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1.
线阵CCD数据的高速采集与存储   总被引:14,自引:3,他引:11  
在各种高精度线阵CCD应用系统中,需要对像元输出信号进行快速采样、存储及数据处理。CCD数据采集的采样速率不仅与A/D转换器的转换速率等因素有关,同时还与数据传送方式密切相关。以高精度线阵CCD TCD1501D和高速A/D转换器TLC5510为例.详细分析了CCD和A/D转换器的工作时序,采用CPLD设计方法,将CCD的输出信号进行高速A/D转换,并将结果直接存入存储器中。  相似文献   

2.
本文介绍一种可根据输入信号幅度自动变换系统前置放大器系数、以提高A/D转换器分辨能力的方法。此方法适合于量程宽而分辨能力分段可变的场合。以提高8位A/D转换器ADC0809的分辨力为例、详细说明电路设计原理。  相似文献   

3.
给出由单片数模转换器构成程控增益放器的设计示例及其与微机的接口电路,并实验测试该放大器的性能。这种放大器在低频智能仪器及工业控制等方面有广泛用途。  相似文献   

4.
选择线性热敏电阻组成的脉宽电路 ,将脉宽作为控制计数的时间 ,由晶振产生某一标准频率的脉冲信号 ,通过分频以及计算译码驱动送显示。可直接显示温度数字。该设计省去 A/ D转换器 ,结构简单 ,成本低廉 ,灵敏度高 ,稳定可靠 ,使用方便。  相似文献   

5.
设计了一个脉冲频率调制限流比较器电路,在轻载时使芯片进入脉冲频率调制工作模式,因此能够大幅度的提高电源管理芯片的效率.经分析和仿真表明:该比较器延迟小,具有简单、实用、可靠性高等优点.  相似文献   

6.
通常固定增益的放大器在兼顾大的动态范围和较高的小信号精度的情况下很难满足预期的要求。本文针对增益为 2 0~ 2 3倍的可编程阶码放大器 AD5 2 6集成片 ,摆脱传统的设计方法 ,提出一种反馈式程控放大电路。该电路能够在瞬时调整信号的放大增益 ,具有很高的精度和较大的动态范围 ,能够在模数转换前端处理中发挥重要作用。  相似文献   

7.
本文介绍了TMS320C25高速接口电路的设计方法,并以高速A/D接口为例,说明接口电路设计中的一些技巧。这对充分利用TMS320C25的硬件资源有非常重要的意义。  相似文献   

8.
简述了压力传感器的温度补偿技术以及如何选择恒流源和数据放大器,重点对气压计的系统电路进行了设计。安装调试,结果证明,线性很好,完全符合设计要求。  相似文献   

9.
介绍利用8031单片机及外围电路,设计高性/价比的有线传呼器的设计思想、技术性能及设计技巧,给出了程序框图及部分电路图。  相似文献   

10.
介绍了GSM协议转换器的软硬件设计及实现.利用西门子TC35射频模块和MCU智能控制功能,设计具有标准的GSM协议接口和RS232接口电路.该协议转换器能将控制中心的控制信息或数据发到GSM 网络的任何终端,同时也能将远程采集到的数据转换成标准的GSM数据格式并通过GSM网络传输到控制中心.  相似文献   

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12.
Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area.  相似文献   

13.
Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter.  相似文献   

14.
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied  相似文献   

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16.
《山地科学学报》2014,(4):I0004-I0009
<正>AIMS AND SCOPE(Editorial Policy)The Journal of Mountain Science(JMS)is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the world,such as the Tibetan Plateau,the Himalayas,the Alps,the Andes,the Rockies and many other mountain ranges of our planet.  相似文献   

17.
<正>The Journal of Mountain Science(JMS),founded in2004,is an international English-language journal on mountain sciences.JMS is supervised by the Chinese Academy of Sciences(CAS),sponsored by the Chengdu Institute of Mountain Hazards and Environment,CAS,published by Science Press China,and distributed by Springer exclusively throughout the world(excluding Mainland China).The JMS is published bimonthly,fulltexted in SpringerLink and CNKI,indexed/abstracted by  相似文献   

18.
Using the NCEP/NCAR reanalysis monthly 500 hPa height data on a 2.5 latitude-longitude grid and 1°×1° sea ice data,the polar vortex area,intensity index and arctic sea ice area index are calculated respectively,and the meridional distribution,period variation and the abrupts in the long range trend are analyzed to study their relationship.The results show that the meridional distribution of sea ice and polar vortex h-ave distinctive difference,the relative positions of them are different in the eastern and western hemispheres,and exept they have periods of 4 months,quasi half year,quasi year,4-5 years and 10 years commonly,and each of them has its own respective variation as well.The sea ice area is decreasing apparently since 1980's,so is the polar vortex area,but their abrupt changge time are different totally.The area of sea ice and polar vortex has prominent positive correlation,but the relationship of sea ice intensity,polar vortex intensity,polar vortex area is complicated.  相似文献   

19.
The ability of cell to modulate the fluidity of plasma membrane was crucial to the survival of microorganism at low temperature. Plasma membrane proteins, fatty acids and carotenoids profiles of Antarctic psychrophilc yeast Rhodotorula sp. NJ298 were investigated at -3 ℃, 0 ℃ and 8 ℃. The results showed that plasma membrane protein content was greater at -3 ℃ than that at 8 ℃, and a unique membrane polypeptide composition with an apparent molecular mass of 94.7 kDa was newly synthesized with SDS-PAGE analysis; GC analysis showed that the main changes of fatty acids were the percentage of unsaturated fatty acids (C18∶ 1 and C18∶ 2) and shorter chain saturated fatty acid (C10∶ 0) increased along with the decrease of the culture temperature from 8 ℃ to -3 ℃; HPLC analysis indicated that astaxanthin was the major functional carotenoids of the plasma membrane, percentage of which increased from 54.6±1.5% at 8 ℃ to 81.9±2.1% at -3 ℃. However the fluidity of plasma membrane which was determined by measuring fluorescence anisotropy was similar at -3 ℃, 0 ℃ and 8 ℃. Hence these changes in plasma membrane's characteristics were involved in the cellular cold-adaptation by which NJ298 could maintain normal plasma membrane fluidity at near-freezing temperature.  相似文献   

20.
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