内爆初级质子能谱直接测量方法

基于单能质子对CR39的标定实验,利用获取的响应曲线,设计了一种内爆初级质子的直接测量方法。在内爆初级质子产额较低的情况下,该方法可获得更多的计数。对实验中的噪声信号排除做出了说明,并对其背景噪声来源进行了分析,以提高实验数据的精确性。利用标定数据,对CR39上观察到的径迹进行鉴别,确定质子径迹并测量其径迹参数,从而确定质子能量。在随机扫描的约300个显微镜视场中获得了200个质子径迹数据,并通过与标定数据比对,获得了它们各自的能量,再利用蒙特卡罗程序Geant4修正铝膜的岐离,最终确认本次内爆实验初级质子的能谱峰值应该在2.4~2.6 MeV之间,据此换算到靶丸面密度为7~8mg/cm2,为实验结果的进一步后续分析提供了依据。     

Pulse Self-trapping Robustness to Polarization Mode Dispersion in Optical Fiber

In this paper, pulse self-trapping robustness to polarization mode dispersion in optical fibers is studied. Nonlinear pulse can be used to suppress PMD despite the input pulse shapes is found. When the nonlinear effect is stronger (initial pulse amplitude is larger), the suppression degree to PMD is better. As the initial chirp is considered, we find that the chirp is harmful to suppress PMD. The more is initial chirp, the more is the PMD value.     

Towards a Neo-Copenhagen Interpretation of Quantum Mechanics

The Copenhagen interpretation is critically considered. A number of ambiguities, inconsistencies and confusions are discussed. It is argued that it is possible to purge the interpretation so as to obtain a consistent and reasonable way to interpret the mathematical formalism of quantum mechanics, which is in agreement with the way this theory is dealt with in experimental practice. In particular, the essential role attributed by the Copenhagen interpretation to measurement is acknowledged. For this reason it is proposed to refer to it as a neo-Copenhagen interpretation.     

热辐射体真实温度的测试研究

在辐射测温中，普遍存在一个问题，被测温度物体表面发射率影响很大，而物体的发射率很难确测量，这是因为发射率不仅与材料有关，而且还与波长，温度，表面状态（表面粗糙度，氧化程度等）有关，本文叙述一种利用多波长辐射法测量实际物体真实温度的方法，该方法利用最小二乘法原理拟合出实际热辐射体的光谱发射率曲线，从而使测量目标的真实温度成为可能。     

Wave-induced bed flows by a Lagrangian vortex scheme

Nominally 2-dimensional viscous flow induced by gravity waves over a spatially periodic bed is simulated by a Lagrangian vortex scheme. A vortex sheet is introduced on the surface at each time step to satisfy the zero velocity conditions. The sheet is discretised; the vortex-in-cell method is used to convect vorticity and random walks are added to effect viscous diffusion. Good agreement with analytical theory is obtained for velocity profiles in uniform sinusoidal flow and for mass transport due to linear waves. Mass transport for finite amplitude waves is also obtained. For separated flow over rippled beds, which is still liminar, a vortex decay factor is required to produce agreement with experiment and is thought to compensate for large scale 3-dimensional effects.     

超短脉冲激光选通电子学全息成象系统研究

本文介绍了最早到达光概念，分析了超短脉冲激光电子学全息实现选通最早到达光成象的原理．用超短脉冲激光拍摄全息图，相当于用多色光记录全息图，当用单色光再现这种全息图时，会给再现象造成一个模糊量．在一般全息理论中，只讨论了采用单色光记录全息图，复色光再现所造成的模糊量．因此，本文中讨论的是一个与此相反的问题，即用多色光记录全息图，单色光再现的情况，并且着重讨论了超短脉冲激光记录全息图的情况．最后得出结论，在用超短脉冲激光拍摄全息图时，最好采用象面全息术．     

麦克斯韦速率分布的特色推导方法

大学物理教学的一个基本点是培养学生的空间想象力.麦克斯韦速率分布律是气体分子运动论的中心内容,是大学物理气体运动理论中讲授的一个难点,其公式抽象、繁难,学生不易理解.本文根据速度空间概念,给出速度球的表面积相当于气体分子微观状态数的观点,利用拉郎格日函数,推导理想气体平衡态下气体分子的速率分布函数.这种推导方法相对比较简单、易学,便于学生理解和培养学生的空间想象力.     

超短脉冲激光选通电子学全息成象系统研究

本文介绍了最早到达光概念,分析了超短脉冲激光电子学全息实现选通最早到达光成象的原理.用超短脉冲激光拍摄全息图,相当于用多色光记录全息图,当用单色光再现这种全息图时,会给再现象造成一个模糊量.在一般全息理论中,只讨论了采用单色光记录全息图,复色光再现所造成的模糊量.因此,本文中讨论的是一个与此相反的问题,即用多色光记录全息图,单色光再现的情况,并且着重讨论了超短脉冲激光记录全息图的情况.最后得出结论,在用超短脉冲激光拍摄全息图时,最好采用象面全息术.     

Speckle noise reduction in digital holography with spatial light modulator and nonlocal means algorithm

An integrated method based on optical and digital image processing is presented to suppress speckle in digital holography. A spatial light modulator is adopted to introduce random phases to the illuminating beam. Multiple holograms are reconstructed and superimposed, and the intensity is averaged to smooth the noise. The adaptive algorithm based on the nonlocal means is designed to further suppress the speckle. The presented method is compared with other methods reduction is improved, and the proposed method is effective The experimental results show that speckle and feasible.     

非合作目标相位式激光测距接收光功率的模型建立

在相位式激光测距中,接收光功率的大小直接决定了测量信噪比,从而决定了测量范围和测量精度,因此如何准确地计算出接收光功率的大小,是测距技术中一个非常重要的问题。对普遍使用的计算接收光功率公式的适用范围进行了讨论,指出了其不适用于非合作目标短距离测量的原因。提出了适于非合作目标相位式激光测距的计算接收光功率的新方法,推导了计算公式,并进行了仿真计算。     

两个玻色-爱因斯坦凝聚体间相互作用的数值研究

本文采用辛算法数值求解一维含时Gross-Pitaevskii(GP)方程.研究了存在陷俘势和撤掉陷俘势时两个凝聚体间的相互作用.发现当存在陷俘势时两个凝聚体间发生弹性碰撞;在零时刻撤掉陷俘势时两个凝聚体间发生干涉现象;当t=2时撤掉陷俘势两个凝聚体间发生了复杂现象.     

三维可逆混沌映射的图像加密算法

提出了一种三维可逆混沌映射图像加密算法。基于Line map二维混沌可逆映射,推导了该三维可逆映射的数学表达式。将灰度图像用一个三维矩阵数据描述,并按照所提出的算法将其组成一个二维的二进制图像。首先对此图像应用Line map二维混沌可逆映射进行像素置乱处理,然后再将置乱后的二进制图像还原成十进制的灰度图像,这样就得到了加密后的图像。所提出的方法可以通过一次三维可逆混沌映射同时实现图像加密的两个步骤,即像素置乱和像素混淆。仿真实验结果表明了该算法的有效性,且加密速度快、安全性高、简单易行。     

A quantum Hamilton–Jacobi proof of the nodal structure of the wave functions of supersymmetric partner potentials

Quantum Hamilton–Jacobi formalism is used to give a proof for Gozzi’s criterion, which states that for eigenstates of the supersymmetric partners, corresponding to the same energy, the difference in the number of nodes is equal to one when supersymmetry (SUSY) is unbroken and is zero when SUSY is broken. We also show that this proof is also applicable to the case, where isospectral deformation is involved.     

Finsler gauge transformations and general relativity

The theory of gauge transformations in Finsler space is applied to general relativity. It is seen that the transformations produce new metrics which correspond to the introduction of physical fields. The geodesic equation in the transformed space is equivalent to the equation of motion in the original space where the field is included by a force term. An example is given of a transformation and resulting metric in which the electromagnetic potential is related to parameters of the gauge transformation rather than to gauge potentials. This implies that the electromagnetic field corresponds to a connection instead of a curvature. Another example is given which shows how Weyl or conformal transformations are related to a class of the gauge transformations.     

Nonlinear amplitude approximation for bilinear systems

An efficient method to predict vibration amplitudes at the resonant frequencies of dynamical systems with piecewise-linear nonlinearity is developed. This technique is referred to as bilinear amplitude approximation (BAA). BAA constructs a single vibration cycle at each resonant frequency to approximate the periodic steady-state response of the system. It is postulated that the steady-state response is piece-wise linear and can be approximated by analyzing the response over two time intervals during which the system behaves linearly. Overall the dynamics is nonlinear, but the system is in a distinct linear state during each of the two time intervals. Thus, the approximated vibration cycle is constructed using linear analyses. The equation of motion for analyzing the vibration of each state is projected along the overlapping space spanned by the linear mode shapes active in each of the states. This overlapping space is where the vibratory energy is transferred from one state to the other when the system switches from one state to the other. The overlapping space can be obtained using singular value decomposition. The space where the energy is transferred is used together with transition conditions of displacement and velocity compatibility to construct a single vibration cycle and to compute the amplitude of the dynamics. Since the BAA method does not require numerical integration of nonlinear models, computational costs are very low. In this paper, the BAA method is first applied to a single-degree-of-freedom system. Then, a three-degree-of-freedom system is introduced to demonstrate a more general application of BAA. Finally, the BAA method is applied to a full bladed disk with a crack. Results comparing numerical solutions from full-order nonlinear analysis and results obtained using BAA are presented for all systems.     

Pulse Self-trapping Robustness to Polarization Mode Dispersion in Optical Fiber

In this paper, pulse self-trapping robustness to polarization mode dispersion in optical fibers is studied. Nonlinear pulse can be used to suppress PMD despite the input pulse shapes is found. When the nonlinear effect is stronger (initial pulse amplitude is larger), the suppression degree to PMD is better. As the initial chirp is considered, we find that the chirp is harmful to suppress PMD. The more is initial chirp, the more is the PMD value.     

太阳能光伏-热伏发电板的自适应追光系统设计与实现

在小型太阳能光伏-热伏发电系统中,为了提高其发电效率,通常会辅以自动追光系统。针对现有的基于多光电二极管的自动追光系统结构复杂等问题,提出了一种基于光敏电阻的自适应追光系统。为了实现发电板对光源的追踪,采用了基于负反馈的自适应追光原理,通过软件设计控制追光精度,同时增加了系统位置消抖控制。在硬件方面,采用光敏电阻感应光强,借助AD转换电路和舵机,以驱动太阳能光伏-热伏发电板转动直至发电板平面垂直于太阳光;优化设计了光敏电阻与板面的夹角大小以调整追光的区域及误差。最后完成了整体装置的机械结构设计和电路图设计及仿真,结果表明,与现有的多光电二极管追光系统相比,所设计的追光系统机械装置部分的设计更加简单,便于实现,同时通过优化设计改善了追光的稳定性。     

Role of kinetic effects on the polarization current around a magnetic island

The polarization current due to a magnetic island rotating in a tokamak plasma is believed to play a central role in the initial evolution of the neoclassical tearing mode. Monte Carlo delta f simulations are performed which also cover a parameter range that is not amenable to analytic treatment but is relevant to experiments. It is shown that the polarization current can change sign when the island rotation frequency is of the order of the ion parallel streaming around the island. Moreover, the current is reduced when the island width is of the order of the ion banana width. Finally, the transition to the enhanced high-collisionality regime is shown to occur for collision frequencies higher than those typical of today's experiments.