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泸溪(浦市)方言的指示词略论
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作者 秦朗 周敏莉 《牡丹江师范学院学报(社会科学版)》 2017年第3期131-135,共5页
泸溪(浦市)方言的指示词是远近二分体系。其特点如下:基本指示词"这/那"可以单独作"是"字句的主语,但不能单独作宾语。主要的名物指示词为"这条/那条";处所指示和时间指示都受到普通话的影响;数量指示词&... 泸溪(浦市)方言的指示词是远近二分体系。其特点如下:基本指示词"这/那"可以单独作"是"字句的主语,但不能单独作宾语。主要的名物指示词为"这条/那条";处所指示和时间指示都受到普通话的影响;数量指示词"这蒲/那蒲"是中性词,而"这何/那何"主观性较强。方式程度指示词主要有"这么/那么""这么条/那么条"两组,但二者的句法功能有较大区别。 展开更多
关键词 浦市方言 指示词 数量 方式/程度
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A-high-order Accuraqcy Implicit Difference Scheme for Solving the Equation of Parabolic Type 被引量:7
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作者 马明书 王肖凤 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期94-97,共4页
In this paper,a implicit difference scheme is proposed for solving the equation of one_dimension parabolic type by undetermined paameters.The stability condition is r=αΔt/Δx 2 1/2 and the truncation error is o(... In this paper,a implicit difference scheme is proposed for solving the equation of one_dimension parabolic type by undetermined paameters.The stability condition is r=αΔt/Δx 2 1/2 and the truncation error is o(Δt 4+Δx 4) It can be easily solved by double sweeping method. 展开更多
关键词 equation of one_dimension parabolic type high_order accuracy implicit difference scheme
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A Family of High_order Accuracy Explicit Difference Schemes for Solving 2-D Parabolic Partial Differential Equation 被引量:4
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作者 任宗修 陈贞忠 王肖凤 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期57-61,共5页
A family of high_order accuracy explicit difference schemes for solving 2_dimension parabolic P.D.E. are constructed. Th e stability condition is r=Δt/Δx 2=Δt/Δy 2【1/2 and the truncation err or is O(Δt 3+Δx... A family of high_order accuracy explicit difference schemes for solving 2_dimension parabolic P.D.E. are constructed. Th e stability condition is r=Δt/Δx 2=Δt/Δy 2【1/2 and the truncation err or is O(Δt 3+Δx 4). 展开更多
关键词 D parabolic P.D.E high_order accuracy explic it difference scheme
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UPWIND SCHEME FOR IDEAL 2-D MHD FLOWS BASED ON UNSTRUCTURED MESH 被引量:1
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作者 潘勇 王江峰 伍贻兆 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第1期1-7,共7页
An upwind scheme based on the unstructured mesh is developed to solve ideal 2-D magnetohydrodynamics (MHD) equations. The inviscid fluxes are approximated by using the modified advection upstream splitting method (... An upwind scheme based on the unstructured mesh is developed to solve ideal 2-D magnetohydrodynamics (MHD) equations. The inviscid fluxes are approximated by using the modified advection upstream splitting method (AUSM) scheme, and a 5-stage explicit Runge-Kutta scheme is adopted in the time integration. To avoid the influence of the magnetic field divergence created during the simulation, the hyperbolic divergence cleaning method is introduced. The shock-capturing properties of the method are verified by solving the MHD shock-tube problem. Then the 2-D nozzle flow with the magnetic field is numerically simulated on the unstructured mesh. Computational results demonstrate the effects of the magnetic field and agree well with those from references. 展开更多
关键词 ideal magnetohydrodynamics equation unstructured mesh advection upstream splitting method(AUSM) scheme divergence cleaning
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EFFECTIVE DETECTION DEPTH OF NEEDLE-LIKE OPTICAL PROBE
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作者 李韪韬 钱志余 +1 位作者 陈春晓 肖笛 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第1期76-80,共5页
The effective detection depth of the needle-like optical probe is studied. The light transport model in highly scattering tissue is the diffusion equation and the boundary is Neuman. The sensitivity matrix is related ... The effective detection depth of the needle-like optical probe is studied. The light transport model in highly scattering tissue is the diffusion equation and the boundary is Neuman. The sensitivity matrix is related to the position of the light source and the detector. It can be used to evaluate the effective detection depth. The sensitivity matrix is defined as the multiplication of the source and detector hght distribution. Six different groups about ix parameters including the source diameter and detector fibers, the core-to-core distance between the source and detector fibers, the opotode depth, the absorption, and reduced scattering coefficient, are used as experimental models. The relationship between the six parameters and the effective detection depth is analyzed. Resuits can be used to study the spatial resolution and the depth of multi-fibers. 展开更多
关键词 probes optical fibers effective detection depth diffusion equation needle-like optical probe
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Solving single-frequency phase ambiguity using parameter weights fitting and constrained equation ambiguity resolution methods 被引量:5
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作者 阳仁贵 欧吉坤 +3 位作者 袁运斌 张克非 闻德保 Ron Grenfell 《Journal of Central South University of Technology》 EI 2006年第1期93-98,共6页
Based on the structural characteristics of the double-differenced normal equation, a new method was proposed to resolve the ambiguity float solution through a selection of parameter weights to construct an appropriate... Based on the structural characteristics of the double-differenced normal equation, a new method was proposed to resolve the ambiguity float solution through a selection of parameter weights to construct an appropriate regularized matrix, and a singular decomposition method was used to generate regularization parameters. Numerical test results suggest that the regularized ambiguity float solution is more stable and reliable than the least-squares float solution. The mean square error matrix of the new method possesses a lower correlation than the variancecovariance matrix of the least-squares estimation. The size of the ambiguity search space is reduced and the search efficiency is improved. The success rate of the integer ambiguity searching process is improved significantly when the ambiguity resolution by using constraint equation method is used to determine the correct ambiguity integervector. The ambiguity resolution by using constraint equation method requires an initial input of the ambiguity float solution candidates which are obtained from the LAMBDA method in the new method. In addition, the observation time required to fix reliable integer ambiguities can he significantly reduced. 展开更多
关键词 global position system ill-conditioned state parameter weight fitting method constraint equation integer ambiguity
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Lie Symmetry Groups of(2+1)-Dimensional BKP Equation and Its New Solutions 被引量:1
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作者 MA Hong-Cai LOU Sen-Yue DENG Ai-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期685-688,共4页
A modified direct method is developed to find finite symmetry groups of nonlinear mathematical physicssystems.Applying the modified direct method to the well-known (2+1)-dimensional BKP equation we get its symmetry.Fu... A modified direct method is developed to find finite symmetry groups of nonlinear mathematical physicssystems.Applying the modified direct method to the well-known (2+1)-dimensional BKP equation we get its symmetry.Furthermore,the exact solutions of (2+1)-dimensional BKP equation are obtained through symmetry analysis. 展开更多
关键词 (2+1)-dimensional BKP equation Lie symmetry group CK's direct method exact solution
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Nonliner Analysis of a Synthesized Optimal Velocity Model for Traffic Flow 被引量:3
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作者 ZHU Wen-Xing JIA Lei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期505-510,共6页
We analyze a new car-following model described by a differential-difference equation with a synthesized optimal velocity function (SOVF),which depends on the front interactions between every two adjacent vehicles inst... We analyze a new car-following model described by a differential-difference equation with a synthesized optimal velocity function (SOVF),which depends on the front interactions between every two adjacent vehicles instead of the weighted average headway.The model is analyzed with the use of the linear stability theory and nonlinear analysis method.The stability and neutral stability condition are obtained.We also derive the modified KdV (Korteweg-de Vries) equation and the kink-antikink soliton solution near the critical point.A simulation is conducted with integrating the differential-difference equation by the Euler scheme.The results of the numerical simulation verify the validity of the new model. 展开更多
关键词 multi-interaction nonlinear analysis modified KdV equation SOVF
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A High-order Accuracy Explicit Difference Scheme with Branching Stability for Solving Higher-dimensional Heat-conduction Equation 被引量:3
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作者 MA Ming-shu MA Ju-yi +1 位作者 GU Shu-min ZHU Lin-lin 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期446-452,共7页
A high-order accuracy explicit difference scheme for solving 4-dimensional heatconduction equation is constructed. The stability condition is r = △t/△x^2 = △t/△y^2 = △t/△z^2 = △t/△w^2 〈 3/8, and the truncatio... A high-order accuracy explicit difference scheme for solving 4-dimensional heatconduction equation is constructed. The stability condition is r = △t/△x^2 = △t/△y^2 = △t/△z^2 = △t/△w^2 〈 3/8, and the truncation error is O(△t^2 + △x^4). 展开更多
关键词 heat-conduction equation explicit difference scheme high-order accuracy branching stability
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The Two Patterns of High Exact Difference in Convection Equation 被引量:2
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作者 YANGHui PENGXing 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第3期328-330,共3页
This paper gives two patterns of high exact d ifference in solving convection equation. The error of cut section is to O(Δ t 2+Δx 4).
关键词 convection equation the pattern of difference the e rror of cut section
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Rainfall and Tillage Impacts on Soil Erosion of Sloping Cropland with Subtropical Monsoon Climate- A Case Study in Hilly Purple Soil area, China 被引量:9
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作者 TANG Jia-liang CHENG Xun-qiang +5 位作者 ZHU Bo GAO Mei-rong WANG Tao ZHANG Xi-feng ZHAO Pei YOU Xiang 《Journal of Mountain Science》 SCIE CSCD 2015年第1期134-144,共11页
Under global warming, storm events tend to intensify, particularly in monsoon-affected regions. As an important agricultural area in China, the purple soil region in the Sichuan Basin, where it has a prevailing monsoo... Under global warming, storm events tend to intensify, particularly in monsoon-affected regions. As an important agricultural area in China, the purple soil region in the Sichuan Basin, where it has a prevailing monsoon climate, is threatened by serious soil erosion. Tillage operations alter runoff and soil erosion processes on croplands by changing the physical properties of the soil surface. To clarify the relationship between tillage and soil erosion in the purple soil region, three different tillage practices in this region were investigated at the plot scale over 4 years: bare land with minimum tillage (BL), conventional tillage (CT) and seasonal no-tillage ridges (SNTR) which was initially designed to prevent soil erosion by contoured ridges and no-tillage techniques. The results showed that although there were no significant differences in the surface runoff and soil erosion among the three oractices, BL caused relatively high surface runoff and soil erosion, followed by CT and SNTR. Classification and comparison of the rainfall events based on cluster analysis (CA) verified that the surface runoff was not significantly different between most intensive event and long intensive events but was significantly different between most intensive and short and medium-duration events. Only the rainfall events with the highest rainfall intensity could trigger serious soil erosion, up to 1000 kg ha^-1 in the region. Further detailed investigations on the effects of tillage operations on the soil erosion in a subtropical region with a monsoon climate are needed to provide a basis for modeling catchments and designing better management practices. 展开更多
关键词 Soil erosion Purple soil Tillage types Rainfall intensity Cluster analysis.
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Modeling and monitoring of nonlinear multi-mode processes based on similarity measure-KPCA 被引量:10
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作者 WANG Xiao-gang HUANG Li-wei ZHANG Ying-wei 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第3期665-674,共10页
A new modeling and monitoring approach for multi-mode processes is proposed.The method of similarity measure(SM) and kernel principal component analysis(KPCA) are integrated to construct SM-KPCA monitoring scheme,wher... A new modeling and monitoring approach for multi-mode processes is proposed.The method of similarity measure(SM) and kernel principal component analysis(KPCA) are integrated to construct SM-KPCA monitoring scheme,where SM method serves as the separation of common subspace and specific subspace.Compared with the traditional methods,the main contributions of this work are:1) SM consisted of two measures of distance and angle to accommodate process characters.The different monitoring effect involves putting on the different weight,which would simplify the monitoring model structure and enhance its reliability and robustness.2) The proposed method can be used to find faults by the common space and judge which mode the fault belongs to by the specific subspace.Results of algorithm analysis and fault detection experiments indicate the validity and practicability of the presented method. 展开更多
关键词 process monitoring kernel principal component analysis (KPCA) similarity measure subspace separation
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Kinetic Behaviors of a Competitive Population and Fitness System in Exchange-Driven Growth
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作者 LU Ke LIN Zhen-Quan SUN Yun-Fei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期105-110,共6页
We proposed an aggregation model of two species aggregates of fitness and population to study the interaction between the two species in their exchange-driven processes of the same species by introducing the monomer b... We proposed an aggregation model of two species aggregates of fitness and population to study the interaction between the two species in their exchange-driven processes of the same species by introducing the monomer birth of fitness catalyzed by the population, where the fitness aggregates perform self-death process and the population aggregates perform self-birth process. The kinetic behaviors of the aggregate size distributions of the fitness and population were analyzed by the rate equation approach with their exchange rate kernel K1(k,j) = K1kj and K2(k,j) = K2kj, the fitness aggregate's self-death rate kernel J1 ( k ) = J1 k, population aggregate's self-birth rate kernel J2( k ) = J2k and population-catalyzed fitness birth rate kernel I(k,j) = Ikj'. The kinetic behavior of the fitness was found depending crucially on the parameter v, which reflects the dependence of the population-catalyzed fitness birth rate on the size of the catalyst (population) aggregate. (i) In the v ≤ 0 case, the effect of catalyzed-birth of fitness is rather weak and the exchange-driven aggregation and self-death of the fitness dominate the process, and the fitness aggregate size distribution αk(t) does not have scale form. (ii) When v ≥0, the effect of the population-catalyzed birth of fitness gets strong enough, and the catalyzed-birth and self-death of the fitness aggregates, together with the self-birth of the population aggregates dominate the evolution process of the fitness aggregates. The aggregate size distribution αk (t) approaches a generalized scaling form. 展开更多
关键词 kinetic behavior aggregate growths catalyzed-birth rate equations
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Analysis of the blunting line in ductile fracture toughness J_(IC) test method
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作者 尹建成 刘瑞堂 杨卓青 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第4期524-527,共4页
The blunting line equation is very important in J-integral testing because of its indispensability in the determination of valid data and JIC value. The blunting line equation in current standard has had a larger rela... The blunting line equation is very important in J-integral testing because of its indispensability in the determination of valid data and JIC value. The blunting line equation in current standard has had a larger relative error in depiction of the crack blunting compared to the experimentally measured results. By analyzing the blunting process of the crack tip according to the D-B model, a new form of blunting line was obtained on the base of the path independence of J-integral, i.e., J=1.25(σs+Sf)/(1+n)·WSZ. Experimental results show that this equation is more precise to describe the crack blunting than those in current standards. 展开更多
关键词 J-INTEGRAL path independence blunting line
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Intelligent Machine Theory--A Key Approach to Initiate the Age of Designing Thinking Computers
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作者 Mustafa Pehlivan 《Journal of Mathematics and System Science》 2013年第8期417-418,共2页
The purpose of this paper is to introduce an unknown method for finding a real possible x value of any degree polynomial equation and to show how this can be applied to make computers which are at least x1000 (one th... The purpose of this paper is to introduce an unknown method for finding a real possible x value of any degree polynomial equation and to show how this can be applied to make computers which are at least x1000 (one thousand times) faster than today's existing highest speed computers. Since one of the Milennium Prize Problems offered by Claymath asks about whether P (Deterministic Polynomial) is equal to NP (Non-Deterministic Polynomial) (what that means informally is that whether we can design a computer which can quickly solve a certain complicated problem can also verify the solution quickly (and vice versa). Fortunately, the answer to P vs. NP problem based on my findings in certain algebraic algorythms is yes although there have been many people who claimed the answer is no. What that means is that humans can make machines that work very fast and close to human intelligence in the identification of, say, certain proteins and amino acids, in case my theory is proven to be a fact. This paper is therefore an initial stage of planting the first seeds of the process, in terms of describing how exactly this can happen, theoretically of course, since everything in Science begins with a theory based on the outcome of a hypothesis. 展开更多
关键词 FORMULA POLYNOMIAL equation x DEGREE function power solution milennium PRIZE problem
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Gas-Fluid and Fluid-Solid Phase Instability for Restricted Primitive Model
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作者 GUO Yuan-Yuan CHEN Xiao-Song 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第8期356-360,共5页
By considering the fluctuation of grand potential f~ around equilibrium with respect to small one-particle density fluctuations δpα(r→), the phase instability of restricted primitive model (RPM) of ionic system... By considering the fluctuation of grand potential f~ around equilibrium with respect to small one-particle density fluctuations δpα(r→), the phase instability of restricted primitive model (RPM) of ionic systems is investigated. We use the integral equation theory to calculate the direct correlation functions in the reference hypernetted chain approximation and obtain the spinodai line of RPM. Our anaiysis explicitly indicates that the gas-fluid phase instability is induced by k = 0 fluctuation mode, while the fluid-solid phase instability is related to k ≠ 0 fluctuation modes. The spinodai line is qualitatively consistent with the result of computer simulations by others. 展开更多
关键词 phase instability restricted primitive model the reference hypernetted chain approximation
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Ultrasonic study on molecular interactions in binary mixtures of formamide with 1-propanol or 2-propanol
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作者 Manju Rani Suman Gahlyan +1 位作者 Ankur Gaur Sanjeev Maken 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第4期689-698,共10页
Ultrasonic speeds have been measured at 298.15 K and 308.15 K for mixtures of formamide + 1 -propanol or 2-propanol. For an equimolar mixture, excess molar compressibility follows the sequence of l-propanol 〉 2-prop... Ultrasonic speeds have been measured at 298.15 K and 308.15 K for mixtures of formamide + 1 -propanol or 2-propanol. For an equimolar mixture, excess molar compressibility follows the sequence of l-propanol 〉 2-propanol. The ultrasonic speed data are correlated by various correlations such as Nomoto's relation, van Dael's mixing relation and impedance dependence relation, and analyzed in terms of Jacobson's free length theory and Schaaffs collision factor theory. Excess isentropic compressibility is calculated from ex- perimental ultrasonic speed data and previously reported excess volume data. The excess molar ultrasonic speed and isentropic compressibility values are fitted to Redlich-Kister polynomial equation. Other proper- ties such as molecular association, available volume, free volume, and intermolecular free length are also calculated. The excess isentropic compressibility data are also interpreted in terms of graph theoretical ap- proach. The calculated isentropic compressibility values are well consistent with the experimental data. It is found that the interaction between formamide and propanol increases when hydroxyl group attached to a carbon atom has more -CH3 groups. 展开更多
关键词 Ultrasonic speedGraph theoretical approachFormamidePropanollntermolecular interaction
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Effect of Spatial Dimension and External Potential on Joule-Thomson Coefficients of Ideal Bose Gases
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作者 袁都奇 王参军 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第4期669-672,共4页
Based on the form of the n-dimensional generic power-law potential, the state equation and the heat capacity, the analytical expressions of the Joule-Thomson coefficient (3TC) for an ideal Bose gas are derived in n-... Based on the form of the n-dimensional generic power-law potential, the state equation and the heat capacity, the analytical expressions of the Joule-Thomson coefficient (3TC) for an ideal Bose gas are derived in n-dimensional potential. The effect of the spatial dimension and the external potential on the JTC are discussed, respectively. These results show that: (i) For the free ideal Bose gas, when n/s ≤ 2 (n is the spatial dimension, s is the momentum index in the relation between the energy and the momentum), and T → Tc (Tc is the critical temperature), the JTC can obviously improve by means of changing the throttle valve's shape and decreasing the spatial dimension of gases. (ii) For the inhomogeneous external potential, the discriminant △= [1 - y∏^ni=1(kT/εi)^1/tiГ(1/ti+1)] (k is the Boltzmann Constant, T is the thermodynamic temperature, ε is the external field's energy), is obtained. The potential makes the JTC increase when △ 〉 0, on the contrary, it makes the JTC decrease when A 〈△. (iii) In the homogenous strong external potential, the JTC gets the maximum on the condition of kTεi〈〈1. 展开更多
关键词 ideal Bose gases Joule-Thomson coefficient spatial dimension external potential field
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On the Kinetic Formulation of a Nonlinear Hyperbolic Variational Wave Equation
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作者 姜玲玉 程素萍 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2005年第1期72-75,共4页
Motivated by [3], [4] and [5], we present the kinetic formulation of a nonlinear variational wave equation corresponding to some specific weak solutions . This equation arises from studies in nematic liquid crystals, ... Motivated by [3], [4] and [5], we present the kinetic formulation of a nonlinear variational wave equation corresponding to some specific weak solutions . This equation arises from studies in nematic liquid crystals, long wave on a dipole chain and a few other fields. 展开更多
关键词 kinetic formulation variational wave equation Radon measure
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A divergence-free weak Galerkin method for quasi-Newtonian Stokes flows 被引量:4
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作者 ZHENG XiaoBo CHEN Gang XIE XiaoPing 《Science China Mathematics》 SCIE CSCD 2017年第8期1515-1528,共14页
This paper proposes a weak Galerkin finite element method to solve incompressible quasi-Newtonian Stokes equations. We use piecewise polynomials of degrees k + 1(k 0) and k for the velocity and pressure in the interio... This paper proposes a weak Galerkin finite element method to solve incompressible quasi-Newtonian Stokes equations. We use piecewise polynomials of degrees k + 1(k 0) and k for the velocity and pressure in the interior of elements, respectively, and piecewise polynomials of degrees k and k + 1 for the boundary parts of the velocity and pressure, respectively. Wellposedness of the discrete scheme is established. The method yields a globally divergence-free velocity approximation. Optimal priori error estimates are derived for the velocity gradient and pressure approximations. Numerical results are provided to confirm the theoretical results. 展开更多
关键词 quasi-Newtonian Stokes equation weak Galerkin method DIVERGENCE-FREE optimal error estimate
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