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
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
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
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
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
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
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
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
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
Based on the differential properties of the smoothing metric projector onto the second-order cone,we prove that,for a locally optimal solution to a nonlinear second-order cone programming problem,the nonsingularity of...Based on the differential properties of the smoothing metric projector onto the second-order cone,we prove that,for a locally optimal solution to a nonlinear second-order cone programming problem,the nonsingularity of the Clarke's generalized Jacobian of the smoothing Karush-Kuhn-Tucker system,constructed by the smoothing metric projector,is equivalent to the strong second-order sufficient condition and constraint nondegeneracy,which is in turn equivalent to the strong regularity of the Karush-Kuhn-Tucker point.Moreover,this nonsingularity property guarantees the quadratic convergence of the corresponding smoothing Newton method for solving a Karush-Kuhn-Tucker point.Interestingly,the analysis does not need the strict complementarity condition.展开更多
A novel see-through virtual retina display(VRD) system is proposed in this Letter. An optical fiber projector is used as the thin-light-beam source, which is modified from a laser scan projector by separating the lase...A novel see-through virtual retina display(VRD) system is proposed in this Letter. An optical fiber projector is used as the thin-light-beam source, which is modified from a laser scan projector by separating the laser sources and the scan mechanical structure. A synthetic aperture method is proposed for simple, low-cost fabrication of a volume holographic lens with large numerical aperture. These two key performance-enhanced elements are integrated into a lightweight and ordinary-glasses-like optical see-through VRD system. The proposed VRD system achieves a weight of 30g and a diagonal field of view of 60°.展开更多
This paper proposes a depth measurement error model for consumer depth cameras such as the Microsoft Kinect, and a corresponding calibration method. These devices were originally designed as video game interfaces, and...This paper proposes a depth measurement error model for consumer depth cameras such as the Microsoft Kinect, and a corresponding calibration method. These devices were originally designed as video game interfaces, and their output depth maps usually lack sufficient accuracy for 3 D measurement.Models have been proposed to reduce these depth errors, but they only consider camera-related causes.Since the depth sensors are based on projectorcamera systems, we should also consider projectorrelated causes. Also, previous models require disparity observations, which are usually not output by such sensors, so cannot be employed in practice. We give an alternative error model for projector-camera based consumer depth cameras, based on their depth measurement algorithm, and intrinsic parameters of the camera and the projector; it does not need disparity values. We also give a corresponding new parameter estimation method which simply needs observation of a planar board. Our calibrated error model allows use of a consumer depth sensor as a 3 D measuring device.Experimental results show the validity and effectiveness of the error model and calibration procedure.展开更多
A light field three-dimensional （3D） display with multi-projectors and a concave screen is proposed. The system sets the viewing area at the center of the concave screen, making viewers enter the center of the syste...A light field three-dimensional （3D） display with multi-projectors and a concave screen is proposed. The system sets the viewing area at the center of the concave screen, making viewers enter the center of the system to watch 3D scene around them. The surrounded 3D scene provides viewers a feast of enhanced immersive experience. The light field principle, rendering algorithm, selection of viewing area and experi- mental results are discussed in the letter, showing the potential of being an all-around-type immersive 3D display by employing more projectors.展开更多
文摘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.
文摘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.
文摘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.
基金supported by the National Natural Science Foundation of China(60601016).
文摘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.
文摘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.
文摘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.
文摘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].
基金the State Committee for Scientific Research,Poland (Grant No.1P03A1127)the National Nature Science Foundation of China (Grant Nos.10471032,10671049)
文摘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.
基金Supported by the Hubei Normal University Research Grant (2008D54)
文摘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.
基金supported by National Natural Science Foundation of China (Grant Nos.10771026,10901094)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry of China
文摘Based on the differential properties of the smoothing metric projector onto the second-order cone,we prove that,for a locally optimal solution to a nonlinear second-order cone programming problem,the nonsingularity of the Clarke's generalized Jacobian of the smoothing Karush-Kuhn-Tucker system,constructed by the smoothing metric projector,is equivalent to the strong second-order sufficient condition and constraint nondegeneracy,which is in turn equivalent to the strong regularity of the Karush-Kuhn-Tucker point.Moreover,this nonsingularity property guarantees the quadratic convergence of the corresponding smoothing Newton method for solving a Karush-Kuhn-Tucker point.Interestingly,the analysis does not need the strict complementarity condition.
基金supported by the 863 Program (No. 2015AA015902)he National Natural Science Foundation of China (No. 61575025)+1 种基金the Fund of the State Key Laboratory of Information Photonics and Optical Communicationsthe Program of Beijing Science and Technology Plan (No. D121100004812001)
文摘A novel see-through virtual retina display(VRD) system is proposed in this Letter. An optical fiber projector is used as the thin-light-beam source, which is modified from a laser scan projector by separating the laser sources and the scan mechanical structure. A synthetic aperture method is proposed for simple, low-cost fabrication of a volume holographic lens with large numerical aperture. These two key performance-enhanced elements are integrated into a lightweight and ordinary-glasses-like optical see-through VRD system. The proposed VRD system achieves a weight of 30g and a diagonal field of view of 60°.
基金supported by the JST CREST“Behavior Understanding based on Intention-Gait Model”project
文摘This paper proposes a depth measurement error model for consumer depth cameras such as the Microsoft Kinect, and a corresponding calibration method. These devices were originally designed as video game interfaces, and their output depth maps usually lack sufficient accuracy for 3 D measurement.Models have been proposed to reduce these depth errors, but they only consider camera-related causes.Since the depth sensors are based on projectorcamera systems, we should also consider projectorrelated causes. Also, previous models require disparity observations, which are usually not output by such sensors, so cannot be employed in practice. We give an alternative error model for projector-camera based consumer depth cameras, based on their depth measurement algorithm, and intrinsic parameters of the camera and the projector; it does not need disparity values. We also give a corresponding new parameter estimation method which simply needs observation of a planar board. Our calibrated error model allows use of a consumer depth sensor as a 3 D measuring device.Experimental results show the validity and effectiveness of the error model and calibration procedure.
基金supported by the National High Technology Research and Development Program of China(Nos.2012AA011902 and 2012AA03A302)the National Natural Science Foundation of China(No.61177015)+1 种基金the National Basic Research Program of China(973 Program)(No.2013CB328802)the Fundamental Research Funds for the Central Universities of China(No.2012XZZX013)
文摘A light field three-dimensional （3D） display with multi-projectors and a concave screen is proposed. The system sets the viewing area at the center of the concave screen, making viewers enter the center of the system to watch 3D scene around them. The surrounded 3D scene provides viewers a feast of enhanced immersive experience. The light field principle, rendering algorithm, selection of viewing area and experi- mental results are discussed in the letter, showing the potential of being an all-around-type immersive 3D display by employing more projectors.
