Phase measurement accuracy of feedback interferometers

Feedback interferometers are described with specific reference to potential applications in micro-machines. A theoretical analysis is developed to determine the linearity, stability, and noise performance of this type of interferometer. The theoretical analysis was tested using a prototype high-precision feedback interferometer which showed that, at a feedback loop gain which enabled the system to track 6 fringes, the linearity of the interferometer was better than λ/100 and single phase measurements could be made with an accuracy of λ/80.     

On the spatial-temporal averaging method for modeling transport in porous media

The spatial-temporal averaging procedure is considered with a nonhomogeneous distribution of elementary domains in the spatial-temporal space and the probabilistic interpretation of the ST-averaging is also given. Several averaging theorems and corollaries about the averages of spatial and temporal derivatives are presented and rigorously proved which allow elementary domain to vary in space and time. The macroscopic transport equation in the most general condition and the simplified macroscopic equation under the special form of distributions are developed which may be reduced to the classical macroscopic transport equation as the spatial-temporal average degenerates into the volume average.     

An asymptotic minimax risk bound for estimation of a linear functional relationship

We consider estimation of the parameter B in a multivariate linear functional relationship X_i=ξ_i+ξ_1i, Y_i=Bξ_i+ξ_2i, i=1,…,n, where the errors (ζ_1i^′, ζ_2i^′) are independent standard normal and (ξ_i, i ) is a sequence of unknown nonrandom vectors (incidental parameters). If there are no substantial a priori restrictions on the infinite sequence of incidental parameters then asymptotically the model is nonparametric but does not fit into common settings presupposing a parameter from a metric function space. A special result of the local asymptotic minimax type for the m.1.e. of B is proved. The accuracy of the normal approximation for the m.l.e. of order n^−1/2 is also established.     

Accurate mass measurement and tandem mass spectrometry of intact globin chains identify the low proportion variant hemoglobin Lepore-Boston-Washington from the blood of a heterozygote

Within a mixture of proteins, minor polymorphic components are difficult to identify using a conventional proteomic approach. Their identification generally requires multi-dimensional separation steps, before or after proteolytic cleavage, followed by sequence analysis of the proteolytic products. In this study, we investigated the potential of tandem mass spectrometry for protein characterization by identifying the delta-beta hybrid human hemoglobin variant Lepore-Boston-Washington using electrospray ionization tandem mass spectrometry. Hemoglobin Lepore-Boston-Washington occurs mainly in heterozygotes, where it comprises approximately 10% of the total non-alpha-chains, the dominant non-alpha-chain being the normal beta (approximately 90%). Furthermore, Hemoglobin Lepore-Boston-Washington has an average molecular mass (15,865.23 Da) that is only 2 Da lower than that of the normal beta-chain (15,867.24 Da). Consequently, it cannot be resolved from the normal beta-chain by mass spectrometry. Here we show how Hemoglobin Lepore-Boston-Washington was identified directly from the diluted blood of a heterozygote by analyzing the product ions from the Lepore-Boston-Washington and normal beta-chain ions without prior separation of the individual chains. This study shows the potential of the tandem mass spectrometry for identifying a minor component in an unseparated mixture of proteins.     

Time,Complex Systems,and Public Policy: A Theoretical Foundation for Adaptive Policy Making

Nonlinear Dynamics, Psychology, and Life Sciences - Can public policy development and implementation be improved by closely tracking and coordinating its timing with that of the regulated sector?...     

Mechanism Study for Thermal/Electric Field Poling of Fused Silica

On the basis of the experimental reports, the mechanism of the second-order susceptibility ⁽²⁾ for the thermal/electric field poling of fused silica is analyzed, and expressions for ⁽²⁾ are detailedly derived and numerically calculated for the first time. By comparison the theoretical value of ⁽²⁾ with the experiment results, we propose that the effective ⁽²⁾ is created via both the interaction of the intense electric field with the third-order susceptibility ⁽³⁾ and the dipole orientation. The theoretical results show that, in the differently applied voltage, the dipole orientation and ⁽³⁾ play different role in the formation of ⁽²⁾. This theory successfully explains some experiment results.     

激子自旋弛豫对简并量子点发射光子对纠缠度的影响

利用粒子数运动方程和量子回归理论，计算了单个半导体量子点双激子体系脉冲激发下粒子在各能级间辐射跃迁的二阶交叉相关函数以及系统发射光子对的偏振密度矩阵.分析了激子态能级简并量子点体系发射光子对偏振纠缠特性，讨论了纠缠度随激子态间自旋弛豫的变化关系.研究表明，激子自旋弛豫会破坏该系统发射光子对的纠缠度. 关键词： 纠缠光子对 半导体量子点 二阶相关函数     

基于灰度相关的图像匹配算法的改进

针对目前图像匹配算法中存在的匹配精度不高和匹配速度慢的缺点，对基于灰度相关的2类匹配算法——最小误差法和相关系数法进行了改进。最小误差法采用新的ML距离法，提出动态调整阈值的方法，既保证了匹配精度，又避免了局部噪声的影响；相关系数法对相关系数的计算公式进行了简化，并采用三步搜索策略进行匹配，以达到减少计算量和搜索位置的目的。实验证明：改进后的算法，在保证一定匹配精度的条件下，匹配速度大大提高，能够满足实际应用中的实时性要求。