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A review on biomass-derived levulinic acid for application in drug synthesis 期刊论文
CRITICAL REVIEWS IN BIOTECHNOLOGY, 2021, 页码: 34
作者:  Zhang, Mingyue;  Wang, Nan;  Liu, Jianguo;  Wang, Chenguang;  Xu, Ying
收藏  |  浏览/下载：51/0  |  提交时间：2021/10/27
Comparison and simulation of subpixel imaging modes for linear CCD (EI CONFERENCE) 会议论文
2012 3rd International Conference on Information Technology for Manufacturing Systems, ITMS 2012, September 8, 2012 - September 9, 2012, Qingdao, China
Li Y.; He B.; Liu T.
收藏  |  浏览/下载：27/0  |  提交时间：2013/03/25
Subpixel technique of linear CCD is effective to enhance the spatial resolution without increasing the focal length of optics and reducing the pixel size. To compare image quality of two main subpixel imaging modes  quincunx sampling and four-point sampling  a method to quantitatively evaluate image quality of subpixel based on MTF was proposed. The MTF of quincunx and four-point sampling modes were derived. Analytical results shows that theoretical limiting resolution of quincunx sampling and four-point sampling is improved to 1.4 and 1.86 times respectively  and MTF values at Nyquist frequency of two modes are increased by 0.1106 and 0.1679  respectively. MTFA in (0  0.5) of two subpixel imaging modes were calculated and results illustrates that four-point sampling offers much more improvement with image quality than quincunx sampling  at the cost of double amount of data. A model for simulating subpixel imaging using Matlab was established  and simulation results of spoke target verify the theoretical analysis. (2012) Trans Tech Publications  Switzerland.  
DsPIC-based mini gas denseness monitor (EI CONFERENCE) 会议论文
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Yu H.-Z.
收藏  |  浏览/下载：21/0  |  提交时间：2013/03/25
Micro-motion exposure method based on PZT piezoelectric ceramics (EI CONFERENCE) 会议论文
International Symposium on Photoelectronic Detection and Imaging 2009: Material and Device Technology for Sensors, June 17, 2009 - June 19, 2009, Beijing, China
Sun W.-J.; Zhang M.-H.; Meng Z.
收藏  |  浏览/下载：91/0  |  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.  
Multiresolution animated models generation based on deformation distance analysis (EI CONFERENCE) 会议论文
2009 International Conference on Computer Modeling and Simulation, ICCMS 2009, February 20, 2009 - February 22, 2009, Macau, China
Shixue Z.; Enhua W.
收藏  |  浏览/下载：57/0  |  提交时间：2013/03/25
In computer graphics  animated models have been widely used to represent time-varying data. Reducing the models complexly is a common way to overcome the rendering limitations. In this paper  2009 IEEE.  we propose an efficient method for generating multiresolution animated models based on deformation distance analysis. Our method obtains different LOD models by performing iterative edge contraction operations. We use deformation distance to analysis the deformation degree of the triangle planes during the whole animation  and define a deformation weight to be added to the aggregated edge contraction cost. Thus features in areas with large deformation can be preserved well. Besides  we propose a mesh optimization method for dynamic model sequence  which can efficiently improve the temporal coherence and reduce visual artifacts between adjacent frames. The results show our approach is efficient  easy to implement  and good quality animated approximations with well-preserved fine details can be generated at any given frame. copy  
Using bidirectional binary particle swarm optimization for feature selection in feature-level fusion recognition system (EI CONFERENCE) 会议论文
2009 4th IEEE Conference on Industrial Electronics and Applications, ICIEA 2009, May 25, 2009 - May 27, 2009, Xi'an, China
Wang D.; Ge W.; Wang Y.
收藏  |  浏览/下载：16/0  |  提交时间：2013/03/25
In feature-level fusion recognition system  the other is optimizing system sensor design to get outstanding cost performance. So feature selection become usually necessary to reduce dimensionality of the combination of multi-sensor features and improve system performance in system design. In general  there are two main missions. One is improving the recognition correct rate as soon as possible  the optimization is usually applied to feature selection because of its computational feasibility and validity. For further improving recognition accuracy and reducing selected feature dimensions  this paper presents a more rational and accurate optimization  Bidirectional Binary Particle Swarm Optimization (BBPSO) algorithm for feature selection in feature-level fusion target recognition system. In addition  we introduce a new evaluating function as criterion function in BBPSO feature selection method. At the last  we utilized Leave-One-Out method to validate the proposed method. The experiment results show that the proposed algorithm improves classification accuracy by two percentage points  while the selected feature dimensions are less one dimension than original Particle Swarm Optimization approach with 16 original feature dimensions. 2009 IEEE.  
Study on CCD image compression and mass storage (EI CONFERENCE) 会议论文
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
Liu H.; Zhai L.; Xiu J.; Zhao X.
收藏  |  浏览/下载：21/0  |  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.  
Application of photoresist melting method to the fabrication of holographic grating (EI CONFERENCE) 会议论文
ICO20: Optical Devices and Instruments, August 21, 2005 - August 26, 2005, Changchun, China
Li W.; Bayanheshig; Zhang C.; Gao J.; Yu H.; Tang Y.
收藏  |  浏览/下载：58/0  |  提交时间：2013/03/25
A new technique of reducing surface roughness of photoresist grating is presented. In this paper  photoresist melting method  which is low-cost  short-period and easy realization  is presented. In addition  the influence of photoresist melting on the groove profile of the photoresist grating is investigated. Experimental results show that the surface roughness reduces due to surface tension  when developed photoresist is heated to be melting state by this method. In experiment  when the melted photoresist grating is etched by ion beam  the surface relief grating possessing preferable groove profile is obtained on K9 glass substrate  then the surface is evaporated by aluminum using vacuum evaporation  holographic grating with preferable groove profile is successively fabricated.  
Study on optical parts of MOEMS optical switch with low insertion loss (EI CONFERENCE) 会议论文
MEMS/MOEMS Technologies and Applications II, November 10, 2004 - November 12, 2004, Beijing, China
Ming A.; Liang J.; Lan W.; Dong W.; Yao J.; Wang W.; Le Z.; Chen W.; Wang L.
收藏  |  浏览/下载：22/0  |  提交时间：2013/03/25
We study insertion losses of optical switch when the laser beam is propagating during the free space between two single mode fibers (SMFs) and the related assemblage challenges  Then a new packaging structure is developed for the hybrid-integration of free-space MOEMS (micro-opto-electro-mechanical systems) chip with a silicon micromachined submount to improve alignment accuracy. The submount is designed to accommodate various free-space MOEMS chips with minimal active optical alignment  thus reducing the packaging cost. The silicon submount has a central recess to place the MOEMS chip in  sixteen V-grooves for optical fibers  and micropits for micro ball lenses  all bulk micromachined at the same time by a single anisotropic wet etching step. A corner compensation technique is employed to prevent erosion of the convex corners  where different geometries meet. Through this assembling method  the fiber  micro ball lens can be aligned preciously thus reduced lateral and angular misalignment between them. Then total insertion losses can be decreased.  
A LITERATURE REVIEW OF R&D BEHAVIOR AND ITS EFFECT 会议论文
CHINA'S LOGISTICS AND SUPPLY CHAIN RESEARCH IN PERIOD OF ECONOMY TRANSFORMATION, 32-38, 2012
作者:  Zhang, HJ;  Zhang, Y
收藏  |  浏览/下载：0/0  |  提交时间：2020/01/05

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