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SELF-DEPENDENT LOCALITY PRESERVING PROJECTION WITH TRANSFORMED SPACE-ORIENTED NEIGHBORHOOD GRAPH
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作者 乔立山 张丽梅 孙忠贵 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第3期261-268,共8页
Locality preserving projection (LPP) is a typical and popular dimensionality reduction (DR) method,and it can potentially find discriminative projection directions by preserving the local geometric structure in da... Locality preserving projection (LPP) is a typical and popular dimensionality reduction (DR) method,and it can potentially find discriminative projection directions by preserving the local geometric structure in data. However,LPP is based on the neighborhood graph artificially constructed from the original data,and the performance of LPP relies on how well the nearest neighbor criterion work in the original space. To address this issue,a novel DR algorithm,called the self-dependent LPP (sdLPP) is proposed. And it is based on the fact that the nearest neighbor criterion usually achieves better performance in LPP transformed space than that in the original space. Firstly,LPP is performed based on the typical neighborhood graph; then,a new neighborhood graph is constructed in LPP transformed space and repeats LPP. Furthermore,a new criterion,called the improved Laplacian score,is developed as an empirical reference for the discriminative power and the iterative termination. Finally,the feasibility and the effectiveness of the method are verified by several publicly available UCI and face data sets with promising results. 展开更多
关键词 graphic methods Laplacian transforms unsupervised learning dimensionality reduction locality preserving projection
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Coherent State Projection Operator Representation of Symplectic Transformations as a Loyal Representation of Symplectic Group
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作者 FAN Hong-Yi CHEN Jun-Hua 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第8期147-150,共4页
We find that the coherent state projection operator representation of symplectic transformation constitutesa loyal group representation of symplectic group. The result of successively applying squeezing operators on n... We find that the coherent state projection operator representation of symplectic transformation constitutesa loyal group representation of symplectic group. The result of successively applying squeezing operators on numberstate can be easily derived. 展开更多
关键词 COHERENT state projection operator SYMPLECTIC transformation SQUEEZING OPERATOR
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Focus projection of the parabolic radon transform and multiple waves separator, elimination
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作者 张建贵 宋守根 袁修贵 《Journal of Central South University of Technology》 2002年第1期30-35,共6页
Based on the scalar wave equation, making use of the ray approximation of the reflected seismic data (CMP or CSP gathers), the authors derive respectively the projection function of the primary waves and multiple wave... Based on the scalar wave equation, making use of the ray approximation of the reflected seismic data (CMP or CSP gathers), the authors derive respectively the projection function of the primary waves and multiple waves at the near offset (CMP or CSP gathers) in the parabolic Radon transform(PRT)domain. From the geometric point, the authors prove that the energy of the reflection still distributes along hyperbola which has higher curvature in the PRT domain and becomes some energy masses. So the primary waves and the multiple waves which interweave each other in ( x, t ) domain can be completely separated, which helps the multiple waves eliminated by filtering or muting. It is important for the analysis of velocity and the separator and elimination of multiple waves. 展开更多
关键词 parabolic Radon transform multiple waves projection FOCUS
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Research and Implementation for License Plate Recognition Based on Improved Projection Algorithm 被引量:1
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作者 LI Xiu-juan Yimamu' aishan.Abudoulikemu 《Computer Aided Drafting,Design and Manufacturing》 2013年第2期53-56,75,共5页
This paper analyzes and dissertates the discrete wavelet transform and improved projection algorithm in four kernel stages (image preprocessing, license plate localization, character segmentation, license plate recog... This paper analyzes and dissertates the discrete wavelet transform and improved projection algorithm in four kernel stages (image preprocessing, license plate localization, character segmentation, license plate recognition, i.e.) of license plate recognition system in detail. At last, it gives some conclusions and suggestions on future research. 展开更多
关键词 license plate recognition wavelet transform improved projection algorithm
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Research Progress of On-line Monitoring Technology for Electromagnetic Environment of Power Transmission and Transformation Projects
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作者 Li Peiming Zhou Jian +2 位作者 Xiao Jun Wang Wenjin Ge Xiaoyang 《Meteorological and Environmental Research》 CAS 2019年第6期67-71,共5页
Based on the collection of relevant literature and cases,the research and application status of on-line monitoring technology for electromagnetic environment of power transmission and transformation projects at home a... Based on the collection of relevant literature and cases,the research and application status of on-line monitoring technology for electromagnetic environment of power transmission and transformation projects at home and abroad were introduced.Moreover,the problems existing in the on-line monitoring of electromagnetic environment were expounded,and the development prospect was forecasted. 展开更多
关键词 ON-LINE monitoring TECHNOLOGY ELECTROMAGNETIC environment Power TRANSMISSION and transformATION project
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Quality Guided Phase Unwrapping for Fringe Projection Profilometry 被引量:1
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作者 C.J.Tay 《实验力学》 CSCD 北大核心 2006年第1期71-76,共6页
Fringe projection technique is a non-contact, full field 3-D shape measurement method. The object depth information is recorded in one or several deformed fringe patterns. The phase-shifting algorithm or the Fourier t... Fringe projection technique is a non-contact, full field 3-D shape measurement method. The object depth information is recorded in one or several deformed fringe patterns. The phase-shifting algorithm or the Fourier transform method can be used to extract the wrapped phase data. A phase unwrapping process is then applied to retrieve a continuous phase distribution, which represents the surface profile of the test object. In this paper, a quality-guided phase unwrapping approach is incorporated and two novel phase quality evaluation methods are proposed to facilitate the phase unwrapping process. 展开更多
关键词 相品质 相展开 边缘发射 相移 傅立叶变换
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On the Analog of Shephard Problem for L_p-polar Projection Bodies
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作者 马统一 《Chinese Quarterly Journal of Mathematics》 2015年第4期596-609,共14页
For p > 0, Lutwak, Yang and Zhang introduced the concept of L_p-polar projection body Γ_(-p)K of a convex body K in Rn. Let p ≥ 1 and K, L ? Rnbe two origin-symmetric convex bodies, we consider the question of wh... For p > 0, Lutwak, Yang and Zhang introduced the concept of L_p-polar projection body Γ_(-p)K of a convex body K in Rn. Let p ≥ 1 and K, L ? Rnbe two origin-symmetric convex bodies, we consider the question of whether Γ_(-p) K ? Γ_(-p) L implies ?_p(L) ≤ ?_p(K),where ?_p(K) denotes the L_p-affine surface area of K and K = Voln(K)^(-1/p) K. We prove a necessary and sufficient condition of an analog of the Shephard problem for the L_p-polar projection bodies. 展开更多
关键词 convex body Lp-polar projection body Lp-affine surface area Fourier transform Shephard problem
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Application of 3D Projection Profilometry in the High Speed Impaction Surface Deformation Measurement Research
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作者 Eryi Hu 《Journal of Signal and Information Processing》 2020年第4期103-115,共13页
In order to study the strength of the composite material plate problems, need to adopt a nondestructive testing method to obtain the specimen surface under the effect of high-speed impact regularity of shape. The proj... In order to study the strength of the composite material plate problems, need to adopt a nondestructive testing method to obtain the specimen surface under the effect of high-speed impact regularity of shape. The projection profilometry was used to measure the surface profile or the full field deformation. Furtherly, by using the Fourier transform algorithm, there is only one frame of captured image</span><span style="font-family:Verdana;"> which</span><span style="font-family:Verdana;"> is needed in the measurement, so that it can be introduced into the high speed impaction procedure measurement. An experimental system, which was contained with an impact setup and the projection profilometry measurement part, was constructed for the impaction action characteristic research. The metallic impact object can be launched by a gas gun or a spin fan, respectively. The detected object </span><span style="font-family:Verdana;">is</span><span style="font-family:Verdana;"> manufactured by composite materials. In order to increase the surface deformation measurement accuracy, the calibration method and the error was discussed with different calibration specimen. And then, the proposed profilometry measurement method is proved by the gas gun and spin fan projectile test. The surface deformation of the manufactured composite plates and fan case are measured in the impaction procedure. So that the impact action details can be described much more clearly than the traditional video monitoring method. 展开更多
关键词 projection Profilometry Fourier transform Algorithm Deformation Measurement Impaction Monitoring
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Verifiable Secret Sharing Scheme Based on Certain Projective Transformation
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作者 Bin Li 《American Journal of Computational Mathematics》 2021年第2期175-188,共14页
The main purpose of verifiable secret sharing scheme is to solve the honesty problem of participants. In this paper, the concept of nonzero <em>k</em>-submatrix and theresidual vector of system of hyperpla... The main purpose of verifiable secret sharing scheme is to solve the honesty problem of participants. In this paper, the concept of nonzero <em>k</em>-submatrix and theresidual vector of system of hyperplane intersecting line equations is proposed. Based on certain projective transformations in projective space, a verifiable (<em>t</em>, <em>n</em>)-threshold secret sharing scheme is designed by using the structure of solutions of linear equations and the difficulty of solving discrete logarithm problems. The results show that this scheme can verify the correctness of the subkey provided by each participant before the reconstruction of the master key, and can effectively identify the fraudster. The fraudster can only cheat by guessing and the probability of success is only 1/<em>p</em>. The design of the scheme is exquisite and the calculation complexity is small. Each participant only needs to hold a subkey, which is convenient for management and use. The analysis shows that the scheme in this paper meets the security requirements and rules of secret sharing, and it is a computationally secure and effective scheme with good practical value. 展开更多
关键词 Threshold Secret Sharing projective transformation Nonzero k–Submatrix Residual Vector of Equations
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Tender for 500 kV transformers and switchgears forThree Gorges Project is ready
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《Electricity》 1998年第2期46-46,共1页
关键词 project Tender for 500 kV transformers and switchgears for KV
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Filter back-projection technique applied to Abel inversion
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作者 JiangShano-En LiuZhong-Li 《Nuclear Science and Techniques》 SCIE CAS CSCD 1997年第4期214-217,共4页
FilterbackprojectiontechniqueappliedtoAbelinversionTheProjectSupportedbyNationalHighTechnology836Plan416Spec... FilterbackprojectiontechniqueappliedtoAbelinversionTheProjectSupportedbyNationalHighTechnology836Plan416SpecialSubjectandS... 展开更多
关键词 等离体 物理参数 阿贝尔反演 滤波功能
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ABB Chongqing Co. Ltd Will Provide 500 kV Transformers for Three Gorges Hydropower Station Project
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《Electricity》 2000年第2期58-58,共1页
关键词 Ltd Will Provide 500 kV transformers for Three Gorges Hydropower Station project ABB Chongqing Co KV
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Study on Management System for Agricultural Sci-tech Achievement Transformation Funding Project
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作者 ZHANG Hong YU Jun 《Asian Agricultural Research》 2013年第1期55-58,共4页
Relying on the management system for agricultural sci-tech achievement transformation funding project in Zhejiang Province, on the basis of current situations and demand of agricultural sci-tech achievement transforma... Relying on the management system for agricultural sci-tech achievement transformation funding project in Zhejiang Province, on the basis of current situations and demand of agricultural sci-tech achievement transformation funding project management system, we present a B/S-structured and J2EE platform-based system which adopts MVC mode and integrates mainstream open-source frame technologies such as Spring, Struts2, ExtJs, TopLink and FreeMarker, etc. Practice has shown that this system provides an original model for management of sci-tech project application, and various projects can be expanded on this model. With the aid of this system, sci-tech project management personnel can be relieved from trivial manual works, so as to increase working efficiency and improve management level of sci-tech project management. 展开更多
关键词 transformATION of AGRICULTURAL SCI-TECH achievemen
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基于Vision Transformer和卷积注入的车辆重识别
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作者 于洋 马浩伟 +2 位作者 岑世欣 李扬 张梦泉 《河北工业大学学报》 CAS 2024年第4期40-50,共11页
针对车辆重识别中提取特征鲁棒性不高的问题,本文提出基于Vision Transformer的车辆重识别方法。首先,利用注意力机制提出目标导向映射模块,并结合辅助信息嵌入模块,抑制由不同视角、相机拍摄及无效背景引入的噪声。其次,以Vision Trans... 针对车辆重识别中提取特征鲁棒性不高的问题,本文提出基于Vision Transformer的车辆重识别方法。首先,利用注意力机制提出目标导向映射模块,并结合辅助信息嵌入模块,抑制由不同视角、相机拍摄及无效背景引入的噪声。其次,以Vision Transformer远距离建模能力为基础提出通道感知模块,通过并行设计模型能够同时获取图像块之间和图像通道之间的特征,在关注图像块之间关联的基础上,进一步构建通道之间的关联。最后,利用卷积神经网络的局部归纳偏置,将全局特征向量输入到卷积注入模块中进行细化,并与全局特征联合优化,以构建鲁棒性的车辆特征。为了验证提出方法的有效性,在Ve⁃Ri776、VehicleID和VeRi-Wild数据集上分别进行了实验验证。实验结果证明,本文的方法取得了良好的效果。 展开更多
关键词 车辆重识别 Vision transformer 卷积神经网络 目标导向映射 通道感知
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基于特征间几何约束的指针仪表读数识别方法
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作者 刘昶 卢景峰 刘青 《沈阳理工大学学报》 CAS 2025年第1期1-8,共8页
在指针式仪表示值监控系统中,倾斜拍摄仪表图像时会导致识别结果出现偏差,为此提出一种基于仪表特征间几何约束的识别方法。首先利用一幅平铺于仪表上表面的平面标定板图像实现相机参数标定,生成仪表在标定平面上的虚拟图像;然后利用表... 在指针式仪表示值监控系统中,倾斜拍摄仪表图像时会导致识别结果出现偏差,为此提出一种基于仪表特征间几何约束的识别方法。首先利用一幅平铺于仪表上表面的平面标定板图像实现相机参数标定,生成仪表在标定平面上的虚拟图像;然后利用表壳上表面、刻度平面、指针平面与虚拟像平面间的平行关系,确定表壳圆的圆心、仪表刻度圆心、指针转轴中心特征间的透视投影约束关系,利用图像的极坐标变换和离散傅里叶变换提取仪表刻度圆心的最优位置及起始刻度线的角度,利用Hough变换的投票原理估计指针的转动角度;最后利用角度法实现仪表读数的解算。以某型号指针式温度计为测试对象进行实验验证,识别结果的平均误差为0.23℃,最大误差为0.7℃,本文方法能够准确识别仪表读数且识别精度优于人工读数。 展开更多
关键词 指针式仪表 透视投影约束 相机标定 离散傅里叶变换
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大型设施建设重大装置科技成果的产品化分析
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作者 赵木 李璐 +2 位作者 刘学良 李兵 赵璇 《科技创新与应用》 2025年第1期9-12,共4页
大型设施建设重大装置科技成果需要经历一系列过程实现产品化。该文介绍产品化关键路径及各节点的核心内容,重大装置科技成果转化主要影响因素,产品化阶段科研工作主要任务及型号化大数据库建立的主要内容。大型设施建设重大装置科技成... 大型设施建设重大装置科技成果需要经历一系列过程实现产品化。该文介绍产品化关键路径及各节点的核心内容,重大装置科技成果转化主要影响因素,产品化阶段科研工作主要任务及型号化大数据库建立的主要内容。大型设施建设重大装置科技成果产品化实现经济与社会效益最大化,实现科技创新的最终目的。 展开更多
关键词 重大装置 产品化 成果转化 示范工程 大型设施
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一种旋转不变的目标识别算法
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作者 陈国玺 姜振东 +1 位作者 杨贝贝 张姗姗 《农业装备与车辆工程》 2025年第1期129-133,共5页
为了解决目标图像旋转角度造成的误匹配问题并提高算法的运行速度,提出了一种旋转不变的目标识别算法。该算法融合了圆投影和小波变换的优点,通过圆环面投影方法对图像进行预处理,保证特征的旋转不变性;采用小波变换对目标图像和模板图... 为了解决目标图像旋转角度造成的误匹配问题并提高算法的运行速度,提出了一种旋转不变的目标识别算法。该算法融合了圆投影和小波变换的优点,通过圆环面投影方法对图像进行预处理,保证特征的旋转不变性;采用小波变换对目标图像和模板图像进行降维,加快算法的运行速度;选择基于方差结构相似性算法作为图像特征量进行目标区域识别,提高目标区域的识别精度。将不同背景环境下的图像与传统目标识别算法以及其他旋转不变算法相比较,结果表明,所提算法在目标识别过程中不仅能够解决目标图像的旋转问题,而且能够提高算法的运行速度,识别准确率超过94%,适用于较复杂背景下目标图像的识别。 展开更多
关键词 目标识别 旋转不变 圆环投影 小波变换 基于最小方差的结构相似性算法
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大概念视域下高中化学项目式学习单元教学设计--以“葡萄酒中含硫物质的转化”为例
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作者 孙婷婷 《科教文汇》 2025年第1期168-174,共7页
在大概念统摄下,基于真实情境发现并解决问题是认识元素化合物性质及转化的重要方法,也是落实学科核心素养的重要途径。教师通过抽取大概念,基于情境设计驱动问题,完成对“硫的转化”这一主题单元的规划。将教学内容结构化,开展以学生... 在大概念统摄下,基于真实情境发现并解决问题是认识元素化合物性质及转化的重要方法,也是落实学科核心素养的重要途径。教师通过抽取大概念,基于情境设计驱动问题,完成对“硫的转化”这一主题单元的规划。将教学内容结构化,开展以学生探究为主的小组实验,运用“价—类”二维图模型认识“葡萄酒中含硫物质的转化”,培养学生的创新精神和实践能力。学生在参与讨论“食品安全”“酸雨”等社会性议题过程中,认识到合理利用资源和保护环境的重要性,培养了社会责任感和绿色化学观。 展开更多
关键词 大概念 项目式学习 单元教学 食品添加剂 转化观 绿色化学观
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APPLICATION OF COMPUTER GRAPHICS IN MARTENSITIC TRANSFORMATION 被引量:3
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作者 Zhou JianqiSouthern Naval Unit of Institute of Naval Technical Equipment in Zhanjiang Manuscript received 18 April, 1994 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1994年第2期103-106,共4页
This paper discuss the stereographic method of martensitic transformation (MT)in the view of computer graphics (CG) and programs are programmed to realize this method. Habit plane resulting from the programs agrees wi... This paper discuss the stereographic method of martensitic transformation (MT)in the view of computer graphics (CG) and programs are programmed to realize this method. Habit plane resulting from the programs agrees with that of numerical analysis in terms of the lattice parameters of austenite and martensite and shear mechanism supposed in Fe-22%Ni-0.8%C alloy, so does orientation relationships. 展开更多
关键词 stereograpllic projection martensitic transformation computer graphics
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Dynamic analysis of a new chaotic system with fractional order and its generalized projective synchronization 被引量:1
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作者 牛玉军 王兴元 +1 位作者 年福忠 王明军 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期97-104,共8页
Based on the stability theory of the fractional order system, the dynamic behaviours of a new fractional order system are investigated theoretically. The lowest order we found to have chaos in the new three-dimensiona... Based on the stability theory of the fractional order system, the dynamic behaviours of a new fractional order system are investigated theoretically. The lowest order we found to have chaos in the new three-dimensional system is 2.46, and the period routes to chaos in the new fractional order system are also found. The effectiveness of our analysis results is further verified by numerical simulations and positive largest Lyapunov exponent. Furthermore, a nonlinear feedback controller is designed to achieve the generalized projective synchronization of the fractional order chaotic system, and its validity is proved by Laplace transformation theory. 展开更多
关键词 dynamic analysis fractional order generalized projective synchronization Laplace transformation
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