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New Method in Calculating the Trajectory of Sound Waves at Stratified Ocean

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Open Journal of Acoustics 2016年第2期6卷 13-21页

作者： V. P. Ivanov G. K. ivanova Institute of Applied Physics Russian Academy of Sciences Nizhny Novgorod Russia

There is a new method of calculating the trajectory of sound waves (rays) in layered stratified speed of sound in ocean without dispersion. A sound wave in the fluid is considered as a vector. The amplitudes occurring at the boundary layers of the reflected and refracted waves are calculated according to the law of addition of vectors and using the law of conservation of energy, as well as the laws that determine the angles of reflection and refraction. It is shown that in calculating the trajectories, the reflected wave must be taken into account. The reflecting wave’s value may be about 1 at certain angles of the initial wave output from the sours. Reflecting wave forms the so-called water rays, which do not touch the bottom and the surface of the ocean. The conditions of occurrence of the water rays are following. The sum of the angles of the incident and refracted waves (rays) should be a right angle, and the tangent of the angle of inclination of the incident wave is equal to the refractive index. Under these conditions, the refracted wave amplitude vanishes. All sound energy is converted into the reflected beam, and total internal reflection occurs. In this paper, the calculation of the amplitudes and beam trajectories is conducted for the canonical type of waveguide, in which the speed of sound is asymmetric parabola. The sound source is placed at the depth of the center of the parabola. Total internal reflection occurs in a narrow range of angles of exit beams from the source 43° - 45°. Within this range of angles, the water rays form and not touch the bottom and surface of ocean. Outside this range, the bulk of the beam spreads, touching the bottom and the surface of the ocean. When exit corners, equal and greater than 77°, at some distance the beam becomes horizontal and extends along the layer, without leaving it. Calculation of the wave amplitudes excludes absorption factor. Note that the formula for amplitudes of the sound waves applies to light waves.

关键词： Sound Wave Rays Water Ray Trajectory Liquid Space

Simulation Approach to Risk Quantification While Resources Estimation on Seismic and Log Data

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岩性油气藏 2010年第F7期22卷 109-112页

作者： A. G. Averbukh N. L. ivanova Central Geophisical Expedition Russia

Some Aspects of Ray Representation Running Sound Waves in Liquid Spaces

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Open Journal of Acoustics 2013年第1期3卷 7-13页

作者： V. P. Ivanov G. K. ivanova Institute of Applied Physics Russian Academy of Sciences Nizhny Novgorod Russia

Work is devoted to the analysis of errors meeting in literature in treatment of a spatial part of a phase of running sound waves. In some cases, it is not taken into consideration that this part of a phase is formed by scalar product of vectors which does not depend on a choice of system of co-ordinates. Taking into account the necessary corrections in record of a phase of plane waves, it is shown that the decision of the homogeneous wave equation in the form of “belated” potentials is simultaneously and the decision of the equations of movement of a liquid, and “outstripped” potentials does not satisfy them. The analysis of coefficients of reflection and passage of running waves in non-uniform space is carried out. It is shown that on boundary of spaces with different sound speeds, a turning point of a sound wave is the point of full internal reflection. The way of calculation of coefficients of reflection and passage is offered by consideration of all three waves on boundary of spaces as vectors with the set directions and amplitude of a falling wave. Calculation of coefficients of reflection and passage of a sound wave in a wave-guide of canonical type along the chosen trajectory by two methods—under traditional formulas and a vector method is carried out. Results of calculation practically coincide.

关键词： Sound Running Waves Wave Equation Reflection Passage Liquid Space Wave-Guide Rays

To the Question of Sound Waves Propagation in Liquid

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Open Journal of Acoustics 2015年第3期5卷 112-121页

作者： V. P. Ivanov G. K. ivanova Institute of Applied Physics Russian Academy of Sciences Nizhny Novgorod Russia

This paper is proposed to consider the propagation of sound waves in the liquid as a result of special deformation of the medium. Mechanical vibrations of the membrane, (diaphragm) creating a sound wave, transfer from layer to layer in medium without causing synchronous oscillations of the fluid particles. It can be assumed that the deformation of the liquid is similar to the driving force (pressure) in the direction perpendicular to the plane of the vibrating membrane. Usually, the running wave functions are used to describe the sound waves, but they do not contain the direction of propagation. It is proposed to consider that the amplitude of the wave is a vector coinciding with the vector tangent to the path of the wave. This would allow for a change of direction of propagation without changing its phase, in which the direction of wave is not present. It proposed a method of calculating a vector of amplitudes of the reflected and transmitted sound waves based on the laws of conservation of impulse and energy of the waves and the boundary conditions defined by Snell’s law. It is shown that one of the two solutions of the wave equation does not apply to real physical process of sound wave’s propagation in the liquid.

关键词： Sound Running Waves Wave Equation Reflection Passage Liquid Space

A New Concept of Calculation Coefficietns of Reflection and Passage Sound Waves on the Boundary of Liquid Spaces

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Open Journal of Acoustics 2013年第3期3卷 72-79页

作者： V. P. Ivanov G. K. ivanova Institute of Applied Physics Russian Academy of Sciences Nizhny Novgorod Russia

It is consider that, from the standpoint of the law of conservation of energy, the process of converting sound wave falls on the boundary between two spaces in two, leaving the boundary, reflected and passage. It is assumed that the simultaneous presence of three waves is impossible, and that the process of converting one wave in two waves occurs instantaneously. Based on this concept, enter the following boundary conditions for the calculation of amplitudes (coefficients) of the reflected and passage waves. The initial phases of the reflected and passage waves coincide with the phase of the falling wave. The energy of the falling wave is equal to the sum of the energies of the reflected and passage waves. The normal component velocity amplitude of the particle of the liquid under the influence of the falling wave is equal to the sum of the normal component of particle velocity amplitudes of the reflected and passage waves. It was found that the character of dependence of the reflection coefficient on the angle of departure of the initial wave is the same as in the traditional formulas, but the coefficient of passage does not exceed unity. Calculations of reflection and passage coefficients for different values of the refractive coefficient at the boundary between two homogeneous spaces as well as the canonical form of the waveguide, wherein the speed of sound which is minimum at predetermined depth is carried out.

关键词： Sound Running Waves Trajectory Phase Reflection Passage Liquid Space Wave-Guide

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俄罗斯帝国汉语教学历史及其当代启示

俄罗斯帝国汉语教学历史及其当代启示

作者： ivanova Olga（伊瓦诺娃奥丽加）青岛大学

学位级别：硕士

俄罗斯汉语教学已经有300多年历史,在其发展进程中,俄罗斯帝国汉语教学的发展起到了举足轻重的作用。虽然俄罗斯帝国的汉语教学遇到了很多障碍,但是取得了良好的进展。本文着眼于俄罗斯帝国汉语教学的发展过程及其对当代俄罗斯汉语教学... 详细信息

俄罗斯汉语教学已经有300多年历史,在其发展进程中,俄罗斯帝国汉语教学的发展起到了举足轻重的作用。虽然俄罗斯帝国的汉语教学遇到了很多障碍,但是取得了良好的进展。本文着眼于俄罗斯帝国汉语教学的发展过程及其对当代俄罗斯汉语教学的启示,对俄罗斯帝国汉语教学的历史进行研究并结合当下俄罗斯汉语教学现状加以分析,旨在为当代俄罗斯汉语教学提供启示。到17世纪末,由于中国和俄罗斯还没有往来,俄罗斯人没有学习汉语。随着中国和俄罗斯面积的扩大,汉语教学的问题开始变得越来越紧迫。到19世纪,18世纪初建立的东正教驻北京传道团是俄罗斯第一个和主要的汉语教学的中心,其学生是俄罗斯汉语教学的组织者。19世纪上半叶,俄罗斯帝国汉语教学得到迅速的发展,俄罗斯形成三个汉语教学的中心。19世纪下半叶,圣彼得堡大学、培训班、专门翻译学校对汉语教学的发展做出了很大贡献,但是19世纪末,俄罗斯的汉语教学面临着教学危机。20世纪初,俄罗斯汉语教学不但克服教学危机,而且提高了教学和研究的水平。俄罗斯帝国的汉语学家奠定了当代俄罗斯汉语教学的基础,当时积累的知识和经验有助于确定俄罗斯现代汉语教学的方向和形式。俄罗斯帝国汉语教学的成功经验对当代俄罗斯的影响很深,目前,当代俄罗斯汉语教学仍沿用俄罗斯帝国高等学校制定的汉语教学安排、方法和原则。俄罗斯帝国汉语教学面临就业、教材、教学安排等问题和经受因资金支持不够、年轻教师和研究者不够、教材和教学水平不够好而发生教学危机,这种经验值得我们深入研究,研究俄罗斯帝国应对汉语教学危机的经验,有助于我们更好地解决当代俄罗斯汉语教学面临的问题。

关键词：俄罗斯帝国汉语教学历史当代启示

Indoor Radon Concentrations of School Buildings in Varna District, Bulgaria

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Journal of Environmental Science and Engineering(B) 2022年第2期11卷 43-48页

作者： Desislava Djunakova Bistra Kunovska Jana Djounova Kremena ivanova Zdenka Stojanovska National Centre of Radiobiology and Radiation Protection Sofia 1606Bulgaria Faculty of Medical Sciences Goce Delcev UniversityStip 2000Republic of North Macedonia

Radon is a radioactive gas that is naturally produced by the breakdown of uranium in soil,rock and *** International Commission on Radiological Protection(ICRP)and World Health Organization(WHO)requirements include controlling indoor radon exposure and settings of a reference level for the annual average activity concentration of up to 300 Bq/m3 for dwellings and public *** measurements in school buildings have long been carried out in many *** measurements in schools in Bulgaria have started and are *** study concerns the measurements of radon concentration(CRn)in all state school buildings in one of the Black Sea regions,Varna district,and the analysis of indoor *** survey of 1,185 premises of 107 schools was conducted from December 2019/January 2020 to March/May 2020 using a passive *** AM(Arithmetic Mean)of CRn in the premises of the studied schools on the territory of Varna district is 130 Bq/m^(3),and the geometric mean is 97 Bq/m^(3).The number of premises exceeding the national reference level of 300 Bq/m^(3) is 72 located in 38 schools(about 36% of schools).A statistically significant difference(KW(Kruskal-Wallis),p<0.0001)was found between the radon data,grouped by ***,the radon data were classified into two groups based on municipality location:on the Black Sea coast and *** located near the sea have a higher value of *** order to more accurately assess the exposure of pupils and teachers,the results are divided into four groups,depending on the type of use of the premises and the floor on which they are *** highest CRn value was found in the study rooms used for specialized education such as physics,chemistry,music etc.(AM=155 Bq/m3),which can be explained by their smaller size and less frequent use.A statistically significant difference(KW,p<0.0001)was found,which means that the radon exposure in the examined rooms depends on the type of use.T

关键词： Radon schools measurement classrooms Bulgaria

INVESTIGATION PERIODIC MULTILAYERED METAMATERIAL STRUCTURES BY THE MODERNISED TRANSLATION MATRIX METHOD

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INVESTIGATION PERIODIC MULTILAYERED METAMATERIAL STRUCTURES ...

Religious Buildings in the Spatial Pattern of a Provincial Town of the ⅩⅨ Century Case Study: the Towns of the Southern Russia

第六届无线与电波传播国际会议（ISAPE）

作者： Inna L. ivanova Vlad A.Nikitin Radiophisics Department Dnepropetrovsk National University Radiophisics Department Dnepropetrovsk National University

An inhomogeneous isotropic periodic medium with negative parameters is studied. Two similar approaches based on translation matrix method are considered. Comparison of these is carried out.

关键词： INVESTIGATION PERIODIC MULTILAYERED METAMATERIAL STRUCTURES BY THE MODERNISED TRANSLATION MATRIX METHOD

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Religious Buildings in the Spatial Pattern of a Provincial T...