Fabrication of field emission display prototype utilizing printed carbon nanotubes/nanofibers emitters

Carbon nanotubes/nanofibers (CNTs) used as emitters, diode-type field emission display (FED) prototypes of dot matrix and character images were fabricated by low-cost techniques and equipments, respectively. The technical development in the design and fabrication of the cathode, the anode, and the panel, is described. CNTs were produced by a simple, low-cost and easily-controllable thermal chemical vapor deposition. The cathode was prepared by the screen-printing method. The field emission characteristics were enhanced by a heat post-treatment in H₂ gas atmosphere. The panel structure was packaged by a vacuum fluorescent display-like process and vacuum-sealed through an exhaust glass tube. The fully-sealed CNTs FED (c-FED) showed good emission properties. The brightness of 600 cd/m² was achieved from the yellow phosphor at a relatively low applied electric field. The developed technology has a potential practical application in c-FED.     

4H-SiC MESFET肖特基栅接触的界面参数提取

研究了界面态对4H-SiC MESFET的肖特基栅接触的影响.栅接触工艺主要采用Ti/Pt/Au蒸发,经过剥离后形成.基于热电子理论提出了一种参数提取方法,得到界面态密度和界面电容分别为4.386×1013cm-2·eV-1和8.394×10-6F/cm2,这与测量得到的器件端特性一致.     

光传输网规划中光缆芯数及光纤类型确定的影响因素

光传输网是电信网的基础,由于光缆线路系统的特殊性,决定了光传输网规划中光缆芯数及光纤类型的确定尤其重要。     

相位编码信号的多普勒频率补偿方法

利用相位编码信号探测高速运动目标时,存在多普勒频率敏感性问题,需要对多普勒频率进行补偿.补偿支路的增加使得运算量和存储量大大增加,为了减少运算量和存储量,提出一种补偿方法,将MTD置于脉冲压缩之前,通过理论推导和Matlab仿真证明了这一算法的正确性与可行性.     

无机相变信息存储材料研究新进展

硫族化合物合金GeSbTe(GST)和AgInSbTe等相变材料(PCM)已经在光存储技术中得到广泛的应用,用相变电存储器件作为闪存的替代产品已成为国内外研究的热点.与此同时,相变材料在一些领域也取得了新的应用.总结了近年来国内外在相变材料的存储机制、光/电存储性能的改进以及新应用等方面的最新研究成果,并展望了相变材料的研究前景.     

一种平衡设计压控振荡器和自动频率校准的快速锁定宽带频率综合器

A wideband fractional-N frequency synthesizer is implemented in a 65 nm CMOS process.It employs a wideband LC voltage-controlled oscillator(VCO) with optimized VCO gain(KVCO/and a sub-band step to improve automatic frequency calibration(AFC) efficiency at negligible expense of phase noise performance.An agile AFC is realized by direct mapping based on the division ratio,and optional redundant counting and comparing calibration is introduced accommodating PVT variations,which samples the reference clock using the prescaled VCO output as a discriminating clock.A charge pump with switched charging current is adopted to compensate for the loop bandwidth variation.Measurement results show this directly-mapped AFC locates the target sub-band in 100 ns and only needs 1.2 s for redundant calibration.The frequency synthesizer spans a frequency range from 0.62 to 1.52 GHz,with phase noise of-86 dBc/Hz at 10 kHz offset and-122 dBc/Hz at 1 MHz offset while consuming 9.76 mA from a 1.2 V supply.     

国产JRAX1000型反熔丝FPGA应用演示系统设计

为了实现进口元器件国产化替代,采用中国电科五十八所自行研制的抗辐射百万门级反熔丝FPGA和64Mbit抗辐射SRAM设计了一套综合演示系统.系统主要功能包含触摸屏控制、图像采集、音频播放、电机控制等功能.通过系统的软硬件设计、功能调试、时序优化,阐述国产JRAX1000型反熔丝FPGA的应用经验,有助于后续此产品广泛应...     

A Link Between Integrals and Higher‐Order Integrals of SPN Ciphers

Integral cryptanalysis, which is based on the existence of (higher‐order) integral distinguishers, is a powerful cryptographic method that can be used to evaluate the security of modern block ciphers. In this paper, we focus on substitution‐permutation network (SPN) ciphers and propose a criterion to characterize how an r‐round integral distinguisher can be extended to an (r+1)‐round higher‐order integral distinguisher. This criterion, which builds a link between integrals and higher‐order integrals of SPN ciphers, is in fact based on the theory of direct decomposition of a linear space defined by the linear mapping of the cipher. It can be directly utilized to unify the procedure for finding 4‐round higher‐order integral distinguishers of AES and ARIA and can be further extended to analyze higher‐order integral distinguishers of various block cipher structures. We hope that the criterion presented in this paper will benefit the cryptanalysts and may thus lead to better cryptanalytic results.     

Stereo Video Retargeting with Representative Seams in a Group of Stereoscopic Frames

The important requirements for stereo video retargeting are threefold: keeping temporal coherence, preventing depth distortion, and minimizing shape distortions of the retargeted video. To meet these requirements, the left and right video sequences are divided into groups of frames (GoFs), where the GoF is a basic unit for the seam carving and we assign a set of fixed seams for all frames within the GoF. To determine the fixed seams for each GoF, we need to find the GoF boundary in the video first. Then, the representative frame for each GoF is generated by considering the spatial saliency and temporal coherence. Also, the confidence of the stereoscopic correspondence between the left and right frames is considered to prevent depth distortion.