影响农村居民健康的社会经济因素分析

如何度量影响健康的社会经济因素是一个困难的问题,不同于以往文献直接沿用国外文献中的做法,而是从我国农村现状出发,从个人和家庭社会关系两个层面入手选择社会经济因素的度量指标.基于CHIP2013大型微观数据集,定量分析了影响我国农村居民健康的社会经济因素,研究结果对影响农村居民健康的社会经济因素提供了更具时效性、更全面的认识.研究发现,个人层面的身份地位、职业选择、教育程度以及家庭层面的家庭经济条件和家庭社会关系对个人健康有正向影响.基于对这些社会经济影响因素的分析,提出了促进农村居民健康的一些政策启示,包括提升农村教育水平,增加农村家庭经济收入、增加非农就业机会以及建立全面的农村医疗保障制度,以提高农村居民抗击疾病风险的能力.     

Chemical metrology in New Zealand

Recent developments in international trade will have a significant impact on New Zealand’s measurement infrastructure, especially for chemical metrology. This article describes the background to these developments and outlines the activities of the Measurement Standards Laboratory, New Zealand’s National Metrology Institute, in response to these developments.     

Towards quantum-enhanced precision measurements： Promise and challenges

Quantum metrology holds the promise of improving the measurement precision beyond the limit of classical approaches.To achieve such enhancement in performance requires the development of quantum estimation theories as well as novel experimental techniques.In this article,we provide a brief review of some recent results in the field of quantum metrology.We emphasize that the unambiguous demonstration of the quantum-enhanced precision needs a careful analysis of the resources involved.In particular,the implementation of quantum metrology in practice requires us to take into account the experimental imperfections included,for example,particle loss and dephasing noise.For a detailed introduction to the experimental demonstrations of quantum metrology,we refer the reader to another article’Quantum metrology’in the same issue.     

Inspection of nano-sized SNOM-tips by optical far-field evaluation

High resolution optical microscopy has many interesting applications in solid state physics, low temperature physics, biology and semiconductor technology. Unfortunately, the lateral resolution of conventional microscopes is limited by the Rayleigh-limit. “Scanning nearfield optical microscopy” (SNOM) seems to be a promising new approach to characterize the properties of materials optically with a high lateral resolution of 50–100 nm. The most important part of such a microscope is the scanning probe (a special glass fiber tip). However, the quality of the optical fiber tip is of decisive importance. Since the production process of pulled and coated glass fiber tips is still highly empirical and error-prone, a technique would be useful to determine the tips’ quality before they are shipped to the user or mounted in the microscope. The tips’ apertures are smaller than λ/2 and therefore they cannot be measured in a non-destructive way by conventional optical microscopy. This paper discusses an easy and fast method for the optical characterization of common glass fiber SNOM tips. The effective aperture of the tip is measured from the far-field distribution of the emitted intensity recorded by a CCD target. A numerical model is introduced to solve this inverse task and a simple optical setup is presented to detect light emitted by the tip at an angle of up to 90° from the optical axis. Experimental investigation, near/far-field calculations and scanning electron microscope investigations show the working principle of this measurement technique for the analysis and evaluation of a typical nanostructured object.     

Optical Metrology by Fringe Processing on Independent Windows Using a Genetic Algorithm

We present a method to retrieve the phase of a fringe pattern based on the window fringe pattern demodulation technique (WFPD). The overlapped phase similarity criterion is avoided in the proposed method, and it is substituted by a second order smoothness criterion. The fringe processing on independent windows (FPIW) method can measure physical quantities from closed and near sub-sampled fringe patterns by a simplified cost or fitness function. The fringe image is divided into a set of partially overlapping windows. In these sub-images the estimated phase is modelled as a parametric analytic-function, and its parameters are optimized using a genetic algorithm (GA). This analytic-function is used to estimate the phase in the area framed by the window. Phases from all windows are sequentially spliced to retrieve the whole phase field. A media filter is applied over the entire phase field to smooth the irregularities that appear in the junctures between windows.     

热释电双波长光纤测温仪的精度分析

在介绍一种利用钽酸锂热释电探测器实现的实用化双波长光纤测温仪的基础上,着重讨论了反射辐射、探测器周围环境的热辐射、仪器工作波长的带宽,以及光路中选择性吸收气体的光谱吸收等多种因素对仪器测温精度的影响,并提出了相应的抑制措施。实验表明,采取相应的抗干扰措施后,在系统要求的测温范围400—1360℃内,其测温精度符合设计要求。     

Inverse projected-fringe technique based on multi projectors

The inverse projected-fringe technique based on multi projectors is proposed. By an absolute phase measurement on the master object, different inverse fringes are generated, for projectors placed in different directions. During the inspection process, inverse fringes are projected simultaneously. If the test object and the master object are identical, an optimized sine fringe is obtained on the camera. Otherwise, every faulty area of the test object causes distortions of the fringe. The deformations can be evaluated quantitatively by simple Fourier transformation and phase unwrapping. Therefore, we can complete the inspection of complex and discontinuous objects with only one fringe image, and solve the problems of shadow and break to a large extent, and consequently realize the fast on-line inspection. The principle of this technique is expatiated, and we prove the validity of it on the example of a two-projector system. The analysis of error and prerequisites of application are also presented.     

城市化进程中外来民工居住问题研究

外来民工的居住问题是影响城市化、外来民工市民化的一大阻碍．住宅业和城市化关系密切，相互促进．现阶段，住宅业的发展不适应城市化以及外来民工市民化的要求．城市化将给住宅业带来巨大的发展空间，同时也给住宅业的发展提出了更高的要求．住宅业要为城市化服务，积极配合城市化的发展．     

飞秒光梳和碘稳频532nm Nd:YAG激光频率的测量

报道了中国计量科学研究院研制的基于掺钛蓝宝石(Ti:Sapphire)锁模飞秒脉冲激光器的飞秒光学频率梳装置，并利用此装置测量了碘稳频532nm(¹²⁷I₂R(56)32-10) Nd∶YAG固体激光器的频率，结果为 563260223512991±20Hz,相对不确定度为3.6×10^-14.这一数值是直接溯源到铯原子微波频率基准的光学频率测量结果.