Due to the complexity of indoor wireless environment, indoor position is more difficult than other location technologies in wireless sensor network, and how to improve accuracy of location is one of the key research p...
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This paper is to predict economic development based on wavelet least squares support vector machine algorithm. The same as support vector machine, least squares support vector machine employs the principle of structur...
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A whisper intelligibility enhancement method was proposed based on the Real-valued Discrete Gabor Transform (RDGT) in the joint time frequency domain where the RDGT can change the density of the spectrum through the o...
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Finding correspondences between two related feature point sets is a basic task in computer vision and pattern recognition. In this paper, we present a novel method for point pattern matching via spectral graph analysi...
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Shrub encroachment has been a wide phenomenon across the arid and semi-arid grasslands in Inner Mongolia, China. Although numerous studies have investigated the effect of this phenomenon on community composition, ecos...
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Shrub encroachment has been a wide phenomenon across the arid and semi-arid grasslands in Inner Mongolia, China. Although numerous studies have investigated the effect of this phenomenon on community composition, ecosystem structure, and nutrient cycling, reports on the distribution patterns of shrub encroachment are limited. A recent development in satellite remote sensing enables accurate assessment of shrub distribution and its dynamics at large scales. In this paper, the combined ground survey in Xianghuangqi, four satellite images (with spatial resolution of 5.8 m) of ZY-3, covering nearly the whole area and taken between July and August in 2013, were used to identify the shrub distribution in this region. It should be noted that the shrub here indicated the shrub-grass mosaic due to the mixed pixel effect, and the identification was weak when the coverage of shrub was on low levels. The NDVI threshold method was first used to extract the vegetation coverage area, and then three traditional pixel-oriented methods (Support vector machine, Maximum likelihood and Mahalanobis distance), compared with the object-oriented method, were used for the classification of images. Object-oriented method is different from the traditional one, in that the classification is not based on the spectral characteristics of individual pixel, but relies on the image object with spatial texture and shape and size characteristics. Ground survey data were used to compare the accuracy level of these methods. It indicated that the shrub recognition accuracy by using support vector machine algorithm is the highest among the three pixel-oriented methods, with higher producer accuracy and user accuracy than the other two algorithms. Furthermore, the overall classification accuracy of this algorithm is 81.15% higher than that of the maximum likelihood (73.33%) and the Mahalanobis distance (61.77%). However, the overall recognition accuracy by using the object-oriented approach (combined scale
This paper presents a novel method that integrates the Algebraic Connectivity Strength of Point(ACSP) and Scoring Criteria to identify genes associated with tumor ***,for each gene,the ACSP is used to identify reliabl...
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This paper presents a novel method that integrates the Algebraic Connectivity Strength of Point(ACSP) and Scoring Criteria to identify genes associated with tumor ***,for each gene,the ACSP is used to identify reliable expression levels of the gene in all the *** informative genes are then selected using Scoring Criteria based on these reliable expression ***,the Support Vector Machine(SVM) classifier is used to classify the two datasets of gene expression *** results show that the informative genes selected by the proposed method have higher credibility than those selected by Scoring Criteria alone.
With the developing of low-power wireless techniques such as the micro-sensors, analog and digital electronic technology and radio frequency technology, different kinds of wireless sensor networks are widely used in t...
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With the developing of low-power wireless techniques such as the micro-sensors, analog and digital electronic technology and radio frequency technology, different kinds of wireless sensor networks are widely used in the field of military, civil, medical and so on. However, in practical applications, the low-power consumption and long-distance have not been well achieved in the wireless sensor networks. In this paper, a low-power and long-distance system based on wireless sensor networks is proposed. The system model consists of two parts: the hardware includes server node, client nodes and ARM boards. The software mainly handle the analysis and construction of the communication frame as well as data analysis and processing and then the data information is processed to report to the server. We can reduce the energy consumption and increase the transmission distance by the combined application of hardware and software. The system can be used in different occasions and does have a grand application prospect.
Summary form only given. Strong light-atom interaction is at the heart of atomic, molecular and optical physics; and is also important to quantum optics, quantum computing, nuclear magnetic resonance and laser. When a...
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Summary form only given. Strong light-atom interaction is at the heart of atomic, molecular and optical physics; and is also important to quantum optics, quantum computing, nuclear magnetic resonance and laser. When an atom (or two-level system) is illuminated by a coherent beam of photons, it will cyclically absorb photons and re-emit them by stimulated emission, which is called Rabi oscillation. Here we developed a semiclassical framework to model the phenomenon via a self-consistent solution to Maxwell-Schrödinger equations. Different from Maxwell-Bloch equations, the wave function of the atom replacing for the density matrix nonlinearly interacts with the magnetic vector potential under coulomb gauge condition. A well-posed time evolution system derived from light-atom Hamiltonian is numerically solved by finite-difference time-domain method. The developed semiclassical Maxwell-Schrödinger framework could be generalized to model light-exciton interaction in semiconductor nanostructures.
Due to the uncertainty principle, the traditional single window based discrete Gabor transform has a fixed joint time-frequency resolution. In order to improve the joint time-frequency resolution of the traditional di...
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