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APPLICATION OF ONE-PARAMETER GROUPS OF TRANSFORMATION IN MECHANICS
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作者 许学谘 陈怀永 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第7期679-686,共8页
In this paper,including some partial differential equations with a number of independent variables, which can he reduced by the infinitesimal form of the group, we obtain the theory of similarity transformation and it... In this paper,including some partial differential equations with a number of independent variables, which can he reduced by the infinitesimal form of the group, we obtain the theory of similarity transformation and its application of the second order nonlinear partial differential equations which have two independent variables and two dependent variables in mechanics. 展开更多
关键词 APPLICATION OF one-parameter groupS OF transformation IN MECHANICS
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Digital Construction Paths for Business and Trade Professional Groups in Vocational Colleges under the Background of Industrial Transformation and Upgrading
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作者 Junfeng Di 《Journal of Contemporary Educational Research》 2025年第4期16-22,共7页
In the context of globalization and rapid development of information technology,the transformation of industrial structure has become a major force driving China’s economic and social development.Under this situation... In the context of globalization and rapid development of information technology,the transformation of industrial structure has become a major force driving China’s economic and social development.Under this situation,as an important component of China’s higher vocational education,the information construction of the business and trade professional group is of great significance.The construction of informatization can not only improve the education quality of the business and trade professional group,but also closely connect with the needs of the industry,providing strong talent support for the transformation and upgrading of the industry.Aiming at the problems existing in China’s current economic and social development,this paper proposes a new economic and trade professional system based on information technology,and puts forward corresponding solutions. 展开更多
关键词 Industrial transformation Vocational colleges Business and trade professional group Digital construction
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Lie symmetry group transformation for MHD natural convection flow of nanofluid over linearly porous stretching sheet in presence of thermal stratification 被引量:2
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作者 A.B.ROSMILA R.KANDASAMY I.MUHAIMIN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第5期593-604,共12页
The magnetohydrodynamics (MHD) convection flow and heat transfer of an incompressible viscous nanofluid past a semi-infinite vertical stretching sheet in the pres- ence of thermal stratification are examined. The pa... The magnetohydrodynamics (MHD) convection flow and heat transfer of an incompressible viscous nanofluid past a semi-infinite vertical stretching sheet in the pres- ence of thermal stratification are examined. The partial differential equations governing the problem under consideration are transformed by a special form of the Lie symmetry group transformations, i.e., a one-parameter group of transformations into a system of ordinary differential equations which are numerically solved using the Runge-Kutta-Gill- based shooting method. It is concluded that the flow field, temperature, and nanoparticle volume fraction profiles are significantly influenced by the thermal stratification and the magnetic field. 展开更多
关键词 Lie symmetry group transformation NANOFLUID porous medium thermalstratification magnetic field
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Lie point symmetry algebras and finite transformation groups of the general Broer-Kaup system 被引量:1
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作者 贾曼 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第6期1534-1544,共11页
Using a new symmetry group theory, the transformation groups and symmetries of the general Broer-Kaup system are obtained. The results are much simpler than those obtained via the standard approaches.
关键词 Lie point symmetry finite transformation group new symmetry group theory
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ALMOST PERIODICITY AND EQUICONTINUITY OF THE TOPOLOGICAL TRANSFORMATION GROUP 被引量:1
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作者 Li Zhicong Li Juntao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第4期467-472,共6页
In this paper, a characterization of almost periodicity of topological transformation groups on uniform spaces is given. By searching the appropriate base for uniform structure, it is shown that the topological transf... In this paper, a characterization of almost periodicity of topological transformation groups on uniform spaces is given. By searching the appropriate base for uniform structure, it is shown that the topological transformation group is topologically equivalent to an isometric one if it is uniformly equicontinuous. 展开更多
关键词 uniform space topological transformation group EQUICONTINUITY almost periodicity compactly almost periodicity.
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基于GRU-Transformer与随机矩阵的机动群目标跟踪
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作者 陈烨 梁苑 +1 位作者 李银伢 戚国庆 《兵工学报》 北大核心 2026年第1期282-295,共14页
针对机动群目标跟踪问题,提出基于多任务多头门控循环单元变换器(Gated Recurrent Unit Transformer,GRU-Transformer)的机动模型辨识与当前统计(Current Statistical,CS)模型机动频率参数α回归,并将判别结果融入随机矩阵椭球-贝叶斯更... 针对机动群目标跟踪问题,提出基于多任务多头门控循环单元变换器(Gated Recurrent Unit Transformer,GRU-Transformer)的机动模型辨识与当前统计(Current Statistical,CS)模型机动频率参数α回归,并将判别结果融入随机矩阵椭球-贝叶斯更新,实现群目标质心与扩展外形的联合跟踪。基于机动群目标时间序列量测数据,提取群目标运动多项特征参数,输入所提深度神经网络,实现机动群目标运动模型(匀速(Constant Velocity,CV)模型、匀加速(Constant Acceleration,CA)模型、CS模型)的精准辨别,若目标模型为CS运动模型,同时输出机动频率参数α的精确估计结果。运用随机矩阵群目标跟踪理论,提出一种基于贝叶斯状态估计架构的椭圆机动群目标跟踪方法。仿真实验结果分析表明:新方法可实现对机动椭圆群目标的精确稳健跟踪,相较于传统交互式多模型群目标跟踪方法,跟踪精度有显著提升。 展开更多
关键词 机动群目标跟踪 注意力GRU-transformer深度神经网络 群目标跟踪 运动模型辨识 机动频率参数估计
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A GROUP REPRESENTATION OF CANONICAL TRANSFORMATION
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作者 侯碧辉 杨洪波 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第4期345-350,共6页
The mutual relationships between four generating functions F-1(q, Q), F-2(q, P), F-3(p, P), F-4(p, Q) and four kinds of canonical variables q, p, Q, P concerned in Hamilton's canonical transformations, can be got ... The mutual relationships between four generating functions F-1(q, Q), F-2(q, P), F-3(p, P), F-4(p, Q) and four kinds of canonical variables q, p, Q, P concerned in Hamilton's canonical transformations, can be got with linear transformations from seven basic formulae. All of them are Legendre's transformation, which are implemented by 32 matrices of 8 x 8 which are homomorphic to D-4 point group of 8 elements with correspondence of 4:1. Transformations and relationships of four state functions G(P, T), H(P, S), U(V, S), F(V, T) and four variables P, V, T, S in thermodynamics, are just the same Lagendre's transformations with the relationships of canonical transformations. The state functions of thermodynamics are summarily founded on experimental results of macroscope measurements, and Hamilton's canonical transformations are theoretical generalization of classical mechanics. Both group represents are the same, and it is to say, their mathematical frames are the same. This generality indicates the thermodynamical transformation is an example of one-dimensional Hamilton's canonical transformation. 展开更多
关键词 canonical transformations group theory group represent transformation matrix
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Improved Gabor transform and group sparse representation for ancient mural inpainting
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作者 ZHAO Mengxue CHEN Yong TAO Meifeng 《Journal of Measurement Science and Instrumentation》 2025年第3期384-394,共11页
Sparse representation has been highly successful in various tasks related to image processing and computer vision.For ancient mural image inpainting,traditional group sparse representation models usually lead to struc... Sparse representation has been highly successful in various tasks related to image processing and computer vision.For ancient mural image inpainting,traditional group sparse representation models usually lead to structure blur and line discontinuity due to the construction of similarity group solely based on the Euclidean distance and the randomness of dictionary initialization.To address the aforementioned issues,an improved curvature Gabor transform and group sparse representation(CGabor-GSR)model for ancient Dunhuang mural inpainting is proposed.To begin with,mutual information is introduced to weight the Euclidean distance,and then the weighted Euclidean distance acts as a new standard of similarity group.Subsequently,to mitigate the randomness of dictionary initialization,a curvature Gabor wavelet transform is proposed to extract the features and initialize the feature dictionary with dimension reduction based on principal component analysis(PCA).Ultimately,singular value decomposition(SVD)and split Bregman iteration(SBI)can be used to resolve the CGabor-GSR model to reconstruct the mural images.Experimental results on Dunhuang mural inpainting demonstrate tha the proposed CGabor-GSR achieves a better performance than compared algorithms in both objective and visual evaluation. 展开更多
关键词 digital image processing mural inpainting curvature Gabor wavelet transform group sparse representation mutual information
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Profound Transformations on the Snowy Plateau
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作者 Wang Junzheng 《Foreign Affairs Journal》 2025年第3期7-21,93-98,共21页
In September 1965,the Xizang Autonomous Region was officially founded.A new page was turned in Xizang's history,one that saw people of all ethnic groups in Xizang forge ahead together in pursuit of shared progress... In September 1965,the Xizang Autonomous Region was officially founded.A new page was turned in Xizang's history,one that saw people of all ethnic groups in Xizang forge ahead together in pursuit of shared progress and prosperity.Over the past 60 years,under the leadership of the Communist Party of China(CPC)and with the strong support of the entire country. 展开更多
关键词 shared progress ethnic groups LEADERSHIP xizang autonomous region Communist Party China PROSPERITY foundational page profound transformations
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CISCE and Yili:The Transformation of Chinese Diary Industry from Chasing to Surpassing in Production Chain
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作者 Lan Xin 《China's Foreign Trade》 2025年第3期54-59,共6页
As the first national exhibition with the theme of supply chain,China International Supply Chain Expo(hereinafter referred to as the CISCE)has already become a key spot to observe the establishment of the Chinese ente... As the first national exhibition with the theme of supply chain,China International Supply Chain Expo(hereinafter referred to as the CISCE)has already become a key spot to observe the establishment of the Chinese enterprise industry chain.During the evolution of three CISCE,the leading dairy enterprise,Yili Group(hereinafter referred to as Yili),takes the practice of the entire industry chain as a sample,clearly outlining the development trajectory of China's dairy industry from“following”to“leading”.Its explorations of indust r ial chain col laborat ion,green transformation,and global layout are prominent.Therefore,providing a good paradigm for the high-quality development of the real economy. 展开更多
关键词 supply chain supply chainchina Chinese dairy industry global layout green transformation Yili group industrial chain collaboration
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Re-deriving data consistency condition in radon domain from perspective of Lie transformation group 被引量:1
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作者 TANG Shaojie TONG Kuan +8 位作者 DUAN Jiayu LI Yang XU Qiong WU Junfeng QIAO Zhiwei CHEN Cheng CONG Zhoujian WANG Linghang MOU Xuanqin 《中国体视学与图像分析》 2024年第4期311-319,共9页
In this paper,a data consistency condition(DCC)in Radon domain is re-derived from the perspective of Lie transformation group and compared with other two derivations.By carefully observing the proof procedure on the b... In this paper,a data consistency condition(DCC)in Radon domain is re-derived from the perspective of Lie transformation group and compared with other two derivations.By carefully observing the proof procedure on the basis of Lie transformation group,we may have a deeper insight on the essence of this DCC.Moreover,it may help determine whether there are the corresponding counterparts in both image and Radon domains.Following this line of thought,more data consistency conditions will possibly be explored in the future.This is definitely critical as data consistency conditions would be applied to the construction of algorithms for next-generation CT imaging. 展开更多
关键词 computed tomography consistency condition radon transform Lie transformation group
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Finite symmetry transformation group and localized structures of the (2+1)-dimensional coupled Burgers equation
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作者 雷娅 杨铎 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期46-49,共4页
In this paper, the finite symmetry transformation group of the (2+1)-dimensional coupled Burgers equation is studied by the modified direct method, and with the help of the truncated Painleve′ expansion approach, ... In this paper, the finite symmetry transformation group of the (2+1)-dimensional coupled Burgers equation is studied by the modified direct method, and with the help of the truncated Painleve′ expansion approach, some special localized structures for the (2+1)-dimensional coupled Burgers equation are obtained, in particular, the dromion-like and solitoff-like structures. 展开更多
关键词 finite transformation group modified direct method truncated Painleve′ expansion approach localized structure
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On the Group of Units for the Ring of Linear Transformations
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作者 张光辉 孙应德 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第4期355-359,共5页
In this paper, we introduce a practical method for obtaining the structure of thegroup of units for the ring of linear transformations of a vector space over an arbitrary field,and we give a further generalization of ... In this paper, we introduce a practical method for obtaining the structure of thegroup of units for the ring of linear transformations of a vector space over an arbitrary field,and we give a further generalization of the result in [3]. 展开更多
关键词 semidirect product linear transformation normal group BASIS
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样本生成与Swin Transformer-YOLO网络结合的声呐图像目标检测
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作者 罗雨薇 霍冠英 成振 《声学学报》 北大核心 2026年第1期201-215,共15页
由于目标投放成本高和实验条件限制,声呐图像样本稀缺且质量较差,导致现有目标检测方法难以有效学习特征,限制了性能提升。为解决这一问题,本文提出了一种基于扩散模型样本生成与Swin Transformer-级联群体注意力机制(CGA)融合的改进YOL... 由于目标投放成本高和实验条件限制,声呐图像样本稀缺且质量较差,导致现有目标检测方法难以有效学习特征,限制了性能提升。为解决这一问题,本文提出了一种基于扩散模型样本生成与Swin Transformer-级联群体注意力机制(CGA)融合的改进YOLO模型(STC-YOLO)的声呐图像目标检测方法。首先,利用LoRA对稳定扩散模型进行参数调整,并结合BLIP文本模型的语义特征,生成高质量、多样化的声呐图像,以构建新的数据集。其次,将Swin Transformer结构引入YOLOv8的主干网络,增强小目标的多尺度特征提取能力,同时在C2f模块中融合CGA机制,以增强小目标的感知能力。最后,采用偏斜交并比损失函数(SIoU)以适应复杂的水下场景。实验结果表明,所训练的生成模型能够在数据有限的情况下生成多样且真实的新样本。与原YOLOv8模型相比,改进后的STC-YOLO模型检测精度提升了5%,平均精度提升了12.6%,实现了对水下小目标的高精度检测。 展开更多
关键词 声呐图像 小目标检测 稳定扩散模型 Swin transformer 级联群体注意力机制
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融合KAN与Transformer的分心驾驶行为增强检测模型
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作者 陈万志 于南洋 范兴杰 《安全与环境学报》 北大核心 2026年第1期88-99,共12页
分心驾驶行为的精准检测对于驾驶安全预警至关重要。为解决复杂驾驶场景中现有安全监测模型易受噪声干扰、细粒度行为识别不足及实时性差等问题,提出一种融合Kolmogorov-Arnold网络与Transformer的增强检测模型。首先,重构分组共享的Kol... 分心驾驶行为的精准检测对于驾驶安全预警至关重要。为解决复杂驾驶场景中现有安全监测模型易受噪声干扰、细粒度行为识别不足及实时性差等问题,提出一种融合Kolmogorov-Arnold网络与Transformer的增强检测模型。首先,重构分组共享的Kolmogorov-Arnold网络,通过有理函数逼近与分组参数共享减少参数量,增强微动作特征的提取;其次,采用多尺度扩张注意力机制,通过滑动窗口稀疏采样与渐进扩张率分配,实现局部细节感知与长程上下文建模的协同优化;最后,通过训练优化模型实现分心驾驶行为的分类检测。试验结果表明,所提模型在典型数据集上检测精度达92.3%(较基线提升8.5百分点),实时速度为45帧/s,遮挡召回率提升11.7百分点。所提模型在平衡检测精度的同时实现了轻量化设计,满足智能驾驶安全预警中分心驾驶行为的实时检测需求。 展开更多
关键词 安全工程 驾驶安全 Kolmogorov-Arnold网络 transformer模型 分组共享 多尺度扩张注意力
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A Cross-Cultural Study on Transformational Leadership
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作者 许薇 《海外英语》 2016年第13期136-137,共2页
This paper examines transformational leadership theory and the relationship between transformational leadership and group performance as well. Transformational leadership asks leaders to understand the needs of follow... This paper examines transformational leadership theory and the relationship between transformational leadership and group performance as well. Transformational leadership asks leaders to understand the needs of followers and motivate followers for their overall development, which brings benefits to a group. It is hoped that this paper can contribute to comparative studies on Transformational leadership in the U.S. and China. 展开更多
关键词 LEADERSHIP hoped LEADERSHIP encourage LIKELY BENEFITS validity SITUATIONS originally MOTIVATION
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THE UNIFORMLY BOUNDEDNESS OF THE RIESZ TRANSFORMS ON THE CAYLEY HEISENBERG GROUPS 被引量:2
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作者 栾静闻 朱赋鎏 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期895-914,共20页
In this article,the authors estimate some functions by using the explicit expression of the heat kernels for the Cayley Heisenberg groups,and then prove the uniform boundedness of the Riesz transforms on these nilpote... In this article,the authors estimate some functions by using the explicit expression of the heat kernels for the Cayley Heisenberg groups,and then prove the uniform boundedness of the Riesz transforms on these nilpotent Lie groups. 展开更多
关键词 Cayley Heisenberg group heat kernel Riesz transform
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Noether Symmetry Can Lead to Non-Noether Conserved Quantity of Holonomic Nonconservative Systems in General Lie Transformations 被引量:4
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作者 LUOShao-Kai JIALi-Qun CAIJian-Le 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期193-196,共4页
For the holonomic nonconservative system, by using the Noether symmetry, a non-Noether conserved quantity is obtained directly under general infinitesimal transformations of groups in which time is variable. At first,... For the holonomic nonconservative system, by using the Noether symmetry, a non-Noether conserved quantity is obtained directly under general infinitesimal transformations of groups in which time is variable. At first,the Noether symmetry, Lie symmetry, and Noether conserved quantity are given. Secondly, the condition under which the Noether symmetry is a Lie symmetry under general infinitesimal transformations is obtained. Finally, a set of nonNoether conserved quantities of the system are given by the Noether symmetry, and an example is given to illustrate the application of the results. 展开更多
关键词 holonomic conservative system noether symmetry non-Noether conservedquantity general inifinitesimal transformations of groups
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A Note on <i>m</i>-Möbius Transformations 被引量:2
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作者 Dorin Ghisa 《Advances in Pure Mathematics》 2021年第11期883-890,共8页
Lie groups of bi-M<span style="white-space:nowrap;">&#246;bius transformations are known and their actions on non orientable n-dimensional complex manifolds have been studied. In this paper, m-M<... Lie groups of bi-M<span style="white-space:nowrap;">&#246;bius transformations are known and their actions on non orientable n-dimensional complex manifolds have been studied. In this paper, m-M<span style="white-space:nowrap;">&#246;bius transformations are introduced and similar problems as those related to bi-M<span style="white-space:nowrap;">&#246;bius transformations are tackled. In particular, it is shown that the subgroup generated by every m-M<span style="white-space:nowrap;">&#246;bius transformation is a discrete group. Cyclic subgroups are exhibited. Vector valued m-M<span style="white-space:nowrap;">&#246;bius transformations are also studied. 展开更多
关键词 Möbius transformation Complex Manifold Lie group
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Hardy Type Estimates for Riesz Transforms Associated with Schrdinger Operators on the Heisenberg Group
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作者 Yu Liu Guobin Tang 《Analysis in Theory and Applications》 CSCD 2016年第1期78-89,共12页
Abstract. Let H^n be the Heisenberg group and Q = 2n+2 be its homogeneous dimen- sion. In this paper, we consider the Schr6dinger operator -△H^n +V, where △H^n is the sub-Laplacian and V is the nonnegative potenti... Abstract. Let H^n be the Heisenberg group and Q = 2n+2 be its homogeneous dimen- sion. In this paper, we consider the Schr6dinger operator -△H^n +V, where △H^n is the sub-Laplacian and V is the nonnegative potential belonging to the reverse H61der class Bql for ql _〉 Q/2. We show that the operators T1 = V(-△H^n-In +V)-1 and T2 = V1/2(-△H^n-V)-1/2 are both bounded from 1 n HL^1(H^n ) into L1(H^n). Our results are also valid on the stratified Lie group. 展开更多
关键词 Heisenberg group stratified Lie group reverse H61der class Riesz transform Schr6dinger operator.
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