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Research on Strategy for Russian Company "Business Lines" Entering Chinese Market

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Research on Strategy for Russian Company "Business Lines" En...

作者： Kuznetsov ivan 东北大学

学位级别：硕士

A Numerical Investigation of the Effect of Boundary Conditions on Acoustic Pressure Distribution in a Sonochemical Reactor Chamber

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Fluid Dynamics & Materials Processing 2024年第6期20卷 1425-1439页

作者： ivan Sboev Tatyana Lyubimova Konstantin Rybkin Michael Kuchinskiy UEC-Aviadvigatel 93 Komsomolsky ProspectPerm614990Russia Laboratory of Computing Hydrodynamic Institute of Continuous Media Mechanics UB RASPerm614013Russia Laboratory of Interfacial Hydrodynamic Perm State UniversityPerm614068Russia

The intensification of physicochemical processes in the sonochemical reactor chamber is widely used in problems of synthesis,extraction and *** of the most important mechanisms at play in such processes is the acoustic cavitation due to the non-uniform distribution of acoustic pressure in the *** has a strong impact on the surface degradation *** this work,a numerical calculation of the acoustic pressure distribution inside the reactor chamber was performed using COMSOL *** numerical results have revealed the dependence of the structure of the acoustic pressure field on the boundary conditions for various thicknesses of the piezoelectric *** particular,the amplitude of the acoustic pressure is minimal in the case of absorbing boundaries,and the attenuation becomes more significant as the thickness of the piezoelectric transducer *** addition,reflective boundaries play a significant role in the formation and distribution of zones of maximum cavitation activity.

关键词： Ultrasound numerical simulation acoustic pressure field cavitation erosion foil test

Running-in friction of hip joint replacements can be significantly reduced:The effect of surface-textured acetabular cup

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Friction 2020年第6期8卷 1137-1152页

作者： David NECAS Hatsuhiko USAMI Tatsuya NIIMI Yoshinori SAWAE ivan KRUPKA Martin HARTL Faculty of Mechanical Engineering Brno University of TechnologyBrno 61669Czech Republic Faculty of Science and Technology Meijo UniversityNagoya 468-8502Japan Kanefusa Corporation Nagoya 480-0192Japan Faculty of Engineering Kyushu UniversityFukuoka 819-0395Japan

Hip joint replacements represent the most effective way of treatment for patients suffering from joint *** the rapid improvement of implant materials over the last few decades,limited longevity associated with wear-related complications persists as the main ***,improved tribological perfor-mance is required in order to extend the service life of *** effect of surface texturing of ultra-high molecular weight polyethylene(UHMWPE)acetabular cup was investigated in the present *** tilling method was utilized for manufacturing the dimples with controlled diameter and depths on the contact surface of the *** experiments with four commercial femoral components and two model lubricants were *** main attention was paid to a coefficient of friction considering the differences between the original and the dimpled *** showed remarkable lowering of friction,in *** on the simulated human synovial fluid,friction was reduced by 40%(alumina ceramic),38.8%(zirconia toughened ceramic),25.5%(metal),and 9.9%(oxinium).In addition,the dimples helped to keep the friction stable without *** conclude,the paper brings a new insight into frictional behaviour of the hip replacements during running-in phase which is essential for overall implant *** is believed that proper surface texturing may rapidly improve the life quality of millions of patients and may lead to considerable financial savings.

关键词： hip joint replacement friction texturing dimple longevity

Influence of Methane-Hydrogen Mixture Characteristics on Compressor Vibrations

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Fluid Dynamics & Materials Processing 2024年第5期20卷 1031-1043页

作者： Vladimir Ya.Modorskii ivan E.Cherepanov High Performance Computing Center Perm National Research Polytechnic UniversityPerm614990Russia

A transition to clean hydrogen energy will not be possible until the issues related to its production, transportation,storage, etc., are adequately resolved. Currently, however, it is possible to use methane-hydrogen *** gas can be transported using a pipeline system with the required pressure being maintained by gascompression stations. This method, however, is affected by some problems too. Compressors emergency stopscan be induced by vibrations because in some cases, mechanical methods are not able to reduce the vibrationamplitude. As an example, it is known that a gas-dynamic flow effect in labyrinth seals can lead to increasedvibrations. This paper presents the numerical simulation of rotor oscillations taking into account a gas-dynamicload. The influence of a transported mixture on the oscillatory process is investigated. Mixtures consisting ofmethane and hydrogen in various proportions and an air mixture are considered. The results are discussed forvarious operating pressures and include the rotor motion trajectories and oscillation frequency spectra obtainednumerically. It is shown that the gas mixture composition has a significant effect on the oscillations and theiroccurrence. Hydrogen as a working fluid reduces the vibration amplitude. Operating a compressor with hydrogenleads to a decrease in the resonant frequency, bringing it closer to the operating one. However, the operatingpressure at which maximum oscillations are observed depends slightly on the gas mixture composition.

关键词： Seal stabilities vibration FSI CFD multiphase flows hydrogen

Area and shape distortions in open-source discrete global grid systems

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Big Earth Data 2022年第3期6卷 256-275页

作者： Alexander Kmoch ivan Vasilyev Holger Virro Evelyn Uuemaa Department of Geography Institute of Ecology and Earth SciencesUniversity of TartuTartuEstonia

A Discrete Global Grid System(DGGS)is a type of spatial reference system that tessellates the globe into many individual,evenly spaced,and well-aligned cells to encode location and,thus,can serve as a basis for data cube *** facilitates integration and aggregation of multi-resolution data from various sources to rapidly calculate spatial *** calculated normalized area and compactness for cell geometries from 5 open-source DGGS implementations-Uber H3,Google S2,RiskAware OpenEAGGR,rHEALPix by Landcare Research New Zealand,and DGGRID by Southern Oregon University-to evaluate their suitability for a global-level statistical data *** conclude that the rHEALPix and OpenEAGGR and DGGRID ISEA-based DGGS definitions are most suitable for global statistics because they have the strongest guarantee of equal area preservation-where each cell covers almost exactly the same area on the *** H3 has the smallest shape distortions,but Uber H3 and Google S2 have the largest variations in cell ***,they provide more mature software library *** provides excellent functionality to construct grids with desired geometric properties but as the only implementation does not provide functions for traversal and navigation within a grid after its construction.

关键词： Coordinate reference systems spatial indexing big spatial data analytics data cube DGGS

Iron casting skin management in no-bake mould – Effects of magnesium residual level and mould coating

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China Foundry 2015年第3期12卷 222-230页

作者： Mihai Chisamera Nicoleta ivan Iulian Riposan Stelian Stan POLITEHNICA University of Bucharest

The relative performance of coatings for furan resin sand moulds [P-toluol sulphonic acid(PTSA) as hardener] [FRS-PTSA moulds], was compared by analyzing the surface layer for degenerated graphite in Mg treated iron with 0.020 wt.% to 0.054 wt.% Mgres. It was found that the iron nodularising potential(Mg, Ce, La content) and whether the mould coatings contained S, or were capable of desulphurizing were important factors. These moulds have S in the PTSA binder, which aggravates graphite degeneration in the surface layer, depending strongly on the Mgres with lower Mgres increasing the layer thickness. The application of a mould coating strongly influenced graphite deterioration in the surface layer of castings. It either promoted graphite degeneration to less compact morphologies when using S-bearing coatings, or conversely, limited the surface layer thickness using desulphurization type coatings. Independently of the S-source at the metal – mould interface, the presence of sulphur had an adverse effect on graphite quality at the surface of Mg-treated irons, but its negative effect could also reach the graphite phase within the casting section. If the coatings employed desulphurization materials, such as Mg O, or a mixture(Ca O + Mg O + Talc) or Mgbearing Fe Si, they protected the graphite shape, improving graphite nodularity, at the metal – mould interface, and so decreased the average layer thickness in FRS-PTSA moulds. Fe Si Mg was highly efficient in minimizing the casting skin by improving graphite nodularity. It is presumed that the Mg O or(Mg O + Ca O + Talc) based coatings acted to remove any S released by the mould media. The Mg-Fe Si coatings also reacted with S from the mould but additionally supplemented the Mg nodularising potential prior to solidification. This dual activity is achievable with coatings containing active magnesium derived from fine Mg-Fe Si materials.

关键词： ductile iron compacted graphite iron surface layer graphite degeneration resin bonded sand mould Mg-bearing mould coating S-bearing mould coating

Real-time intersection vehicle turning movement counts from live UAV video stream using multiple object tracking

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Journal of Intelligent and Connected Vehicles 2023年第3期6卷 149-160页

作者： Yuhao Wang ivan Wang-Hei Ho Yuhong Wang Department of Electrical and Electronic Engineering The Hong Kong Polytechnic UniversityHong Kong SARChina Otto Poon Charitable Foundation Smart Cities Research Institute The Hong Kong Polytechnic UniversityHong Kong SARChina Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong SARChina

The intelligent transportation system(ITS)is committed to ensuring safe and effective next-generation traffic throughout a ***,such efficient operation on urban traffic networks needs the support of big traffic data,especially Turning Movement Counts(TMC)at ***,TMC data are more challenging to collect due to labor cost and accuracy *** this paper,we leverage the capabilities of Unmanned Aerial Vehicles(UAV)to collect real-time TMC data in a cost-efficient *** proposed a real-time TMC data collection framework based on a live video *** vehicle tracking capability is boosted by multiple object tracking based on tracking by *** addition,a challenging case study was conducted,and our results demonstrate the feasibility and robustness of the proposed TMC data collection ***,with a GTX 1650 graphics card,about 10 FPS can be achieved in real-time for the TMC data *** overall accuracy is 91.93%,and the best case is over 98%*** the context of miscounting,the major reason is due to ID switching caused by background *** proposed framework is expected to provide real-time data for traffic capacity analysis and advanced traffic simulation such as digital twins.

关键词： turning movement counts unmanned aerial vehicles multi objects tracking real-time

Satellite Image Classification Using a Hybrid Manta Ray Foraging Optimization Neural Network

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Big Data Mining and Analytics 2023年第1期6卷 44-54页

作者： Amit Kumar Rai Nirupama Mandal Krishna Kant Singh ivan Izonin Department of Electronics Engineering Indian Institute of TechnologyDhanbad(ISMDhanbad)Dhanbad 826004India Department of Electronics and Communication Engineering Asansol Engineering CollegeAsansol 713305India Department of CSE ASETAmity UniversityNoida 201301India Department of Artificial Intelligence Lviv Polytechnic National UniversityLviv 79000Ukraine

A semi supervised image classification method for satellite images is proposed in this *** satellite images contain enormous data that can be used in various *** analysis of the data is a tedious task due to the amount of data and the heterogeneity of the ***,in this paper,a Radial Basis Function Neural Network(RBFNN)trained using Manta Ray Foraging Optimization algorithm(MRFO)is *** is a three-layer network comprising of input,output,and hidden layers that can process large *** trained network can discover hidden data patterns in unseen *** learning algorithm and seed selection play a vital role in the performance of the *** seed selection is done using the spectral indices to further improve the performance of the *** manta ray foraging optimization algorithm is inspired by the intelligent behaviour of manta *** emulates three unique foraging behaviours namelys chain,cyclone,and somersault *** satellite images contain enormous amount of data and thus require exploration in large search *** spiral movement of the MRFO algorithm enables it to explore large search spaces *** proposed method is applied on pre and post flooding Landsat 8 Operational Land Imager(OLI)images of New Brunswick *** method was applied to identify and classify the land cover changes in the area induced by *** images are classified using the proposed method and a change map is developed using post classification *** change map shows that a large amount of agricultural area was washed away due to *** measurement of the affected area in square kilometres is also performed for mitigation *** results show that post flooding the area covered by water is increased whereas the vegetated area is *** performance of the proposed method is done with existing state-of-the-art methods.

关键词： Radial Basis Function Neural Network(RBFNN) Manta Ray Foraging Optimization algorithm(MRFO) Landsat 8 classification change detection disaster mitigation planning

PNN-SVM Approach of Ti-Based Powder’s Properties Evaluation for Biomedical Implants Production

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Computers, Materials & Continua 2022年第6期71卷 5933-5947页

作者： ivan Izonin Roman Tkachenko Michal Gregus Zoia Duriagina Nataliya Shakhovska Lviv Polytechnic National University Lviv79013Ukraine Comenius University in Bratislava Bratislava82005Slovak Republic The John Paul II Catholic University of Lublin Lublin20-708Poland

The advent of additive technologies has provided a significant breakthrough in the production of medical *** has reduced costs,increased productivity and accuracy of the implant manufacturing ***,there are problems associated with assessing defects in the microstructure,mechanical and technological properties of alloys,both during their production by powder metallurgy and in the process of 3D *** traditional research methods of alloys properties demand considerable human,material,and time *** the same time,artificial intelligence tools create opportunities for intelligent evaluation of the conformity for the microstructure,phase composition,and properties of titanium powder’s *** provides new possibilities for the efficient production of biocompatible implants for various functional ***,the accuracy of the methods and models used should be as high as *** this paper we designed a hybrid PNN-SVM(Probabilistic Neural Network-Support Vector Machine)high-precision approach for the intelligent evaluation of alloy properties for additive manufacturing of biomedical *** have proposed a new approach for extending the dimensionality of input data space by the outputs of the summation layer of the modified PNN *** classification based on the expanded dataset is performed using *** conducted experimental modeling of the proposed approach using a data set on the properties of titanium alloys Ti-6Al-4V and *** have demonstrated a significant increase in the accuracy of the PNN-SVM scheme compared to the single classifiers that form it and other machine learning methods.

关键词： PNN SVM hybrid systems classification accuracy medical implants additive manufacturing 3D printing titanium alloys