1,305,480 research outputs found

    An Analytical Comparison of BIM based MEP Design v s Traditional 2D Design , with BIM Level 2 Implementation Considerations

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    Building information modeling (BIM) and 3D software design tools have been proffered as a significant technical advance on traditional design methods for the mechanical, electrical and plumbing (MEP) sector. However, there seems to be contrasting BIM related information regarding its potential benefits, who gains from those benefits, and the best implementation methods for BIM Level 2. The purpose of this paper was to establish if implementing BIM 3D design softwares has some standalone benefits for a MEP design office still working in traditional design methods, irrespective of BIM Level 2. Once this was established, the paper investigated if 3D software design implementation could be an efficient first step towards the introduction of BIM Level 2 for a MEP design company. A mixed method research methodology was used. A literature review was carried out on traditional design methods, on BIM based design methods, and on BIM implementation methods and potential barriers. A design analysis comparison study was carried out on the design of a ducted heating, cooling, air conditioning (HVAC) system for an office building. The comparison of results generated from traditional design methods against those generated from the BIM design tool MagiCAD was carried out and analysed. Qualitative research was also carried out through interviews with a number of experienced MEP designers. Through triangulation of the data collected from these three research methods, the findings of this report were that BIM 3D design tool implementation offers many benefits to a MEP design office, whether considering full BIM Level 2 implementation or not. However, if 3D modeling was a good first step to BIM implementation was less clear. What was apparent however was that the proper managing and controlling of the steps to BIM Level 2 implementation is arguably even more critical than deciding on the actual first step

    Integrated control/structure optimization by multilevel decomposition

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    A method for integrated control/structure optimization by multilevel decomposition is presented. It is shown that several previously reported methods were actually partial decompositions wherein only the control was decomposed into a subsystem design. One of these partially decomposed problems was selected as a benchmark example for comparison. The system is fully decomposed into structural and control subsystem designs and an improved design is produced. Theory, implementation, and results for the method are presented and compared with the benchmark example

    Implementation of a disability management policy in a large healthcare employer: a quasi-experimental, mixed-method evaluation

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    Objective: This study describes the process and outcomes of the implementation of a strengthened disability management policy in a large Canadian healthcare employer. Key elements of the strengthened policy included an emphasis on early contact, the training of supervisors and the integration of union representatives in return-to-work (RTW) planning. Design: The study applied mixed methods, combining a process evaluation within the employer and a quasi-experimental outcome evaluation between employers for a 3-year period prior to and following policy implementation in January 2012. Participants: Staff in the implementation organisation (n=4000) and staff in a peer group of 29 large hospitals (n=1 19 000). Outcomes: Work disability episode incidence and duration. Results: Both qualitative and quantitative measures of the implementation process were predominantly positive. Over the 6-year observation period, there were 624 work disability episodes in the organisation and 8604 in the comparison group of 29 large hospitals. The annual per cent change in episode incidence in the organisation was −5.6 (95% CI −9.9 to −1.1) comparable to the annual per cent change in the comparison group: −6.2 (-7.2 to –5.3). Disability episode durations also declined in the organisation, from a mean of 19.4 days (16.5, 22.3) in the preintervention period to 10.9 days (8.7, 13.2) in the postintervention period. Reductions in disability durations were also observed in the comparison group: from a mean of 13.5 days (12.9, 14.1) in the 2009–2011 period to 10.5 days (9.9, 11.1) in the 2012–2014 period. Conclusion: The incidence of work disability episodes and the durations of work disability declined strongly in this hospital sector over the 6-year observation period. The implementation of the organisation’s RTW policy was associated with larger reductions in disability durations than observed in the comparison group

    Implementation of a disability management policy in a large healthcare employer: a quasi-experimental, mixed-method evaluation

    Get PDF
    Objective: This study describes the process and outcomes of the implementation of a strengthened disability management policy in a large Canadian healthcare employer. Key elements of the strengthened policy included an emphasis on early contact, the training of supervisors and the integration of union representatives in return-to-work (RTW) planning. Design: The study applied mixed methods, combining a process evaluation within the employer and a quasi-experimental outcome evaluation between employers for a 3-year period prior to and following policy implementation in January 2012. Participants: Staff in the implementation organisation (n=4000) and staff in a peer group of 29 large hospitals (n=1 19 000). Outcomes: Work disability episode incidence and duration. Results: Both qualitative and quantitative measures of the implementation process were predominantly positive. Over the 6-year observation period, there were 624 work disability episodes in the organisation and 8604 in the comparison group of 29 large hospitals. The annual per cent change in episode incidence in the organisation was −5.6 (95% CI −9.9 to −1.1) comparable to the annual per cent change in the comparison group: −6.2 (-7.2 to –5.3). Disability episode durations also declined in the organisation, from a mean of 19.4 days (16.5, 22.3) in the preintervention period to 10.9 days (8.7, 13.2) in the postintervention period. Reductions in disability durations were also observed in the comparison group: from a mean of 13.5 days (12.9, 14.1) in the 2009–2011 period to 10.5 days (9.9, 11.1) in the 2012–2014 period. Conclusion: The incidence of work disability episodes and the durations of work disability declined strongly in this hospital sector over the 6-year observation period. The implementation of the organisation’s RTW policy was associated with larger reductions in disability durations than observed in the comparison group

    The SOS Platform: Designing, Tuning and Statistically Benchmarking Optimisation Algorithms

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    open access articleWe present Stochastic Optimisation Software (SOS), a Java platform facilitating the algorithmic design process and the evaluation of metaheuristic optimisation algorithms. SOS reduces the burden of coding miscellaneous methods for dealing with several bothersome and time-demanding tasks such as parameter tuning, implementation of comparison algorithms and testbed problems, collecting and processing data to display results, measuring algorithmic overhead, etc. SOS provides numerous off-the-shelf methods including: (1) customised implementations of statistical tests, such as the Wilcoxon rank-sum test and the Holm–Bonferroni procedure, for comparing the performances of optimisation algorithms and automatically generating result tables in PDF and formats; (2) the implementation of an original advanced statistical routine for accurately comparing couples of stochastic optimisation algorithms; (3) the implementation of a novel testbed suite for continuous optimisation, derived from the IEEE CEC 2014 benchmark, allowing for controlled activation of the rotation on each testbed function. Moreover, we briefly comment on the current state of the literature in stochastic optimisation and highlight similarities shared by modern metaheuristics inspired by nature. We argue that the vast majority of these algorithms are simply a reformulation of the same methods and that metaheuristics for optimisation should be simply treated as stochastic processes with less emphasis on the inspiring metaphor behind them

    FIXES, a system for automatic selection of set-ups and design of fixtures

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    This paper reports on the development of a computer aided planning system for the selection of set-ups and the design of fixtures in part manufacturing. First, the bottlenecks in the present planning methods are indicated. A brief description is given of the CAPP environment PART, in which FIXES is incorporated. The planning procedure of FIXES consists of two parts: the selection of set-ups and the design of a fixture for each set-up. The automatic selection of set-ups is based on the comparison of the tolerances of the relations between the different shape elements of the part. A tolerance factor has been developed to be able to compare the different tolerances. The system automatically selects the positioning faces and supports the selection of tools for positioning, clamping and supporting the part. A prototype implementation of FIXES is discussed

    High performance interior point methods for three-dimensional finite element limit analysis

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    The ability to obtain rigorous upper and lower bounds on collapse loads of various structures makes finite element limit analysis an attractive design tool. The increasingly high cost of computing those bounds, however, has limited its application on problems in three dimensions. This work reports on a high-performance homogeneous self-dual primal-dual interior point method developed for three-dimensional finite element limit analysis. This implementation achieves convergence times over 4.5× faster than the leading commercial solver across a set of three-dimensional finite element limit analysis test problems, making investigation of three dimensional limit loads viable. A comparison between a range of iterative linear solvers and direct methods used to determine the search direction is also provided, demonstrating the superiority of direct methods for this application. The components of the interior point solver considered include the elimination of and options for handling remaining free variables, multifrontal and supernodal Cholesky comparison for computing the search direction, differences between approximate minimum degree [1] and nested dissection [13] orderings, dealing with dense columns and fixed variables, and accelerating the linear system solver through parallelization. Each of these areas resulted in an improvement on at least one of the problems in the test set, with many achieving gains across the whole set. The serial implementation achieved runtime performance 1.7× faster than the commercial solver Mosek [5]. Compared with the parallel version of Mosek, the use of parallel BLAS routines in the supernodal solver saw a 1.9× speedup, and with a modified version of the GPU-enabled CHOLMOD [11] and a single NVIDIA Tesla K20c this speedup increased to 4.65×

    How to deal with the challenges of linking a large number of individual national models: the case of the AGMEMOD Partnership

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    The AGMEMOD Partnership seeks to capture the inherent existing heterogeneity of agricultural systems by linking together individual EU Member State models, an aggregated EU model and several accession countries into one single model, while still maintaining analytical consistency. Although this approach facilitates the comparison of the impact of a policy change across different Member States, it generates challenges in practical implementation, ranging from significant communication and administration requirements, to aggregation and consistency issues. This contribution provides insights into the different challenges posed to the scientists and discusses the key issues for maintenance and further development of such a complex system. Specific attention is paid to technical devices and tools as well as to the design of institutional settings to achieve consistency.linking models, policy analysis, partial equilibrium modelling, Common Agricultural Policy (CAP), Agricultural and Food Policy, Research Methods/ Statistical Methods,

    Montgomery and RNS for RSA Hardware Implementation

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    There are many architectures for RSA hardware implementation which improve its performance. Two main methods for this purpose are Montgomery and RNS. These are fast methods to convert plaintext to ciphertext in RSA algorithm with hardware implementation. RNS is faster than Montgomery but it uses more area. The goal of this paper is to compare these two methods based on the speed and on the used area. For this purpose the architecture that has a better performance for each method is selected, and some modification is done to enhance their performance. This comparison can be used to select the proper method for hardware implementation in both FPGA and ASIC design
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