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General laws of funding for scientific citations:how citations change in funded and unfunded research between basic and applied sciences 被引量:1
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作者 Mario Coccia Saeed Roshani 《Journal of Data and Information Science》 CSCD 2024年第4期71-89,共19页
Purpose:The goal of this study is to analyze the relationship between funded and unfunded papers and their citations in both basic and applied sciences.Design/methodology/approach:A power law model analyzes the relati... Purpose:The goal of this study is to analyze the relationship between funded and unfunded papers and their citations in both basic and applied sciences.Design/methodology/approach:A power law model analyzes the relationship between research funding and citations of papers using 831,337 documents recorded in the Web of Science database.Findings:The original results reveal general characteristics of the diffusion of science in research fields:a)Funded articles receive higher citations compared to unfunded papers in journals;b)Funded articles exhibit a super-linear growth in citations,surpassing the increase seen in unfunded articles.This finding reveals a higher diffusion of scientific knowledge in funded articles.Moreover,c)funded articles in both basic and applied sciences demonstrate a similar expected change in citations,equivalent to about 1.23%,when the number of funded papers increases by 1%in journals.This result suggests,for the first time,that funding effect of scientific research is an invariant driver,irrespective of the nature of the basic or applied sciences.Originality/value:This evidence suggests empirical laws of funding for scientific citations that explain the importance of robust funding mechanisms for achieving impactful research outcomes in science and society.These findings here also highlight that funding for scientific research is a critical driving force in supporting citations and the dissemination of scientific knowledge in recorded documents in both basic and applied sciences.Practical implications:This comprehensive result provides a holistic view of the relationship between funding and citation performance in science to guide policymakers and R&D managers with science policies by directing funding to research in promoting the scientific development and higher diffusion of results for the progress of human society. 展开更多
关键词 Research funding CITATIONS Scientific development Science diffusion Scientific laws Power law model Matthew effect Science policy Research policy Science of science Dynamics of science Evolution of science
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基于多尺度Laws纹理能量和低秩分解的织物疵点检测算法
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作者 王振华 张周强 +1 位作者 昝杰 刘江浩 《纺织学报》 EI CAS CSCD 北大核心 2024年第4期96-104,共9页
为提高织物疵点检测算法对简单纹理织物、模式纹理织物及条纹纹理织物检测时的普适性和准确性,提出了一种基于多尺度Laws纹理能量和低秩分解的织物疵点检测算法。首先,对织物图像进行直方图均衡化并将处理后的图像均匀划分为子图像块;其... 为提高织物疵点检测算法对简单纹理织物、模式纹理织物及条纹纹理织物检测时的普适性和准确性,提出了一种基于多尺度Laws纹理能量和低秩分解的织物疵点检测算法。首先,对织物图像进行直方图均衡化并将处理后的图像均匀划分为子图像块;其次,对每个子图像块提取28个纹理能量特征(利用7个Laws滤波模板在4个尺度上提取),计算所有子图像块提取到的特征均值并组成特征矩阵;然后,利用特征矩阵构建低秩分解模型,通过方向交替方法(ADM)优化求解,得到低秩部分和稀疏部分;最后,由稀疏部分生成疵点显著图,采用迭代阈值分割法对其进行分割,得到织物疵点检测结果。为验证该算法的有效性,在织物图像数据集选取了包含错纬、断经、跳花、破洞等常见疵点的织物图像,并将实验结果与已有3种算法进行了对比。实验结果表明,该算法在简单纹理织物、模式纹理织物及条纹纹理织物检测上具有更好的普适性和准确性,且检测效率具有一定优势。 展开更多
关键词 织物疵点 疵点检测 laws纹理 纹理能量 特征提取 矩阵低秩分解
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Scaling Laws Behind Penetrative Turbulence:History and Perspectives
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作者 Zijing DING Ruiqi HUANG Zhen OUYANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期1881-1900,共20页
An unstably stratified flow entering into a stably stratified flow is referred to as penetrative convection,which is crucial to many physical processes and has been thought of as a key factor for extreme weather condi... An unstably stratified flow entering into a stably stratified flow is referred to as penetrative convection,which is crucial to many physical processes and has been thought of as a key factor for extreme weather conditions.Past theoretical,numerical,and experimental studies on penetrative convection are reviewed,along with field studies providing insights into turbulence modeling.The physical factors that initiate penetrative convection,including internal heat sources,nonlinear constitutive relationships,centrifugal forces and other complicated factors are summarized.Cutting-edge methods for understanding transport mechanisms and statistical properties of penetrative turbulence are also documented,e.g.,the variational approach and quasilinear approach,which derive scaling laws embedded in penetrative turbulence.Exploring these scaling laws in penetrative convection can improve our understanding of large-scale geophysical and astrophysical motions.To better the model of penetrative turbulence towards a practical situation,new directions,e.g.,penetrative convection in spheres,and radiation-forced convection,are proposed. 展开更多
关键词 thermal convection penetrative convection scaling law TURBULENCE
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Nonuniform Dependence on the Initial Data for Solutions of Conservation Laws
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作者 John M.Holmes Barbara Lee Keyfitz 《Communications on Applied Mathematics and Computation》 EI 2024年第1期489-500,共12页
In this paper,we study systems of conservation laws in one space dimension.We prove that for classical solutions in Sobolev spaces H^(s),with s>3/2,the data-to-solution map is not uniformly continuous.Our results a... In this paper,we study systems of conservation laws in one space dimension.We prove that for classical solutions in Sobolev spaces H^(s),with s>3/2,the data-to-solution map is not uniformly continuous.Our results apply to all nonlinear scalar conservation laws and to nonlinear hyperbolic systems of two equations. 展开更多
关键词 Conservation laws Data-to-solution map Nonuniform dependence
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Literature overview of basic characteristics and flotation laws of flocs
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作者 Wanzhong Yin Yu Xie Zhanglei Zhu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期943-958,共16页
Flocculation flotation is the most efficient method for recovering fine-grained minerals,and its essence lies in flotation and recovery of flocs.Fundamental physical characteristics of flocs are mainly determined by t... Flocculation flotation is the most efficient method for recovering fine-grained minerals,and its essence lies in flotation and recovery of flocs.Fundamental physical characteristics of flocs are mainly determined by their apparent particle size and structure(density and morphology).Substantial researches have been conducted regarding the effect of floc characteristics on particle settling and water treatment.However,the influence of floc characteristics on flotation has not been widely studied.Based on the floc formation and flocculation flotation,this study reviews the fundamental physical characteristics of flocs from the perspectives of floc particle size and structure,summarizing the interaction between floc particle size and structure.Moreover,it thoroughly discusses the effect of floc particle size and structure on floc floatability,further revealing the influence of floc characteristics on bubble collision and adhesion and elucidating the mechanisms of interaction between flocs and bubbles.Thus,it is observed that floc particle size is not the only factor influencing flocculation flotation.Within the appropriate apparent particle size range,flocs with a compact structure exhibit higher efficiency in bubble collision and adhesion during flotation,thereby resulting in enhanced flotation performance.This study aims to provide a reference for flocculation flotation,targeting the development of more efficient and refined flocculation flotation processes in the future. 展开更多
关键词 FLOCS basic characteristics particle size and structure flotation laws BUBBLES
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Dimension by Dimension Finite Volume HWENO Method for Hyperbolic Conservation Laws
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作者 Feng Zheng Jianxian Qiu 《Communications on Applied Mathematics and Computation》 EI 2024年第1期605-624,共20页
In this paper,we propose a finite volume Hermite weighted essentially non-oscillatory(HWENO)method based on the dimension by dimension framework to solve hyperbolic conservation laws.It can maintain the high accuracy ... In this paper,we propose a finite volume Hermite weighted essentially non-oscillatory(HWENO)method based on the dimension by dimension framework to solve hyperbolic conservation laws.It can maintain the high accuracy in the smooth region and obtain the high resolution solution when the discontinuity appears,and it is compact which will be good for giving the numerical boundary conditions.Furthermore,it avoids complicated least square procedure when we implement the genuine two dimensional(2D)finite volume HWENO reconstruction,and it can be regarded as a generalization of the one dimensional(1D)HWENO method.Extensive numerical tests are performed to verify the high resolution and high accuracy of the scheme. 展开更多
关键词 Finite volume Dimension by dimension HWENO Hyperbolic conservation laws
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On the Use of Monotonicity-Preserving Interpolatory Techniques in Multilevel Schemes for Balance Laws
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作者 Antonio Baeza Rosa Donat Anna Martinez-Gavara 《Communications on Applied Mathematics and Computation》 EI 2024年第2期1319-1341,共23页
Cost-effective multilevel techniques for homogeneous hyperbolic conservation laws are very successful in reducing the computational cost associated to high resolution shock capturing numerical schemes.Because they do ... Cost-effective multilevel techniques for homogeneous hyperbolic conservation laws are very successful in reducing the computational cost associated to high resolution shock capturing numerical schemes.Because they do not involve any special data structure,and do not induce savings in memory requirements,they are easily implemented on existing codes and are recommended for 1D and 2D simulations when intensive testing is required.The multilevel technique can also be applied to balance laws,but in this case,numerical errors may be induced by the technique.We present a series of numerical tests that point out that the use of monotonicity-preserving interpolatory techniques eliminates the numerical errors observed when using the usual 4-point centered Lagrange interpolation,and leads to a more robust multilevel code for balance laws,while maintaining the efficiency rates observed forhyperbolic conservation laws. 展开更多
关键词 Hyperbolic balance laws Well-balanced schemes Multilevel schemes Harten's multiresolution
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基于Laws与Gabor滤波的田间西兰花花球识别技术 被引量:3
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作者 赵雄 徐港吉 +2 位作者 陈建能 俞高红 代丽 《农业机械学报》 EI CAS CSCD 北大核心 2023年第4期313-322,共10页
正确识别西兰花田间位置是实现西兰花自动化采收的基础,西兰花花球颜色与植株的叶片、茎秆相似,仅通过颜色特征无法对西兰花进行识别,本文以成熟期的田间西兰花为研究对象,提出了一种基于纹理特征与颜色特征的西兰花识别算法。首先通过... 正确识别西兰花田间位置是实现西兰花自动化采收的基础,西兰花花球颜色与植株的叶片、茎秆相似,仅通过颜色特征无法对西兰花进行识别,本文以成熟期的田间西兰花为研究对象,提出了一种基于纹理特征与颜色特征的西兰花识别算法。首先通过预处理以及Laws滤波对图像进行边界纹理强化,再通过Gabor滤波对图像进行纹理特征向量提取,并对提取后的纹理特征向量进行z⁃score标准化,随后对标准化后的纹理特征向量进行K⁃means聚类与开运算,获取花球潜在存在区域。同时对RGB图像进行HSV转换,通过对图像的H分量进行阈值分割达到滤除地面像素的效果。最终对纹理特征识别与颜色特征识别的结果进行融合,实现对田间西兰花的识别。算法通过结合纹理与颜色特征,对田间西兰花进行了识别,解决了西兰花的花球与茎叶等背景颜色相近难以识别的问题。本文共使用792幅图像进行试验,试验结果表明,本方法可以准确地对西兰花田间图像进行识别,其精确率为96.96%,召回率为94.41%,F1值为95.67%。通过对3组不同拍摄环境的数据集进行算法识别,3组数据集的F1值始终保持在94%以上,具有良好的拍摄环境适应性,为农业机器人进行西兰花自动化采收奠定了基础。 展开更多
关键词 图像识别 西兰花 纹理强化 laws滤波 GABOR滤波
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基于小波变换的Laws纹理测度在植被分割中的应用 被引量:7
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作者 张崚 路威 管华 《大学数学》 北大核心 2005年第2期5-9,共5页
针对从全色航空影像中进行植被区域提取的随机性和复杂性,阐述了一种基于小波的Laws纹理测度进行植被提取的新算法,它的特点是先用小波变换将图像变换到不同的尺度层上,然后再在多尺度层上提取Laws纹理测度,形成植被区域的特征.与传统... 针对从全色航空影像中进行植被区域提取的随机性和复杂性,阐述了一种基于小波的Laws纹理测度进行植被提取的新算法,它的特点是先用小波变换将图像变换到不同的尺度层上,然后再在多尺度层上提取Laws纹理测度,形成植被区域的特征.与传统的植被提取方法比,它用到了不同频率上纹理的Laws信息,从而更准确的刻画了植被区域的纹理特征,试验结果表明:基于小波变换的Laws纹理测度对植被有较好的分割效果. 展开更多
关键词 小波变换 laws纹理测度 图像分割
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基于Laws能量和变化频次的伪装色移动目标检测 被引量:4
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作者 李金屏 李倩 《中国体视学与图像分析》 2011年第1期18-23,共6页
动态背景下的移动目标检测是视频监控的研究热点之一,具有伪装色的移动目标检测是其中的一个难点。传统的高斯混合模型不适合检测这类移动目标。通过分析动态背景下具有伪装色移动目标的颜色变化规律,提出了利用Laws能量和一种称为变化... 动态背景下的移动目标检测是视频监控的研究热点之一,具有伪装色的移动目标检测是其中的一个难点。传统的高斯混合模型不适合检测这类移动目标。通过分析动态背景下具有伪装色移动目标的颜色变化规律,提出了利用Laws能量和一种称为变化频次的特殊统计量的检测方法。实验表明,该方法能够有效地检测某些动态背景下一些具有伪装色的移动目标,即在摄像头固定情况下,对于平缓变化的动态背景中颜色变化幅度较大或者表面纹理复杂的具有伪装色的移动目标,该方法具有良好的检测效果。 展开更多
关键词 动态背景 伪装色 移动目标检测 laws能量 变化频次
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Laws纹理能量结合灰度共生矩阵的遥感影像面状地物提取 被引量:8
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作者 李光 姜春雪 +1 位作者 刘争战 王立伟 《测绘与空间地理信息》 2017年第7期179-181,185,共4页
针对遥感影像中纹理较复杂的面状地物提取问题,提出一种Laws纹理能量结合灰度共生矩阵的遥感影像面状地物提取方法。该方法首先利用数学形态学膨胀、腐蚀对影像进行预处理;然后,分别对影像进行直方图均衡化,利用4个微观滤波算子滤波生成... 针对遥感影像中纹理较复杂的面状地物提取问题,提出一种Laws纹理能量结合灰度共生矩阵的遥感影像面状地物提取方法。该方法首先利用数学形态学膨胀、腐蚀对影像进行预处理;然后,分别对影像进行直方图均衡化,利用4个微观滤波算子滤波生成4幅微纹理影像;计算影像4个方向灰度共生矩阵及每个共生矩阵的4个纹理测度,生成4幅纹理影像;最后,结合8幅纹理影像进行区域生长跟踪轮廓。 展开更多
关键词 面状地物提取 laws纹理能量 灰度共生矩阵 纹理影像 区域生长
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Primary Research on WSeveral Theorems,Laws and Corollaries of Hydrology 被引量:2
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作者 龚云 《Agricultural Science & Technology》 CAS 2009年第4期1-3,54,共4页
The conceptions of theorems, laws and corollaries of hydrology were put forward. Combining with hydrology practice, several theo- rems, laws as well as corollaries of hydrology were summarized. The study provided some... The conceptions of theorems, laws and corollaries of hydrology were put forward. Combining with hydrology practice, several theo- rems, laws as well as corollaries of hydrology were summarized. The study provided some references for accelerating the development of hydrology theory in these aspects and promoting the improvement of its production technology. 展开更多
关键词 HYDROLOGY THEOREM law Corollary
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Regional epidemic laws of poplar Ice Nucleation Active bacterial canker 被引量:1
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作者 董爱荣 项存悌 +6 位作者 刘学峰 李淳 王传伟 林海波 张景华 潘淑英 邓立文 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第3期165-168,209,共4页
Through the methods of correlation analysis and main factor analysis, the relationship between the poplar INA bacte-rial canker and circumstances was analyzed and 9 main factors for affecting the disease were selected... Through the methods of correlation analysis and main factor analysis, the relationship between the poplar INA bacte-rial canker and circumstances was analyzed and 9 main factors for affecting the disease were selected. Based on the compre-hensive analysis of main factors and induced factors, the standard for risk grades of this disease was promoted and northeast region of China was divided into 4 districts with different risk grades: seriously occurring district, commonly occurring district, occasionally occurring district, and un-occurring district. Nonlinear regression analysis for six model curves showed that the Richard growth model was suitable for describing the temporal dynamics of poplar INA bacterial canker. By stepwise variable selection method, the multi-variable linear regression forecasting equation was set up to predict the next year抯 disease index, and the GM (1,1) model was also set up by grey method to submit middle or long period forecast. 展开更多
关键词 POPLAR Ice nucleation active (INA) bacterial canker Epidemic law FORECAST
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Classification and Development Laws of Karst Landform in Suzhou Area, North Anhui Province of China
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作者 马艳平 陈松 《Journal of Landscape Research》 2011年第9期92-95,共4页
Suzhou area in north Anhui Province is a low hilly area on the Huaibei Plain where carbonate rocks and karstification are widely distributed, and karst landscapes form major physical contours of the bedrock outcrops. ... Suzhou area in north Anhui Province is a low hilly area on the Huaibei Plain where carbonate rocks and karstification are widely distributed, and karst landscapes form major physical contours of the bedrock outcrops. Through field investigation, karst landscapes of Suzhou area were divided into two categories based on their morphological characteristics: macro-geomorphologic landscapes including normal hills, dry valleys, karst springs and caves, and micro-corrosion landscapes including corrosion pits, dissolved pores, dissolution traces, corrosion cracks, clints and karrens. Distribution, development and scale of karst landscapes in this region are controlled by climate, rock type, structure, topography and other factors. It was suggested that karst landscapes in the study area could be used as a representative of karst landforms in North China. 展开更多
关键词 KARST LANDFORM CLASSIFICATION Development laws KARST in NORTH China Northern Anhui Province
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基于Laws模板滤波的车标定位算法 被引量:4
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作者 杨文文 杨国为 +1 位作者 张鲁波 郑旭 《青岛大学学报(工程技术版)》 CAS 2012年第3期46-50,共5页
针对车标受天气变化的影响而导致无法准确定位的问题,本文提出了基于Laws模板滤波的车标定位方法,根据车牌与车标的先验知识进行车标粗定位,再根据车标周围散热网的纹理信息,并利用Laws模板滤波除去车标周围散热网的干扰,实现车标的精... 针对车标受天气变化的影响而导致无法准确定位的问题,本文提出了基于Laws模板滤波的车标定位方法,根据车牌与车标的先验知识进行车标粗定位,再根据车标周围散热网的纹理信息,并利用Laws模板滤波除去车标周围散热网的干扰,实现车标的精确定位。试验结果表明,本文方法与Sobel边缘检测方法相比,可更好的保留车标纹理信息。该方法提高了车标定位的光照鲁棒性,定位结果更准确,而且对于较暗的车标也有很好的定位效果。 展开更多
关键词 laws模版 纹理分析 形态学 车标定位
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Influences of Cultural Differences on Translation of Titles of Laws
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作者 顾秀梅 《海外英语》 2014年第12X期4-5,共2页
For whatever kind of literary forms, the first thing that we come into contact with is the title. The title functions as not only the eye catcher but also the summary of the context. Any legal document starts with its... For whatever kind of literary forms, the first thing that we come into contact with is the title. The title functions as not only the eye catcher but also the summary of the context. Any legal document starts with its title and a good translation of the title lays the foundation for the interpretation of follow- up terms and conditions. However, translating titles of laws is affected by different factors, especially cultural differences, such as history, diction and conventions. Anyway, cultural impact on translation of law titles can be handled tactfully. 展开更多
关键词 CULTURAL DIFFERENCES TRANSLATION titles of laws
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基于Laws模板与CSLBP的人脸识别
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作者 徐楠楠 李岚 师飞龙 《信息通信》 2014年第5期11-13,共3页
针对CSLBP对人脸图像的局部特征提取不充分问题,提出一种基于Laws模板的CSLBP算法。该算法首先选取Laws模板对原始图像进行滤波,获得多幅纹理单一图像。其次,引进CSLBP算子对各纹理图像进行特征提取,再将图像分成若干子区域,通过连接这... 针对CSLBP对人脸图像的局部特征提取不充分问题,提出一种基于Laws模板的CSLBP算法。该算法首先选取Laws模板对原始图像进行滤波,获得多幅纹理单一图像。其次,引进CSLBP算子对各纹理图像进行特征提取,再将图像分成若干子区域,通过连接这些子区域的CSLBP直方图生成人脸特征向量。最后,针对Laws-CSLBP中存在的高维向量问题,做了进一步研究分析,引入了局部保持投影(LPP)的流行算法进行降维,并采用最近邻分类器进行判别分类。该算法在ORL、FERET人脸库中都取得了较好的识别效果,证明了该算法的有效性。 展开更多
关键词 人脸识别 laws模板 局部中心对称二值模型 局部保持投影
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Residual symmetry, interaction solutions, and conservation laws of the(2+1)-dimensional dispersive long-wave system 被引量:9
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作者 夏亚荣 辛祥鹏 张顺利 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第3期207-214,共8页
We explore the (2+l)-dimensional dispersive long-wave (DLW) system. From the standard truncated Painleve expansion, the Baicklund transformation (BT) and residual symmetries of this system are derived. The intr... We explore the (2+l)-dimensional dispersive long-wave (DLW) system. From the standard truncated Painleve expansion, the Baicklund transformation (BT) and residual symmetries of this system are derived. The introduction to an appropriate auxiliary dependent variable successfully localizes the residual symmetries to Lie point symmetries. In particular, it is verified that the (2+l)-dimensional DLW system is consistent Riccati expansion (CRE) solvable. If the special form of (CRE)-consistent tanh-function expansion (CTE) is taken, the soliton-cnoidal wave solutions and corresponding images can be explicitly given. Furthermore, the conservation laws of the DLW system are investigated with symmetries and Ibragimov theorem. 展开更多
关键词 residual symmetry truncated Painleve expansion interaction solutions conservation law
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RENEWAL OF BASIC LAWS AND PRINCIPLES FOR POLAR CONTINUUM THEORIES (X) -MASTER BALANCE LAW 被引量:3
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作者 戴天民 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第2期167-174,共8页
Through a comparison between the expressions of master balance laws and the conservation laws derived by Noether's theorem, a unified master balance law and six physically possible balance equations for micropolar co... Through a comparison between the expressions of master balance laws and the conservation laws derived by Noether's theorem, a unified master balance law and six physically possible balance equations for micropolar continuum mechanics are naturally deduced. Among them, by extending the well-known conventional concept of energymomentum tensor, the rather general conservation laws and balance equations named after energy-momentum, energy-angular momentum and energy-energy are obtained. It is clear that the forms of the physical field quantities in the master balance law for the last three cases could not be assumed directly by perceiving through the intuition. Finally, some existing results are reduced immediately as special cases. 展开更多
关键词 unified master balance law physical field quantities conservation laws ENERGY-MOMENTUM energy-angular momentum energy-energy
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Conservation laws of the generalized nonlocal nonlinear Schrodinger equation 被引量:5
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作者 欧阳世根 郭旗 +1 位作者 吴立军 兰胜 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第8期2331-2337,共7页
The derivations of several conservation laws of the generalized nonlocal nonlinear Schrodinger equation are presented. These invaxiants are the number of particles, the momentum, the angular momentum and the Hamiltoni... The derivations of several conservation laws of the generalized nonlocal nonlinear Schrodinger equation are presented. These invaxiants are the number of particles, the momentum, the angular momentum and the Hamiltonian in the quantum mechanical analogy. The Lagrangian is also presented. 展开更多
关键词 nonlocal nonlinear Schrodinger equation conservation law LAGRANGIAN
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