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Triggers and sources of volatile-bearing plumes in the mantle transition zone

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Geoscience Frontiers 2015年第5期6卷 679-685页

作者： Inna Safonova konstantin Litasov Shigenori Maruyama V.S.sobolev Institute of Geology and Mineralogy SB RAS Novosibirsk State University Earth-Life Science Institute Tokyo Institute of Technology

The paper discusses generation of volatile-bearing plumes in the mantle transition zone(MTZ) in terms of mineral-fluid petrology and their related formation of numerous localities of intra-plate bimodal volcanic series in Central and East *** plume generation in the MTZ can be triggered by the tectonic erosion of continental crust at Pacific-type convergent margins and by the presence of water and carbon dioxide in the *** probable sources of volatiles are the hyclrated/carbonated sediments and basalts and serpentinite of oceanic slabs,which can be subducted down to the deep *** erosion of continental crust supplies crustal material enriched in uranium and thorium into the mantle,which can serve source of heat in the *** heating in the MTZ induces melting of subducted slabs and continental crust and mantle upwelling,to produce OIB-type mafic and felsic melts,respectively.

关键词： Asis Pacific-type convergent margin Continental cr

Information in the Structure of Reality:the Scientific Worldview and the Fundamental Question of Philosophy

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学术界 2015年第1期 257-260页

作者： konstantin Kolin Institute of Informatics Problems of the Russian Academy of Sciences

We offer a new understanding of the scientific world and the contents of the basic question of philosophy,which is based on an analysis of the phenomenon of the specific information in the various components of the structure of *** is shown that,in addition to material objects,processes,and events,in the real world are also intangible objects,processes and conditions that are in its information *** the basic question of philosophy is proposed to treat the relationship as a tangible and intangible component of *** succinctly it can be formulated as the ratio of matter and *** allows you to point to some new challenges studying the phenomenon of information in various components of the structure of reality.

关键词：结构信息科学世界观哲学组成部分现实世界信息内容事件

Entropy method of measuring and evaluating periodicity of quasi-periodic trajectories

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Science China(Physics,Mechanics & Astronomy) 2018年第6期61卷 30-49页

作者： Yanshuo Ni konstantin Turitsyn Hexi Baoyin Junfeng Li School of Aerospace Engineering Tsinghua University Department of Mechanical Engineering Massachusetts Institute of Technology

This paper presents a method for measuring the periodicity of quasi-periodic trajectories by applying discrete Fourier transform （DFT） to the trajectories and analyzing the frequency domain within the concept of entropy. Having introduced the concept of entropy, analytical derivation and numerical results indicate that entropies increase as a logarithmic function of time. Periodic trajectories typically have higher entropies, and trajectories with higher entropies mean the periodicities of the motions are stronger. Theoretical differences between two trajectories expressed as summations of trigonometric functions are also derived analytically. Trajectories in the Henon-Heiles system and the circular restricted three-body problem （CRTBP） are analyzed with the indicator entropy and compared with orthogonal fast Lyapunov indicator （OFLI）. The results show that entropy is a better tool for discriminating periodicity in quasiperiodie trajectories than OFLI and can detect periodicity while excluding the spirals that are judged as periodic cases by OFLI. Finally, trajectories in the vicinity of 243 Ida and 6489 Golevka are considered as examples, and the numerical results verify these conclusions. Some trajectories near asteroids look irregular, but their higher entropy values as analyzed by this method serve as evidence of frequency regularity in three directions. Moreover, these results indicate that applying DFT to the trajectories in the vicinity of irregular small bodies and calculating their entropy in the frequency domain provides a useful quantitative analysis method for evaluating orderliness in the periodicity of quasi-periodic trajectories within a given time interval.

关键词： quasi-periodic trajectories entropy quality evaluating

Liver graft preservation methods during cold ischemia phase and normothermic machine perfusion

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World Journal of Gastrointestinal Surgery 2019年第3期11卷 126-142页

作者： konstantin Y Tchilikidi Department of Surgery Altai State Medical University

The growing demand for donor organs requires measures to expand donor *** include extended criteria donors, such as elderly people, steatotic livers,donation after cardiac death, etc. Static cold storage to reduce metabolic requirements developed by Collins in late 1960 s is the mainstay and the golden standard for donated organ protection. Hypothermic machine perfusion provides dynamic organ preservation at 4°C with protracted infusion of metabolic substrates to the graft during the ex vivo period. It has been used instead of static cold storage or after it as short perfusion in transplant center. Normothermic machine perfusion(NMP) delivers oxygen, and nutrition at physiological temperature mimicking regular environment in order to support cellular function. This would minimize effects of ischemia/reperfusion ***, NMP may help to estimate graft functionality before implantation into a recipient. Clinical studies demonstrated at least its non-inferiority or better outcomes vs static cold storage. Regular grafts donated after brain death could be safely preserved with convenient static cold storage. Except for prolonged ischemia time where hypothermic machine perfusion started in transplant center could be estimated to provide possible positive reconditioning effect. Use of hypothermic machine perfusion in regular donation instead of static cold storage or in extended criteria donors requires further investigation. Multicenter randomized clinical trial supposed to be completed in December 2021. Extended criteria donors need additional measures for graft storage and assessment until its implantation. NMP is actively evaluating promising method for this *** studies are necessary for precise estimation and confirmation to issue clinical practice recommendations.

关键词： Liver graft preservation Graft preservation solutions Static cold storage Hypothermic machine perfusion Normothermic machine perfusion Ischemia-reperfusion injury Marginal grafts Donation after cardiac death Extended criteria donors Transplant complications

Numerical simulation of air cavity under a simplified model-scale hull form

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Journal of Ocean Engineering and Science 2020年第1期5卷 68-72页

作者： konstantin I.Matveev School of Mechanical and Materials Engineering Washington State UniversityPullmanWA99164-2920United States

Injecting air under hulls of marine vessels can lead to reduction of their hydrodynamic *** experimental development of air-assisted hulls usually requires a large number of tests,numerical simulations of air-ventilated water flows can potentially accelerate the design *** this study,computational modeling has been carried out for the previously tested simplified hull form with an air cavity formed behind a *** achieve proper agreement with experimental results,it is established that a sufficiently fine numerical mesh needs to be generated at the cavity re-attachment to the hull and the sharpening treatment of the air-water interface must be *** is also shown how the cavity length can be manipulated by changing inclination of the cavity-originating step.

关键词： Drag reduction Air-cavity hull Two-phase flow Computational fluid dynamics Validation and verification

On application of three-dimensional linearized potential-flow model for shallow-water planing

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Journal of Ocean Engineering and Science 2018年第3期3卷 218-222页

作者： konstantin I.Matveev School of Mechanical and Materials Engineering Washington State UniversityPullmanWA 99164-2920USA

Hydrodynamics of planing hulls is affected by proximity to the seabed floor in shallow *** this study,a three-dimensional steady linearized model based on the potential theory is applied to model flat planing surfaces at finite water depth and finite Froude *** results for shallow waters agree with experimental data in the subcritical and supercritical regimes sufficiently far from the critical speed that corresponds to the depth Froude number of *** the critical speed,nonlinear and unsteady effects become important,and a different modeling approach is required.

关键词： Shallow-water effects Planing hulls Potential flow modeling

Mechanisms of cast structure and stressed state formation in Hadfield steel

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China Foundry 2016年第6期13卷 433-442页

作者： Dmitri Gorlenko konstantin Vdovin Nikolay Feoktistov Nosov Magnitogorsk State Technical University Magnitogorsk Russia

The paper describes the investigation of mechanisms of cast structure formation in Hadfield steel depending on the changes in the cooling rate of a casting in the following two temperature ranges： crystallization temperature（1,200-1,390 ℃） and the temperature of excessive phase separation（560-790 ℃）. Changes in the cooling rate of the crystallization temperature range from 1.1 to 25.0 ℃s^-1 result in the reduction of the average size of austenite grains from 266 to 131 μm. At the same time, the magnitude of developing shrinkage stresses changes from ＋195 to 0 MPa. When the cooling rate is higher than 16 ℃^-1, no shrinkage stresses are formed in the casting. Changes in the cooling rate of the casting in the temperature range of the excessive phase separation influence the number of phases, their morphology and chemical composition, the values of phase stresses, and the possibility of martensitic transformation. Changing in the cooling rate from 0.24 to 5.46 ℃^-1 results in the decrease of the amount of the excessive phase from 14.8% to 2.1%, which is composed of eutectic and carbides depending on the cooling rate, their quantitative ratio and morphology change. Such changes in the microstructure are reflected on the changes of value of developing phase stresses. When the cooling rate is 0.24 ℃^-1, it is ＋100 MPa, while the increase of the cooling rate to 1.4 ℃^-1 results in the decrease of tensile stresses to 0 MPa and their qualitative stresses change to compressive ones. Further increase of the cooling rate results in the increase of the value of compressive stresses. When the cooling rate is 5.5 ℃^-1, their value reaches-92 MPa. Martensite forming in the structure of Hadfield steel is possible if the cooling rate of the casting in the range of excessive phase separation is less than 0.25 ℃^-1.

关键词： Hadfield steel crystallization austenite excessive phase stress

DBSC-Based Grayscale Line Image Vectorization

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Journal of Computer Science & Technology 2006年第2期21卷 244-248页

作者： konstantin Melikhov 田丰邱杰陈泉谢福顺 Nanyang Technological University School of Computer Engineering Singapore

Vector graphics plays an important role in computer animation and imaging technologies. However present techniques and tools cannot fully replace traditional pencil and paper. Additionally, vector representation of an image is not always available. There is not yet a good solution for vectorizing a picture drawn on a paper. This work attempts to solve the problem of vectorizing grayscale line drawings. The solution proposed uses Disk B-Spline curves to represent strokes of an image in vector form. The algorithm builds a vector representation from a grayscale raster image, which can be a scanned picture for instance. The proposed method uses a Gaussian sliding window to calculate skeleton and perceptive width of a stroke. As a result of vectorization, the given image is represented by a set of Disk B-Spline curves.

关键词： vectorization skeletonization Disk B-Spline curves

Development of a software package for determination of geodynamic parameters from combined processing of SLR data from LAGEOS and LEO

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Geodesy and Geodynamics 2017年第3期8卷 213-220页

作者： konstantin Ebauer Institute of Astronomy Russian Academy of Sciences

In this study, a method for determination of stations coordinates, Earth rotation parameters and gravity field coefficients in one solution from SLR data from LAGEOS and LEO is presented. A new software package based on the presented method has been developed. All recommendations from IERS Con- ventions 2010 have been included. In addition, some other perturbations and loading effects are taken into account： atmospheric tides, non-tidal atmosphere and ocean variability, albedo and non-tidal at- mospheric pressure loading. Results of different solutions with the use of only LAGEOS data or LAGEOS plus LEO satellites data are presented. Pole coordinates obtained from both solutions show comparable accuracy relative to IERS 08 C04 solution. As for UT1 corrections in terms of Length-of-Day an additional improvement in accuracy is found： 1.0 ms for LAGEOS and 0.2 ms for the combined LAGEOS ＋ LEO solution. Time series of the estimated degree-2 gravity field coefficients show a very good agreement with results of the Center of Space Research （Austin/USA）. As a final remark, some future mandatory steps are outlined.

关键词： SLR LAGEOS LEO Gravity field Earth rotation GGOS