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Magnetic Orderings and Néel Temperature of TbNi2B2C

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Chinese Physics Letters 2009年第10期26卷 177-180页

作者：刘照森 Divis Martin Sechovsky vladimir Faculty of Mathematics and Physics Nanjing University of Information Science and Technology Nanjing 210044 Department of Condensed Matter Physics Faculty of Mathematics and Physics Charles University Ke Karlovu 5 121 16 Prague 2 Czech Republic

We employ a two-ion model to calculate the spontaneous magnetization and susceptibility of TbNi2B2C with the mean-field theory, and derive an analytic formula for the Néel temperature of the material with the perturbation theory. In both the cases, only the four lowest crystal-electric-field （CEF） states are taken into account as base functions. Our theoretical results are consistent with the experimental data, manifesting the strong effects of the low lying CEF states on the magnetic behaviors of the material and the suitability of the theoretical approach proposed here.

关键词： Condensed matter: electrical magnetic and optical

Eleven species of noctuid moths new to China of the boreal faunal complex(Lepidoptera:Noctuidae)

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Journal of Forestry Research 2020年第4期31卷 1405-1415页

作者： Huilin Han vladimir S.Kononenko School of Forestry Northeast Forestry UniversityHarbin 150014HeilongjiangPeople’s Republic of China Laboratory of Entomology Federal Scientific Center of the East Asia Terrestrial BiodiversityFar Eastern BranchRussian Academy of SciencesVladivostok-22Russia 690022

Eleven species of the Noctuidae[Polia hepatica(Clerck,1759),***(Draudt,1934),***(Draudt,1934),Lasionycta skraelingia(Herrich-Schaffer,1852),*** ***-Haas,1912;Xestia kolymae(Herz,1903),***(Eversmann,1851),***(Staudinger,1897),***(Erschoff,1870),***(Herrich-Schaffer,1851),and ***(Staudinger,1871)]of the boreal faunal complex are reported for the first time from *** of adults and the genitalia of both sexes are *** on these newly recorded species,original descriptions,type-locality,synonyms,references,host plants and bionomics are provided.

关键词： Lepidoptera Noctuidae New records Boreal complex Northeast China

Magnetic Properties of a Rare-Earth Antiferromagnetic Nanoparticle Investigated with a Quantum Simulation Model

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Chinese Physics Letters 2011年第6期28卷 251-254页

作者： LIU Zhao-Sen Sechovský vladimir Diviš Martin Faculty of Mathematics and Physics Nanjing University of Information Science and TechnologyNanjing 210044 Department of Condensed Matter Physics Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 512116 Prague 2Czech Republic

A Usov-type quantum model based on a mean-field approximation is utilized to simulate the magnetic structure of an assumed rare-earth nanoparticle consisting of an antiferromagnetic core and a paramagnetic outer *** study the magnetic properties in the presence and absence of an external magnetic *** simulation results show that the magnetic moments in the core region orientate antiferromagnetically in zero external magnetic field;an applied magnetic field rotates all of the magnetic moments in the paramagnetic shell completely to the field direction,and turns those in the core(which tries to maintain its original antiferromagnetic structure)towards the orientation in some degree;and the paramagnetic shell does not have a strong influence on the magnetic configuration of the core.

关键词： field particle turns

Applicability of high-temperature cooling systems in different European countries from the view of the condensation risk

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Building Simulation 2021年第5期14卷 1453-1466页

作者： vladimir Zmrhal Martin Bartak Czech Technical University in Prague Faculty of Mechanical EngineeringDepartment of Environmental Engineering Technicka 416000 Prague 6Czech Republic

Due to the different approaches in determining the ventilation airflow rate per person for workspaces,where high-temperature air conditioning systems are used for air conditioning,problems with the condensation of water vapour on the cold surfaces of the system can *** article analyses the risk of condensation in various European cities using the available climatic *** with cooling ceilings and cooling beams with a ventilation device operating in parallel are taken into *** ventilation airflow rates per person were *** the example of a room equipped with high-temperature cooling,an energy simulation calculation is performed,which includes a ventilation and air-conditioning system with the possibility of capacity *** is clear from the results that the condensation of water vapour can be prevented by technical measures at the cost of reducing the cooling capacity,which can affect the achievement of the thermal comfort of those *** the end,suitable solutions are discussed,which should already be adopted at the time the device is designed so that the risk of condensation is not a major obstacle in the operation of these energy-efficient *** irreplaceable role in the operation of high-temperature cooling systems is played by a measurement and control system with a suitable algorithm to prevent condensation.

关键词： ventilation air-conditioning cooled ceilings chilled beams low energy cooling risk of condensation

Method of Relaxation Rates Measurement in Proton-Containing Materials

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Journal of Electronic Science and Technology 2020年第1期18卷 10-18页

作者： Sergey Ermak vladimir Semenov Roman Lozov Institute of Physics Nanotechnology and TelecommunicationsPeter the Great St.Petersburg Polytechnic UniversitySt.Petersburg 195251

A method of the relaxation time measurement in a flowing sample, based on the comparison of the amplitudes of nuclear magnetic resonance(NMR) signals observed from the reference and tested flowing samples was represented. The inductive and optical methods of NMR signal detection in the flowing sample were *** levels of NMR signal(10000 Hz-1/2) and the Hanle magnetometers signal-to-noise ratio(3500 Hz-1/2) were calculated and the possibility of the NMR signal detection with the small-size Hanle magnetometer was demonstrated. Additionally, the absence of a magnet-analyzer and the ability to measure both longitudinal and transverse relaxation time with high accuracy was demonstrated.

关键词： Hanle effect magnetic field nuclear magnetic resonance(NMR) quantum magnetometer relaxation time

Negative Magnetoresistivity of ErBi and Its Crystal-Field Levels

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Chinese Physics Letters 2009年第1期26卷 268-271页

A theoretical approach is generalized and employed in this work to evaluate the magnetoresistivity of ErBi in external magnetic fields. The calculated results and theoretical analyses show that when an external magnetic field is applied in the z-direction, the magnetoresistivity can be reduced considerably due to the degeneracy lifting of the crystal-field levels. However, when the magnetic field is exerted along the x-axis, the magnetoresistivity will be increased because of the formations of new magnetic states of the Er ion and its transitions within and between these new states.

关键词： field emission molybdenum dioxide enhancement factor

Evaluation of Energy Saving Operational Modes for Industrial Fracture Connected Processes on the Basis of Incubation Time Fracture Criterion

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Transactions of Tianjin University 2008年第B10期14卷 476-482页

作者： Bratov vladimir Petrov Yuri InstituteofProblemsofMechanicalEngineering 199178St.-PetersburgRussia St.-PetersburgStateUniversity 198504St.-PetersburgRussia

A problem for a central crack in a plate subjected to plane strain conditions is investigated. Mode I crack loading is created by a dynamic pressure pulse applied at a large distance from the crack. It was found that for a certain combination of amplitude and duration of the pulse applied, the energy transmitted to the sample has a strongly marked minimum, meaning that with the pulse amplitude or duration moving away from the optimal values, minimum energy required for initiation of crack growth increases rapidly. The results obtained indicate a possibility to optimise energy consumption of different industrial processes connected with fracture. Much could be gained in, for example, drilling or rock pounding where energy input accounts for the largest part of the process cost. Presumably further investigation of the effect observed can make it possible to predict optimal energy saving parameters, i.e. frequency and amplitude of impacts, for industrial devices, e.g. bores, grinding machines, and hence significantly reduce the process cost. The pre- diction can be given based on the parameters of the media fractured （material parameters, prevalent crack length and orientation, etc.）.

关键词： fracture energy saving incubation time fracture criterion

Computation of Fisher–Gale Equilibrium by Auction

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Journal of the Operations Research Society of China 2018年第3期6卷 473-483页

作者： Yurii Nesterov vladimir Shikhman Center for Operations Research and Econometrics Catholic University of Louvain1348 Louvain-la-NeuveBelgium National Research University Higher School of Economics MoscowRussia Department of Mathematics Technische Universität Chemnitz09126 ChemnitzGermany

We study the Fisher model of a competitive market from the algorithmic *** that,the related convex optimization problem due to Gale and Eisenberg(Ann Math Stat 30(1):165–168,1959)is *** latter problem is known to yield a Fisher equilibrium under some structural assumptions on consumers’utilities,e.g.,homogeneity of degree 1,*** goal is to examine applicability of the convex optimization framework by departing from these traditional *** just assume the concavity of consumers’utility *** this case,we suggest a novel concept of Fisher–Gale equilibrium by using consumers’utility *** prices of utility transfer the utility of consumption bundle to a common numé*** develop a subgradient-type algorithm from Convex Analysis to compute a Fisher–Gale equilibrium via Gale’s *** order to decentralize prices,we additionally implement the auction design,i.e.,consumers settle and update their individual prices and producers sell at the highest offer *** price adjustment is based on a tatonnement procedure,i.e.,the prices change proportionally to consumers’individual excess *** averages of consumption are shown to clear the market of *** algorithm is justified by a global rate of *** the worst case,the number of price updates needed to achieve anε-tolerance is proportional to 1/ε^(2).

关键词： Fisher equilibrium Computation of equilibrium Price adjustment Convex optimization Subgradient methods Decentralization of prices Auction

Task-resource Scheduling Problem

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International Journal of Automation and computing 2012年第4期9卷 429-441页

作者： Anna Gorbenko vladimir Popov Department of Intelligent Systems and Robotics Ural State University

Cloud computing is a new and rapidly emerging computing paradigm where applications, data and IT services are provided over the Internet. The task-resource management is the key role in cloud computing systems. Task-resource scheduling problems are premier which relate to the efficiency of the whole cloud computing facilities. Task-resource scheduling problem is NP-complete. In this paper, we consider an approach to solve this problem optimally. This approach is based on constructing a logical model for the problem. Using this model, we can apply algorithms for the satisfiability problem (SAT) to solve the task-resource scheduling problem. Also, this model allows us to create a testbed for particle swarm optimization algorithms for scheduling workflows.

关键词： Clouds complexity theory scheduling satisfiability problem genetic algorithms