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81.
82.
In this paper, a novel algorithm for the detection and localization of the face and eyes in thermal images is presented, particularly the temperature measurement of the human body by measuring the eye corner (inner canthus) temperature. The algorithm uses a combination of the template-matching, knowledge-based and morphological methods, particularly the modified Randomized Hough Transform (RHT) in the localization process, also growing segmentation to increase accuracy of the localization algorithm. In many solutions, the localization of the face and/or eyes is made by manual selection of the regions of the face and eyes and then the average temperature in the region is measured. The paper also discusses experimental studies and the results, which allowed the evaluation of the effectiveness of the developed algorithm. The standardization of measurement, necessary for proper temperature measurement with the use of infrared thermal imaging, are also presented. 相似文献
83.
针对基于移动预测定位的SLMP算法在定位中没有参考其他节点的移动预测信息,提出了基于洋流态势的移动预测CMP算法,算法在移动定位的过程中,考虑水流影响,结合了前驱节点的移动预测信息及其他信息来完成预测.大量的仿真结果表明,CMP算法在定位覆盖度及平均通信代价方面有良好的性能,也表明了CMP算法能够更好的适应于大规模水下移动环境. 相似文献
84.
We introduce a global wave front set suitable for the analysis of tempered ultradistributions of quasi-analytic Gelfand–Shilov type. We study the transformation properties of the wave front set and use them to give microlocal existence results for pullbacks and products. We further study quasi-analytic microlocality for classes of localization and ultradifferential operators, and prove microellipticity for differential operators with polynomial coefficients. 相似文献
85.
Random fluctuations of the shot-noise power in disordered graphene nanoribbons are studied. In particular, we calculate the distribution of the shot noise of nanoribbons with zigzag and armchair edge terminations. We show that the shot noise statistics is different for each type of these two graphene structures, which is a consequence of the presence of different electron localizations: while in zigzag nanoribbons electronic edge states are Anderson localized, in armchair nanoribbons edge states are absent, but electrons are anomalously localized. Our analytical results are verified by tight binding numerical simulations with random hopping elements, i.e., off diagonal disorder, which preserves the symmetry of the graphene sublattices. 相似文献
86.
We evaluate the spin polarization (Edelstein or inverse spin galvanic effect) and the spin Hall current induced by an applied electric field by including the weak localization corrections for a two-dimensional electron gas. We show that the weak localization effects yield logarithmic corrections to both the spin polarization conductivity relating the spin polarization and the electric field and to the spin Hall angle relating the spin and charge currents. The renormalization of both the spin polarization conductivity and the spin Hall angle combine to produce a zero correction to the total spin Hall conductivity as required by an exact identity. Suggestions for the experimental observation of the effect are given. 相似文献
87.
Pinggui Yi Zhengjun Liu Zhaoxu Wang Xianyong Yu Jiming Zhou Bo Hou Qingzhong Li 《International journal of quantum chemistry》2013,113(9):1316-1324
Density functional theory calculations were performed at the B3LYP/6‐311++G(d,p) level to systematically explore the geometrical multiplicity and binding strength for the complexes formed by alkaline and alkaline earth metal cations, viz. Li+, Na+, K+, Be2+, Mg2+, and Ca2+ (Mn+, hereinafter), with 2‐(3′‐hydroxy‐2′‐pyridyl)benzoxazole. A total of 60 initial structures were designed and optimized, of which 51 optimized structures were found, which could be divided into two different types: monodentate complexes and bidentate complexes. In the cation‐heteroatom complex, bidentate binding is generally stronger than monodentate binding, and of which the bidentate binding with five‐membered ring structure has the strongest interaction. Energy decomposition revealed that the total binding energies mainly come from electrostatic interaction for alkaline metal ion complexes and orbital interaction energy for alkaline earth metal ion complex. In addition, the electron localization function analysis show that only the Be? O and Be? N bond are covalent character, and others are ionic character. © 2012 Wiley Periodicals, Inc. 相似文献
88.
Copolymers of aniline with p‐toluidine were synthesized for different molar ratios of the respective monomers in acid medium. The electrical conductivity, charge transport and spectral characteristics upon incorporation of p‐toluidine units into the polyaniline backbone were investigated. The electrical conductivity of the copolymers showed frequency dependence which became more prominent with an increase in the number of p‐toluidine units in the polyaniline backbone. A direct relationship between the frequency dependence and electron localization was observed in the copolymers. Electronic spectra showed blue shifts in the π→π*and benzenoid→quinoid transitions revealing a decrease in the extent of conjugation in the copolymers. The protonated forms of the copolymers were soluble in DMSO giving polaron band around 400 nm. The decrease in electrical conductivity was attributed to the greater electron localizations as revealed from the broader ESR signals. Temperature dependence of electrical conductivity showed that charge transport was mainly through variable range hopping though a mixed conduction behavior was observed at higher temperature range. 相似文献
89.
《Journal of computational chemistry》2017,38(4):204-210
This work addresses the decomposition of the Electron Localization Function (ELF) into partial density contributions using an appealing split of kinetic energy densities. Regarding the degree of the electron localization, the relationship between ELF and its usual spin‐polarized formula is discussed. A new polarized ELF formula, built from any subsystems of the density, and a localization function, quantifying the measure of electron localization for only a subpart of the total system are introduced. The methodology appears tailored to describe the electron localization in bonding patterns of subsystems, such as the local nucleophilic character. Beyond these striking examples, this work opens up opportunities to describe any electronic properties that depend only on subparts of the density in atoms, molecules, or solids. © 2016 Wiley Periodicals, Inc. 相似文献
90.
Fourth-order cumulant is one of most widely used high-order cumulant for direction of arrival (DOA) estimation due to its ability of expanding the virtual array aperture as well as suppressing Gaussian noise. To address the two-dimensional (2D) DOA estimation problem, we propose a modified MUSIC scheme for uniform circular array (UCA) in this paper. Firstly, the fourth-order cumulant of UCA is considered to construct a new propagator, resulting in the elimination of a priori knowledge of the number of signals. Secondly, the UCA is transformed by beamspace transformation, reducing the time computational complexity of the algorithm since the two-dimensional grid search and singular value decomposition are avoided. And finally a low-rank recovery algorithm is adopted to improve the accuracy regarding the limited snapshots scenario. The numerical simulations validate the superiority of the proposed method. 相似文献