Block multiple measurement vectors (BMMV) is a reconstruction algorithm that can be used to recover the support of block K-joint sparse matrix X from Y = ΨX + V. In this paper, we propose a sufficient condition for a...Block multiple measurement vectors (BMMV) is a reconstruction algorithm that can be used to recover the support of block K-joint sparse matrix X from Y = ΨX + V. In this paper, we propose a sufficient condition for accurate support recovery of the block K-joint sparse matrix via the BMMV algorithm in the noisy case. Furthermore, we show the optimality of the condition we proposed in the absence of noise when the problem reduces to single measurement vector case.展开更多
The kinematic error model of a 6-DOF space robot is deduced, and the cost function of kinematic parameter identification is built. With the aid of the genetic algorithm (GA) that has the powerful global adaptive pro...The kinematic error model of a 6-DOF space robot is deduced, and the cost function of kinematic parameter identification is built. With the aid of the genetic algorithm (GA) that has the powerful global adaptive probabilistic search ability, 24 parameters of the robot are identified through simulation, which makes the pose (position and orientation) accuracy of the robot a great improvement. In the process of the calibration, stochastic measurement noises are considered. Lastly, generalization of the identified kinematic parameters in the whole workspace of the robot is discussed. The simulation results show that calibrating the robot with GA is very stable and not sensitive to measurement noise. Moreover, even if the robot's kinematic parameters are relative, GA still has strong search ability to find the optimum solution.展开更多
The purpose of this study was to construct bases for exploring the process of skill acquisition from the viewpoint of eye-hand coordination. The information obtained from eye-gaze is closely related to physical moveme...The purpose of this study was to construct bases for exploring the process of skill acquisition from the viewpoint of eye-hand coordination. The information obtained from eye-gaze is closely related to physical movements in any activity. It is important to establish a method to measure eye-hand coordination for extracting skilled elements and understanding the skill acquisition process. Using a system which consists of an eye mark recorder and a three-dimensional location measurement device, a method for measuring eye-hand coordination was proposed on the basis of the simultaneous measurement of eye-gaze and brush tip locations. After describing the measurement algorithm, the eye-hand coordination during calligraphy was exemplified. More concretely, using such a system, an attempt was made to show that the relationship between the line of eye-gaze and the brush tip stroke was different between a novice and an expert. In such a way, we suggested that the proposed method is promising for exploring the process of skill acquisition.展开更多
A predictive search algorithm to estimate the size and direction of displacement vectors was presented.The algorithm decreased the time of calculating the displacement of each pixel.In addition,the updating reference ...A predictive search algorithm to estimate the size and direction of displacement vectors was presented.The algorithm decreased the time of calculating the displacement of each pixel.In addition,the updating reference image scheme was used to update the reference image and to decrease the computation time when the displacement was larger than a certain number.In this way,the search range and computational complexity were cut down,and less EMS memory was occupied.The capability of proposed search algorithm was then verified by the results of both computer simulation and experiments.The results showed that the algorithm could improve the efficiency of correlation method and satisfy the accuracy requirement for practical displacement measuring.展开更多
A new representation method is first presented based on priority roles. According to this method, each entry in the chromosome indicates that in the procedure of the Giffler and Thompson (GT) algorithm, the conflict...A new representation method is first presented based on priority roles. According to this method, each entry in the chromosome indicates that in the procedure of the Giffler and Thompson (GT) algorithm, the conflict occurring in the corresponding machine is resolved by the corresponding priority role. Then crowding-measure multi-objective evolutionary algorithm (CMOEA) is designed, in which both archive maintenance and fitness assignment use crowding measure. Finally the comparisons between CMOEA and SPEA in solving 15 scheduling problems demonstrate that CMOEA is suitable to job shop scheduling.展开更多
According to the test data of subdivision errors in the measuring cycle of angular measuring system, the characteristics of subdivision errors generated by this system are analyzed. It is found that the subdivision er...According to the test data of subdivision errors in the measuring cycle of angular measuring system, the characteristics of subdivision errors generated by this system are analyzed. It is found that the subdivision errors are mainly due to the rotary-type inductosyn itself. For the characteristic of cyclical change, the subdivision errors in other measuring cycles can be compensated by the subdivision error model in one measuring cycle. Using the measured error data as training samples, combining GA and BP algorithm, an ANN model of subdivision error is designed. Simulation results indicate that GA reduces the uncertainty in the training process of the ANN model, and enhances the generalization of the model. Compared with the error model based on the least-mean-squared method, the designed ANN model of subdivision errors can achieve higher compensating precision.展开更多
In this paper, we study optimal recovery (reconstruction) of functions on the sphere in the average case setting. We obtain the asymptotic orders of average sampling numbers of a Sobolev space on the sphere with a G...In this paper, we study optimal recovery (reconstruction) of functions on the sphere in the average case setting. We obtain the asymptotic orders of average sampling numbers of a Sobolev space on the sphere with a Gaussian measure in the Lq (S^d-1) metric for 1 ≤ q ≤ ∞, and show that some worst-case asymptotically optimal algorithms are also asymptotically optimal in the average case setting in the Lq (S^d-1) metric for 1 ≤ q ≤ ∞.展开更多
The climate warming is mainly due to the increase in concentrations of anthropogenic greenhouse gases, of which CO_2 is the most important one responsible for radiative forcing of the climate. In order to reduce the g...The climate warming is mainly due to the increase in concentrations of anthropogenic greenhouse gases, of which CO_2 is the most important one responsible for radiative forcing of the climate. In order to reduce the great estimation uncertainty of atmospheric CO_2 concentrations, several CO_2-related satellites have been successfully launched and many future greenhouse gas monitoring missions are planned. In this paper, we review the development of CO_2 retrieval algorithms, spatial interpolation methods and ground observations. The main findings include: 1) current CO_2 retrieval algorithms only partially account for atmospheric scattering effects; 2) the accurate estimation of the vertical profile of greenhouse gas concentrations is a long-term challenge for remote sensing techniques; 3) ground-based observations are too sparse to accurately infer CO_2 concentrations on regional scales; and 4) accuracy is the primary challenge of satellite estimation of CO_2 concentrations. These findings, taken as a whole, point to the need to develop a high accuracy method for simulation of carbon sources and sinks on the basis of the fundamental theorem of Earth's surface modelling, which is able to efficiently fuse space- and ground-based measurements on the one hand and work with atmospheric transport models on the other hand.展开更多
A modified regularization algorithm with a more proper operator was proposed for the inversion of particle size distribution (PSD) from light-scattering data in a laser particle sizer based on the Mie scattering pri...A modified regularization algorithm with a more proper operator was proposed for the inversion of particle size distribution (PSD) from light-scattering data in a laser particle sizer based on the Mie scattering principle. The Generalized Cross-Validation (GCV) method and the L-curve method were used for deter- mining the regularization parameter. The Successive Over-Relaxation (SOR) iterative method was used to increase the exactness and stability of the converged result. The simulated results based on the modified algorithm are in a good agreement with the experimental data measured for nine standard particulate samples, their mixtures as well as three natural particulate materials with irregular shapes, indicating that this modified regularization method is not only feasible but also effective for the simulation of PSD from corresponding light-scattering data.展开更多
文摘Block multiple measurement vectors (BMMV) is a reconstruction algorithm that can be used to recover the support of block K-joint sparse matrix X from Y = ΨX + V. In this paper, we propose a sufficient condition for accurate support recovery of the block K-joint sparse matrix via the BMMV algorithm in the noisy case. Furthermore, we show the optimality of the condition we proposed in the absence of noise when the problem reduces to single measurement vector case.
基金supported by National Natural Science Foundation of China(No.60775049).
文摘The kinematic error model of a 6-DOF space robot is deduced, and the cost function of kinematic parameter identification is built. With the aid of the genetic algorithm (GA) that has the powerful global adaptive probabilistic search ability, 24 parameters of the robot are identified through simulation, which makes the pose (position and orientation) accuracy of the robot a great improvement. In the process of the calibration, stochastic measurement noises are considered. Lastly, generalization of the identified kinematic parameters in the whole workspace of the robot is discussed. The simulation results show that calibrating the robot with GA is very stable and not sensitive to measurement noise. Moreover, even if the robot's kinematic parameters are relative, GA still has strong search ability to find the optimum solution.
文摘The purpose of this study was to construct bases for exploring the process of skill acquisition from the viewpoint of eye-hand coordination. The information obtained from eye-gaze is closely related to physical movements in any activity. It is important to establish a method to measure eye-hand coordination for extracting skilled elements and understanding the skill acquisition process. Using a system which consists of an eye mark recorder and a three-dimensional location measurement device, a method for measuring eye-hand coordination was proposed on the basis of the simultaneous measurement of eye-gaze and brush tip locations. After describing the measurement algorithm, the eye-hand coordination during calligraphy was exemplified. More concretely, using such a system, an attempt was made to show that the relationship between the line of eye-gaze and the brush tip stroke was different between a novice and an expert. In such a way, we suggested that the proposed method is promising for exploring the process of skill acquisition.
文摘A predictive search algorithm to estimate the size and direction of displacement vectors was presented.The algorithm decreased the time of calculating the displacement of each pixel.In addition,the updating reference image scheme was used to update the reference image and to decrease the computation time when the displacement was larger than a certain number.In this way,the search range and computational complexity were cut down,and less EMS memory was occupied.The capability of proposed search algorithm was then verified by the results of both computer simulation and experiments.The results showed that the algorithm could improve the efficiency of correlation method and satisfy the accuracy requirement for practical displacement measuring.
基金This project is supported by National Natural Science Foundation of China(No.60574049, No.70071017).
文摘A new representation method is first presented based on priority roles. According to this method, each entry in the chromosome indicates that in the procedure of the Giffler and Thompson (GT) algorithm, the conflict occurring in the corresponding machine is resolved by the corresponding priority role. Then crowding-measure multi-objective evolutionary algorithm (CMOEA) is designed, in which both archive maintenance and fitness assignment use crowding measure. Finally the comparisons between CMOEA and SPEA in solving 15 scheduling problems demonstrate that CMOEA is suitable to job shop scheduling.
文摘According to the test data of subdivision errors in the measuring cycle of angular measuring system, the characteristics of subdivision errors generated by this system are analyzed. It is found that the subdivision errors are mainly due to the rotary-type inductosyn itself. For the characteristic of cyclical change, the subdivision errors in other measuring cycles can be compensated by the subdivision error model in one measuring cycle. Using the measured error data as training samples, combining GA and BP algorithm, an ANN model of subdivision error is designed. Simulation results indicate that GA reduces the uncertainty in the training process of the ANN model, and enhances the generalization of the model. Compared with the error model based on the least-mean-squared method, the designed ANN model of subdivision errors can achieve higher compensating precision.
基金supported by the National Natural Science Foundation of China(No.11426179)the National Natural Science Foundation of China(Nos.10871132,11271263)+4 种基金the Key Scientific Research Fund of Xihua University(No.z1312624)the Foundation of Sichuan Educational Committee(No.14ZA0112)the Preeminent Youth Fund for School of Science in Xihua Universitythe Beijing Natural Science Foundation(No.1132001)BCMIIS
文摘In this paper, we study optimal recovery (reconstruction) of functions on the sphere in the average case setting. We obtain the asymptotic orders of average sampling numbers of a Sobolev space on the sphere with a Gaussian measure in the Lq (S^d-1) metric for 1 ≤ q ≤ ∞, and show that some worst-case asymptotically optimal algorithms are also asymptotically optimal in the average case setting in the Lq (S^d-1) metric for 1 ≤ q ≤ ∞.
基金supported by the National Natural Science Foundation of China (Grant Nos. 91325204, 41421001)the National High-tech R&D Program (Grant No. 2013AA122003)the National Key Technologies R&D Program (Grant No. 2013BACO3B05)
文摘The climate warming is mainly due to the increase in concentrations of anthropogenic greenhouse gases, of which CO_2 is the most important one responsible for radiative forcing of the climate. In order to reduce the great estimation uncertainty of atmospheric CO_2 concentrations, several CO_2-related satellites have been successfully launched and many future greenhouse gas monitoring missions are planned. In this paper, we review the development of CO_2 retrieval algorithms, spatial interpolation methods and ground observations. The main findings include: 1) current CO_2 retrieval algorithms only partially account for atmospheric scattering effects; 2) the accurate estimation of the vertical profile of greenhouse gas concentrations is a long-term challenge for remote sensing techniques; 3) ground-based observations are too sparse to accurately infer CO_2 concentrations on regional scales; and 4) accuracy is the primary challenge of satellite estimation of CO_2 concentrations. These findings, taken as a whole, point to the need to develop a high accuracy method for simulation of carbon sources and sinks on the basis of the fundamental theorem of Earth's surface modelling, which is able to efficiently fuse space- and ground-based measurements on the one hand and work with atmospheric transport models on the other hand.
基金supported by the Science and Technology Development Planning Program of the Guangzhou City Bureau of Scienceand Technology,China(grant200773-D2091)
文摘A modified regularization algorithm with a more proper operator was proposed for the inversion of particle size distribution (PSD) from light-scattering data in a laser particle sizer based on the Mie scattering principle. The Generalized Cross-Validation (GCV) method and the L-curve method were used for deter- mining the regularization parameter. The Successive Over-Relaxation (SOR) iterative method was used to increase the exactness and stability of the converged result. The simulated results based on the modified algorithm are in a good agreement with the experimental data measured for nine standard particulate samples, their mixtures as well as three natural particulate materials with irregular shapes, indicating that this modified regularization method is not only feasible but also effective for the simulation of PSD from corresponding light-scattering data.