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BER Performance of Finite in Time Optimal FTN Signals for the Viterbi Algorithm

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Journal of Electronic Science and Technology 2020年第1期18卷 42-51页

作者： Sergey B.Makarov ilya I.Lavrenyuk Anna S.Ovsyannikova Sergey V.Zavjalov Higher School of Applied Physics and Space Technologies Peter the Great St.Petersburg Polytechnic UniversitySt.Petersburg 195251

In this article, we consider the faster than Nyquist(FTN) technology in aspects of the application of the Viterbi algorithm(VA). Finite in time optimal FTN signals are used to provide a symbol rate higher than the "Nyquist barrier" without any encoding. These signals are obtained as the solutions of the corresponding optimization problem. Optimal signals are characterized by intersymbol interference(ISI). This fact leads to significant bit error rate(BER) performance degradation for "classical" forms of signals. However, ISI can be controlled by the restriction of the optimization problem. So we can use optimal signals in conditions of increased duration and an increased symbol rate without significant energy losses. The additional symbol rate increase leads to the increase of the reception algorithm complexity. We consider the application of VA for optimal FTN signals reception. The application of VA for receiving optimal FTN signals with increased duration provides close to the potential performance of BER,while the symbol rate is twice above the Nyquist limit.

关键词： Bit error rate(BER)performance faster than Nyquist(FTN) Nyquist limit optimal signals Viterbi algorithm(VA)

The Flow of Liquid Metal in the MHD-Stirrer for Cylindrical Moulds

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Journal of Iron and Steel Research(International) 2012年第S1期19卷 544-547页

作者： ilya Kolesnichenko Ruslan Khalilov Alexander Pavlinov Institute of Continuous Media Mechanics UB RASPermRussia Perm National Research Polytechnic University PermRussia

We study the operation of the MHD stirrer in a cylindrical channel with a liquid metal based on the results of experiments and 3D numerical *** investigations described in this paper are focused on electromagnetic and hydrodynamic *** studied the forces acting on cylinders of different height placed inside the stirrer and calculated the intensity of electromagnetic forces as a function of the value and fiequency of the feeding current. Experimental investigations of the velocity field and its oscillations in a cylindrical crucible filled with a gallium alloy were performed using ultrasonic Doppler velocimeter measurements.

关键词： travelling and rotating magnetic fields continuous casting mixing of melting metal

Findings on intraprocedural non-contrast computed tomographic imaging following hepatic artery embolization are associated with development of contrast-induced nephropathy

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World Journal of Nephrology 2020年第2期9卷 33-42页

作者： Mohamed M Soliman Debkumar Sarkar ilya Glezerman Majid Maybody Interventional Radiology Service Memorial Sloan Kettering Cancer CenterNew YorkNY 10065United States Department of Medicine Memorial Sloan Kettering Cancer CenterNew YorkNY 10065United States

BACKGROUND Contrast-induced nephropathy(CIN)is a reversible form of acute kidney injury that occurs within 48-72 h of exposure to intravascular contrast *** is the third leading cause of hospital-acquired acute kidney injury and accounts for 12%of such *** factors for CIN development can be divided into patientand *** former includes pre-existing chronic renal insufficiency and diabetes *** latter includes high contrast volume and repeated exposure over 72 *** incidence of CIN is relatively low(up to 5%)in patients with intact renal ***,in patients with known chronic renal insufficiency,the incidence can reach up to 27%.AIM To examine the association between renal enhancement pattern on non-contrast enhanced computed tomographic(CT)images obtained immediately following hepatic artery embolization with development of *** Retrospective review of all patients who underwent hepatic artery embolization between 01/2010 and 01/2011(n=162)was *** without intraprocedural CT imaging(n=51),combined embolization/ablation(n=6)and those with chronic kidney disease(n=21)were *** study group comprised of 84 patients with 106 *** was defined as 25%increase above baseline serum creatinine or absolute increase≥0.5 mg/dL within 72 h ***-embolization CT was reviewed for renal enhancement patterns and presence of renal artery *** association between noncontrast CT findings and CIN development was examined by Fisher’s Exact *** CIN occurred in 11/106(10.3%)procedures(Group A,n=10).The renal enhancement pattern in patients who did not experience CIN(Group B,n=74 with 95/106 procedures)was late excretory in 93/95(98%)and early excretory(EE)in 2/95(2%).However,in Group A,there was a significantly higher rate of EE pattern(6/11,55%)compared to late excretory pattern(5/11)(P<0.001).A significantly higher percentage of patients that developed CIN had re

关键词： Hepatic artery embolization Non-contrast computed tomographic Contrastinduced nephropathy Renal enhancement pattern Intra-arterial Renal artery calcification

A Study of the Velocity Field of Liquid Sodium in a Toroidal Channel

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Journal of Iron and Steel Research(International) 2012年第S1期19卷 592-595页

作者： RUSLAN Khalilov ilya Kolesnichenko RODION Stepanov Institute of Continuous Media Mechanics UB RAS Perm 614013Russia

The velocity field of liquid sodium in a toroidal channel is *** measurements are made using the magnetic induction *** proposed technique involves two steps:an external alternating magnetic field of certain frequency is induced in the channel;then the measurements of the resulting magnetic field are used to reconstruct the velocity profile.

关键词： toroidal channel liquid sodium reconstruct velocity profile

Risk factors and urinary biomarkers of non-albuminuric and albuminuric chronic kidney disease in patients with type 2 diabetes

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World Journal of Diabetes 2019年第11期10卷 517-533页

作者： Anton I Korbut Vadim V Klimontov ilya V Vinogradov Vyacheslav V Romanov Laboratory of Endocrinology Research Institute of Clinical and Experimental Lymphology-Branch of the Institute of Cytology and GeneticsSiberian Branch of Russian Academy of Sciences(RICEL-Branch of IC&G SB RAS)Novosibirsk 630060Russia Clinical Laboratory “MBU-Technology”ltd.Novosibirsk 630090Russia

BACKGROUND A number of recent studies indicate a transformation in the natural course of chronic kidney disease(CKD)in type 2 diabetes(T2D)patients:an increasing prevalence of declined renal function without proceeding to the accompanying elevation of *** has been suggested that albuminuric and nonalbuminuric CKD patterns could be different in their phenotypes and pathogenic *** To identify the risk factors and biomarkers of albuminuric and non-albuminuric patterns of CKD in patients with *** Three hundred sixty patients with T2D duration≥10 years were included in this observational cross-sectional *** associations of a panel of demographic and clinical characteristics,complications,comorbidities,and metabolic and hematology parameters with albuminuric and non-albuminuric CKD patterns were *** urinary excretion of nephrin and podocin,two podocytespecific markers,and WAP-four-disulfide core domain protein 2(WFDC-2),a marker of tubulointerstitial fibrosis,was determined by ELISA in comparison with healthy *** Non-albuminuric CKD was associated with age≥65 years(P=0.0001),female sex(P=0.04),diabetes duration≥15 years(P=0.0009),and the use of diuretics(P=0.0005).Male sex(P=0.01),smoking(P=0.01),waist-to-hip ratio>1.0(P=0.01)and hemoglobin A1c(HbA1c)>8.0%(P=0.005)were risk factors for elevated albuminuria not accompanied by a decrease in estimated glomerular filtration rate(eGFR).Duration of diabetes≥15 years and the use of calcium channel blockers were risk factors for albuminuria with decreased eGFR(both P=0.01).In multivariate logistic regression analysis,age,HbA1c,female sex and diuretics were significant predictors for reduced eGFR,while waist-to-hip ratio,HbA1c and male sex were associated with elevated urinary albumin-to-creatinine ratio(UACR).Excretion of nephrin and podocin was increased in patients with albuminuria,regardless of decline in renal function(P<0.001),correlating positively with *** urin

关键词： Diabetes mellitus Chronic kidney disease Albuminuria Glomerular filtration rate Podocytes Risk factors Biomarkers

Cosmological Constant and Energy Density of Random Electromagnetic Field

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Journal of High Energy Physics, Gravitation and Cosmology 2016年第3期2卷 312-319页

作者： ilya A. Obukhov Research & Development Company “System Recourses” Moscow Russia

It is shown that the non-equilibrium electrically neutral and relativistically invariant vacuum-like state with the negative energy density and positive pressure may exist at the non-zero temperature in the system of spinor particles, antiparticles, and random electromagnetic field generated by particle-particle, particle-antiparticle, and antiparticle-antiparticle transitions. At the temperature of the order of 10 -5 K, the energy density of its state corresponds to the dark energy density in absolute magnitude. The cosmological constant for such material medium turns out to be negative.

关键词： Dark Energy Cosmological Constant Stochastic Electromagnetic Field Spinor Particles

Perspectives on protected area and wildfire management in the Black Sea region

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Journal of Forestry Research 2020年第1期31卷 257-268页

作者： George N.Zaimes Petros A.Tsioras Chrysovalantis Kiosses Mustafa Tufekcioglu Sergiy Zibtsev ilya Trombitsky Razvan Uratu Luiza Gevorgyan Department of Forestry and Natural Environment Management Eastern Macedonia and Thrace Institute of Technology(EMaTTech)1st km Drama66100 MikrohoriouDramaGreece Department of Forestry and Natural Environment Aristotle University of ThessalonikiP.O.Box 22754124 Thessalonı´kiGreece 66100 Choristi DramaGreece Artvin Coruh University ArtvinTurkey National University of Life and Environmental Sciences of Ukraine KievUkraine Eco-TIRAS International Association of River Keepers Chis¸ina˘uRepublic of Moldova Prefect’s Institution of Braila County BrailaRomania Zikatar Environmental Centre Ministry of Nature ProtectionYerevanRepublic of Armenia

Protected areas are necessary for the conservation and enhancement of *** are major threats to forests and other natural areas,because they may cause irreversible *** aim of this study was to analyze the perspective of experts(N=284),from six countries of the Black Sea,on the current status and problems of protected areas and *** their points of view could enhance future management on these issues in the *** collection was carried out for 9 months,using a web-based *** were perceived as a serious problem in Turkey,Armenia and Greece but as a substantially less serious problem in Romania,Ukraine and *** Greece,Armenia,and especially Ukraine,the current designated protected areas are considered sufficient to maintain biodiversity,while in Romania,Turkey,and especially Moldova,more areas should be designated as protected.A major need in all countries(except for Turkey)is the increased use of information and communication technologies for both wildfire suppression and protected area *** were divided on whether wildfire suppression and management of protected areas are ***,there is growing awareness of the adverse impacts of climate change in protected areas and the frequency of wildfires in the *** most frequently suggested measures to alleviate these impacts were:changes in forest management and increasing public awareness for wildfire suppression,along with changes in forest management and increased staff training to enhance protected area conservation.

关键词： Climate change Experts Forested areas Web-based questionnaires

在非结构网格上求解非线性航空声学问题的高精度有限体积法(英文)

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Chinese Journal of Aeronautics 2006年第2期19卷 97-104页

作者： ilya ABALAKIN Alain DERVIEUX Tatiana KOZUBSKAYA Institute for Mathematical Modelling RAS . MoscowRussia INRIA Sophia-Antipolis France Institute for Mathematical Modelling RAS . MoscowRussia

The paper presents a finite volume numerical method universally applicable for solving both linear and nonlinear aeroacoustics problems on arbitrary unstructured meshes. It is based on the vertexcentered multi-parameter scheme offering up to the 6th accuracy order achieved on the Cartesian meshes. An adaptive dissipation is added for the numerical treatment of possible discontinuities. The scheme properties are studied on a series of test cases, its efficiency is demonstrated at simulating the noise suppression in resonance-type liners.

关键词： nonlinear aeroacoustics Euler based models finite volume method high accuracy approximation unstructured meshes liners

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Nanoporous magnesium

Nano Research 2018年第12期11卷 6428-6435页

作者： ilya Vladimirovich Okulov Sviatlana V.Lamaka Takeshi Wada Kunio Yubuta Mikhail L.Zheludkevich Jorg Weissmuller Jurgen Markmann Hidemi Kato Institute for Materials Research Tohoku UniversityKatahira 2-1-1Sendai980-8577Japan Institute of Materials Research Materials MechanicsHelmholtz-Zentrum Geesthacht21502GeesthachtGermany MagiC-Magnesium Innovation Centre Helmholtz-Zentrum Geesthacht21502GeesthachtGermany Faculty of Engineering University of Kiel24118KielGermany Institute of Materials Physics and Technology Hamburg University of Technology21073HamburgGermany

In this study, we present freestanding nanoporous magnesium as a novel lightweight material with high potential for structural and functional applications. Thus far, the high reactivity of Mg with oxygen and aqueous media prevented the fabrication of nanoporous Mg. First, in order to synthesize nanoporous Mg, we fabricated a bicontinuous nanocomposite consisting of interpenetrating Mg and non-Mg phases by liquid metal dealloying. The non-Mg phases in the nanocomposite protect Mg against corrosion. Second, we etched the non-Mg phases from the nanocomposite, leaving nanoporous Mg, using HF solution. This process is advantageous because the nanoporous Mg was passivated by a MgF2 layer during the etching. Our approach is very flexible, and we demonstrate that versatile microstructures of the nanoporous Mg—e.g., nanoscale bicontinuous network, hierarchical, or plate-like structures—can be designed for the given needs. More importantly, these nanoporous Mg samples can readily be exposed to air without being harmed by corrosion.

关键词： dealloying nanoporous magnesium