优化传输栅下电势分布改善四管像素的电荷转移效率

提出了一种通过优化传输栅下沿电荷转移路径的电势分布来提高电荷转移效率的方法。通过使用非均匀掺杂传输管沟道,形成了传输管沟道内部的电势分布梯度。通过对R1区与传输栅的交叠长度,R1区的掺杂剂量,防穿通注入（APT）与传输栅交叠长度的调整,减小了传输管沟道与箝位光电二极管（PPD）连接区域的电子势垒与电子势阱,增强了二者的电势连接。仿真结果显示,剩余电荷占总电荷的比例由1/104减小至1/107,转移时间由500 ns缩短为110 ns。这意味电荷转移效率得到了提高。     

A new adaptive switching filter with directional impulse detection

A novel adaptive switching filter （ASF） based on directional detection is proposed for denoising the images that are highly corrupted by impulse noise. The proposed algorithm employs an efficient noise detection mechanism. It first employs an efficient method to estimate the differences between the current pixel and its neighbors aligned with 28 directions. The current noise pixel is replaced by a median or a mean value within an adaptive filter window with respect to different noise densities. Experimental results show that the proposed approach can not only achieve very low miss-detection ratio and false-alarm ratio even up to high noise corruption, but also preserve the detailed information of an image very well.     

Optimal Hankel-norm approximation of continuous-time linear systems

A problem on optimal approximation of continuous-time linear systems is studied. The performance measure (error) is chosen to be the spectral norm of the difference between the Hankel operators associated with the original system and the approximant. It is shown that the Hankel operators associated with continuous-time systems and the Hankel matrices associated with discrete-time systems are related by an interesting correspondence property via bilinear transforms. This fact is then used to derive the continuous-time results (theory and algorithms) from the established discrete-time ones. Some simple examples are presented.This research was supported by the Army Research Office under Grant No. DAAG 29-79-C-0054, and by the National Science Foundation Grant No. ENG-7908673, and by the Office of Naval Research under Contract No. N000-14-81-K-0191.Formerly with the Department of Electrical Engineering-Systems, University of Southern California, Los Angeles, California 90007, USA     

An ADPCM Receiver for NTSC Composite Video Signals

An ADPCM codec for carrying one broadcast quality NTSC color TV channel at a bit rate of 42.9 Mb/s has been proposed. The system uses 3 fsc sampling, adaptive intrafield contour prediction, adaptive quantization., 4/8-bit dual length coding, and horizontal blanking interval suppression techniques. The receiver of.the video codec is designed and implemented in ECL for recovery of the original signal. The receiver accepts.a 42.9 Mb/s serial data stream with a synchronous clock from the transmitter. The receiver detects the line synchronization code, demultiplexes the audio signal and video signal, and generates the horizontal blanking patterns which have been removed at the transmitter side. The 4/8-bit dual length code is decoded and fed to the ADPCM reconstruction loop to obtain the reconstructed active video signal. The generated horizontal blanking pattern is multiplexed with the reconstructed video=signal and sent through a D/A converter to form the reconstructed analog NTSC composite video signal.     

Copolymerization of tetrahydrofuran and propylene oxide

Summary Copolymerization of tetrahydrofuran and propylene oxide catalyzed by modified H₂SO₄.SO₃ system has been studied. Sodium perchloride was used to replace perchloric acid as co-catalyst. The copolymerization rate was obviously accelerated when using the new H₂SO₄.SO₃–NAClO₄ catalyst system. The reaction became less sensitive to the moisture.     

立式聚合釜气液传质特性的研究

本文旨在开发新一代聚四氟乙烯立式反应釜。分别在纯水-氧、乳化剂水溶液-氧两个体系中,用纯氧物理吸收法测定了H/D=1.27的釜的传质容量系数K_La,分析了两体系K_La差别的原因,并对实验结果进行了关联。研究表明,水体系的K_La,是乳液体系的2.5倍,桨型、安装位置等参数对传质有明显影响。在H/D≤1.27的釜中以单层三叶船舶推进器为最佳桨型。     

Glass–Crystal Transition in II-IV-V2 Semiconducting Compounds

The crystallization behavior of amorphous CdGe_xAs₂, where the x values were varied from 0 to 1.2, was studied in order to document the effect of germanium on the amorphous structure. The glass-forming tendency of amorphous CdGe_xAs₂ was evaluated by Hruby's criterion. The crystallization mechanism of each group was proposed, interpreting DSC, XRD, EDS, and TEM data, interactively. The crystallization behavior appeared as two distinct groups: those based on the CdAs₂ structure and those on the CdGeAs₂ structure (chalcopyrite), depending on Ge content. Ge atoms were found to suppress a glass-to-glass exothermic transformation to higher temperatures in the CdAs₂ group, and crystallization in both groups. Proposed models of amorphous structure from previous investigators, measuring the radial distribution function, magnetic susceptibility, and macroscopic density, were correlated to the crystallization studies herein. A model of the transformation of glass structure with increasing Ge content from a CdAs₂ to a CdGeAs₂-like structure was established by extrapolation of experimental results indicating this behavior in crystalline CdGe_xAs₂ compounds with varying x .     

3-D structure-property relationships in rolltruded polymers. Part II: Anisotropic yielding and deformation in triaxially oriented polymers

Rolltrusion, a single step solid state deformation process, has been successfully applied to isotactic poly(propylene), iPP, to produce unique 3-D properties. Mechanical property enhancement not only occurs in the principal draw direction, but also in the transverse directions. A systematic series of standard (ASTM) tensile and compressive experiments were made on well oriented materials supporting this claim. Tensile testing was also performed on dumb-bell shaped specimens cut at various angles to the main deformation direction. A variety of observations were made during testing. Deformation bands, anisotropic yielding, and ductile-to-brittle behavior were observed. These results are presented along with a morphological model that has been developed to account for the behavior of these unique triaxially oriented polymers.     

南京互动电视平台的建设与运营

本文介绍了南京广电网络互动电视平台的总体戎麒南京广电网络有限责任公司数字电视中心副经理发展战略、设计建设特点和业务运营思路,详细阐述了互动电视技术系统建设中的关键技术选择、技术创新点和业务宣传营销实践中的理念和策略.