用于形状误差检查的光电传感器

几种工作方式各不相同的非接触式光学测量系统,目前正在座标测量机上进行试验。以自动对焦系统为基础的光电传感器也曾用于测量表面粗糙度。本文将对此种传感器用作圆度检查的实验情况提出报告。在记录圆度偏差的记录曲线上证实了光学传感器与常用的传感器的测量信号不一致。

深孔渐速膛线测量新方法

本文介绍了深孔膛线的测量方法及其测量仪器的改制与误差分析。对光学量仪的综合开发与利用及专用量仪的设计提供了例证。

发动机曲轴加工的质量监控模式

轿车是商品化程度很高的一种工业产品，为应对激烈的市场竞争和迎合众多消费者日益个性化的需求，越来越多的企业正在执行多品种的产品战略，这在当今汽车行业成为一种普遍趋势。在这种行业背景下，作为汽车中最重要的发动机总成，其生产车间现场的质量监控模式随着制造工艺的演变也发生了很大的变化。

Evaluation of an interferometric distance meter

This paper discussed the main parameters contributing to the measurement uncertainty of interferometric distance meter （IDM）. A simple and robust set-up is used to measure distance of about 12 cm with an expanded uncertainty （ k = 2） of ±16.4 μm. The measurement uncertainty is found to be limited by the wavelength measurement accuracy. This set-up can be used to measure distances up to 56 m. It also enables easy determination of the point of equal path difference between the measuring and the reference arms. LabVIEW program is used for counting of the fringes and applying fast Fourier transfor- mation （FFT） to perform frequency selective filtration to the noise. Although the reported uncertainty does not represent the state-of-art uncertainty reached for similar distance, the measurement provides traceable measurement to the unit of length, the meter.

Studies on the Authenticity of Local Wines by Spectroscopic and Chemometric Analysis

The authenticity of 91 wines produced in Cyprus from both indigenous and other vine varieties were investigated by a holistic approach, using, advanced technology such as SNIF-NMR （site-specific natural isotopic fractionation-nuclear magnetic resonance） and 1R-MS （isotope ratio-mass spectrometry） for the determination of the stable isotopes and ICP （inductively coupled plasma spectroscopy） for some heavy metals. The spectroscopic characteristics were evaluated statistically using different chemometric methods. The dependency of the D/H （deuterium/hydrogen） ratio of the methylene site in the ethanol molecule （D/H）ll and also theδ ^18O values of the wine water, were the most useful discriminators. Isotopic results allow us to have a complete idea about the regional variability of the isotopes. Among the metals, Ni followed by Pb was the ones with the highest discrimination value. The determined concentrations of Pb, Ni, Cr and Cd that are related to the safety of wines were within the acceptable limits that have been established by the OIV （international organization of vine and wine） or comparable with the results of the wines of other European countries. The study of the correlation between the load of heavy metals and isotopes in wines showed a dependence on the grape variety but not the geographical location of the vineyard. This is probably due to the close proximity of wine regions in Cyprus.

Dune dynamics in the southern edge of Dunhuang Oasis and implications for the oasis protection

The survival of Dunhuang Oasis is largely determined by the evolution of sand dunes in the southern edge of the oasis, mainly composed of shield dunes and mega pyramid dunes, which occupy twothirds and one-third of the area, respectively. However, few studies have focused on dynamics of these dunes, especially in terms of quantification. So the theoretical basis of sand-control engineering is relatively limited. Here we present the characteristics of dune dynamics of a shield dune and mega pyramid dune in the southern edge of Dunhuang Oasis during April 2014-April 2016 based on measurement data of a 3-D laser scanner. Results indicate that the volume of the shield dune decreased during the monitoring period of two years, and the gravity centers of the monitored shield dune moved windward, indicating that sand was transported toward the oasis. Conversely, the dune volume of the mega pyramid dune increased and the gravity center presented no prominent movement, indicating that the megapyramid dune was relatively stable and its migration toward the oasis was not notable. Thus, compared with mega pyramid dunes, shield dunes in the southern edge of Dunhuang Oasis are identified as a more significant sand source endangering the protection of the oasis, and sand-control engineering should mainly focus on these shield dunes.

A novel three-component hybrid-integrated optical accelerometer based on a Mach-Zehnder interferometer with a LiNbO_3 photoelastic waveguide

An investigation of the properties ofa LiNbO3 photoelastic waveguide via the acceleration-induced effect is presented. A novel three-component hybrid-integrated optical accelerometer based on a Mach-Zehnder interferometer with a LiNbO3 photoelastic waveguide has been designed, which is capable of detecting seismic acceleration in high-accuracy seismic exploration. The Mach-Zehnder interferometer was successfully fabricated and a lighting test used to check its quality. The frequency response characteristic of the accelerometer was measured2 The accelerometer with a resonant frequency of 3549 Hz was demonstrated to show good linear frequency responding characteristics in the range of 100-3000 Hz. The accelerometer also shows good stability and consistency. Experimental results indicate that the outputs of the on- and cross-axis are 147 and 21.3 mV, respectively.

Constraining photon mass by energy-dependent gravitational light bending

In the standard model of particle physics, photons are massless particles with a particular dispersion relation. Tests of this claim at different scales are both interesting and important. Experiments in territory labs and several exterritorial tests have put some upper limits on photon mass, e.g., torsion balance experiment in the lab shows that photon mass should be smaller than 1.2 x 10-51g. In this work, this claim is tested at a cosmological scale by looking at strong gravitational lensing data available and an upper limit of 8.71 x 10-39g on photon mass is given. Observations of energy-dependent gravitational lensing with not yet available higher accuracy astrometry instruments may constrain photon mass better.

Simultaneous Force and Temperature Measurement Using Optical Microfiber Asymmetrical Interferometer

A novel optical microfiber asymmetric Fabry-Perot interferometric （MAFPI） sensor is developed for simultaneous measurement of force and temperature. The MAFPI structure is formed by a weak fiber Bragg grating （FBG）, a section of the microfiber, and a cleaved fiber end surface. The narrowband beam reflected from the low-reflectivity FBG and the broadband beam from the Fresnel reflection interfere lead to its unique sensing performance. The force sensing is performed by detecting the bending-loss induced fringe contrast changes, while the Bragg wavelength shift is employed for temperature measurement. Sensitivities of 9.8pm/℃ and 0.025dB/μN were obtained experimentally for temperature and force measurements, respectively.