基于LabVIEW的砝码自动检定系统设计与实现

针对目前砝码检定工作操作过程复杂、检定效率低等问题,设计了一种基于LabVIEW的砝码自动检定系统。在符合砝码检定规程的情况下,系统实现了检定数据实时采集、数据处理、生成原始记录、管理标准器、查询历史数据和衡器控制等功能。相对现有的砝码检定方法有操作简单、高效、程序移植性好等优点。系统由主控计算机、串口转无线扩展卡、多台衡器设备及相应的标准砝码装置组成。通过使用串口转Wi-Fi模块,系统可实现控制多台衡器设备的需求。实验结果证明,系统运行稳定可靠,采集数据准确,容易扩展,且大幅度减轻了检定人员的劳动强度,在计量检定工作中具有一定的实用和推广价值。     

多光谱多光轴自动校准技术

分析了具有红外、电视和激光的光电仪器进行多光谱多光轴自动校准的方法.指出在武器系统的设计中,如果条件允许,可在光电仪器的后方设置一个校准棱镜箱(或折反式自准凹面镜组件),以便在控制电路中加入电十字线跟踪产生器等功能单元,使武器系统实现行进间或飞行中自动校准.     

基于PXI总线的多路机上铂电阻温度校准系统的设计

针对旋钮式铂电阻模拟仪在温度校准中单次单通道效率低下的问题,提出一种基于PXI总线的可编程多路铂电阻温度校准系统。对系统功能、硬件组成、工作原理和软件设计做了详细的论述。多路温度校准系统选用基于PXI总线的可编程电阻卡,通过程序指令设定温度校准点,经由以太网进行数据传输,上位机软件进行数据记录和处理,最终实现了机上多通道的温度自动化校准。该设备已应用于型号试飞工作中,显著地提高了校准效率和可靠性。     

Study on measurement technology of ultra-low brightness北大核心CSCD

光亮度是表征发光体的重要光度特性参数。提出了一种超低亮度计的设计方法,描述了超低亮度计的工作原理和组成;利用微弱光信号处理技术、非线性校准技术、制冷散热技术等实现了超低亮度的自动测量;根据亮度计的测量原理,对仪器进行了标定,测量不确定度达到5%。超低亮度计可适用于实验室和现场等测试场所,为微光夜视装备、显示系统、特种光源、发光材料等的性能评估测试和校准提供计量保障。     

静电计检定标准装置的建立

静电计是直接用于测量微小电流、电压和电荷（有的还具有测高阻的功能）的仪器，进V1或国产的不同类型、不同级别的静电计使用广泛。目前没有直接校准／检定静电计的计量标准，过去是靠现有的有关计量标准进行间接校准／检定，不确定度较大，只能开展不确定度为10^-2的静电计校准／检定工作，不能满足计量传递要求。静电计检定标准装置的建立，解决了静电计的量值传递问题。     

亮度式测温仪自动瞄准系统设计

亮度式测温仪的校准大多采用人工方式,人为影响因素较大且校准重复性较低.为了使测温仪在校准时能够准确自动地瞄准温度灯的瞄准点,采用YG-QP36四象限探测器,设计出双自由度自动瞄准系统的机械运动结构,利用步进电机的自锁和双向精确定位特性,双自由度扫描温度灯的瞄准点.用光纤将电子元器件与高温环境隔离开,减少温度对电子元器件的影响.在800~1 200℃温度范围内采集测温仪的温度-电压数据,并用最小二乘支持向量机进行拟合,测量数据的相对误差小于0.05%,重构均方差为0.019 6.对光斑圆心到坐标原点的距离与电压进行最小二乘拟合,光斑直径测量数据表明,双自由度自动瞄准系统能够提高校准准确度,减小重复校准误差.     

一种自校准光纤珐珀动态应变检测系统的实验研究

针对工程中光纤珐珀传感器的工作点容易偏离线性工作区而使解调系统无法正常工作的实际问题,设计了一种可实现自动校准工作点的动态应变检测系统。该系统利用数字信号处理器控制可调珐珀滤波器自动输出波长满足工作点要求的窄带光,同时还通过软件校准的办法消除了因光源的不稳定、系统老化等缓变因素引起的信号波动对测量结果的影响。实验结果表明该动态应变检测系统能完成工作点自动校准,并且在500με范围内线性度可达99．79％,实验分辨率约为±0．5με。     

基于C Sharp的激光位移传感器校准装置测控软件设计

针对高精度激光位移传感器校准的需求,基于C Sharp设计了激光位移传感器自动校准装置测控软件,实现了对位移的测量、数据采集、数据处理、数据保存并显示结果等功能;测控软件对硬件设备的通信与控制采用了面向对象的编程思路,例如针对激光干涉仪、直线位移平台、数字多用表等设备,设计了相应的类,提高了软件的可拓展性,同时也便于系统硬件的升级;数据处理采用多种线性拟合算法计算激光位移传感器的线性度,满足不同情况下的参考需求;实验结果表明,测控软件系统运行稳定,数据的自动采集处理方便快捷,减小人工处理数据引入的误差,提高了激光位移传感器校准的准确性和效率。     

基于实时双光路校正的分光测色仪优化设计

设计了一种基于实时双光路校准的分光测色仪结构,在现有双光路设计中加入校准光源对主光路和辅助光路进行实时双光路校准.构建算法对由温度变化引起的传感器响应效率变化进行修正,并设计实验在不同温度下对仪器采样稳定性进行评价.实验表明,采用了实时双光路校正仪器的工作温度从10℃变化至30℃后,测量数据稳定性标准偏差小于等于0.03,最大偏差小于等于0.04,相对于现有技术方案有显著改善.     

小型轻便式流速仪检定系统设计

为满足FP系列流速仪的计量检定需求,提出了一种小型便携式流速仪检定系统的设计方案。根据匀速运动时间等约束条件确定了环形水槽的几何参数。采用FPGA和上位机作为数据处理和控制核心,实现了对伺服电机转速的精确控制。设计了光电编码器和无线摄像机与上位机之间的通信方式,实现了检定装置标准流速值和被检仪器示值的数据读取。对测试数据的处理方法和测控软件的结构框架进行了分析。同时,对实验装置的测量误差进行了分析。结果表明,标准流速值的扩展不确定度为1.28×10-3m/s,检定装置符合量值传递要求,可作为FP系列流速仪计量检定的标准装置。     

白光和红绿蓝光LED可调光源研制

为了提高LED光源色温和亮度的调节精度和准确度,结合色温由低向高变化时光色所呈现的渐变特点,提出了一种低色温白光LED灯珠、高色温白光LED灯珠加红绿蓝光LED灯珠补偿式调光的方法.将色温分成三个部分进行调节,每个部分选用不同的LED灯珠组合来进行调光.实验结果表明:不同组合情况下的LED光源的初始输出色温相对于目标值的偏差范围在1％以内;亮度可以在保证色温不变的情况下独立进行调节,初始输出值与目标值的偏差范围在1％以内;经过微调之后可以达到目标值;达到了色温和亮度独立调节的要求;光源发光稳定,不会因为长时间工作而影响调节精度.     

Muonic and pionic L- and M-series in carbon and oxygen and the pionic 2p level shift and width of oxygen

Muonic and pionic X-rays of the L- and M-series in C and O have been measured with a Si(Li) detector in the energy range between 7 keV and 60 keV. The target consisted of mylar (C₅H₄O₂). Energies and intensities of 21 transitions have been determined. The strong interaction shift of the pionic 2p level in O was measured and found to be +4.1 ±2.3 eV. The measured width of this level is 11±6 eV. The measured yields have been compared with cascade calculations.     

Visualization and interferometry for cylindrical and spherical sample tomography and profilometry

A technique combining image processing and laser interferometry for visualizing and detecting the deformation of transparent cylindrical and spherical sample is proposed. This deformation includes geometric deformation such as volume transition in profilometry and physical deformation such as refractive index change in tomography. Phase contour lines are used for quantitative analysis and graphical representation of the deformation. This method allows us to visually detect the spatial variation of the deformation field and to evaluate the test quality such as misalignment of optical system. A theoretical analysis using phase contour map to characterize the deformation field is described in detail. A method using phase contour map to qualify the interferometric test is proposed. Analysis of test examples is carried out. Suggestions on using phase contour line method to ameliorate test system design are finally discussed.     

Nonlocal potentials and their exact and approximate local and velocity-dependent equivalents

We show that good approximations to the exact equivalent local potential (ELP) and damping factor of a nonlocal Perey-Buck potential can be calculated in the partial wave WKB approximation of Horiuchi. The exact ELP and damping factor are obtained by means of a method previously given by one of us. We also confirm that an approximate ELP proposed by Bauhoff et al. is of comparable accuracy as the Horiuchi approximation. Thesel-dependent ELP's exhibit reduced attraction in the interior and provide a test for higher order WKB approximations. We subsequently obtain an equivalent velocity dependent potential (EVDP) which is even exactly wave function equivalent to the original nonlocal potential. This almost local potential, unlike the trivial equivalent local potential, is smooth and well-behaved and is therefore particularly useful in nuclear reactions where the off-shell behaviour of the potential is important.     

Quantum and Classical Disparity and Accord

Discrepancies and accords between quantum (QM) and classical mechanics (CM) related to expectation values and periods are generally found for both the harmonic oscillator (SHO) and a free particle in a box (FPB), which may apply generally. These indicate non-locality is expected throughout QM. The FPB energy states violate the Correspondence Principle. Previously unexpected accords are found and proven that 〈x ²〉 _CM =〈x ²〉 _QM and τ _CM =τ _QMb (beat period i.e. beats between the phases for adjoining energy states) for the SHO for all quantum numbers, n. However, for the FPB the beat periods differ at small n. It is shown that a particle’s velocity in an infinite square well varies, no matter how wide the box, nor how far the particle is from the walls. The quantum free particle variances share an indirect commonality with the Aharonov-Bohm and Aharonov-Casher effects in that there is a quantum action in the absence of a force. The concept of an “Expectation Value over a Partial Well Width” is introduced. This paper raises the question as to whether these inconsistencies are undetectable, or can be empirically ascertained. These inherent variances may need to be fixed, or nature is manifestly more non-classical than expected.     

Spin and Statistics and First Principles

It was shown in the early seventies that, in Local Quantum Theory (that is the most general formulation of Quantum Field Theory, if we leave out only the unknown scenario of Quantum Gravity) the notion of Statistics can be grounded solely on the local observable quantities (without assuming neither the commutation relations nor even the existence of unobservable charged field operators); one finds that only the well known (para)statistics of Bose/Fermi type are allowed by the key principle of local commutativity of observables. In this frame it was possible to formulate and prove the Spin and Statistics Theorem purely on the basis of First Principles.