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51.
Clemente Neves Sousa Paulo Teles Vanessa Filipa Ferreira Dias João Luís Alves Apóstolo Maria Henriqueta Jesus Silva Figueiredo Maria Manuela Martins 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(3):695-699
Vascular access is one of the leading causes of mobilization of financial resources in health systems for people with chronic kidney disease on hemodialysis. Physical examination of the arteriovenous fistula (AVF) has demonstrated its effectiveness in identifying complications. We decided to evaluate the influence of nurses' professional experience in the detection of complications of the AVF (venous stenosis and steal syndrome). The study took place in eight hemodialysis centers between May and September of 2011 in the north of Portugal. Sample was constituted by registered nurses. The nurses involved in the experiment were divided in two groups: those who had more than 5 years of experience and those who had less than 5 years of experience. Ninety‐two nurses participated in the study: 34 nurses had less than 5 years of professional experience and 58 had more than 5 years of professional experience. In the practices considered by nurses in the detection of venous stenosis, there were no differences observed between the groups (P > 0.05). In steal syndrome, there were no differences observed between the groups in the practices of the nurses in the detection of this complication of the AVF (P > 0.05). We concluded that professional experience does not influence the detection of venous stenosis and steal syndrome. 相似文献
52.
53.
Paulo De Jesus 《连接科学》2014,26(3):293-296
The “Varieties of Enactivism: A Conceptual Geography” 4th April 2014, was a one day symposium which took place at Goldsmith University, London. The symposium had the explicit aim of clarifying the status of enactive cognitive science both as a unified paradigm for cognitive science and in relation to the broader embodied cognition framework. In what follows I offer a brief summery of the various talks followed by some thoughts on the current state of play within enactivism. 相似文献
54.
Abstract. The choice of the bandwidth in the local log-periodogram regression is of crucial importance for estimation of the memory parameter of a long memory time series. Different choices may give rise to completely different estimates, which may lead to contradictory conclusions, for example about the stationarity of the series. We propose here a data-driven bandwidth selection strategy that is based on minimizing a bootstrap approximation of the mean-squared error (MSE). Its behaviour is compared with other existing techniques for optimal bandwidth selection in a MSE sense, revealing its better performance in a wider class of models. The empirical applicability of the proposed strategy is shown with two examples: the widely analysed in a long memory context Nile river annual minimum levels and the input gas rate series of Box and Jenkins. 相似文献
55.
56.
María D. Perez-Godoy Antonio J. Rivera Francisco J. Berlanga María José Del Jesus 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2010,14(9):953-971
This paper presents a new evolutionary cooperative–competitive algorithm for the design of Radial Basis Function Networks
(RBFNs) for classification problems. The algorithm, CO2RBFN, promotes a cooperative–competitive environment where each individual represents a radial basis function (RBF) and the
entire population is responsible for the final solution. The proposal considers, in order to measure the credit assignment
of an individual, three factors: contribution to the output of the complete RBFN, local error and overlapping. In addition,
to decide the operators’ application probability over an RBF, the algorithm uses a Fuzzy Rule Based System. It must be highlighted
that the evolutionary algorithm considers a distance measure which deals, without loss of information, with differences between
nominal features which are very usual in classification problems. The precision and complexity of the network obtained by
the algorithm are compared with those obtained by different soft computing methods through statistical tests. This study shows
that CO2RBFN obtains RBFNs with an appropriate balance between accuracy and simplicity, outperforming the other methods considered. 相似文献
57.
Personal memories composed of digital pictures are very popular at the moment. To retrieve these media items annotation is
required. During the last years, several approaches have been proposed in order to overcome the image annotation problem.
This paper presents our proposals to address this problem. Automatic and semi-automatic learning methods for semantic concepts
are presented. The automatic method is based on semantic concepts estimated using visual content, context metadata and audio
information. The semi-automatic method is based on results provided by a computer game. The paper describes our proposals
and presents their evaluations. 相似文献
58.
Alfredo S. Ribeiro Abílio M.P. de Jesus António M. Lima José L.C. Lousada 《Construction and Building Materials》2009,23(8):2738-2745
The application of the concept of glued-laminated wood (glulam) to improve the mechanical properties of the solid wood of the maritime pine (Pinus pinaster) is the subject of this work. Two reinforced glued-laminated wood beams are proposed and assessed. The first is based on a concept of laminated wood composite with fiber glass; the second is based on the application of pultruded lamellas glued to the most stressed tensile region of the glued-laminated beams. In order to demonstrate the potential of the proposed strengthening solutions, a comparison between their mechanical behaviors and the mechanical behaviors of the conventional glued-laminated and solid beams are performed. Static load–deflection curves, an equivalent Young’s modulus, the ultimate strain and modulus of rupture are determined using 3-point quasi-static bending tests. In general, it is demonstrated the beneficial effect of the proposed strengthening solutions both in terms of resistance and ductility. 相似文献
59.
A numerical model for the coupled analysis of cross-sections made of anisotropic materials under general combined loading was formulated in an accompanying paper (1). In this paper, additional aspects concerning its implementation and the scheme for nonlinear analysis are discussed. The model is validated by analyzing several isotropic and anisotropic elastic problems; excellent accuracy was obtained compared to closed-form solutions. Further, the case of a RC section presenting crack-induced anisotropy is investigated. The capability of the model to capture interactions between tangent and normal forces is proved. The conclusion drawn is that the developed model is a suitable sectional constitutive equation for 3D beam elements for realistic structural analysis. 相似文献
60.
Leonidas G. Bleris Jesus Garcia Mayuresh V. Kothare Mark G. Arnold 《Journal of Process Control》2006,16(3):255-264
We propose a framework for embedding model predictive control for Systems-on-a-Chip applications. In order to allow the implementation of such a computationally expensive controller on chip, we propose reducing the precision of the microprocessor to the minimum while maintaining near optimal control performance. Taking advantage of the low precision, a logarithmic number system based microprocessor architecture is used, that allows the design of a reduced size processor, providing further energy and computational cost savings. The design parameters for this high-performance embedded controller are chosen using a combination of finite element method simulations and bit-accurate hardware emulations in a number of parametric tests. We provide the methodology for choosing the design parameters for two particular control problems; the temperature regulation in a wafer cross-section geometry, and the control of temperature in a non-isothermal fluid flow problem in a microdevice. Finally, we provide the microprocessor architecture details and estimates for the performance of the resulting embedded model predictive controller. 相似文献