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Science china(information Sciences) 2011年第1期54卷 146-152页

作者： YANG TianChi1,YU ChaoQun2,WANG TianPeng1 & JIN Liang1 1National Digital Switching System engineering and Technological Research Center, zhengzhou 450002,china 2surveying and mapping college of information engineering university, zhengzhou 450002,china National Digital Switching System engineering and Technological Research Center surveying and mapping college of information engineering university

A target position can be estimated using position information from scattered signals in the nonline-of-sight propagation environment in a single observer location *** is always an error in the final estimated result of the position obtained using scatter signals because measurement noise is *** reduce the total error of the system,we propose a method of converting the problem of optimizing location into a one of solving the extremes of the *** the problem of how to solve the extremes of the constraints is converted into an unconstrained problem by using the constrained total least squares(CTLS) ***,the Newton iteration method is used to obtain the optimized *** results also verify the capability of this method.

关键词： scatter position disturbing VOCTLS single observer location Newton iteration

A new learning statistic for adaptive filter based on predicted residuals

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Progress in Natural Science:Materials International 2006年第8期16卷 833-837页

作者： YANG Yuanxi and GAO Weiguang (Xi'an Research Institute of surveying and mapping, Xi'an710054, china Institute of surveying and mapping, university of information engineering, zhengzhou 450052, china) Xi''an Research Institute of surveying and mapping Xi''an 710054 China. Institute of surveying and mapping University of Information Engineering Zhengzhou 450052 China

A key problem for an adaptive filter is to establish a suitable adaptive factor for balancing the contributions of the measurements and the predicted state information from some kinematic models. The reasonable adaptive factor needs a reliable learning statistics to judge the state kinematic model errors. After analyzing the existing two kinds of learning statistics based on the state discrepancy and variance component ratio, a new learning statistic based on predicted residuals is set up, which is different from the exiting learning statistics. The new learning statistic does not need to estimate the kinemetic state parameters before the filtering process, Of course, it does not need necessary measurements to estimate state parameters for all observation epochs. The new learning statistic can be applied together with the learning factor constructed by the state discrepancy. The advantages and shortcomings of the new learning factor are analyzed, and an example is given.

关键词： adaptive factor adaptive filter kinematic model predicted residual.

Local and Global Character Sums

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Acta Mathematica Sinica,English Series 2000年第3期16卷 535-540页

作者： Chunlei Liu zhengzhou university of information engineering,zhengzhou 450002,P.R.china zhengzhou university of information engineering Zhengzhou 450002 P. R. China

Hua’s estimate is established for character sums in a number field.A relationship between liftings of a character sum in a local field is also studied.

关键词： Character sum Exponential sum

Array errors active calibration algorithm based on instrumental sensors

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Science china(information Sciences) 2011年第7期54卷 1500-1511页

作者： WANG Ding & WU Ying Institute of information engineering,information engineering university,zhengzhou 450002,china Institute of information engineering Information Engineering University

The array mutual coupling,gain-phase errors and sensor position errors would significantly degrade the performance of high-resolution direction of arrival (DOA) estimation *** at the combined influences of the above three array errors,a kind of active calibration algorithm is presented with the help of instrumental sensors in this ***,the integrated effects of the three array errors are shown to be equivalent to angularly dependent gain-phase ***,a non-linear least square (LS) optimization model for the three array errors is established through an auto-calibration algorithm using auxiliary sensors,and the corresponding resolving algorithms of the LS optimization problem are given according to the different models of array errors ***,the parameter estimation uniqueness of the proposed algorithms is analyzed in detail and an improvement strategy is ***,the effectiveness of the novel algorithm is validated by simulations.

关键词： array calibration array errors mutual coupling effect gain-phase errors sensor position errors instrumental sensors

Constructing quantum error correcting code via logic function

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Science china(information Sciences) 2010年第3期53卷 515-523页

作者： ZHONG ShuQin, MA Zhi & XU YaJie zhengzhou Institute of information engineering, university of information engineering of china, zhengzhou 450002, china zhengzhou Institute of information engineering University of Information Engineering of China

We present a systematic way to construct p-ary quantum error correcting codes using logic functions. As a consequence, for a given function with APC distance d′ 2, we can construct quantum codes with parameters ((n, K, d))p and gain a lower bound of K for all 2 d d′. The basic states of the constructed quantum codes can be stated and the sufficient conditions for saturating quantum Singleton bound are also discussed. We give quantum codes [[5, 1, 3]]p with p prime, [[6, 0, 4]], [[6, 2, 3]]p with p > 2 prime and [[2n, 2n - 2, 2]] as examples constructed in this way.

关键词： quantum error-correcting code logic states APC distance

Array errors active calibration algorithm and its improvement

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Science china(information Sciences) 2010年第5期53卷 1016-1033页

作者： WANG Ding & WU Ying Institute of information engineering, information engineering university, zhengzhou 450002, china Institute of information engineering Information Engineering University

The combined effects of mutual coupling, gain and phase errors, and sensor position errors have great negative impact on the direction-finding performance of the MUSIC algorithm. This paper investigates the calibration of the array errors induced by the three errors. Based on the array errors calibration algorithm (algorithm 1) presented by See, two improved array error-calibrating algorithms are presented. One (algorithm 2) uses the sparseness of mutual coupling matrix, and the other (algorithm 3) utilizes more special structures of mutual coupling matrix. Although the three algorithms have the same computation mode and theoretical framework, the latter two algorithms have much higher precision than the former one, as more properties of mutual coupling matrix are utilized in the two algorithms, and if the array manifold is uniform linear array or uniform circular array, algorithm 3 could have more obvious advantages. On the other hand, the three algorithms can be generalized to the situation when the calibration source azimuths have deviations. The three extended algorithms can not only calibrate the array errors, but also offset the deviations of calibration source azimuths simultaneously. Finally, the performances of the three algorithms are compared both in the absence and presence of the deviations of calibration source azimuths. Many simulation experiments demonstrate that the estimation precision of array errors can be obviously improved if more properties of mutual coupling matrix are effectively used.

关键词： array calibration mutual coupling gain and phase error sensor position errors complex symmetric banded Toeplitz matrix complex symmetric circular matrix sparse matrix

A relationship between the nonexistence of generalized bent functions and class groups

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Science china Mathematics 2010年第1期53卷 213-222页

作者： LIU FengMei 1,& YUE Qin 21 Department of information Research,college of information engineering,information engineering university,zhengzhou 450002,china 2 Department of Mathematics,Nanjing university of Aeronautics and Astronautics,Nanjing 210016,china Department of information Research College of Information Engineering Information Engineering University Zhengzhou China Department of Mathematics Nanjing University of Aeronautics and Astronautics Nanjing China

A new result on the nonexistence of generalized bent functions is presented by using properties of the decomposition law of primes in cyclotomic fields and properties of solutions of some Diophantine equations. At the same time,a method is given which can be used to simplify the known results. Then we give the bounds and the meaning in algebraic number theory of the parameters in our results.

关键词： generalized bent function integral basis class group genus theory

Digital close-range photogrammetric application to small-scale physical simulation experiment

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中国有色金属学会会刊：英文版 2011年第S3期21卷 681-685页

作者： LI Chun-yi1, CUI Xi-min2, YU Yi-ju3 1. School of surveying and Landing information engineering, Henan Polytechnic university, Jiaozuo 454003, china 2. college of Geoscience and surveying engineering, china university of Mining and Technology, Beijing 100083, china 3. surveying and mapping Press, Beijing 100045, china School of surveying and Landing information engineering Henan Polytechnic University Jiaozuo 454003 China college of Geoscience and surveying engineering China University of Mining and Technology Beijing 100083 China surveying and mapping Press Beijing 100045 China

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.131 mm and vertical direction is ±0.192 mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

关键词： close-range photogrammetric physical simulation light-rays adjustment surveying precision subsidence factor

Fracture analysis of a functionally graded interfacial zone between two dissimilar homogeneous materials

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 540-552页

作者： CHENG Zhanqi1,2 & ZHONG Zheng1 1. School of Aerospace engineering and Applied mechanics, Tongji university, Shanghai 200092, china 2. college of Civil engineering, zhengzhou university, zhengzhou 450002, china School of Aerospace engineering and Applied mechanics Tongji University Shanghai China college of Civil engineering Zhengzhou University Zhengzhou China

In this paper the plane elasticity problem for a functionally graded interfacial zone containing a crack between two dissimilar homogeneous materials has been considered. It is assumed that in the interfacial zone the reciprocal of the shear modulus is a linear function of the coordinate, while Possion’s ratio keeps constant. By utilizing the Fourier transformation technique and the transfer matrix method, the mixed boundary problem is reduced to a system of singular integral equations that are solved numerically. The influences of the geometric parameters and the graded parameter on the stress intensity factors are investigated. The numerical results show that the graded parameters, the thickness of interfacial zone, the crack size and location have significant effects on the stress intensity factors.

关键词： functionally graded material interfacial zone fracture stress intensity factor

A NEW METHOD OF FREQUENCY-HOPPING(FH) SIGNAL DETECTION

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Journal of Electronics(china) 2011年第4期28卷 468-473页

作者： Zeng Yu Liu Xueqian Li Ou(information and engineering university,information and engineering Institute,zhengzhou 450002,china) information and engineering Institute Information and Engineering University Zhengzhou China zhengzhou China

A new Frequency-Hopping(FH) signal detection method is *** from pre-vious methods which need to monitor the total band,it can monitor part of the band and decrease the range of the *** to this method,a new detection model is set and the computation formulas of the detection probability and false-alarm probability are *** parameters of a VHF radio are used to prove the validity of the *** results show that this method can de-crease the range of the bandwidth and detect the FH signal with some penalty on the SNR and signal loss.

关键词： Frequency-Hopping(FH) Detection Monitor Interception Channelized radiometer