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On a Fixed Point Theorem of Ky Fan

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Acta Mathematica sinica,English series 2002年第2期18卷 363-374页

作者： DE BLAsI Francesco s. GEORGIEV Pando gr. Department of Mathematics.University of Roma Ⅱ'Tor Vergata.Via della Ricerca scientifica.00133 Roma.Italy Department of Mathematics and Informatics SofiaUniversity"St.Kl.Ohridski"5 James Bourchier Blvd.1126 Sofia.Bulgaria and Laboratory for Advanced Brain Signal Processing.Brain Science Institute.The Institute of Physical and Chemical Research(RIKEN)2-1HirosawaWako-shiSaitama.351-0198.Japan

We generalize a theorem of Ky Fan about the nearest distance between a closed convex set D in a Banach space E and its image by a function f:D→E,in several directions:(1)for noncompact sets *** f(D)precompact:(2)for compact D and upper semicontinuous multifunction f:and more generally,(3)for noncompact D and upper semicontinuous multifunction f with f(D)Hausdorff precompact. In particular,we prove a version of the fixed point theorem of Kakutani-Ky Fan for multifunctions. whose values are convex closed bounded,thus not necessarily compact.

关键词： Ky Fan Compact h-compact Upper semicontinuous Multifunction

The mutual interaction between the host spinal cord and grafted undifferentiated stem cells fosters the production of a lesion-induced secretome

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Neural Regeneration Research 2020年第10期15卷 1844-1845页

作者： Krisztián Pajer Tamás Bellák Antal Nógrádi Department of Anatomy Histology and Embryology Faculty of Medicine University of Szeged

Pathophysiology of spinal cord injury:Injury to the spinal cord results in loss of gray and white matter i.e.,it produces a segmental spinal cord lesion and,as a consequence leads to a fatal loss of motor,sensory and autonomic *** cord injuries in humans and other mammals are not followed by the replacement of lost neurons and oligodendrocytes and regrowth of injured axons,instead they lead to permanent,fatal and incurable functional *** primary physical injury is followed by a cascade of tissue-decaying events,called secondary injury,which leads to ischemia,vascular disruption,neuroinflammation,excitotoxicity,demyelination and death of neurons and glial cells(silva et al.,2014;Figure 1A).The direct mechanical disruption of the vasculature results in the increased permeability of the blood-spinal cord *** to the leakiness of blood-spinal cord barrier and production of cytokines by activated microglia,a number of various immune cells(T lymphocytes,neutrophils and monocytes)invade the injury *** macrophages generate a set of inflammatory cytokines such as tumor necrosis factor-α,interleukin(IL)-1α,IL-1β,and IL-6,which may further augment the secondary events(Ahuja et al.,2017).In addition,a number of other disruptive processes contribute to the heterogeneous and time-sensitive pathophysiology of spinal cord injury.

关键词： mutual Figure injuries

Flow-Field Analysis of Anti-Kidney Vortex Film Cooling

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Journal of Thermal science 2012年第1期21卷 66-76页

作者： Lars grf Leonhard Kleiser Institute of Fluid Dynamics

Film cooling is an important measure to enable an increase of the inlet temperature of a gas turbine and, thereby, to improve its overall efficiency. The coolant is ejected through spanwise rows of holes in the blades or endwalls to build up a film shielding the material. The holes often are inclined in the downstream direction and give rise to a kidney vortex. This is a counter-rotating vortex pair, with an upward flow direction between the two vortices, which tends to lift off the surface and to locally feed hot air towards the blade outside the pair. Reversing the rotational sense of the vortices reverses these two drawbacks into advantages. In the considered case, an anti-kidney vortex is generated using two subsequent rows of holes both inclined downstream and yawed spanwise with alternating angles. In a previous study, we performed large-eddy simulations (which focused on the fully turbulent boundary layer) of this anti-kidney vortex film-cooling and compared them to a corresponding physical experiment. The present work analyzes the simulated flow field in detail, beginning in the plenum (inside the blade or endwall) through the holes up to the mixture with the hot boundary layer. To identify the vortical structures found in the mean flow and in the instantaneous flow, we mostly use the λ 2 criterion and the line integral convolution (LIC) technique indicating sectional streamlines. The flow regions (coolant plenum, holes, and boundary layer) are studied subsequently and linked to each other. To track the anti-kidney vortex throughout the boundary layer, we propose two criteria which are based on vorticity and on LIC results. This enables us to associate the jet vortices with the cooling effectiveness at the wall, which is the key feature of film cooling.

关键词： Film cooling anti-kidney vortex vortex identification trajectory tracking large-eddy simulation LEs compound angle double row kidney vortex jet in cross-flow.

Phase-field lattice Boltzmann model for dendrites growing and moving in melt flow

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npj Computational Materials 2019年第1期5卷 140-149页

作者： LászlóRátkai Tamás Pusztai Lászlógránásy Wigner Research Centre for Physics P.O.Box 49H-1525 BudapestHungary Brunel Centre of Advanced solidification Technology Brunel UniversityUxbridgeMiddlesex UB83PHUK

The phase-field and lattice Boltzmann methods have been combined to simulate the growth of solid particles moving in melt *** handle mobile particles,an overlapping multigrid scheme was developed,in which each individual particle has its own moving grid,with local fields attached to *** this approach we were able to simulate simultaneous binary solidification,solute diffusion,melt flow,solid motion,the effect of gravity,and collision of the *** method has been applied for describing two possible modes of columnar to equiaxed transition in the Al–Ti system.

关键词： solidification moving lattice

The Private Tutoring Industry in Denmark: Market Making and Modes of Moral Justification

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ECNU Review of Education 2021年第3期4卷 520-545页

作者： sφren Christensen Thomas grφnbek Frederik Baekdahl Aarhus University IT University of Copenhagen

Purpose:The article focuses on the emergence of a private tutoring industry in Denmark over the last decade. specifically, it explores how private tutoring companies legitimize themselves in a social and cultural context where education has for long predominantly been understood in egalitarian ***/Approach/Methods:The article takes inspiration from Viviana Zelizer’s work on morally controversial markets. It explores the “moral labor” performed by private tutoring companies to redefine the exchange of private tutoring services as a socially wholesome activity. It does so through a close analysis of business information, company websites, and news media articles on private ***:The article argues that, generally, the marketing material of tutoring companies focuses more on social equality and student well-being than on academic success. Thus, the companies predominantly legitimize themselves in terms of long-standing scandinavian ideals of education. Increasingly, these are also the terms in which the companies criticize mainstream ***/Value:The article contributes new knowledge of private tutoring in a scandinavian context where very little research on the issue has so far been conducted. Theoretically, it relates previous research on “legitimation projects” of private tutoring companies to broader sociological theories on market making.

关键词： Denmark market making moral labor private tutoring

Contribution of Fock Term to Properties of Exotic Nuclei

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Chinese Physics Letters 1998年第9期15卷 636-638页

作者： CHEN Bao-qiu MA Zhong-yu s.Krewald F.grümmer China Institute of Atomic Energy Beijing 102413and Center of Nuclear Theoretical PhysicsNational Laboratory of Heavy Ion AccelaratorLanzhou 73000 Institute of Theoretical Physics Chinese Academy of SciencesBeijing 1000803 Institut fur Kernphysik Forschungszentrum Jülich GmbH D-52425 JülichGermany

Density dependent relativistic HartreeFock theory has been extended to describe properties of exotic *** contribution of Fock exchange terms is emphasized in this *** turns out that the influence of Fock terms on prop... 详细信息

关键词： Fock letter turns

Climate Change, Risk and grain Yields in China

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Journal of Integrative Agriculture 2013年第7期12卷 1279-1291页

作者： Rainer Holst Xiaohua Yu Carola grün Courant Research Center 'Poverty Equity and Growth' Georg-August-University of Goettingen World Bank

Adopting Just and Pope （1978, 1979） style yield functions, this paper proposes a method to analyze the impacts of regional climate change on grain production in China. We find that changes in climate will affect grain production in North and south China differently. specifically, it emerges that a 1℃ increase in annual average temperature could reduce national grain output by 1.45% （1.74% reduction in North China and 1.19% reduction in south China）, while an increase in total annual precipitation of around 100 mm could increase national grain output by 1.31% （3.0% increase in North China and 0.59% reduction in south China）.

关键词： grain yield climate change yield risk China

Chemical substances present in discharge water generated by laundry industry:Analytical monitoring

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Water science and Engineering 2023年第4期16卷 324-332页

作者： Dario Lacalamita Chiara Mongioví grégorio Crini Chrono-environnement Laboratory University of Franche-Comté16 Route de GrayBesançon 25000France

To our knowledge,precise data concerning the pollution in terms of qualitative and quantitative fluctuations in discharge water from the laundry sector have seldom been *** study investigated the chemical composition of the discharge water from a laundry *** 160 chemical substances and 15 standard water parameters were *** results showed that the discharge water presented both inorganic and organic polycontamination with a high degree of qualitative and quantitative ***,of all monitored substances,only five metals(Al,Cu,Fe,sr,and Zn),five minerals(P,Ca,K,Na,and s),and alkylphenols were systematically present and *** a daily average water flow of 129 m^(3),the released metal flux was 356 g/***,such as trichloromethane,brominated diphenyl ether(BDE)47,and fluorides,were occasionally found and *** substances,such as chlorophenols,organo-tins,and pesticides were never *** the samples had quantifiable levels in the chemical oxygen demand(COD),biological oxygen demand(BOD),and *** the concentrations of Zn(8.3 g/d),Cu(21.4 g/d),and BOD(57.4 g/d)were close to or above the regulatory values:74.0 g/d for Zn,9.0 g/d for Cu,and 57.0 kg/d for *** data obtained from this study are useful to the choice of additional treatments for the reduction of pollutant fluxes.

关键词： Laundry Discharge water Chemical analysis Water parameter Chemical substance

Mixing Monte-Carlo and Partial Differential Equations for Pricing Options

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Chinese Annals of Mathematics,series B 2013年第2期34卷 255-276页

作者： Tobias LIPP grgoire LOEPER Olivier PIRONNEAU LJLL-UPMC Boite 187Place Jussieu75252 Paris cedex 5France BNP-Paribas 20 Boulevard des Italiens75009 ParisFrance

There is a need for very fast option pricers when the financial objects are modeled by complex systems of stochastic differential *** the authors investigate option pricers based on mixed Monte-Carlo partial differential solvers for stochastic volatility models such as Heston'*** is found that orders of magnitude in speed are gained on full Monte-Carlo algorithms by solving all equations but one by a Monte-Carlo method,and pricing the underlying asset by a partial differential equation with random coefficients,derived by Ito *** strategy is investigated for vanilla options,barrier options and American options with stochastic volatilities and jumps optionally.

关键词： Monte-Carlo Partial differential equations Heston model Financial mathematics. Option pricing