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排序方式: 共有843条查询结果,搜索用时 15 毫秒
91.
The development of a high information capacity Chinese character generator,which is called the Chinese character tube is described.It is a high capacity,electron beam-addressed,read-only memory.Information capacity of one tube is more than one megabit.This kind of Chinese character generator has the advantage of small size,high capacity and cost-effective.It can be widely applied to various Chinese character information processing systems. The working principle is described briefly.The experimental results of tube Type Ⅰ(one that stores 512 Chinese characters with 48×48 dot matrix per Chinese character)are given. 相似文献
92.
Mihai Sima Sorin Cotofaná Jos T. J. Van Eijndhoven Stamatis Vassiliadis Kees Vissers 《The Journal of VLSI Signal Processing》2005,39(3):195-212
This paper presents a TriMedia processor extended with an IDCT reconfigurable design, and assesses the performance gain such an extension has when performing MPEG-2 decoding. We first propose the skeleton of an extension of the TriMedia architecture, which consists of a Field-Programmable Gate Array (FPGA)-based Reconfigurable Functional Unit (RFU), a Configuration Unit managing the reconfiguration of the RFU, and their associated instructions. Then, we address the computation of the 8 × 8 (2-D) IDCT on such extended TriMedia and propose a scheme to implement the 1-D IDCT operation on the RFU. When mapped on an ACEX EP1K100 FPGA from Altera, the proposed 1-D IDCT exhibits a latency of 16 and a recovery of 2 TriMedia@200 MHz cycles, and occupies 45% of the logic cells of the device. By configuring the 1-D IDCT on the RFU at application launch-time, the IEEE-compliant 2-D IDCT can be computed with the throughput of 1/32 IDCT/cycle. This figure translates to an improvement over the standard TriMedia of more than 40% in terms of computing time when 2-D IDCT is carried out in the framework of MPEG-2 decoding. Finally, the proposed reconfigurable IDCT is compared to a number of existing designs.Mihai Sima was born in Bucharest, Romania. He received the MS degree in Electrical Engineering from Politehnica University of Bucharest, and the Ph.D. degree in Electrical Engineering from Delft University of Technology, The Netherlands. He had been with the Microelectronics Company in Bucharest for 3 years, where he was involved in instrumentation electronics for integrated circuit testing. Subsequently, he joined the Telecommunications Department of Politehnica University of Bucharest, where he had been involved in digital signal processing and speech recognition for 6 years. More recently, he had been with the Faculty of Electrical Engineering, Mathematics, and Computer Science, Delft University of Technology, where he worked on reconfigurable architectures for mediaprocessing domain. He is currently an assistant professor with the Department of Electrical and Computer Engineering, University of Victoria, B.C., Canada. His research interests include computer architecture, reconfigurable computing, embedded systems, digital signal processing, and speech recognition.Sorin D. Coofan was born in Mizil, Romania. He received the MS degree in Computer Science from the Politehnica University of Bucharest, Romania, and the Ph.D. degree in Electrical Engineering from Delft University of Technology, The Netherlands. He had worked with the Research & Development Institute for Electronic Components (ICCE) in Bucharest for a decade, being involved in structured design of digital systems, design rule checking of ICs layout, logic and mixed-mode simulation of electronic circuits, testability analysis, and image processing. He is currently an associate professor with the Faculty of Electrical Engineering, Mathematics, and Computer Science, Delft University of Technology, The Netherlands. His research interests include computer arithmetic, parallel architectures, embedded systems, reconfigurable computing, nano-electronics, neural networks, computational geometry, and computer aided design.Jos T.J. van Eijndhoven was born in Roosendaal, The Netherlands. He studied Electrical Engineering at the Eindhoven University of Technology, The Netherlands, obtaining the M.Sc. and Ph.D. degrees in 1981 and 1984, respectively, for a work on piecewise linear circuit simulation. Then, he became a senior research member in the design automation group of the Eindhoven University of Technology. In 1986 he spent a sabbatical period at the IBM Thomas J. Watson Research Laboratory, Yorktown Heights, New York, for research on high level synthesis. In 1998 he joined Philips Research Laboratories in Eindhoven, The Netherlands, to work on the architectural design of programmable multimedia hardware and the associated mapping of media processing applications.Stamatis Vassiliadis was born in Manolates, Samos, Greece. He is a professor with the Faculty of Electrical Engineering, Mathematics, and Computer Science, Delft University of Technology, The Netherlands. He has also served in the faculties of Cornell University, Ithaca, NY, and the State University of New York (S.U.N.Y.), Binghamton, NY.He hadworked for a decade with IBM in the AdvancedWorkstations and Systems laboratory in Austin TX, the Mid-Hudson Valley Laboratory in Poughkeepsie, NY, and the Glendale Laboratory in Endicott, NY. In IBM he was involved in a number of projects regarding computer design, organizations, and architectures and the leadership to advanced research projects. A number of his design and implementation proposals have been implemented in commerciallyavailable systems and processors including the IBM 9370 model 60 computer system, the IBM POWER II, the IBM AS/400 Models 400, 500, and 510, Server Models 40S and 50S, the IBM AS/400 Advanced 36, and the IBM S/390 G4 and G5 computer systems. For his work, he received numerous awards including 23 levels of Publication Achievement Awards, 15 levels of Invention Achievement Awards and an Outstanding Innovation Award for Engineering/Scientific Hardware Design in 1989. In 1990 he has been awarded the highest number of USA patents in IBM, six of his 70 USA patents being rated with the highest patent ranking in IBM.Kees A. Vissers graduated the Delft University of Technology, receiving his M.Sc. in 1980. He started directly with Philips Research Laboratories in Eindhoven where he was involved in highlevel simulation and high-level synthesis. He had been heading the research on hardware/software co-design and system level design for many years, and had a significant contribution to the TriMedia VLIW processor. From 1987 till 1988 he was a visiting researcher at Carnegie Mellon University, Pittsburgh, Pennsylvania, with the group of Don Thomas. He is currently a Research Fellow with University of California at Berkeley, Department of Electrical Engineering and Computer Sciences. His research interests include video processing, embedded media processing systems, and reconfigurable computing. 相似文献
93.
94.
基于侧边抛磨光纤光栅双反射峰的折射率传感器 总被引:2,自引:0,他引:2
介绍了一种利用具有双布拉格反射峰效应的侧边抛磨光纤光栅(SPFBG)进行折射率测量的新型光纤折射率传感器.该传感器基于由轮式侧边抛磨法加工而成的侧边抛磨光纤光栅,通过将折射率液覆盖一部分抛磨区的方法在一根光纤光栅上获得两个布拉格反射峰.这两个布拉格反射峰差值与覆盖材料折射率有关,而与光纤光栅所受应力与环境温度无关,因此用这两个布拉格反射峰差值作为测量量对折射率测量,可减小应力与环境温度的影响,实现高精度的折射率传感测量.实验表明,当维持环境温度恒定时,光纤光栅轴向应变在线性变化范围内,该传感器测量折射率时不受应力与温度变化的影响.折射率液在1.4298~1.4479范围内,该传感器的折射率测量分辨率为0.0001. 相似文献
95.
Meifeng He Lei Liu Yating Wu Zhixin Tang Wenbin Hu 《Journal of Coatings Technology and Research》2009,6(3):407-411
A process for surface modification of AZ91D magnesium alloy has been carried out in AlCl3–NaCl molten salts melt at 573 K for 7 h. The process was used to form a diffusion alloying layer on the surface of the sample
to improve corrosion resistance. The diffusion alloying layer was mainly composed of Mg–Al intermetallic compounds. The continued
immersion test in 5% NaCl solutions displayed that molten salt diffusion-treated specimen had better corrosion resistance
compared to the untreated AZ91D specimen. The polarization test indicated that the Mg–Al intermetallic compounds of the layer
were an effective corrosion barrier to decrease the corrosion rate for AZ91D magnesium alloy when exposed to 3.5% NaCl solutions.
The microhardness values of the Mg–Al intermetallic compounds were higher than those of the substrate. 相似文献
96.
97.
无损检测和结构健康监测是保障工业生产安全、降低维护成本的重要技术。在结构健康监测领域,原位测量仪器的长期稳定性尤为重要。首先介绍电磁、超声无损检测在厚度检测的应用现状,针对随后讨论厚度无损检测检测仪器精度长期稳定性问题。对厚度无损检测仪器现在长期使用过程中的精度变化规律进行研究,探讨三种测厚仪器的工作原理、精密度和准确度与仪器的稳定性的关系。采用三种厚度测量仪器(超声测厚仪、涂覆层测厚仪与楼板测厚仪)测量预标定样本的仪器试验测量方法,得到五年测量数据。再通过分析数据的年平均误差、相对误差和变化速率来讨论电涡流测厚仪、超声测厚仪的长期稳定性,并进行三类仪器间的比较,分析各类型仪器的特点。结果显示电涡流厚度测量仪器具有相对较好的长期稳定性;超声测厚仪和楼板测厚仪精密度维持能力受时间影响,仪器精密度逐年下降,准确度也趋于不稳定。为电磁无损检测技术应用到结构健康监测领域,自校准和补偿奠定了基础。 相似文献
98.
以新疆地区自然发酵的辣椒酱为材料,在厌氧条件下采用富集培养法、溶钙圈法对产酸乳酸菌进行初筛;通过测定菌株的产酸能力和NaCl耐受能力进行复筛;通过形态观察、生理生化试验及分子生物学技术对耐盐乳酸菌进行鉴定。结果表明,筛选得到7株产酸乳酸菌,其中,3株产酸能力强、耐盐性能好,分别为菌株B、SS、T,均可耐受7%NaCl。菌株B、SS及T均被鉴定为植物乳酸杆菌(Lactobacillus plantarum)。耐盐性乳酸菌的筛选对提高自然发酵辣椒酱的品质起着重要作用。 相似文献
99.
目的:以低筋小麦粉为主要原料,添加北虫草粉、鸡蛋液、黄奶油、白砂糖等制作北虫草蛋卷。方法:通过单因素实验和响应面试验构建Box-Behnken多元回归模型,对北虫草蛋卷的配方进行优化,通过TMS-PRO质构仪进行质构特性测定,根据食品安全国家标准测定产品性能指标。结果:以低筋小麦粉总量为基准,当北虫草粉添加量为6%、鸡蛋液添加量为25%、白砂糖添加量为30%、黄奶油添加量为37%,在此条件下,北虫草蛋卷感官评分为91.0。各项性能指标均符合国家安全标准,且具有良好的持水性与持油性,北虫草蛋卷硬度为34.03±0.49 N;黏着性为-1.34±0.01 N·s;凝聚性为0.13±0.01 mJ;咀嚼性为3.36±0.23 N;弹性为0.76±0.01 mm。结论:相较于全粉蛋卷,北虫草蛋卷具有高蛋白、高虫草素、高持水性、低脂肪和低持油性的特点,营养价值更优。 相似文献
100.
枯草芽孢杆菌固态发酵玉米粉的研究 总被引:4,自引:1,他引:3
以玉米粉为原料,选用枯草芽孢杆菌进行固态发酵,研究适宜的发酵条件及发酵对玉米粉营养成分的影响。试验结果表明,适宜的发酵条件为:发酵时间72 h,接种量15%,料水比为1∶0.4,硫酸铵添加量为1.5%。发酵产物中淀粉含量显著下降,降解率达到37.76%(70.48%~43.87%)。淀粉相对分子质量显著下降(1.07×106~3.86×105)。可溶性糖含量提高了171.9%(11.96%~32.52%),其中还原糖含量提高了2.1倍(3.94%~12.22%),糊精含量提高了3.22倍(3.77%~15.94%)。枯草芽孢杆菌发酵玉米粉能显著提高可溶性糖的含量,从而改善饲用品质。 相似文献