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101.
分析了基于家庭网络开展多网络业务融合的多种形式和优势,并对基于家庭网络的多网络业务融合的实现方式进行了探讨。  相似文献   
102.
固体铝电解电容器用导电高分子制备工艺进展   总被引:1,自引:0,他引:1  
依据近年的相关专利,综述了用于固体铝电解电容器的导电高分子的最新制备工艺,介绍了导电高分子固体铝电解电容器的结构,详细描述了制备导电高分子的两种主要方法——化学聚合和电化学聚合——及其进展历程。介绍了新颖掺杂剂的发现与使用,对各种工艺的特点进行了评述。  相似文献   
103.
A component of the Atmospheric Infrared Sounder (AIRS) instrument system is the AIRS/Visible Near InfraRed (Vis/NIR) instrument. With a nadir ground resolution of 2.28 km and four channels, the Vis/NIR instrument provides diagnostic support to the infrared retrievals from the AIRS instrument and several research products, including surface solar flux studies. The AIRS Vis/NIR is composed of three narrowband (channel 1: 0.40-0.44 /spl mu/m; channel 2: 0.58-0.68 /spl mu/m, and channel 3: 0.71-0.92 /spl mu/m) and one broadband (channel 4: 0.49-0.94 /spl mu/m) channel, each a linear detector array of nine pixels. It is calibrated onboard with three tungsten lamps. Vicarious calibrations using ground targets of known reflectance and a cross-calibration with the Moderate Resolution Imaging Spectroradiometer (MODIS) augment the onboard calibration. One of AIRS Vis/NIR's principal supporting functions is the detection of low clouds to flag these conditions for atmospheric temperature retrievals. Once clouds are detected, a cloud height index is obtained based on the ratio (channel 2 - channel 3)/channel 1 that is sensitive to the partitioning of water vapor absorption above and below clouds. The determination of the surface solar radiation flux is principally based on channel 4 broadband measurements and the well-established relationship between top-of-the atmosphere (broadband) radiance and the surface irradiance.  相似文献   
104.
We demonstrate the use of an injection-locked Fabry-Pe/spl acute/rot laser diode with electronic feedback for base-rate clock recovery in N/spl times/10 Gb/s optical time-division-multiplexing (OTDM) systems. Injection-locking enhances the resonance frequency of the laser and the electrical feedback achieves strong resonance at the base-rate frequency of the injected data streams, enabling ultrastable electrical clock signal generation at the base rate of 10 GHz. Experimental demonstrations for clock recovery at 10 GHz from 40-Gb/s OTDM data streams and 4-1 demultiplexing of the data using the extracted clock after fiber transmission is presented. The timing jitter measured in the recovered electrical clock is less than 0.25 ps.  相似文献   
105.
1 Introduction High power laser diode arrays (LDA) have many advan- tages such as small volume, long working life, high slope efficiency and high optical density, so they have many applications in medical treatment, material pro- cessing, and for the pumping source of solid laser and etc. But unfortunately, the LDA can not be easy to use directly in these fields because of their poor beam quality and extremely asymmetric divergent beams (!x≈ 5°~10°and !y≈20°~35°, for example), so it …  相似文献   
106.
All-buried InP-InGaAsP ring resonators laterally coupled to bus waveguides are demonstrated. The buried configurations offer a lower built-in refractive index step along the resonator periphery, which affords enhanced optical coupling coefficients between the waveguides and reduced scattering losses caused by the resonator sidewall imperfections. Very low optical intensity attenuations of 0.4 cm/sup -1/ and coupling-limited quality factors of greater than 10/sup 5/ are observed from 200-/spl mu/m-radii ring resonators. The measured spectral linewidth is as narrow as 0.0145 nm.  相似文献   
107.
In this letter, we introduce and investigate a new problem referred to as the All Hops Shortest Paths (AHSP) problem. The AHSP problem involves selecting, for all hop counts, the shortest paths from a given source to any other node in a network. We derive a tight lower bound on the worst-case computational complexities of the optimal comparison-based solutions to AHSP.  相似文献   
108.
Optimized combination of chemical agents was selected for sensitive electrochemical detection of dissolved ruthenium tris-(2,2′-bipyridine) (Ru-bipy). The detection was based on the chemical amplification mechanism, in which the anodic current of a redox-active analyte was amplified by a sacrificial electron donor in solution. On indium-doped tin oxide (ITO) electrodes, electrochemical reaction of the analyte was reversible, but that of the electron donor was greatly suppressed. Several transition metal complexes, such as ferrocene and tris-(2,2′-bipyridine) complexes of osmium, iron and ruthenium, were evaluated as model analyte. A correlation between the amplified current and the standard potential of the complex was observed, and Ru-bipy generated the largest current. A variety of organic bases, acids and zwitterions were assessed as potential electron donor. Sodium oxalate was found to produce the largest amplification factor. With Ru-bipy as the model analyte and oxalate as the electron donor, the analyte concentration curve was linear up to 50 μM, with a lower detection limit of approximately 50 nM. Preliminary work was presented in which a Ru-bipy derivative was attached to bovine serum albumin and detected electrochemically. Although the combination of Ru-bipy, oxalate and ITO electrode has been used before for electrochemiluminescent detection of Ru-bipy and oxalate, as well as electrochemical detection of oxalate, its utility in amplified voltammetric detection of Ru-bipy as a potential electrochemical label has not been reported previously.  相似文献   
109.
刘杨 《现代电子技术》2006,29(11):24-26,31
介绍了下行链路中基于循环前缀的单载波直接序列扩频技术(CP/CDMA)。这种技术结合了多载波系统中的循环前缀和频域均衡,具有较低的复杂度。同时保留了单载波系统发射端复杂度低的优点。在时变信道中,利用基于辅助数据的信道估计方法,即每隔一定帧数的数据帧发送一帧训练序列来估计信道。在仿真中使用了信道编码。  相似文献   
110.
介绍了文档数据库Lotus Domino/Notes的特点.对其文档处理的核心,即Notes文档的ID构成机制作了系统剖析.并在此基础上分析了如何在文档复制中运用ID的不同组件以及如何运用API程序访问文档ID等。  相似文献   
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