Layered Wyner-Ziv video coding.

Following recent theoretical works on successive Wyner-Ziv coding (WZC), we propose a practical layered Wyner-Ziv video coder using the DCT, nested scalar quantization, and irregular LDPC code based Slepian-Wolf coding (or lossless source coding with side information at the decoder). Our main novelty is to use the base layer of a standard scalable video coder (e.g., MPEG-4/H.26L FGS or H.263+) as the decoder side information and perform layered WZC for quality enhancement. Similar to FGS coding, there is no performance difference between layered and monolithic WZC when the enhancement bitstream is generated in our proposed coder. Using an H.26L coded version as the base layer, experiments indicate that WZC gives slightly worse performance than FGS coding when the channel (for both the base and enhancement layers) is noiseless. However, when the channel is noisy, extensive simulations of video transmission over wireless networks conforming to the CDMA2000 1X standard show that H.26L base layer coding plus Wyner-Ziv enhancement layer coding are more robust against channel errors than H.26L FGS coding. These results demonstrate that layered Wyner-Ziv video coding is a promising new technique for video streaming over wireless networks.     

热声制冷机及其改进实验研究

热声制冷作为一种很有前途的制冷方法，在国内外相关领域引起了极大兴趣。热声制冷机由声发生器、共振管、板叠及高、低温换热器等部分组成。对声驱动器的振动膜及其冷却系统、气体弹簧系统、高、低温换热器进行了初步改进，使制冷机冷端温降从原来的12℃提高到27℃左右，这是目前国内报道的最大温降。     

Gamma-irradiation-induced Ag/SiO2 composite films and their optical absorption properties

Small Ag particles or clusters dispersed mesoporous SiO₂ composite films were prepared by a new method: First the matrix SiO₂ films were prepared by sol-gel process combined with the dip-coating technique, then they were soaked in AgNO₃ solutions followed by irradiation of γ-ray at room temperature and in ambient pressure. The structures of these films were examined by X-ray diffraction (XRD), high-resolution transmission electron microscope (HRTEM), and optical absorption spectroscopy. It has been shown that the Ag particles grown within the porous SiO₂ films are very small, and they are isolated and dispersed from each other with very narrow size distributions. With increasing the soaking concentration and an additional annealing, an opposite peakshift effect of the surface plasmon resonance (SPR) was observed in the optical absorption measurements.     

光通信技术发展的新亮点

自光通信问世以来，经历了研究探索、实用化、推广应用、快速发展等时期，直至2001年，达到急剧发展的高潮。随着世界经济的滑坡，通信行业的不景气，使光通信也进入了寒冷的冬天。实际上，即使在经济低速的时期，光通信的技术依然没有停止发展，而且出现了不少继续将光通信推向前进的新亮点。从技术和应用的角度，简要介绍一些光通信的新技术。     

三江盆地西部藻类地层学特征

本文依据三江盆地西部4口井的藻类分布特征，自下而上划分9个组合，并对各组合的时代及沉积环境进行了探讨。     

煤矿生产、安全调度LED电子大屏幕显示系统的设计

通过比较煤矿生产、安全调度显示方式的优缺点，提出和分析了适合于煤矿生产安全调度的ＬＥＤ电子大屏幕显示系统配置、功能及特点。     

地面反射波谱与卫星磁带记录数据间关系模拟的初步探讨──以冬小麦和土壤为例

根据冬小麦和土壤地面反射波谱测试数据，计算了在卫星高度上与卫星磁带数据相对应波段的辐亮度值，对ＮＯＡＡＡＶＨＲＲ和ＴＭ某些通道的差值绿度植被指数ＤＶＩ、归一化绿度植被指数ＮＤＶＩ和比值绿度植被指数ＲＶＩ的分析，从理论上证明了目前采用ＴＭＤＶＩ＿（４，３）提取冬小麦种植面积和ＮＯＡＡＮＤＶＩ＿（２，１）区分植被和土壤背景的有效性。同时在冬小麦种植面积和长势监测方面提出了一些新建议。     

故县大坝坝基泥化性F_5断层的化学灌浆防渗加固处理

泥化软化性F_5断层是故县大坝坝基范围内最大的一条断层,位于左岸,对左坝肩的稳定极为不利,采用水泥灌浆处理无效,故改用化学灌浆处理。选用EAA化学浆材,采用“优选组合配方综合施灌”的创新施工工艺,效果良好,为今后低渗透性复杂的泥化软化性断层的防渗加固处理,提供了新的依据和途径。     

气体引射器流体动力特性实验研究

在实验装置上对气体引射器计算基本公式进行了实测验证，分析了理论特性曲线的可信度。通过实验，获得一些参数对引射器工况的影响规律。     

CA／PAN中空纤维血浆分离膜的结构与性能

本研究以CA及PAN的共混溶液,通过干-湿法纺丝制取中空纤维,利用共混高聚物各组分在凝固剂中相分离速度的差异,形成具有稳定结构的中空纤维孔膜,该膜用于分离血液中的血浆成分具有良好效果。讨论了成型条件及添加剂等对膜结构、性能的影响,用SEM及图相分析仪、MAP压汞仪及DSC等分析手段,对膜的微孔结构、形态、孔尺寸及中空纤维膜的血浆通量和水通量等进行了系统的考查。