827 resultados para ways of seeing
Resumo:
Musculoskeletal diseases are one of the major causes of disability around the world and have been a significant reason for the development of the Bone and Joint Decade. Rheumatoid arthritis, osteoarthritis and back pain are important causes of disability-adjusted-life years in both the developed and developing world. COPCORD studies in over 17 countries around the world have identified back and knee pain as common in the community and are likely to increase with the ageing population. Musculoskeletal conditions are an enormous cost to the community in economic terms, and these figures emphasise how governments need to invest in the future and look at ways of reducing the burden of musculoskeletal diseases by encouraging exercise and obesity prevention campaigns.
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Successful, long-term implementation of Integrated Pest Management (IPM) requires the integration of key technical and management activities and the participation of a wide range of stakeholders including farmers, researchers, extension officers, crop consultants, government agencies, and industry. A key issue that needs urgent attention is how to achieve the high quality interaction between these different groups which is necessary for sustained IPM. Problem specification and planning workshops (PSPWs) provide one means of facilitating an integrated strategy for tackling complex pest management issues. Since 1992, the Cooperative Research Centre for Tropical Pest Management has facilitated over 20 PSPWs, focusing on different farming systems in Australia. This paper describes the philosophy, the process involved, and the impact that these PSPWs have had. It examines three specific cases to describe the relationship between plans and results and ways of improving impact. The results reinforce the major role that social scientists can play in providing mechanisms for collaborating with technical researchers and other partners to facilitate effective, participatory ventures in IPM.
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Greatly increased competition in the professional services and marketing sectors has reinforced the need for firms to develop an organisational culture that facilitates adaptation to changing conditions and competitive threats. More generally, competitive changes within business environments require new and creative ways of organising and managing firms. In order for marketing practitioners to be ahead of competitors in identifying and meeting customer needs, creative thought is essential. An organisational culture that supports creativity and facilitates the adoption of innovative practices, products and services, improves a firm’s ability to remain competitive within an uncertain environment. This paper presents a conceptual model of an organisational culture supporting creativity and innovation. The model posits relationships between creativity and innovation and organisational performance. The main contribution of the paper is to build a foundation for future research directed primarily towards exploring the relationships in the theoretical model of interest. Implications for marketing practitioners are also considered.
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Sustainable design education is vital for engineering students. This is to allow them to meet the challenges both engineering and the wider community will face in the future. This need has not only been mandated by Engineers Australia’s graduate attributes from an Australian perspective, but more widely the issue of sustainability is one of the greatest challenges humanity has ever faced. Engineers need to be at the forefront of this challenge, because we can not only do the greatest good, but have the potential to cause the greatest harm. The biggest question with respect to the education of engineers about sustainable design is what do engineers need to know, and how best to enable this learning. This paper argues that since the entire phenomenon of sustainable design is constantly growing and changing, it is only by looking at practitioners currently trying design sustainably, and their ways of experiencing sustainable design, can we hope to articulate what it is, and therefore what and how we need to teach engineering students. It also argues that to accommodate sustainable design within engineering, we need to go further and transform the engineering profession to enable it to meet the challenges that sustainability presents. © 2005, Australasian Association for Engineering Education
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The concept of communities of practice (CoPs) has rapidly gained ground in fields such as knowledge management and organisational learning since it was first identified by Lave and Wenger (1991) and Brown and Duguid (1991). In this article, we consider a related concept that we have entitled “communities of implementation.” Communities of implementation (CoIs) are similar to communities of practice in that they offer an opportunity for a collection of individuals to support each other and share knowledge in a dynamic environment and on a topic in which they share interest. In addition, and to differentiate them from CoPs, a community of implementation extends the responsibilities of a CoP by having as its focus the implementation of a programme of change. This may well extend to designing the change programme. Thus, whereas a main purpose of a CoP is to satisfy “a real need to know what each other knows” (Skyrme, 1999) in an informal way, we argue that a main purpose of a community of implementation is to “pool individual knowledge (including contacts and ways of getting things done) to stimulate collective enthusiasm in order to take more informed purposeful action for which the members are responsible.” Individual and collective responsibility and accountability for successfully implementing the actions/change programme is a key feature of a community of implementation. Without these pressures the members might lower the priority of implementation, allowing competing priorities to dominate their attention and resources. Without responsibility and accountability, the result is likely to be (at best) an organisation which has not begun a change programme, or (at worst) an organisation which is stuck halfway through another failing initiative. To achieve these additional objectives beyond those of a CoP, the CoI needs to provide heightened support to its members. In fact often the members will collectively strategise the development and implementation of the change programme they are leading in the organisation. Other concepts similar to CoPs have appeared in the literature, for example “communities of knowing” (Boland & Tenkasi, 1995), but none have a specific focus on implementation. Perhaps the closest example of a CoI, as suggested by our definition, is reported by Karsten, Lyytinen, Hurskainen, and Koskelainen (2001) who describe a CoP in a paper machinery manufacturer which seems to have the necessary focus on implementation. The theoretical aspects of this article will explore the relationship between CoPs and CoIs, and the needs for different arrangements for a CoI. The practical aspect of this article will consist of a report on a case study of a CoI that was successful in its implementation of a programme of change that aimed to improve its organisation’s knowledge management activities. Over two years the CoI implemented a suite of complementary actions across the organisation. These actions transformed the organisation and moved it towards achieving its ‘core values’ and overall objectives. The article will explore: the activities that formed and gelled the community, the role of the community in the implementation of actions, and experiences from key members of this community on its success and potential improvements.
Resumo:
New postgraduate students embark on their research journey typically with little or no experience in doing research. Supervisors and other more experienced student researchers might help them to find their feet during the first few weeks of their research by sharing their own experience of how they solved similar problems during their research. In this way each novice researcher can learn and benefit from other researchers´ ways of resolving problems. This paper discusses the real concerns that researchers reflected upon during a two-day research workshop, where researchers share problems, exchange ideas for overcoming them and learn from each other´s experiences of conducting research. The output from the workshop is in the form of hints and tips that can guide novice researchers when faced with initial problems. The paper can also be used by a department to induct a novice researcher into their environment.
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Queueing theory is an effective tool in the analysis of canputer camrunication systems. Many results in queueing analysis have teen derived in the form of Laplace and z-transform expressions. Accurate inversion of these transforms is very important in the study of computer systems, but the inversion is very often difficult. In this thesis, methods for solving some of these queueing problems, by use of digital signal processing techniques, are presented. The z-transform of the queue length distribution for the Mj GY jl system is derived. Two numerical methods for the inversion of the transfom, together with the standard numerical technique for solving transforms with multiple queue-state dependence, are presented. Bilinear and Poisson transform sequences are presented as useful ways of representing continuous-time functions in numerical computations.
Resumo:
Distributed digital control systems provide alternatives to conventional, centralised digital control systems. Typically, a modern distributed control system will comprise a multi-processor or network of processors, a communications network, an associated set of sensors and actuators, and the systems and applications software. This thesis addresses the problem of how to design robust decentralised control systems, such as those used to control event-driven, real-time processes in time-critical environments. Emphasis is placed on studying the dynamical behaviour of a system and identifying ways of partitioning the system so that it may be controlled in a distributed manner. A structural partitioning technique is adopted which makes use of natural physical sub-processes in the system, which are then mapped into the software processes to control the system. However, communications are required between the processes because of the disjoint nature of the distributed (i.e. partitioned) state of the physical system. The structural partitioning technique, and recent developments in the theory of potential controllability and observability of a system, are the basis for the design of controllers. In particular, the method is used to derive a decentralised estimate of the state vector for a continuous-time system. The work is also extended to derive a distributed estimate for a discrete-time system. Emphasis is also given to the role of communications in the distributed control of processes and to the partitioning technique necessary to design distributed and decentralised systems with resilient structures. A method is presented for the systematic identification of necessary communications for distributed control. It is also shwon that the structural partitions can be used directly in the design of software fault tolerant concurrent controllers. In particular, the structural partition can be used to identify the boundary of the conversation which can be used to protect a specific part of the system. In addition, for certain classes of system, the partitions can be used to identify processes which may be dynamically reconfigured in the event of a fault. These methods should be of use in the design of robust distributed systems.
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Perception of Mach bands may be explained by spatial filtering ('lateral inhibition') that can be approximated by 2nd derivative computation, and several alternative models have been proposed. To distinguish between them, we used a novel set of ‘generalised Gaussian’ images, in which the sharp ramp-plateau junction of the Mach ramp was replaced by smoother transitions. The images ranged from a slightly blurred Mach ramp to a Gaussian edge and beyond, and also included a sine-wave edge. The probability of seeing Mach Bands increased with the (relative) sharpness of the junction, but was largely independent of absolute spatial scale. These data did not fit the predictions of MIRAGE, nor 2nd derivative computation at a single fine scale. In experiment 2, observers used a cursor to mark features on the same set of images. Data on perceived position of Mach bands did not support the local energy model. Perceived width of Mach bands was poorly explained by a single-scale edge detection model, despite its previous success with Mach edges (Wallis & Georgeson, 2009, Vision Research, 49, 1886-1893). A more successful model used separate (odd and even) scale-space filtering for edges and bars, local peak detection to find candidate features, and the MAX operator to compare odd- and even-filter response maps (Georgeson, VSS 2006, Journal of Vision 6(6), 191a). Mach bands are seen when there is a local peak in the even-filter (bar) response map, AND that peak value exceeds corresponding responses in the odd-filter (edge) maps.
Resumo:
Object-oriented programming is seen as a difficult skill to master. There is considerable debate about the most appropriate way to introduce novice programmers to object-oriented concepts. Is it possible to uncover what the critical aspects or features are that enhance the learning of object-oriented programming? Practitioners have differing understandings of the nature of an object-oriented program. Uncovering these different ways of understanding leads to agreater understanding of the critical aspects and their relationship tothe structure of the program produced. A phenomenographic studywas conducted to uncover practitioner understandings of the nature of an object-oriented program. The study identified five levels of understanding and three dimensions of variation within these levels. These levels and dimensions of variation provide a framework for fostering conceptual change with respect to the nature of an object-oriented program.
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The main objective of this work was to examlne the various stages of the production of industrial laminates based on phenol-formaldehyde resins, with a view of suggesting ways of improving the process economics and/or the physical properties of the final product. Aspects of impregnation, drying, and lamination were investigated. The resins used in all experiments were ammonia-catalysed. Work was concentrated on the lamination stage since this is a labour intensive activity. Paper-phenolic lay-ups were characterised in terms of the temperatures experienced during cure, and a shorter cure-cycle is proposed, utilising the exothermic heat produced during pressing of 25.5 mm thick lay-ups. Significant savings in production costs and improvements in some of the physical properties have been achieved. In particular, water absorption has been reduced by 43-61%. Work on the drying stage has shown that rapid heating of the wet impregnated substrate results in resin solids losses. Drying at lower temperatures by reducing the driving force leads to more resin (up to 6.5%) being retained by the prepregs and therefore more effective use of an expensive raw material. The impregnation work has indicated that residence times above 6 seconds in the varnish bath enhance the insulation resistance of the final product, possibly due to improved resin distribution and reduction in water absorption. In addition, a novel process which involves production of laminates by in situ polymerisation of the phenolic resin on the substrate has been examined. Such a process would eliminate the solvent recovery plant - a necessary stage in current industrial processes. In situ polymerisation has been shown to be chemically feasible.
Resumo:
Practitioners and academics are in broad agreement that, above all, organizations need to be able to learn, to innovate and to question existing ways of working. This thesis develops a model to take into account, firstly, what determines whether or not organizations endorse practices designed to facilitate learning. Secondly, the model evaluates the impact of such practices upon organizational outcomes, measured in terms of products and technological innovation. Researchers have noted that organizations that are committed to producing innovation show great resilience in dealing with adverse business conditions (e.g. Pavitt, 1991; Leonard Barton, 1998). In effect, such organizations bear many of the characteristics associated with the achievement of ‘learning organization’ status (Garvin, 1993; Pedler, Burgoyne & Boydell, 1999; Senge, 1990). Seven studies are presented to support this theoretical framework. The first empirical study explores the antecedents to effective learning. The three following studies present data to suggest that people management practices are highly significant in determining whether or not organizations are able to produce sustained innovation. The thesis goes on to explore the relationship between organizational-level job satisfaction, learning and innovation, and provides evidence to suggest that there is a strong, positive relationship between these variables. The final two chapters analyze learning and innovation within two similar manufacturing organizations. One manifests relatively low levels of innovation whilst the other is generally considered to be outstandingly innovative. I present the comparative framework for exploring the different approaches to learning manifested by the two organizations. The thesis concludes by assessing the extent to which the theoretical model presented in the second chapter is borne out by the findings of the study. Whilst this is a relatively new field of inquiry, findings reveal that organizations have a much stronger chance of producing sustained innovation where they manage people proactively where people process themselves to be satisfied at work. Few studies to date have presented empirical evidence to substantiate theoretical endorsements to engage in higher order learning, so this research makes an important contribution to existing literature in this field.
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The thesis is concerned with the electron properties of single-polepiece magnetic electron lenses especially under conditions of extreme polepiece saturation. The electron optical properties are first analysed under conditions of high polepiece permeability. From this analysis, a general idea can be obtained of the important parameters that affect ultimate lens performance. In addition, useful information is obtained concerning the design of improved lenses operating under conditions of extreme polepiece saturation, for example at flux densities of the order of 10 Tesla. It is shown that in a single-polepiece lens , the position and shape of the lens exciting coil plays an important role. In particular, the maximum permissible current density in the windings,rather than the properties of the iron, can set a limit to lens performance. This factor was therefore investigated in some detail. The axial field distribution of a single-polepiece lens, unlike that of a conventional lens, is highly asymmetrical. There are therefore two possible physical arrangements of the lens with respect to the incoming electron beam. In general these two orientations will result in different aberration coefficients. This feature has also been investigated in some detail. Single-pole piece lenses are thus considerably more complicated electron- optically than conventional double polepiece lenses. In particular, the absence of the usual second polepiece causes most of the axial magnetic flux density distribution to lie outside the body of the lens. This can have many advantages in electron microscopy but it creates problems in calculating the magnetic field distribution. In particular, presently available computer programs are liable to be considerably in error when applied to such structures. It was therefore necessary to find independent ways of checking the field calculations. Furthermore, if the polepiece is allowed to saturate, much more calculation is involved since the field distribution becomes a non-linear function of the lens excitation. In searching for optimum lens designs, care was therefore taken to ensure that the coil was placed in the optimum position. If this condition is satisfied there seems to be no theoretical limit to the maximum flux density that can be attained at the polepiece tip. However , under iron saturation condition, some broadening of the axial field distribution will take place, thereby changing the lens aberrations . Extensive calculations were therefore made to find the minimum spherical and chromatic aberration coefficients . The focal properties of such lens designs are presented and compared with the best conventional double-polepiece lenses presently available.
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We have simulated the performance of various apertures used in Coded Aperture Imaging - optically. Coded pictures of extended and continuous-tone planar objects from the Annulus, Twin Annulus, Fresnel Zone Plate and the Uniformly Redundant Array have been decoded using a noncoherent correlation process. We have compared the tomographic capabilities of the Twin Annulus with the Uniformly Redundant Arrays based on quadratic residues and m-sequences. We discuss the ways of reducing the 'd. c.' background of the various apertures used. The non-ideal System-Point-Spread-Function inherent in a noncoherent optical correlation process produces artifacts in the reconstruction. Artifacts are also introduced as a result of unwanted cross-correlation terms from out-of-focus planes. We find that the URN based on m-sequences exhibits good spatial resolution and out-of-focus behaviour when imaging extended objects.
Resumo:
Qualitative research can make a valuable contribution to the study of quality and safety in health care. Sound ways of appraising qualitative research are needed, but currently there are many different proposals with few signs of an emerging consensus. One problem has been the tendency to treat qualitative research as a unified field. We distinguish universal features of quality from those specific to methodology and offer a set of minimally prescriptive prompts to assist with the assessment of generic features of qualitative research. In using these, account will need to be taken of the particular method of data collection and methodological approach being used. There may be a need for appraisal criteria suited to the different methods of qualitative data collection and to different methodological approaches. These more specific criteria would help to distinguish fatal flaws from more minor errors in the design, conduct, and reporting of qualitative research. There will be difficulties in doing this because some aspects of qualitative research, particularly those relating to quality of insight and interpretation, will remain difficult to appraise and will rely largely on subjective judgement.