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A User Differential Range Error Calculating Algorithm Based on analytic method

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Chinese Journal of Aeronautics 2011年第6期24卷 762-767页

作者： SHAO Bo LIU Jiansheng ZHAO Ruibin HUANG Zhigang LI Rui School of Electronics and Information Engineering Beihang University Beijing 100191 China

To enhance the integrity, an analytic method （AM） which has less execution time is proposed to calculate the user differential range error （UDRE） used by the user to detect the potential risk. An ephemeris and clock correction calculation method is introduced first. It shows that the most important thing of computing UDRE is to find the worst user location （WUL） in the service volume. Then, a UDRE algorithm using AM is described to solve this problem. By using the covariance matrix of the error vector, the searching of WUL is converted to an analytic geometry problem. The location of WUL can be obtained directly by mathematical derivation. Experiments are conducted to compare the performance between the proposed AM algorithm and the exhaustive grid search （EGS） method used in the master station. The results show that the correctness of the AM algorithm can be proved by the EGS method and the AM algorithm can reduce the calculation time by more than 90%. The computational complexity of this proposed algorithm is better than that of EGS. Thereby this algorithm is more suitable for computing UDRE at the master station.

关键词： satellite navigation user differential range error integrity analytic method worst user location

Research on the Frame Structure and the analytic method of CIA

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科技信息 2009年第35期 1029-1030页

作者：臧艺鹏李悦王亮青岛大学化学化工与环境学院

This paper introduces the concept and the frame structure of CIA,analyzing the most popular methods used in China and comparing the advantages and defects between *** suggestions are also given to the development of CIA.

关键词： CIA Frame structure analytic method

The wave absorption efficiency of multi-layer vertical perforated thin plates

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Journal of Hydrodynamics 2018年第5期30卷 898-907页

作者： Bao-lei Geng Rong-quan Wang De-zhi Ning National Engineering Laboratory for Port Hydraulic Construction Technology Tianjin Research Institute for Water Transportation EngineeringTianjin 300456China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

This paper analyzes the wave absorption efficiency of multi-layer perforated plates in an ideal fluid, based on the linear potential flow theory. The influence of the thickness, the porosity and the layout form of the plates on the wave absorptivity is studied on the assumption that all perforated plates are composed of the same materials and have the same thickness and porosity. The calculation results indicate that the larger the number of layers of the perforated plate set, the better the wave absorption efficiency, however, when the layer number exceeds a certain value, the efficiency of the plates is not significantly increased. For the case of porosity ？= 0.2, thickness b= 0.07 m and 4 layers of perforated plates with a distance l= 1.0 m between the layers, 90% of the energy of the wave within the incident wave period between 1.6 s and 4.4 s can be absorbed.

关键词： Wave absorptivity multi-layer vertical plate porous structure analytic method

On the Character Sum of Polynomials and the Two-term Exponential Sums

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Acta Mathematica Sinica,English Series 2020年第2期36卷 196-206页

作者： Xing Xing LV Wen Peng ZHANG School of Mathematics Northwest University

The main purpose of this paper is using the analytic method and the properties of the character sums to study the computational problem of one kind hybrid power mean involving the character sums of polynomials and the... 详细信息

关键词： Character sums of polynomials two-term exponential sums hybrid power mean analytic method asymptotic formula

analytical solution of crystal diffraction intensity

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Chinese Physics B 2021年第11期30卷 430-433页

作者： Wan-Li Shang Ao Sun Hua-Bin Du Guo-Hong Yang Min-Xi Wei Xu-Fei Xie Xing-Sen Che Li-Fei Hou Wen-Hai Zhang Miao Li Jun Shi Feng Wang Hai-En He Jia-Min Yang Shao-En Jiang Bao-Han Zhang Research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900China College of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Key Laboratory of Optoelectronic Technology and Systems of the Education Ministry of China Chongqing UniversityChongqing 400030China

Plasma density and temperature can be diagnosed by x-ray line emission measurement with crystal,and bent crystals such as von Hamos and Hall structures are proposed to improve the diffraction *** this study,a straightforward solution for the focusing schemes of flat and bent crystals is *** with XOP code are performed to validate the analytical model,and good agreements are *** von Hamos or multi-cone crystal can lead to several hundred times intensity enhancements for a 200μm plasma *** model benefits the applications of the focusing bent crystals.

关键词： crystal diffraction analytic method x-ray diffraction

On the Fourth Power Mean of the Generalized Quadratic Gauss Sums

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Acta Mathematica Sinica,English Series 2018年第6期34卷 1037-1049页

作者： Wen Peng ZHANG Xin LIN School of Mathematics Northwest University

The main purpose of this paper is to use elementary methods and properties of the classical Gauss sums to study the computational problem of one kind of fourth power mean of the generalized quadratic Gauss sums mod q ... 详细信息

关键词： The generalized quadratic Gauss sums the fourth power mean analytic method computational formula

An interesting identity and asymptotic formula related to the Dedekind sums

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Science China Mathematics 2014年第3期57卷 659-663页

作者： XU ZheFeng ZHANG WenPeng Department of Mathematics Northwest University

We use the analytic methods and the properties of Gauss sums to study one kind mean value problems involving the classical Dedekind sums,and give an interesting identity and asymptotic formula for it.

关键词： Dedekind sums mean value analytic method identity asymptotic formula

EXTENSIONS OF SOME INEQUALITIES

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Applied Mathematics(A Journal of Chinese Universities) 2001年第3期16卷 241-243页

作者： Chen Daoqiof Math., Zhejiang Univ., Hangzhou, 310027. Dept. of Math. Zhejiang Univ. Hangzhou

By using a simple analytic method the following inequalities are proved:(b x+y -a x+y )/(b x-a x)≥[(x+y)/x][(a+b)/2] y, for 00,x+y≥2; (b x+y -a x+y )/(b x-a x)0,x+y≤2. These inequalities are the extensions of inequalities of Qi Feng, Xu Senlin and Zheng Lin. And a conjection of Qi Feng is proved not true.

关键词： analytic method inequality extension conjection.

Application of the four models of directional spectra in the Bohai Sea

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Acta Oceanologica Sinica 1995年第1期14卷 15-22页

作者： Wu Xiujie and Teng Xuechun(First Institute of Oceanography, State Oceanic Administration, Qinghao 266003, China)

According to the wind-wave individual case directional spectra obtained from the instrument array and'956' wave buoy measures, the wind-wave directional spectra presented by Mitsuyasu, Donelan and Hasselmann onthe basis of the observations as well as theoretical wind-wave directional spectra by Wen Shengchang on the basis ofanalytic method are compared and checked from the pointview of total energy. Results show that Mitsuyasu's directional spectra are well identical with the measured wind-wave directional spectra developing fully in the Bohai ***'s and theoretical wind-wave directional spectra are also quite consistent with the measured results in the development of the wind waves, especially best with the measured results in the initial stage of the development of thewind waves.

关键词： Wind-wave directional spectrum wave energy ratio analytic method developing state instrument array.