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81.
Route following based on visual landmark matching may require many models to cover all different situations. This paper describes a system that is able to adapt template's modelling parameters to environmental conditions (lighting, shadows, etc.) by a genetic learning technique. In addition, the mobile robot self-localisation is obtained by a stereo approach that uses the centres of matching in the two images to solve in a simple way the correspondence problem in the 3D position estimation. The experimental results show that the tracking robustness is improved, while using a small set of templates.  相似文献   
82.
The surgical experience in 13 infants with total anomalous pulmonary venous connection (TAPVC) between 1987 and 1991 is reviewed. The age vary from 2 days to 35 months with a weight at intervention from 2.130 kg to 5.400 kg. The types of TAPVC were supracardiac in 4 patients, cardiac in 4, and infracardiac in 5. Seven patients (54%) were operated on in emergency. Cardiopulmonary bypass consisted of profound hypothermia and total circulatory arrest in 8 patients (60%) and continuous hypothermic bypass with low flow for the remaining 5 patients (40%). There was no operative death. The follow-up ranges from 21 to 58 months, mean 40 months. There was one reoperation. All the patients were asymptomatic and the height growth percentile is less than 5% in 20%, and the weight growth percentile is less than 5% in 30%. The early repair of infants born with TAPVC can be done with low morbidity with a good prospect on medium term follow-up.  相似文献   
83.
In this work we evaluated the photophysical and in vitro properties of Foscan, a second-generation photosensitizer drug (PS) widely used in systemic clinical protocols for cancer therapy based on Photodynamic Therapy (PDT). We employed biodegradable nanoemulsions (NE) as a colloidal vehicle of the oil/water (o/w) type focusing in topical administration of Foscan and other photosensitizer drugs. This formulation was obtained and stabilized by the methodology described by Tabosa do Egito et al., based on the mixture of two phases: an aqueous solution and an organic medium consisting of nonionic surfactants and oil. The photodynamic potential of the drug incorporated into the NE was studied by steady-state and time-resolved spectroscopic techniques. We also analyzed the in vitro biological behavior carried out in mimetic biological environment protocols based on the animal model. After topical application in a skin animal model, we evaluated the Foscan/NE diffusion flux into the skin layers (stratum corneum and epidermis + dermis) by classical procedures using Franz Diffusion cells. Our results showed that the photophysical properties of PS were maintained after its incorporation into the NE when compared with homogeneous organic medium. The in vitro assays enabled the determination of an adequate profile for the interaction of this system in the different skin layers, with an ideal time lag of 6 h after topical administration in the skin model. The Foscan diffusion flux (J) was increased when this PS was incorporated into the NE, if compared with its flux in physiological medium. These parameters demonstrated that the NE can be potentially applied as a drug delivery system (DDS) for Foscan in both in vitro and in vivo assays, as well as in future clinical applications involving topical skin cancer PDT.  相似文献   
84.
This article describes an oscilloscope method for eliminating the interference and disturbance voltages for the earthing measurements of large, extended or interconnected earthing systems in substations where the impedance to earth is very low (|ZE| < 0.3 Ω). The presented oscilloscope method is based on a heavy-current injected method at network frequency. Two ways of obtaining the final result from oscilloscope measurements are described and presented with practical examples. The accuracy of this method using an oscilloscope was confirmed by a comparison with results obtained using conventional methods for practical cases of touch-voltage measurements, i.e., the beat method and the polarity-reversal method. These comparative measurements were made in three substations. The article also describes the advantages of this method.  相似文献   
85.
This article is concerned with the finite element implementation of an elasto‐visco‐plastic constitutive model using a symbolic approach. The model combines the Knauss–Emri (KE) pressure, temperature, and time superposition principle in the implicit finite element scheme. The equation development and code generation was performed using the symbolic tool AceGen. The same symbolic system was applied to derive analytical sensitivities of the numerical model with respect to the material and shape parameters. To enable efficient numerical implementation of the KE model the convolution integrals were transformed into their respective incremental forms, so that radical improvements of code efficiency and computer storage requirements were achieved. The numerical examples derived for polyethylene terephthalate (PET) polymers demonstrate that symbolic systems can be applied to develop complex constitutive models capable of simulating material responses that are in good agreement with experimental measurements over a wide range of strain rates, temperatures, and loading conditions. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
86.
The in-air beamline at the microanalytical center of the Jo?ef Stefan Institute in Slovenia has recently been upgraded with a wire-mesh current-integration normalization device and a RBS detector in helium flush. For positioning of the targets, the laser-triangulation with 40 μm repeatability was realized using 100 μm wide laser beam and a static camera. Metal plated historical objects were investigated for their gilded and tinned surfaces. Artificial samples were produced by dip-tinning and compared with archaeological samples. A surface roughness was found to be an important parameter for fitting the spectra by the SIMNRA software.  相似文献   
87.
The XFEM is a powerful method to handle strong discontinuities in a finite element environment, especially in the study of the final stages of material failure, modelling the propagation of cracks, suppressing the need of remeshing. Nevertheless, for some materials undergoing large strain processes without noticeable volume changes, the discretization technique employed must not only describe the material behaviour but also correctly address the incompressibility constraints. In order to develop a robust formulation for this type of problems, an approach based on the analyses of the underlying sub-space of incompressible deformations embedded in the XFEM approximation is used, in the context of both infinitesimal and finite strains. This study motivated the extension of the conventional formulations of B-bar and F-bar to include the XFEM enrichment functions, whose performance is evaluated through some numerical examples and compared with competing methods such as the enhanced strain formulation.  相似文献   
88.
Bach remedies were identified by Dr Edward Bach, a physician and homoeopath. Bach flower remedies consist of 38 remedies which are designed as a system of emotional healing. Remedies are dispensed in homoeopathic dosages, are safe and do not appear to interfere with any other medication. Nurses may find the remedies a useful adjunct to their nursing care.  相似文献   
89.
Fast chain coding of region boundaries   总被引:10,自引:0,他引:10  
A fast single-pass algorithm to convert a multivalued image from a raster-based representation into chain codes is presented. All chain codes are obtained in linear time with respect to the number of chain segments that are generated at each raster according to a set of templates. A formal statement and the complexity and performance analysis of the algorithm are given  相似文献   
90.
The paper discusses the role of scientometric indicators in peer-review selection of research project proposals. An ex post facto evaluation was made of three calls for research project proposals in Slovenia: 2003 with a peer review system designed in a way that conflict of interest was not avoided effectively, 2005 with a sound international peer-review system with minimized conflict of interest influence but a limited number of reviewers, and 2008 with a combination of scientometric indicators and a sound international peer review with minimized conflict of interest influence. The hypothesis was that the three different peer review systems would have different correlations with the same set of scientometric indicators. In the last two decision-making systems (2005 and 2008) where conflict of interest was effectively avoided, we have a high percentage (65%) of projects that would have been selected in the call irrespective of the method (peer review or bibliometrics solely). In contrast, in the 2003 call there is a significantly smaller percentage (49%) of projects that would have been selected in the call irrespective of the method (peer review or bibliometrics solely). It was shown that while scientometric indicators can hardly replace the peer-review system as the ultimate decision-making and support system, they can reveal its weaknesses on one hand and on the other can verify peer-review scores and minimize conflict of interest if necessary.  相似文献   
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