923 resultados para pacs: information technolgy applications


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In Information Filtering (IF) a user may be interested in several topics in parallel. But IF systems have been built on representational models derived from Information Retrieval and Text Categorization, which assume independence between terms. The linearity of these models results in user profiles that can only represent one topic of interest. We present a methodology that takes into account term dependencies to construct a single profile representation for multiple topics, in the form of a hierarchical term network. We also introduce a series of non-linear functions for evaluating documents against the profile. Initial experiments produced positive results.

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This thesis is concerned with the development of hydrogels that adhere to skin and can be used for topical or trans dermal release of active compounds for therapeutic or cosmetic use. The suitability of a range of monomers and initiator systems for the production of skin adhesive hydro gels by photopolymerisation was explored and an approximate order of monomer reactivity in aqueous solution was determined. Most notably, the increased reactivity of N-vinyl pyrrolidone within an aqueous system, as compared to its low rate of polymerisation in organic solvents, was observed. The efficacy of a series of photoinitiator systems for the preparation of sheet hydrogels was investigated. Supplementary redox and thermal initiators were also examined. The most successful initiator system was found to be Irgacure 184, which is commonly used in commercial moving web production systems that employ photopolymerisation. The influence of ionic and non-ionic monomers, crosslinking systems, water and glycerol on the adhesive and dynamic mechanical behaviour of partially hydrated hydrogel systems was examined. The aim was to manipulate hydrogel behaviour to modify topical and transdermal delivery capability and investigated the possibility of using monomer combinations that would influence the release characteristics of gels by modifying their hydrophobic and ionic nature. The copolymerisation of neutral monomers (N-vinyl pyrrolidone, N,N-dimethyl acrylamide and N-acryloyl morpholine) with ionic monomers (2-acrylamido-2-methylpropane sulphonic acid; sodium salt, and the potassium salt of 3-sulphopropyl acrylate) formed the basis of the study. Release from fully and partially hydrated hydrogels was studied, using model compounds and a non-steroidal anti-inflammatory drug, Ibuprofen. Release followed a common 3-stage kinetic profile that includes an initial burst phase, a secondary phase of approximate first order release and a final stage of infinitesimally slow release such that the compound is effectively retained within the hydrogel. Use of partition coefficients, the pKa of the active and a knowledge of charge-based and polar interactions of polymer and drug were complementary in interpreting experimental results. In summary, drug ionisation, hydrogel composition and external release medium characteristics interact to influence release behaviour. The information generated provides the basis for the optimal design of hydrogels for specific dermal release applications and some understanding of the limitations of these systems for controlled release applications.

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This system is concerned with the design and implementation of a community health information system which fulfils some of the local needs of fourteen nursing and para-medical professions in a district health authority, whilst satisfying the statutory requirements of the NHS Korner steering group for those professions. A national survey of community health computer applications, documented in the form of an applications register, shows the need for such a system. A series of general requirements for an informations systems design methodology are identified, together with specific requirements for this problem situation. A number of existing methodologies are reviewed, but none of these were appropriate for this application. Some existing approaches, tools and techniques are used to define a more suitable methodology. It is unreasonable to rely on one single general methodology for all types of application development. There is a need for pragmatism, adaptation and flexibility. In this research, participation in the development stages by those who will eventually use the system was thought desirable. This was achieved by forming a representative design group. Results would seem to show a highly favourable response from users to this participation which contributed to the overall success of the system implemented. A prototype was developed for the chiropody and school nursing staff groups of Darlington health authority, and evaluations show that a significant number of the problems and objectives of those groups have been successfully addressed; the value of community health information has been increased; and information has been successfully fed back to staff and better utilised.

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This research examines the role of the information management process within a process-oriented enterprise, Xerox Ltd. The research approach is based on a post-positive paradigm and has resulted in thirty-five idiographic statements. The three major outcomes are: 1. The process-oriented holistic enterprise is an organisation that requires a long-term management commitment to its development. It depends on the careful management of people, tasks, information and technology. A complex integration of business processes is required and this can be managed through the use of consistent documentation techniques, clarity in the definition of process responsibilities and management attention to the global metrics and the centralisation of the management of the process model are critical to its success. 2. The role of the information management process within the context of a process-oriented enterprise is to provide flexible and cost-effective applications, technological, and process support to the business. This is best achieved through a centralisation of the management of information management and of the process model. A business-led approach combined with the consolidation of applications, information, process, and data architectures is central to providing effective business and process-focused support. 3. In a process oriented holistic enterprise, process and information management are inextricably linked. The model of process management depends heavily on information management, whilst the model of information management is totally focused around supporting and creating the process model. The two models are mutually creating - one cannot exist without the other. There is a duality concept of process and information management.

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In the last twenty or so years the results of theory and experiment have produced much information on the characteristics of gas-surface interactions relevant to a satellite in hyperthermal free-molecular flow. This thesis contains reviews of the rarefied gas dynamics applicable to satellites and has attempted to compare existing models of gas-surface interaction with contemporary knowledge of such systems. It is shown that a more natural approach would be to characterise the gas-surface interaction using the normal and tangential momentum accommodation coefficients, igma' and igma respectively, specifically in the form igma = constant , igma' = igma'0 -igma'1sec i where i is the angle subtended between the incident flow and the surface normal and igma,igma'0 and igma'1 are constants. Adopting these relationships, the effects of atmospheric lift on inclination, i, and atmospheric drag on the semi-major axis, a, and eccentricity, e, have been investigated. Applications to ANS-1 (1974-70A) show that the observed perturbation in i can be ascribed primarily to non-zero igma'1 whilst perturbations in a and e produce constraint equations between the three parameters. The numerical results seem to imply that a good theoretical orbit is achieved despite a much lower drag coefficient than anticipated by earlier theories.

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This thesis described the research carried out on the development of a novel hardwired tactile sensing system tailored for the application of a next generation of surgical robotic and clinical devices, namely a steerable endoscope with tactile feedback, and a surface plate for patient posture and balance. Two case studies are examined. The first is a one-dimensional sensor for the steerable endoscope retrieving shape and ‘touch’ information. The second is a two-dimensional surface which interprets the three-dimensional motion of a contacting moving load. This research can be used to retrieve information from a distributive tactile sensing surface of a different configuration, and can interpret dynamic and static disturbances. This novel approach to sensing has the potential to discriminate contact and palpation in minimal invasive surgery (MIS) tools, and posture and balance in patients. The hardwired technology uses an embedded system based on Field Programmable Gate Arrays (FPGA) as the platform to perform the sensory signal processing part in real time. High speed robust operation is an advantage from this system leading to versatile application involving dynamic real time interpretation as described in this research. In this research the sensory signal processing uses neural networks to derive information from input pattern from the contacting surface. Three neural network architectures namely single, multiple and cascaded were introduced in an attempt to find the optimum solution for discrimination of the contacting outputs. These architectures were modelled and implemented into the FPGA. With the recent introduction of modern digital design flows and synthesis tools that essentially take a high-level sensory processing behaviour specification for a design, fast prototyping of the neural network function can be achieved easily. This thesis outlines the challenge of the implementations and verifications of the performances.

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This thesis describes the work carried out on the development of a novel digit actuator system with tactile perception feedback to a user and demonstrated as a master-slave system. For the tactile surface of the digit, contrasting sensor elements of resistive strain gauges and optical fibre Bragg grating sensors were evaluated. A distributive tactile sensing system consisting of optimised neural networking schemes was developed, resulting in taxonomy of artificial touch. The device is suitable for use in minimal invasive surgical (MIS) procedures as a steerable tip and a digit constructed wholly from polymers makes it suitable for use in Magnetic Resonance Imaging (MRI) environments enabling active monitoring of the patient during a procedure. To provide a realistic template of the work the research responded to the needs of two contrasting procedures: palpation of the prostate and endotracheal intubation in anaesthesia where the application of touch sense can significantly assist navigation. The performance of the approach was demonstrated with an experimental digit constructed for use in the laboratory in phantom trials. The phantom unit was developed to resemble facets of the clinical applications and digit system is able to evaluate reactive force distributions acting over the surface of the digit as well as different descriptions of contact and motion relative to the surface of the lumen. Completing control of the digit is via an instrumented glove, such that the digit actuates in sympathy with finger gesture and tactile information feedback is achieved by a combination of the tactile and visual means.

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The research compares the usefullness of four remote sensing information sources, these being LANDSAT photographic prints, LANDSAT computer compatible tapes, Metric Camera and SIR-A photographic prints. These sources provide evaluations of the catchment characteristics of the Belize and Sibun river basins in Central America. Map evaluations at 1:250,000 scale are compared to the results of the same scale, remotely sensed information sources. The values of catchment characteristics for both maps and LANDSAT prints are used in multiple regression analysis, providing flood flow formulae, after investigations to provide a suitable dependent variable discharge series are made for short term records. The use of all remotely sensed information sources in providing evaluations of catchment characteristics is discussed. LANDSAT prints and computer compatible tapes of a post flood scene are used to estimate flood distributions and volumes. These are compared to values obtained from unit hydrograph analysis, using the dependent discharge series and evaluate the probable losses from the Belize river to the floodplain, thereby assessing the accuracy of LANDSAT estimates. Information relating to flood behaviour is discussed in terms of basic image presentation as well as image processing. A cost analysis of the purchase and use of all materials is provided. Conclusions of the research indicate that LANDSAT print material may provide information suitable for regression analysis at levels of accuracy as great as those of topographic maps, that the differing information sources are uniquely applicable and that accurate estimates of flood volumes may be determined even by post flood imagery.

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A comprehensive introduction to the technology, development and management of business information systems. The book assumes no prior knowledge of IS or IT, so that new concepts and terms are defined as clearly as possible, with explanations in the text, and definitions at the margin. In this fast-moving area, the book covers both the crucial underpinnings of the subject as well as the most recent business and technology applications. It is written for students on any IS, BIS or MIS course from undergraduate to postgraduate and MBA level within a Business or Computer Science Department.

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Continuing advances in digital image capture and storage are resulting in a proliferation of imagery and associated problems of information overload in image domains. In this work we present a framework that supports image management using an interactive approach that captures and reuses task-based contextual information. Our framework models the relationship between images and domain tasks they support by monitoring the interactive manipulation and annotation of task-relevant imagery. During image analysis, interactions are captured and a task context is dynamically constructed so that human expertise, proficiency and knowledge can be leveraged to support other users in carrying out similar domain tasks using case-based reasoning techniques. In this article we present our framework for capturing task context and describe how we have implemented the framework as two image retrieval applications in the geo-spatial and medical domains. We present an evaluation that tests the efficiency of our algorithms for retrieving image context information and the effectiveness of the framework for carrying out goal-directed image tasks. © 2010 Springer Science+Business Media, LLC.

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IEEE 802.15.4 standard has been recently developed for low power wireless personal area networks. It can find many applications for smart grid, such as data collection, monitoring and control functions. The performance of 802.15.4 networks has been widely studied in the literature. However the main focus has been on the modeling throughput performance with frame collisions. In this paper we propose an analytic model which can model the impact of frame collisions as well as frame corruptions due to channel bit errors. With this model the frame length can be carefully selected to improve system performance. The analytic model can also be used to study the 802.15.4 networks with interference from other co-located networks, such as IEEE 802.11 and Bluetooth networks. © 2011 Springer-Verlag.

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IEEE 802.15.4 networks (also known as ZigBee networks) has the features of low data rate and low power consumption. In this paper we propose an adaptive data transmission scheme which is based on CSMA/CA access control scheme, for applications which may have heavy traffic loads such as smart grids. In the proposed scheme, the personal area network (PAN) coordinator will adaptively broadcast a frame length threshold, which is used by the sensors to make decision whether a data frame should be transmitted directly to the target destinations, or follow a short data request frame. If the data frame is long and prone to collision, use of a short data request frame can efficiently reduce the costs of the potential collision on the energy and bandwidth. Simulation results demonstrate the effectiveness of the proposed scheme with largely improve bandwidth and power efficiency. © 2011 Springer-Verlag.

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Quality of services (QoS) support is critical for dedicated short range communications (DSRC) vehicle networks based collaborative road safety applications. In this paper we propose an adaptive power and message rate control method for DSRC vehicle networks at road intersections. The design objective is to provide high availability and low latency channels for high priority emergency safety applications while maximizing channel utilization for low priority routine safety applications. In this method an offline simulation based approach is used to find out the best possible configurations of transmit power and message rate for given numbers of vehicles in the network. The identified best configurations are then used online by roadside access points (AP) according to estimated number of vehicles. Simulation results show that this adaptive method significantly outperforms a fixed control method. © 2011 Springer-Verlag.

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Higher education institutions are increasingly using social software tools to support teaching and learning. Despite the fact that social software is often used in a social context, these applications can significantly contribute to the educational experience of a student. However, as the social software domain comprises a considerable diversity of tools, the respective tools can be expected to differ in the way they can contribute to teaching and learning. In this review on the educational use of social software, we systematically analyze and compare the diverse social software tools and identify their contributions to teaching and learning. By integrating established learning theory and the extant literature on the individual social software applications we seek to contribute to a theoretical foundation for social software use and the choice of tools. Case vignettes from several UK higher education institutions are used to illustrate the different applications of social software tools in teaching and learning.

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A comprehensive introduction to the technology, development and management of business information systems. The book assumes no prior knowledge of IS or IT, so that new concepts and terms are defined as clearly as possible, with explanations in the text, and definitions at the margin. In this fast-moving area, the book covers both the crucial underpinnings of the subject as well as the most recent business and technology applications.It is written for students on any IS, BIS or MIS course from undergraduate to postgraduate and MBA level within a Business or Computer Science Department - See more at: http://catalogue.pearsoned.ca/educator/product/Business-Information-Systems-Technology-Development-and-Management-for-the-EBusiness/9780273716624.page#sthash.LgAheK57.dpuf