The complex problems usually have netted structure, namely netted problems. The generally solving methods are based on sequence-searching or tree-searching of this kind of problems. But the structure of netted problem...
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In this paper, we constructed the architecture of mobile heterogeneous sensor network by introducing user equipments (UEs) in static wireless sensor network. We analyzed the failure of traditional static clustering al...
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In this work, we study the fractal and multifractal properties of a family of fractal networks introduced by Gallos et al (2007 Proc. Nat. Acad. Sci. USA 104 7746). In this fractal network model, there is a parameter ...
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On the basis of the method of moments and segments sinusoidal basis functions, the impedance matrix of plasmonic nano-rod antennas can be obtained by solving the Green's function of the discretized current nodes i...
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On the basis of the method of moments and segments sinusoidal basis functions, the impedance matrix of plasmonic nano-rod antennas can be obtained by solving the Green's function of the discretized current nodes in closed form formulations. Compared to the method of moments with different basis functions, this method can be utilized for reducing the size of matrix equations. The simulated results show that the polarization current and scattered fields can be computed accurately by employing a small-size matrix, which leads to a fast analysis for the scattering characteristic and resonant modes of nano-rod. The accuracy of the method was successfully demonstrated by comparing the simulated results with finite difference time domain technique, which is more time-consuming than the present method. Especially when dealing with the oblique incidence problem, the advantages become more apparently. The method is effective for the calculated models in this paper, and provides a fast and efficient electromagnetic analysis way for other nano-rod antennas and nanotube devices in different shapes when doing their scattering characteristics simulation.
The improvement of the efficiency of spontaneous emission will give great help to the research and manufacture of optoelectronic devices such as single photon resource. The local density of elestromagnetic states was ...
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The improvement of the efficiency of spontaneous emission will give great help to the research and manufacture of optoelectronic devices such as single photon resource. The local density of elestromagnetic states was calculated which is represented by the electric dyadic Green's function through the finite-difference frequency-domain method, the local density of states and the spontaneous emission rate in different metal materials, structures and wavelengths were analyzed, and the intrinsic physical mechanism was explored. The results show that the spontaneous emission rate of atoms can be greatly enhanced when surface plasmon polariton couple to the emiter, and different structure and the refractive indices of materials have different improvement of spontaneous emission rate. This research can provide important reference for the manufacture and optimization of optoelectronic devices.
Using the new inhomogeneous medium interface equivalent parameter scheme combined with the finite-difference frequency-domain method, numerical analysis on mechanism of the optical properties of the thin-film solar ce...
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Using the new inhomogeneous medium interface equivalent parameter scheme combined with the finite-difference frequency-domain method, numerical analysis on mechanism of the optical properties of the thin-film solar cell with periodic structure was presented. The plasmon resonance condition was used to study the reflection, the transmission, the absorption characteristics, and the distribution of total field. In the low frequence point, the enhancement of the total field is obviousat the interface of the medium layer and the Ag layer, and the absorption increases significantly. Furthermore, the relationship between the enhancement factor, the structure, the incident wavelength and the angle of incidence was discussed, and its intrinsic physical mechanism was also analyzed. The enhancement factor is very large at low frequency and increases with the enhancement of the incident angle. The results show that the enhancement factor can increaseto 5.7. The proposed research work can provide a relevant theory and technical reference for the design and optimization of the actual organic thin-film solar cells.
Based on protein molecular dynamics, we investigate the fractal properties of energy, pressure and volume time series using the multifractal detrended fluctuation analysis (MF-DFA) and the topological and fractal prop...
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Based on protein molecular dynamics, we investigate the fractal properties of energy, pressure and volume time series using the multifractal detrended fluctuation analysis (MF-DFA) and the topological and fractal properties of their converted horizontal visibility graphs (HVGs). The energy parameters of protein dynamics we considered are bonded potential, angle potential, dihedral potential, improper potential, kinetic energy, Van der Waals potential, electrostatic potential, total energy and potential energy. The shape of the h ( q ) curves from MF-DFA indicates that these time series are multifractal. The numerical values of the exponent h ( 2 ) of MF-DFA show that the series of total energy and potential energy are non-stationary and anti-persistent; the other time series are stationary and persistent apart from series of pressure (with H ≈ 0.5 indicating the absence of long-range correlation). The degree distributions of their converted HVGs show that these networks are exponential. The results of fractal analysis show that fractality exists in these converted HVGs. For each energy, pressure or volume parameter, it is found that the values of h ( 2 ) of MF-DFA on the time series, exponent λ of the exponential degree distribution and fractal dimension d B of their converted HVGs do not change much for different proteins (indicating some universality). We also found that after taking average over all proteins, there is a linear relationship between 〈 h ( 2 ) 〉 (from MF-DFA on time series) and 〈 d B 〉 of the converted HVGs for different energy, pressure and volume.
Face recognition is one of typical biometric identification method, which has a great prospect in secure authentication system, file management, human-computer interaction and social security. This paper proposes gray...
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ISBN:
(纸本)9781479951529
Face recognition is one of typical biometric identification method, which has a great prospect in secure authentication system, file management, human-computer interaction and social security. This paper proposes gray-scale characteristics and creates facial templates to recognize faces method based on a given number of samples. Firstly, it selects the method of building template according to the number of samples to create the facial template image; then, it will compare the difference of first-order edge entropy between recognition image and the template image and find the best match result; finally, the recognition result is output. Experimental results show that the proposed algorithm has good recognition effect on face recognition under non-constraint conditions.
A new uniplanar printed PIFA with a coupled-feed structure for LTE/WWAN operation is proposed. The PIFA consists of a coupled-feed loop structure and two separated radiators which are able to generate additional bands...
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A new uniplanar printed PIFA with a coupled-feed structure for LTE/WWAN operation is proposed. The PIFA consists of a coupled-feed loop structure and two separated radiators which are able to generate additional bands for the operation. The loop antenna path and the longer radiator can produce a dualresonance generating the required lower band exactly, while three wide bands contributed by the loop path, the loop path with the longer radiator and the loop path with the shorter radiator can form an operating band to cover the(1710–2690 MHz) band. Because of the small size of only 14×70 mm2, the antenna which can cover the required eight bands is therefore very suitable for the modern Ultra-thin laptops.
Vehicular Ad Hoc Networks (VANETs) can provide participants with security services and entertainment information during the driving. To guarantee correct and smooth operations of VANETs, it is necessary to achieve eff...
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