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| 1 | 锥面共形阵列天线盲极化DOA估计算法显示文摘由于共形载体曲率的影响,共形阵列天线中各阵元单元方向图具有不同的指向,使得共形阵列天线具有了多极化特性(Polarization Diversity),为了描述共形阵列天线的多极化特性,通常在共形阵列天线的快拍数据模型中引入阵列入射信号的极化参数,因此共形阵列天线的DOA(Direction-Of-Arrival)估计需要与阵列入射信号极化参数联合估计.本文提出了一种盲极化DOA估计算法,通过在锥面共形阵列天线中设置三对特殊子阵,利用ESPRIT(Estimationof Signal Parameters via Rotational Invariance Techniques)算法,将入射信号极化参数与二维角参数去耦合,在入射信号极化参数未知条件下实现了高分辨DOA估计,并对估计性能进行了理论分析与推导,给出了参数估计的CRB(Cramer-RaoBound),通过Monte Carlo仿真实验验证了DOA估计算法的有效性. | 齐子森 郭英 姬伟峰 王布宏 | 2009 | 电子学报2009，37，9： | 27 |
| 2 | Barometric altimetry system as virtual constellation applied in CAPS显示文摘This work describes the barometric altimetry as virtual constellation applied to the Chinese Area Positioning System (CAPS), which uses the transponders of communication satellites to transfer navigation messages to users. Barometric altimetry depends on the relationship of air pressure varying with altitude in the Earth’s atmosphere. Once the air pressure at a location is measured the site altitude can be found. This method is able to enhance and improve the availability of three-dimensional positioning. The difficulty is that the relation between barometric pressure and altitude is variable in different areas and under various weather conditions. Hence, in order to obtain higher accuracy, we need to acquire the real-time air pressure corresponding to an altimetric region’s reference height. On the other hand, the altimetry method will be applied to satellite navigation system, but the greatest difficulty lies in how to get the real-time air pressure value at the reference height in the broad areas overlaid by satellite navigation. We propose an innovational method to solve this problem. It is to collect the real-time air pressures and temperatures of the 1860 known-altitude weather observatories over China and around via satellite communication and to carry out time extrapolation forecast uniformly. To reduce data quantity, we first partition the data and encode them and then broadcast these information via navigation message to CAPS users’ receivers. Upon the interpolations being done in receivers, the reference air pressure and temperature at the receiver’s nearby place is derived. Lastly, combing with the receiver-observed real air pressure and temperature, the site’s altitude can be determined. The work is presented in the following aspects: the calculation principle, formulae, data collection, encoding, prediction, interpolation method, navigation message transmission together with errors causes and analyses. The advantages and shortcomings of the technique are discussed at the end. | AI GuoXiang SHENG PeiXuan DU JinLin ZHENG YongGuang CAI XianDe WU HaiTao HU YongHui HUA Yu LI XiaoHui | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，3： | 22 |
| 3 | On Some Nonlinear Integral and Discrete Inequalitites Related to Ou-Iang's Inequality | Yang Enhao Department of Mathematics, Jinan University, Guangzhou 510632, China | 1998 | Acta Mathematica Sinica,English Series1998，14，3： | 15 |
| 4 | A non-myopic scheduling method of radar sensors for maneuvering target tracking and radiation control显示文摘In decades,the battlefield environment is becoming more and more complex with plenty of electronic equipments.Thus,in order to improve the survivability of radar sensors and satisfy the requirement of maneuvering target tracking with a low probability of intercept,a non-myopic scheduling is proposed to minimize the radiation cost with tracking accuracy constraint.At first,the scheduling problem is formulated as a partially observable Markov decision process(POMDP).Then the tracking accuracy and radiation cost over the future finite time horizon are predicted by the posterior carmer-rao lower bound(PCRLB) and the hidden Markov model filter,respectively.Finally,the proposed scheduling is implemented efficiently by utilizing the branch and bound(B&B) pruning algorithm.Simulation results show that the performance of maneuvering target tracking was improved by the improved interacting multiple model(IMM),and the scheduler time and maximum memory consumption were significant reduced by the present B&B pruning algorithm without losing the optimal solution. | Gan-lin Shan Gong-guo Xu Cheng-lin Qiao | 2020 | Defence Technology(防务技术)2020，16，1： | 13 |
| 5 | Collapse analysis of tunnel floor in karst area based on Hoek-Brown rock media显示文摘Collapse shape of tunnel floor in Hoek-Brown rock media is investigated with the functional catastrophe theory. The stability of rock system in tunnel floor, which is determined by thickness, half collapse width, half length of cave and detaching curve, has great secure and economic significance in practical engineering. To investigate the failure mechanisms and the outline of detaching block, a reliable damage model is presumed by making reference to the limit analysis theory. The analytical solutions of detaching curve, half collapse width on tunnel floor and the critical and maximum values of collapse thickness are derived based on Hoek-Brown criterion and functional catastrophe theory. The result shows that 0.5 is a most probable condition for instability, and the shape of detaching curve is a part of parabola. It is reasonable by comparing with previous theory and analogous experiments. The effects of major factors on thickness and half collapse width are further discussed. Numerical calculations and parametric analysis are carried out to illustrate the effects of different parameters on the mechanism, which is significant to the stability analysis of tunnel floor in rock media. | 杨小礼 李正伟 刘拯安 肖海波 | 2017 | Journal of Central South University2017，24，4： | 13 |
| 6 | Eigenvalue approximation from below using non-conforming finite elements显示文摘This is a survey article about using non-conforming finite elements in solving eigenvalue problems of elliptic operators,with emphasis on obtaining lower bounds. In addition,this article also contains some new materials for eigenvalue approximations of the Laplace operator,which include:1) the proof of the fact that the non-conforming Crouzeix-Raviart element approximates eigenvalues associated with smooth eigenfunctions from below;2) the proof of the fact that the non-conforming EQ rot1 element approximates eigenvalues from below on polygonal domains that can be decomposed into rectangular elements;3) the explanation of the phenomena that numerical eigenvalues λ 1,h and λ 3,h of the non-conforming Q rot1 element approximate the true eigenvalues from below for the L-shaped domain. Finally,we list several unsolved problems. | YANG YiDu 1 ,ZHANG ZhiMin 2 & LIN FuBiao 11 School of Mathematics and Computer Science,Guizhou Normal University,Guiyang 550001,China 2 Department of Mathematics,Wayne State University,Detroit,MI 48202,USA | 2010 | Science China Mathematics2010，53，1： | 12 |
| 7 | Meta-optics and bound states in the continuum显示文摘We discuss the recent advances in meta-optics and nanophotonics associated with the physics of bound states in the continuum(BICs). Such resonant states appear due to a strong coupling between leaky modes in optical guiding structures being supported by subwavelength high-index dielectric Mieresonant nanoantennas or all-dielectric metasurfaces. First, we review briefly very recent developments in the BIC physics in application to isolated subwavelength particles. We pay a special attention to novel opportunities for nonlinear nanophotonics due to the large field enhancement inside the particle volume creating the resonant states with high-quality(high-Q) factors, the so-called quasi-BIC, that can be supported by the subwavelength particles. Second, we discuss novel applications of the BIC physics to alldielectric optical metasurfaces with broken-symmetry meta-atoms when tuning to the BIC conditions allows to enhance substantially the Q factor of the flat-optics dielectric structures. We also present the original results on nonlinear high-Q metasurfaces and predict that the frequency conversion efficiency can be boosted dramatically by smart engineering of the asymmetry parameter of dielectric metasurfaces in the vicinity of the quasi-BIC regime. | Kirill Koshelev Andrey Bogdanov Yuri Kivshar | 2019 | Science Bulletin2019，64，12： | 11 |
| 8 | An Innovative Process for Direct Reduction of Cold bound Pellets from Iron Concentrate with a Coal-based Rotary Kiln显示文摘Successfully developed an innovative process of direct reduction of cold bound pellets from iron ore concentrate with a coal based rotary kiln, in comparison with the traditional direct reduction of fired oxide pellets in coal based rotary kilns , possesses such advantages as: shorter flowsheet, lower capital investment, greater economic profit, good quality of direct reduced iron. The key technologies , such as the composite binder and corresponding feasible techniques were employed in practice. A mill utilizing this process and with an annual capacity of 50 thousand ton DRI has been put into operation. | ZHU De qing QIU Guan zhou JIANG Tao XU Jin chang | 2000 | Journal of Central South University2000，12，2： | 10 |
| 9 | Research on 3D Target Pose Tracking and Modeling显示文摘This paper tackles pose tracking and model refinement, one of the fundamental work for 3D photogrammetry. The researches belong to the videometrics, an interdisciplinewhich combines computer vision, digital image processing, photogrammetry and optical measurement. Related works are summarized briefly in this paper. This paper studies the problem of pose tracking for target with 3D model. For the target with accurate 3D model, line model based pose tracking methods are proposed for target which is rich in line features. Experimental results indicate that the proposed methods track the target pose accurately. Normal distance iterative reweighted least squares and distance image iterative least squares methods are proposed to process more general targets. This paper adopts bundle adjustment to tackle pose tracking in image sequence for target with inaccurate 3D line model. The proposed method optimizes the model line parameters and the pose parameters simultaneously. The model line orientation, position and mean angle error, mean position error of the pose are 0.3°,3.5 mm and 0.12°,20.1 mm in simulation experiments of satellite pose tracking. Line features are used to track target pose with unknown 3D model through image sequence. The model line parameters and pose parameters are optimized under the framework of SFM. In simulation experiments, the reconstructed line orientation, position error and mean angle error, mean position error of pose are 0.4°,7.5 mm and 0.16°,23.5 mm. | Yang SHANG Xiaoliang SUN Yueqiang ZHANG You LI Qifeng YU | 2019 | Journal of Geodesy and Geoinformation Science2019，2，2： | 7 |
| 10 | The smoothed finite element method (S-FEM):A framework for the design of numerical models for desired solutions显示文摘The smoothed finite element method (S-FEM) was originated by G R Liu by combining some meshfree techniques with the well-established standard finite element method (FEM). It has a family of models carefully designed with innovative types of smoothing domains. These models are found having a number of important and theoretically profound properties. This article first provides a concise and easy-to-follow presentation of key formulations used in the S-FEM. A number of important properties and unique features of S-FEM models are discussed in detail, including 1) theoretically proven softening effects;2) upper-bound solutions;3) accurate solutions and higher convergence rates;4) insensitivity to mesh distortion;5) Jacobian?free;6) volumetric-locking-free;and most importantly 7) working well with triangular and tetrahedral meshes that can be automatically generated. The S-FEM is thus ideal for automation in computations and adaptive analyses, and hence has profound impact on Al-assisted modeling and simulation. Most importantly, one can now purposely design an S-FEM model to obtain solutions with special properties as wish, meaning that S-FEM offers a framework for design numerical models with desired properties. This novel concept of numerical model demand may drastically change the landscape of modeling and simulation. Future directions of research are also provided. | Gui-Rong Liu | 2019 | Frontiers of Structural and Civil Engineering2019，13，2： | 7 |
| 11 | ON CERTAIN CLASS OF ANALYTIC FUNCTIONS DEFINED BY DIFFERENTIAL SUBORDINATION显示文摘In this paper, the new subclass Bn( ,a,A,B) of analytic functions is introduced. Its subordination relations, inclusion relations, the inequality properties and convering theorem are discussed. The results obtained in this paper are sharp, which generalize the related works of some authors and some other new results are obtained. | 刘名生 | 2002 | Acta Mathematica Scientia2002，22，3： | 6 |
| 12 | 翻译中的语用和语义关系显示文摘This paper deals with the relations of pragmatic and semantic issues arising from translation,analyses the misunderstandings of some culture bound words and expressions and then calls for the application of sociopragmatics in translation. [ | 庄恩平 | 1999 | 上海翻译1999，，4： | 6 |
| 13 | Energy analysis of rock plug thickness in karst tunnels based on non-associated flow rule and nonlinear failure criterion显示文摘The geological hazards, such as water inrush and mud outburst, are easily induced by the high water pressure caverns ahead of a karst tunnel face. Therefore, it is a pivotal issue to determine the reserved thickness of rock plug during the construction of tunnels. The limit analysis principle is employed to analyze the safe thickness from the point of energy dissipation, and the nonlinear and non-associated characteristics of geotechnical materials are both considered. On the basis of a plane failure pattern of rock plug, the expressions of detaching curve and rock plug thickness are derived. The effect of each parameter on the safe thickness of rock plug is discussed in detail, which interprets the corresponding failure scope of rock plug. The obtained results indicate that the thickness of rock plug is highly influenced by the nonlinear dilatancy coefficient and the nonlinear coefficient. The proposed method is validated by a comparison of the calculated results with those of the engineering project of the '526 karst cavern' of Yunwushan tunnel. This proposed method can provide reference basis for the design and excavation of karst tunnels in the future. | 杨子汉 张睿 许敬叔 杨小礼 | 2017 | Journal of Central South University2017，24，12： | 6 |
| 14 | 基于时频子空间投影的LOFDM系统时域相关信道估计算法显示文摘StrohmerT与Beaver S于2003年提出了适用于时频散射信道的网格正交频分复用(LOFDM,Lattice OrthogonalFrequency Division Multiplexing)系统,与传统OFDM系统相比该系统具有更高的频带利用率和更好的误码性能。LOFDM系统发送端需要自适应地调整信号的原形脉冲和其时频分布的参数,使之与信道保持匹配;而接收端则需要准确的信道估计以实现相干解调。本文针对LOFDM系统由于其信号的时频交错特性接收端无法直接利用接收信号进行时域信道估计的问题,采用一种低复杂度的等效时频子空间投影方法有效分离奇偶子载波,并在此基础上提出了一种LOFDM系统频率选择性块衰落信道条件下的时域信道估计算法。同时还对系统存在的干扰进行了分析,推导得到LOFDM系统时域信道估计算法的Cramer-Rao理论下界。仿真表明:提出的LOFDM信道估计算法不仅具有较好的均方误差性能,而且近似达到理想信道估计的误符号率性能。 | 高猛 沈越泓 许魁 | 2011 | 信号处理2011，27，1： | 5 |
| 15 | Chloride transference during electrochemical chloride extraction process显示文摘Chemical titration method and lab-made chloride probes were jointly adopted to investigate the effects of water-to-cement (W/C) ratio and the impressed current density on chloride transport for cement-based materials during electrochemical chloride extraction (ECE) process.The dissolution of bound chlorides and the effect of current density on dissolution were analyzed.The variations of chloride concentration at different depths and the chloride transference process were monitored.Test results show that W/C ratios adopted have slight influence on chloride extraction,while chloride extraction efficiency is mainly determined by the impressed current density.During ECE process a portion of bound chloride ions dissolved and the amount of bound chlorides released is directly proportional to current density. | YAO Wu & ZHAO Zheng Key Laboratory of Advanced Civil Engineering Materials (Tongji University),Ministry of Education of China,Shanghai 200092,China | 2010 | Science China(Technological Sciences)2010，53，6： | 5 |
| 16 | GENERALIZATIONS OF PACHPATTE'S INTEGRAL AND DISCRETE INEQUALITIES显示文摘Some new integral and discrete inequalities with power nonlinearity are established. Two recent results of B.G. Pachpatte are improved by some particularcorollaries of our results. Application examples are also indicated. | 杨恩浩 | 1997 | Annals of Differential Equations1997，13，2： | 5 |
| 17 | UPPER BOUND METHOD FOR SINTERED POWDER MATERIALS IN PLANE STRAIN显示文摘UPPERBOUNDMETHODFORSINTEREDPOWDERMATERIALSINPLANESTRAINUPPERBOUNDMETHODFORSINTEREDPOWDERMATERIALSINPLANESTRAIN￥Hua,LinZhao,Zh... | Hua, Lin Zhao, Zhongzhi | 1994 | 中国有色金属学会会刊:英文版1994，4，2： | 4 |
| 18 | Distribution system state estimation: an overview of recent developments显示文摘In the envisioned smart grid, high penetration of uncertain renewables, unpredictable participation of(industrial) customers, and purposeful manipulation of smart meter readings, all highlight the need for accurate,fast, and robust power system state estimation(PSSE). Nonetheless, most real-time data available in the current and upcoming transmission/distribution systems are nonlinear in power system states(i.e., nodal voltage phasors).Scalable approaches to dealing with PSSE tasks undergo a paradigm shift toward addressing the unique modeling and computational challenges associated with those nonlinear measurements. In this study, we provide a contemporary overview of PSSE and describe the current state of the art in the nonlinear weighted least-squares and least-absolutevalue PSSE. To benchmark the performance of unbiased estimators, the Cramér-Rao lower bound is developed.Accounting for cyber attacks, new corruption models are introduced, and robust PSSE approaches are outlined as well. Finally, distribution system state estimation is discussed along with its current challenges. Simulation tests corroborate the effectiveness of the developed algorithms as well as the practical merits of the theory. | Gang WANG Georgios B.GIANNAKIS Jie CHEN Jian SUN | 2019 | Frontiers of Information Technology & Electronic Engineering2019，20，1： | 4 |
| 19 | Entanglement capacity of two-qubit unitary operator for rank two mixed states显示文摘The entanglement capacity of two-qubit unitary operator acting on rank two mixed states in concurrence is discussed. The condition of perfect entangler is the same as that acting on pure states and the entanglement capacity is the mixing parameter v1. For non-perfect entangler,the upper and lower bound of the entanglement ca-pacity are given. | DI YaoMin & LIU Li Department of Physics,Xuzhou Normal University,Xuzhou 221116,China | 2007 | Science China(Physics,Mechanics & Astronomy)2007，50，6： | 4 |
| 20 | 结合局部理想点搜索的多目标粒子群算法显示文摘提出了一种结合约束二次逼近优化(bound optimization by quadratic approximation,BOBYQA)搜索算法的理想点法对非支配解进行局部优化的混合多目标粒子群方法(local search with multiobjective particle swarm optimization,LSMOPSO),以提高多目标粒子群算法的收敛性能和非支配解集的精度与多样性。LSMOPSO算法使用拥挤距离选择领导粒子组成领导粒子集,并对其进行理想点局部搜索;分析比较了全局理想点和局部理想点对算法性能的影响,提出基于局部理想点的局部搜索策略;在粒子的设计空间的多个维度上引入均匀变异操作,降低算法陷入局部最优的可能。基本测试函数的求解结果表明,算法的收敛速度很快,而且搜索到的非支配解集的精度高、多样性好。 | 程诗信 詹浩 舒兆鑫 | 2015 | 系统工程与电子技术2015，37，10： | 3 |
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