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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.
21

Apparatus and test methods for measuring the impact of golf balls on turf and their application in the field

Haake, S. J. January 1989 (has links)
An apparatus was developed to project spinning golf balls directly onto golf greens. This employed a modified baseball/practice machine with two counter-rotating pneumatic wheels. The speed of the wheels could be varied independently allowing backspin to be given to the ball. The ball was projected into a darkened enclosure where the motion of the ball before and after impacting with the turf was recorded using a still camera and a stroboscope. The resulting photographs contained successive images of the ball on a single frame of film. The apparatus was tested on eighteen golf courses resulting in 721 photographs of impacts. Statistical analysis was carried out on the results of the photographs and from this, two types of green emerged. On the first, the ball tended to rebound with topspin, while on the second, the ball retained backspin after impact if the initial backspin was greater than about 350 rads-1. Eleven tests were devised to determine the characteristics of greens and statistical techniques were used to analyse the relationships between these tests. These showed the effects of the green characteristics on ball/turf impacts. It was found that the ball retained backspin on greens that were freely drained and had less than 60% of Poa annua (annual meadow grass) in their swards. Visco-elastic models were used to simulate the impact of the ball with the turf. Impacts were simulated by considering the ball to be rigid and the turf to be a two layered system consisting of springs and dampers. The model showed good agreement with experiment and was used to simulate impacts from two different shots onto two contrasting types of green.
22

Learning on two campuses : students' transition experiences in a China-UK articulation programme

Hou, Junxia January 2011 (has links)
This thesis presents a longitudinal ethnographic research study of the intercultural transition experiences of 50 engineering students in the China- UK Articulation programme. The aim is to explore the factors that have influenced their transition and the impact of their transition on the educational context on both campuses. The field work was carried out over fifteen months in China and the UK. Data have been collected mainly through participants observations, document analysis and in-depth interviews with 16 Chinese programme students (3 rounds), 5 home students, 2 international students, 10 Chinese academic and administrative staff, 8 British academic and administrative staff and 2 parents. Data were analysed by using the data analysis principles advocated in grounded theory.
23

Enhancing participation and performance in physical activity through primary level physical education : the role of physical literacy

Giblin, Susan January 2016 (has links)
Overall, this thesis provides a number of evidence-based studies to address the requirements and methods through which physical skills are developed and assessed in primary school children. With practical requirements at the fore, this work serves to aid teachers and educators in delivering a standardised, evidence based curricula of comprehensive physical education. Additionally, the thesis raises questions about the adequacy of existing theory, policy and practices that lack the empirical validation and offers a useful insight into how this might be rectified in the future.
24

Multilevel molecular modelling of structure-function relationships in enzymes

Singh, Warispreet January 2016 (has links)
Proteins are large flexible molecules and conformational dynamics is one of their fundamental properties which correlate the protein’s structure and function [1] [2]. The crystal structure of biomolecular systems such as enzymes reveals the important atomistic details in terms of the ligand binding and possible mechanism albeit providing no information about how conformational flexibility and dynamics influences the protein structure and its key determinants. There is no information regarding the electronic structure and the chemically relevant components of the enzymes and how the protein environment affects the electronic structure. In order to provide understanding of how the conformational flexibility influences structure-function relationships of the enzymes, we applied classical molecular dynamics simulations using Gromacs [3] [4] [5] and Amber [6] [7] packages. The effect of the protein environment on the electronic structure of the active site were studied using Quantum Mechanics and Molecular Mechanics (QM/MM) [8] using ONIOM [9] [10, 11] implemented in Gaussion09 [12] [13]. Tyrosylproteinsulfotransferase (TPST): TPSTs catalyze the transfer of negatively charged sulfate group from 3’-phosphoadenosine 5’-phosphosulfate (PAPS) to the hydroxyl group of a tyrosine residue of polypeptide to form a tyrosine O4-sulfate ester [14]. The binding of the substrate peptide showed more open conformation in Tyrosylproteinsulfotransferase-2 (TPST-2) enzyme in contrast to the crystal structure [15] [16]. There were identification of new hydrophobic interactions responsible for the stabilization of the enzyme dimer [16]. The binding of the substrate and cofactor to the apoenzyme contributed to the stability of the whole active complex, influenced the local interactions in the binding site and importantly, affects the pattern of the correlated motions in the entire molecule [16]. NirE an S-adenosyl-L-methionine dependent Methyltransferase: The NirE enzyme catalyses the transfer of a methyl group from the S-adenosyl-L-methionine (SAM) to uroporphyrinogen III and serves as a novel potential drug target for the pharmaceutical industry. The binding of the substrate contributes to the stabilization of the structure of the full enzyme complex [17]. The conformational changes influence the orientation of the pyrrole rings of the substrate [17]. The mutations of binding and active site residues leads to sensitive structural changes which influence binding and catalysis [17]. Matrix metalloproteinase-1 (MMP-1): The molecular dynamics studies on the Matrix metalloproteinase-1 (MMP-1) were in good agreement with the experimental observation that in the MMP-1•THP (Triple Helical Peptide) X-ray crystallographic structure MMP-1[18] is in a "closed" conformation [19]. The interactions of the THP with both the CAT and HPX domains of MMP-1 are dynamic in nature, and the linker region of MMP-1 influences the interactions and dynamics of both the CAT and HPX domains and collagen binding to MMP-1 [19]. The mutations in the MMP-1 have distinct impact on the correlated motions in the MMP-1•THP. An increased collagenase activity corresponded to the appearance of a unique anti-correlated motion and decreased correlated motions, while decreased collagenase activity corresponded both to increased and decreased anti-correlated motions. Non-heme Fe2+ and 2-oxoglutrate (2OG): The non-heme Fe2+ and 2-oxoglutrate (2OG) dependent dioxygenases such as FTO, AlkB, PHF8 and KIA1718 perform important tasks in homeostasis through the methylation of DNA and histone proteins. The linker region shows increase conformational flexibility and dynamics in PHF8 and KIA1718 and is important for the catalysis. The jelly roll motif structure also showed conformational stability for all demethylases and indicates its vital role in maintaining the iron geometry in the active site. The N domain of the FTO enzyme and the L1 loop region showed increased conformational flexibility and dynamics. The QM/MM optimized structure of reactant complex showed the effect of the conformational flexibility. An important insight into the structure function relationship of different enzymes has been obtained by applying a large number of Atomistic Molecular Dynamics Simulations and Quantum Mechanics/Molecular Mechanics to different enzymes which cannot be gained experimentally. The effect of conformational dynamics, flexibility and important interactions of the active site residues can be used in chemical biology and biotechnology for structure based drug design and in the engineering of novel biocatalyst.
25

'Am I doing it right?' : exploring the practice of supervising master's dissertation students

Macfadyen, Ann January 2016 (has links)
Students undertaking taught master’s programmes comprise the largest group within postgraduate education. Dissertation supervision is recognised as being a key influence on student attainment, but there is relatively little research into this aspect of academic practice (Bruce and Stoodley, 2013). This action research project, which involved collaboration with 25 master’s dissertation supervisors in health and education, identified that it is one of the aspects of the job that even experienced academics feel least prepared for and worry about. In order to enable them to articulate their previously untapped expertise of supervision, I created a ‘communicative space’ (Kemmis and McTaggert, 2005) in which academics shared their experiences, reflected with one another on the nature of supervision, and developed materials for new supervisors. They recognised that supervisory expertise is not a definable body of knowledge but a process which involves situational judgement. Together we articulated five key messages for other supervisors which outline the complexities involved in this role. Building upon these findings, I constructed a new three sided model, which conceptualises the process of supervision. The new model developed through my research explains how these supervisors practice, using a holistic approach to promote students’ development. The core element is the supervisor’s ongoing assessment of a student’s readiness, motivation and individual situation. In response to this assessment, supervisors balance three functions in promoting student growth: Facilitating, Nurturing and Maintaining Standards. Facilitating encourages student growth through challenge or stimulation. Nurturing involves the provision of support and reassurance within a safe space in which this growth can occur. Maintaining standards ensures that academic and professional rigor are preserved. The key messages and new model contribute to the established knowledge within supervisory pedagogy and are of benefit both in the preparation of new supervisors and for future development of this academic practice.
26

Mesoscale modelling of block copolymer systems

Pinna, Marco January 2009 (has links)
This thesis is dealing with a set of physical phenomena occurring in various block copolymer systems and trying to understand them by means of computer simulation. In the course of the work Cell Dynamics Simulation (CDS) was implemented as a computer program and further developed when necessary. The choice of CDS is due to the fact that it is a simplest minimal model of the Ginzburg-Landau type and its ability to describe complex physical situations was debated. The thesis clarifies this issue by a systematic study of diblock copolymers subjected to the external influences such as electric field, shear flow, confining surfaces and nanoparticles. The thesis results prove that CDS can describe such complex phenomena rather well and therefore, is a complementary method to other more elaborate techniques. The thesis provides a ground for a future development of a tandem simulation where a very fast CDS method can be used as a precursor to more elaborate but slow techniques as, for instance, Dynamics Self-Consistent Field Theory.
27

Organisational factors in RFID adoption, implementation, and benefits

Dabo, Al-amin Abba January 2017 (has links)
This study investigates the impact of organisational and technological factors within pre-adoption, implementation, and post-implementation phases of RFID system deployment. In the pre-adoption phase, the study examines factors that drive and hinder organisations’ decision to adopt RFID. In the implementation phase, the study investigates the impact of organisational factors (business size, strength of culture, and business process re-engineering) on influencing the implementation processes of RFID. In the post-implementation phase, the study investigates how the benefits derived from RFID implementation interact with organisational factors (business size, strength of culture, and business process re-engineering) and RFID-related factors (product unit level of tagging, RFID implementation stage, and organisational pedigree in RFID). This study was motivated by the lack of (i) an advisory framework which considers quantifiable firm characteristics and the costs and benefits of implementing RFID, in yielding advice to guide decisions on RFID adoption, and (ii) a framework that covers the complete processes of RFID project deployment (from adoption decision to benefits derived) in yielding advice to guide decisions on RFID adoption. This study is achieved using a two-phase research approach: questionnaire survey of organisations that have adopted or plan to adopt RFID and case studies of organisations that have integrated RFID into their business processes. In addition, a thorough review of existing literature on RFID in different industrial settings was conducted. The key findings from the study indicate that RFID adoption is driven by factors from technological, organisational and environmental contexts and that the adoption, implementation and benefits of RFID are influenced by organisational culture strength, business size, and BPR. It was found that strong cultures, organisational size and BPR are all positively correlated with RFID adoption decisions, implementation and benefits. Potential contribution towards the existing body of knowledge is through highlighting the significance of organisational culture strength, business size, and BPR in providing a platform in which RFID will be accepted and implemented successfully to achieve maximum derivable benefits.
28

Integrated performance-reliability optimisation of systems with multi-level redundancies

Ikegwuru, Okachi January 2016 (has links)
Redundancy allocation, in the context of reliability driven design, is the process of multi-objective optimisation of system configuration with reliability and cost related objectives. Large systems, of any type and discipline, can be divided into several subsystems comprising modules and components. Such a hierarchical form of system arrangement is regarded as multilevel configuration. These systems have the performance capability beyond traditional binary reliability framework of either completely working or totally failed. Large systems normally have redundancies at different levels. In current practice, multi-level redundancy allocation takes place sequentially. This is mainly due to lack of a robust optimisation method capable of delivering large scale redundancy allocation problems. Development of such methods leads to design of enhanced systems with better performance in terms of cost and reliability. The overall aim of this project is to develop a method for multi-state reliability optimisation of large real-world systems. To achieve the overall goal, firstly, a genetic algorithm (GA) suitable for analysis of systems with multi-level redundancies is developed. For this GA, new multi-level chromosome, new crossover and mutation operators capable of combining building blocks at different level and mutation of solutions at various levels are designed. Whilst the GA chromosome and regeneration operators are specially designed for handling multi-level systems, in the second step a Non-dominated sorted genetic algorithm (NSGA-II) is developed for multi-dimensional search towards finding Pareto frontier solutions with respect to a number of cost-related, performance-related and reliability-rated objectives including cost, size, weight, availability and failure rate. In the final stage, the developed search and optimisation methods are implemented in a software tool written in MATLAB. Employing the optimisation tool for benchmark problems with multi-level redundancies, heating, ventilation and air conditioning (HVAC) systems, it has been shown how an integrated multi-level redundancy allocation, as opposed to sequential redundancy allocation, can lead to superior solutions.
29

Examining the practice of information literacy teaching and learning in upper secondary schools in Vietnam

Huyen, Ngo Thi January 2017 (has links)
This study aims to investigate the practice of information literacy (IL) teaching and learning in Vietnam’s upper secondary schools. The research employed a mixed-methods multiple case study approach, including three phases of data collection. It started with a paper questionnaire to investigate students’ IL level and their self-assessment of that ability. This was followed by student interviews. The third phase included professional interviews (librarians, teachers, administrators) and an analysis of documents (including educational projects, reports, teachers’ resources and textbooks). An expanded version of the Standards for the 21st-Century Learner (AASL, 2007) which contains four original standards and an additional standard was used as a theoretical framework for the study. A pilot study was conducted at an upper secondary school in Vietnam in order to set up suggestions for the main study. The main study was then carried out in two upper secondary schools. The research indicates that more works need to be done to improve students’ IL, especially information evaluation skill. A number of factors affecting students’ IL were explored, including internal and external factors. Although several reasons were identified to explain the difference of students’ IL scores, the use of technology had no impact on their IL capability. The weakness of students’ IL capability might result from the absence of IL programmes in the schools. The research found that time pressure, teaching method, resource issues and students resulted in the above problem. The study proposed a preliminary IL teaching model for Vietnam’s upper secondary schools. This study has made contributions to both theory and practice. One of the most significant contributions is associated with the study context, because while IL research has been hitherto dominated by English-speaking countries, Vietnam, however, remains underrepresented. Even so, this research remains limitations that need to be addressed in future studies.
30

Behaviours of functionally graded sandwich micro-beams and plates

Trinh, Luan Cong January 2017 (has links)
Functionally graded materials (FGMs) are a novel class of materials having unique characteristics formed of two or more constituent phases with a continuously variable composition. The introduction of these materials to the sandwich structures creates more potentials to the structural applications with the ability of tailoring the material properties as well as the possibility of avoiding the delamination and stress concentration in conventional sandwich structures. With the rapid development of technology, it is now common to use FGMs in micro/nanoelectromechanical systems, e.g. thin films, sensors, actuators and other devices. At these scales, the use of experimentation to understand the structural behaviours is difficult and highly time-consuming, whilst the molecular modelling is computationally very expensive for the scales that are popular to structural engineers. Therefore, higher-order continuum theories, which were developed from the classical continua, become very popular in modelling micro/nano-scale structures. Based on one of these higher-order continuum theories namely the modified couple stress theory, this thesis aims to develop the analytical methods, i.e. Navier and state space based solutions, to analyse the static, free vibration and buckling behaviours of FG and FG-sandwich beams and plates. The governing equations and appropriate boundary conditions are developed for these structural behaviours of beams and plates at both micro and macro- scales using the variational principle. Numerical results are computed using MATLAB and verified with the published results to demonstrate the accuracy and efficiency of the developed theoretical formulation. The numerical applications include: · the free vibration and buckling behaviours of FG and FG sandwich macrobeams under arbitrary boundary conditions and mechanical/thermal loads, · the static, free vibration and buckling behaviours of simply supported FG microbeams, and the free vibration behaviour of bidirectional FG microbeams under arbitrary boundary conditions, · the static, free vibration and buckling behaviours of simply supported FG-sandwich microplates under mechanical/thermal loads, · the static, free vibration and buckling behaviours of FG-sandwich microplates with two opposite simply supported edges and various boundary conditions for other edges. The outcomes from this thesis emphasize the need of including couple stress in analyzing the structural behaviours of FG beams and plates at microscales. Some of them are presented at the first time and can be used as the benchmark results for numerical methods. These analytical methods can also be combined with other strong form methods to analyse various types of complex structures.

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