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Application of Moldflow in gas-assisted injection molding (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Mechatronics and Materials Processing, ICMMP 2011, November 18, 2011 - November 20, 2011, Guangzhou, China
Zi K. M.; Chen L. H.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
Gas-assisted injection molding(GAIM)is a new kind of plastic processing technique. It is one of the most important developments in the injection molding industry. GAIM has many advantages such as lower injection pressure  lower warpage  better surface quality  lower material consumption  and shorten molding cycle time  etc. MPI/Gas module of Moldflow software can be used to simulate the GAIM process to optimize the whole molding process. In this study  the FM new truck interior ceiling handle was analyzed in GAIM process based on the MPI/Gas module. The simulation results showed the gas penetrating time  the contours of plastic layers thickness fraction of the parts and the gas volume fraction changing with time. The results can help technicians to determine the optimum process of the melt injection and the gas injection to ensure the final quality of the parts. 2011 Trans Tech Publications.  
An improved algorithm to generate high quality progressive animation models (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on Biomedical Engineering and Computer Science, ICBECS 2010, April 23, 2010 - April 25, 2010, Wuhan, China
作者:  
Zhao J.;  Zhang S.
收藏  |  浏览/下载:29/0  |  提交时间:2013/03/25
In computer graphics  investigation has been made in many years in progressive models generation to alleviate the workload of visualization processing. However  most of the existing algorithms only focus on static meshes  and very little works are to deal with animation models. In this paper  we propose an improved method for generating progressive multiresolution animation models. By the method we first use a normal deviation parameter to improve the famous QEM method as our basic edge contraction metric to generate a base hierarchy. The sequence of the simplified models is generated progressively from the first frame to the last one. Based on the edge contraction sequence in the previous frame  the contraction order in the current frame is adjusted according to the deformation degree. We demonstrate that our method works efficiently and can generate better approximations with well-preserved features than previous methods. 2010 IEEE.  
An intelligent video surveillance system (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on E-Product E-Service and E-Entertainment, ICEEE2010, November 7, 2010 - November 9, 2010, Henan, China
Gao S.
收藏  |  浏览/下载:18/0  |  提交时间:2013/03/25
This paper presents an intelligent video surveillance system. The system is composed of one or more nodes flexibly according to the application scenarios such as private properties  banks and museums. Each node is an autonomous vision-based device capable to perform intelligent tasks. It is able to digitize and compress the acquired analog video signals in MPEG-4 standard and then transmit the compressed video stream to the control center. At the same time  the node makes use of a statistical approach for real-time detecting moving object and online alarm generation to enable a single human operator to monitor activities over a complex area using a distributed network of active video sensors. The node is implemented on a platform with high performance to ensure that the algorithm is able to run in real-time. Applications demonstrate that the intelligent system has an excellent performance in many scenarios to help people make decisions more accurately and rapidly. 2010 IEEE.  
Micro-motion exposure method based on PZT piezoelectric ceramics (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2009: Material and Device Technology for Sensors, June 17, 2009 - June 19, 2009, Beijing, China
作者:  
Meng Z.;  Meng Z.
收藏  |  浏览/下载:105/0  |  提交时间:2013/03/25
There mainly is laser digital photofinishing technique and digital photofinishing technique based on LCD consisting of TFT and LCOS in the digital photofinishing field at the present time. The former have a good many merit such as wide color gamut  high processing rate  large output size and high brightness  but his cost is very high  his maintain technique being comparatively complex  that result in difficult use for people. The utilization ratio of the latter is low because of lower resolution and lower aperture ratio for LCD  but the digital photofinishing based on LCD have lower cost and higher utilization ration  being suitable for people's current standard of living. Considering above mentioned problem  a micro-motion exposure method based on PZT piezoelectric ceramics used in digital image photofinishing is presented. The two-dimension micro-motion exposure system consisting of PZT piezoelectric ceramics  LCD panel  polarizing film and spring strip is designed. By means of PZT piezoelectric ceramics the LCD panel is removed about the one half of the pixel size of the LCD panel for four times from the original place  at the same time imaging system is exposed four times at the printing paper. The software is used to control the time synchronization  the exposure time and motion range of the LCD panel. The system has advantages such as shorter response time than 0.1seconds  lesser motion error than 0.01 microns  high stability and repeatability. Experimental results show that the proposed micro-motion exposure method improve the picture brightness and enlarge output size  at the meantime reducing the cost of the system. 2009 SPIE.  
Many-to-one encryption and authentication scheme and its application 期刊论文  iSwitch采集
Journal of communications and networks, 2008, 卷号: 10, 期号: 1, 页码: 18-27
作者:  
Lin, Xi-Jun;  Wu, Chuan-Kun;  Liu, Feng
收藏  |  浏览/下载:29/0  |  提交时间:2019/05/10
Research on the support structure of the primary mirror of large-aperture telescope (EI CONFERENCE) 会议论文  OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China
Yang W.; Jingxu Z.
收藏  |  浏览/下载:35/0  |  提交时间:2013/03/25
Large-aperture telescope can be used in surveying battlefield  researching landform  searching object  real-time monitoring  imaging  detecting and identifying spatial targets and so on. A large-aperture telescope for achieving high resolution power is designed to monitor spatial target and image in real time. Real-time monitoring plays an important role in military conflicts. The orbit parameter of object  quantity  geometrical shape parameter and so on can be obtained by detect spatial target. With the development of optical technology  people require larger aperture in optics-electronic (OE) system. By increasing optical aperture  the ability of collecting light and resolution power in the system can be enhanced. But the support structure of the primary mirror of large-aperture telescope will be a very difficult problem. With the increase of primary mirror aperture  the weight of the primary mirror will become larger than before. The root mean square (rms) of the primary mirror is affected by many factors  such as deadweight  deformation of heat  environment and so on. Due to the primary mirror of telescope is an important component of telescope system. By reducing the weight of primary mirror  precision of the system is ensured. During the designing phase  one can consider the supporting project of the primary mirror synthetically and analyze it roundly according to technical requirement of optical system and the effect factors. The final structural design can be reasonable. In an astronomical telescope  the surface of reflector is an important part for collecting dark radiation of celestial bodies. Its surface shape will have an effect on collecting efficiency of telescope radiant energy directly. So the rms must be very high. Optical system of large aperture  small wavelength and small focus can receive maximal light intensity. For ground-based optical astronomical telescope  the design proposed in the paper can satisfy the requirement of the possible minimum atmosphere seeing at astronomical observatory site and exert the use efficiency of the telescope adequately. So the accuracy of the traditional surface of reflector can assure that 90% of all the light energy can be focused on within the angle diameter range of the minimum atmosphere seeing  then 100% of light energy should be focused on the angle diameter range of minimum atmosphere seeing. Because the rms of mirror is very high  precise surface machining and accurate the support of mirror are very important tasks during designing and manufacturing the telescope. In the paper  various support techniques of a large-aperture telescope primary mirror are discussed and a 3.5 meter telescope system at the Starfire Optical Range (SOR) overviewed simply  which was operated by the Directed Energy Directorate of the Air Force Research Laboratory  Kirtland AFB  NM  USA from the ground-based O-E system for the observations of spatial target. We also analyze Theoretical elastic deformation of the Steward Observatory 2.3 meter mirror is analyzed.  
Study on CCD image compression and mass storage (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Liu H.;  Liu H.;  Liu H.
收藏  |  浏览/下载:36/0  |  提交时间:2013/03/25
When CCD camera photographs massive images in the air  it is very important to compress and save CCD image timely and validly. This paper designs the CCD image compression and mass storage system. The one part is image compression: this paper introduces a reduced memory still image compression algorithm based on Listless Zerotree Coding (LZC). Compared with SPIHT  the approach significantly reduced memory requirement and no reducing the quality of the reconstructed image. The other part is image mass storage: this system uses a kind of special hard disk storage devices that can realize faster data transmission to SCSI (Small Computer System Interface) devices even if it separates oneself from PCs. In the faster data acquisition and storage system  data storage is a key technology. Normal approach is saving the data to mass memories  and then processing and saving the data after complete acquisition. The continuous acquisition time is restricted with the storage capacity in the normal method so that it can't receive the requirement of CCD image storage on many occasions. While its price will be geminate increasing  when we increase the storage capacity. So the approach in this paper is better one to use fast disks on data direct mass storage considering the storage capacity  read/write speed and unit cost. The result of the experiment shows that the system has compressed and saved CCD image validly  so it reached the anticipative purpose.  
Detection and tracking of low contrast targets based on integertype lifting wavelet transform (EI CONFERENCE) 会议论文  OAI收割
ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Wang L.;  Wang L.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
This paper presents a method for detecting and tracking of low contrast targets. The new method uses an integer-type lifting wavelet transform and the proposed method doesn't extract patterns similar to a template  but finds parts having the same feature in the targets. We utilize one of integer-type lifting wavelet transforms that contains rounding-off arithmetic for mapping integers to integers. The lifting term contains parameters that are learned by using standard training images of targets. We assume that the targets include many high frequency components. In order to obtain the features of the targets  the lifting parameters are determined by a condition that high frequency components are vanished in wavelet transform. But the condition cannot be determined by the parameters wholly. So  we put an additional condition of minimizing the squared sum of the lifting parameters. The advantage of using integer-type wavelet transform is simple and robust to noise. Simulation illustrated the approach can detect and track the moving targets in dim background. We would test our algorithm in the TV tracking system.  
Research on the nonuniformity correction of linear TDI CCD remote camera (EI CONFERENCE) 会议论文  OAI收割
Advanced Materials and Devices for Sensing and Imaging II, November 8, 2004 - November 10, 2004, Beijing, China
Ya-xia L.; Zhi-hang H.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
Many applications  such as industrial inspection and overhead reconnaissance benefit from line scanning architectures where time delay integration (TDI) significantly improves sensitivity[5]. Images with linear response have become the backbone of the imaging industry. But each pixel of the TDI CCD has unique light sensitivity characteristics. Because these characteristics and the lens of the optical system affect camera's linearization and its performance  they must be removed through calibration. The process by which a CCD image is calibrated is known as nonuniformity correction. This paper discusses several methods of nonuniformity correction[2]. The first is one-point correction technique  which requires only one calibration point. This approach is to shift each curve toward the nominal curve by subtracting the offset from or adding the offset to the average. The second is two-point correction technique  which requires two calibration points. Each point is rotated and aligned so that all the detectors have the same response under the same radiance. The third is multipoint correction. It is recommended that more calibration points be implemented at appropriate regions of the response curve. Depend on the linear photoelectric response of the TDI CCD  we use two-point calibration and the standard deviations for the images are given before and after the correction.  
新型结构模糊控制器的研究 学位论文  OAI收割
工学硕士, 中国科学院自动化研究所: 中国科学院自动化研究所, 1999
邵海峰
收藏  |  浏览/下载:30/0  |  提交时间:2015/09/02