二维离散余弦变换的一种新的快速算法

本文介绍了二维离散余弦变换（ＤＣＴ）的一种新的快速算法，对于Ｎ×Ｎ ＤＣＴ（Ｎ＝２＾ｍ），只需用Ｎ个一维ＤＣＴ和若干加法运算。与常规的行－列法相比，所需的乘法运算量减少了一半，也比其它的快速算法的乘法运算量要少，而加法运算量基本上是相同的。     

小N点二维离散余弦变换的快速算法

本文提出了一种二维旋转因子的分解算法．并以此提出了一种小Ｎ点二维离散余弦变换（２Ｄ—ＤＣＴ）的快速算法,可比传统的２Ｄ—ＤＣＴ算法节约４２％的乘法,加法数几乎相同．     

一种计算机快速二维DCT算法

二维离散余弦变换（２Ｄ－ＤＣＴ）广泛用于数字图像处理中，特别是图像的数据压缩，二维ＤＣＴ的常规算法是行一列法，对于计算（Ｎ×Ｎ）ＤＣＴ，需要计算２Ｎ个一维ＤＣＴ。本文利用三角函数的公式，并将二维输入数据划分为Ｎ个不同的数据集，提出了一种快速算法。该算法对于计算（Ｎ×Ｎ）ＤＣＴ只需要计算Ｎ个一维ＤＣＴ，运算量是常规算法的一半。该算法的计算结构具有高度规则性，只要求执行实数运算。     

二维离散余弦变换的一种新的快速算法

本文介绍了二维离散余弦变换(DCT)的一种新的快速算法。对于NN DCT(N=2m),只需用N个一维DCT和若干加法运算。与常规的行-列法相比,所需的乘法运算量减少了一半,也比其它的快速算法的乘法运算量要少,而加法运算量基本上是相同的。     

一种快速计算DCT的递归算法及其硬件实现

给出了一种快速计算离散余弦变换的递归算法结构。该结构给出了用两个２＾Ｎ－１点ＤＣＴ去代替２＾ 蝶ＣＴ，在此基础上，提出了一种简单实用的用开关控制的ＤＣＴ／ＩＤＣＴ相结合的实现结构，在该 ，仅有正系数的乘法运算和基本的蝶形运算。     

分离M维DFT快速算法

本文提出了一种新的多维信号ＤＦＴ快速算法，该算法是将多维ＤＦＴ转变成多组一维奇频率ＤＦＴ进行运算，那么其运算量主要取决于一维奇频率ＦＦＴ算法，同时，这有很强的结构，可实现同址运算，文中例举了二维信号时，它与多项式算法的比较，结果是实数据时，两者相同，复数据时，本文算法比文献在加法运算量方面略优，文中还给出了三维四维的运算量。     

在频域内做运动补偿的改进公式及其计算复杂度分析

本文改进了文献［１］中给出的在ＤＣＴ域做运动补偿的计算公式,代之以漂亮的分块矩阵形式,并找出了两分块矩阵之间存在的关系,使用新的公式及得到的关系可以将运算复杂度从每计算一个ＤＣＴ系数需２５６次乘法及１９２次加法［１］减至少于５６次乘法及９３次加法．实验结果表明,使用这一公式重建的ＤＣＴ系数和使用常规ＭＰＥＧ－２解码器恢复的空域图象再做ＤＣＴ变换得到的系数是完全一致的。     

二维Hartley变换的分裂向量基算法

本文给出了二维离散Hartley变换的一个快速算法.本算法在计算过程中按时间抽取逐级进行,不需要中间寄存装置和矩阵转置运算,比[1]的算法,具有更简单的运算结构,易于在计算机中实现。比[2]的向量基算法,在4096×4096点实数列时,可节省32％的乘法运算量,加法运算量稍有减少。     

一种简化的Burg功率谱估计算法

本文提出了一种简化的 Burg 功率谱估计算法,该方法将乘法运算量减少约40%,加法运算量减少约25%,谱估计的性能与 Burg 方法的结果一致。文中分析了 Anderson 算法中导致|am,m|>1的原因。     

视频压缩在视频监控系统中的应用

本文介绍了视频服务器的组成及常见的图象压缩标准,通过深入研究Ｈ．２６３视频压缩算法,针对视 频监控应用提出三点改进。研究了ＤＣＴ／ＩＤＣＴ快速算法,并直接采用ＭＭＸ实现了ＤＣＴ／ＩＤＣＴ和运动向量 估计等大运算量模块,完整地实现了整套基于Ｈ．２６３的软件监控系统,在实际中得到较好的应用。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.