稳像平台准确测试系统的研究和设计

对稳像平台的准确测试系统的设计和研制进行了探讨,提出了一种新的采用虚拟仪器软件Labview对前端CCD输出的图像数据进行采集和处理的稳像平台准确测试系统方案.结合稳像平台准确测试系统的具体要求阐述了对系统进行设计的理论,并对采用本方案进行实际设计时的具体步骤、参数取值、测量最大范围、误差估计以及软件设计流程给出了具体的设计方法和参数计算公式.     

Concepts and approaches to in situ luminescence dating of Martian sediments

In this paper we present the concept of a robotic instrument for in situ luminescence dating of near-surface sediments on Mars. The scientific objectives and advantages to be gained from the development of such an instrument are described, and the challenges presented by the Mars surface environment to the design and operation of the instrument are outlined.     

光电微损法检测血糖

介绍了一种新型的光电微损法血糖检测技术 ,以此技术为基础研制的血糖仪以TI公司新推出的低功耗微处理器MSP4 30F4 13为核心。该仪器有 3个特点 :(1)在光电接受部分采用了类似分光计的单波长双检测管结构 ,以避免因发光二极管LED工作状态不稳定而带来的误差 ;(2 )通过多次比较法自动判断反应终止时间 ,即开始计算处理的时间 ;(3)可存储 5 0次测量结果。将其测量血糖浓度的结果与Prestige公司血糖仪的测量结果进行了对比。数据表明 ,其测量结果是准确可信的。光电式微损血糖仪具有操作简便 ,测定时间短 ,结果准确可靠 ,对器件一致性要求不高 ,低功耗等优点 ,是一种供糖尿病患者在家庭中监测控制自身血糖浓度的理想仪器。     

超光滑表面无损检测轮廓仪

本文所述的超光滑表面无损检测轮廓仪,无需标准参考面;利用双焦干涉作非接触无损检测;利用干涉及电子共模抑制技术可有效地抑制各类噪音;计算机控制测量,即时给出表面粗糙度参数,与WYKO比对,结果吻合。仪器特别适合于均方根值R_q为纳米及亚纳米量级的软质金属材料及膜层表面测试。其横向分辨率为1μm,纵向分辨率为0.1nm。     

从显微镜看现代仪器的设计新理念

从现代显微镜这一典型光学仪器出发,分析和阐述了现代仪器的设计新理念。提出了整体式设计、自由曲面式造型设计、人性化设计、绿色设计以及模块化设计等设计新理念。根据显微镜的发展趋势,对现代仪器的发展方向和趋势作了一个预测。     

Two-beam interferometer for optical constants measurements at near-millimeter wavelengths

A simple and versatile instrument for the measurement of optical constants in the near millimeter spectral region is described. Studies of quasi-optical components used in this instrument for effective beam transmission and control are reported. These studies include transmission characteristics of dielectric waveguides and performance of a variable coupler based on frustrated total internal reflection. Operation of this instrument as a two-beam interferometer for determining the index of refraction or as a device to measure transmission for determining the absorption coefficient are described. Values measured with this instrument at 245 GHz, using an optically pumped molecular laser as the source, are reported for several low-loss materials. Appropriate corrections and error estimates are discussed. The potential for improvement and increased accuracies are discussed.Work supported by the U. S. Army Research Office under Grant DAAG29-80-G-0005 and by the NASA Langley Research Center under Grant NAG-1-187.     

微光综合测试仪

分析GJB851-90《夜视仪通用规范》规定的测试方法及所使用的仪器,指出了这种测试方法所存在的缺陷。从测试仪器通用化观点出发,对所使用的观测仪器作了分解和简化,对测试方法也作了改进。以此为基础,讨论微光综合测试仪系列,并对测仪器的主要部件作详细的说明。     

面向近红外光谱定量分析的深度学习建模与模型迁移

近红外光谱分析技术依赖于表征光谱向量和预测目标之间关系的化学计量学方法。然而，样品的光谱由信号和各种噪声组成，传统化学计量学方法较难直接提取光谱的有效特征，并为复杂的预测任务建立具有较强泛用性的校正模型。进一步地，受限于仪器间的差异，在一台仪器上建立的模型应用于另一台仪器时，难以取得相同的定量分析结果。为此，提出了一种基于卷积神经网络和迁移学习的定量分析建模及模型传递方案，以提高模型在单仪器和跨仪器上的预测性能。在卷积神经网络的基础上，一种结合多尺度特征融合和残差结构，名为MSRCNN的先进模型被设计，并在主仪器上展现了卓越的预测能力。然后，设计了四种的基于fine-tune模型迁移策略，将在主仪器上建立的MSRCNN模型迁移到从仪器。在药品和小麦的公开数据集上的实验结果表明，MSRCNN在主仪器上的RMSE和R2分别为2.587，0.981和0.309，0.977，优于PLS，SVM和CNN。在利用30个从仪器的样本微调主仪器建立的模型后，迁移MSRCNN中的卷积层和全连接层的方案取得了最好效果，其RMSE和R2可分别达到2.289，0.982和0.379，0.965。增加参与模型微调的从仪器样本，可进一步提高性能。     

透射式跑道能见度激光测量仪的研究

介绍了一种利用激光测量跑道水平及斜视能见度的智能化仪器。该仪器主要由光学系统、信号放大与处理系统及显示系统三部分组成。简要介绍了该仪器的基本结构、工作原理和主要技术指标，讨论了其中的技术难点及其相应的解决办法。     

基于iOS的手机虚拟仪器浏览器的设计

为了动态调整手机端虚拟仪器的功能,提出了一种基于iOS平台的手机虚拟仪器浏览器的设计方法。其主要原理是通过往浏览器中加载不同的虚拟仪器脚本,将浏览器变成不同的虚拟仪器。虚拟仪器的基本组成模块是拥有多个输入和输出接口的控件,控件之间采用KVO模式进行组装和通讯,并采用脚本描述组装。所有控件类都继承自UIView类,需要调用和重写UIView的部分函数。信号发生显示器的例子证明了虚拟仪器浏览器的可行性。     

Environmental application of pulsed laser-induced incandescence

A portable instrument based on two-color laser-induced incandescence (LII) technique has been designed and developed for the detection of carbonaceous particles for environmental applications. The instrument has been calibrated by performing LII measurements at the exhaust of a home-made soot generator. The incandescence signal from particles sampled into the instrument has been compared with in situ, calibrated, LII measurements to correlate the incandescence signal by the instrument with particles concentration. Measurements of particulate with the LII instrument were then conducted in different environmental conditions, covering a wide range of concentration (from ambient air to cars’ exhaust). The detection limit of the LII instrument has been estimated to be in the range of 200 ng/m³. These measurements have been also compared with results obtained with a commercial aethalometer. The results show a linear relationship between the two sets of measurements, also in the case where significant variation of the carbon particles concentration has been observed over time. These observations allow us to infer that the two instruments are responding in the same way to different carbon particles load, size and nature.     

光的干涉衍射综合实验仪

根据传统的光的干涉衍射实验装置存在的不足,研制出了光的干涉衍射综合实验仪．将光学元件放置在同一小型光学平台上,按照实验需要组合成相应仪器．该实验仪既可以用于光学演示实验,也可以作为光学专用的实验仪器。     

Evaluation of the utility of handheld XRF in meteoritics

We tested a handheld X‐ray fluorescence instrument with adaptable matrix correction for its suitability in meteoritics. We report here the instrument setup, precision and accuracy and present examples of applications. With a measuring time of 300 s, it is possible to collect accurate data for K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Sr and Ba that are needed for the identification of doubtful meteorites and the nondestructive classification of chondrites and achondrites. The factory‐supplied calibration curve of the instrument was fine tuned for our purposes with the use of well‐analyzed meteorite powders, pressed pellets and meteorite hand specimens as standards. Relative errors of 10% to 20% are reached for the mentioned elements. The instrument was tested in the hot desert of Oman while searching for meteorites and also in the laboratory while doing research on meteorites. The main applications of the instrument are the identification and classification of meteorites, the quantification of terrestrial elemental contamination (Sr and Ba) and detection of Mn‐rich desert varnish. It is possible to discriminate the major meteorite groups using Fe/Mn and Ni values. Handheld X‐ray fluorescence is also useful in identifying meteorites belonging to the same fall event. Copyright © 2011 John Wiley & Sons, Ltd.     

Fundamental aspects of pulse phase-locked loop technology-based methods for measurement of ultrasonic velocity.

A new instrument based on a constant frequency pulse phase-locked loop concept has been developed to accurately measure the ultrasonic phase velocity in condensed matter. Measurements of the sound velocity in ultrapure water are reported in which both damped and undamped transducers are used with the instrument together with reflectors of various thicknesses placed in the sound propagation path. An analysis of measurements made with the new instrument and similar measurements, taken under identical experimental conditions, using a popular variable frequency pulsed-phase-locked loop instrument is reported. Uncertainties in both measurement systems are analyzed and discussed. A method for measuring inherent phase shifts, not addressed by previous investigators, within the variable frequency pulsed phase-locked loop system and a derivation of the equations that govern the overall use of variable frequency systems using phase-sensitive comparisons are presented. The effects of a finite pulse length on the measurements of phase velocity in dispersive media are addressed in detail.     

Instrument function of a broadband acoustic thermometric detector

The instrument function of a broadband (1.6–2.5 MHz) detector that is used in acoustic thermometry has been calculated. Experimental tests have proved that measured and computed results are in agreement. The effect of the pass band characteristics and the detector’s dimension on the instrument function has been studied as well as the effect that the instrument function has on an acoustic thermometric signal that is measured by the detector. The ratio of the wavelength (for the mean reception frequency) to the detector’s radius has been shown to be the main parameter that determines the acoustic thermometric signal at distances that are typical of acoustic thermometry. For problems of localizing a heated domain, it is optimal to locate the receiver at a distance of 15–25 mm from the domain. For example, for a detector 8 mm in diameter, the width of the instrument function at a level of 0.5 of the maximum is 1.2 ± 0.1 mm in this zone.     

A sensitivity study on spectroscopic parameter accuracies for a mm/sub-mm limb sounder instrument

The purpose of this paper is to perform a detailed error analysis for a mm/sub-mm limb sounding instrument with respect to spectroscopic parameters. This is done in order to give some insight into the most crucial spectroscopic parameters and to work out a list of recommendations for measurements that would yield the largest possible benefit for an accurate retrieval. The investigations cover a variety of spectroscopic line parameters, such as line intensity, line position, air and self broadening parameters and their temperature exponents, and pressure shift. The retrieval process is performed with the optimal estimation method (OEM). The OEM allows one to perform an assessment of the total statistical error, as well as of the model parameter error, such as the error coming from spectroscopic parameters. The instrument parameters assumed are those of the MASTER instrument studied by the European Space Agency, one of the candidate instruments for a future atmospheric chemistry mission. However, the same principle and method of analysis can be applied to any other millimeter/sub-millimeter limb sounding instrument, for instance the Japanese instrument JEM/SMILES, the Swedish instrument Odin, and the Earth Observing System Microwave Limb Sounder. We find that an uncertainty in the intensity of the strong lines give an error of similar magnitude on the retrieved species to which the lines belong. Uncertainties in the line position have overall a small impact on the retrieval, indicating that the line positions are known with sufficient accuracy. The air broadening parameters and their temperature exponents of a few strong lines dominate the error budget. On the other hand, the self broadening parameters and the pressure shifts are found to have a rather small impact on the retrieval.     

Acoustic cavitation series: part six. Gas body activation

An ultrasonic instrument for the accurate measurement of bolt stress is described. The instrument, which is based on the pseudo-continuous-wave technique, uses carrier phase detection to track the frequency of the mechanical resonance of the bolt. The basic operation of the instrument and the experimental results obtained are discussed.     

负载弦之演示教具

介绍一自制的负载弦教具，5颗沿铀向充磁的圆柱状钐钴磁铁穿在细钓鱼线上，作为负载弦之负载质点，再以可调频率的交流电磁化马蹄形电磁铁，使得马蹄形电磁铁对圆柱状钐钴磁铁施与周期性的引力及斥力，启动负载弦的各个简正模式．此自制的负载弦教具可定量演示教科书中理论计算的结果．     

A high sampling rate digital holographic imager instrument for the in situ measurements of hydrometeors

A novel digital in-line holographic imaging instrument designed for acquiring properties of individual hydrometeors in situ is presented. The instrument has a large measurement volume of 670 cm³. This combined with fast frame rate imaging and software controlled multi-exposure capabilities results in a representative sampling of rain and snowfall events. Hydrometeors are measured and analyzed from the in-focus images with microscopic resolution, and their 3D locations inside the measurement volume are determined. The instrument is designed to operate in cold climates and to produce reliable measurements also during strong winds. The imaging rate of the instrument was designed to be adequately high to observe the dynamic nature of rain and snow falls. By recording multi-exposure holograms, the effective frame rate can be increased. This allows the measurements of the velocities of the fast-falling hydrometeors. The instrument and the hologram processing are described; as well as results from laboratory tests and the first field measurements are shown. As a result, the resolving power of the instrument was measured to vary between 11 and 18 microns inside the measurement volume near the center of the field-of-view. Velocity vectors were measured both from multi-exposure and high frame rate holograms. The measured velocities ranged from 0.1 to 4 m/s. In addition, the projections of a flat-shaped and rotating snowflake imaged at different locations inside the measurement volume demonstrated the possibility to estimate the shape of the hydrometeor from multiple viewing angles.     

双激光光源光吸收法甲烷浓度光纤监测仪

基于Lamber Beer定律,利用波长为1.33μm的脉冲InP/InGaAsP半导体激光器作为测量光源,用低损耗的光纤进行光信号的传输,并以钽酸锂热释电探测器作为光电转换器件,实现了一种可远距离监测甲烷浓度的仪器。该仪器主要由光纤传感系统、信号放大与处理系统和显示系统三部分组成。介绍了该仪器的基本结构与工作原理,讨论了其中的技术难点及其相应的解决方法。