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computer Modeling in Engineering & Sciences 2024年第5期139卷 1583-1612页

作者： Sergiy Reutskiy Yuhui Zhang Jun Lu Ciren Pubu A.Pidhornyi Institute of Mechanical Engineering Problems of NAS of ukraine Kharkiv61046Ukraine college of Mechanics and Materials Hohai UniversityNanjing211100China Nanjing Hydraulic Research Institute Nanjing210029China Shigatse Everest Urban Investment and Development Group co Ltd.857000China

This paper presents an efficient numerical technique for solving multi-term linear systems of fractional ordinary differential equations(FODEs)which have been widely used in modeling various phenomena in engineering and *** approximate solution of the system is sought in the formof the finite series over the Müntz *** using the collocation procedure in the time interval,one gets the linear algebraic system for the coefficient of the expansion which can be easily solved numerically by a standard *** technique also serves as the basis for solving the time-fractional partial differential equations(PDEs).The modified radial basis functions are used for spatial approximation of the *** collocation in the solution domain transforms the equation into a system of fractional ordinary differential equations similar to the one mentioned *** examples have verified the performance of the proposed novel technique with high accuracy and efficiency.

关键词： System of FODEs numerical solution Müntz polynomial basis time fractional PDE BSM collocation method

Electrocatalytic performance of CNTs/graphene composited rare earth phthalocyanines(M=La,Y,Yb,Sc)

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Journal of Rare Earths 2024年第2期42卷 323-333,I0004页

作者： Tingting Jiang Caixia Ou Luyi Wang Jun Chen Sydorov Dmytro Qian Zhang Jintian Luo Hua Wang Jiangxi Key Laboratory of Power Batteries and Materials Faculty of Materials Metallurgy and ChemistryJiangxi University of Science and TechnologyGanzhou341000China Joint Department of Electrochemical Energy Systems Institute of Bioorganic Chemistry and PetrochemistryNational Academy of Sciences of Ukraine38A VernadskyAveKiev03142Ukraine Guangdong Jiana Energy Technology co. Ltd.Qingyuan511500China

In this study,a class of rare earth composite sandwich phthalocyanines(MPcs,M=La,Y,Yb,Sc) were prepared and compounded with graphene and carbon nanotubes to obtain MPc/Gr and MPc/CNTs *** electrocatalytic behaviors of MPc/Gr and MPc/CNTs electrodes were further *** results show that the central rare earth metal has a large influence on the electrocatalytic *** the MPcs/Gr samples,ScPc with the smallest ionic radius and molecular size can be more uniformly dispersed in graphene,and the hydrogen precipitation overpotential of ScPc/Gr electrode is514 mV,corresponding to a Tafel slope of 148 mV/dec,with better electrocatalytic performance than other rare earth metal *** for the MPc/CNTs composites,LaPc,which has the largest ionic radius and molecular size,is more uniformly dispersed on the surface of CNTs,so that the LaPc/CNT electrode exhibits the best LSV performance with the smallest corresponding Tafel slope(176 mV/dec).The main reason is the different binding modes of MPcs molecules in Gr and *** rare earth phthalocyanine is combined with layered graphene,the smallest size of rare earth phthalocyanine(ScPc)is more easily embedded in the graphene layer,resulting in better homogeneity of the composite,larger effective contact area and better electrocatalytic *** contrast,when rare earth phthalocyanine is bound to carbon nanotubes in a tubular structure,it is mainly bound by attaching to the surface or being entangled by the carbon *** this case,the rare-earth phthalocyanine molecules(LaPc)with larger layer spacing can provide more contact area with CNTs,forming a more uniform and effective composite,which eventually provides more active sites and better electrocatalytic performance.

关键词： Electrocatalysis Rare earth phthalocyanines Graphene(Gr) Carbon nanotubes(CNTs) composite

A Novel Accurate Method forMulti-Term Time-Fractional Nonlinear Diffusion Equations in Arbitrary Domains

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computer Modeling in Engineering & Sciences 2024年第2期138卷 1521-1548页

作者： Tao Hu Cheng Huang Sergiy Reutskiy Jun Lu Ji Lin Ningbo Yongxin Engineering consulting co. Ltd.Ningbo315042China Taizhou HuanfengWater conservancy Engineering co. Ltd.Taizhou318050China A.Pidhornyi Institute of Mechanical Engineering Problems National Academy of Sciences of UkraineKharkiv61046Ukraine Material and Structure Department Nanjing Hydraulic Research InstituteNanjing210029China college of Mechanics and Materials Hohai UniversityNanjing211100China

Anovel accuratemethod is proposed to solve a broad variety of linear and nonlinear(1+1)-dimensional and(2+1)-dimensional multi-term time-fractional partial differential equations with spatial operators of anisotropic ***(1+1)-dimensional problems,analytical solutions that satisfy the boundary requirements are *** solutions are numerically calculated using the trigonometric basis approximation for(2+1)-dimensional *** the aid of these analytical or numerical approximations,the original problems can be converted into the fractional ordinary differential equations,and solutions to the fractional ordinary differential equations are approximated by modified radial basis functions with time-dependent *** efficient backward substitution strategy that was previously provided for a single fractional ordinary differential equation is then used to solve the corresponding *** straightforward quasilinearization technique is applied to handle nonlinear *** experiments demonstrate the suggested algorithm’s superior accuracy and efficiency.

关键词： Müntz polynomial basis backward substitutionmethod collocationmethod meshlessmethod fractional equation

Variations of Atmospheric ELF/VLF Radio Noise Due to Seismogenic Modifications in Tropospheric conductivity

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Open Journal of Earthquake Research 2024年第2期13卷 113-132页

作者： Masashi Hayakawa Alexander P. Nickolaenko Hayakawa Institute of Seismo Electromagnetics Co. Ltd. (Hi-SEM) UEC Alliance Center #521 Tokyo Japan The University of Electro-communications (UEC) Advanced Wireless & Communications Research Center (AWCC) Chofu-shi Tokyo O.Ya. Usikov Institute for Radiophysics and Electronics National Academy of Sciences of the Ukraine Kharkov Ukraine

We suggest a possible explanation of the influence of pre-seismic activity on the registration rate of natural ELF(extremely low frequency)/VLF(very low frequency) pulses and the changes of their characteristics. The main idea is as follows. The distribution of the electric field around a thundercloud depends on the conductivity profile of the atmosphere. Quasi-static electric fields of a thundercloud decrease in those tropospheric regions where an increase of air conductivity is generated by pre-seismic activities due to emanation of radioactive gas and water into the lower atmosphere. The electric field becomes reduced in the lower troposphere, and the probability decreases of the cloud-to-ground (CG) strokes in such “contaminated” areas. Simultaneously, the electric field grows inside and above the thunderclouds, and hence, we anticipate a growth in the number of horizontal and tilted inter-cloud (or intra-cloud) (both termed as IC discharges) strokes. Spatial orientation of lightning strokes reduces vertical projection of their individual amplitudes, while the rate (median number strokes per a unit time) of discharges grows. We demonstrate that channel tilt of strokes modifies the spectral content of ELF/VLF radio noise and changes the rate of detected pulses during the earthquake preparation phase.

关键词： ELF/VLF Radio Noise Earthquake Precursor Pre-Seismic Modification conductivity Anomaly in the Lower Atmosphere Radioactive Radon Gases CG Lightning Discharges IC Discharges Cloud-to-Ionosphere Discharge

Empirical model of correction for zenith tropospheric delay

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Journal of Measurement Science and Instrumentation 2014年第4期5卷 20-28页

作者： V F Kravchenko V I Lutsenko I V Lutsenko D O Popov A G Laush V N Gudkov Kotel'nikov Institute of Radio Engineering and Electronics Russian Academy of Sciences Usikov Institute of Radiophysics and Electronics of National Academy of Sciences of ukraine co ltd. navis-ukraine

The paper considers the possibility of correction of zenith tropospheric delays, and calculates it with the standard model, which takes into account the values of the refractive index of the troposphere at the time of measurement. Based on the experimental research, this empirical model of correction for zenith tropospheric delays can reduce the measurement er- ror of coordinates to about 30 % and altitude to about 40 %.

关键词： zenith tropospheric delays satellite navigation signal global positioning system (GPS) global navigation satel-lite system (GLONASS)

Design of the Airbag Inflation System Applicable to conventional and Autonomous Vehicles

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Automotive Innovation 2021年第4期4卷 390-399页

作者： Nina F.Yurchenko David S.Breed Shaowei Zhang Laboratory for Advanced Aerodynamics and Interdisciplinary Research Institute of HydromechanicsNational Academy of Sciences of Ukraine8/4 Zheliabov St.Kyiv 03680Ukraine Automotive Technologies International Inc.USA800 West AveUnit 545Miami BeachFL 33139USA Shanghai East Joylong Motor Airbag co. Ltd.219#Qingda Road Pudong DistrictShanghaiChina

The emergency transformation of various aspects of life and business these days requires prompt evaluation of autonomous *** of the primary reassessments deals with the applicability of the vehicle passive safety system to the protec-tion of arbitrarily positioned *** mitigate possible risks caused by the simultaneous deployment of several big airbags,a new principle of their operation is ***,the aspirated inflator for a driver airbag is developed that can provide 50L-airbag inflation within 30-40 *** a result,about 3/4 of the air is to be entrained into an airbag from the vehicle *** process is initiated by a supersonic pulse jet(1/3 air volume)generated *** the Prandtl-Meyer problem formulation enables guiding linear and angular dimensions of the essential parts of the ***,a family of experimental models of varied geometry is fabricated and tested to determine their operational effectiveness in a range of motive pressure within~3-7 *** are performed on a specially designed facility equipped with compressed-air tanks and a high-speed valve to mimic the inflator operation with the pyrotechnic gas *** aspirated inflator operability is characterized using multivariate measurements of pressure fields,high-speed video-recording of the airbag inflation process,and evaluation of aspiration(entrainment)*** average volume aspiration ratio measured at 300 K is found to reach 2.8 and it’s expected to almost double at 1200 K.

关键词： Novel airbag system Aspirated inflator Air entrainment effectiveness Experimental investigations

Three-point method of differential correction of coordinates and pseudo-range in GPS

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Journal of Measurement Science and Instrumentation 2014年第1期5卷 41-45页

作者： V F Kravchenko A G Laush V I Lutsenko I V Lutsenko D O Popov 王建园 Kotelnikov Institute of Radio Engineering and Electronics of Russian Academy of Sciences co ltd.navis-ukraine Usikov Institute of Radiophysics and Electronics of National Academy of Sciences of Ukraine 南京航空航天大学(NUAA) 南京210016

This paper presents the interpolation method of generating the differential correction to coordinates and *** a consequence,to improve the quality and stability of the generated correction of amendments,it is advisable to use a system of three reference *** demonstrates the advantages of the interpolation method in comparison with the standard method of differential correction.

关键词： refraction troposphere differential correction satellite navigation systems

Formation of Ionospheric Precursors of Earthquakes—Probable Mechanism and Its Substantiation

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Open Journal of Earthquake Research 2020年第2期9卷 142-169页

作者： Georgii Lizunov Tatiana Skorokhod Masashi Hayakawa Valery Korepanov Space Research Institute Kyiv Ukraine Hayakawa Institute of Seismo Electromagnetics co. Ltd. Tokyo Japan Lviv Center of Institute for Space Research Lviv Ukraine

The purpose of this article is to attract the attention of the scientific community to atmospheric gravity waves (GWs) as the most likely mechanism for the transfer of energy from the surface layers of the atmosphere to space heights and describe the channel of seismic-ionospheric relations formed in this way. The article begins with a description and critical comparison of several basic mechanisms of action on the ionosphere from below: the propagation of electromagnetic radiation;the closure of the atmospheric currents through the ionosphere;the penetration of waves throughout the neutral atmosphere. A further part of the article is devoted to the analysis of theoretical and experimental information relating to the actual GWs. Simple analytical expressions are written that allow one to calculate the parameters of GWs in specific experimental situations. Specificity of GW dispersion properties and features of their propagation are analyzed on this mathematical basis, processes of amplitude amplification and dissipation of GWs with height are investigated, the mechanism of generation of ionosphere-magnetosphere current systems is described and their quantitative characteristics are determined. The experimental part presents an analysis of GWs global distribution in the thermosphere derived from the data of the instrument NACS (Neutral Atmosphere composition Spectrometer) onboard the satellite DE-2 (NASA, 1981-1983). The statistical association of registered ionospheric disturbances with earthquakes is demonstrated. The results of DE-2 data processing are backed up by comparison with data from the DEMETER satellite (CNES, 2005-2010) whose purpose was to study the ionospheric effects of earthquakes. Specific features of GWs that characterize these waves as a factor of influence on the ionosphere from below are indicated.

关键词： Atmospheric Gravity Waves Seismic-Ionospheric coupling Thermosphere

Take Quality as Life,Seek Development through Honesty

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China's Foreign Trade 2006年第24期 50-53页

作者： Yang Xiaoyi Heilongjiang Shengxing Group co. Ltd.

Heilongjiang Shengxing Group co., ltd. is a comprehensive private enterprise, with me main business in wood processing, and integrating science, industry, trade, agriculture and .forestry. Harbin Shengxing Economic ＆ Technological Development co., ltd., HarbinBin county, Shengxing Furniture Manufacturing co., ltd., Harbin Shengxing Biological Engineering co., ltd. are the member enterprises.

关键词：黑龙江木材加工企业产品结构技术创新

Whispering Gallery Modes Formed by Scattering of an Electromagnetic Plane Wave by Two Cylinders

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Journal of Applied Mathematics and Physics 2017年第4期5卷 785-791页

作者： Arnold Abramov Yutao Yue Chunlin Ji Ruopeng Liu Xue Li Juehui Zhou Alexander Kostikov Kuang-Chi Institute of Advanced Technology Shenzhen China Shenzhen Kuang-Chi Innovative Technology co. ltd. Shenzhen China Donbass State Engineering Academy Kramatorsk Ukraine

We report the effect of scattering of electromagnetic plane waves by two cylinders on whispering gallery mode (WGM) formation in a cylinder. WGM can occur because of the presence of additional cylinder scatterers at specific location, while WGMs can only form in a single cylinder for specific cylinder radius and/or wavelength values, the matching accuracy required would be much greater than that required in our model for the additional cylinders locations. Analysis of the general solution to the problem showed that the effect can be explained by the interference of waves scattered by additional cylinders and incident on the main cylinder.

关键词： Scattering Wave Cylinder WGM