Electrical passivation of the silicon surface by organic monolayers of 1-octadecene

The electrical properties of structures consisting of a monolayer of 1-octadecene deposited on the Si surface are investigated depending on the method of passivation of the surface prior to the deposition of the film (hydrogen and ion passivation) and the intensity of illumination which activates the addition reaction of molecules of 1-octadecene to the Si atoms. The monolayer of 1-octadecene on the Si surface is stable and provides the chemical passivation of the surface. Two types of traps are found, namely, traps for holes and electrons, whose density can be varied during deposition of the monolayer by the choice of intensity of illumination and by the method of passivation of the surface. In the case of a low level of illumination and/or the use of the iodine passivation of the surface, the electron traps prevail, and, in the case of high intensity of illumination and/or hydrogen passivation of the surface, the hole traps prevail. It is shown that the use of these films provides conductivity in thin near-surface layers of Si due to providing the mode of flat bands or accumulation of carriers near the surface.     

Estimation of the number of orthogonal signals with unknown parameters

Algorithms for estimation of the number of signals with unknown amplitudes and several non-energy parameters are synthesized on the basis of the modified maximum likelihood method. Asymptotic values of the probabilities of the error in estimation of the signal number are determined. The effect of a reduced volume of the a priori domain of possible values and the dimensionality of the vector of unknown non-energy parameters on the quality of operation of the algorithms for estimation of the number of signals is investigated.     

一种新的变步长LMS算法在通信对消技术的应用

本文通过分析几种变步长LMS算法,结合VSS-NLMS算发和NLMS算法的优点,采用符号函数降低原有算法的计算复杂度,对变步长参数进行调整,提出了一种改进的变步长LMS算法,通过仿真验证,新提出的算法在收敛速度和稳态误差上也有一定优点,具有工程实际意义。     

Effect of sodium selenite on the activity of antioxidant enzymes (superoxide dismutase, glutathione peroxidase) during hepatocarcinogenesis

Influence of sodium selenite on functioning of the systems of intracellular generation and detoxication of active oxygen compounds in hepatocarcinogenesis induced by diethylnitrosamine has been studied in experiments on rats. It has been shown that the duration of latent period initiated by ions of Fe2+ chemiluminescence of homogenate of the liver rather objectively reflects the state of the functioning of the systems in charge of the formation and utilization of free radicals of oxygen in a cell. It is supposed that one of the mechanisms of anticarcinogenic action of selenium is connected with its antioxidant functions in the organism and consists in the increase of the activity of superoxide dismutation and selenium-dependent glutathione peroxidases, providing a reliable level of enzymatic protection of normal cells from disturbing action of "active oxygen".     

Nonequivalence of biparticle and multiparticle quantum entanglements

The problem of the impossibility of completely describing the quantum entanglement of a system of many particles only with the biparticle entanglement of the constituent subsystems is treated. The numerical procedure of the selection of a contrary instance and the results of the procedure are described. It is also shown that the measure of the entanglement of pure states on the basis of the minimization of the entropy of measurements is essentially a multiparticle measure; i.e., this measure of entanglement cannot be expressed in terms of the Schmidt coefficients.     

Statistical characteristics of chaoticity and incomplete chaoticity of irregular oscillations generated by a strongly nonlinear autonomous system with two degrees of freedom

The notion of the interval of nonergodicity as one of the statistical characteristics for time realizations of an irregular process is introduced. A method for determination of this factor based from the analysis of autocorrelation functions of truncated realizations is developed. The chaoticity of irregular oscillations in a strongly nonlinear autonomous system with two degrees of freedom is proved using the criterion of decomposition of time correlations. The statistical indication of the existence of incomplete chaoticity of oscillations in the case of incomplete decomposition of correlations is formulated. Conditions of weak distortions of the energy spectrum for truncated realizations are determined. Probability distribution functions for the characteristics of an irregular time process in the studied system are considered.     

A method of analysis of periodic processes in nonautonomous discrete-time systems with quantization

A method of analysis of stationary processes in systems with an arbitrary number of quantization levels in the presence of periodic external signals is proposed. The method is based on the representation of stationary oscillations in the form of an invariant set of nonlinear discrete point mappings. The spectral composition of the response of a system with an arbitrary period coupled with the discretization period through a rational relationship is calculated with the use of the discrete Fourier transform. The discrete Fourier transform is applied also to calculate nonlinear distortions. It is suggested to use the dependence of the ratio of the first-harmonic amplitude of the system’s steady-state response to the amplitude of the input-signal harmonic on the frequency of the input harmonic signal as the amplitude-frequency characteristic of a nonlinear system. In addition, it is suggested to use the dependence of the difference between the argument of the first harmonic of the system’s response and the initial phase of the input signal on the frequency of the input harmonic signal as the phase-frequency characteristic of the system. The usage of the method is illustrated by its application for the analysis of processes in first-and second-order circuits.     

Modeling of wideband slow-wave structures of coupled-cavities-chain type by the impedance design of experiments

The results of investigation on the possibility of a substantial extension of the operating-frequency band of a slow-wave structure of coupled-cavities-chain type are presented for the case of a small variation in the slowing factor of the phase velocity of a wave, including, in the case of convergence of the cavity and slot passbands. The investigation is performed with the use of regression models for electrodynamic characteristics of the slowing structure that are constructed on the basis of the results obtained by the impedance design of experiments. Variants of wideband chains of coupled cavities with differences in the phase-velocity slowing factor of ±3% and the operating width of the cavity passband of up to 35%, as well as structures with merging of the cavity and slot passbands and a resulting passband of up to 70% and a coupling impedance of 18–0.4 Ω, are obtained.     

Bayesian estimate of the doppler frequency shift with reduction of the data dimensionality

The paper considers the possibility of reducing the amount of calculations of the Bayesian estimate of the Doppler frequency shift and the initial phase of a quasi-deterministic signal observed in the presence of white-noise distortions due to introduction of the stage of reduction of the dimensionality of the observed data. The minimization of the loss of the Fisher information on the estimated parameter is used to control the correctness of the dimensionality reduction procedure; the estimation accuracy depends on this procedure. The computer simulation using test signals proves the possibility of a considerable reduction in the amount of calculations upon realization of Bayesian procedures for the same estimation accuracy.     

基于物联网的图书馆管理系统

针对物联网的基本概念、起源、发展以及物联网关键技术,针对图书馆借书流程、图书快速定位、图书安全等问题与RFID技术的应用进行设计。通过介绍智能图书馆对于物联网技术的应用,提出智能图书馆的智能化和便捷化,同时也提出了发展物联网的重要意义,通过对只能图书馆的设计,让人们真切感受到物联网对人们生活的提升。     

A model of nonlinear optical transmittance for insulator nanocomposites

A theoretical model of the laser radiation transmittance of insulator nanocomposites containing low concentrations of nanoparticles is proposed. It is shown that the basic mechanisms of low-threshold effects of nonlinear absorption and scattering of laser radiation are, first, the induction of electric dipole moments of nanoparticles in the external field and, second, the orientation of nanoparticles along the polarization direction of this field. The behavior of the transmittance in the vicinity of the central region of a separate absorption band and the dependence of the depth of this band in the transmittance spectrum on the external radiation intensity are considered.     

Numerical simulation of two-particle resonant scattering with the formation of a molecular ion

Using numerical simulation, the process of formation of a positively charged molecular ion during resonant scattering of a positive ion by the intrinsic atom is considered. The method of calculation of physical characteristics of the process based on the notion of evolution of classic Ψ function of the system as classic evolution of all pairs of initial particles is suggested. Integrated characteristics of model processes of formation of the molecular ion are calculated. The probabilistic estimates of formation of the positive molecular ion of hydrogen are obtained.     

A system for optimization of the output characteristics of electronic components

A general approach to solution of optimization problems for systems with a large number of degrees of freedom and a set of software objects with open interface are developed and are used for construction of the architecture of a software system for solution of a broad range of optimization problem via the search for the extrema of an objective function with the help of genetic algorithms. Genetic algorithms are used for both optimization of the system itself and selection of the optimum parameters of the genetic algorithm. The software system was evaluated with a large set of problems related to calculation of the topology of surface-acoustic-wave frequency selective filters. The system architecture is built in accordance with the basic principles of the service-oriented architecture.     

Approximate 3D model of electromagnetic modes in waveguide cross-shaped junctions with dielectric filling

Athree-dimensional electrodynamic model of hybrid electromagnetic modes in a waveguide junction of cylindrical and rectangular waveguides with dielectric filling of a cylindrical waveguide is proposed in this study. To solve the vector problem, the mode matching technique (MMT) is applied with the separation of the common waveguide junction region and the representation of the field in this region in the form of superposition of the fields of the partial eigenwaves of waveguides. Classification of eigenmodes is carried out: intrinsic resonances of junction based on transcendental modes and resonances of a waveguide-dielectric type. The investigated structure can be used for measuring the electrical parameters of dielectric samples of both cylindrical and rectangular cross-section shape. Since the spectral characteristics of the junction are determined mainly by the size of the central coupling region of the waveguides and the electrical parameters of the dielectric in the junction, the measurements are of a local nature.     

无人作战模拟仿真中的VV＆A

根据无人作战模拟研究、开发过程中分队级作战单位建模与仿真环节上所存在的VV&A问题,从军事建模的过程与军事工程技术的角度出发,将一般仿真过程中的VV&A技术与军事作战模拟的特点以及无人作战模拟的特殊性三者有机的结合在一起,深入的探讨了在无人作战模拟仿真过程中VV&A问题的解决办法以及实现过程。通过对无人作战模拟仿真中VV&A的研究与解决,为今后的作战模拟,特别是无人作战模拟中如何解决建模及仿真过程中所存在的类似问题提出了一套系统的、科学的实现办法,具有一定的理论及实践意义。对于我军无人作战研究的深入开展以及跨越式发展具有一定的参考价值。     

Radiation from a Plasma Layer with a Strong Longitudinal Irregularity

The efficiency of conversion of the energy of a surface wave into radiation at longitudinal irregularities of a planar plasma layer is studied. The analysis is performed by the spectral expansion of the field in a complete set of surface and pseudosurface waves. The system of integro-differential equations for the coefficients of expansion that determine the amplitudes of the transmitted, reflected, and scattered waves as well as the radiation pattern is solved in the case of a rapid change in the plasma density. The coefficients of transformation of energy into the energy of radiation as functions of the gradient of the plasma density for different values of the electrical length of the region of plasma irregularity and the electric thickness of the plasma layer are found. Examples are demonstrated when the fraction of the energy of the surface wave transformed into radiation reaches 60–70%. Radiation patterns that proved to be highly directional and having one lobe with the maximum at an angle of a few degrees to the direction of propagation of the surface wave are calculated.     

左手材料的色散和等倾干涉

研究了左手材料棱镜的色散特性和左手材料平行平板的等倾干涉特性。对于左手材料棱镜而言,其色散时出射光偏离原来的传播方向与右手材料棱镜的色散规律恰好相反,且对于同一种单色光而言,当入射角相同时,左手材料棱镜的色散偏向角大于右手材料棱镜的色散偏向角。在研究左手材料平行平板的等倾干涉特性时,推导了反射光和透射光焦平面上的光强分布公式,分析了等倾干涉条纹的级数与亮、暗条纹的关系,讨论了光程差的影响因素及影响规律,推导了存在半波损失情况下的等倾圆环的亮环半径公式和暗环宽度公式。研究发现:对于左手材料平行平板的等倾干涉条纹而言,等倾干涉圆环中心处的干涉级数较小;偏离圆环中心越远,干涉条纹的级数越大。这一规律和右手材料平行平板的等倾干涉条纹规律不同。