Surface wave techniques for the study of engineering structures and materials

A wire drive pulse echo method of measuring the spectrum of solid bodies described. Using an 's' plane representation, a general analysis of the transient response of such solids has been carried out. This was used for the study of the stepped amplitude transient of high order modes of disks and for the case where there are two adjacent resonant frequencies. The techniques developed have been applied to the measurenent of the elasticities of refractory materials at high temperatures. In the experimental study of the high order in-plane resonances of thin disks it was found that the energy travelled at the edge of the disk and this initiated the work on one dimensional Rayleigh waves.Their properties were established for the straight edge condition by following an analysis similar to that of the two dimensional case. Experiments were then carried out on the velocity dispersion of various circuits including the disk and a hole in a large plate - the negative curvature condition.Theoretical analysis established the phase and group velocities for these cases and experimental tests on aluminium and glass gave good agreement with theory. At high frequencies all velocities approach that of the one dimensional Rayleigh waves. When applied to crack detection it was observed that a signal burst travelling round a disk showed an anomalous amplitude effect. In certain cases the signal which travelled the greater distance had the greater amplitude.An experiment was designed to investigate the phenanenon and it was established that the energy travelled in two nodes with different velocities.It was found by analysis that as well as the Rayleigh surface wave on the edge, a seoond node travelling at about the shear velocity was excited and the calculated results gave reasonable agreement with the experiments.

Immunological and biochemical techniques in the analysis of tear proteins

This study is concerned with the analysis of tear proteins, paying particular attention to the state of the tears (e.g. non-stimulated, reflex, closed), created during sampling, and to assess their interactions with hydrogel contact lenses. The work has involved the use of a variety of biochemical and immunological analytical techniques for the measurement of proteins, (a), in tears, (b), on the contact lens, and (c), in the eluate of extracted lenses. Although a diverse range of tear components may contribute to contact lens spoilation, proteins were of particular interest in this study because of their theoretical potential for producing immunological reactions. Although normal host proteins in their natural state are generally not treated as dangerous or non-self, those which undergo denaturation or suffer a conformational change may provoke an excessive and unnecessary immune response. A novel on-lens cell based assay has been developed and exploited in order to study the role of the ubiquitous cell adhesion glycoprotein, vitronectin, in tears and contact lens wear under various parameters. Vitronectin, whose levels are known to increase in the closed eye environment and shown here to increase during contact lens wear, is an important immunoregulatory protein and may be a prominent marker of inflammatory activity. Immunodiffusion assays were developed and optimised for use in tear analysis, and in a series of subsequent studies used for example in the measurement of albumin, lactoferrin, IgA and IgG. The immunodiffusion assays were then applied in the estimation of the closed eye environment; an environment which has been described as sustaining a state of sub-clinical inflammation. The role and presence of a lesser understood and investigated protein, kininogen, was also estimated, in particular, in relation to contact lens wear. Difficulties arise when attempting to extract proteins from the contact lens in order to examine the individual nature of the proteins involved. These problems were partly alleviated with the use of the on-lens cell assay and a UV spectrophotometry assay, which can analyse the lens surface and bulk respectively, the latter yielding only total protein values. Various lens extraction methods were investigated to remove protein from the lens and the most efficient was employed in the analysis of lens extracts. Counter immunoelectrophoresis, an immunodiffusion assay, was then applied to the analysis of albumin, lactoferrin, IgA and IgG in the resultant eluates.

Experimental and theoretical studies on a distributed temperature sensor based on Brillouin scattering

Results are reported from recent research on the use of the Brillouin gain/loss mechanism for distributed sensing. A theoretical model of the interaction of the pulsed and CW beams is described and compared with experiments. Results from a system with a 51 km sensing length are presented. We finally investigate issues related to the variation within the sensing fiber of the polarizations of the two beams.

Supporting English language teachers doing further degrees at a distance:a web based strategy researched

This thesis explores how the world-wide-web can be used to support English language teachers doing further studies at a distance. The future of education worldwide is moving towards a requirement that we, as teacher educators, use the latest web technology not as a gambit, but as a viable tool to improve learning. By examining the literature on knowledge, teacher education and web training, a model of teacher knowledge development, along with statements of advice for web developers based upon the model are developed. Next, the applicability and viability of both the model and statements of advice are examined by developing a teacher support site (bttp://www. philseflsupport. com) according to these principles. The data collected from one focus group of users from sixteen different countries, all studying on the same distance Masters programme, is then analysed in depth. The outcomes from the research are threefold: A functioning website that is averaging around 15, 000 hits a month provides a professional contribution. An expanded model of teacher knowledge development that is based upon five theoretical principles that reflect the ever-expanding cyclical nature of teacher learning provides an academic contribution. A series of six statements of advice for developers of teacher support sites. These statements are grounded in the theoretical principles behind the model of teacher knowledge development and incorporate nine keys to effective web facilitation. Taken together, they provide a forward-looking contribution to the praxis of web supported teacher education, and thus to the potential dissemination of the research presented here. The research has succeeded in reducing the proliferation of terminology in teacher knowledge into a succinct model of teacher knowledge development. The model may now be used to further our understanding of how teachers learn and develop as other research builds upon the individual study here. NB: Appendix 4 is only available only available for consultation at Aston University Library with prior arrangement.

Rough-terrain groundspeed measurement:a radar-based commercial solution

Off-highway motive plant equipment is costly in capital outlay and maintenance. To reduce these overheads and increase site safety and workrate, a technique of assessing and limiting the velocity of such equipment is required. Due to the extreme environmental conditions met on such sites, conventional velocity measurement techniques are inappropriate. Ogden Electronics Limited were formed specifically to manufacture a motive plant safety system incorporating a speed sensor and sanction unit; to date, the only such commercial unit available. However, problems plague the reliability, accuracy and mass production of this unit. This project assesses the company's exisiting product, and in conjunction with an appreciation of the company history and structure, concludes that this unit is unsuited to its intended application. Means of improving the measurement accuracy and longevity of this unit, commensurate with the company's limited resources and experience, are proposed, both for immediate retrofit and for longer term use. This information is presented in the form of a number of internal reports for the company. The off-highway environment is examined; and in conjunction with an evaluation of means of obtaining a returned signal, comparisons of processing techniques, and on-site gathering of previously unavailable data, preliminary designs for an alternative product are drafted. Theoretical aspects are covered by a literature review of ground-pointing radar, vehicular radar, and velocity measuring systems. This review establishes and collates the body of knowledge in areas previously considered unrelated. Based upon this work, a new design is proposed which is suitable for incorporation into the existing company product range. Following production engineering of the design, five units were constructed, tested and evaluated on-site. After extended field trials, this design has shown itself to possess greater accuracy, reliability and versatility than the existing sensor, at a lower unit cost.

User interface design support for the development of knowledge-based systems

The present scarcity of operational knowledge-based systems (KBS) has been attributed, in part, to an inadequate consideration shown to user interface design during development. From a human factors perspective the problem has stemmed from an overall lack of user-centred design principles. Consequently the integration of human factors principles and techniques is seen as a necessary and important precursor to ensuring the implementation of KBS which are useful to, and usable by, the end-users for whom they are intended. Focussing upon KBS work taking place within commercial and industrial environments, this research set out to assess both the extent to which human factors support was presently being utilised within development, and the future path for human factors integration. The assessment consisted of interviews conducted with a number of commercial and industrial organisations involved in KBS development; and a set of three detailed case studies of individual KBS projects. Two of the studies were carried out within a collaborative Alvey project, involving the Interdisciplinary Higher Degrees Scheme (IHD) at the University of Aston in Birmingham, BIS Applied Systems Ltd (BIS), and the British Steel Corporation. This project, which had provided the initial basis and funding for the research, was concerned with the application of KBS to the design of commercial data processing (DP) systems. The third study stemmed from involvement on a KBS project being carried out by the Technology Division of the Trustees Saving Bank Group plc. The preliminary research highlighted poor human factors integration. In particular, there was a lack of early consideration of end-user requirements definition and user-centred evaluation. Instead concentration was given to the construction of the knowledge base and prototype evaluation with the expert(s). In response to this identified problem, a set of methods was developed that was aimed at encouraging developers to consider user interface requirements early on in a project. These methods were then applied in the two further projects, and their uptake within the overall development process was monitored. Experience from the two studies demonstrated that early consideration of user interface requirements was both feasible, and instructive for guiding future development work. In particular, it was shown a user interface prototype could be used as a basis for capturing requirements at the functional (task) level, and at the interface dialogue level. Extrapolating from this experience, a KBS life-cycle model is proposed which incorporates user interface design (and within that, user evaluation) as a largely parallel, rather than subsequent, activity to knowledge base construction. Further to this, there is a discussion of several key elements which can be seen as inhibiting the integration of human factors within KBS development. These elements stem from characteristics of present KBS development practice; from constraints within the commercial and industrial development environments; and from the state of existing human factors support.

Modelling human performance within manufacturing systems design:from a theoretical towards a practical framework

Computer-based simulation is frequently used to evaluate the capabilities of proposed manufacturing system designs. Unfortunately, the real systems are often found to perform quite differently from simulation predictions and one possible reason for this is an over-simplistic representation of workers' behaviour within current simulation techniques. The accuracy of design predictions could be improved through a modelling tool that integrates with computer-based simulation and incorporates the factors and relationships that determine workers' performance. This paper explores the viability of developing a similar tool based on our previously published theoretical modelling framework. It focuses on evolving this purely theoretical framework towards a practical modelling tool that can actually be used to expand the capabilities of current simulation techniques. Based on an industrial study, the paper investigates how the theoretical framework works in practice, analyses strengths and weaknesses in its formulation, and proposes developments that can contribute towards enabling human performance modelling in a practical way.

Antecedents of strategic flexibility:management cognition, firm resources and strategic options

Purpose: Current conceptualisations of strategic flexibility and its antecedents are theory-driven, which has resulted in a lack of consensus. To summarise this domain the paper aims to develop and present an a priori conceptual model of the antecedents and outcomes of strategic flexibility. Discussion and insights into the conceptual model, and the relationships specified, are made through a novel qualitative empirical approach. The implications for further research and a framework for further theoretical development are presented. Design/methodology/approach: An exploratory qualitative research design is used applying multiple data collection techniques in a branch network of a large regional retailer in the UK. The development of strategic options and the complex relationship to strategic flexibility is investigated. Findings: The number and type of strategic options developed by managers impact on the degree of strategic flexibility and also on the ability of the firm to achieve competitive differentiation. Additionally, the type of strategic option implemented by managers is dependent on the competitive situation faced at a local level. Evidence of managers' limited perception of competition was identified based on their spatial embeddedness. Research limitations/implications: A single, in-depth case study was used. The data gathered is rich and appropriate for the exploratory approach adopted here. However, generalisability of the findings is limited. Practical implications: Strategic flexibility is rooted in the ability of front-line mangers to develop and implement strategic options; this in turn facilitates competitive differentiation. Originality/value: The research presented is unique in this domain on two accounts. First, theory is developed by presenting an a priori conceptual model, and testing through in-depth qualitative data gathering. Second, insights into strategic flexibility are presented through an examination of managerial cognition, resources and strategic option generation using cognitive mapping and laddering technique. © Emerald Group Publishing Limited.

Developing a complex intervention to reduce time to presentation with symptoms of lung cancer

Background - Lung cancer is the commonest cause of cancer in Scotland and is usually advanced at diagnosis. Median time between symptom onset and consultation is 14 weeks, so an intervention to prompt earlier presentation could support earlier diagnosis and enable curative treatment in more cases. Aim - To develop and optimise an intervention to reduce the time between onset and first consultation with symptoms that might indicate lung cancer. Design and setting - Iterative development of complex healthcare intervention according to the MRC Framework conducted in Northeast Scotland. Method - The study produced a complex intervention to promote early presentation of lung cancer symptoms. An expert multidisciplinary group developed the first draft of the intervention based on theory and existing evidence. This was refined following focus groups with health professionals and high-risk patients. Results - First draft intervention components included: information communicated persuasively, demonstrations of early consultation and its benefits, behaviour change techniques, and involvement of spouses/partners. Focus groups identified patient engagement, achieving behavioural change, and conflict at the patient–general practice interface as challenges and measures were incorporated to tackle these. Final intervention delivery included a detailed self-help manual and extended consultation with a trained research nurse at which specific action plans were devised. Conclusion -The study has developed an intervention that appeals to patients and health professionals and has theoretical potential for benefit. Now it requires evaluation.

Competitive edge through operations management

A view has emerged within manufacturing and service organizations that the operations management function can hold the key to achieving competitive edge. This has recently been emphasized by the demands for greater variety and higher quality which must be set against a background of increasing cost of resources. As nations' trade barriers are progressively lowered and removed, so producers of goods and service products are becoming more exposed to competition that may come from virtually anywhere around the world. To simply survive in this climate many organizations have found it necessary to improve their manufacturing or service delivery systems. To become real ''winners'' some have adopted a strategic approach to operations and completely reviewed and restructured their approach to production system design and operations planning and control. The articles in this issue of the International journal of Operations & Production Management have been selected to illustrate current thinking and practice in relation to this situation. They are all based on papers presented to the Sixth International Conference of the Operations Management Association-UK which was held at Aston University in June 1991. The theme of the conference was "Achieving Competitive Edge" and authors from 15 countries around the world contributed to more than 80 presented papers. Within this special issue five topic areas are addressed with two articles relating to each. The topics are: strategic management of operations; managing change; production system design; production control; and service operations. Under strategic management of operations De Toni, Filippini and Forza propose a conceptual model which considers the performance of an operating system as a source of competitive advantage through the ''operation value chain'' of design, purchasing, production and distribution. Their model is set within the context of the tendency towards globalization. New's article is somewhat in contrast to the more fashionable literature on operations strategy. It challenges the validity of the current idea of ''world-class manufacturing'' and, instead, urges a reconsideration of the view that strategic ''trade-offs'' are necessary to achieve a competitive edge. The importance of managing change has for some time been recognized within the field of organization studies but its relevance in operations management is now being realized. Berger considers the use of "organization design", ''sociotechnical systems'' and change strategies and contrasts these with the more recent idea of the ''dialogue perspective''. A tentative model is suggested to improve the analysis of different strategies in a situation specific context. Neely and Wilson look at an essential prerequisite if change is to be effected in an efficient way, namely product goal congruence. Using a case study as its basis, their article suggests a method of measuring goal congruence as a means of identifying the extent to which key performance criteria relating to quality, time, cost and flexibility are understood within an organization. The two articles on production systems design represent important contributions to the debate on flexible production organization and autonomous group working. Rosander uses the results from cases to test the applicability of ''flow groups'' as the optimal way of organizing batch production. Schuring also examines cases to determine the reasons behind the adoption of ''autonomous work groups'' in The Netherlands and Sweden. Both these contributions help to provide a greater understanding of the production philosophies which have emerged as alternatives to more conventional systems -------for intermittent and continuous production. The production control articles are both concerned with the concepts of ''push'' and ''pull'' which are the two broad approaches to material planning and control. Hirakawa, Hoshino and Katayama have developed a hybrid model, suitable for multistage manufacturing processes, which combines the benefits of both systems. They discuss the theoretical arguments in support of the system and illustrate its performance with numerical studies. Slack and Correa's concern is with the flexibility characteristics of push and pull material planning and control systems. They use the case of two plants using the different systems to compare their performance within a number of predefined flexibility types. The two final contributions on service operations are complementary. The article by Voss really relates to manufacturing but examines the application of service industry concepts within the UK manufacturing sector. His studies in a number of companies support the idea of the ''service factory'' and offer a new perspective for manufacturing. Harvey's contribution by contrast, is concerned with the application of operations management principles in the delivery of professional services. Using the case of social-service provision in Canada, it demonstrates how concepts such as ''just-in-time'' can be used to improve service performance. The ten articles in this special issue of the journal address a wide range of issues and situations. Their common aspect is that, together, they demonstrate the extent to which competitiveness can be improved via the application of operations management concepts and techniques.

Multiple criteria decision-making techniques in higher education

Purpose: The purpose of this paper is to review the literature which focuses on four major higher education decision problems. These are: resource allocation; performance measurement; budgeting; and scheduling. Design/methodology/approach: Related articles appearing in the international journals from 1996 to 2005 are gathered and analyzed so that the following three questions can be answered: "What kind of decision problems were paid most attention to?"; "Were the multiple criteria decision-making techniques prevalently adopted?"; and "What are the inadequacies of these approaches?" Findings: Based on the inadequacies, some improvements and possible future work are recommended, and a comprehensive resource allocation model is developed taking account of these factors. Finally, a new knowledge-based goal programming technique which integrates some operations of analytic hierarchy process is proposed to tackle the model intelligently. Originality/value: Higher education has faced the problem of budget cuts or constrained budgets for the past 30 years. Managing the process of the higher education system is, therefore, a crucial and urgent task for the decision makers of universities in order to improve their performance or competitiveness. © Emerald Group Publishing Limited.

Synthesis, characterisation and applications of diamond materials

This thesis presented a detailed research work on diamond materials. Chapter 1 is an overall introduction of the thesis. In the Chapter 2, the literature review on the physical, chemical, optical, mechanical, as well as other properties of diamond materials are summarised. Followed by this chapter, several advanced diamond growth and characterisation techniques used in experimental work are also introduced. Then, the successful installation and applications of chemical vapour deposition system was demonstrated in Chapter 4. Diamond growth on a variety of different substrates has been investigated such as on silicon, diamond-like carbon or silica fibres. In Chapter 5, the single crystalline diamond substrate was used as the substrate to perform femtosecond laser inscription. The results proved the potentially feasibility of this technique, which could be utilised in fabricating future biochemistry microfluidic channels on diamond substrates. In Chapter 6, the hydrogen-terminated nanodiamond powder was studied using impedance spectroscopy. Its intrinsic electrical properties and its thermal stability were presented and analysed in details. As the first PhD student within Nanoscience Research Group at Aston, my initial research work was focused on the installation and testing of the microwave plasma enhanced chemical vapour deposition system (MPECVD), which will be beneficial to all the future researchers in the group. The fundamental of the on MPECVD system will be introduced in details. After optimisation of the growth parameters, the uniform diamond deposition has been achieved with a good surface coverage and uniformity. Furthermore, one of the most significant contributions of this work is the successful pattern inscription on diamond substrates by femtosecond laser system. Previous research of femtosecond laser inscription on diamond was simple lines or dots, with little characterisation techniques were used. In my research work, the femtosecond laser has been successfully used to inscribe patterns on diamond substrate and fully characterisation techniques, e.g. by SEM, Raman, XPS, as well as AFM, have been carried out. After the femtosecond laser inscription, the depth of microfluidic channels on diamond film has been found to be 300~400 nm, with a graphitic layer thickness of 165~190 nm. Another important outcome of this work is the first time to characterise the electrical properties of hydrogenterminated nanodiamond with impedance spectroscopy. Based on the experimental evaluation and mathematic fitting, the resistance of hydrogen-terminated nanodiamond reduced to 0.25 MO, which were four orders of magnitude lower than untreated nanodiamond. Meanwhile, a theoretical equivalent circuit has been proposed to fit the results. Furthermore, the hydrogenterminated nanodiamond samples were annealed at different temperature to study its thermal stability. The XPS and FTIR results indicate that hydrogen-terminated nanodiamond will start to oxidize over 100ºC and the C-H bonds can survive up to 400ºC. This research work reports the fundamental electrical properties of hydrogen-terminated nanodiamond, which can be used in future applications in physical or chemical area.

The introduction of group technology via coding techniques:a case study

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