H.264可分级编码技术介绍

H.264标准以其高效的编解码技术,为视频编码的发展带来了革命性的变化。近年来,随着视频业务的增多,相关的分级编码技术不断发展。为了适应需求,H.264标准也增加了可分级编码的扩展部分。本文首先简要回顾了H.264标准的相关概念,然后对H.264标准的时域、空域和质量可分级编码作了介绍和分析。最后揭示了各种分级编码技术的特点。     

基于子带/小波分解的视频编码可分级性研究

视频编码的可分级性是MPEG-4标准视频部分所要求的重要功能之一.本文提出了一种基于子带/小波分解的可分级性结构,以支持视频编码的空域分层、时域分层以及混合分层,并通过实验验证了它的有效性.     

基于H.264/SVC的视频加密技术研究

随着网络的不断普及和发展,视频数据在网络中有了越来越多的应用,随之也提出了视频安全的问题,通过视频加密可以很好地解决此问题。文中分析了目前主流的H.264SVC标准所采用的可分级视频编码技术,根据视频分级编码特点选取关键信息进行分层加密,实现不同级别的视频加密。同时,所提方案采用了序列密码进行加密,具有较高的安全性。试验结果表明:该方案具有安全性高、复杂度适中、实时性好等特点。     

一种低码率下视频分级B帧量化参数的分配方法

分级B帧编码结构是H.264/AVC和可伸缩视频编码中实现时域可分级所采用的高效编码方法。在低码率下,按照提案JVT-P014中的分级B帧量化参数(QP)分配方案进行编码会产生较大的视频质量波动,严重影响视频的主观质量。针对这一问题,提出一种新的分级B帧QP分配方法。该方法考虑了人眼视觉暂留特性,能够有效减小低码率下视频帧之间的质量波动。实验结果证明在低码率编码条件下,该算法与JVT-P014方案相比减少视频质量波动10%以上,并能同时维持整体率失真编码性能基本不变。     

用于无线视频传输的分级编码策略研究

研究一个运用分级编码进行点对点和点对多点无线视频传输的方案,该方案简化了呼叫接纳控制机制,采用区分处理、有条件重传等策略来提高无线视频传输的可靠性和有效性,最后给出一个采用分级编码的无线视频传输模型.     

小波可分级视频编码技术综述

主要对小波图像视频可分级编码方法进行了分析和评述,并探讨了目前小波可分级视频编码技术的研究热点和今后的发展方向.     

无线异构网络中的低复杂度分级视频传输技术

针对无线异构网络中进行视频无线传输遇到的网络拥塞、传输丢失等问题,提出了低编码复杂度分级编解码传输方案,基于逐级优化理论和可分级编码理论,设计了视频分级编码策略:利用小波变换后的不同分解层不同子带构成基本层(Base Layer,BL)和三个增强层,获得了码率分级和质量分级的特性.实验结果证明,随着不同层的更新,视频分级系统的解码质量和整体率失真性能都逐级改善.该传输方案实现了在信道条件动态变化的无线网络环境下仍能流畅传输并接收到有用信息,适用于信道条件不稳定的无线异构网络.     

无线Mesh网络视频流媒体自适应编码与传输控制研究

讨论了无线Mesh网络（WMN）中视频流媒体自适应编码与传输控制的问题,包括视频流媒体可分级编码的必要性和实现原理,传输过程中的主动丢包策略,并讨论了对其进一步改进的方法。使读者对WMN中视频流媒体的自适应编码和传输控制有概括性的了解。     

面向可靠传输的多描述可分级编码

多描述可分级视频编码技术是一种新技术,它是随着Internet及无线流视频应用的迅速发展而产生的,多描述可分级编码的特点是不但具有很好的容错性,而且它适宜于接收端异构的网络应用,适应带宽变化,并具有鲁棒性。本文对多描述可分级编码技术的特点进行了分析,介绍了几种实现多描述可分级编码的策略。     

基于网络编码的分级视频权限控制方法

提出一种基于随机线性网络编码的可分级视频流的权限控制算法,该算法充分考虑了网络编码技术和可分级技术的有机结合,从数据包加密和分配2个方面详细阐述了其实现机制,给出了基于全局编码向量的加密和分层的视频证书认证算法。提出的方法具有运算复杂度低和易于实现的优点。仿真结果证明提出的方法可以有效且简便地控制视频的使用权限。     

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.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

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.     

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.     

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.     

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.     

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.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.