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We manipulate the pore size of nanoporous polymeric photonic crystals using phase change between water and ice, demonstrating accurate post-manipulation of reflection resonances and thereby providing an approach to address grand challenges in nanomanufacturing and materials engineering.
Ballistic reentry target trajectory tracking is an important application of nonlinear filtering problems. Under non-Gaussian noise, Standard Particle Filter (SPF) and many revised PFs (i.e. MSRCQPF) can obtain good results. However, the two algorithms may meet some defects respectively, such as particle degradation, large computational complexity and so on. This paper propose a multimode sampling...
This research proposed a TCM FS Ontology using FS-associated information retrieved from ancient Chinese medical texts. To standardize the process, we rigorously followed the 7-steps-approach proposed by Standard University. Besides, the establishing of axioms constraining the relationships between concepts may provide reference for the construction of knowledge base in future studies.
Recently, 802.11ah with restricted access window for collision attenuation has been proposed for Internet of Things (IoT) applications. Random grouping of nodes in different access window is utilized to reduce the hidden node collision probability. However, when the coverage area of the sink node is large, the occurrence probability of hidden node problem is still high and severely impacts the system...
This paper researches on millimeter-wave (mm-wave) channel estimation based on interference cancellation (IC) and DOA (Direction of Angles) estimation in hybrid massive MIMO systems. According to the ray-tracing model, the mm-wave channel estimation problem can be solved by converting into the estimation of parameters including the angles of departure (AOD), the angles of arrival (AOA) and the path...
Exponential Mixture Densities (EMDs) is increasingly popular as a suboptimal distributed fusion technique that avoids calculating the common information between different nodes. However, there exists some concerns about the EMDs because it fuses the cluttered posterior density as a whole, which contains plenty of components of little physical significance. Thus, it becomes intractable and computation...
The radar cross section (RCS) reduction technique for dipole antenna using checkerboard surface is investigated. The checkerboard surface is used as ground of dipole antenna instead of a metal ground. In the operating frequency band of the antenna, the checkerboard surface can reflect electromagnetic wave nearly in phase, thus the radiation performance of the antenna is not degraded. However, for...
A method that combines high-order triangular element and PO method over electrically large conducting targets illuminated by a complex source beam (CSB) is developed in this paper. High-order triangular element is used to subdivide the surface of target and PO result is obtained to investigate the scattering properties. This method has the merit of being very accurate and efficient, and its computation...
Phase weighting at the subarray level alone causes grating lobes (GLs) in the far field pattern. In this paper, a technique for reducing GLs in phased arrays with regular subarray architectures is proposed. Two measures are used in this method. They are: (1) integrating a power divider with phase difference among output ports for each subarray, which controls the each subarray pattern has a different...
In this paper, the implementation of the sources for scattering and radiation of the discontinuous Galerkin time domain method (DGTD) are presented. Based on formulations of the DGTD method, the sources implementation procedure is given, including the incident plane wave generated for scattering and the modeling of a coaxial port feed for antenna radiation. Numerical examples of PEC almond scattering...
We demonstrate that the scattering patterns of a phased array can be controlled with switches loaded annular slot elements. When these switches are off, the elements can radiate efficiently as annular slot antennas. On the other hand, when these switches are on, the incident wave can be reflected by these elements to a desired angle, determined by the locations of the switches.
Ensemble methods use multiple classifiers to achieve better decisions than could be achieved using any of the constituent classifiers alone. However, both theoretical and experimental evidence have shown that very large ensembles are not necessarily superior, and small ensembles can often achieve better results. In this paper, we show how to combine a set of weak classifiers into a robust ensemble...
In the era of information explosion, the full-text search engine must index vast amounts of data as soon as possible to provide the best retrieval service. This paper firstly analyzes problems of the traditional stand-alone indexing, and how to solve them by distributed and parallel indexing. Then proposed a distributed indexing algorithm based on the Map/Reduce, which changed the structure of map...
Target tracking is a hot topic for unmanned aerial vehicle surveillance. Recently, the novel random sample consensus (RANSAC) algorithm shows a good tracking performance in dense clutter environment. However, the heavy computational burden limits the usage for unmanned aerial vehicle (UAV). In this paper, a density-based recursive random sample consensus (DBR-RANSAC) algorithm is proposed, which utilizes...
Cryptographic technology is the basic and core technology to guarantee network and information security. It is imperative to standardize cryptographic algorithms. Cryptographic algorithm test is the most important research content of cryptographic normalization. Symmetric cryptographic algorithms are the most widely studied and applied. So it has the practical value to normalize the symmetric cryptographic...
Video streaming over networks has grown rapidly in recent years. Increasing focus has gradually turned from Quality of Service (QoS) awareness to user Quality of Experience (QoE) awareness. In this paper, we propose a unified QoE prediction framework for HEVC encoded video streaming. Firstly, the impact of network impairment on QoE is modelled by packet loss rate. Secondly, features of HEVC encoding...
In recent years, accidents of urban road collapsing occur frequently, which not only cause considerable economic losses, but also the casualties. For the various problems and potential security risks brought by urban road collapsing, this paper analyzes the factors of urban road collapsing and a new warning method based on dynamic tracking is put forward. And a warning model of hazard grade of urban...
A robust disturbance rejection guidance law for autonomous rendezvous with non-cooperative target is studied using generalized super-twisting algorithm (GSTA) and homogeneous high order sliding mode observer (HHOSMO). The proposed method is able to ensure a service spacecraft subject to modeling uncertainties, external disturbances and actuator/thruster failures accomplishes the rendezvous mission...
The development of high power and compact size semiconductor packages lead to the challenge in the need of high thermal dissipation design. For package level thermal solution, metal (especially copper) heat spreader and metal/metal-oxide filler thermal interface material are widely adopted. However, the thermal performance of packages is limited by isotropic conductive behavior of most of these materials...
Quantitative imaging biomarkers identification has become a powerful tool for predictive diagnosis given increasingly available clinical imaging data. In parallel, molecular profiles have been well documented in non-small cell lung cancers (NSCLCs). However, there has been limited studies on leveraging the two major sources for improving lung cancer computer-aided diagnosis. In this paper, we investigate...
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