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991.
A DSP-Based Remote Control Laboratory   总被引:1,自引:0,他引:1  
This paper presents a framework for rapid remote experiment implementation in the field of automatic control. The proposed solution is based on in-house developed embedded control hardware and two commercially available software packages. MATLAB/Simulink is used for rapid experiment control algorithm development, while LabVIEW is used for the user front-end and remote control. A combination of presented hardware and software solutions enables the rapid and easy creation of different interactive remote control experiments. Using this solution, a digital-signal-processor-based remote control laboratory for teaching purposes has been realized. This remote laboratory enables the remote users to easily interact with a set of physical control experiments through the Internet. In the friendly user interface, the remote user can change predefined system parameters and observe system response in textual, graphical, or video format. In addition, this remote laboratory includes a booking system, which enables remote users to book experiments in advance.  相似文献   
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We introduce a random perturbed version of the classical fidelity and we show that it converges with the same rate of decay of correlations, but not uniformly in the noise. This makes the classical fidelity unstable in the zero-noise limit.  相似文献   
996.
Neutral community theory explains biodiversity, i.e. the coexistence of several species, as the result of a stochastic balance between immigration and extinction on a local level, and between speciation and extinction on a regional level. The most popular model, presented by Hubbell in 2001, has seen many analytical developments in recent years, which can be used in model analysis, model testing and model comparison. We review these developments here, and present alternative derivations and shine previously unnoticed lights on them.  相似文献   
997.
Formulas that include the contribution from dipole-distributed anomalous masses represented as layers distributed in height relative to the reference ellipsoid to the gravitational field in the quadratic approximation have been derived. The relationships between the expansion coefficients of some function and its square in terms of spherical functions have been established. The contribution from the relief masses and the density jump at the Mohorovicic discontinuity is used to illustrate the results.  相似文献   
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The impedance spectra of nanocrystalline SnO2 ceramics with an average grain size d ranging from 3 to 43 nm were investigated in the frequency range 1–106 Hz at temperatures from 25 to 300°C in a dry oxygen atmosphere. Analysis of the experimental data by the graphoanalytical method made it possible to separate the contributions of grain bulk and grain boundaries to the conductivity. It is shown that the samples investigated can be arbitrarily divided into two groups with respect to the character of their conductivity. For the samples with an average grain size d < 25 nm, the charge transfer processes are almost completely determined by the grain boundaries. In samples with a larger grain size, the contribution of grain bulk to the conductivity is comparable with that of grain boundaries.  相似文献   
1000.
Nanotechnology research is booming worldwide, having an impact on multiple sectors and with a general belief that medical and biological applications will form the greatest area of expansion over the next decade, driven by an attempt to bring radical solutions to areas of unmet medical need. What is true in the USA is also being fulfilled in Europe, though generally at a significantly lower investment level, even for ’large’ capital infrastructure and interdisciplinary centres. Against this, the UK and its European partners are following the maxim ’small is beautiful’ and are attempting to identify and grow academic research and commercial businesses in areas that traditional nanotechnology developments out of engineering or physics find challenging. Thus, University College London and Imperial College, in a major joint project linked to other centres of excellence both in the UK and in the rest of Europe, are building upon their internationally competitive medical and hard-matter research activities to focus on and develop nanotechnology as a major sector of research activity. The two universities together form one of the largest centres of biomedical research outside the USA. A novel approach to commercialisation has been taken, exemplified by the establishment with government and private equity funds of a ‘Bionanotechnology Centre’ — this will act as a portal for UK industry to access specialist skills to solve issues relating to developing nanotechnology-based medical applications, for example, for environmental screening, diagnostics and therapy. This paper reviews our academic and business strategy with examples from our current research portfolio, biased towards medicine as the London Centre for Nanotechnology’s most rapidly growing area.  相似文献   
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