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基于AutoCAD Projector辅助软件的夹具设计 被引量:1
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作者 陈燕 《煤矿机械》 北大核心 2011年第4期225-226,共2页
借助AutoCAD平台上二次开发后形成的Projector软件进行加工工件及其夹具零件的设计,具有简便易行的特性,克服了在短时间内熟练使用大型设计软件的困难。结合Projector软件设计拨叉工件及其夹具零件,简化了设计过程,为其他设计研究提供... 借助AutoCAD平台上二次开发后形成的Projector软件进行加工工件及其夹具零件的设计,具有简便易行的特性,克服了在短时间内熟练使用大型设计软件的困难。结合Projector软件设计拨叉工件及其夹具零件,简化了设计过程,为其他设计研究提供了新的思路。 展开更多
关键词 AUTOCAD projector 加工零件 夹具设计
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The Null and Column Spaces of Combinations of Two Projectors 被引量:1
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作者 Tao XIE Xiaokun ZHU Kezheng ZUO 《Journal of Mathematical Research with Applications》 CSCD 2016年第4期407-422,共16页
This paper establishes some new equalities and inequalities for the null and column spaces of combinations of two projectors P and Q. Some new necessary and sufficient conditions for P ± Q to be invertible are gi... This paper establishes some new equalities and inequalities for the null and column spaces of combinations of two projectors P and Q. Some new necessary and sufficient conditions for P ± Q to be invertible are given by the structure of null and column space of some combinations of P and Q. In addition, the inclusion relation of Af(PQ + QP) and N(PQ - QP) is discussed and necessary and sufficient conditions for them to be equal are also studied. 展开更多
关键词 projector orthogonal projector null space column space
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The Experimental Research on the Classroom Teaching Mode of Appropriate Combination of Traditional Methods with the Multimedia Overhead Projector
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作者 于秀莲 《Sino-US English Teaching》 2006年第8期1-6,共6页
Based on the constructivism, using the College English(new edition) CD-ROMs for classroom teaching as main media, this paper explores the feasibility of the classroom teaching mode of appropriate combination of trad... Based on the constructivism, using the College English(new edition) CD-ROMs for classroom teaching as main media, this paper explores the feasibility of the classroom teaching mode of appropriate combination of traditional methods with the multimedia overhead projector. The new teaching mode proves to be successful in that it has greatly improved the students' ability to use English in an all-round way and has obvious advantages over the only traditional method. 展开更多
关键词 traditional method multimedia overhead projector appropriate combination
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基于Projector的球罐表面测地线展开法 被引量:1
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作者 白顺琴 张云飞 石娟 《东华大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第4期490-492,共3页
基于投影工具Projector,提出一种实用的球罐表面展开方法.过球罐表面上一系列测地线将罐体表面划分为小块,提取每一小块的曲面边界曲线作为输入项逐一进行计算、连线并自动生成展开图,最后再集拢到展开后的球罐外表面.与传统的方法相比... 基于投影工具Projector,提出一种实用的球罐表面展开方法.过球罐表面上一系列测地线将罐体表面划分为小块,提取每一小块的曲面边界曲线作为输入项逐一进行计算、连线并自动生成展开图,最后再集拢到展开后的球罐外表面.与传统的方法相比,应用该方法对球罐表面进行展开可以保证焊缝的长度最短,且展开过程形象直观.故球罐的质量、安全性和精度均有所提高. 展开更多
关键词 球面展开 AUTOCAD projector 测地线
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Liquid Crystal Motion Picture Projector 被引量:40
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作者 SHI Yongji(Luoyang Technology College,Luoyang 471003,CHN)Abstract: A liquid crystal moving picture projector and method are described.Light incident on a liquid crystal display-type device is selectively scattered or transmitted by respective portions of liquid crystal display,and a projection mechanism projects an image formed by either such scattered light or such transmitted light.A liquid crystal moving picture projector includes a liquid crystal display for creating characteristics of an image,and projecttion optics for projecting images sequentially created by the display.The display includes a liquid crystal material capable of temporary storing information at respective areas.The temporary storage may be a function of charge storing directly on liquid crystal material.A method of projecting plural images in sequence includes:creating an image or characteristics of an image in a liquid crystal material,storing such image in such liquid crystal material,directing light at such liquid crystal material,projecting such image as a function of light transmitted through or scattered by such liquid crystal material,and creating a further image in such liquid crystal material for subsequent projection. 《Semiconductor Photonics and Technology》 CAS 1997年第3期198-203,共6页
LiquidCrystalMotionPictureProjector①SHIYongji(LuoyangTechnologyColege,Luoyang471003,CHN)Abstract:Aliquidcrys... LiquidCrystalMotionPictureProjector①SHIYongji(LuoyangTechnologyColege,Luoyang471003,CHN)Abstract:Aliquidcrystalmovingpicturep... 展开更多
关键词 Liquid Crystal Display Liquid Crystal projector Projection Optics
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Nonsingularity of the Combinations of Two Orthogonal Projectors 被引量:3
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作者 ZUO Kezheng XIE Tao 《Wuhan University Journal of Natural Sciences》 CAS 2012年第1期7-11,共5页
The invertibility of combinations of two orthogonal projectors aP + bQ - cPQ - dQP is researched by using the CSdecomposition of matrices and properties of orthogonal projectors. The Moore-enrose inverse of the combi... The invertibility of combinations of two orthogonal projectors aP + bQ - cPQ - dQP is researched by using the CSdecomposition of matrices and properties of orthogonal projectors. The Moore-enrose inverse of the combinations is presented under some special conditions. 展开更多
关键词 combinations of two orthogonal projectors CS- decomposition principal angles
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基于ACAD Projector的空间角度计算的3D图解法
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作者 周文 张云飞 《微型电脑应用》 2010年第1期19-21,4,共3页
提出一种基于ACAD Projector的空间角度计算的3D图解法,及其在钻模或夹具设计中的应用。这种处理方法本质上是绕垂直轴旋转法在3D空间的计算机程序实现,可以简化机械加工的工艺设计与操作中的空间角度计算问题,为工程技术领域中空间角... 提出一种基于ACAD Projector的空间角度计算的3D图解法,及其在钻模或夹具设计中的应用。这种处理方法本质上是绕垂直轴旋转法在3D空间的计算机程序实现,可以简化机械加工的工艺设计与操作中的空间角度计算问题,为工程技术领域中空间角度计算方法的研究提供了新的思路。 展开更多
关键词 空间角度 解析计算 3D图解法 ACAD projector
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Multiobjective Optimal Design of Underwater Acoustic Projector with Porous Piezocomposite Active Elements 被引量:1
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作者 A. V. Nasedkin M. S. Shevtsova +2 位作者 J.-C. Liu S.-H. Chang J.-K. Wu 《Journal of Applied Mathematics and Physics》 2013年第6期89-94,共6页
This paper concerns the optimization problem for multilayered ultrasonic transducer with active porous piezoelectric layer. The dependences of the effective moduli for porous piezoelectric material on porosity have be... This paper concerns the optimization problem for multilayered ultrasonic transducer with active porous piezoelectric layer. The dependences of the effective moduli for porous piezoelectric material on porosity have been previously obtained and allowed to decrease the number of design variables. The multiobjective optimization problem based on the Pareto-frontier calculation has been solved using the live-link of finite-element (FE) package Comsol Multiphysics with MATLAB. 展开更多
关键词 POROUS PIEZOCERAMICS MULTIOBJECTIVE Optimization Pareto FRONTIER Multilayered Acoustic projector Underwater Applications
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The Color Calibration across Multi-Projector Display 被引量:4
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作者 Shu Liu Qiuqi Ruan Xiaoli Li 《Journal of Signal and Information Processing》 2011年第2期53-58,共6页
Large plane displays are often achieved by combining tiled imaging elements, which give the appearance of a single, seamless display. However, this is difficult to realize in practical use, since differences in color ... Large plane displays are often achieved by combining tiled imaging elements, which give the appearance of a single, seamless display. However, this is difficult to realize in practical use, since differences in color will make the tiles dis-tinct even if the geometric calibration is perfect. The paper presents an approach of color calibration using cubic B- spline. According to the theory of cubic B-spline, we construct the color transfer function of each projector. This ap-proach reduces the color and photometric non-uniformities to achieve seamless tiled multi-projector display well. Finally, we propose the difference between blending region and overlapping region which can help to achieve a better effect of alpha blending. 展开更多
关键词 Multi-projector DISPLAY Color Calibration ALPHA BLENDING CUBIC B-SPLINE
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Novel method of ordinal bearing estimation for more sources based on oblique projector
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作者 Sun Wei Bai Jianlin Wang Kai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期445-449,共5页
A novel direction of arrival (DOA) estimation method is proposed when uncorrelated, correlated, and coherent sources coexist under color noise field. The uncorrelated and correlated sources are firstly estimated usi... A novel direction of arrival (DOA) estimation method is proposed when uncorrelated, correlated, and coherent sources coexist under color noise field. The uncorrelated and correlated sources are firstly estimated using the conventional spatial spectrum estimation method, then the noise and uncorrelated sources in Toeplitz structure are eliminated using differencing, finally by exploiting the property of oblique projection, the contributions of correlated sources are then eliminated from the covariance matrix and only the coherent sources remain. So the coherent sources can be estimated by the technique of modified spatial smoothing. The number of sources resolved by this approach can exceed the number of array elements without repeatedly estimating correlated sources. Simulation results demonstrate the effectiveness and efficiency of our proposed method. 展开更多
关键词 spatial differencing oblique projector Toeplitz property direction of arrival estimation
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Expansion Formulas for Orthogonal Projectors onto Ranges of Row Block Matrices
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作者 Yongge TIAN Yufu WANG 《Journal of Mathematical Research with Applications》 CSCD 2014年第2期147-154,共8页
We give in this note some expansion formulas for the orthogonal projectors onto the range of the row block matrix [ A, B ], and use the expansion formulas to examine relations among the orthogonal projectors onto the ... We give in this note some expansion formulas for the orthogonal projectors onto the range of the row block matrix [ A, B ], and use the expansion formulas to examine relations among the orthogonal projectors onto the ranges of A, B and [A, B]. In particular, we present some identifying conditions for a pair of orthogonal projectors of the same size to commute. 展开更多
关键词 Moore-Penrose inverse orthogonal projector EQUALITY INEQUALITY rank formula.
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基于Projector的曲面展开程序开发与应用
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作者 顾燕 程洋 葛常清 《淮阴工学院学报》 CAS 2017年第1期17-20,共4页
基于AutoCAD Projector软件,可简便地编制计算机程序,自动绘制可展曲面的展开图。计算每一小块曲面的边界曲线,分点数增加到足够多。最后连线生成展开图,并存放有关数据,以满足机床加工的需要。与传统方法相比,不仅可以提高设计效率,还... 基于AutoCAD Projector软件,可简便地编制计算机程序,自动绘制可展曲面的展开图。计算每一小块曲面的边界曲线,分点数增加到足够多。最后连线生成展开图,并存放有关数据,以满足机床加工的需要。与传统方法相比,不仅可以提高设计效率,还可以提高加工精度和生产效率,是当前计算机辅助设计与制造中的一种实际工艺手段。 展开更多
关键词 AUTOCAD projector 二次开发 曲面展开
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Partial Ordering of Range Symmetric Matrices and M-Projectors with Respect to Minkowski Adjoint in Minkowski Space 被引量:1
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作者 D. Krishnaswamy Mohd Saleem Lone 《Advances in Linear Algebra & Matrix Theory》 2016年第4期132-145,共15页
In this paper, we obtain some new characterizations of the range symmetric matrices in the Minkowski Space M by using the Block representation of the matrices. These characterizations are used to establish some result... In this paper, we obtain some new characterizations of the range symmetric matrices in the Minkowski Space M by using the Block representation of the matrices. These characterizations are used to establish some results on the partial ordering of the range symmetric matrices with respect to the Minkowski adjoint. Further, we establish some results regarding the partial ordering of m-projectors with respect to the Minkowski adjoint and manipulate them to characterize some sets of range symmetric elements in the Minkowski Space M. All the results obtained in this paper are an extension to the Minkowski space of those given by A. Hernandez, et al. in [The star partial order and the eigenprojection at 0 on EP matrices, Applied Mathematics and Computation, 218: 10669-10678, 2012]. 展开更多
关键词 Partial Order Minkowski Adjoint Minkowski Inverse Range Symmetric M-projectors
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On Nonsingularity and Group Inverse of Linear Combinations of Generalized and Hypergeneralized Projectors
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作者 CHEN Yinlan ZUO Kezheng XIE Tao 《Wuhan University Journal of Natural Sciences》 CAS 2014年第6期469-476,共8页
In this paper, some conditions for the nonsingularity and group inverses of linear combinations of generalized and hypergeneralized projectors are established. Moreover, some formulae for the inverses and group invers... In this paper, some conditions for the nonsingularity and group inverses of linear combinations of generalized and hypergeneralized projectors are established. Moreover, some formulae for the inverses and group inverses of them are derived. The work of this paper extends some previous results. 展开更多
关键词 inverse group inverse generalized projectors hypergeneralized projectors
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Computing Radial Distortion of Projector Magnetic Lenses by Analytical Method
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作者 OdayA. Hussein Ayad A. A1-Ani Bahaa A. H. Jawad 《Journal of Physical Science and Application》 2016年第1期167-173,共7页
The radial distortion of projector magnetic lenses with field distributions in the form of inverse law has been theoretically studied using analytical method. The radial distortion coefficient can be expressed explici... The radial distortion of projector magnetic lenses with field distributions in the form of inverse law has been theoretically studied using analytical method. The radial distortion coefficient can be expressed explicitly in term of Bessel function of fraction order Therefore, analytical formulae for radial distortion coefficient of each projector magnetic lenses in this article have derived to computation these coefficients. Also, the dimensionless quality factors for radial distortion are calculated to estimate the performance of image in electron microscope. The results of calculations show that the increasing of order of multipole (n) leads to increase the radial distortion coefficient. 展开更多
关键词 Radial distortion projector magnetic lens analytical method and Bessel function.
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A Modified Newton Method Based on the Metric Projector for Solving SOCCVI Problem
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作者 Hao Liu Juhe Sun Li Wang 《Journal of Applied Mathematics and Physics》 2022年第4期1036-1054,共19页
In this paper, based on the second-order sufficient condition, the Clarke's generalized Jacobian of the Karush-Kuhn-Tucker system of the second-order cone constrained variational inequality (SOCCVI) problem that i... In this paper, based on the second-order sufficient condition, the Clarke's generalized Jacobian of the Karush-Kuhn-Tucker system of the second-order cone constrained variational inequality (SOCCVI) problem that is nonsingular is proved by us. A modified Newton method with Armijo line search is presented. Three illustrative examples are given to show how the modified Newton method works. 展开更多
关键词 Second-Order Cone Variational Inequality Metric projector Second-Order Sufficient Condition
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Runco X-200i Projector
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作者 马峰 庄宏道(摄影) 《现代音响技术》 2013年第6期94-99,共6页
显示芯片:单片16:9Super Onyx^TM DMD^TM ,3D ready 物理分辨力:1920×1080(1080p) 画面尺寸(16:9):推荐78″~112″
关键词 RUNCO X-200i projector 投影机 品牌 硬件 软件
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超萤射——闹钟projector
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《广东电脑与电讯》 2003年第09M期41-41,共1页
关键词 闹钟 projector 收音机 功能
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基于反格雷码辅助相移法的高鲁棒三维测量
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作者 冯云 李佩伍 +3 位作者 伍文蕾 吕健宇 刘晓军 陈良洲 《光学精密工程》 北大核心 2025年第1期1-12,共12页
为了解决结构光三维测量系统受测量环境干扰、被测物体几何特性等因素造成的稳定性不强、精度不高等问题,对该系统的投影编码方式、投影加速等算法进行研究,提升系统稳定性与精度。根据结构光系统稳定性不强的问题提出了正反互补格雷码... 为了解决结构光三维测量系统受测量环境干扰、被测物体几何特性等因素造成的稳定性不强、精度不高等问题,对该系统的投影编码方式、投影加速等算法进行研究,提升系统稳定性与精度。根据结构光系统稳定性不强的问题提出了正反互补格雷码结合相移法。考虑投影张数造成的时间消耗较长等问题,提出了合成图案并行加载方法缩短投影时间。其次,考虑被测物体几何特性造成的光线遮挡与阴影问题,提出双投影单相机系统结构扩大测量视场范围,消除阴影等现象。最后,与互补格雷码结合相移法、多频外差法进行性能比对,证明了所提方法的有效性。实验表明,所提方法的系统稳定性与整体性能较优,合成图案并行加载相比未改进前投影效率提升55.51%,测量标准差为0.014 mm。所提方法极大地提升了系统稳定性,性能优于传统编码方法。 展开更多
关键词 三维测量 反格雷码 相移法 投影加速 双投影单相机
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Approximative compactness and continuity of metric projector in Banach spaces and applications 被引量:5
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作者 HUDZIK Henryk KOWALEWSKI Wojciech WISLA Marek 《Science China Mathematics》 SCIE 2008年第2期293-303,共11页
First we prove that the approximative compactness of a nonempty set C in a normed linear space can be reformulated equivalently in another way.It is known that if C is a semi-Chebyshev closed and approximately compact... First we prove that the approximative compactness of a nonempty set C in a normed linear space can be reformulated equivalently in another way.It is known that if C is a semi-Chebyshev closed and approximately compact set in a Banach space X,then the metric projectorπC from X onto C is continuous.Under the assumption that X is midpoint locally uniformly rotund,we prove that the approximative compactness of C is also necessary for the continuity of the projectorπC by the method of geometry of Banach spaces.Using this general result we find some necessary and sufficient conditions for T to have a continuous Moore-Penrose metric generalized inverse T^+,where T is a bounded linear operator from an approximative compact and a rotund Banach space X into a midpoint locally uniformly rotund Banach space Y. 展开更多
关键词 approximative compactness CONTINUITY metric projector midpoint locally uniformly rotundity 46B20
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