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A Content-Based Medical Image Retrieval Method Using Relative Difference-Based Similarity Measure
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作者 Ali Ahmed Alaa Omran Almagrabi Omar MBarukab 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期2355-2370,共16页
Content-based medical image retrieval(CBMIR)is a technique for retrieving medical images based on automatically derived image features.There are many applications of CBMIR,such as teaching,research,diagnosis and elect... Content-based medical image retrieval(CBMIR)is a technique for retrieving medical images based on automatically derived image features.There are many applications of CBMIR,such as teaching,research,diagnosis and electronic patient records.Several methods are applied to enhance the retrieval performance of CBMIR systems.Developing new and effective similarity measure and features fusion methods are two of the most powerful and effective strategies for improving these systems.This study proposes the relative difference-based similarity measure(RDBSM)for CBMIR.The new measure was first used in the similarity calculation stage for the CBMIR using an unweighted fusion method of traditional color and texture features.Furthermore,the study also proposes a weighted fusion method for medical image features extracted using pre-trained convolutional neural networks(CNNs)models.Our proposed RDBSM has outperformed the standard well-known similarity and distance measures using two popular medical image datasets,Kvasir and PH2,in terms of recall and precision retrieval measures.The effectiveness and quality of our proposed similarity measure are also proved using a significant test and statistical confidence bound. 展开更多
关键词 Medical image retrieval feature extraction similarity measure fusion method
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Load Reduction Test Method of Similarity Theory and BP Neural Networks of Large Cranes 被引量:4
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作者 YANG Ruigang DUAN Zhibin +2 位作者 LU Yi WANG Lei XU Gening 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第1期145-151,共7页
Static load tests are an important means of supervising and detecting a crane's lift capacity. Due to space restrictions, however, there are difficulties and potential danger when testing large bridge cranes. To solv... Static load tests are an important means of supervising and detecting a crane's lift capacity. Due to space restrictions, however, there are difficulties and potential danger when testing large bridge cranes. To solve the loading problems of large-tonnage cranes during testing, an equivalency test is proposed based on the similarity theory and BP neural networks. The maximum stress and displacement of a large bridge crane is tested in small loads, combined with the training neural network of a similar structure crane through stress and displacement data which is collected by a physics simulation progressively loaded to a static load test load within the material scope of work. The maximum stress and displacement of a crane under a static load test load can be predicted through the relationship of stress, displacement, and load. By measuring the stress and displacement of small tonnage weights, the stress and displacement of large loads can be predicted, such as the maximum load capacity, which is 1.25 times the rated capacity. Experimental study shows that the load reduction test method can reflect the lift capacity of large bridge cranes. The load shedding predictive analysis for Sanxia 1200 t bridge crane test data indicates that when the load is 1.25 times the rated lifting capacity, the predicted displacement and actual displacement error is zero. The method solves the problem that lifting capacities are difficult to obtain and testing accidents are easily possible when 1.25 times related weight loads are tested for large tonnage cranes. 展开更多
关键词 similarity theory BP neural network large bridge crane load reduction equivalent test method
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A simple method for solving unidirectional methane gas flow in coal seam based on similarity solution 被引量:2
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作者 Zhou Yan Meng Qian +2 位作者 Lin Baiquan Qin Jilong Zhou Guiping 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第2期331-334,共4页
The equation used to model the unidirectional flow of methane gas in coal seams is usually formulated as a nonlinear partial differential equation, which needs to be solved numerically with a computer program.Neverthe... The equation used to model the unidirectional flow of methane gas in coal seams is usually formulated as a nonlinear partial differential equation, which needs to be solved numerically with a computer program.Nevertheless, for people without access to the computer program, the conventional numerical method may be inconvenient. Thus, the objective here is to seek some method simpler than the conventional one for solving the flow problem. A commonly used model of the unidirectional methane gas flow is considered, where the methane adsorption is described by the Langmuir isotherm and the free gas is treated as real gas. By introducing the similarity solution, a simple method for solving the flow model is proposed, which can be done on a hand calculator. It is shown by two examples that the gas pressure profile obtained by the proposed method agrees well with the direct numerical solution of the flow model. 展开更多
关键词 Coalbed METHANE Migration UNIDIRECTIONAL flow similarity solution Simplified SOLVING Numerical method
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Scale Effects and a Method for Similarity Evaluation in Micro Electrical Discharge Machining 被引量:1
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作者 LIU Qingyu ZHANG Qinhe +3 位作者 WANG Kan ZHU Guang FU Xiuzhuo ZHANG Jianhua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第6期1193-1199,共7页
Electrical discharge machining(EDM) is a promising non-traditional micro machining technology that offers a vast array of applications in the manufacturing industry. However, scale effects occur when machining at th... Electrical discharge machining(EDM) is a promising non-traditional micro machining technology that offers a vast array of applications in the manufacturing industry. However, scale effects occur when machining at the micro-scale, which can make it difficult to predict and optimize the machining performances of micro EDM. A new concept of "scale effects" in micro EDM is proposed, the scale effects can reveal the difference in machining performances between micro EDM and conventional macro EDM. Similarity theory is presented to evaluate the scale effects in micro EDM. Single factor experiments are conducted and the experimental results are analyzed by discussing the similarity difference and similarity precision. The results show that the output results of scale effects in micro EDM do not change linearly with discharge parameters. The values of similarity precision of machining time significantly increase when scaling-down the capacitance or open-circuit voltage. It is indicated that the lower the scale of the discharge parameter, the greater the deviation of non-geometrical similarity degree over geometrical similarity degree, which means that the micro EDM system with lower discharge energy experiences more scale effects. The largest similarity difference is 5.34 while the largest similarity precision can be as high as 114.03. It is suggested that the similarity precision is more effective in reflecting the scale effects and their fluctuation than similarity difference. Consequently, similarity theory is suitable for evaluating the scale effects in micro EDM. This proposed research offers engineering values for optimizing the machining parameters and improving the machining performances of micro EDM. 展开更多
关键词 Electrical Discharge Machining (EDM) micro EDM Scale effect similarity theory similarity evaluating method
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Similarity solutions of vertical plane wall plume based on finite analytic method 被引量:1
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作者 槐文信 曾玉红 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第4期447-454,共8页
The turbulent flow of vertical plane wall plume with concentration variation was studied with the finite analytical method. The k-epsilon model with the effect of buoyancy on turbulent kinetic energy and its dissipati... The turbulent flow of vertical plane wall plume with concentration variation was studied with the finite analytical method. The k-epsilon model with the effect of buoyancy on turbulent kinetic energy and its dissipation rate was adopted. There were similarity solutions in the uniform environment for the system of equations including the equation of continuity, the equation of momentum along the flow direction and concentration, and equations of k, epsilon. The finite analytic method was applied to obtain the similarity solution. The calculated data of velocity, relative density difference, the kinetic energy of turbulence and its dissipation rate distribution for vertical plane plumes are in good agreement with the experimental data at the turbulent Schmidt number equal to 1.0. The variations of their maximum value along the direction of main flow were also given. It shows that the present model is good, i.e., the effect of buoyancy on turbulent kinetic energy and its dissipation rate should be taken into account, and the finite analytic method is effective. 展开更多
关键词 wall plume similarity turbulence model finite analytic method buoyancy effect
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A weight's agglomerative method for detecting communities in weighted networks based on weight's similarity
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作者 沈毅 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期171-178,共8页
This paper proposes the new definition of the community structure of the weighted networks that groups of nodes in which the edge's weights distribute uniformly but at random between them. It can describe the steady ... This paper proposes the new definition of the community structure of the weighted networks that groups of nodes in which the edge's weights distribute uniformly but at random between them. It can describe the steady connections between nodes or some similarity between nodes' functions effectively. In order to detect the community structure efficiently, a threshold coefficient t~ to evaluate the equivalence of edges' weights and a new weighted modularity based on the weight's similarity are proposed. Then, constructing the weighted matrix and using the agglomerative mechanism, it presents a weight's agglomerative method based on optimizing the modularity to detect communities. For a network with n nodes, the algorithm can detect the community structure in time O(n2 log~). Simulations on networks show that the algorithm has higher accuracy and precision than the existing techniques. Furthermore, with the change of t~ the algorithm discovers a special hierarchical organization which can describe the various steady connections between nodes in groups. 展开更多
关键词 complex networks weight's similarity community structure weight's agglomerative method
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Formula for calculating spatial similarity degrees between point clouds on multi-scale maps taking map scale change as the only independent variable 被引量:5
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作者 Yang Weifang Yan Haowen Li Jonathan 《Geodesy and Geodynamics》 2015年第2期113-125,共13页
The degree of spatial similarity plays an important role in map generalization, yet there has been no quantitative research into it. To fill this gap, this study first defines map scale change and spatial similarity d... The degree of spatial similarity plays an important role in map generalization, yet there has been no quantitative research into it. To fill this gap, this study first defines map scale change and spatial similarity degree/relation in multi-scale map spaces and then proposes a model for calculating the degree of spatial similarity between a point cloud at one scale and its gener- alized counterpart at another scale. After validation, the new model features 16 points with map scale change as the x coordinate and the degree of spatial similarity as the y coordinate. Finally, using an application for curve fitting, the model achieves an empirical formula that can calculate the degree of spatial similarity using map scale change as the sole independent variable, and vice versa. This formula can be used to automate algorithms for point feature generalization and to determine when to terminate them during the generalization. 展开更多
关键词 Spatial similarity degree Map generalization Map scale change Point clouds Quantitative description Spatial similarity relations Multi-scale map spaces Curve fitting method
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Conditional Similarity Solutions of the Boussinesq Equation 被引量:6
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作者 TANGXiao-Yan LINJi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第4期399-404,共6页
The direct method proposed by Clarkson and Kruskal is modified to obtain some conditional similarity solutions of a nonlinear physics model. Taking the -dimensional Boussinesq equation as a simple example, six types o... The direct method proposed by Clarkson and Kruskal is modified to obtain some conditional similarity solutions of a nonlinear physics model. Taking the -dimensional Boussinesq equation as a simple example, six types of conditional similarity reductions are obtained. 展开更多
关键词 conditional similarity reduction direct method Boussinesq equation
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Conditional Similarity Reductions of Jimbo—Miwa Equation via the Classical Lie Group Approach 被引量:6
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作者 TANGXiao-Yan LINJi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第1期6-8,共3页
Recently, the Clarkson and Kruskal direct method has been modified to find new similarity reductions (conditional similarity reductions) of nonlinear systems and the results obtained by the modified direct method cann... Recently, the Clarkson and Kruskal direct method has been modified to find new similarity reductions (conditional similarity reductions) of nonlinear systems and the results obtained by the modified direct method cannot be obtained by the current classical and/or non-classical Lie group approach. In this paper, we show that the conditional similarity reductions of the Jimbo-Miwa equation can be reobtained by adding an additional constraint equation to the original model to form a conditional equation system first and then solving the model system by means of the classical Lie group approach. 展开更多
关键词 direct method Jimbo-Miwa equation conditional similarity reduction classical Lie group approach
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Discrepancy and Applicability of Various Similarity Functions in Flux Calculations Under Stable Conditions 被引量:1
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作者 郭晓峰 张宏升 +3 位作者 蔡旭晖 康凌 李万彪 杜金林 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第4期644-654,共11页
Based on data obtained during the Hualhe River Basin Experiment (HUBEX) in 1999, this study intends to detect the quantitative discrepancies in the momentum (τ0), sensible heat (H0) and latent heat (E0) fluxe... Based on data obtained during the Hualhe River Basin Experiment (HUBEX) in 1999, this study intends to detect the quantitative discrepancies in the momentum (τ0), sensible heat (H0) and latent heat (E0) fluxes among six sets of similarity functions with the aerodynamic method. It also aims to clarify the applicability of the functions under stable conditions. The relative discrepancy was studied with the normalized transfer coefficients for τ0, H0 and E0, namely CD, CH and CQ, respectively. Except for one set of functions that adopted a rather small von Kármán's constant (0.365), the relative discrepancy in τ0 among the other functions was less than 10%, while that in H0(E0) sometimes reached 25% when the bulk Richardson number (R/B) was less than 0.07. The absolute discrepancy in the fluxes was studied with statistical computations. Among the six sets of functions, the discrepancy in τ0, H0 and E0 sometimes reached 0.03 kg m^-1 s^-2, 4 W m^-2 and 10 W m^-2, respectively, and the discrepancy in the energy balance ratio sometimes exceeded 0.1. Furthermore, when RiB exceeded the critical value (Ric) for a specific set of functions, no fluxes could be derived with the functions. It is therefore suggested that RiB be compared with Ric before computing the fluxes if RiB is less than Ric. Finally, two sets of nonlinear similarity functions are recommended, due to their unlimited applicability in terms of RiB. 展开更多
关键词 aerodynamic method turbulent flux surface layer similarity function energy balance
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Clarkson-Kruskal Direct Similarity Approach for Differential-Difference Equations 被引量:2
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作者 SHEN Shou-Feng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6X期964-966,共3页
In this letter, the Clarkson-Kruskal direct method is extended to similarity reduce some differentialdifference equations. As examples, the differential-difference KZ equation and KP equation are considered.
关键词 differential-difference KZ equation differential-difference KP equation direct method similarity reduction
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SIMILARITY REDUCTIONS FOR 2+1-DIMENSIONAL VARIABLE COEFFICIENT GENERALIZED KADOMTSEV-PETVIASHVILI EQUATION 被引量:1
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作者 闫振亚 张鸿庆 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第6期645-650,共6页
With the aid of MATHEMATICA, the direct reduction method,vas extended and applied in 2 + 1-dimensional variable coefficient generalized Kadomtsev-Petviashvili equation( VCGRPE). As a result, several kinds of similarit... With the aid of MATHEMATICA, the direct reduction method,vas extended and applied in 2 + 1-dimensional variable coefficient generalized Kadomtsev-Petviashvili equation( VCGRPE). As a result, several kinds of similarity reductions for VCGKPE are obtained which contain Painleve I, Painleve II and Painleve ni reductions. 展开更多
关键词 variable coefficient generalized Kadomtsev- Petviashvili equation direct reduction method similarity reduction
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Computer Methodologies for the Comparison of Some Efficient Derivative FreeSimultaneous Iterative Methods for Finding Roots of Non-Linear Equations 被引量:1
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作者 Yuming Chu Naila Rafiq +3 位作者 Mudassir Shams Saima Akram Nazir Ahmad Mir Humaira Kalsoom 《Computers, Materials & Continua》 SCIE EI 2021年第1期275-290,共16页
In this article,we construct the most powerful family of simultaneous iterative method with global convergence behavior among all the existing methods in literature for finding all roots of non-linear equations.Conver... In this article,we construct the most powerful family of simultaneous iterative method with global convergence behavior among all the existing methods in literature for finding all roots of non-linear equations.Convergence analysis proved that the order of convergence of the family of derivative free simultaneous iterative method is nine.Our main aim is to check out the most regularly used simultaneous iterative methods for finding all roots of non-linear equations by studying their dynamical planes,numerical experiments and CPU time-methodology.Dynamical planes of iterative methods are drawn by using MATLAB for the comparison of global convergence properties of simultaneous iterative methods.Convergence behavior of the higher order simultaneous iterative methods are also illustrated by residual graph obtained from some numerical test examples.Numerical test examples,dynamical behavior and computational efficiency are provided to present the performance and dominant efficiency of the newly constructed derivative free family of simultaneous iterative method over existing higher order simultaneous methods in literature. 展开更多
关键词 non-linear equation iterative method simultaneous method basins of attractions computational efficiency
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Experimental and Numerical Study of Structural Identification Using Non-Linear Resonant Decay Method 被引量:1
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作者 Mehdi Sarmast Hamed Ghafari Jan R.Wright 《Sound & Vibration》 2019年第3期75-95,共21页
One of the practical approaches in identifying structures is the non-linear resonant decay method which identifies a non-linear dynamic system utilizing a model based on linear modal space containing the underlying li... One of the practical approaches in identifying structures is the non-linear resonant decay method which identifies a non-linear dynamic system utilizing a model based on linear modal space containing the underlying linear system and a small number of extra terms that exhibit the non-linear effects.In this paper,the method is illustrated in a simulated system and an experimental structure.The main objective of the non-linear resonant decay method is to identify the non-linear dynamic systems based on the use of a multi-shaker excitation using appropriated excitation which is obtained from the force appropriation approach.The experimental application of the method is indicated to provide suitable estimates of modal parameters for the identification of non-linear models of structures. 展开更多
关键词 non-linear modal identification non-linear dynamic system non-linear resonant decay method force appropriation approach
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Similarity Reductions of(2+1)-Dimensional Multi-component Broer-Kaup System 被引量:1
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作者 DONG Zhong-Zhou CHEN Yong WANG Ling 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期803-808,共6页
Painleve property of the (2+1)-dimensional multi-component Broer-Kaup (BK) system is considered by using the standard Weiss Kruskal approaches. Applying the Clarkson and Kruskal (CK) direct method to the (2+1... Painleve property of the (2+1)-dimensional multi-component Broer-Kaup (BK) system is considered by using the standard Weiss Kruskal approaches. Applying the Clarkson and Kruskal (CK) direct method to the (2+1)- dimensional multi-component BK system, some types of similarity reductions are obtained. By solving the reductions, one can get the solutions of the (2+1)-dimensional multi-component BK system. 展开更多
关键词 multi-component Broer Kaup system similarity reduction direct method
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Some Similarity Reduction Solutions to Two-Dimensional Incompressible Navier-Stokes Equation 被引量:1
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作者 JIAO Xiao-Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第9期389-394,共6页
We investigate the symmetry reduction for the two-dimensional incompressible Navier-Stokes equationin conventional stream function form through Lie symmetry method and construct some similarity reduction solutions.Two... We investigate the symmetry reduction for the two-dimensional incompressible Navier-Stokes equationin conventional stream function form through Lie symmetry method and construct some similarity reduction solutions.Two special cases in [D.K.Ludlow,P.A.Clarkson,and A.P.Bassom,Stud.Appl.Math.103 (1999) 183] and a theoremin [S.Y.Lou,M.Jia,X.Y.Tang,and F.Huang,Phys.Rev.E 75 (2007) 056318] are retrieved. 展开更多
关键词 Lie symmetry method Navier Stokes equation similarity reduction
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Conditional Similarity Solutions of (2+1)—Dimensional General nonintegrable KdV Equation 被引量:1
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作者 TANGXiao-Yan LOUSen-Yue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第2期139-144,共6页
The real physics models are usually quite complex with some arbitrary parameters which will lead to the nonintegrability of the model. To find some exact solutions of a nonintegrable model with some arbitrary paramete... The real physics models are usually quite complex with some arbitrary parameters which will lead to the nonintegrability of the model. To find some exact solutions of a nonintegrable model with some arbitrary parameters is much more difficult than to find the solutions of a model with some special parameters. In this paper, we make a modification for the usual direct method to find some conditional similarity solutions of a (2+1)-dimensional general nonintegrable KdV equation. 展开更多
关键词 similarity solutions modified direct method (2+1)-dimensional general KdV equation
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Double Elzaki Transform Decomposition Method for Solving Non-Linear Partial Differential Equations 被引量:1
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作者 Moh A. Hassan Tarig M. Elzaki 《Journal of Applied Mathematics and Physics》 2020年第8期1463-1471,共9页
In this paper, we discuss a new method employed to tackle non-linear partial differential equations, namely Double Elzaki Transform Decomposition Method (DETDM). This method is a combination of the Double ELzaki Trans... In this paper, we discuss a new method employed to tackle non-linear partial differential equations, namely Double Elzaki Transform Decomposition Method (DETDM). This method is a combination of the Double ELzaki Transform and Adomian Decomposition Method. This technique is hereafter provided and supported with necessary illustrations, together with some attached examples. The results reveal that the new method is very efficient, simple and can be applied to other non-linear problems. 展开更多
关键词 Double Elzaki Transform Adomian Decomposition method non-linear Partial Differential Equations
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A SIMILARITY SCHEME FOR QUANTITATIVE FORECAST OF PRECIPITATION OF TYPHOONS
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作者 钟元 潘劲松 +3 位作者 朱红 陈卫锋 陈世春 梁明珠 《Journal of Tropical Meteorology》 SCIE 2012年第3期322-331,共10页
A quantitative scheme is put forward in our work of forecasting the storm rainfall of typhoons for specific sites.Using the initial parameters,weather situations and physical quantities as well as numerical weather pr... A quantitative scheme is put forward in our work of forecasting the storm rainfall of typhoons for specific sites.Using the initial parameters,weather situations and physical quantities as well as numerical weather prediction products,the scheme constructs multivariate,objective and similarity criteria for environmental factors for the time between the current and forthcoming moment within the domain of forecast.Through defining a non-linear similarity index,this work presents a comprehensive assessment of the similarity between historical samples of typhoons and those being forecast in terms of continuous dynamic states under the multivariate criteria in order to identify similar samples.The historical rainfall records of the similar samples are used to run weighted summarization of the similarity index to determine site-specific and quantitative forecasts of future typhoon rainfall.Samples resembling the typhoon being forecast are selected by defining a non-linear similarity index composed of multiple criteria.Trial tests have demonstrated that this scheme has positive prediction skill. 展开更多
关键词 weather forecast forecasting methods typhoon storm precipitation site-specific and quantitative forecast similarity
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Similarity Reductions of Nonisospectral BKP Equation
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作者 YE Wang-Chuan LI Biao WANG Jia 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第10期565-571,共7页
Basing on the direct method developed by Clarkson and Kruskal,the nonisospectral BKP equation can bereduced to three types of(1+1)-dimensional variable coefficients partial differential equations(PDEs).Furthermore,ont... Basing on the direct method developed by Clarkson and Kruskal,the nonisospectral BKP equation can bereduced to three types of(1+1)-dimensional variable coefficients partial differential equations(PDEs).Furthermore,onthe basis of the idea of the symmetry group direct method by Lou et al.,three types of reduction PDEs are all reducedto the related constant coefficients PDEs by some transformations. 展开更多
关键词 nonisospectral BKP equation CK direct method similarity reductions
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