On the character of local electric fields in amorphous semiconductors

On the basis of the agreement of calculated and measured parameters of some amorphous semiconductors, an argument is stated in favour of the central-symmetric type of random local electric fields. A possible mechanism of the transport of electrons is discussed.     

电气线路互联系统线缆抗高空核电磁脉冲耦合效应

高空核电磁脉冲（HEMP）对电子设备的耦合途径主要有两方面：一方面是通过装备（产品）上的天线耦合通道进入到电子系统内的“前门耦合”方式;另一方面则是“后门耦合”,即通过装备（产品）上的壳体、电源线、电缆、机箱的缝隙、孔洞等途径进行耦合。主要研究电气线路互联系统(EWIS)线缆抗高空核电磁脉冲耦合效应,通过研究HEMP干扰的特征、能量分布,搭建HEMP数学模型,采用控制变量法,改变EWIS线缆类型、离地高度等要素,通过在CST上建立仿真模型以及开展试验,分析HEMP对电子设备造成的影响程度,得到HEMP耦合效应的一般性结论与规律。     

原子激发态在高频强激光作用下的光电离研究

本文通过数值求解动量空间的三维含时薛定谔方程, 研究了原子高激发态在高频激光脉冲作用下, 在电离阈值附近的光电子能谱和两维动量角分布. 研究结果表明: 在该能量范围内, 单光子电离过程的贡献是最主要的. 体系初态的主量子数可以由光电子能谱峰值的位置来确定; 体系初态的角量子数可以通过光电子的两维动量角度分布确定. 在比较宽泛的参数范围内, 这一规律不随入射激光的强度和脉冲时间宽度的改变而改变, 因此原则上可以利用它对原子的初态进行识别. 此外, 还研究了体系的初态为相干叠加态, 光电子动量谱随着叠加态相对相位的变化规律. 关键词： 阈上电离 激发态 高频激光脉冲 两维动量角度分布     

Phenomenology of the Λ/Σproduction ratio in pp collisions

We show that the recently measured asymmetry in helicity-angle spectra of the Λ-hyperons, produced in the reaction pp → K ⁺Λp reaction, and the energy dependence of the total pp → K ⁺Λp cross-section can be explained consistently by the same Λp final-state interaction. Assuming that there is no final-state interaction in the Σ⁰ p channel, as suggested by the available data for the reaction pp → K ⁺Σ⁰ p, we can also reproduce the energy dependence of the Λ/Σ⁰ production ratio and, in particular, the rather large ratio observed near the reaction thresholds. The nominal ratio of the Λ and Σ⁰ production amplitudes squared, i.e. when disregarding the final-state interaction, turns out to be about 3, which is in line with hyperon production data from proton and nuclear targets available at high energies.     

Kinetic energy spectrum and polarization of neutrons from the reaction 12C(p,n)X at 590 MeV

Abstact: The kinetic energy spectrum and the polarization of the PSI neutron beam produced in the reaction ¹²C(p,n)X at 0° with 590 MeV polarized protons were investigated. A strong energy dependence of the neutron beam polarization is observed which was not expected at the time the neutron beam was built. Received: 3 April 1998     

Thermal multifragmentation in p + Au interactions at 2.16, 3.6 and 8.1 GeV incident energies

Multiple emission of intermediate-mass fragments has been studied for the collisions p + Au at 2.16, 3.6 and 8.1 GeV with the FASA setup. The mean IMF multiplicities for events with at least one IMF are equal to 1.7, 1.9 and 2.1 (±0.2) respectively. The multiplicity, charge distributions and kinetic energy spectra of IMF are described in the framework of a intranuclear cascade model followed by the statistical multifragmentation model. However, between the two parts of the calculation the excitation energies and the residual masses and charges are modified to take into account the losses during expansion. The results support a scenario of true thermal multifragmentation of a hot and expanded target spectator. Received: 15 December 1997 / Revised version: 24 April 1998     

New data on the p + N → [Σ0K+] + N reaction at E p= 70 GeV and the search for exotic baryons

New data for the diffractive reaction p+N→ [Σ⁰ K ⁺] +N at E _p= 70 GeV were obtained with partially upgraded SPHINX setup. The data are in a good agreement with the results of our previous study of this reaction. In the mass spectrum M(Σ⁰ K ⁺) a structure at the threshold region with a mass ∼1810 MeV and a distinct X(2000) peak with M= 1989 ± 6 MeV and γ= 91 ± 20 MeV are observed. Unusual features of the massive X(2000) state (narrow decay width, anomalously large branching ratio for the decay channel with strange particle emission) make it a serious candidate for cryptoexotic pentaquark baryon with hidden strangeness |qqqsˉs>. We also present new results on the narrow threshold structure X(1810) with M= 1807 ± 7 MeV and γ= 62 ± 19 MeV which is produced in the region of very small P ² _T < 0.01 GeV². The possibility of the Coulomb production mechanism for X(1810) is discussed. Received: 28 April 1999     

A novel pose and illumination robust face recognition with a single training image per person algorithm

In the real-world application of face recognition system, owing to the difficulties of collecting samples or storage space of systems, only one sample image per person is stored in the system, which is so-called one sample per person problem. Moreover, pose and illumination have impact on recognition performance. We propose a novel pose and illumination robust algorithm for face recognition with a single training image per person to solve the above limitations. Experimental results show that the proposed algorithm is an efficient and practical approach for face recognition.     

K-拟可加模糊数值积分的自连续性

本文在K-拟可加模糊测度空间上建立了K-拟可加模糊数值积分,利用其积分转换定理和诱导算子的性质,将这种积分整体看成可测空间上取值于模糊值和集函数,从而使得这种模糊积分不仅具有自连续性,而且也满足逆自连续性。这些特性能更好地描述模糊值可测函数列和K-拟可加模糊数值积分序列的收敛性。     

The mixed problem for degenerate elliptic equations of second order

The present paper deals with the mixed boundary value problem for elliptic equations with degenerate rank 0. We first give the formulation of the problem and estimates of solutions of the problem, and then prove the existence of solutions of the above problem for elliptic equations by the above estimates and the method of parameter extension. We use the complex method, namely first discuss the corresponding problem for degenerate elliptic complex equations of first order, afterwards discuss the above problem for degenerate elliptic equations of second order.