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Joint inversion of gravity and vertical gradient data based on modified structural similarity index for the structural and petrophysical consistency constraint
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作者 Sheng Liu Xiangyun Wan +6 位作者 Shuanggen Jin Bin Jia Quan Lou Songbai Xuan Binbin Qin Yiju Tang Dali Sun 《Geodesy and Geodynamics》 EI CSCD 2023年第5期485-499,共15页
Joint inversion is one of the most effective methods for reducing non-uniqueness for geophysical inversion.The current joint inversion methods can be divided into the structural consistency constraint and petrophysica... Joint inversion is one of the most effective methods for reducing non-uniqueness for geophysical inversion.The current joint inversion methods can be divided into the structural consistency constraint and petrophysical consistency constraint methods,which are mutually independent.Currently,there is a need for joint inversion methods that can comprehensively consider the structural consistency constraints and petrophysical consistency constraints.This paper develops the structural similarity index(SSIM)as a new structural and petrophysical consistency constraint for the joint inversion of gravity and vertical gradient data.The SSIM constraint is in the form of a fraction,which may have analytical singularities.Therefore,converting the fractional form to the subtractive form can solve the problem of analytic singularity and finally form a modified structural consistency index of the joint inversion,which enhances the stability of the SSIM constraint applied to the joint inversion.Compared to the reconstructed results from the cross-gradient inversion,the proposed method presents good performance and stability.The SSIM algorithm is a new joint inversion method for petrophysical and structural constraints.It can promote the consistency of the recovered models from the distribution and the structure of the physical property values.Then,applications to synthetic data illustrate that the algorithm proposed in this paper can well process the synthetic data and acquire good reconstructed results. 展开更多
关键词 Joint inversion Gravity and vertical gradient data Modified structural similarity index
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The Similar Structures and Control Problems of Complex Systems 被引量:1
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作者 张嗣瀛 《系统仿真学报》 CAS CSCD 2002年第11期1455-1457,共3页
In this paper, the naturally evolving complex systems, such as biotic and social ones, are considered. Focusing on their structures, a feature is noteworthy, i.e., the similarity in structures. The relations between t... In this paper, the naturally evolving complex systems, such as biotic and social ones, are considered. Focusing on their structures, a feature is noteworthy, i.e., the similarity in structures. The relations between the functions and behaviors of these systems and their similar structures will be studied. Owing to the management of social systems and the course of evolution of biotic systems may be regarded as control processes, the researches will be within the scope of control problems. Moreover, since it is difficult to model for biotic and social systems, it will start with the control problems of complex systems, possessing similar structures, in engineering. The obtained results show that for either linear or nonlinear systems and for a lot of control problems similar structures lead to a series of simplifications. In general, the original system may be decomposed into reduced amount of subsystems with lower dimensions and simpler structures. By virtue of such subsystems, the control problems of original system can be solved more simply. At last, it turns round to observe the biotic and social systems and some analyses are given. 展开更多
关键词 复杂系统 相似结构 可控制性
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A Structure Similarity Analysis Method for On-Line Recognition of Handwritten Chinese Characters
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作者 刘家锋 唐降龙 舒文豪 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1994年第1期51-54,共4页
AStructureSimilarityAnalysisMethodforOn-LineRecognitionofHandwrittenChineseCharactersLIUJiafeng;TANGJianglon... AStructureSimilarityAnalysisMethodforOn-LineRecognitionofHandwrittenChineseCharactersLIUJiafeng;TANGJianglong;SHUWenhao(刘家锋,唐... 展开更多
关键词 ss: ON-LINE RECOGNITION structural similarITY RADICAL
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THE STRUCTURE AND APPROXIMATION OF A.S. SELF-SIMILAR SET 被引量:1
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作者 胡迪鹤 《Acta Mathematica Scientia》 SCIE CSCD 2003年第2期201-207,共7页
The structure of any a.s. self-similar set K(w) generated by a class of random elements {gn,wσ} taking values in the space of contractive operators is given and the approximation of K(w) by the fixed points {Pn,wσ} ... The structure of any a.s. self-similar set K(w) generated by a class of random elements {gn,wσ} taking values in the space of contractive operators is given and the approximation of K(w) by the fixed points {Pn,wσ} of {gn,ow} is obtained. It is useful to generate the fractal in computer. 展开更多
关键词 a.s. self-similar set Hausdorff metric fixed point structure APPROXIMATION
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A Structure Similarity Analysis of Secreted Proteins in Magnaporthe oryzae and Its Host Oryza sativa
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作者 Wang Hui Su Yuan +3 位作者 Liu Chao Wang Yi Yang Jing Li Chengyun 《Plant Diseases and Pests》 CAS 2017年第2期26-33,共8页
The structure similarity of secreted proteins in rice blast fungus Magnaporthe oryzae and its host Oryza sativa was analyzed. One thousand two hundred and forty one proteins were predicted as secreted proteins using f... The structure similarity of secreted proteins in rice blast fungus Magnaporthe oryzae and its host Oryza sativa was analyzed. One thousand two hundred and forty one proteins were predicted as secreted proteins using four algorithms based on 11 074 proteins in genome of M. oryzae. One hundred and forty six secreted proteins( 11. 8% of M. oryzae secretome) were aligned with 116 rice proteins( 0. 21% of 56 278 rice proteins) using BLAST search on rice genome. One hundred sixteen rice similar proteins participated in rice cell wall modification( cell wall associated enzymes) and signal transduction( proteases). These results imply that both cell wall involved proteins and signal transduction are probably hijacks pathway between host pants and pathogenic fungi. Because these proteins are highly conserved among fungi and plants,the express patterns of these protein coding genes during the interaction process are valuable to study in detail. 展开更多
关键词 Blast fungus RICE Secreted protein structure similarity
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SIMILARITY TRANSFORMATION, THE STRUCTURE OF THE TRAVELING WAVES SOLUTION AND THE EXISTENCE OF A GLOBAL SMOOTH SOLUTION TO GENERALIZED KURAMOTO SIVASHINSKY TYPE EQUATIONS
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作者 郭柏灵 潘兴德 《Acta Mathematica Scientia》 SCIE CSCD 1991年第1期48-55,共8页
The existence of a global smooth solution for the initial value problem of generalized Kuramoto-Sivashinsky type equations have been obtained. Similarty siolutions and the structure of the traveling waves solution for... The existence of a global smooth solution for the initial value problem of generalized Kuramoto-Sivashinsky type equations have been obtained. Similarty siolutions and the structure of the traveling waves solution for the generalized KS equations are discussed and analysed by using the qualitative theory of ODE and Lie's infinitesimal transformation respectively. 展开更多
关键词 similarITY TRANSFORMATION THE structure OF THE TRAVELING WAVES SOLUTION AND THE EXISTENCE OF A GLOBAL SMOOTH SOLUTION TO GENERALIZED KURAMOTO SIVASHINSKY TYPE EQUATIONS
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Reconfigurable Modeling Technology of Similar-structure Products Configuration Design
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作者 QIU Lemiao REN Bin +1 位作者 ZHANG Shuyou XU Jian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第1期189-196,共8页
The product configuration modeling is a key technology to realize configuration design. Most of the researches were mainly conducted focusing on how to establish a product configuration model, but were short of the co... The product configuration modeling is a key technology to realize configuration design. Most of the researches were mainly conducted focusing on how to establish a product configuration model, but were short of the consideration about the application scope and dynamic change features. In this paper, the reconfigurable modeling technology of similar-structure products configuration design is studied to enhance the generality and diversity of product configuration models, and to facilitate the dynamic upgrade of configuration models. The configuration components of products with similar structures are divided into sharable configuration components, essential configuration components and optional configuration components, so the construction of reconfigurable model of configuration design can be converted into the set operation of configuration components. The horizontal adjusting reconstruction of configuration model is carried out through the adding, replacing and deleting of configuration components, the vertical adjusting reconstruction of configuration model is carried out through the parametric deformation of configuration components, and the variable topological configuration model reconstruction can be realized through the transformation of partial structure of configuration components. Finally, NC machine products are used as an example to analyze and verify the reconfigurable modeling technology of products with similar structures. The speed of NC machine configuration design is found to be improved, and the number of NC machine configuration design models is decreased. And the reconfigurable design system of NC machine products is developed. The proposed modeling technology provides references for the processes, methods and steps of model reconstruction. 展开更多
关键词 similar-structure products configuration component product configuration model RECONSTRUCTION
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Self-Similar Characteristic for the Ramp Structures of Wind Speed
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作者 SONG Zong-Peng HU Fei +1 位作者 XU Jing-Jing CHENG Xue-Ling 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第4期320-323,共4页
Time series of wind speed are composed of large and small ramp structures. Data analysis reveals a power law relation between the linear slope of ramp structures and the time scale. This suggests that these ramp struc... Time series of wind speed are composed of large and small ramp structures. Data analysis reveals a power law relation between the linear slope of ramp structures and the time scale. This suggests that these ramp structures of wind speed have a self-similar characteristic. The lower limit of the self-similar scale range was 2 s. The upper limit is unexpectedly large at 27 min. Data are collected from grassland, city, and lake areas. Although these data have different underlying surfaces, all of them clearly show a power law relation, with slight differences in their power exponents. 展开更多
关键词 自相似特性 斜坡结构 风速 幂律关系 时间序列 数据分析 时间尺度 相似特征
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Modeling of 3D-structure for regular fragments of low similarity unknown structure proteins
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作者 彭志红 Chen Jie Lin Xiwen Sang Yanchao 《High Technology Letters》 EI CAS 2007年第4期431-435,共5页
关键词 3D结构模型 计算机模拟 相似性 技术性能
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TOPSIS with Belief Structure for Group Belief Multiple Criteria Decision Making 被引量:1
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作者 Jiang Jiang Ying-Wu Chen +1 位作者 Da-Wei Tang Yu-Wang Chen 《International Journal of Automation and computing》 EI 2010年第3期359-364,共6页
The technique for order performance by similarity to ideal solution (TOPSIS) is one of the major techniques in dealing with multiple criteria decision making (MCDM) problems, and the belief structure (BS) model ... The technique for order performance by similarity to ideal solution (TOPSIS) is one of the major techniques in dealing with multiple criteria decision making (MCDM) problems, and the belief structure (BS) model has been used successfully for uncertain MCDM with incompleteness, impreciseness or ignorance. In this paper, the TOPSIS method with BS model is proposed to solve group belief MCDM problems. Firstly, the group belief MCDM problem is structured as a belief decision matrix in which the judgments of each decision maker are described as BS models, and then the evidential reasoning approach is used for aggregating the multiple decision makers' judgments. Subsequently, the positive and negative ideal belief solutions are defined with the principle of TOPSIS. To measure the separation from ideal solutions, the concept and algorithm of belief distance measure are defined, which can be used for comparing the difference between BS models. Finally, the relative closeness and ranking index are calculated for ranking the alternatives. A numerical example is given to illustrate the proposed method. 展开更多
关键词 Multiple criteria decision making (MCDM) technique for order performance by similarity to ideal solution (TOPSIS) belief structure (BS) model group decision making belief distance measure.
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Physical Modeling of Influence of Rock Mass Structure on Roof Stability
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作者 孟召平 彭苏萍 +1 位作者 尹尚先 王磊 《International Journal of Mining Science and Technology》 SCIE EI 2000年第2期67-71,共5页
Based on the developing degree of structure planes in coal roof, whole, blocky and heavily fractured structure models are built up. Through simulation test of similar materials, the distribution of deformation, failur... Based on the developing degree of structure planes in coal roof, whole, blocky and heavily fractured structure models are built up. Through simulation test of similar materials, the distribution of deformation, failure and underground pressure induced by coal mining in coal roof with different rock mass structures are analyzed. The test results indicate that the distances of first and periodic weighting of main roof and the height of caving and fracture zone decrease with the increment of fractures in roof rock mass. From whole to blocky and heavily fractured structures, abutment pressure ahead of working face reduces and the peak value of abutment pressure migrates to inside of roof rock mass. 展开更多
关键词 ROCK MASS structure ROOF STABILITY similar simulation test
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The similitude research on underwater complex shell-structure based on SEA 被引量:1
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作者 WANGSan-de YANGDe-sen SHISheng-guo FANGEr-zheng 《Journal of Marine Science and Application》 2005年第1期54-59,共6页
In this paper, the vibration and sound radiation of the underwater complex shell-structure which is the cylindrical shell with hemi-spherical shell on the ends are studied by statistical energy analysis (SEA). The who... In this paper, the vibration and sound radiation of the underwater complex shell-structure which is the cylindrical shell with hemi-spherical shell on the ends are studied by statistical energy analysis (SEA). The whole shell-structure is divided into the four subsystems, and the SEA physical model and power flow balance equations among these subsystems are established. The similitude relations of input power, coupling loss factor and modal density of the subsystems between the complex shell-structure and its scaled-down model are analyzed. According to the similitude theory and power flow balance equations, when the immerged shell-structures are excited, the similar relations of spatially averaged vibration response and underwater radiating sound power are established for the complex shell-structure and its scaled-down model. 展开更多
关键词 SEA 相似关系 声波辐射 结构振动
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Systematic Method of Applying Structural Characteristics of Natural Organisms to Mechanical Structures 被引量:1
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作者 行登海 陈五一 《Transactions of Tianjin University》 EI CAS 2011年第4期293-297,共5页
Structural bionic design lacks mature and scientific theories, and the excellent structural characteristics of natural organisms sometimes cannot be transferred into engineering structures effectively. Aiming at overc... Structural bionic design lacks mature and scientific theories, and the excellent structural characteristics of natural organisms sometimes cannot be transferred into engineering structures effectively. Aiming at overcoming the existing problems, this paper summarizes three related theories: similarity theory, fuzzy evaluation theory and optimization theory. Based on the related theories, a method of structural bionic design is introduced, which includes four steps: selecting the most useful structural characteristic of natural organism; analyzing the structural characteristic finally chosen for engineering problem; completing the structural bionic design for engineering structure; and verifying the structural bionic design. Similarity theory and fuzzy evaluation theory are employed to achieve Step 1. In Step 2 and Step 3, optimization theory is employed to analyze the parameters of structures. Together with the thoughts of simplification and grouping, optimization theory can reveal the relationship between organism structure and engineering structure, providing a way to structural bionic design. A general evaluation criterion is proposed in Step 4, which is feasible to evaluate the performance of different structures. Finally, based on the method, a structural bionic design of thin-walled cylindrical shell is introduced. 展开更多
关键词 机械结构 生物 自然 模糊评价理论 仿生设计 最优化理论 系统 工程结构
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Three-Dimensional Shaking Table Test of 1/10 Scale Model of Reinforced Concrete Frame Structure
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作者 LIU Tao, ZhANG Zhi-mei, XIE Li-min Department of Civil Engineering, Shanghai University Shanghai 200072, China Shenzhen Laiyingda Industry and Trade Co. Ltd, Shenzhen 518020, China 《Advances in Manufacturing》 SCIE CAS 2000年第S1期21-24,共4页
A l/10 scale model of reinforced concrete (R C ) frame structure was tested on the 15t-shaking table of State Key Laboratory, Tongji University The structural prototype was a 10-storey office building that was damag... A l/10 scale model of reinforced concrete (R C ) frame structure was tested on the 15t-shaking table of State Key Laboratory, Tongji University The structural prototype was a 10-storey office building that was damaged in the 1985 Mexico major earthquake[1] The original acceleration records in the earthquake were applied as the input waves in the test The dynamical test model was designed according to the general law of similarity, and the effect of the shortage of artificial quality was considered The model was carefully made of fine gravel concrete and galvanized iron wire The damage of test model is in good agreement with that of archetypal building in the experiment 展开更多
关键词 R C frame structure shaking table law of similarity
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Color Image Quality Assessment Based on Structural Similarity 被引量:2
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作者 卢芳芳 赵群飞 杨根科 《Journal of Donghua University(English Edition)》 EI CAS 2010年第4期443-450,共8页
It is well-known that classical quality measures,such as Mean Squared Error(MSE),Weighted Mean Squared Error(WMSE)or Peak Signal-to-Noise Ratio(PSNR),are not always corresponding with visual observations.Structural si... It is well-known that classical quality measures,such as Mean Squared Error(MSE),Weighted Mean Squared Error(WMSE)or Peak Signal-to-Noise Ratio(PSNR),are not always corresponding with visual observations.Structural similarity based image quality assessment was proposed under the assumption that the Human Visual System(HVS)is highly adapted for extracting structural information from an image.While the demand on high color quality increases in the media industry,color loss will make the visual quality different.In this paper,we proposed an improved quality assessment(QA)method by adding color comparison into the structural similarity(SSIM)measurement system for evaluating color image quality.Then we divided the task of similarity measurement into four comparisons:luminance,contrast,structure,and color.Experimental results show that the predicted quality scores of the proposed method are more effective and consistent with visual quality than the classical methods using five different distortion types of color image sets. 展开更多
关键词 图象质量评价 结构的类似 差别平均数意见 20 颜色图象
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Characterization of the sequence spectrum of DNA based on the appearance frequency of the nucleotide sequences of the genome——A new method for analysis of genome structure 被引量:3
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作者 Masatoshi Nakahara Masaharu Takeda 《Journal of Biomedical Science and Engineering》 2010年第4期340-350,共11页
The nucleotide (base) sequence of the genome might reflect biological information beyond the coding sequences. The appearance frequencies of successive base sequences (key sequences) were calculated for entire genomes... The nucleotide (base) sequence of the genome might reflect biological information beyond the coding sequences. The appearance frequencies of successive base sequences (key sequences) were calculated for entire genomes. Based on the appearance frequency of the key sequences of the genome, any DNA sequences on the genome could be expressed as a sequence spectrum with the adjoining base sequences, which could be used to study the corresponding biological phenomena. In this paper, we used 64 successive three- base sequences (triplets) as the key sequences, and determined and compared the spectra of specific genes to the chromosome, or specific genes to tRNA genes in Saccharomyces cerevisiae, Schizosaccharomyces pombe and Escherichia coli. Based on these analyses, a gene and its corresponding position on the chromosome showed highly similar spectra with the same fold enlargement (approximately 400-fold) in the S. cerevisiae, S. pombe and E. coli genomes. In addition, the homologous structure of genes that encode proteins was also observed with appropriate tRNA gene(s) in the genome. This analytical method might faithfully reflect the encoded biological information, that is, the conservation of the base sequences was to make sense the conservation of the translated amino acids sequence in the coding region, and might be universally applicable to other genomes, even those that consisted of multiple chromosomes. 展开更多
关键词 APPEARANCE FREQUENCY of TRIPLET in GENOME Base SEQUENCE SELF-similarITY Analytical Method of GENOME structure
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Structure of Halo Nuclei 被引量:1
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作者 Wang, Zhengda Zhang, Xiaodong +1 位作者 Wang, Xiaochun Wang, Xiaobin 《Chinese journal of nuclear physics》 EI 1995年第2期137-141,共5页
A self-similar-structure shell modct (SSM) is proposed to extend the conven-tional shell model (SM) calculation to study halo nuclei.The exotic structures of <sup>11</sup>Liand <sup>6</sup>... A self-similar-structure shell modct (SSM) is proposed to extend the conven-tional shell model (SM) calculation to study halo nuclei.The exotic structures of <sup>11</sup>Liand <sup>6</sup>He nuclei are reproduced by means of SSM.The neutron halo of <sup>11</sup>Li comes fromthe spin-orbit term and the thick neutron skin of <sup>6</sup>He arises from the different quantumnumbers N<sub>n</sub> and N<sub>p</sub>(N=2n+1) in SSM. 展开更多
关键词 Self-similar-structure shell model HALO NUCLEI HARMONIC OSCILLATOR
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A Novel Prediction Method of Protein Structural Classes Based on Protein Super-Secondary Structure
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作者 Longlong Liu Jing Cui Jie Zhou 《Journal of Computer and Communications》 2016年第15期54-62,共10页
At present, the feature extraction of protein sequences is the most basic issue to predict protein structural classes and is also the key problem to decide the quality of prediction. In order to predict protein struct... At present, the feature extraction of protein sequences is the most basic issue to predict protein structural classes and is also the key problem to decide the quality of prediction. In order to predict protein structural classes accurately, we construct a 14-dimensional feature vector based on protein secondary and super-secondary structure information to reflect the content and spatial ordering of the given protein sequences. Among the vector, seven features about -helix bundle, hairpin motifs, Rossman folds, -plaits and other super-secondary structure information are first proposed in our paper. Experiments show that our method improves overall accuracy of lower similarity datasets 1189 and 640 by 0.9% - 3.8% and 0.5% - 4.2% respectively compared with other methods and has a competitive advantage for predicting proteins in and classes. 展开更多
关键词 PROTEINS Super-Secondary structure Low similarity New Features
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Fully Nonlinear Simulation for Fluid/Structure Impact:A Review 被引量:2
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作者 Shili Sun Guoxiong Wu 《Journal of Marine Science and Application》 2014年第3期237-244,共8页
这篇论文基于 inviscid 和 imcompressible 液体和无旋的流动在液体 / 结构影响上论述工作的评论。焦点在和边界元素方法(BEM ) 的速度潜力理论上。充分非线性的边界条件在未知免费表面和动人的身体的弄湿的表面上被强加。评论包括(1 )... 这篇论文基于 inviscid 和 imcompressible 液体和无旋的流动在液体 / 结构影响上论述工作的评论。焦点在和边界元素方法(BEM ) 的速度潜力理论上。充分非线性的边界条件在未知免费表面和动人的身体的弄湿的表面上被强加。评论包括(1 ) 在常数或规定变化速度的身体的垂直、倾斜的水入口,以及免费秋天运动,(2 ) 液体微滴或列影响以及波浪影响身体,(3 ) 膨胀身体的类似答案。它盖住二维(2D ) , axisymmetric 并且三维(3D ) 盒子。在数字模拟使用的关键技术被构画出,包括 multivalued 上的网孔产生免费表面,为扩展域的拉长的坐标系统,压力的相互的依赖和身体打手势的为去耦的辅助函数方法,并且为喷气或薄液体电影的处理在影响期间发展了。 展开更多
关键词 结构影响 拟流体 非线性模 自由落体运动 非线性边界条件 展望 自由表面 液体薄膜
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Hidden Properties of Mathematical Physics Equations. Double Solutions. The Realization of Integrable Structures. Emergence of Physical Structures and Observable Formations
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作者 L. I. Petrova 《Journal of Applied Mathematics and Physics》 2020年第7期1255-1262,共8页
With the help of skew-symmetric differential forms the hidden properties of the mathematical physics equations are revealed. It is shown that the equations of mathematical physics can describe the emergence of various... With the help of skew-symmetric differential forms the hidden properties of the mathematical physics equations are revealed. It is shown that the equations of mathematical physics can describe the emergence of various structures and formations such as waves, vortices, turbulent pulsations and others. Such properties of the mathematical physics equations, which are hidden (they appear only in the process of solving these equations), depend on the consistency of derivatives in partial differential equations and on the consistency of equations, if the equations of mathematical physics are a set of equations. This is due to the integrability of mathematical physics equations. It is shown that the equations of mathematical physics can have double solutions, namely, the solutions on the original coordinate space and the solutions on integrable structures that are realized discretely (due to any degrees of freedom). The transition from the solutions of the first type to one of the second type describes discrete transitions and the processes of origin of various structures and observable formations. Only mathematical physics equations, on what no additional conditions such as the integrability conditions are imposed, can possess such properties. The results of the present paper were obtained with the help of skew-symmetric differential forms. 展开更多
关键词 Integrability of Mathematical Physics Equations Double Solutions Integrable structures Discrete Transitions skew-symmetric Differential Forms
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