7 research outputs found

    Low Power Consumption、High Stability CMOS Ring Oscillator

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    低成本、低功耗的振荡器已成为市场的主导需求;而高密度的频谱资源对振荡器的精确性和稳定性提出更高要求。因此,频率稳定的振荡器是集成电路设计的热门难点课题。 本项目采用UMC0.6µm线宽工艺,使用内部独立电压源结构,借助差动延时单元的抑制噪声作用,设计一种输出频率为8MHZ、精度为2%的CMOS环形振荡器。就此,本文的研究工作及研究成果如下: 1.根据巴克豪森准则和线性时变噪声模型对振荡器的环路级数、增益,及相位噪声进行模型匹配,得到了能降低相位噪声的振荡环路结构和MOS管尺寸优化的系统设计方案。 2.为解决系统电路模块中的外部电源噪声,将电压提升电路和Bandgap电路在芯片...Low cost, low power consumption oscillator has been the main requirement in the oscillator market, and the limited resource of spectrum call for more stable and accuracy oscillator. So designing a frequency stable oscillator is a hot and hard topic in IC design. This project uses model of UMC 0.6µm to design a stable 8MHZ, 2% precision CMOS ring oscillator, with internal independent power s...学位:工学硕士院系专业:物理与机电工程学院机电工程系_精密仪器及机械学号:20042901

    A Flux Control System Based on Single Chip

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    介绍一种以PIC16F876为核心的流量控制系统,通过单片机与计算机通讯,实现远距离的自动控制,控制系统经使用效果良好。文章给出了系统设计原理、单片机程序流程图和硬件电路。This paper presents a flux control system based on the single chip PIC16F876.The system realizes the long distance auto control by the communication between single chip and computer.The result has been proved to be good.The design principle of the system,flow chart of single chip and the related circuits are introduced in detail

    The Examination Of So_4~(2-) In The Water Sample Of Oil Field By Potential Titration

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    阐述了电位滴定法检测油田水样中的SO42-的原理、实验条件及操作步骤,分析了操作过程中影响准确性的因素,并且根据实验需要设计了一个高阻抗放大器电路,可测试的最低浓度达到1mg/l左右。Expatiate the theory, experiment condition and operation process that examine SO42 in the water sample of oil field by potential titration. Analyze the factor that will affect the veracity in operation process. Design a high-impedance amplifier based on the demand of experiment. The lowest concentration that can be examined is about 1mg/l

    The Principle And Applications Of ADXRS Angular Rate Sensing Gyroscope

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    介绍ADXRS角速度检测陀螺仪的原理和电路结构,具体描述该陀螺仪外围电路的连接方法。为了使用ADXRS角速度陀螺仪测量角度,设计一种对角速度积分的方法,实现对角度的测量。阐述实验过程中硬件和软件的设计过程。实验结果表明:该实验方法能较准确的测量物体旋转的角度。The principle and the block diagram of ADXRS angular rate sensing gyroscope are introduced, and the external circuit of this gyro is described in detail. In order to measure angle with ADXRS gyroscope, a method of angular rate integral is designed. The design of hardware and software in this experiment is expatiated. The result reveals that this method of experiment can measure angle accurately

    面向遥感影像镶嵌的SVR色彩一致性处理/Support vector regression color normalization method for image mosaic[J]

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    由于成像条件与环境的差异,多景待镶嵌遥感影像之间往往会出现色彩差异,针对此问题,提出一种基于支持向量回归(SVR)的色彩一致性处理方法.采用NDVI(归一化植被指数)阈值分割并结合光谱角匹配(SAM)的方法在影像重叠区域自动选取具有“不变特征”的像素作为样本;通过SVR建立输入影像到参考影像的灰度值变换方程,并对输入影像进行处理,使得待镶嵌影像具有与参考影像相同或者相似的亮度与对比度.采用TM、SPOT、无人机(UAV)影像等多源数据进行了实验,结果表明,该方法能够有效消除由系统因素引起的色差,与线性回归方法相比,该算法在方差、辐射分辨率等方面具有优势

    联合概率密度脊提取的影像镶嵌色彩一致性处理方法/Ridge of Joint Probability Density Based Color Normalization Method for Image Mosaic[J]

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    针对大区域待镶嵌遥感影像之间存在亮度分布和对比度不一致的问题,提出一种联合概率密度脊提取的色彩一致性处理方法.统计两景影像重叠区域对应波段亮度值的联合概率密度,并从中提取通过“脊”的直线作为回归方程,对输入影像进行处理,使得影像间具有类似的对比度和亮度分布.选取TM数据进行了试验,结果表明:镶嵌结果色彩均匀、视觉特征良好,与传统方法相比具有较好的稳定性和统计特征

    板坯号自动识别系统的研究与实现/Study and implementation of steel slab ID automatic recognition system[J]

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    手写数字自动识别应用在热轧炼钢生产流水线中可解放劳动力,提升准确率并提高工作效率.为此根据具体需求,系统地分析了板坯号图像获取与处理、数字识别,板坯号规则匹配等自动化过程,重点研究了板坯定位和分层分类识别等关键技术,实现了板坯的自动定位、手写板坯号的自动识别和系统录入.实验结果与实际应用表明,该系统达到了较高的识别正确率,进而集成并实现了板坯号自动识别系统,具有较好的应用效果
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