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Monte Carlo simulation of the electromagnetic wave propagation in the duststorm

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Science China(Physics,Mechanics & Astronomy) 2008年第8期51卷 1001-1009页

作者： GAO ZhiWen ZHOU YouHe ZHENG XiaoJing Key Laboratory of Mechanics on Western Disaster and Environment Ministry of EducationDepartment of MechanicsLanzhou UniversityLanzhou 730000China

Monte Carlo simulations of the extinction rate of electromagnetic wave propagation in the duststorm were presented. The numerical procedure was based on the multiple scattering and independent scattering. The calculated multiple scattering attenuation rate is in good agreement with the measured one,but differs significantly from those obtained under the independent scattering assumption. At the same time,the factors of size parameter,frequency of incident wave,the angle of incident,and sands permittivity and water content have been considered in the attenuation of electromagnetic wave propagation in the duststorm. Numerical results obtained showed that the attenuation rate increases as the fractional volume,frequency of incident wave and sands permittivity increase,and as the angle of incident increases,the attenuation rate decreases.

关键词： Monte Carlo simulation electromagnetic wave duststorm multiple-scattering independent scattering attenuation rate

Relationship Between Language and Thought:Linguistic Determinism,Independence,or Interaction?

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Journal of Contemporary Educational Research 2022年第5期6卷 32-37页

作者： Jing Li Anhui Vocational and Technical College Hefei 230000Anhui ProvinceChina

The relationship between language and thought has long been a topic of great interest in the field of linguistics,especially in psycholinguistics.Herder,Humboldt,Trendelenburg Sapir,Whorf,Gui Shichun,Lian Shuneng,and Bao Human are some of the well-known scholars who have conducted research on the relationship between language and thought.With regard to the relationship between language and thought,there are three main viewpoints.The first group of scholars,represented by Sapir and Whorf,supports linguistic determinism.Some scholars believe that language and thought are mutually independent.However,others believe that language and thought are inseparable.Beginning from Sapir-Whorf hypothesis and their theory of linguistic determinism and linguistic relativity,this article agrees with the influence of language over thought but refutes the extreme viewpoint of linguistic determinism from several points,proving the independence and mutual influence of language and thought.This article finally concludes that the preferred relationship between language and thought should be that they are independent but interactive.

关键词： Language Thought Linguistic determinism Interactive independent

TOPOLOGICAL CONDITIONS FOR FAULT DIAGNOSABILITY AT SUBNETWORK-LEVEL

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Science China Mathematics 1992年第9期35卷 1117-1125页

作者：黄东泉叶风杨祖樱 Department of Electrical Engineering Fuzhou University Fuzhou 350002 PRC

The fault analysis of analog circuits at subnetwork-level is confronted with two essentialcore problems: (ⅰ) Is it necessary that all the torn nodes are accessible? (ⅱ) Are there any topological conditions of subnetwork which guarantee the fault at subnetwork-level to bediagnosed correctly? This paper answers the two problems in two theorems. The conditions are necessary and almost sufficient, and if all the torn nodes are accessible, the required topological conditions can be almost satisfied automatically. This is a special situation of our research on the distribution of the accessible nodes.

关键词： fault at subnetwork-level diagnosability independent path.

Opportunities of New Uzbekistan Attract Investors

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Beijing Review 2023年第20期66卷 22-25页

作者： Obid Khakimov Center for Economic Research and Reforms under the Administration of the President of the Republic of Uzbekistan (CERR)

The results of the Second Tashkent International Investment Forum(TIIF-2023),on April 27-28,are in.It was attended by about 2.500 represen-tatives of business,banking and financial sectors from 70 counties,including the U.S.,European Union countries,Great Britain,Turkiye,China,India,Egypt,Commonwealth of independent States countries,and coun-tries in Southeast Asia and the Middle East.

关键词： Britain Middle independent

On Enomoto's problems in a bipartite graph

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Science China Mathematics 2009年第9期52卷 1947-1954页

作者： YAN Jin GAO YunShu School of Mathematics Shandong UniversityJinan 250100China

In this paper, we obtain the following result: Let k, n1 and n2 be three positive integers, and let G=(V1, V2; E) be a bipartite graph with |V1|=n1 and |V2|=n2 such that n1 2k + 1, n2 2k + 1 and |n1-n2| 1. If d(x) + d(y) 2k + 2 for every x∈V1 and y∈V2 with xy( ∈/)E(G), then G contains k independent cycles. This result is a response to Enomoto's problems on independent cycles in a bipartite graph.

关键词： bipartite graph balanced bipartite graph independent cycle

The First Discovery of a Tin Deposit Related to Hercynian A-Type Granites in China

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Science China Chemistry 1993年第4期36卷 490-498页

作者：毕承思沈湘元徐庆生 Institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing 100037 PRC

This paper introduces the petrological, mineralogical and geochemical fea. tures of the rocks hosting the Sareshik tin deposit—an independent tin deposit related to Hercynian A-type granites discovered in China in 1987. A comparison with the features of A-type granites at home and abroad indicates that some of their petrological features are more typical than those of famous A-type granites of Nigeria. The geological features of the tin deposit are salient and notably different from those of some famous tin deposits in China, so the deposit may represent China’s deposits associated with anorogenic granites. This tin deposit was formed in the Hercynian Stage. This type of tin deposit was for the first time discovered in China and is also rare in the world. It is a new type of tin deposit in China.

关键词： Hercynian anorogenie or post-orogenic granites A-type(alkali)granires independent tin deposit.

Structures,Aromaticity and Raman Spectroscopy of Double Hanging Ring Molecules[(GnHn-1^m)(GnHn-1^m)](G=C,Si,Ge;n=3,5,6,7,8;m=+1,-1,0,+1,+2)

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Chinese Journal of Structural Chemistry 2020年第2期39卷 214-228,184页

作者：沈臣飞刘子忠刘红霞韩立楠 Chemistry and Environment Science College Inner Mongolia Normal UniversityInner Mongolia Key Laboratory of Green CatalysisHohhotInner Mongolia 010022China School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200062China

Theoretical calculations of Double Hanging Ring Molecule(DHRM) [(GnHn-1^m)(GnHn-1^m)](G=C,Si,Ge;n=3,5,6,7,8;m=+1,-1,0,+1,+2) were performed via Gaussian 09 with the method of Density Functional Theory(DFT). Geometrical optimization, Potential Energy surface Scan(PES), Degree of Aromaticity(DOA) and Nucleus independent Chemical Shift(NICS) were computed to study the optimal structures and aromaticity of DHRMs. Ring Stretching Vibration Raman Spectroscopy(RSVRSF) was predicted to seek the relation between RSVRSF and aromaticity of DHRMs. The results show optimal structures of DHRMs[(GnH(n-1)~m)(GnH(n–1)~m)](n = 3, 5~8);DA = 90° is the stable structure when n = 3, 7, 8;while n = 5 corresponds to DA = 30°, n = 6 corresponds to DA = 50°;the correlation between DOA and NICS of DHRMs is quadratic;the value of RSVRSF of DHRM approximates to its corresponding single ring molecule, which could act as characteristic frequency of ring molecule to identify its aromaticity;the correlation between RSVRSF and DOA is quadratic, and that between RSVRSF and NICS is linear.

关键词： double hanging ring molecule(DHRM) degree of aromaticity(DOA) nucleus independent chemical Shift(NICS) ring stretching vibration Raman spectroscopy(RSVRSF)

Inversion Study on Pollutant Discharges in the Bohai Sea with the Adjoint Method

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Journal of Ocean University of China 2015年第6期14卷 941-950页

作者： SHEN Youli WANG Chunhui WANG Yonggang LV Xianqing Physical Oceanography Laboratory Ocean University of China Beihai Marine Environmental Monitoring Center Station of SOA Key Laboratory of Marine Spill Oil Identification and Damage Assessment Technology North China Sea Branch of State Oceanic Administration The First Institute of Oceanography SOA

The adjoint method is presented which could be used to estimate the time-varying contamination concentration(CC) from pollution source(PS). Then the pollutant flux is calculated. In order to guarantee the continuity of pollutant distribution and make the calculated results more accurate, the independent point(IP) scheme is proposed. The contamination concentrations(CCs) at some time steps are selected as the independent points(IPs), and only CCs at these IPs are optimized while CCs at other points are calculated through linear interpolation of the independent CCs. In twin numerical experiments, all the given distributions are successfully inverted with the adjoint method. The cost functions and the mean absolute errors(MAEs) in concentrations and pollutant fluxes decrease greatly after assimilation, and the cost functions are reduced by about 5 orders of magnitude compared with their initial values. The results indicate that the adjoint method is computationally efficient to recover CCs from PS. It is easier to invert the given distribution which is less complex. The inversion efficiency with IP scheme is raised compared to that without this scheme. The IP scheme is significant for the inversion result, in which appropriate IP number could yield better inversion results. More work will be done to apply this method to real experiment.

关键词： adjoint method time-varying variable contamination concentration pollutant flux independent point scheme

C^0 and C^1 theories and test functions for FEM patch test in microstructures

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Science China(Physics,Mechanics & Astronomy) 2010年第6期53卷 1086-1093页

作者： CHEN WanJi Institute for Structural Analysis of Aerocraft,Shenyang Aerospace University,Shenyang 110136,China Institute for Structural Analysis of Aerocraft Shenyang Aerospace University Shenyang China

Among many theories and categories in microstructures,rotation-displacement used as "independent" or "dependent" variables,is a noticeable topic. In FEM,it is called C0 and C1 theory. The convergence criteria of finite elements for microstructures are less mature than those for the conventional thin plate bending problem. In this paper,the patch test functions for assessing convergence of the C0 and C1 finite elements in microstructures is established based on the enhanced patch test theory. The author has further explored the C0 and C1 finite element theories and investigated the difference and correlation between their finite element formulations. Newly proposed finite element theories for microstructures are as follows:(1) the displacement-rotation dependent C1 element that requires the element function satisfying both C0 and C1 continuity;(2) the displacement-rotation independent C0 element which requires new convergence criteria,such as non-zero constant shear stress patch test and zero constant shear stress patch test for approximating C1 element.

关键词： couple stress theory displacement-rotation dependent theory displacement-rotation independent theory finite element method for microstructures test function for patch test