高自由度体系微振动本征模式的求解方法

介绍两种求解高自由度体系微振动本征模式的方法．第一种方法：利用对称性经过物理分析寻找本征模式；第二种方法：利用对称性降低体系的自由度，然后用求解本征模式的一般方法解之．     

不同能区核-核碰撞实验中高多重数,大起伏的事件性质的分析-与物理模型无关的统计分析

报道了用不依赖于任何物理模型的纯数理统计的方法对EMU01实验组200A GeV的³²S与固定的Au靶碰撞中较高多重数和较大起伏事例的数据和STAR实验组在核-核质量中心能量为\sqrt{s_{_{\rm NN}}}=200GeV的Au+Au碰撞中较高多重数和较大起伏事例的数据所做的分析. 对3个相差很远的能区——固定靶加速器能区, 核-核对撞机能区以及宇宙线能区所得的分析结果进行了比较, 并对所得的结果进行了讨论.     

组合利用统计和结构信息的道路提取算法

提出了一种组合利用统计和结构信息从遥感图像中提取道路的算法,这个算法包括三个处理步骤,利用道路的多种局部统计特性获得道路基元与道路段,以及利用能量函数提取道路边沿,在检测道路基元时,用统计分析来表达道路的结构信息,避免了提取线段来表达,增强了抗噪性与稳健性;在检测和拟合道路边沿时,能量函数中的参数由前面的运算结果确定,使算法具有自适应能力。     

Magnetic properties of Ising metamagnet in both external longitudinal and transverse fields

The phase diagrams of a two-sublattice Ising metamagnet at finite temperature in a mixed longitudinal field and a transverse magnetic field are investigated by the use of an effective-field theory (EFT) with correlations. In addition to the second-order transition lines, the first-order transition lines are also presented in the phase diagrams, since the Gibbs free energy can be calculated numerically. The results show that there is no fourth-order critical line in the phase diagrams given by using EFT as found by using mean-field theory (MFT). The tricritical lines and their projection in the t−h_x plane obtained by using EFT are also quite different from those by using MFT. Only one type of phase diagram is obtained by using EFT while three kinds of phase diagrams are obtained by using MFT, which indicates that only the first kind of phase diagrams obtained by using MFT is reliable. Furthermore, it is shown that the region of first-order transitions increases as the transverse magnetic field h_x decreases.     

3维全电磁粒子模拟大规模并行程序NEPTUNE

 介绍了自主编制的3维全电磁粒子模拟大规模并行程序NEPTUNE的基本情况。该程序具备对多种典型高功率微波源器件的3维模拟能力,可以在数百乃至上千个CPU上稳定运行。该程序使用时域有限差分(FDTD)方法更新计算电磁场,采用Buneman-Boris算法更新粒子运动状态,运用质点网格法（PIC）处理粒子与电磁场的耦合关系,最后利用Boris方法求解泊松方程对电场散度进行修正,以确保计算精度。该程序初步具备复杂几何结构建模能力,可以对典型高功率微波器件中常见的一些复杂结构,如任意边界形状的轴对称几何体、正交投影面几何体,慢波结构、耦合孔洞、金属线和曲面薄膜等进行几何建模。该程序将理想导体边界、外加波边界、粒子发射与吸收边界及完全匹配层边界等物理边界应用于几何边界上,实现了数值计算的封闭求解。最后以算例的形式,介绍了使用NEPTUNE程序对磁绝缘线振荡器、相对论返波管、虚阴极振荡器及相对论速调管等典型高功率微波源器件进行的模拟计算情况,验证了模拟计算结果的可靠性,同时给出了并行效率的分布情况。     

AL L CORE EDGE FINE STRUCTURE IN Al, AlN AND α-Al2O3：A COMPARISON OF MICROELECTRON ENERGY LOSS SPECTRA WITH THEORY

The Al L near-edge fine structures of aluminum and its compounds with nitrogen and oxygen are studied using electron energy loss microspectroscopy in a transmission electron microscope. These edges are normalized to the same scattering cross section per Al atom per electronvolt. The cross section is calculated by using the Born approximation. The contributions to the cross section are from the valence shell crystal states obtained by using the extended Hückel band calculation and the ionization states obtained by using the electron gas model. The chemical effects in the ionization region are taken into account by in cluding the contributions from the elastic backscattering of outgoing plane waves by the atoms that neighbor the excited atoms. The results by theoretical calculation agree semiquantitatively with experimental results.     

Response characteristics of local vibrations in stay cables on an existing cable-stayed bridge

This paper examines local parametric vibrations in the stay cables of a cable-stayed bridge. The natural frequencies of the global modes are obtained by using a three-dimensional FE model. The global motions generated by (1) sinusoidal excitations using exciter, (2) a traffic loading, and (3) an earthquake are analyzed by using the modal analysis method or the direct integration method. The local vibration of stay cable is calculated by using a model in which inclined cable is subjected to time-varying displacement at one support during global motions. This paper describes the properties of the local vibrations in stay cables under these dynamic loadings by using an existing cable-stayed bridge.     

Theoretical studies on the SiC radical: electronic structure, spectroscopy and spin-orbit couplings

The potential energy curves (PECs) of twenty-five ??-S states and twenty ?? states generated from eight ??-S states of the SiC radical are calculated by using an ab initio quantum chemical method. The PEC calculations are performed for internuclear separations from 0.10 to 1.00 nm using the complete active space self-consistent field method, which is followed by the internally contracted multireference configuration interaction (MRCI) approach in combination with a correlation-consistent aug-cc-pV6Z basis set. To improve the quality of the PECs, core-valence correlation and relativistic corrections are included. Core-valence correlations are included using a cc-pCVTZ basis set. Relativistic corrections are calculated using the third-order Douglas-Kroll Hamiltonian approximation at the level of cc-pV5Z basis set. The spin-orbit coupling effect is accounted for by the Breit-Pauli Hamiltonian in combination with the aug-cc-pVTZ basis set. To obtain more reliable results, the PECs determined by the MRCI calculations are corrected for size-extensivity errors by means of the Davidson modification. The PECs are extrapolated to the complete basis set (CBS) limit by the total-energy extrapolation scheme. The spectroscopic parameters are obtained by fitting the vibrational levels, which are calculated by solving the ro-vibrational Schr?dinger equation using the Numerov??s method. The spectroscopic results are compared with those reported in the literature. Excellent agreement has been found between the present results and the measurements. The vibrational manifolds of the first 30 vibrational states are calculated for each electronic state of the non-rotating radical. Comparison with the measurements demonstrates that the present results are accurate. The spectroscopic parameters and the molecular constants reported here are expected to be reliable predicted results.     

Binding energies of impurity states in strained wurtzite GaN/Al_xGa_(1-x)N heterojunctions with finitely thick potential barriers

Ground state binding energies of donor impurities in a strained wurtzite GaN/AlxGal_xN heterojunction with a po- tential barrier of finite thickness are investigated using a variational approach combined with a numerical computation. The built-in electric field due to the spontaneous and piezoelectric polarization, the strain modification due to the lattice mismatch near the interfaces, and the effects of ternary mixed crystals are all taken into account. It is found that the binding energies by using numerical wave functions are obviously greater than those by using variational wave functions when impurities are located in the channel near the interface of a heterojunction. Nevertheless, the binding energies using the former functions are obviously less than using the later functions when impurities are located in the channel far from an interface. The difference between our numerical method and the previous variational method is huge, showing that the former should be adopted in further work for the relevant problems. The binding energies each as a function of hydrostatic pressure are also calculated. But the change is unobvious in comparison with that obtained by the variational method.     

三维各向同性谐振子的守恒张量及其轨道方程

从牛顿第二定律出发，得到了三维各向同性谐振子的守恒张量，证明了守恒张量能提供一个独立的常数，并运用守恒张量的分量表示谐振子的运动方程，铁道平面方程，长轴和短轴所在直线方程及新坐标系下的轨道方程。     

类锂碳离子能级,波函数和跃迁几率

用组态相互作用程序ＣＩＶ３计算了类锂碳离子能级、波函数和跃迁几率，并与相对论多组态ＤｉｒａｃＦｏｃｋ程序ＭＣＤＦ的计算结果进行了比较。两种方法的结果符合得很好。     

用板式电位差计测电池的电动势和内阻的实验研究

给出了用板式电位差计测电池电动势和内阻的原理与方法,分析了如何选取电路中的电池E、标准电阻Rs和限流电阻R的取值,使实验效果最佳。运用最小二乘法处理实验数据,实验结果令人满意。     

Accelerating distributed average consensus by exploring the information of second-order neighbors

The problem of accelerating distributed average consensus by using the information of second-order neighbors in both the discrete- and continuous-time cases is addressed in this Letter. In both two cases, when the information of second-order neighbors is used in each iteration, the network will converge with a speed faster than the algorithm only using the information of first-order neighbors. Moreover, the problem of using partial information of second-order neighbors is considered, and the edges are not chosen randomly from second-order neighbors. In the continuous-time case, the edges are chosen by solving a convex optimization problem which is formed by using the convex relaxation method. In the discrete-time case, for small network the edges are chosen optimally via the brute force method. Finally, simulation examples are provided to demonstrate the effectiveness of the proposed algorithm.     

Dynamic recording of a digital hologram with single exposure by a wave-splitting phase-shifting method

The wave-splitting phase-shifting digital holography using a pixelated microretarder array is proposed. By using four intensity images recorded by the pixelated microretarder array, Stokes parameters of the incident wave can be calculated. The fully complex amplitude distribution of the object wave can be obtained by using Stokes parameters, if the polarization states of the object and reference waves are linear and orthogonal. Two sets of experimental results are provided to verify the feasibility of the proposed method. One is the result for a movie recording using a CW laser and the other is the result for instant recording using a single pulsed laser.     

机载激光测深系统中海面波浪影响的改正

针对研制的新型机载激光测深系统的海上飞行试验数据,进行预处理、信息提取、数据同步和坐标转换后,开展波浪改正研究.对海底高程的GPS高程信息无波浪改正、GPS高程信息改正飞机航高变化计算波浪和加速度信息改正飞机航高变化计算波浪三种技术进行了分析.数据处理结果表明,采用加速度信息改正飞机航高变化计算得到的波浪信息的方法,结果较好,可满足研制的机载激光测深系统的要求.     

利用相位型衍射光栅生成能量按比例分布的多个螺旋光束的研究

研究了基于计算全息光栅的方法产生能量按比例分布的多个螺旋光束的技术.在计算全息光栅的过程中引入了Gerchberg-Saxton迭代算法,并在此基础上利用位相型空间光调制器产生了具有轨道角动量态的多种光束,实现了多个指定轨道角量子数的螺旋光光场分布.给出了计算机仿真结果和实验结果,表明利用Gerchberg-Saxton迭代算法生成的位相型光栅可以生成多个指定轨道角动量量子数的光束,研究结果对于利用轨道角动量进行信息传输有益.     

Replicated data-matrix array generators

The fabrication and replication of binary spot array generators using 4 and 16 levels gratings is investigated. The elements are designed using iterative Fourier transform algorithm and fabricated by electron-beam lithography. Finally elements are copied by fabricating nickel shims and using hot embossing technique. In each step the optical signals are measured and signals are characterized using bit error rate as a measure of quality. The results show that although 16 level element gives theoretically superior performance, the bit error rate is much lower (∼0.2%) for replicated 4 level elements than for their 16 level counterparts (∼9%).     

用图像运算技术对光弹性条纹进行倍增

在光弹应力分析中,利用分数级条纹可以提高分析精度,于是,产生分数级条纹的方法研究就变得非常重要。利用图像处理技术,首先采集一幅图像,然后通过对这幅图像的算术运算就可以产生分数级条纹。给出了详细的理论分析,并进行实验。利用本文方法,在两条整数级条纹之间,可以相继产生７条分数级条纹。     

自由电子激光辐射场的经典理论分析

以经典电动力学分析自由电子激光辐射场,讨论辐射场的一般特性,并利用麦克斯韦方程组、波动方程、电子连续性方程以及相对论电子运动的洛伦兹力方程和能量方程一起系统地建立了自由电子激光辐射场的自洽解方法. 关键词：     

A Review of Online Real-Time Process Analyses of Melt-State Polymer Using the Near-Infrared Spectroscopy and Chemometrics

Abstract

This review describes the online process monitoring of the melt-state polymer by near-infrared (NIR) spectroscopy and chemometrics. The spectra of linear low-density polyethylene (LLDPE), random polypropylene (RPP), block polypropylene (BPP), and ethylene-vinylacetate (EVA) copolymer in melt states measured by an online monitoring system with a Fourier transform near-infrared spectrometer are discussed. The calibration models for the density of LLDPE, the content of ethylene copolymers in RPP and BPP, and vinylacetate concentration (VA) in EVA copolymers using partial least squares regression are reported. The continuous monitoring of the LLDPE density at the real plant is described as an example of online monitoring using NIR spectroscopy and chemometrics. For the precise prediction of VA in EVA, a combination method using regression and discrimination was inducted. Three compensation methods for the effect of the temperature change in the RPP and BPP samples are shown. Conventional calibration transfer methods are introduced, and a practical calibration transfer method using two samples and its performance are reported using BPP and RPP spectra. Moreover, the possibility of a calibration correction method using one sample for the realization of long-term traceability is indicated by the example of the relocation.