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AN M/M/C RETRIAL QUEUEING SYSTEM WITH bERNOULLI vACATIONS

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Journal of Systems Science and Systems Engineering 2009年第2期18卷 222-242页

作者： b.Krishna KUMAR R.RUKMANI v.THANGARAJ Department of Mathematics College of EngineeringAnna UniversityChennai600 025India Department of Mathematics Pachaiyappa's CollegeChennai600030India Ramanujan Institute for Advanced Study in Mathematics University of MadrasChennai600 005India

In this paper, a steady-state Markovian multi-server retrial queueing system with bernoulli vacation scheduling service is studied. Using matrix-geometric approach, various interesting and important system performance measures are obtained. Further, the probability descriptors like ideal retrial and vain retrial are provided. Finally, extensive numerical illustrations are presented to indicate the quantifying nature of the approach to obtain solutions to this queueing system.

关键词： Retrial queue bernoulli vacation matrix-geometric methods busy period vain retrial ideal retrial

Influence of the safety factor profile on the particle and heat transport in the Globus-M spherical tokamak

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Plasma Science and Technology 2019年第11期21卷 1-6页

作者： A YU TELNOvA G S KURSKIEv E O KISELEv N N bAKHAREv v K GUSEv N A KHROMOv S YU MEDvEDEv v b MIINAEv I v MIROSHNIKOv M I PATROv Yu v PETROv N v SAKHAROv A D SLADKOMEDOvA P b SHCHEGOLEv v v SOLOKHA v A TOKAREv S YU TOLSTYAKOv E A TUKHMENEvA Ioffe Institute Saint-Petersburg 194021Russia Keldysh Institute Russian Academy of SciencesMoscow 125047Russia NRC'Kurchatov Institute’ Moscow 123098Russia

The advanced tokamak scenario is a promising operation scenario for ITER and fusion neutron *** this scenario the minimum value of the safety factor in the center of the plasma exceeds *** the compact spherical tokamak Globus-M,the formation of such conditions is possible with neutral beam injection at the current ramp-up *** to the slower diffusion of current inside the plasma,a zone is formed with reduced heat and particle transport across the magnetic field,which affects the temperature and density profiles of the *** leads to the peaked density profile formation and improvement of the energy confinement *** achieve a high fraction of the bootstrap current,it is necessary to increase the plasma *** the same time,the maximum allowable pressure is limited to the normalized beta limit.

关键词： advanced tokamak mode transport analysis internal transport barriers

Effect of bagasse ash reinforcement on the wear behaviour of Al-Cu-Mg/bagasse ash particulate composites

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Acta Metallurgica Sinica(English Letters) 2010年第2期23卷 81-89页

作者： v.S. Aigbodion S.b. Hassan G.b. Nyior T. Ause Department of Metallurgical and Materials Engineering Ahmadu Bello University

The effect of bagasse ash （bAp） particle reinforcement on the wear behavior of Al-Cu- Mg alloy has been studied. bagasse ash particles were varied from 0 wt pct-10 wt pct with interval of 2 wt pct. Unlubricated pin-on disc tests were conducted to examine the wear behaviour of the aluminium alloy/bagasse ash particulate composites. The tests were conducted at varying loads, from 5 to 20 N and sliding speeds of 1.26 m/s, 2.51 m/s, 3.77 m/s and 5.02 m/s for a constant sliding distance of 5000 m. The results showed that the wear rates of the A1-Cu-Mg/bAp composites are lower than that of the matrix alloy and further decrease with increasing bagasse ash content. Wear rate increases as the sliding speed and applied load increase. The microstructure of the worn surface revealed that a large amount of plastic deformation appeared on the surface of the unreinforced alloy. While bagasse ash reinforced Al-Cu-Mg alloy showed worn out surface that is not smooth, and grooves, scratches and parallel lines were observed. A combination of adhesion and delamination wear was in operation. These results show that improve wear properties is achievable for the aluminium alloy by the addition of bagasse ash particles as reinforcement material.

关键词： Al-Cu-Mg alloy bagasse ash Composites Load Sliding speed and Wear

A SUMMATION FORMULA FOR ESTIMATING THE SURFACE AREAS OF ELLIPSOIDS

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Journal of Computational Mathematics 2004年第3期22卷 403-406页

作者： AnilKumar v.vishnu b. KelappajiCollegeofAgriculturalEngineeringandTechnology KeralaAgriculturalUniversityTavanurKerala679573India

In this paper a summation formula for finding the surface area of general ellipsoids is derived.

关键词： Ellipsoid Prolate spheroid Oblate spheroid Summation formula

On Charged black Hole in Multidimensional Theory with Ricci-Flat Internal Spaces

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Chinese Physics Letters 1991年第9期8卷 439-441页

作者： S.b.Fadeev v.D.Ivashchuk v.N.Melnikov USSR State Committee for Standards 9 Leninski Prospect117049MoscowUSSR

A generalization of the Reissner-Nordstrom solution for the case of n internal Ricci-flat spaces is obtained.

关键词： Ricci generalization Reissner

Ferrofluid nucleus phase transitions in an external uniform magnetic field

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Chinese Physics b 2015年第10期24卷 322-330页

作者： b.M.Tanygin S.I.Shulyma v.F.Kovalenko M.v.Petrychuk Faculty of Radiophysics Taras Shevchenko National University of Kyiv

The phase transition between a massive dense phase and a diluted superparamagnetic phase has been studied by means of a direct molecular dynamics simulation. The equilibrium structures of the ferrofluid aggregate nucleus are obtained for different values of a temperature and an external magnetic field magnitude. An approximate match of experiment and simulation has been shown for the ferrofluid phase diagram coordinates ＂field-temperature＂. The provided phase coexistence curve has an opposite trend comparing to some of known theoretical results. This contradiction has been discussed. For given experimental parameters, it has been concluded that the present results describe more precisely the transition from linear chains to a dense globes phase. The theoretical concepts which provide the opposite binodal curve dependency trend match other experimental conditions： a diluted ferrofluid, a high particle coating rate, a high temperature,and/or a less particles coupling constant value.

关键词： ferrofluid aggregate phase diagram molecular dynamics

Intensification of bituminous coal and lignite oxidation by copper-based activating additives

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International Journal of Coal Science & Technology 2021年第1期8卷 141-153页

作者： K.b.Larionov I.v.Mishakov K.v.Slyusarskiy A.A.vedyagin National Research Tomsk Polytechnic University TomskRussia634050 boreskov Institute of Catalysis Sb RAS NovosibirskRussia630090

The oxidation of lignite and bituminous coal samples modified by 5 wt%(in terms of dry salt)addition of copper salts Cu(NO_(3))_(2),CuSO_(4),and Cu(CH_(3)COO)_(2) was *** samples’reactivity was studied by thermogravimetry within a temperature range of 45–600℃ at a heating rate of 2.5℃/min in an oxidizing *** introduction of activating additives has resulted in a significant decrease in the temperature of intense oxidation onset(ΔT_(i)=20/94℃),in a reduction in the sample residence time in the volatile matter release region(Δt_(e)=2/22 min)and the total duration of the coal combustible mass oxidation(Δt_(f)=8/14 min).The Friedman method was used to calculate the activation energy values for the oxidation process of the modified *** maximum change in activation energy values was observed for the bituminous coal *** possible mechanism behind the action of the copper-salt additives,which activate the oxidation of lignite and bituminous coal,is *** to the data of mass spectrometric analysis,the concentration of NOx in the reaction products decreases as the temperature of the activated oxidation process is shifted towards the low-temperature region.

关键词： Coal Activated oxidation Copper nitrate Copper sulfate Copper acetate Thermo-gravimetric and mass spectrometry analysis

Energy of Grain boundaries of Different Type in fcc Solid Solutions,Ordered Alloys and Intermetallics with L1_2 Superstructure

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Journal of Materials Science & Technology 2003年第6期19卷 593-596页

作者： O.b.Perevalova E.v.Konovalova N.A.Koneva E.v.Kozlov Institute of Strength Physics and Materials Science Russian Academy of Science Siberian Branch Russia TomskState University of Architecture and Building Russia TomskState University of Architecture and Building Russia TomskState University of Architecture and Building Russia Tomsk

The study of the triple junctions of the grain boundaries in some fee solid solutions, ordered alloys and intermetallics with L12 has been carried out using the optical metallography and TEM methods. Two-types of the triple junctions were found in the alloys investigated (1), consisting of the boundaries of the random (RT), and (2), consisting of the RT boundary and the special boundaries (ST). The relative values of the RT and ST boundary energy were determined on the basis of the measurements of the angles between the grain boundary planes. It has been shown that the energy of ST boundaries increases with the increase of the stacking fault (SF) energy. The energy of the RT boundaries does not depend on the SF energy.

关键词： Alloys Grain boundary energy Stacking fault Anti-phase-boundary

Genes associated with testicular germ cell tumors and testicular dysgenesis in patients with testicular microlithiasis

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Asian Journal of Andrology 2018年第6期20卷 593-599页

作者： Ilya S Dantsev Evgeniy v Ivkin Aleksey A Tryakin Dmitriy N Godlevski Oleg Yu Latyshev victoriya v Rudenko Dmitry S Mikhaylenko vyacheslav b Chernykh Elena A volodko Aleksey b Okulov Oleg b Loran Marina v Nemtsova Russian Medical Academy ef Postgraduate Education Moscow 123995Russia N.N.blokhin Russian Cancer Research Center Moscow 115478Russia Research Centre of Medical Genetics Moscow 115478Russia M.Sechenov First Moscow State Medical University Moscow 119991Russia N.I.Pirogov Russian National Research Medical University Moscow 117997Russia.

Testicular microlithiasis （TM） is one of the symptoms of testicular dysgenesis syndrome （TDS）. TM is particularly interesting as an informative marker of testicular germ cell tumors （TGCTs）. KIT ligand gene （KITLG）, bCL2 antagonist/killer 1 （bAK1）, and sprouty RTK signaling antagonist 4 （SPRY4） genes are associated with a high risk of TGCTs, whereas bone morphogenetic protein 7 gene （bMP7）, transforming growth factor beta receptor 3 gene （TGFbR3）, and homeobox D cluster genes （HOXD） are related to TDS. Using polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） analysis, we investigated allele and genotype frequencies for KITLG （rs995030, rs1508595）, SPRY4 （rs4624820, rs6897876）, bAK1 （rs210138）, bMP7 （rs388286）, TGFbR3 （rs12082710）, and HOXD （rs17198432） in 142 TGCT patients, 137 TM patients, and 153 fertile men （control group）. We found significant differences in the KITLG GG_rs995030 genotype in TM （P= 0.01） and TGCT patients （P = 0.0005） compared with the control. We also revealed strong associations between KITLGrs1508595 and TM （G allele, P = 0.003; GG genotype, P= 0.01） and between KITLG_rs1508595 and TGCTs （G allele, P-- 0.0001; GG genotype, P = 0.0007）. Moreover, there was a significant difference in bMP7_rs388286 between the TGCT group and the control （T allele, P = 0.00004; TT genotype, P = 0.00006） and between the TM group and the control （T allele, P= 0.04）. HOXDalso demonstrated a strong association with TGCTs （rs17198432 A allele, P = 0.0001; AA genotype, P = 0.001）. Furthermore, significant differences were found between the TGCT group and the control in the bAK1_rs210138 G allele （P= 0.03） and the GG genotype （P= 0.01）. KITLG and bMP7genes, associated with the development of TGCTs, may also be related to TM. In summary, the KITLG GG_rs995030, GG_rs1508595, bMP7 TT_rs388286, HOXD AA_rs17198432, and bAK1 GG_rs210138 genotypes were associated with a high risk of TGCT development.

关键词： associations genotype high risk testicular dysgenesis syndrome testicular microlithiasis