Numerical reconstruction of one-photon mixed states by means of the degree of linear polarisation

In this paper the authors present the idea for reconstructing one-photon states. Reconstructing a quantum state means measuring the probability distribution P that allows one to write the density operator for the analysed state. The most commonly known approach for the quantum reconstruction is the quantum tomography. Our alternative method assumes that the analysed field is coupled with the reference field which is described by the parameters settled during a measurement. In the proposed gedankenexperiment the degree of linear polarisation (DOLP) of this combined beam is measured using a rotating linear polariser. We state that it is possible to obtain the P-function by changing the parameters of reference beams and by preparing the series of DOLP measurements. This series of data leads to the system of equations. The values of the P-function at chosen points are the unknowns of this system. This article focuses on the numerical algorithm for solving these equations.     

空气比释动能率测量不确定度评定

文章主要论述工业X射线探伤机空气比释动能率测量不确定度的评定，并详细分析了空气比释动能率不确定度的来源、标准不确定度分量的评定及自由度的计算等。     

A generalized approach to the reconstruction of a restricted class of digitized planar curves

Reconstruction of an original continuous curve and the estimation of its parameters from the digitized version of the curve is a challenging problem, as quantization always causes some loss of information. In this paper, we have developed a scheme for reconstruction which is applicable to a class of curves having at the most two parameters. The class of curves for which the scheme works has also been characterized. We have shown that for one-parameter curves the exact domain of values of the parameter can be obtained. But in the two-parameter case, only the smallest rectangle containing the domain can be realised. The distinctive feature of our scheme is that it provides a unified approach to solve the reconstruction and the domain-finding problem for a class of curves.     

双波长激光量块干涉仪减小量块中心长度测量不确定度的措施

该文总结了双波长激光干涉仪研制过程中减小量块中心长度测量不确定度的几项重要措施,该干涉仪对量块中心长度的测量不确定度达到(0.02±0.2L)μm,并已成功应用于高等级量块的自动测量。     

Proposal for measuring the quantum states of neutrons in the gravitational field with a CCD-based pixel sensor

An experimental setup is proposed for the precise measurement of the quantum states of ultracold neutrons bound in the earth's gravitational field. The experiment utilizes a CCD-based pixel sensor and magnification system to observe the fine structure of the neutron distribution. In this work, we analyzed the sensor's deposited energy measurement capability and found that its spatial resolution was . A magnifying power of two orders of magnitude was realized by using a cylindrical rod as a convex mirror.     

An exact solution approach for disassembly line balancing problem under uncertainty of the task processing times

The purpose of this work is to efficiently design disassembly lines taking into account the uncertainty of task processing times. The main contribution of the paper is the development of a decision tool that allows decision-makers to choose the best disassembly alternative (process), for an End of Life product (EOL), and assign the corresponding disassembly tasks to the workstations of the line under precedence and cycle time constraints. Task times are assumed to be random variables with known normal probability distributions. The case of presence of hazardous parts is studied and cycle time constraints are to be jointly satisfied with at least a certain probability level, or service level, fixed by the decision-maker. An AND/OR graph is used to model the precedence relationships among tasks. The objective is to minimise the line cost composed of the workstation operation costs and additional costs of workstations handling hazardous parts of the EOL product. To deal with task time uncertainties, lower and upper-bounding schemes using second-order cone programming and approximations with convex piecewise linear functions are developed. The applicability of the proposed solution approach is shown by solving to optimality a set of disassembly problem instances (EOL industrial products) from the literature.     

Scheme for implementing 1 → 2 symmetric economical phase-covariant telecloning of bipartite entangled state based on quantum logic network

A scheme for implementing 1 → 2 symmetric economical phase-covariant telecloning of a bipartite entangled state is proposed based on a quantum logic network. The quantum circuits for preparing the telecloning channel and for teleporting the input state are presented, respectively. There is no ancilla needed for preparing the channel, and the fidelity of telecloning is enhanced. Due to only single- and two-qubit operations being used in the whole process, it can be easily implemented in experiment.     

纳氏试剂光度法测定水质氨氮不确定度的评估

通过对纳氏试剂光度法测定水质氨氮过程的分析,对测定不确定度做出评估。得出影响测定结果的几种重要因素。     

测功机转矩示值误差测量结果的不确定度评定

本文主要根据JJF 1059-1999测量不确定度评定与表示计量技术规范，对测功机转矩示值误差的测量结果进行不确定度评定。通过评定，以此作为对相同情况下的测功装置进行测量不确定度评定的一种模式，以便于今后工作的开展。     

Padé approximants applied to the equation of state and heat capacity of quantum ideal gases

Padé approximants have been applied to the equation of state and heat capacity of the quantum ideal gases. For the Bose gas the agreement is almost perfect. For the Fermi gas, the maximum relative error is 0.03% for the former and 0.4% for the latter.     

基于最优参数实现 Lorenz-stenflo系统的相空间重构

摘要：以一个新的扩展 Lorenz系统为背景,利用向量间的相似度改进了相空间重构所需的最优延迟时间的算法,并最终实现了该系统的相空间重构。数值结果表明改进后的算法是有效的,可能更好选择最优延迟时间。     

Methods for evaluating the accuracy characteristics of the range finder channel of quantum optical systems

Methods for estimating the instrument error for quantum-optical systems using active and passive optical measures of length are suggested. One is based on simulation of measured pulses reflected from the object and entering the receiving device; another is based on using a section of the fiber optical path. __________ Translated from Izmeritel’naya Tekhnika, No. 5, pp. 19–22, May, 2006.     

Localizable imaging study for the noninvasive diagnosis of lesions with the backscattering polarized light

The asymmetry appearing in the degree of polarization (DOP) distribution of the backscattering polarized light from tissues is investigated by using polarized Monte Carlo simulation. When the incident point is close to the boundary of the lesion inside the tissue, high asymmetry emerges regardless of the polarized direction of the incident light. A noninvasive method based upon the DOP asymmetry of the backscattering light is proposed to locate lesions hidden in live tissues by scanning a point light source. Imaging of the front projection on complicated lesion structures is demonstrated with this method. Its transverse resolution, which is affected by the wavelength of incident light and the size of the scattering particle, can reach the diameter of the lesion scattering particle theoretically while the best longitudinal detection depth can be achieved by choosing a suitable incident wavelength according to the scattering characters of the tissue.     

温度计修正值不确定度评定方法的改进研究

"JCGM 100:2008"的温度计修正值不确定度评定案例中,模型为bt=y1+y2(t-20),自变量(t-20)与因变量修正值bt=(tR-t)间不独立,实质上选温度计示值t作自变量、标准值tR作因变量,前者的误差影响显著大于后者,这与应选误差影响可忽略的作自变量的原则相悖.案例中评定b(t′)的不确定度ubt′错用了求预测值置信区间的预测模型,应先改用tR作自变量拟合、再求反预测值tR(t′)及其置信区间的校准模型,我们在预测和校准两种情况下计算了ubt′以作比较.案例中limn→∞ubt′=0有逻辑性瑕疵.对自变量等距分布、自变量在区间两端集中各半这两种情形,算出其斜率标准差的期望值之比约槡3,否证了"测散布数据最小二乘拟合主要为减小因变量的独立同分布随机误差影响"的命题,初步导出"主要为减小因变量的具有随机性的未定系差分量影响"的推论,质疑了高斯-马尔科夫假定的普适性.考虑因变量标准差包含两类分量,提出了预测或校准(反预测)模型下的置信区间的调和近似算式.     

Estimation of uncertainty with the modulus of elasticity measured by means of tensile test for BSCCO tapes

The international round robin test (RRT) was conducted in order to establish the international standard for the tensile test method for BSCCO-2223 tape shaped wires. The measurands of mechanical properties were statistically analyzed to estimate their standard uncertainties and their correlation among laboratories. Consequently the large variance was observed with the modulus of elasticity determined from the initial loading curve. The reason has been examined by estimating type B uncertainties causing at every step of the experimental procedure. With respect to the modulus of elasticity, the grand intra-lab average of relative standard uncertainty (RSU) obtained from the RRT coincided roughly with that derived by means of type B evaluation. Thus it is emphasized that the type B evaluation is very effective tool for expecting the uncertainties of the observations like the modulus of elasticity. On the other hand, the grand over-all RSU was larger than the grand intra-lab one. The combined standard uncertainties were calculated by changing the strain rate, but kept other parameters constant. In order to suppress the influence from the strain rate to the variance, it has been recommended that the strain rate shall be regulated less than 2 × 10⁻⁴ 1/s in the tensile test method.     

温度对InAs/GaAs量子点生长影响的动力学蒙特卡罗模拟

采用动力学蒙特卡罗模型模拟了GaAs应变弛豫图形衬底上InAs量子点阵列生长早期阶段,温度对浸润层之上第一层亚单原子层阶段的影响.通过对生长表面形态、岛平均大小、岛大小分布及其标准差等方面的研究,证明了通过控制温度能够得到大小均匀、排列有序的岛阵列,这对后续量子点生长的定位和尺寸控制有重要影响.     

Effect of the bimodal size distribution on the optical properties of self-assembled Ge/Si(001) quantum dots

In situ reflection high-energy electron diffraction, atomic force microscopy and photoluminescence spectroscopy have been combined to investigate the effects of a bimodal size distribution and of the pyramid/dome transition on the optical properties of related Ge/Si layers. It is shown that the wetting layers are inhomogeneous in thickness due to the lateral diffusion of Ge from 2D layers towards islands, while no change is observed in the island-related photoluminescence. These results obtained indicate that 3D islands are, in their early nucleation stages, formed by consuming Ge from 2D layers, and that island luminescence energy is not sensitive to the vertical confinement inside islands.     

分布参数的主观不确定性对结构平均输出性能方差影响的降维分析方法

为了有效控制结构平均输出性能,研究了分布参数主观不确定性对平均输出性能方差的影响.考虑到分布参数的主观不确定性对平均输出性能的方差贡献与分离主、客观不确定性后分布参数的主观不确定性对输出性能的方差贡献相同,并针对传统Monte Carlo方法效率低、计算量大的缺点,首先采用乘法降维方法求解基于平均性能方差的全局灵敏度,该方法对功能函数的调用次数远远小于传统的Monte Carlo方法;其次将主、客观分离方法与乘法降维方法相结合,求解分布参数的主观不确定性对平均输出性能方差的影响,该方法在保证精度的同时,进一步提高了计算效率.