects of education policy in Sweden” (OECD, 2015, p. 14). The OECD report Improving School in Sweden (OECD 2015) is thus one the main document for exploring an ongoing school reform based on what the OECD considers to be international standards.The analysis is based on document analysis, comprising the following analytical steps of content analysis: (a) reading closely and systematically to identify the main educational discourses in the texts, (b) analyzing the shifts in the justification of the discourses in the texts, and (c) taking the discursive and social aspects into account in understanding the displacements and changes in the discourses.. My understanding of discourses is based on critical discourse analysis (CDA) as outlined by Fairclough (1992, 2010) and Wodak (2008). This framework applies a dialectical approach to the analysis, and given its emancipatory knowledge interest, positions itself within the very practice it theorizes. Policy is in this context viewed as a place for struggles and negotiations. By drawing on Fairclough’s (1992: 64) definition: “Discourse is a practice not just of representing the world, but of signifying the world, constituting and constructing the world in meaning”, the interest is centered on the communicative interactions in terms of coordinated and communicative discourses (Schmidt 2015).Expected results Policy translation—something borrowed, something own, and something rejected. The translation of educational policies to national contexts never occurs in the form of “a whole package”; instead, each policy reform is transformed and recontextualized on the terms of the receiver. Something borrowed: A reform element that Swedish policy actors perceive as attractive to borrow is the OECD (2015) proposal to establish a publicly funded national institute for enhancing teacher and school leader quality. The School Commission (Green Paper 2017:35) has followed up on this suggestion with a similar proposal to establish a national function for teachers’ and school leaders’ development. Two additional official reports have elaborated the details of the proposal (Green Paper 2018:17; Green Paper 2018: 41). Something own: The OECD (2015) report suggests several reform elements to strengthen the national governance of the Swedish school system. The School Commission (Green Paper 2017:35) has proposed a solution that goes further than the OECD proposal. A return to state governance of schools has long been an option in the policy stream (Kingdon, 1995). This was most clearly expressed by the Liberal Party and has now been reintroduced on the political agenda in a national takeover of transnational policy solutions. Something rejected: While the OECD (2015) is concerned about the quality and resources for what it thinks is an overly widespread teacher education organization, and suggests a review of the number of teacher education providers, the Swedish policy actors have rejected this element of the suggested reform. Instead, the School Commission (Green Paper 2017:35) has claimed that there are good opportunities to strengthen the quality of teacher education within the framework of the current structure. Thus, this suggested reform element has been rejected despite “policy evidence” and benchmarked results. </p
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