22 resultados para empirical studies in interaction design

em Aston University Research Archive


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Much has been written about the potential impact of Lean Agile paradigm on firm's supply chain performance. However, most of the existing studies mainly pointed out Lean is for cost reduction, whereas Agility is for attaining flexibility. There are little empirical studies in literature that examined how Lean Agile paradigm impacts on supply chain performance. This paper aims to address this gap by studying the influence of Lean and Agility paradigms on a single commodity supply chain delivery performance in the aerospace industry. Data was collected from four separate 'Rigid pipes' supply chains to study how manufacturing alignment impacts on the delivery performance. Implications of the study to practitioners and academia are discussed and future research outlined.

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The purpose of this thesis is to conduct empirical research in corporate Thailand in order to (1) validate the Spirit at Work Scale (2) investigate the relationships between individual spirit at work and three employee work attitudinal variables (job satisfaction, organisational identification and psychological well-being) and three organisational outcomes (in-role performance, organisational citizenship behaviours (OCB), and turnover intentions) (3) further examine causal relations among these organisational behaviour variables with a longitudinal design (4) examine three employee work attitudes as mediator variables between individual spirit at work and three organisational outcomes and (5) explore the potential antecedents of organisational conditions that foster employee experienced individual spirit at work. The two pilot studies with 155 UK and 175, 715 Thai samples were conducted for validation testing of the main measure used in this study: Spirit at Work Scale (Kinjerski & Skrypnek, 2006a). The results of the two studies including discriminant validity analyses strongly provided supportive evidence that Spirit at Work Scale (SAWS) is a sound psychometric measure and also a distinct construct from the three work attitude constructs. The final model of SAWS contains a total of twelve items; a three factor structure (meaning in work, sense of community, and spiritual connection) in which the sub-factors loaded on higher order factors and also had very acceptable reliability. In line with these results it was decided to use the second-order of SAWS model for Thai samples in the main study and subsequent analysis. The 715 completed questionnaires were received from the first wave of data collection during July - August 2008 and the second wave was conducted again within the same organisations and 501 completed questionnaires were received during March - April 2009. Data were obtained through 49 organisations which were from three types of organisations within Thailand: public organisations, for-profit organisations, and notfor-profit organisations. Confirmatory factor analysis of all measures used in the study and hypothesised model were tested with structural equation modelling techniques. The results were greatly supportive for the direct structural model and partially supportive for the fully mediated model. Moreover, there were different findings across self report and supervisor rating on performance and OCB models. Additionally, the antecedent conditions that fostered employees experienced individual spirit at work and the implications of these findings for research and practice are discussed.

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This thesis is a theoretical study of the accuracy and usability of models that attempt to represent the environmental control system of buildings in order to improve environmental design. These models have evolved from crude representations of a building and its environment through to an accurate representation of the dynamic characteristics of the environmental stimuli on buildings. Each generation of models has had its own particular influence on built form. This thesis analyses the theory, structure and data of such models in terms of their accuracy of simulation and therefore their validity in influencing built form. The models are also analysed in terms of their compatability with the design process and hence their ability to aid designers. The conclusions are that such models are unlikely to improve environmental performance since: a the models can only be applied to a limited number of building types, b they can only be applied to a restricted number of the characteristics of a design, c they can only be employed after many major environmental decisions have been made, d the data used in models is inadequate and unrepresentative, e models do not account for occupant interaction in environmental control. It is argued that further improvements in the accuracy of simulation of environmental control will not significantly improve environmental design. This is based on the premise that strategic environmental decisions are made at the conceptual stages of design whereas models influence the detailed stages of design. It is hypothesised that if models are to improve environmental design it must be through the analysis of building typologies which provides a method of feedback between models and the conceptual stages of design. Field studies are presented to describe a method by which typologies can be analysed and a theoretical framework is described which provides a basis for further research into the implications of the morphology of buildings on environmental design.

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This article characterizes key weaknesses in the ability of current digital libraries to support scholarly inquiry, and as a way to address these, proposes computational services grounded in semiformal models of the naturalistic argumentation commonly found in research literatures. It is argued that a design priority is to balance formal expressiveness with usability, making it critical to coevolve the modeling scheme with appropriate user interfaces for argument construction and analysis. We specify the requirements for an argument modeling scheme for use by untrained researchers and describe the resulting ontology, contrasting it with other domain modeling and semantic web approaches, before discussing passive and intelligent user interfaces designed to support analysts in the construction, navigation, and analysis of scholarly argument structures in a Web-based environment. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 17–47, 2007.

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The thesis aims to provide empirical studies towards Chinese corporate governance. Since China initially established its stock exchange system in the 1990s, it has gone through different stages of changes to become a more market-oriented system. Extensive studies have been conducted in Chinese corporate governance, however, many were theoretical discussion focusing on the early stages and there‘s a general lack of empirical analysis. This paper provides three empirical analysis of the Chinese corporate governance: the overall market discipline efficiency, the impact of capital structure on agency costs, the status of 2005- 2006 reform that substantially modified ownership structure of Chinese listed firms and separated ownership and control of listed firms. The three empirical studies were selected to reflect four key issues that need answering: the first empirical study, using event study to detect market discipline on a collective level. This study filled a gap in the Chinese stock market literature for being the first one ever using cross-market data to test market discipline. The second empirical study endeavoured to contribute to the existing corporate governance literature regarding capital structure and agency costs. Two conclusions can be made through this study: 1) for Chinese listed firms, higher gearing means higher asset turnover ratios and ROE, i.e. more debts seem to reduce agency costs; 2) concentration level of shares appears to be irrelevant with company performance, controlling shareholders didn‘t seem to commit to the improvement of corporate assets utilization or contribute to reducing agency costs. This study addressed a key issue in Chinese corporate governance since the state has significant shareholding in most big listed companies. The discussion of corporate governance in the Chinese context would be completely meaningless without discussing the state‘s role in corporate governance, given that about 2/3 of the almost all shares were non-circulating shares controlled by the state before the 2005-2006 overhaul ownership reform. The third study focused on the 2005-2006 reform of ownership of Chinese listed firms. By collecting large-scale data covering all 64 groups of Chinese listed companies went through the reform by the end of 2006 (accounting for about 97.86% and 96.76% of the total market value of Shanghai (SSE) and Shenzhen Stock Exchange (SZSE) respectively), a comprehensive study about the ownership reform was conducted. This would be first and most comprehensive empirical study in this area. The study of separated ownership and control of listed firm is the first study conducted using the ultimate ownership concept in Chinese context.

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This book presents current research on boundary spanning elements. The editors bring together extant knowledge in the field and present a uniform narrative. Previous studies have often been disseminated across several academic disciplines like services marketing, personal selling and sales management etc. and this monograph aggregates studies dealing with boundary spanning elements or has boundary spanning elements related to the marketing function as the main empirical platform under a uniform theoretical perspective. Each chapter in the book deals with an important research theme and synthesizes studies in relation to boundary spanning elements.

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Purpose – This paper aims to apply the business-to-business (B2B) Service Brand Identity (SBI) scale to empirically assess the influence of service brand identity on brand performance for the first time. Design/methodology/approach – Based on data collected from 421 senior marketing executives, this paper applies the B2B SBI and structural equation modeling to fulfill the above purpose. Findings – Brand personality and human resource initiatives have a positive and significant influence on brand performance. Corporate visual identity, in addition to an employee and client focus, has an insignificant impact on performance. Consistent communications have a negative and significant influence on brand performance. Research limitations/implications – Data were only collected from executives in the UK. This research would benefit from replicative studies. Practical implications – This research empirically establishes the brand management activities that drive brand performance. Originality/value – This is the first empirical study to assess the influence service brand identity has on brand performance.

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A cross-sectional study aims to describe the overall picture of a phenomenon, a situational problem, an attitude or an issue, by asking a cross-section of a given population at one specified moment in time. This paper describes the key features of the cross-sectional survey method. It begins by highlighting the main principles of the method, then discusses stages in the research process, drawing on two surveys of primary care pharmacists to illustrate some salient points about planning, sampling frames, definition and conceptual issues, research instrument design and response rates. Four constraints in prescribing studies were noted. First the newness of the subject meant a low basis of existing knowledge to design a questionnaire. Second, there was no public existing database for the sampling frame, so a pragmatic sampling exercise was used. Third, the definition of a Primary Care Pharmacist (PCP) [in full] and respondents recognition of that name and identification with the new role limited the response. Fourth, a growing problem for all surveys, but particularly with pharmacists and general practitioners (GP) [in full] is the growing danger of survey fatigue, which has a negative impact on response levels.

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The primary theme of this research was the characterisation of new and novel organo-tellurium complexes, using the technique of single crystal X-ray analysis to establish more firmly the various coordination modes of tellurium. In each study the unit cell dimensions and intensity data were collected using an Enraf-Nonius CAD-4, four circle diffractometer. The raw data collected in turn was transferred to the Birmingham University Honeywell Multics System and processed using the appropriate computer packages for the determination of crystal structures. The molecular and crystal structures of: bis[2-(2-pyridyl)phenyl]tritelluride, bis[2-(N-hydroxy)iminophenyl] ditelluride, 2-(2-pyridyl)phenyltellurium(IV) tribromide, (2-N,N-dimethylbenzylamine-C,N')tellurium(IV)tribromide, 2-dichloro(butyl)tellurobenzaldehyde, 2-dichlorobutotelluro-N-dimethylbenzyl ammonium chloride, dimethyldithiocarbamato[2-(2-pyridyl)phenyl]tellurium(II), dimethyldithiocarbamato[2-(2-quinolinyl)phenyl]tellurium(II) and para-ethoxypheny[2-(2-pyridyl)phenyl]telluride are described. In each structure, the Lewis acidity of tellurium appears to be satisfied by autocomplex formation, through short-range intramolecular secondary bonds between tellurium and an electron denoting species, (generally nitrogen in these structures) with long range weak inter molecular contacts forming in the majority of the tellurium(IV) structures. The order of Lewis acidity in each structure can be considered to be reflected by the length of the short range intramolecular secondary bond, identified, that is, when tellurium has a low Lewis acidity this interaction is long. Interestingly, no primary bonds are found trans to a Te-C covalent bond in any of the above structures, highlighting the strong trans effect of aromatic and aryl groups in tellurium complexes.

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Perturbations in the bismuth market resulted in Mining and Chemical Products Ltd., seeking further outlets in the market. Together with Manchem Ltd. they were anxious to evaluate the possibility of using bismuth compounds as a replacement for lead/calcium soaps in paint driers. A range of new organobismuth compounds were synthesised of the type RBiX2 and R3BiX2 (X= halogen, OOCR, dithiocarbamate). A variety of synthetic techniques were explored, including the use of mathematical reactions, phase-transfer catalysis and microwave energy. The preparation of a range of trivalent and pentavalent organobismuth carboxylates is reported and their infra-red , 13C, lH nmr spectra. The compounds were evaluated as paint driers and in cases found to enhance paint drying to a greater degree than the standard driers, to which they were being compared. The drying times of paint films containing the organobismuth compounds are reported, together with a comparison of the drying times with the addition of bismuth tris-diethyldithiocarbamate, which may promote the cross-linking reaction that occur in paint films during the drying process. Examples are reported to illustrate the great reductions in reaction times possible when using microwave energy. Reactions such as metallation of aromatic rings, ligand redistribution and synthesis were carried out in PTFE containers in a conventional domestic microwave oven. An X-ray diffraction study of (phenylazophenyl-C,N')mercury(II) chloride has shown it to be dimeric via long Hg-Cl bridging interactions of 3.367A. Its crystal structure is reported, together with its 13C nmr spectra and mass spectrum. The Lewis acidity of compounds of the type RBiX2 was investigated. The donor group being anchored to the organo group (R). The dithiocarbamates bis- (diethyldithiobarbamato)phenylbismuth(Ill) and [2-2-pyridyl)phenylbismuth(III) were synthesised, and their crystal structures, 14N, 13C nmr ar1d infra-red spectra are reported. Both compounds are pseudo-pentagonal bipyramidal in geometry, with two long Bi-S bonds and two short Bi-S bonds. The reaction of RBiBr2 (R= 2-(pyridyl) with various ligands is reported. The infra-red evidence suggesting that the coordination of extra ligands is accompanied by a reduction of the strength of the Bi-interaction.

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The work is a logical continuation of research started at Aston some years ago when studies were conducted on fermentations in bubble columns. The present work highlights typical design and operating problems that could arise in such systems as waste water, chemical, biochemical and petroleum operations involving three-phase, gas-liquid-solid fluidisation; such systems are in increasing use. It is believed that this is one of few studies concerned with `true' three-phase, gas-liquid-solid fluidised systems, and that this work will contribute significantly to closing some of the gaps in knowledge in this area. The research work was mainly experimentally based and involved studies of the hydrodynamic parameters, phase holdups (gas and solid), particle mixing and segregation, and phase flow dynamics (flow regime and circulation patterns). The studies have focused particularly on the solid behaviour and the influence of properties of solids present on the above parameters in three-phase, gas-liquid-solid fluidised systems containing single particle components and those containing binary and ternary mixtures of particles. All particles were near spherical in shape and two particle sizes and total concentration levels were used. Experiments were carried out in two- and three-dimensional bubble columns. Quantitative results are presented in graphical form and are supported by qualitative results from visual studies which are also shown as schematic diagrams and in photographic form. Gas and solid holdup results are compared for air-water containing single, binary and ternary component particle mixtures. It should be noted that the criteria for selection of the materials used are very important if true three-phase fluidisation is to be achieved: this is very evident when comparing the results with those in the literature. The fluid flow and circulation patterns observed were assessed for validation of the generally accepted patterns, and the author believes that the present work provides more accurate insight into the modelling of liquid circulation in bubble columns. The characteristic bubbly flow at low gas velocity in a two-phase system is suppressed in the three-phase system. The degree of mixing within the system is found to be dependent on flow regime, liquid circulation and the ratio of solid phase physical properties. Evidence of strong `trade-off' of properties is shown; the overall solid holdup is believed to be a major parameter influencing the gas holdup structure.

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The study of surfactant monolayers is certainly not a new technique, but the application of monolayer studies to elucidate controlling factors in liposome design remains an underutilised resource. Using a Langmuir-Blodgett trough, pure and mixed lipid monolayers can be investigated, both for their interactions within the monolayer, and for interfacial interactions with drugs in the aqueous sub-phase. Despite these monolayers effectively being only half a bilayer, with a flat rather than curved structure, information from these studies can be effectively translated into liposomal systems. Here we outline the background, general protocols and application of Langmuir studies with a focus on their application in liposomal systems. A range of case studies are discussed which show how the system can be used to support its application in the development of liposome drug delivery. Examples include investigations into the effect of cholesterol within the liposome bilayer, understanding effective lipid packaging within the bilayer to promote water soluble and poorly soluble drug retention, the effect of alkyl chain length on lipid packaging, and drug-monolayer electrostatic interactions that promote bilayer repackaging.

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This thesis is concerned with the means by which the state in Britain has attempted to influence the technological development of private industry in the period 1945-1979. Particular emphasis is laid on assessing the abilities of technology policy measures to promote innovation. With that objective, the innovation literature is selectively reviewed to draw up an analytical framework to evaluate the innovation content of policy (Chapter 2). Technology policy is taken to consist of the specific measures utilised by government and its agents that affect the technological behaviour of firms. The broad sweep of policy during the period under consideration is described in Chapter 3 which concentrates on elucidating its institutional structure and the activities of the bodies involved. The empirical core of the thesis consists of three parallel case studies of policy toward the computer, machine tool and textile machinery industries (Chapters 4-6). The studies provide detailed historical accounts of the development and composition of policy, relating it to its specific institutional and industrial contexts. Each reveals a different pattern and level of state intervention. The thesis concludes with a comparative review of the findings of the case studies within a discussion centred on the arguments presented in Chapter 2. Topics arising include the state's differential support for the range of activities involved in innovation, the location of state-funded R&D, the encouragement of supplier-user contact, and the difficulties raised in adoption and diffusion.