云层对卫星遥感大气CO的影响与修正方法研究

研究云层对卫星遥感大气CO精度的影响,并以SCIAMACHY观测为例,详细论述一种云层影响的修正方法。修正过程中,采用朗伯云模型,全面考虑云层覆盖率、云顶高度和地面反射率的影响。将云层影响修正前后的卫星CO反演结果与地基FTIR测量值进行对比,发现修正云层影响后,两者的测量相关性明显提高。实验结果表明,提出的云层影响修正方法可明显提高卫星遥感大气CO的精度。     

J-PARC多峰离子源体积产生效率三维数值模拟研究

深入阐述了拥有自主知识产权的粒子模拟-蒙特卡罗算法, 并采用该算法数值研究了J-PARC多峰离子源放电特性, 分析了J-PARC离子源的放电机理, 并在单、双校正磁体下讨论了该离子源体积产生效率. 结果显示: 在单校正磁体下, 校正磁体中心与离子源顶端相距50 mm时, 体积产生效率最大; 在双校正磁体且固定顶端磁体下, 两磁体相距越大体积产生效率越低.     

Conditions for identical position of optimal image plane for axial imaging with different values of f-number

By analysis of the dependence of longitudinal spherical aberration on the numerical aperture, it is possible to find such values of the numerical aperture, where spherical aberration is zero. Such values of the numerical aperture are called correction zones. The work theoretically analyses the described problem and equations are given for wave aberration coefficients using correction zones for spherical aberration of the third and the fifth order. Our work presents an analysis of optimal values of correction zones and an optimal position of the center of the reference sphere based on the variance of wave aberration for the image quality evaluation. Relations are described for calculation of correction zones of an optical system having an identical position of the optimal image plane for two values of the f-number. The analysis of optical systems using correction zones is performed on an example.     

TDI CCD像元响应不一致性校正算法

线阵TDI CCD遥感相机的不一致性校正对获取高质量的图像来说具有重要意义。主要对TDI CCD像元响应不一致性的校正算法及其硬件实现进行了深入的研究。对CCD的噪声特性进行了详细的分析,给出了像元响应不一致性(PRNU:Pixel-response non-uniformity)的退化模型及校正算法,并对其计算精度进行了分析,在硬件电路上对校正算法进行了验证,详细分析了影响校正效果的各种因素。实测结果表明,校正后图像的信噪比得到显著提高。     

Activity in manufacturing and characterization of X-ray optical elements and ultrahigh-resolution systems at IPM RAS

The latest developments in the field of metrology and correction of high-ratio substrates for X-ray optics with a subnanometer scale accuracy, carried out at the Institute for Physics of Microstructures (IPM), Russian Academy of Sciences, are reported. A scheme of an interferometer with a diffracted reference wave, based on a single-mode fiber with a narrowed exit aperture, is reported. Some methods for shape correction are described.     

Comparison study of exchange-correlation functionals on prediction of ground states and structural properties

Despite significant advances in first-principles calculation methods, there is no single exchange-correlation functional which predicts the ground state of materials without an error yet. We investigated how accurately ground states of binary semiconductors are described using 16 exchange-correlation functionals (with or without van der Waals corrections). LDA, PBEsol, SCAN (with or without rVV10 correction), and PBE with D3 van der Waals correction (zero or Becke-Johnson damping) show good predicting power. The lattice constants of stable phases were slightly better described by SCAN, PBEsol, PBE+D3 (Becke-Johnson damping), and MS2. We also propose a set of functionals to double-check the stability of new materials based on the majority vote.     

Sequence of phase correction in multiconjugate adaptive optics

The way in which the sequence of phase correction impinges on performance in multiconjugate adaptive optics systems is described. When multiple phase modulators with different conjugate ranges are used, the conjugate images of the phase modulators in the atmosphere must be reimaged in the reverse order post focus, and adaptive phase correction applied in this sequence for perfect amplitude and phase cancellation. Performing the correction without relay optics results in residual amplitude and phase aberrations. It is shown, by Monte Carlo simulations of Fresnel propagation, that the effects of wave optical propagation become nonnegligible at visible wavelengths and for large air masses.     

基于MATLAB的合肥光源储存环束流轨道校正系统

 闭轨畸变对合肥同步光源的束流质量产生负面影响，因此必须对闭轨畸变进行校正。本文介绍了基于MATLAB的合肥光源储存环束流轨道校正系统的工作原理、开发过程及测试结果。该系统由束流轨道测量系统、校正铁系统和控制系统组成，基于MATLAB开发的束流轨道校正程序运行于操作员界面工作站上。首先对获取的束流轨道数据进行分析和计算，然后通过控制系统改变校正铁电源的电流以改变校正铁磁场强度，从而实现轨道校正。测试结果表明：束流轨道的最大畸变由校正前的4.468 mm下降到校正后的0.299 mm；标准方差（SDEV）由校正前的2.986 mm下降到校正后的0.087 mm。该系统达到了设计目标。     

On the theory of magnetoresistance of binary composites in a weak magnetic field: Numerical experiment

A correction to the electric field strength linear in magnetic field H was found by computations for a two-dimensional disordered system. This correction was used to calculate and graphically tabulate two two-parameter functions present in the equation describing magnetoresistance in a wide range of parameter variations. This correction was also used to determine and tabulate the derivative of the function present in the equation for the effective Hall coefficient with respect to one of its arguments. The data obtained in this work combined with the earlier results of these authors allow the magnetoresistance of binary (composite) media to be completely described in the spirit of the similarity hypothesis.     

轻元素定量分析的新修正方法

本文介绍了一种能用于轻元素定量分析的新修正方法,它的各项修正因子用Monte Carlo计算方法确定。分析了碳和氧两种元素,计算得到的浓度结果比其它方法好。并对ZAF方法中的简化Philibert吸收修正公式和Dancumb-Reed原子序数修正公式进行了详细讨论,指出了它们的局限性。 关键词：     

基于FPGA的红外图像处理与实时显示系统研究

介绍了基于FPGA的红外图像处理与实时显示系统的工作原理。针对传统的红外焦平面阵列(IRFPA)非均匀性校正算法的不足，提出了对采用神经元法和两点线性法校正其非均匀性算法的改进，重点介绍了两点线性法的软硬件实现方式，该算法在Spartan系列FPGA上实现并获得成功。     

基于DSP的红外焦平面阵列非均匀性实时压缩校正研究

针对红外成像系统在图像处理中所涉及的数据量大,实时处理难于实现的特点,利用高速DSP硬件对红外焦平面阵列的非均匀性进行实时压缩校正.以两点校正为例,详细阐述了硬件压缩校正原理和实现步骤,并给出实验结果.实验表明:基于DSP的非均匀性实时压缩校正系统生成的图像比较清晰,校正过程简单,程序调试方便,能够有效地解决红外成像技术中实时性难题.     

锕系原子核自发裂变性质的理论研究

运用推广的液滴模型（GLDM）来确定锕系原子核的自发裂变势垒, 采用量子力学中的WKB近似方法对相应自发裂变的半衰期进行了研究。 在GLDM中, 首次考虑了微观Strutinsky壳修正对裂变势垒的影响。 理论计算的锕系区重核自发裂变半衰期与实验值符合得很好, 表明包括微观壳修正的GLDM可以成功研究重核的自发裂变性质。 The spontaneous fission half lives of the actinides are calculated by the WKB approximation and the potential barriers are constructed by a General Liquid Drop Model (GLDM) including the proximity energy, the mass and charge asymmetry, and an accurate nucleus radius. The microscopic shell correction which plays a key role for the spontaneous fission barrier is considered for the first time. The two parameter quasi molecular shape and the proximity are described in details within the GLDM. The effects of the microscopic shell correction and proximity energy for fission barrier are discussed separately. The calcula ted spontaneous fission half lives for the actinides reasonably accord with the experimental data, implying the present GLDM combined with the microscopic shell correction can be used to study the spontaneous fission properties of heavy nuclei successfully.     

Evaluation of nuclear shell correction energies for realistic level schemes by temperature smearing method

Calculations of shell correction energies by the temperature smearing method for realistic single particle level schemes of finite depth potentials are described and discussed. It is found that the method provides unique values of the shell correction energies for the various shapes relevant in the fission of actinide nuclei including those shapes where breakdown of the usual Gaussian energy smearing procedure was observed.     

同步加速器中束流能量的修正

叙述了同步加速器中束流能量测量和修正的原理,推导出关于闭合轨道畸变和校正二极子强度的束流能量的修正公式,介绍了这些公式在北京正负电子对撞机（BEPC）上的应用,并对其结果进行了讨论．     

Neutrino oscillations in the gravitational field

We calculate the gravitational correction to the phase difference between neutrino mass eigenstates for the spherically symmetric gravitational field described by the Schwarzschild metric. This correction was calculated in a number of works, but the results of these works differ from each other. Our result does not coincide with the results ever published. In this work, we make calculations in the simplest way and verify our result by several tests.     

Aberration correction using a multi-segment mirror with feedback interferometry

A novel real-time aberration correction system using feedback interferometry and a multi-segment mirror for the wavefront corrector is described. The result is a simple and high-speed adaptive optics system demonstrating that feedback interferometry may potentially be an alternative method to conventional aberration correction techniques. Its high-speed processing and simplicity makes real-time correction practical. Our results show that the system can respond up to 37 Hz for sinusoidal phase variations with amplitude of one wavelength and improves Strehl ratio significantly.     

Motion correction properties of the shells k-space trajectory

The feasibility of a k-space trajectory that samples data on a set of 3D shells is demonstrated with phantom and volunteer experiments. Details of an interleaved multi-shot, helical spiral pulse sequence and a gridding reconstruction algorithm that uses Voronoi diagrams are provided. The motion-correction properties of the shells k-space trajectory are described. It is shown that when used in conjunction with three point markers, k-space data acquired with the shells trajectory provide a generalization of the RINGLET method, allowing for correction of arbitrary rigid-body motion with six degrees of freedom. Use of dedicated navigator echoes or redundant acquisitions of k-space data are not required. Retrospective motion correction is demonstrated with controlled phantom experiments and with seven healthy human volunteers. The motion correction is shown to improve the images, both qualitatively and quantitatively with a metric calculated from image entropy. Advantages and challenges of the shells trajectory are discussed, with particular attention to acquisition efficiency.     

一种基于全息术的光学系统闭环像差补偿方法

提出了一种基于21单元变形镜与全息波前传感器的全息自适应光学系统, 并对其像差校正能力进行了分析. 首先描述了全息波前传感器基本原理, 并在薄全息图近似下给出基于快速傅里叶变换算法的全息波前传感器数值模型; 然后基于21单元变形镜的数值模型, 分析了该变形镜的波前校正能力; 在此基础上, 数值模拟并实验验证了全息自适应光学系统对静态像差的闭环校正能力.     

NDIR多组分气体分析的干扰修正方法研究

介绍了非分散红外(Non-Dispersive Infrared,NDIR)多组分气体分析的一种干扰修正方法.根据逐次积分气体吸收模型和方法,并考虑温度和气压对积分线强和线型的影响,选择洛伦兹展宽线型,得到了CO,CO2,NO和H2O在各个滤波通道的响应系数.利用响应系数建立了用于干扰修正的四元线性回归方程组,通过求解...