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Full Integration (full + integration)
Selected AbstractsOn reduced integration and locking of flat shell finite elements with drilling rotationsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 2 2003Sannelie Geyer Abstract In recent times, a number of assumed stress membrane finite elements with drilling degrees of freedom have been presented. These highly accurate elements are natural candidates for the membrane component of geometrically simple, yet accurate, flat shell finite elements. Depending on a mixed formulation, these assumed stress membranes are normally integrated using full integration. However, this is not necessarily optimal. Reduced integration using modified quadratures decreases the effects of membrane-bending locking, while the accuracy and rank of the formulation is not impaired. Copyright ©2003 John Wiley & Sons, Ltd. [source] A practical large-strain solid finite element for sheet formingINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 4 2005Jue Wang Abstract An alternative approach for developing practical large-strain finite elements has been introduced and used to create a three-dimensional solid element that exhibits no locking or hourglassing, but which is more easily and reliably derived and implemented than typical reduced-integration schemes with hourglassing control. Typical large-strain elements for forming applications rely on reduced integration to remove locking modes that occur with the coarse meshes that are necessary for practical use. This procedure introduces spurious zero-energy deformation modes that lead to hourglassing, which in turn is controlled by complex implementations that involve lengthy derivations, knowledge of the material model, and/or undetermined parameters. Thus, for a new material or new computer program, implementation of such elements is a daunting task. Wang,Wagoner-3-dimensions (WW3D), a mixed, hexahedral, three-dimensional solid element, was derived from the standard linear brick element by ignoring the strain components corresponding to locking modes while maintaining full integration (8 Gauss points). Thus, WW3D is easily implemented for any material law, with little chance of programming error, starting from programming for a readily available linear brick element. Surprisingly, this approach and resulting element perform similarly or better than standard solid elements in a series of numerical tests appearing in the literature. The element was also tested successfully for an applied sheet-forming analysis problem. Many variations on the scheme are also possible for deriving special-purpose elements. Copyright © 2005 John Wiley & Sons, Ltd. [source] Two simple and efficient displacement-based quadrilateral elements for the analysis of composite laminated platesINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 11 2004Y. X. Zhang Abstract Two simple 4-node 20-DOF and 4-node 24-DOF displacement-based quadrilateral elements named RDKQ-L20 and RDKQ-L24 are developed in this paper based on the first-order shear deformation theory (FSDT) for linear analysis of thin to moderately thick laminates. The deflection and rotation functions of the element sides are obtained from Timoshenko's laminated composite beam functions. Linear displacement interpolation functions of the standard 4-node quadrilateral isoparametric plane element and displacement functions of a quadrilateral plane element with drilling degrees of freedom are taken as in-plane displacements of the proposed elements RDKQ-L20 and RDKQ-L24, respectively. Due to the application of Timoshenko's laminated composite beam functions, convergence can be ensured theoretically for very thin laminates. The elements are simple in formulation, and shear-locking free for extremely thin laminates even with full integration. A hybrid-enhanced procedure is employed to improve the accuracy of stress analysis, especially for transverse shear stresses. Numerical tests show that the new elements are convergent, not sensitive to mesh distortion, accurate and efficient for analysis of thin to moderately thick laminates. Copyright © 2004 John Wiley & Sons, Ltd. [source] Interference evaluations and simulations for multisatellite multibeam systemsINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 4 2002Pierpaolo Loreti Third generation communication systems will be characterized by full integration between terrestrial and satellite components. To this aim, global coverage along with not severe requirements for user terminals are mandatory for the satellite segment and the use of constellations of satellites in low or medium Earth orbits (LEO or MEO) seems to be a viable solution. Those satellite systems will adopt multibeam antennas to achieve high spectral efficiency and low-cost terminals. Thus, interference becomes one of the most limiting factors in terms of both link availability and capacity. The paper presents a more complete interference model than previously published in literature. The identification of the interfering users set has been introduced and all the factors impacting interference generation or isolation have been considered in case of both FDMA and CDMA access. This model is suitable for instantaneous analysis of multisatellite constellations. It has been implemented and time-domain simulations have been performed to evaluate the impairments due to co-channel interference for different access techniques for LEO configuration. Simulation results on interference and users spatial distribution, on trade-offs between interference and system capacity will be presented. Finally, the main interference mitigation techniques will be listed and discussed. Copyright © 2002 John Wiley & Sons, Ltd. [source] Where is the wisdom?JOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 6 2009A conceptual history of evidence-based medicine Abstract Rationale, Evidence-based medicine (EBM) has been acclaimed as a major advance in medical science, but criticized as a proposed alternative model for the practice and teaching of medicine. Ambiguity regarding the proper role of the contributions of EBM within the fabric of medicine and health care has contributed to this discrepancy. Aims and objectives, We undertook a critical review of the history of the EBM movement, beginning with its origins in the 1970s and continuing through this century. We drew upon the results of an independent project that rationalized the EBM domain from the perspective of educational evaluation and assessment. We considered the content of EBM in relationship to the propositions and promises embodied in advocacy publications. Results, EBM emerged in the context of the explosion of biomedical information in the decade preceding public access to the Internet in the mid-1990s and drew upon the independently derived ,information literacy' formula developed by information scientists during the 1980s. The critically important content and achievements of EBM are fully explained within the confines of the information literacy model. The thesis that EBM offers an alternative paradigm for individualized health care, asserted in the advocacy literature, is not supported by published models of evidence-based clinical practice. Conclusion, A critical historical review of the origins, content and development of the EBM movement proposes that full integration of the fruits of the movement into routine clinical care remains a conceptual and practical challenge. [source] Clinical governance in practice: closing the loop with integrated audit systemsJOURNAL OF PSYCHIATRIC & MENTAL HEALTH NURSING, Issue 2 2006L. TAYLOR ba hons rmn Clinical governance has been acknowledged as the driving force behind National Health Service (NHS) reform since the government white paper outlined a new style of NHS in the UK in 1997. The framework of clinical governance ensures that NHS organizations are accountable for continually improving the quality of their services and safeguarding high standards of care by creating an environment in which excellence in clinical care will develop. A major component of a clinical governance framework requires utilizing audit procedures, which assess the effectiveness of current systems and ultimately direct continual quality improvement. This paper describes the audit component of a local clinical governance framework designed for a unit based within an NHS trust, which has utilized a multidisciplinary approach to assess the effectiveness of a newly commissioned service and its impact on the residents and staff. The unit is a 12-bedded, low-secure-intensive rehabilitation unit for clients with severe and enduring mental illness. Using recognized and standardized psychometric outcome measures, information was collected on clinical symptoms, social functioning, social behaviour, quality of life, relationship quality with named nurses and medication side-effects. Additionally, confidential staff measures were included to assess levels of burnout, identify expressed emotion and assess staff perception of models of illness. The paper includes a comprehensive account of how managerial commitment, teaching processes and application of technology ensured prompt data collection and maintained the momentum through the audit timescale. Data analysis and presentation of data in both clinical reviews and in senior management meetings within the unit are discussed. Findings highlight the full integration of the audit system into the processes of the unit. Clinically, the paper highlights the enhancement of the knowledge base of the client group and the influence on clinical decision-making processes and care delivery as a result of the audit. Brief clinical examples are given. In conclusion, the impact of the audit on unit strategy and organizational efficiency are discussed to highlight the importance of closing the audit loop and completing the cycle of clinical governance. The audit system has positive implications for replication in other services. [source] Development and validation of a spectral library searching method for peptide identification from MS/MSPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 5 2007Henry Lam Abstract A notable inefficiency of shotgun proteomics experiments is the repeated rediscovery of the same identifiable peptides by sequence database searching methods, which often are time-consuming and error-prone. A more precise and efficient method, in which previously observed and identified peptide MS/MS spectra are catalogued and condensed into searchable spectral libraries to allow new identifications by spectral matching, is seen as a promising alternative. To that end, an open-source, functionally complete, high-throughput and readily extensible MS/MS spectral searching tool, SpectraST, was developed. A high-quality spectral library was constructed by combining the high-confidence identifications of millions of spectra taken from various data repositories and searched using four sequence search engines. The resulting library consists of over 30,000 spectra for Saccharomyces cerevisiae. Using this library, SpectraST vastly outperforms the sequence search engine SEQUEST in terms of speed and the ability to discriminate good and bad hits. A unique advantage of SpectraST is its full integration into the popular Trans Proteomic Pipeline suite of software, which facilitates user adoption and provides important functionalities such as peptide and protein probability assignment, quantification, and data visualization. This method of spectral library searching is especially suited for targeted proteomics applications, offering superior performance to traditional sequence searching. [source] Aerial archaeology: a full digital workflow for aerial photographyARCHAEOLOGICAL PROSPECTION, Issue 4 2005Jürg Leckebusch Abstract Aerial archaeology is an established prospection method, but its systems and techniques have changed very little since its first applications. The advent of modern high-resolution digital cameras, with better image resolution and image depth than comparable analogue photography, offers the possibility of a full digital workflow. A new system is being developed to fulfil all the requirements of aerial archaeology. The images are stored on a PC, together with associated geographical data, including the location and orientation of the camera stations. A GIS displays the camera stations together with the flight path. Once the photographic record of a site is finished, the geographical co-ordinates of the target are calculated automatically, and combined with other data from a simple user interface to provide a complete primary data set during the flight. This allows the investigator to spend more time searching for sites during the flight, and simplifies the interpretation and analysis of the images in the office. This paper presents several new approaches to full integration of the systems involved. Copyright © 2005 John Wiley & Sons, Ltd. [source] | |||||||||||||