中国科学院机构知识库网格系统: 检索

Determination of optimum process parameters in gas-assisted injection molding (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Electrical Information and Mechatronics, ICEIM2011, December 23, 2011 - December 25, 2011, Jiaozuo, China
Zi K.; Chen L.

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With finite element analysis software Moldflow numerical simulation and studies about FM truck roof handle were conducted on gas-assisted injection molding process. The influences of melt pre-injection shot gas pressure delay time and melt temperature were observed by using multi-factor orthogonal experimental method. According to the analysis of the factors' impact on evaluation index the optimized parameter combination is obtained. Therefore the optimization design of technological parameters is done. The results show that during the gas-assisted injection molding optimum pre-injection shot is 94% gas pressure is 15MPa delay time is 0.5s melt temperature is 240 C. This study provided a more practical approach for the gas-assisted injection molding process optimization.

Three-sample rotation vector algorithm with angular rate input (EI CONFERENCE) 会议论文 OAI收割
2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China
作者: Zhang Y.

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In order to research the attitude algorithm with angular rate input under the conical motion a optimal threesample rotation vector algorithm based on single-step Newton backward interpolation is proposed. Using the principle of limited rigid body rotation and the characteristic of angular rate input three-sample rotation vector algorithm is derivated. To minimum attitude errors three-sample rotation vector algorithm is optimized. Three angular rate extraction methods of singlestep entire sample recursion multi-step entire sample and singlestep Newton backward interpolation are proposed. Under the condition of conical motion with semi-cone angle 3 and angular frequency 2rad/s simulation is done. The simulation results show that single-step Newton backward interpolation is superior to the other two methods and its maximum error peak is 0.01 error drift rate is 0.036/h. Experiments in three-axis flying turntable with the same parameters are carried out and the results show that error drift rates of three-channels are less than those of traditional quaternion which are 13.53% 12.08% and 23.68% lower respectively. It also verified that the new algorithm can perform a high accuracy under the conical motion. 2011 IEEE.

Sort optimization algorithm of median filtering based on FPGA (EI CONFERENCE) 会议论文 OAI收割
2010 International Conference on Machine Vision and Human-Machine Interface, MVHI 2010, April 24, 2010 - April 25, 2010, Kaifeng, China
作者: Li S.

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The traditional sorting algorithm of median filtering is optimized according to the hardware structure features of FPGA. FPGA is used to acquire the data parallelly for comparing the data of the same column in the median filtering window. Comparing results shared by adjacent filter window are saved temporarily to match the new round of median filtering by using FPGA internal resources. This method can reduce the comparing times from current 21 down to 13 and improve the algorithm efficiency nearly 40%.The experimental results prove that the optimized algorithm can filter a 1K1K gray-level image in about 20ms which ensure the proposed algorithm can be applied in the real-time image median filtering system. 2010 IEEE.

Optimization on motion estimation algorithm based on H. 264 (EI CONFERENCE) 会议论文 OAI收割
2010 3rd International Conference on Advanced Computer Theory and Engineering, ICACTE 2010, August 20, 2010 - August 22, 2010, Chengdu, China
Wen X.; Li G.

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Motion estimation is a very important part of video compression. As a result of using precision of motion vector in H.264 encoder the computational cost increases rapidly and motion estimation is the most time-consuming stage. In this paper based on the UMHexagonS algorithm an optimized algorithm is proposed based on the dynamic search window selection big hexagon and small hexagon search mode respectively which saves motion estimation time effectively with a little quality loss. Experiments with some typical video sequences show that compared to the original UMHexagonS algorithm this new algorithm can save about 17.851 % motion estimation time and reduce the complexity of original scheme as well as enhance the real time performance of encoder and almost has no changes in the reconstructed picture quality and bitrates. 2010 IEEE.

Novel method for optimizing polishing tool-path in CCOS based on weighted-iterative algorithm (EI CONFERENCE) 会议论文 OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China
作者: Zhang X.-J.; Wang X.; Wang X.; Wang X.; Wang X.-K.

收藏 | 浏览/下载：40/0 | 提交时间：2013/03/25

In Computer Controlled Optical Surfacing (CCOS) polishing tool-path is the base of solving other control parameters such as dwell time. In order to improve the fabrication results of polishing off-axis aspheric a novel method to optimize the tool-path is discussed in this paper. The optimizing method named weighted-iterative algorithm is according to the balance principle of the particle system. The power factor of each dwell point represents the requirement of dwell density. Considering the factors which influence the polishing result the power factors cosist of three elements include constant error distribution and dwell distance of workpiece edge. The tool-path is solved by numerical iterative method. In the end an error data is simulated with actual parameters using the matrix-based algorithm with two different tool-paths. The one is X-Y uniform spacing model and the other one is to optimize it based on the first. The comparison shows that the results of the optimized one are much better than traditional one especially the rms convergence rate. Theory of the algorithm is simple and exercisable and it satisfies practical requirement as well. 2009 SPIE.

Optimization procedure for design of heliostat field layout of a 1MWe solar tower thermal power plant (EI CONFERENCE) 会议论文 OAI收割
Solid State Lighting and Solar Energy Technologies, November 12, 2007 - November 14, 2007, Beijing, China
作者: Zhang H.; Zhang H.

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A procedure for designing and optimizing heliostat field layout of solar tower thermal power plant is developed. The ray tracing is used for the calculation of the optical efficiency of field. The mathematical theory of the calculation is derived. The parametric search algorithm which allows variation of the field parameters within a specified range is used for the optimization of field. The field layout is made automatically according to the no-blocking loss condition and the heliostats are located at the positions where the annual incident cosine value is higher. In this way the blocking and cosine losses are lowered. Because the optimization of the distance between fore-and-aft two rows of heliostat is avoided the computer time is reduced effectively. Using this procedure the heliostat field of a 1MWe solar tower power plant was designed. Four modes of layout including North-South cornfield North-South stagger Radial cornfield and Radial stagger were experimented and optimized respectively. The comparison of the field efficiency for the four optimized results was made. It is concluded that the North-South cornfield layout is the optimal decision for the 1MWe solar tower power plant.

Wideband two-port beam splitter of a binary fused-silica phase grating 期刊论文 OAI收割
appl. optics, 2008, 卷号: 47, 期号: 22, 页码: 4004, 4008
Wang Bo; 周常河; Feng Jijun; Ru Huayi; 郑将军

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1550 nm Applications. Beam interferences Beam splitters Coated films Damage thresholds Grating profiles High efficiencies Holographic recordings Incident waves Inductively coupled plasma dry etchings Littrow Low coefficient of thermal expansions Modal methods Optical elements Optimized using Phase gratings Physical mechanisms Practical Wave analyses Wide-band transmissions Wideband Wideband spectrums

Geometry parameter optimization of large cross-sectional S-shaped bent rib waveguides for silicon based optical switches 期刊论文 OAI收割
chinese physics letters, 2007, 卷号: 24, 期号: 3, 页码: 744-746
Li ZY (Li Zhi-Yong); Liu JW (Liu Jing-Wei); Yu JZ (Yu Jin-Zhong)

收藏 | 浏览/下载：110/0 | 提交时间：2010/03/29

摘要: By using a genetic algorithm geometry parameters of large cross-sectional S-bend rib waveguides are optimized aiming at the least total loss when the propagation loss is considered. Optimized results are presented as an example of S-bend rib waveguides based on silicon-on-insulator (SOI) 4 x 4 optical switches. The value of 2dB/cm is given to the propagation loss according to the experimental results. The simulation results indicate that the total loss drops from 1.0002dB down to 0.4375dB without considering a lateral offset. If the offset is adopted the total loss reduces from 0.5463dB to 0.2365dB. In addition the effect of the rib height ratio on the loss is analysed and the optimal ratio is obtained to be 0.55.

Study on color model conversion for camera with neural network based on the combination between second general revolving combination design and genetic algorithm (EI CONFERENCE) 会议论文 OAI收割
ICO20: Illumination, Radiation, and Color Technologies, August 21, 2005 - August 26, 2005, Changchun, China
作者: Li Z.; Zhou F.; Wang C.; Li Z.

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Munsell color system is selected to establish the mutual conversion between RGB and L*a*b* color model for camera. The color luminance meter and CCD camera synchronously measure the same color card XYZ value is gotten from the color luminance meter the training error is 0.000748566 it can show that the method combining second general revolving combination design with genetic algorithm can optimize the hidden-layer structure of neural network. Using the data of testing set to test this network and calculating the color difference between forecast value and true value the color picture captured from CCD camera is expressed for RGB value as the input of neural network and the L*a*b* value converted from XYZ value is regarded as the real color value of target card which the difference is not obvious comparing with forecast result the maximum is 5.6357 NBS namely the output of neural network. The neural network of two hidden-layers is considered the minimum is 0.5311 NBS so the second general revolving combination design is introduced into optimizing the structure of neural network and the average of color difference is 3.1744 NBS. which can carry optimization through unifying project design data processing and the precision of regression equation. Their mathematics model of encoding space is gained and the significance inspection shows the confidence degree of regression equation is 99%. The mathematics model is optimized by genetic algorithm optimization solution is gotten and function value of the goal is 0.0007168. The neural network of the optimization solution is trained

Multiwavelet based multispectral image fusion for corona detection (EI CONFERENCE) 会议论文 OAI收割
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
作者: Wang X.; Yang H.-J.; Sui Y.-X.; Yan F.; Yan F.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

Image fusion refers to the integration of complementary information provided by various sensors such that the new images are more useful for human or machine perception. Multiwavelet transform has simultaneous orthogonality symmetry compact support and vanishing moment which are not possible with scalar wavelet transform. Multiwavelet analysis can offer more precise image analysis than wavelet multiresolution analysis. In this paper a new image fusion algorithm based on discrete multiwavelet transform (DMWT) to fuse the dual-spectral images generated from the corona detection system is presented. The dual-spectrum detection system is used to detect the corona and indicate its exact location. The system combines a solar-blind UV ICCD with a visible camera where the UV image is useful for detecting UV emission from corona and the visible image shows the position of the corona. The developed fusion algorithm is proposed considering the feature of the UV and visible images adequately. The source images are performed at the pixel level. First a decomposition step is taken with the DMWT. After the decomposition step a pyramid for each source image in each level can be obtained. Then an optimized coefficient fusion rule consisting of activity level measurement coefficient combining and consistency verification is used to acquire the fused coefficients. This process reduces the impulse noise of UV image. Finally a new fused image is obtained by reconstructing the fused coefficients using inverse DMWT. This image fusion algorithm has been applied to process the multispectral UV/visible images. Experimental results show that the proposed method outperforms the discrete wavelet transform based approach.