Chen Mingtao
2011-01-01
Full Text Available Abstract This article is concerned with global strong solutions of the micro-polar, compressible flow with density-dependent viscosity coefficients in one-dimensional bounded intervals. The important point in this article is that the initial density may vanish in an open subset.
A coupled chemotaxis-fluid model: Global existence
Liu, Jian-Guo
2011-09-01
We consider a model arising from biology, consisting of chemotaxis equations coupled to viscous incompressible fluid equations through transport and external forcing. Global existence of solutions to the Cauchy problem is investigated under certain conditions. Precisely, for the chemotaxis-Navier- Stokes system in two space dimensions, we obtain global existence for large data. In three space dimensions, we prove global existence of weak solutions for the chemotaxis-Stokes system with nonlinear diffusion for the cell density.© 2011 Elsevier Masson SAS. All rights reserved.
Jian Liu
2013-09-01
Full Text Available In this article, we consider the free boundary value problem for one-dimensional compressible bipolar Navier-Stokes-Possion (BNSP equations with density-dependent viscosities. For general initial data with finite energy and the density connecting with vacuum continuously, we prove the global existence of the weak solution. This extends the previous results for compressible NS [27] to NSP.
Global existence for a degenerate haptotaxis model of cancer invasion
Zhigun, Anna; Surulescu, Christina; Uatay, Aydar
2016-12-01
We propose and study a strongly coupled PDE-ODE system with tissue-dependent degenerate diffusion and haptotaxis that can serve as a model prototype for cancer cell invasion through the extracellular matrix. We prove the global existence of weak solutions and illustrate the model behavior by numerical simulations for a two-dimensional setting.
Global coherence of dust density waves
Killer, Carsten; Melzer, André [Institut für Physik, Ernst-Moritz-Arndt-Universität Greifswald, 17489 Greifswald (Germany)
2014-06-15
The coherence of self-excited three-dimensional dust density waves has been experimentally investigated by comparing global and local wave properties. For that purpose, three-dimensional dust clouds have been confined in a radio frequency plasma with thermophoretic levitation. Global wave properties have been measured from the line-of-sight integrated dust density obtained from homogenous light extinction measurements. Local wave properties have been obtained from thin, two-dimensional illuminated laser slices of the cloud. By correlating the simultaneous global and local wave properties, the spatial coherence of the waves has been determined. We find that linear waves with small amplitudes tend to be fragmented, featuring an incoherent wave field. Strongly non-linear waves with large amplitudes, however, feature a strong spatial coherence throughout the dust cloud, indicating a high level of synchronization.
Zinkina, Julia; Korotayev, Andrey; Andreev, Aleksey I.
2013-01-01
Purpose: The purpose of this paper is to encourage discussions regarding the existing approaches to globalization measurement (taking mainly the form of indices and rankings) and their shortcomings in terms of applicability to developing Global Studies curricula. Another aim is to propose an outline for the globalization measurement methodology…
Zinkina, Julia; Korotayev, Andrey; Andreev, Aleksey I.
2013-01-01
Purpose: The purpose of this paper is to encourage discussions regarding the existing approaches to globalization measurement (taking mainly the form of indices and rankings) and their shortcomings in terms of applicability to developing Global Studies curricula. Another aim is to propose an outline for the globalization measurement methodology…
Theorems on Existence and Global Dynamics for the Einstein Equations
Rendall Alan D.
2005-10-01
Full Text Available This article is a guide to theorems on existence and global dynamics of solutions of the Einstein equations. It draws attention to open questions in the field. The local-in-time Cauchy problem, which is relatively well understood, is surveyed. Global results for solutions with various types of symmetry are discussed. A selection of results from Newtonian theory and special relativity that offer useful comparisons is presented. Treatments of global results in the case of small data and results on constructing spacetimes with prescribed singularity structure or late-time asymptotics are given. A conjectural picture of the asymptotic behaviour of general cosmological solutions of the Einstein equations is built up. Some miscellaneous topics connected with the main theme are collected in a separate section.
Theorems on Existence and Global Dynamics for the Einstein Equations
Rendall Alan
2002-01-01
Full Text Available This article is a guide to theorems on existence and global dynamics of solutions ofthe Einstein equations. It draws attention to open questions in the field. The local-in-time Cauchy problem, which is relatively well understood, is surveyed. Global results for solutions with various types of symmetry are discussed. A selection of results from Newtonian theory and special relativity that offer useful comparisons is presented. Treatments of global results in the case of small data and results on constructing spacetimes with prescribed singularity structure are given. A conjectural picture of the asymptotic behaviour of general cosmological solutions of the Einstein equations is built up. Some miscellaneous topics connected with the main theme are collected in a separate section.
Global Existence of Solutions for Stochastic Impulsive Differential Equations
Li Juan SHEN; Ji Tao SUN
2011-01-01
In this paper we obtain some results on the global existence of solution to It(o) stochastic impulsive differential equations in M([0, ∞),Rn) which denotes the family of Rn-valued stochastic processes x satisfying supt∈[0,∞) E|x(t)|2 ＜∞ under non-Lipschitz coefficients. The Schaefer fixed point theorem is employed to achieve the desired result. An example is provided to illustrate the obtained results.
Small data global existence for a fluid-structure model
Ignatova, Mihaela; Kukavica, Igor; Lasiecka, Irena; Tuffaha, Amjad
2017-02-01
We address the system of partial differential equations modeling motion of an elastic body inside an incompressible fluid. The fluid is modeled by the incompressible Navier-Stokes equations while the structure is represented by the damped wave equation with interior damping. The additional boundary stabilization γ, considered in our previous paper, is no longer necessary. We prove the global existence and exponential decay of solutions for small initial data in a suitable Sobolev space.
Anisotropic Density Estimation in Global Illumination
Schjøth, Lars
2009-01-01
Density estimation employed in multi-pass global illumination algorithms gives cause to a trade-off problem between bias and noise. The problem is seen most evident as blurring of strong illumination features. This thesis addresses the problem, presenting four methods that reduce both noise...... and bias in estimates. Good results are obtained by the use of anisotropic filtering. Two methods handles the most common cases; filtering illumination reflected from object surfaces. One methods extends filtering to the temporal domain and one performs filtering on illumination from participating media...
Global Existence of Solutions for a Nonstrictly Hyperbolic System
De-yin Zheng
2014-01-01
Full Text Available We obtain the global existence of weak solutions for the Cauchy problem of the nonhomogeneous, resonant system. First, by using the technique given in Tsuge (2006, we obtain the uniformly bounded L∞ estimates z(ρδ,ε,uδ,ε≤B(x and w(ρδ,ε,uδ,ε≤β when a(x is increasing (similarly, w(ρδ,ε, uδ,ε≤B(x and z(ρδ,ε,uδ,ε≤β when a(x is decreasing for the ε-viscosity and δ-flux approximation solutions of nonhomogeneous, resonant system without the restriction z0(x≤0 or w0(x≤0 as given in Klingenberg and Lu (1997, where z and w are Riemann invariants of nonhomogeneous, resonant system; B(x>0 is a uniformly bounded function of x depending only on the function a(x given in nonhomogeneous, resonant system, and β is the bound of B(x. Second, we use the compensated compactness theory, Murat (1978 and Tartar (1979, to prove the convergence of the approximation solutions.
Existence of Global Weak Solutions to a Hybrid Vlasov-MHD Model for Magnetized Plasmas
Cheng, Bin; Tronci, Cesare
2016-01-01
We prove the global-in-time existence of large-data finite-energy weak solutions to an incompressible hybrid Vlasov-magnetohydrodynamic model in three space dimensions. The model couples three essential ingredients of magnetized plasmas: a transport equation for the probability density function, which models energetic rarefied particles of one species; the incompressible Navier--Stokes system for the bulk fluid; and a parabolic evolution equation, involving magnetic diffusivity, for the magnetic field. The physical derivation of our model is given. It is also shown that the weak solution, whose existence is established, has nonincreasing total energy, and that it satisfies a number of physically relevant properties, including conservation of the total momentum, conservation of the total mass, and nonnegativity of the probability density function for the energetic particles. The proof is based on a one-level approximation scheme, which is carefully devised to avoid increase of the total energy for the sequence...
Sun Fuqin; Wang Mingxin
2004-01-01
In this paper, we study the non-negative solutions to a degenerate parabolic system with nonlinear boundary conditions in the multi-dimensional case.By the upper and lower solutions method, we give the conditions on the existence and non-existence of global solutions.
THE EXISTENCE AND THE NON-EXISTENCE OF GLOBAL SOLUTIONS OF A FREE BOUNDARY PROBLEM
Yin Rong; Yu Wanghui
2004-01-01
We study a free boundary problem of parabolic equations with a pos-itive parameter τ included in the coefficient of the derivative with respect to the timevariable t. This problem arises from some reaction-diffusion system. We prove that, ifτ is large enough, the solution exists for 0 ＜ t ＜ +∞; while, if τ is small enough, thesolution exists only in finite time.
Wen, Zijuan; Fan, Meng; Asiri, Asim M; Alzahrani, Ebraheem O; El-Dessoky, Mohamed M; Kuang, Yang
2017-04-01
This paper studies the global existence and uniqueness of classical solutions for a generalized quasilinear parabolic equation with appropriate initial and mixed boundary conditions. Under some practicable regularity criteria on diffusion item and nonlinearity, we establish the local existence and uniqueness of classical solutions based on a contraction mapping. This local solution can be continued for all positive time by employing the methods of energy estimates, Lp-theory, and Schauder estimate of linear parabolic equations. A straightforward application of global existence result of classical solutions to a density-dependent diffusion model of in vitro glioblastoma growth is also presented.
Global existence for a singular Gierer-Meinhardt system
Chen, Shaohua; Salmaniw, Yurij; Xu, Runzhang
2017-02-01
This paper is concerned with existence results for a singular Gierer-Meinhardt system subject to zero Dirichlet boundary conditions, which originally arose in studies of pattern-formation in biology. The mathematical difficulties are that the system becomes singular near the boundary and it lacks a variational structure. We use a functional method to obtain both upper and lower bounds for the perturbed system and then use Sobolev embedding theorem to prove the existence of a pair of positive solutions under suitable conditions. This method is first used in a singular parabolic system and is completely different than the traditional methods of sub and super solutions.
Spatially-explicit models of global tree density
Glick, Henry B.; Bettigole, Charlie; Maynard, Daniel S.; Covey, Kristofer R.; Smith, Jeffrey R.; Crowther, Thomas W.
2016-08-01
Remote sensing and geographic analysis of woody vegetation provide means of evaluating the distribution of natural resources, patterns of biodiversity and ecosystem structure, and socio-economic drivers of resource utilization. While these methods bring geographic datasets with global coverage into our day-to-day analytic spheres, many of the studies that rely on these strategies do not capitalize on the extensive collection of existing field data. We present the methods and maps associated with the first spatially-explicit models of global tree density, which relied on over 420,000 forest inventory field plots from around the world. This research is the result of a collaborative effort engaging over 20 scientists and institutions, and capitalizes on an array of analytical strategies. Our spatial data products offer precise estimates of the number of trees at global and biome scales, but should not be used for local-level estimation. At larger scales, these datasets can contribute valuable insight into resource management, ecological modelling efforts, and the quantification of ecosystem services.
Said-Houari, Belkacem
2012-09-01
The goal of this work is to study a model of the viscoelastic wave equation with nonlinear boundary/interior sources and a nonlinear interior damping. First, applying the Faedo-Galerkin approximations combined with the compactness method to obtain existence of regular global solutions to an auxiliary problem with globally Lipschitz source terms and with initial data in the potential well. It is important to emphasize that it is not possible to consider density arguments to pass from regular to weak solutions if one considers regular solutions of our problem where the source terms are locally Lipschitz functions. To overcome this difficulty, we use an approximation method involving truncated sources and adapting the ideas in [13] to show that the existence of weak solutions can still be obtained for our problem. Second, we show that under some restrictions on the initial data and if the interior source dominates the interior damping term, then the solution ceases to exist and blows up in finite time provided that the initial data are large enough.
无
2008-01-01
The authors prove the local existence and uniqueness of weak solution of a hyperbolic-parabolic system and establish the global existence of the weak solution for this system for the spatial dimension n = 1.
Global existence for an L^2 critical Nonlinear Dirac equation in one dimension
Candy, Timothy
2011-01-01
We prove global existence from $L^2$ initial data for a nonlinear Dirac equation known as the Thirring model. Local existence in $H^s$ for $s>0$, and global existence for $s>1/2$, has recently been proven by Selberg and Tesfahun by using $X^{s, b}$ spaces together with a type of null form estimate. In contrast, motivated by the recent work of Machihara, Nakanishi, and Tsugawa, we first prove local existence in $L^2$ by using null coordinates, where the time of existence depends on the profile of the initial data. To extend this to a global existence result we need to rule out concentration of $L^2$ norm, or charge, at a point. This is done by decomposing the solution into an approximately linear component and a component with improved integrability. We then prove global existence for all $s>0$.
SHARP CRITERIONS OF GLOBAL EXISTENCE AND COLLAPSE FOR COUPLED NONLINEAR SCHR(O)DINGER EQUATIONS
Gan Zaihui; Zhang Jian
2004-01-01
In this paper, a series of sharp criterions of global existence and collapse for coupled nonlinear Schrodinger equations are derived out in terms of the characteristics of the ground state and the local theories. And the conclusion that how small the initial data are, the global solutions exist is proved.
Global Existence of a Shock for the Supersonic Flow Past a Curved Wedge
Hui Cheng YIN
2006-01-01
This note is devoted to the study of the global existence of a shock wave for the supersonic flow past a curved wedge. When the curved wedge is a small perturbation of a straight wedge and the angle of the wedge is less than some critical value, we show that a shock attached at the wedge will exist globally.
ZHONG CHENGKUI; SUN CHUNYOU; NIU MINGFEI
2005-01-01
By means of a nonstandard estimation about the energy functional, the authors prove the existence of a global attractor for an abstract nonlinear evolution equation. As an application, the existence of a global attractor for some nonlinear reaction-diffusion equations with some distribution derivatives in inhomogeneous terms is obtained.
Yi DU; Zheng An YAO
2011-01-01
In this paper, we consider the Cauchy problem for systems of quasi-linear wave equations with multiple propagation speeds in spatial dimensions n ≥ 4. The problem when the nonlinearities depend on both the unknown function and their derivatives is studied. Based on some Klainerman- Sideris type weighted estimates and space-time L estimates, the results that the almost global existence for space dimensions n = 4 and global existence for n ≥ 5 of small amplitude solutions are presented.
Haspot, Boris
2012-01-01
We show existence of global strong solutions with large initial data on the irrotational part for the shallow-water system in dimension $N\\geq 2$. We introduce a new notion of \\textit{quasi-solutions} when the initial velocity is assumed to be irrotational, these last one exhibit regularizing effects both on the velocity and in a very surprising way also on the density (indeed the density is a priori governed by an hyperbolic equation). We would like to point out that this smoothing effect is purely non linear and is absolutely crucial in order to deal with the pressure term as it provides new damping effects in high frequencies. In particular our result gives a first kind of answer to the problem of the existence of global weak solution for the shallow-water system. We conclude by giving new point wise decay estimates on the solution which improves the previous works \\cite{HZ1,HZ2}.
Global Existence and Uniqueness of Solutions to Evolution p-Laplacian Systems with Nonlinear Sources
WEI Yingjie; GAO Wenjie
2013-01-01
This paper presents the global existence and uniqueness of the initial and boundary value problem to a system of evolution p-Laplacian equations coupled with general nonlinear terms.The authors use skills of inequality estimation and the method of regularization to construct a sequence of approximation solutions,hence obtain the global existence of solutions to a regularized system.Then the global existence of solutions to the system of evolution p-Laplacian equations is obtained with the application of a standard limiting process.The uniqueness of the solution is proven when the nonlinear terms are local Lipschitz continuous.
EXISTENCE AND GLOBAL ATTRACTIVITY OF ALMOST PERIODIC SOLUTION TO A DELAYED DIFFERENTIAL EQUATION
无
2011-01-01
A new fixed point theorem is presented and sufficient conditions are obtained for the existence, uniqueness and global attractivity of a positive almost periodic solution to a delayed differential equation with almost periodic factors.
Global existence and asymptotic behavior for a nonlinear degenerate SIS model
Tarik Ali Ziane
2013-01-01
Full Text Available In this paper we investigate the global existence and asymptotic behavior of a reaction diffusion system with degenerate diffusion arising in the modeling and the spatial spread of an epidemic disease.
Global Existence of Classical Solutions for Some Oldroyd-B Model via the Incompressible Limit
Zhen LEI
2006-01-01
In this paper, we prove local and global existence of classical solutions for a system of equations concerning an incompressible viscoelastic fluid of Oldroyd-B type via the incompressible limit when the initial data are sufficiently small.
Runzhang, Xu; Yanbing, Yang; Bowei, Liu; Jihong, Shen; Shaobin, Huang
2015-06-01
This paper is concerned with the Cauchy problem of solutions for some nonlinear multidimensional "good" Boussinesq equation of sixth order at three different initial energy levels. In the framework of potential well, the global existence and blowup of solutions are obtained together with the concavity method at both low and critical initial energy level. Moreover by introducing a new stable set, we present some sufficient conditions on initial data such that the weak solution exists globally at supercritical initial energy level.
Global Existence of Weak Solutions to a Fractional Model in Magnetoelastic Interactions
Idriss Ellahiani
2016-01-01
Full Text Available The paper deals with global existence of weak solutions to a one-dimensional mathematical model describing magnetoelastic interactions. The model is described by a fractional Landau-Lifshitz-Gilbert equation for the magnetization field coupled to an evolution equation for the displacement. We prove global existence by using Faedo-Galerkin/penalty method. Some commutator estimates are used to prove the convergence of nonlinear terms.
Existence of local and global solutions to some impulsive fractional differential equation
Said Mazouzi
2009-10-01
Full Text Available First, by using Schauder's fixed-point theorem we establish the existence uniqueness of locals for some fractional differential equation with a finite number of impulses. On the other hand, by using Brouwer's fixed-point theorem, we establish existence of the global solutions under suitable assumptions.
Estimated global nitrogen deposition using NO2 column density
Lu, Xuehe; Jiang, Hong; Zhang, Xiuying; Liu, Jinxun; Zhang, Zhen; Jin, Jiaxin; Wang, Ying; Xu, Jianhui; Cheng, Miaomiao
2013-01-01
Global nitrogen deposition has increased over the past 100 years. Monitoring and simulation studies of nitrogen deposition have evaluated nitrogen deposition at both the global and regional scale. With the development of remote-sensing instruments, tropospheric NO2 column density retrieved from Global Ozone Monitoring Experiment (GOME) and Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) sensors now provides us with a new opportunity to understand changes in reactive nitrogen in the atmosphere. The concentration of NO2 in the atmosphere has a significant effect on atmospheric nitrogen deposition. According to the general nitrogen deposition calculation method, we use the principal component regression method to evaluate global nitrogen deposition based on global NO2 column density and meteorological data. From the accuracy of the simulation, about 70% of the land area of the Earth passed a significance test of regression. In addition, NO2 column density has a significant influence on regression results over 44% of global land. The simulated results show that global average nitrogen deposition was 0.34 g m−2 yr−1 from 1996 to 2009 and is increasing at about 1% per year. Our simulated results show that China, Europe, and the USA are the three hotspots of nitrogen deposition according to previous research findings. In this study, Southern Asia was found to be another hotspot of nitrogen deposition (about 1.58 g m−2 yr−1 and maintaining a high growth rate). As nitrogen deposition increases, the number of regions threatened by high nitrogen deposits is also increasing. With N emissions continuing to increase in the future, areas whose ecosystem is affected by high level nitrogen deposition will increase.
Uniform existence of the integrated density of states on metric Cayley graphs
Pogorzelski, Felix; Seifert, Christian
2011-01-01
Given a finitely generated amenable group we consider ergodic random Schr\\"odinger operators on a Cayley graph with random potentials and random boundary conditions. We show that the normalised eigenvalue counting functions of finite volume parts converge uniformly. The integrated density of states as the limit can be expressed by a Pastur-Shubin formula. The spectrum supports the corresponding measure and discontinuities correspond to the existence of compactly supported eigenfunctions.
Global existence result for phase transformations with heat transfer in shape memory alloys
Paoli, Laetitia
2011-01-01
We consider three-dimensional models for rate-independent processes describing materials undergoing phase transformations with heat transfer. The problem is formulated within the framework of generalized standard solids by the coupling of the momentum equilibrium equation and the flow rule with the heat transfer equation. Under appropriate regularity assumptions on the initial data, we prove the existence a global solution for this thermodynamically consistent system, by using a fixed-point argument combined with global energy estimates.
Global existence for semilinear wave equations with the critical blow-up term in high dimensions
Takamura, Hiroyuki; Wakasa, Kyouhei
2016-07-01
We are interested in almost global existence cases in the general theory for nonlinear wave equations, which are caused by critical exponents of nonlinear terms. Such situations can be found in only three cases in the theory, cubic terms in two space dimensions, quadratic terms in three space dimensions and quadratic terms including a square of unknown functions itself in four space dimensions. Except for the last case, criteria to classify nonlinear terms into the almost global, or global existence case, are well-studied and known to be so-called null condition and non-positive condition. Our motivation of this work is to find such a kind of the criterion in four space dimensions. In our previous paper, an example of the non-single term for the almost global existence case is introduced. In this paper, we show an example of the global existence case. These two examples have nonlinear integral terms which are closely related to derivative loss due to high dimensions. But it may help us to describe the final form of the criterion.
Global existence and blowup of solutions to a free boundary problem for mutualistic model
KIM; KwangIk
2010-01-01
This article is concerned with a system of semilinear parabolic equations with a free boundary,which arises in a mutualistic ecological model.The local existence and uniqueness of a classical solution are obtained.The asymptotic behavior of the free boundary problem is studied.Our results show that the free problem admits a global slow solution if the inter-specific competitions are strong,while if the inter-specific competitions are weak there exist the blowup solution and global fast solution.
无
2010-01-01
In this paper we investigate the two-dimensional compressible isentropic Euler equations for Chaplygin gases. Under the assumption that the initial data is close to a constant state and the vorticity of the initial velocity vanishes, we prove the global existence of the smooth solution to the Cauchy problem for twodimensional flow of Chaplygin gases.
Sharp Criterion of Global Existence for Nonlinear Schr(o)dinger Equation with a Harmonic Potential
Ji SHU; Jian ZHANG
2009-01-01
This paper discusses nonlinear Schr(o)dinger equation with a harmonic potential. By constructing a different cross-constrained variational problem and the so-called invariant sets, we derive a new threshold for blow-up and global existence of solutions.
Global existence of harmonic maps on Minkowski space time M/sub 3/
Choquet-Bruhat, Y.; Chao Hao, G.
1989-02-01
We prove the existence of global solutions of the Cauchy problem for harmonic maps from three dimensional Minkowski space time M/sub 3/ into some pseudo riemannian manifolds, including spaces with constant curvature, when the Cauchy data are small in appropriate norms.
Zhao Hongyong [Department of Mathematics, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)]. E-mail: hongyongz@126.com; Ding Nan [Department of Mathematics, Xinjiang Normal University, Urumqi 830054 (China)
2006-07-15
In this paper, Lotka-Volterra competition-predator system with variable delays is considered. Some sufficient conditions ensuring the existence and global attractivity of periodic solution for this system are obtained by using coincidence degree theory and Lyapunov functional method. An example is also worked out to demonstrate the advantages of our results.
Existence of global solution for a differential system with initial data in Lp
Peter Bates
1999-01-01
field within the earth. The system is similar to the magnetohydrodynamic (MHD equations. By establishing a new priori estimates and following Calderón's procedure for the Navier Stokes equations [1], we obtained, for initial data in space Lp, the global in time existence and uniqueness of weak solution of the system subject to appropriate conditions.
Existence of global weak solution for a reduced gravity two and a half layer model
Guo, Zhenhua, E-mail: zhenhua.guo.math@gmail.com; Li, Zilai, E-mail: lizilai0917@163.com; Yao, Lei, E-mail: yaolei1056@hotmail.com [Department of Mathematics and CNS, Northwest University, Xi' an 710127 (China)
2013-12-15
We investigate the existence of global weak solution to a reduced gravity two and a half layer model in one-dimensional bounded spatial domain or periodic domain. Also, we show that any possible vacuum state has to vanish within finite time, then the weak solution becomes a unique strong one.
Global Existence and Uniqueness of Strong Solutions for the Magnetohydrodynamic Equations
Jianwen Zhang
2008-02-01
Full Text Available This paper is concerned with an initial boundary value problem in one-dimensional magnetohydrodynamics. We prove the global existence, uniqueness, and stability of strong solutions for the planar magnetohydrodynamic equations for isentropic compressible fluids in the case that vacuum can be allowed initially.
Global Existence and Uniqueness of Strong Solutions for the Magnetohydrodynamic Equations
Zhang Jianwen
2008-01-01
Full Text Available This paper is concerned with an initial boundary value problem in one-dimensional magnetohydrodynamics. We prove the global existence, uniqueness, and stability of strong solutions for the planar magnetohydrodynamic equations for isentropic compressible fluids in the case that vacuum can be allowed initially.
Existence of global solutions to reaction-diffusion systems via a Lyapunov functional
Said Kouachi
2001-10-01
Full Text Available The purpose of this paper is to construct polynomial functionals (according to solutions of the coupled reaction-diffusion equations which give $L^{p}$-bounds for solutions. When the reaction terms are sufficiently regular, using the well known regularizing effect, we deduce the existence of global solutions. These functionals are obtained independently of work done by Malham and Xin [11].
Gerbi, Stéphane
2013-01-15
The goal of this work is to study a model of the wave equation with dynamic boundary conditions and a viscoelastic term. First, applying the Faedo-Galerkin method combined with the fixed point theorem, we show the existence and uniqueness of a local in time solution. Second, we show that under some restrictions on the initial data, the solution continues to exist globally in time. On the other hand, if the interior source dominates the boundary damping, then the solution is unbounded and grows as an exponential function. In addition, in the absence of the strong damping, then the solution ceases to exist and blows up in finite time.
Bie, Qunyi; Cui, Haibo; Wang, Qiru; Yao, Zheng-An
2017-10-01
The Cauchy problem for the compressible flow of nematic liquid crystals in the framework of critical spaces is considered. We first establish the existence and uniqueness of global solutions provided that the initial data are close to some equilibrium states. This result improves the work by Hu and Wu (SIAM J Math Anal 45(5):2678-2699, 2013) through relaxing the regularity requirement of the initial data in terms of the director field. Based on the global existence, we then consider the incompressible limit problem for ill prepared initial data. We prove that as the Mach number tends to zero, the global solution to the compressible flow of liquid crystals converges to the solution to the corresponding incompressible model in some function spaces. Moreover, the accurate converge rates are obtained.
Shuang Ping TAO; Shang Bin CUI
2005-01-01
This paper is devoted to studying the initial value problem of the modified nonlinear Kawahara equation ()u/()t+ a u2()u/()m + β()3u/()x3 + γ()5u-()x5 = 0, (x, t) ∈ We first establish several Strichartz type estimates for the fundamental solution of the corresponding linear problem. Then we apply such estimates to prove local and global existence of solutions for the initial value problem of the modified nonlinear Karahara equation. The results show that a local solution exists if the initial function u0(x) ∈ Hs(R) with s ≥ 1/4, and a global solution exists if s ≥ 2.
无
2006-01-01
Existence of globally bounded classical solution for nonisentropic gas dynamics system has long been studied, especially in the case of polytropic gas. In [4], Liu claimed that sufficient condition has been established. However, the authors find that the argument he used is not true in general. In this article, the authors give a counter example of his argument. Hence, his claim is not valid. The authors believe that it is difficult to impose general conditions on the initial data to obtain globally bounded classical solution.
Existence and regularity of a global attractor for doubly nonlinear parabolic equations
Abderrahmane El Hachimi
2002-05-01
Full Text Available In this paper we consider a doubly nonlinear parabolic partial differential equation $$ frac{partial eta (u}{partial t}-Delta _{p}u+f(x,t,u=0 quad hbox{in }Omega imesmathbb{R}^{+}, $$ with Dirichlet boundary condition and initial data given. We prove the existence of a global compact attractor by using a dynamical system approach. Under additional conditions on the nonlinearities $Beta$, $f$, and on $p$, we prove more regularity for the global attractor and obtain stabilization results for the solutions.
Tsunami Speed Variations in Density-stratified Compressible Global Oceans
Watada, S.
2013-12-01
Recent tsunami observations in the deep ocean have accumulated unequivocal evidence that tsunami traveltime delays compared with the linear long-wave tsunami simulations occur during tsunami propagation in the deep ocean. The delay is up to 2% of the tsunami traveltime. Watada et al. [2013] investigated the cause of the delay using the normal mode theory of tsunamis and attributed the delay to the compressibility of seawater, the elasticity of the solid earth, and the gravitational potential change associated with mass motion during the passage of tsunamis. Tsunami speed variations in the deep ocean caused by seawater density stratification is investigated using a newly developed propagator matrix method that is applicable to seawater with depth-variable sound speeds and density gradients. For a 4-km deep ocean, the total tsunami speed reduction is 0.45% compared with incompressible homogeneous seawater; two thirds of the reduction is due to elastic energy stored in the water and one third is due to water density stratification mainly by hydrostatic compression. Tsunami speeds are computed for global ocean density and sound speed profiles and characteristic structures are discussed. Tsunami speed reductions are proportional to ocean depth with small variations, except for in warm Mediterranean seas. The impacts of seawater compressibility and the elasticity effect of the solid earth on tsunami traveltime should be included for precise modeling of trans-oceanic tsunamis. Data locations where a vertical ocean profile deeper than 2500 m is available in World Ocean Atlas 2009. The dark gray area indicates the Pacific Ocean defined in WOA09. a) Tsunami speed variations. Red, gray and black bars represent global, Pacific, and Mediterranean Sea, respectively. b) Regression lines of the tsunami velocity reduction for all oceans. c)Vertical ocean profiles at grid points indicated by the stars in Figure 1.
Zhang Zhijiun
2008-01-01
By Karamata regular variation theory and constructing comparison functions, the author shows the existence and global optimal asymptotic behaviour of solutions for a semilinear elliptic problem △u = k(x)g(u),u>0, x∈Ω, u|(e)Ω = +∞, where Ω is a bounded domain with smooth boundary in RN; g ∈ C1[0,∞), g(0) = g'(0) = 0, and there exists p > 1, such that lims→∞ g(sξ)/g(s)=ξp, (A)ξ > 0, and k∈Cαloc(Ω) is non-negative non-trivial in Ω which may be singular on the boundary.
On the Global Existence and Uniqueness of Solutions to Prandtl's System
Xin Ying XU; Jun Ning ZHAO
2009-01-01
In this paper, we consider the Prandtl system for the non-stationary boundary layer in the vicinity of a point where the outer flow has zero velocity. It is assumed that U(t, x, y) = xmU1(t, x), where 0≤x≤L and m≥1. We establish the global existence of the weak solution to this problem. Moreover the uniqueness of the weak solution is proved.
Global existence and decay of solutions of the Cauchy problem in thermoelasticity with second sound
Kasimov, Aslan R.
2013-06-04
We consider the one-dimensional Cauchy problem in non-linear thermoelasticity with second sound, where the heat conduction is modelled by Cattaneo\\'s law. After presenting decay estimates for solutions to the linearized problem, including refined estimates for data in weighted Lebesgue-spaces, we prove a global existence theorem for small data together with improved decay estimates, in particular for derivatives of the solutions. © 2013 Taylor & Francis.
EXISTENCE OF GLOBAL SMOOTH SOLUTION TO JIN-XIN MODEL WITH LARGE INITIAL DATA
Ruan Lizhi; Zhang Zhiyong
2004-01-01
In this paper, Under the assumption that the relaxation time e is suf-ficiently small, we prove the existence of the global smooth solution to the Cauchyproblem for the Jin-Xin model without any smallness assumption for the initial data.The analysis is based on some a priori estimates which are obtained by the method ofcharacteristic and the maximum principle of first-order quasilinear hyperbolic system.
郭柏灵; 苗长兴
1995-01-01
The final value problem for the classical coupled Klein-Gordon-Schrodinger equations is studied in . This leads to the construction of the modified wave operator Ω, for certain scattered data. When initial functions belong to (Ω) which denotes the range domain of Ω, the global existence and asymptotic behavior of solutions of Cauchy problem tor the coupled Klein-Gordon-Schrodinger equations are proved.
Existence of global strong solutions for the shallow-water equations with large initial data
Haspot, Boris
2011-01-01
This work is devoted to the study of a viscous shallow-water system with friction and capillarity term. We prove in this paper the existence of global strong solutions for this system with some choice of large initial data when $N\\geq 2$ in critical spaces for the scaling of the equations. More precisely, we introduce as in \\cite{Hprepa} a new unknown,\\textit{a effective velocity} $v=u+\\mu\
Global existence of weak solution to the heat and moisture transport system in fibrous porous media
Li, Buyang; Wang, Yi
2009-01-01
This paper is concerned with theoretical analysis of a heat and moisture transfer model arising from textile industries, which is described by a degenerate and strongly coupled parabolic system. We prove the global (in time) existence of weak solution by constructing an approximate solution with some standard smoothing. The proof is based on the physcial nature of gas convection, in which the heat (energy) flux in convection is determined by the mass (vapor) flux in convection.
Wu Xuesong; Gao Wenjie; Cao Jianwen
2011-01-01
In this paper, the authors discuss the global existence and blow-up of the solution to an evolution ρ-Laplace system with nonlinear sources and nonlinear boundary condition. The authors first establish the local existence of solutions, then give a necessary and sufficient condition on the global existence of the positive solution.
Global Warming: Can Existing Reserves Really Preserve Current Levels of Biological Diversity?
无
2006-01-01
Paleoecological evidence and paleoclimatic records indicate that there was a plant poleward migration in latitude and an upward shift in elevation with increased temperatures after the last glaciation. Recent studies have shown that global warming over the past 100 years has been having a noticeable effect on living systems.Current global warming is causing a poleward and upward shift in the range of many plants and animals.Climate change, in connection with other global changes, is threatening the survival of a wide range of plant and animal species. This raises the question: can existing reserves really preserve current levels of biological diversity in the long term given the present rapid pace of climate change? The present paper deals with this question in the context of the responses of plants and animals to global climate change, based on a literature review. Consequently, we recommend expanding reserves towards the poles and/or towards higher altitudes,to permit species to shift their ranges to keep pace with global warming.
Bone mineral density in patients with growth hormone deficiency: does a gender difference exist?
Hitz, Mette Friberg; Jensen, Jens-Erik Beck; Eskildsen, Peter C
2006-01-01
OBJECTIVE: The aim of the study was to clarify whether a gender difference exists with respect to bone mineral density (BMD) and bone mineral content (BMC) in adult patients with growth hormone deficiency (GHD). DESIGN: A case-control design. METHODS: Blood sampling for measurements of calcium......, phosphate, creatinine, PTH, vitamin D, IGF-1, markers of bone formation and bone resorption, and dual energy X-ray absorptiometry (DEXA), to determine BMD and BMC of the lumbar spine, hip, distal arm and total body, were performed in 34 patients with GHD (19 females) and 34 sex-, age- and weight...... identical BMD values at all regions. This gender difference was even more obvious when BMD values were expressed as Z-scores or as three-dimensional BMD of the total body. The bone formation and bone resorption markers, as well as calcium and vitamin D, were all at the same levels in GH...
Bone Mineral Density in Patients with Growth Hormone Deficiency - Does a Gender Difference Exist?
Hitz, Mette; Jensen, Jens-Erik Beck; Eskildsen, PC
2006-01-01
OBJECTIVE: The aim of the study was to clarify whether a gender difference exists with respect to bone mineral density (BMD) and bone mineral content (BMC) in adult patients with growth hormone deficiency (GHD). DESIGN: A case-control design. METHODS: Blood sampling for measurements of calcium......, phosphate, creatinine, PTH, vitamin D, IGF-1, markers of bone formation and bone resorption, and dual energy X-ray absorptiometry (DEXA), to determine BMD and BMC of the lumbar spine, hip, distal arm and total body, were performed in 34 patients with GHD (19 females) and 34 sex-, age- and weight...... identical BMD values at all regions. This gender difference was even more obvious when BMD values were expressed as Z-scores or as three-dimensional BMD of the total body. The bone formation and bone resorption markers, as well as calcium and vitamin D, were all at the same levels in GH...
Bone Mineral Density in Patients with Growth Hormone Deficiency - Does a Gender Difference Exist?
Hitz, Mette; Jensen, Jens-Erik Beck; Eskildsen, PC
2006-01-01
OBJECTIVE: The aim of the study was to clarify whether a gender difference exists with respect to bone mineral density (BMD) and bone mineral content (BMC) in adult patients with growth hormone deficiency (GHD). DESIGN: A case-control design. METHODS: Blood sampling for measurements of calcium......, phosphate, creatinine, PTH, vitamin D, IGF-1, markers of bone formation and bone resorption, and dual energy X-ray absorptiometry (DEXA), to determine BMD and BMC of the lumbar spine, hip, distal arm and total body, were performed in 34 patients with GHD (19 females) and 34 sex-, age- and weight...... identical BMD values at all regions. This gender difference was even more obvious when BMD values were expressed as Z-scores or as three-dimensional BMD of the total body. The bone formation and bone resorption markers, as well as calcium and vitamin D, were all at the same levels in GH...
Bone mineral density in patients with growth hormone deficiency: does a gender difference exist?
Hitz, Mette Friberg; Jensen, Jens-Erik Beck; Eskildsen, Peter C
2006-01-01
OBJECTIVE: The aim of the study was to clarify whether a gender difference exists with respect to bone mineral density (BMD) and bone mineral content (BMC) in adult patients with growth hormone deficiency (GHD). DESIGN: A case-control design. METHODS: Blood sampling for measurements of calcium......, phosphate, creatinine, PTH, vitamin D, IGF-1, markers of bone formation and bone resorption, and dual energy X-ray absorptiometry (DEXA), to determine BMD and BMC of the lumbar spine, hip, distal arm and total body, were performed in 34 patients with GHD (19 females) and 34 sex-, age- and weight...... identical BMD values at all regions. This gender difference was even more obvious when BMD values were expressed as Z-scores or as three-dimensional BMD of the total body. The bone formation and bone resorption markers, as well as calcium and vitamin D, were all at the same levels in GH...
Uniform existence of the integrated density of states for models on Z^d
Gruber, Michael J; VeseliÄ, Ivan
2007-01-01
We give an overview and extension of recent results on ergodic random Schr\\"odinger operators for models on $\\mathbb{Z}^d$. The operators we consider are defined on combinatorial or metric graphs, with random potentials, random boundary conditions and random metrics taking values in a finite set. We show that normalized finite volume eigenvalue counting functions converge to a limit uniformly in the energy variable, at least locally. This limit, the integrated density of states (IDS), can be expressed by a closed Shubin-Pastur type trace formula. The set of points of increase of the IDS supports the spectrum and its points of discontinuity are characterized by existence of compactly supported eigenfunctions. This applies to several examples, including various periodic operators and percolation models.
Simple models for complex systems: exploiting the relationship between local and global densities.
Pascual, Mercedes; Roy, Manojit; Laneri, Karina
2011-01-01
Simple temporal models that ignore the spatial nature of interactions and track only changes in mean quantities, such as global densities, are typically used under the unrealistic assumption that individuals are well mixed. These so-called mean-field models are often considered overly simplified, given the ample evidence for distributed interactions and spatial heterogeneity over broad ranges of scales. Here, we present one reason why such simple population models may work even when mass-action assumptions do not hold: spatial structure is present but it relates to global densities in a special way. With an individual-based predator-prey model that is spatial and stochastic, and whose mean-field counterpart is the classic Lotka-Volterra model, we show that the global densities and densities of pairs (or spatial covariances) establish a bi-power law at the stationary state and also in their transient approach to this state. This relationship implies that the dynamics of global densities can be written simply as a function of those densities alone without invoking pairs (or higher order moments). The exponents of the bi-power law for the predation rate exhibit a remarkable robustness to changes in model parameters. Evidence is presented for a connection of our findings to the existence of a critical phase transition in the dynamics of the spatial system. We discuss the application of similar modified mean-field equations to other ecological systems for which similar transitions have been described, both in models and empirical data.Electronic supplementary material The online version of this article (doi:10.1007/s12080-011-0116-2) contains supplementary material, which is available to authorized users.
Existence of a virtual cathode close to a strongly electron emissive wall in low density plasmas
Tierno, S. P., E-mail: sp.tierno@upm.es; Donoso, J. M.; Domenech-Garret, J. L.; Conde, L. [Department of Applied Physics, E.T.S.I. Aeronáutica y del Espacio. Universidad Politécnica de Madrid, 28040 Madrid (Spain)
2016-01-15
The interaction between an electron emissive wall, electrically biased in a plasma, is revisited through a simple fluid model. We search for realistic conditions of the existence of a non-monotonic plasma potential profile with a virtual cathode as it is observed in several experiments. We mainly focus our attention on thermionic emission related to the operation of emissive probes for plasma diagnostics, although most conclusions also apply to other electron emission processes. An extended Bohm criterion is derived involving the ratio between the two different electron densities at the potential minimum and at the background plasma. The model allows a phase-diagram analysis, which confirms the existence of the non-monotonic potential profiles with a virtual cathode. This analysis shows that the formation of the potential well critically depends on the emitted electron current and on the velocity at the sheath edge of cold ions flowing from the bulk plasma. As a consequence, a threshold value of the governing parameter is required, in accordance to the physical nature of the electron emission process. The latter is a threshold wall temperature in the case of thermionic electrons. Experimental evidence supports our numerical calculations of this threshold temperature. Besides this, the potential well becomes deeper with increasing electron emission, retaining a fraction of the released current which limits the extent of the bulk plasma perturbation. This noninvasive property would explain the reliable measurements of plasma potential by using the floating potential method of emissive probes operating in the so-called strong emission regime.
A review of existing and emerging digital technologies to combat the global trade in fake medicines.
Mackey, Tim K; Nayyar, Gaurvika
2017-05-01
The globalization of the pharmaceutical supply chain has introduced new challenges, chief among them, fighting the international criminal trade in fake medicines. As the manufacture, supply, and distribution of drugs becomes more complex, so does the need for innovative technology-based solutions to protect patients globally. Areas covered: We conducted a multidisciplinary review of the science/health, information technology, computer science, and general academic literature with the aim of identifying cutting-edge existing and emerging 'digital' solutions to combat fake medicines. Our review identified five distinct categories of technology including mobile, radio frequency identification, advanced computational methods, online verification, and blockchain technology. Expert opinion: Digital fake medicine solutions are unifying platforms that integrate different types of anti-counterfeiting technologies as complementary solutions, improve information sharing and data collection, and are designed to overcome existing barriers of adoption and implementation. Investment in this next generation technology is essential to ensure the future security and integrity of the global drug supply chain.
Existence of global strong solutions to a beam-fluid interaction system
Grandmont, C
2015-01-01
We study an unsteady non linear fluid-structure interaction problem which is a simplified model to describe blood flow through viscoleastic arteries. We consider a Newtonian incompressible two-dimensional flow described by the Navier-Stokes equations set in an unknown domain depending on the displacement of a structure, which itself satisfies a linear viscoelastic beam equation. The fluid and the structure are fully coupled via interface conditions prescribing the continuity of the velocities at the fluid-structure interface and the action-reaction principle. We prove that strong solutions to this problem are global-in-time. We obtain in particular that contact between the viscoleastic wall and the bottom of the fluid cavity does not occur in finite time. To our knowledge, this is the first occurrence of a no-contact result, but also of existence of strong solutions globally in time, in the frame of interactions between a viscous fluid and a deformable structure.
The global existence of Yang-Mills fields on curved space-times
Ghanem, Sari
2013-01-01
This is an introductory chapter in a series in which we take a systematic study of the Yang-Mills equations on curved space-times. In this first, we provide standard material that consists in writing the proof of the global existence of Yang-Mills fields on arbitrary curved space-times using the Klainerman-Rodnianski parametrix combined with suitable Gr\\"onwall type inequalities. While the Chru\\'sciel-Shatah argument requires a simultaneous control of the $L^{\\infty}_{loc}$ and the $H^{2}_{loc}$ norms of the Yang-Mills curvature, we can get away by controlling only the $H^{1}_{loc}$ norm instead, and write a new gauge independent proof on arbitrary, fixed, sufficiently smooth, globally hyperbolic, curved 4-dimensional Lorentzian manifolds. This manuscript is written in an expository way in order to provide notes to Master's level students willing to learn mathematical General Relativity.
Zheng, Xiao; Yam, ChiYung; Wang, Fan; Chen, GuanHua
2011-08-28
We present the time-dependent holographic electron density theorem (TD-HEDT), which lays the foundation of time-dependent density-functional theory (TDDFT) for open electronic systems. For any finite electronic system, the TD-HEDT formally establishes a one-to-one correspondence between the electron density inside any finite subsystem and the time-dependent external potential. As a result, any electronic property of an open system in principle can be determined uniquely by the electron density function inside the open region. Implications of the TD-HEDT on the practicality of TDDFT are also discussed.
Global and local curvature in density functional theory
Zhao, Qing; Ioannidis, Efthymios I.; Kulik, Heather J.
2016-08-01
Piecewise linearity of the energy with respect to fractional electron removal or addition is a requirement of an electronic structure method that necessitates the presence of a derivative discontinuity at integer electron occupation. Semi-local exchange-correlation (xc) approximations within density functional theory (DFT) fail to reproduce this behavior, giving rise to deviations from linearity with a convex global curvature that is evidence of many-electron, self-interaction error and electron delocalization. Popular functional tuning strategies focus on reproducing piecewise linearity, especially to improve predictions of optical properties. In a divergent approach, Hubbard U-augmented DFT (i.e., DFT+U) treats self-interaction errors by reducing the local curvature of the energy with respect to electron removal or addition from one localized subshell to the surrounding system. Although it has been suggested that DFT+U should simultaneously alleviate global and local curvature in the atomic limit, no detailed study on real systems has been carried out to probe the validity of this statement. In this work, we show when DFT+U should minimize deviations from linearity and demonstrate that a "+U" correction will never worsen the deviation from linearity of the underlying xc approximation. However, we explain varying degrees of efficiency of the approach over 27 octahedral transition metal complexes with respect to transition metal (Sc-Cu) and ligand strength (CO, NH3, and H2O) and investigate select pathological cases where the delocalization error is invisible to DFT+U within an atomic projection framework. Finally, we demonstrate that the global and local curvatures represent different quantities that show opposing behavior with increasing ligand field strength, and we identify where these two may still coincide.
Evidence of the existence of the low-density liquid phase in supercooled, confined water.
Mallamace, Francesco; Broccio, Matteo; Corsaro, Carmelo; Faraone, Antonio; Majolino, Domenico; Venuti, Valentina; Liu, Li; Mou, Chung-Yuan; Chen, Sow-Hsin
2007-01-09
By confining water in a nanoporous structure so narrow that the liquid could not freeze, it is possible to study properties of this previously undescribed system well below its homogeneous nucleation temperature TH = 231 K. Using this trick, we were able to study, by means of a Fourier transform infrared spectroscopy, vibrational spectra (HOH bending and OH-stretching modes) of deeply supercooled water in the temperature range 183 < T < 273 K. We observed, upon decreasing temperature, the building up of a new population of hydrogen-bonded oscillators centered around 3,120 cm(-1), the contribution of which progressively dominates the spectra as one enters into the deeply supercooled regime. We determined that the fractional weight of this spectral component reaches 50% just at the temperature, TL approximately 225 K, where the confined water shows a fragile-to-strong dynamic cross-over phenomenon [Ito, K., Moynihan, C. T., Angell, C. A. (1999) Nature 398:492-494]. Furthermore, the fact that the corresponding OH stretching spectral peak position of the low-density-amorphous solid water occurs exactly at 3,120 cm(-1) [Sivakumar, T. C., Rice, S. A., Sceats, M. G. (1978) J. Chem. Phys. 69:3468-3476.] strongly suggests that these oscillators originate from existence of the low-density-liquid phase derived from the occurrence of the first-order liquid-liquid (LL) phase transition and the associated LL critical point in supercooled water proposed earlier by a computer molecular dynamics simulation [Poole, P. H., Sciortino, F., Essmann, U., Stanley, H. E. (1992) Nature 360:324-328].
Critical Blow-Up and Global Existence for Discrete Nonlinear p-Laplacian Parabolic Equations
Soon-Yeong Chung
2014-01-01
Full Text Available The goal of this paper is to investigate the blow-up and the global existence of the solutions to the discrete p-Laplacian parabolic equation utx,t=Δp,wux,t+λux,tp-2ux,t, x,t∈S×0,∞, ux,t=0, x,t∈∂S×0,∞, ux,0=u0, depending on the parameters p>1 and λ>0. Besides, we provide several types of the comparison principles to this equation, which play a key role in the proof of the main theorems. In addition, we finally give some numerical examples which exploit the main results.
Kim, Daewook; Kim, Dojin; Hong, Keum-Shik; Jung, Il Hyo
2014-01-01
The first objective of this paper is to prove the existence and uniqueness of global solutions for a Kirchhoff-type wave equation with nonlinear dissipation of the form Ku'' + M(|A (1/2) u|(2))Au + g(u') = 0 under suitable assumptions on K, A, M(·), and g(·). Next, we derive decay estimates of the energy under some growth conditions on the nonlinear dissipation g. Lastly, numerical simulations in order to verify the analytical results are given.
Huang Zhenkun [Department of Mathematics, School of Sciences, Zhejiang University, Hangzhou, Zhejiang 310027 (China) and School of Sciences, Jimei University, Xiamen, Fujian 361021 (China)]. E-mail: huangdoc@tom.com; Wang Xinghua [Department of Mathematics, School of Sciences, Zhejiang University, Hangzhou, Zhejiang 310027 (China); Gao Feng [School of Sciences, Jimei University, Xiamen, Fujian 361021 (China)
2006-02-06
In this Letter, we discuss discrete-time analogue of a continuous-time cellular neural network. Sufficient conditions are obtained for the existence of a unique almost periodic sequence solution which is globally attractive. Our results demonstrate dynamics of the formulated discrete-time analogue as mathematical models for the continuous-time cellular neural network in almost periodic case. Finally, a computer simulation illustrates the suitability of our discrete-time analogue as numerical algorithms in simulating the continuous-time cellular neural network conveniently.
Existence and uniqueness of global solutions for the modified anisotropic 3D Navier−Stokes equations
Bessaih, Hakima
2016-01-27
We study a modified three-dimensional incompressible anisotropic Navier−Stokes equations. The modification consists in the addition of a power term to the nonlinear convective one. This modification appears naturally in porous media when a fluid obeys the Darcy−Forchheimer law instead of the classical Darcy law. We prove global in time existence and uniqueness of solutions without assuming the smallness condition on the initial data. This improves the result obtained for the classical 3D incompressible anisotropic Navier−Stokes equations.
Bresch, Didier
2015-01-01
We prove global existence of appropriate weak solutions for the compressible Navier--Stokes equations for more general stress tensor than those covered by P.-L. Lions and E. Feireisl's theory. More precisely we focus on more general pressure laws which are not thermodynamically stable; we are also able to handle some anisotropy in the viscous stress tensor. To give answers to these two longstanding problems, we revisit the classical compactness theory on the density by obtaining precise quantitative regularity estimates: This requires a more precise analysis of the structure of the equations combined to a novel approach to the compactness of the continuity equation. These two cases open the theory to important physical applications, for instance to describe solar events (virial pressure law), geophysical flows (eddy viscosity) or biological situations (anisotropy).
张映辉; 吴国春
2014-01-01
We investigate the global existence and asymptotic behavior of classical solutions for the 3D compressible non-isentropic damped Euler equations on a periodic domain. The global existence and uniqueness of classical solutions are obtained when the initial data is near an equilibrium. Furthermore, the exponential convergence rates of the pressure and velocity are also proved by delicate energy methods.
Ruggenthaler, Michael; Penz, Markus; van Leeuwen, Robert
2015-05-27
In this work we review the mapping from densities to potentials in quantum mechanics, which is the basic building block of time-dependent density-functional theory and the Kohn-Sham construction. We first present detailed conditions such that a mapping from potentials to densities is defined by solving the time-dependent Schrödinger equation. We specifically discuss intricacies connected with the unboundedness of the Hamiltonian and derive the local-force equation. This equation is then used to set up an iterative sequence that determines a potential that generates a specified density via time propagation of an initial state. This fixed-point procedure needs the invertibility of a certain Sturm-Liouville problem, which we discuss for different situations. Based on these considerations we then present a discussion of the famous Runge-Gross theorem which provides a density-potential mapping for time-analytic potentials. Further we give conditions such that the general fixed-point approach is well-defined and converges under certain assumptions. Then the application of such a fixed-point procedure to lattice Hamiltonians is discussed and the numerical realization of the density-potential mapping is shown. We conclude by presenting an extension of the density-potential mapping to include vector-potentials and photons.
Tracking the global generation and exports of e-waste. Do existing estimates add up?
Breivik, Knut; Armitage, James M; Wania, Frank; Jones, Kevin C
2014-01-01
The transport of discarded electronic and electrical appliances (e-waste) to developing regions has received considerable attention, but it is difficult to assess the significance of this issue without a quantitative understanding of the amounts involved. The main objective of this study is to track the global transport of e-wastes by compiling and constraining existing estimates of the amount of e-waste generated domestically in each country MGEN, exported from countries belonging to the Organization for Economic Cooperation and Development (OECD) MEXP, and imported in countries outside of the OECD MIMP. Reference year is 2005 and all estimates are given with an uncertainty range. Estimates of MGEN obtained by apportioning a global total of ∼ 35,000 kt (range 20,000-50,000 kt) based on a nation's gross domestic product agree well with independent estimates of MGEN for individual countries. Import estimates MIMP to the countries believed to be the major recipients of e-waste exports from the OECD globally (China, India, and five West African countries) suggests that ∼ 5,000 kt (3,600 kt-7,300 kt) may have been imported annually to these non-OECD countries alone, which represents ∼ 23% (17%-34%) of the amounts of e-waste generated domestically within the OECD. MEXP for each OECD country is then estimated by applying this fraction of 23% to its MGEN. By allocating each country's MGEN, MIMP, MEXP and MNET = MGEN + MIMP - MEXP, we can map the global generation and flows of e-waste from OECD to non-OECD countries. While significant uncertainties remain, we note that estimated import into seven non-OECD countries alone are often at the higher end of estimates of exports from OECD countries.
Ovarian cancer: density equalizing mapping of the global research architecture.
Brüggmann, Dörthe; Pulch, Katharina; Klingelhöfer, Doris; Pearce, Celeste Leigh; Groneberg, David A
2017-01-13
Despite its impact on female health worldwide, no efforts have been made to depict the global architecture of ovarian cancer research and to understand the trends in the related literature. Hence, it was the objective of this study to assess the global scientific performance chronologically, geographically and in regards to economic benchmarks using bibliometric tools and density equalizing map projections. The NewQIS platform was employed to identify all ovarian cancer related articles published in the Web of Science since 1900. The items were analyzed regarding quantitative aspects (e.g. publication date, country of origin) and parameters describing the recognition of the work by the scientific community (e.g. citation rates). 23,378 articles on ovarian cancer were analyzed. The USA had the highest activity of ovarian cancer research with a total of n = 9312 ovarian cancer-specific publications, followed by the UK (n = 1900), China (n = 1813), Germany (n = 1717) and Japan (n = 1673). Ovarian cancer-specific country h-index also showed a leading position of the USA with an h-index (HI) of 207, followed by the UK (HI = 122), Canada (HI = 99), Italy (HI = 97), Germany (HI = 84), and Japan (HI = 81). In the socio-economic analysis, the USA were ranked first with an average of 175.6 ovarian cancer-related publications per GDP per capita in 1000 US-$, followed by Italy with an index level of 46.85, the UK with 45.48, and Japan with 43.3. Overall, the USA and Western European nations, China and Japan constituted the scientific power players publishing the majority of highly cited ovarian cancer-related articles and dominated international collaborative efforts. African, Asian and South American countries played almost no visible role in the scientific community. The quantity and scientific recognition of publications related to ovarian cancer are continuously increasing. The research endeavors in the field are concentrated in high-income countries
Lee, Juyong; Lee, Jooyoung; Brooks, Bernard R; Ahn, Yong-Yeol
2016-01-01
We investigate the possibility of global optimization-based overlapping community detection, using link community framework. We first show that partition density, the original quality function used in link community detection method, is not suitable as a quality function for global optimization because it prefers breaking communities into triangles except in highly limited conditions. We analytically derive those conditions and confirm it with computational results on direct optimization of various synthetic and real-world networks. To overcome this limitation, we propose alternative approaches combining the weighted line graph transformation and existing quality functions for node-based communities. We suggest a new line graph weighting scheme, a normalized Jaccard index. Computational results show that community detection using the weighted line graphs generated with the normalized Jaccard index leads to a more accurate community structure.
Global existence and asymptotic stability of equilibria to reaction-diffusion systems
Wang, Rong-Nian; Tang, Zhong Wei
2009-06-01
In this paper, we study weakly coupled reaction-diffusion systems in unbounded domains of {\\bb R}^2 or {\\bb R}^3 , where the reaction terms are sums of quasimonotone nondecreasing and nonincreasing functions. Such systems are more complicated than those in many previous publications and little is known about them. A comparison principle and global existence, and boundedness theorems for solutions to these systems are established. Sufficient conditions on the nonlinearities, ensuring the positively Ljapunov stability of the zero solution with respect to H2-perturbations, are also obtained. As samples of applications, these results are applied to an autocatalytic chemical model and a concrete problem, whose nonlinearities are nonquasimonotone. Our results are novel. In particular, we present a solution to an open problem posed by Escher and Yin (2005 J. Nonlinear Anal. Theory Methods Appl. 60 1065-84).
Global existence of solutions to a tear film model with locally elevated evaporation rates
Gao, Yuan; Ji, Hangjie; Liu, Jian-Guo; Witelski, Thomas P.
2017-07-01
Motivated by a model proposed by Peng et al. (2014) for break-up of tear films on human eyes, we study the dynamics of a generalized thin film model. The governing equations form a fourth-order coupled system of nonlinear parabolic PDEs for the film thickness and salt concentration subject to non-conservative effects representing evaporation. We analytically prove the global existence of solutions to this model with mobility exponents in several different ranges and present numerical simulations that are in agreement with the analytic results. We also numerically capture other interesting dynamics of the model, including finite-time rupture-shock phenomenon due to the instabilities caused by locally elevated evaporation rates, convergence to equilibrium and infinite-time thinning.
Daskalopoulos, Panagiota
2011-01-01
The Heston stochastic volatility process, which is widely used as an asset price model in mathematical finance, is a paradigm for a degenerate diffusion process where the degeneracy in the diffusion coefficient is proportional to the square root of the distance to the boundary of the half-plane. The generator of this process with killing, called the elliptic Heston operator, is a second-order degenerate elliptic partial differential operator whose coefficients have linear growth in the spatial variables and where the degeneracy in the operator symbol is proportional to the distance to the boundary of the half-plane. With the aid of weighted Sobolev spaces, we prove existence, uniqueness, and global regularity of solutions to stationary variational inequalities and obstacle problems for the elliptic Heston operator on unbounded subdomains of the half-plane. In mathematical finance, solutions to obstacle problems for the elliptic Heston operator correspond to value functions for perpetual American-style options...
Existence for a global pressure formulation of water-gas flow in porous media
Brahim Amaziane
2012-06-01
Full Text Available We consider a model of water-gas flow in porous media with an incompressible water phase and a compressible gas phase. Such models appear in gas migration through engineered and geological barriers for a deep repository for radioactive waste. The main feature of this model is the introduction of a new global pressure and it is fully equivalent to the original equations. The system is written in a fractional flow formulation as a degenerate parabolic system with the global pressure and the saturation potential as the main unknowns. The major difficulties related to this model are in the nonlinear degenerate structure of the equations, as well as in the coupling in the system. Under some realistic assumptions on the data, including unbounded capillary pressure function and non-homogeneous boundary conditions, we prove the existence of weak solutions of the system. Furthermore, it is shown that the weak solution has certain desired properties, such as positivity of the saturation. The result is proved with the help of an appropriate regularization and a time discretization of the coupled system. We use suitable test functions to obtain a priori estimates and a compactness result in order to pass to the limit in nonlinear terms.
Shuang Ping TAO; Shang Bin CUI
2005-01-01
This paper is devoted to studying the initial value problems of the nonlinear KaupKupershmidt equations (e)u/(e)t + α1u(e)2u/(e)x2+β(e)3u/(e)x3+γ(e)5u/( )x5= 0, (x, t) ∈ R2, and (e)u/(e)t+α2 (e)u/(e)x (e)2u/(e)x2+β(e)3u/(e)x3+γ(e)5u/(e)x5 = 0, (x, t) ∈R2. Several important Strichartz type estimates for the fundamental solution of the corresponding linear problem are established. Then we apply such estimates to prove the local and global existence of solutions for the initial value problems of the nonlinear Kaup-Kupershmidt equations. The results show that a local solution exists if the initial function u0(x) ∈ Hs(R), and s ≥ 5/4 for the first equation and s ≥ 301/108 for the second equation.
Chengyuan Qu; Yang Cao
2013-11-01
We consider a class of nonlinear viscous Cahn–Hilliard equations with gradient dependent potentials and sources. By a Galerkin approximation scheme combined with the potential well method, we prove the global existence of weak solutions.
A note on the global existence of small amplitude solutions to a generalized Davey-Stewartson system
Eden, Alp [Department of Mathematics, Bogazici University, 34342 Bebek-Istanbul (Turkey); Hacinliyan, Irma [Department of Mathematics, Istanbul Technical University, 34469 Maslak-Istanbul (Turkey)], E-mail: hacinliy@itu.edu.tr
2009-06-19
In this paper, we are interested in the Cauchy problem for a generalized Davey-Stewartson (GDS) system. We establish the global time existence of small mass solutions for the GDS system in the elliptic-hyperbolic-hyperbolic case.
无
2001-01-01
The existence of positive solutions and the global attractivity of the difference equation △yn=rnyn are investigated. And some sufficient conditions are obtained,which greatly improve and extend the known results.
Wang, Wei; Wang, Xiangyuan; Lv, Yanping; Wang, Shufeng; Wang, Kai; Shi, Yantao; Xiao, Lixin; Chen, Zhijian; Gong, Qihuang
2016-01-01
Using transient fluorescent spectra at time-zero, we develop a density-resolved fluorescent spectroscopic method for investigating photoproducts in CH3NH3PbI3 perovskite and related photophysics. The density dependent dynamical co-existence of excitons and free carriers over a wide density range is experimentally observed for the first time. The exciton binding energy (EB) and the effective mass of electron-hole pair can be estimated based on such co-existence. No ionic polarization is found contributing to photophysical behavior. It also solves the conflict between the large experimentally measured EB and the small predicted values. The spectroscopic method also helps to detect the true free carrier density under continuous illumination without the interference of ionic conductivity. Our methods and results profoundly enrich the study and understanding of the photophysics in perovskite materials for photovoltaic applications.
Wu, Sainan; Shi, Junping; Wu, Boying
2016-04-01
This paper proves the global existence and boundedness of solutions to a general reaction-diffusion predator-prey system with prey-taxis defined on a smooth bounded domain with no-flux boundary condition. The result holds for domains in arbitrary spatial dimension and small prey-taxis sensitivity coefficient. This paper also proves the existence of a global attractor and the uniform persistence of the system under some additional conditions. Applications to models from ecology and chemotaxis are discussed.
Dao Yuan FANG; Ru Ying XUE
2006-01-01
In this paper, we consider a system of two cubic quasi-linear Klein-Gordon equations with different masses for small, smooth, compactly supported Cauchy data in one space dimension. We show that such a system has global existence when the nonlinearities satisfy a convenient null condition. Our results extend the global existence proved by Sunagawa recently under the non-resonance assumption to that under the resonance assumption.
Markowich, Peter
2010-06-01
We study the system ct + u · ∇c = ∇c -nf(c) nt + u · ∇n = ∇n m - ∇ · (n×(c) ∇c) ut + u·∇u + ∇P - η∇u + n∇φ/ = 0 ∇·u = 0. arising in the modelling of the motion of swimming bacteria under the effect of diffusion, oxygen-taxis and transport through an incompressible fluid. The novelty with respect to previous papers in the literature lies in the presence of nonlinear porous-medium-like diffusion in the equation for the density n of the bacteria, motivated by a finite size effect. We prove that, under the constraint m ε (3/2, 2] for the adiabatic exponent, such system features global in time solutions in two space dimensions for large data. Moreover, in the case m = 2 we prove that solutions converge to constant states in the large-time limit. The proofs rely on standard energy methods and on a basic entropy estimate which cannot be achieved in the case m = 1. The case m = 2 is very special as we can provide a Lyapounov functional. We generalize our results to the three-dimensional case and obtain a smaller range of exponents m ε (m*, 2] with m* > 3/2, due to the use of classical Sobolev inequalities.
Global existence for a hydrogen storage model with full energy balance
Bonetti, Elena; Laurençot, Philippe
2011-01-01
A thermo-mechanical model describing hydrogen storage by use of metal hydrides has been recently proposed in a paper by Bonetti, Fr\\'emond and Lexcellent. It describes the formation of hydrides using the phase transition approach. By virtue of the laws of continuum thermo-mechanics, the model leads to a phase transition problem in terms of three state variables: the temperature, the phase parameter representing the fraction of one solid phase, and the pressure, and is derived within a generalization of the principle of virtual powers proposed by Fr\\'emond accounting for micro-forces, responsible for the phase transition, in the whole energy balance of the system. Three coupled nonlinear partial differential equations combined with initial and boundary conditions have to be solved. The main difficulty in investigating the resulting system of partial differential equations relies on the presence of the squared time derivative of the order parameter in the energy balance equation. Here, the global existence of a...
Kunze, Markus
2011-01-01
We prove convergence of the solutions X_n of semilinear stochastic evolution equations dX_n(t) = (A_nX(t) + F_n(t,X_n(t)))dt + G_n(t,X_n(t))dW_H(t), X_n(0) = x_n, on a Banach space B, driven by a cylindrical Brownian motion W_H in a Hilbert space H. We assume that the operators A_n converge to A and the locally Lipschitz functions F_n and G_n converge to the locally Lipschitz functions F and G in an appropriate sense. Moreover, we obtain estimates for the lifetime of the solution X of the limiting problem in terms of the lifetimes of the approximating solutions X_n. We apply the results to prove global existence for reaction diffusion equations with multiplicative noise and a polynomially bounded reaction term satisfying suitable dissipativity conditions. The operator governing the linear part of the equation can be an arbitrary uniformly elliptic second order elliptic operator.
Afanasjev, A V
2015-01-01
The assessment of the global performance of the state-of-the-art covariant energy density functionals and related theoretical uncertainties in the description of ground state observables has recently been performed. Based on these results, the correlations between global description of binding energies and nuclear matter properties of covariant energy density functionals have been studied in this contribution.
Endometriosis and its global research architecture: an in-depth density-equalizing mapping analysis.
Brüggmann, Dörthe; Elizabeth-Martinez, Alexandra; Klingelhöfer, Doris; Quarcoo, David; Jaque, Jenny M; Groneberg, David A
2016-09-21
Endometriosis is one of the most common gynecological diseases. It is still a chameleon in many aspects and urges intense research activities in the fields of diagnosis, therapy and prevention. Despite the need to foster research in this area, no in-depth analysis of the global architecture of endometriosis research exists yet. We here used the NewQIS platform to conduct a density equalizing mapping study, using the Web of Science as database with endometriosis related entries between 1900 and 2009. Density equalizing maps of global endometriosis research encompassing country-specific publication activities, and semi-qualitative indices such as country specific citations, citation rates, h-Indices were created. In total, 11,056 entries related to endometriosis were found. The USA was leading the field with 3705 publications followed by the United Kingdom (952) and Japan (846). Concerning overall citations and country-specific h-Indices, the USA again was the leading nation with 74,592 citations and a modified h-Index of 103, followed by the UK with 15,175 citations (h-Index 57). Regarding the citation rate, Sweden and Belgium were at top positions with rates of 22.46 and 22.26, respectively. Concerning collaborative studies, there was a steep increase in numbers present; analysis of the chronological evolution indicated a strong increase in international collaborations in the past 10 years. This study is the first analysis that illustrates the global endometriosis research architecture. It shows that endometriosis research is constantly gaining importance but also underlines the need for further efforts and investments to foster research and ultimately improve endometriosis management on a global scale.
The Co-Existence of Globalism and Tribalism: A Review of the Literature
Karim, Sameena
2012-01-01
This critical literature review argues that, in a world of increasing global interconnectedness, balancing the two diametrically opposite forces of globalism and tribalism is of critical importance. The article begins with a brief description of the world of the 21st century and goes on to discuss the terms "globalism" and "tribalism" within this…
Junping YIN; Zhong TAN
2008-01-01
The authors prove two global existence results of strong solutions of the isen- tropic compressible Navier-Stokes-Poisson equations in one-dimensional bounded intervals. The first result shows only the existence. And the second one shows the existence and uniqueness result based on the first result, but the uniqueness requires some compatibility condition. In this paper the initial vacuum is allowed, and T is bounded.
Cordier, S.
1995-05-01
In this work a 1-D model of electrons and ions plasma is considered. Electrons are supposed to be in Maxwell-Boltzmann thermodynamic equilibrium while ions are described with an isothermal flow model of charged particles submitted to a self-consistent electric field. A collision term between neutral particles and ions simulates the presence of neutral particles. This work demonstrates the existence of low entropy solutions for this simple model with arbitrary initial conditions. Most of the paper is devoted to the demonstration of this theorem and follows the successive steps: construction of a numerical scheme, recall of the classical properties of Riemann problem solutions using Glimm method, uniform estimations for the whole variation norm, and finally, convergence of the constructed solutions towards a low entropy solution for the non-linear Euler/Poisson system. Domains of application for this type of model are listed in the conclusion. (J.S.). 18 refs.
Haspot, Boris
2016-06-01
We consider the compressible Navier-Stokes equations for viscous and barotropic fluids with density dependent viscosity. The aim is to investigate mathematical properties of solutions of the Navier-Stokes equations using solutions of the pressureless Navier-Stokes equations, that we call quasi solutions. This regime corresponds to the limit of highly compressible flows. In this paper we are interested in proving the announced result in Haspot (Proceedings of the 14th international conference on hyperbolic problems held in Padova, pp 667-674, 2014) concerning the existence of global weak solution for the quasi-solutions, we also observe that for some choice of initial data (irrotationnal) the quasi solutions verify the porous media, the heat equation or the fast diffusion equations in function of the structure of the viscosity coefficients. In particular it implies that it exists classical quasi-solutions in the sense that they are {C^{∞}} on {(0,T)× {R}N} for any {T > 0}. Finally we show the convergence of the global weak solution of compressible Navier-Stokes equations to the quasi solutions in the case of a vanishing pressure limit process. In particular for highly compressible equations the speed of propagation of the density is quasi finite when the viscosity corresponds to {μ(ρ)=ρ^{α}} with {α > 1}. Furthermore the density is not far from converging asymptotically in time to the Barrenblatt solution of mass the initial density {ρ0}.
Winkler, Michael
2017-02-01
The Neumann initial-boundary value problem for the chemotaxis system {ut=∇ṡ(D(u)∇u)-∇ṡ(S(u)∇v),vt=Δv-v+u,(⋆) is considered in a bounded domain Ω \\subset {{{R}}n} , n≥slant 1 , with smooth boundary. In compliance with refined modeling approaches, the diffusivity function D therein is allowed to decay considerably fast at large densities, where a particular focus will be on the mathematically delicate case when D(s) decays exponentially as s\\to ∞ . In such situations, namely, straightforward Moser-type recursive arguments for the derivation of {{L}∞} estimates for u from corresponding L p bounds seem to fail. Accordingly, results on global existence, and especially on quantitative upper bounds for solutions, so far mainly concentrate on cases when D decays at most algebraically, and hence are unavailable in the present context. This work develops an alternative approach, at its core based on a Moser-type iteration for the quantity {{\\text{e}}u} , to establish global existence of classical solutions for all reasonably regular initial data, as well as a logarithmic upper estimate for the possible growth of \\parallel u(\\centerdot,t){{\\parallel}{{L∞}(Ω )}} as t\\to ∞ , under the assumptions that with some K 1 > 0, K 2 > 0, {β-}>0 and {β+}\\in ≤ft(-∞,{β-}\\right] we have {{K}1}{{\\text{e}}-{β-}s}}≤slant D(s)≤slant {{K}2}{{\\text{e}}-{{β+}s}} for all s≥slant 0 , and that the size of S relative to D can be estimated according to \\frac{S(s)}{D(s)}≤slant {{K}3}{{\\text{e}}γ s} for all s≥slant 0 with some K 3 > 0 and γ \\in ≤ft[\\frac{{{β+}-{β-}}{2},\\frac{{β+}}{2}\\right) . Making use of the fact that this allows for certain superalgebraic growth of \\frac{S}{D} , as a particular consequence of this and known results on nonexistence of global bounded solutions we shall see that in the prototypical case when D(s)={{\\text{e}}-β s} and S(s)=s{{\\text{e}}-α s} for all s≥slant 0 and some
Duan, Ran; Guo, Ai; Zhu, Changjiang
2017-04-01
We obtain existence and uniqueness of global strong solution to one-dimensional compressible Navier-Stokes equations for ideal polytropic gas flow, with density dependent viscosity and temperature dependent heat conductivity under stress-free and thermally insulated boundary conditions. Here we assume viscosity coefficient μ (ρ) = 1 +ρα and heat conductivity coefficient κ (θ) =θβ for all α ∈ [ 0 , ∞) and β ∈ (0 , + ∞).
Spatially-explicit models of global tree density
Glick, Henry B.; Bettigole, Charlie; Maynard, Daniel S.; Covey, Kristofer R.; Smith, Jeffrey R.; Crowther, Thomas W.
2016-01-01
Remote sensing and geographic analysis of woody vegetation provide means of evaluating the distribution of natural resources, patterns of biodiversity and ecosystem structure, and socio-economic drivers of resource utilization. While these methods bring geographic datasets with global coverage into
Zhensheng GAO; Zhong TAN; Guochun WU
2014-01-01
In this paper, we are concerned with the global existence and convergence rates of the smooth solutions for the compressible magnetohydrodynamic equations without heat conductivity, which is a hyperbolic-parabolic system. The global solutions are obtained by combining the local existence and a priori estimates if H3-norm of the initial perturbation around a constant states is small enough and its L1-norm is bounded. A priori decay-in-time estimates on the pressure, velocity and magnetic field are used to get the uniform bound of entropy. Moreover, the optimal convergence rates are also obtained.
Laura C Pollitt
2015-07-01
Full Text Available Very little is known about how vector-borne pathogens interact within their vector and how this impacts transmission. Here we show that mosquitoes can accumulate mixed strain malaria infections after feeding on multiple hosts. We found that parasites have a greater chance of establishing and reach higher densities if another strain is already present in a mosquito. Mixed infections contained more parasites but these larger populations did not have a detectable impact on vector survival. Together these results suggest that mosquitoes taking multiple infective bites may disproportionally contribute to malaria transmission. This will increase rates of mixed infections in vertebrate hosts, with implications for the evolution of parasite virulence and the spread of drug-resistant strains. Moreover, control measures that reduce parasite prevalence in vertebrate hosts will reduce the likelihood of mosquitoes taking multiple infective feeds, and thus disproportionally reduce transmission. More generally, our study shows that the types of strain interactions detected in vertebrate hosts cannot necessarily be extrapolated to vectors.
Global existence conditions for a non-local problem arising in statistical mechanics
Duijn, C.J. van; Guerra, I.A.; Peletier, M.A.
2001-01-01
We consider the evolution of the density and temperature of athree-dimensional cloud of self-interacting particles. This phenomenon ismodelled by a parabolic equation for the density distributioncombining temperature-dependent diffusion and convection drivenby the gradient of the gravitational pote
Barrett, John W.; Süli, Endre
2016-07-01
We prove the existence of global-in-time weak solutions to a general class of models that arise from the kinetic theory of dilute solutions of nonhomogeneous polymeric liquids, where the polymer molecules are idealized as bead-spring chains with finitely extensible nonlinear elastic (FENE) type spring potentials. The class of models under consideration involves the unsteady, compressible, isentropic, isothermal Navier-Stokes system in a bounded domain Ω in Rd, d = 2, for the density ρ, the velocity u ˜ and the pressure p of the fluid, with an equation of state of the form p (ρ) =cpργ, where cp is a positive constant and γ > 1. The right-hand side of the Navier-Stokes momentum equation includes an elastic extra-stress tensor, which is the classical Kramers expression. The elastic extra-stress tensor stems from the random movement of the polymer chains and is defined through the associated probability density function that satisfies a Fokker-Planck-type parabolic equation, a crucial feature of which is the presence of a centre-of-mass diffusion term. This extends the result in our paper J.W. Barrett and E. Süli (2016) [9], which established the existence of global-in-time weak solutions to the system for d ∈ { 2 , 3 } and γ >3/2, but the elastic extra-stress tensor required there the addition of a quadratic interaction term to the classical Kramers expression to complete the compactness argument on which the proof was based. We show here that in the case of d = 2 and γ > 1 the existence of global-in-time weak solutions can be proved in the absence of the quadratic interaction term. Our results require no structural assumptions on the drag term in the Fokker-Planck equation; in particular, the drag term need not be corotational. With a nonnegative initial density ρ0 ∈L∞ (Ω) for the continuity equation; a square-integrable initial velocity datum u˜0 for the Navier-Stokes momentum equation; and a nonnegative initial probability density function ψ0
秦玉明; 李海燕
2014-01-01
This article is devoted to the study of global existence and exponential stability of solutions to an initial-boundary value problem of the quasilinear thermo-diffusion equations with second sound by means of multiplicative techniques and energy method provided that the initial data are close to the equilibrium and the relaxation kernel is strongly positive definite and decays exponentially.
无
2008-01-01
By using Gaines and Mawhin's continuation theorem of coincidence degree theory and constructing Lyapunov functionals,a set of easily verifiable sufficient conditions are derived for the existence and global attractivity of a positive periodic solution to a predator-prey system with delays and impulses.
Global Existence of Classical Solutions to a Three-Species Predator-Prey Model with Two Prey-Taxes
Chenglin Li
2012-01-01
Full Text Available We are concerned with three-species predator-prey model including two prey-taxes and Holling type II functional response under no flux boundary condition. By applying the contraction mapping principle, the parabolic Schauder estimates, and parabolic Lp estimates, we prove that there exists a unique global classical solution of this system.
Qin, Yuming; Zhang, Jianlin
2016-12-01
In this paper, we establish the global existence, uniqueness and asymptotic behavior of cylindrically symmetric solutions for the 3D infrarelativistic model with radiation in H^i× (H^i)^3× H^i× H^{i+1}(i=1,2,4) . The key point is that the smallness of initial data is not needed.
YANG Ling'e; GUO Boling
2006-01-01
By the uniform a priori estimate of solution about parameters, we prove the existence of global solution and inviscid limit to a generalized Ginzburg-Landau equations in two dimensions. We also prove that the solution to the Ginzburg-Landau equations converges to the weak solution to the derivative nonlinear Schrodinger equations.
Zhijian, Yang
The paper studies the global existence, asymptotic behavior and blowup of solutions to the initial boundary value problem for a class of nonlinear wave equations with dissipative term. It proves that under rather mild conditions on nonlinear terms and initial data the above-mentioned problem admits a global weak solution and the solution decays exponentially to zero as t→+∞, respectively, in the states of large initial data and small initial energy. In particular, in the case of space dimension N=1, the weak solution is regularized to be a unique generalized solution. And if the conditions guaranteeing the global existence of weak solutions are not valid, then under the opposite conditions, the solutions of above-mentioned problem blow up in finite time. And an example is given.
黎勇; 陈丽
2002-01-01
In this paper, we study the asymptotic behavior of global smooth solution to the initial boundary problem for the 1-D energy transport model in semiconductor science. We prove that the smooth solution of the problem converges to a stationary solution exponentially fast as t - ∞ when the initial data is a small perturbation of the stationary solution.
Global Existence of Solutions to the Fowler Equation in a Neighbourhood of Travelling-Waves
Afaf Bouharguane
2011-01-01
Full Text Available We investigate a fractional diffusion/anti-diffusion equation proposed by Andrew C. Fowler to describe the dynamics of sand dunes sheared by a fluid flow. In this paper, we prove the global-in-time well-posedness in the neighbourhood of travelling-waves solutions of the Fowler equation.
Global existence of solutions for semilinear damped wave equation in 2-D exterior domain
Ikehata, Ryo
We consider a mixed problem of a damped wave equation utt-Δ u+ ut=| u| p in the two dimensional exterior domain case. Small global in time solutions can be constructed in the case when the power p on the nonlinear term | u| p satisfies p ∗=2Japon. 55 (2002) 33) plays an effective role.
Global scenarios of urban density and its impacts on building energy use through 2050.
Güneralp, Burak; Zhou, Yuyu; Ürge-Vorsatz, Diana; Gupta, Mukesh; Yu, Sha; Patel, Pralit L; Fragkias, Michail; Li, Xiaoma; Seto, Karen C
2017-01-09
Although the scale of impending urbanization is well-acknowledged, we have a limited understanding of how urban forms will change and what their impact will be on building energy use. Using both top-down and bottom-up approaches and scenarios, we examine building energy use for heating and cooling. Globally, the energy use for heating and cooling by the middle of the century will be between 45 and 59 exajoules per year (corresponding to an increase of 7-40% since 2010). Most of this variability is due to the uncertainty in future urban densities of rapidly growing cities in Asia and particularly China. Dense urban development leads to less urban energy use overall. Waiting to retrofit the existing built environment until markets are ready in about 5 years to widely deploy the most advanced renovation technologies leads to more savings in building energy use. Potential for savings in energy use is greatest in China when coupled with efficiency gains. Advanced efficiency makes the least difference compared with the business-as-usual scenario in South Asia and Sub-Saharan Africa but significantly contributes to energy savings in North America and Europe. Systemic efforts that focus on both urban form, of which urban density is an indicator, and energy-efficient technologies, but that also account for potential co-benefits and trade-offs with human well-being can contribute to both local and global sustainability. Particularly in growing cities in the developing world, such efforts can improve the well-being of billions of urban residents and contribute to mitigating climate change by reducing energy use in urban areas.
Global scenarios of urban density and its impacts on building energy use through 2050
Güneralp, Burak; Zhou, Yuyu; Ürge-Vorsatz, Diana; Gupta, Mukesh; Yu, Sha; Patel, Pralit L.; Fragkias, Michail; Li, Xiaoma; Seto, Karen C.
2017-01-01
Although the scale of impending urbanization is well-acknowledged, we have a limited understanding of how urban forms will change and what their impact will be on building energy use. Using both top-down and bottom-up approaches and scenarios, we examine building energy use for heating and cooling. Globally, the energy use for heating and cooling by the middle of the century will be between 45 and 59 exajoules per year (corresponding to an increase of 7–40% since 2010). Most of this variability is due to the uncertainty in future urban densities of rapidly growing cities in Asia and particularly China. Dense urban development leads to less urban energy use overall. Waiting to retrofit the existing built environment until markets are ready in about 5 years to widely deploy the most advanced renovation technologies leads to more savings in building energy use. Potential for savings in energy use is greatest in China when coupled with efficiency gains. Advanced efficiency makes the least difference compared with the business-as-usual scenario in South Asia and Sub-Saharan Africa but significantly contributes to energy savings in North America and Europe. Systemic efforts that focus on both urban form, of which urban density is an indicator, and energy-efficient technologies, but that also account for potential co-benefits and trade-offs with human well-being can contribute to both local and global sustainability. Particularly in growing cities in the developing world, such efforts can improve the well-being of billions of urban residents and contribute to mitigating climate change by reducing energy use in urban areas. PMID:28069957
Relationships between human population density and burned area at continental and global scales.
Bistinas, Ioannis; Oom, Duarte; Sá, Ana C L; Harrison, Sandy P; Prentice, I Colin; Pereira, José M C
2013-01-01
We explore the large spatial variation in the relationship between population density and burned area, using continental-scale Geographically Weighted Regression (GWR) based on 13 years of satellite-derived burned area maps from the global fire emissions database (GFED) and the human population density from the gridded population of the world (GPW 2005). Significant relationships are observed over 51.5% of the global land area, and the area affected varies from continent to continent: population density has a significant impact on fire over most of Asia and Africa but is important in explaining fire over area in croplands. Overall, the relationship between population density and burned area is non-monotonic: burned area initially increases with population density and then decreases when population density exceeds a threshold. These thresholds vary regionally. Our study contributes to improved understanding of how human activities relate to burned area, and should contribute to a better estimate of atmospheric emissions from biomass burning.
Nitsche, Ludwig C.; Nitsche, Johannes M.; Brenner, Howard
1988-01-01
The sedimentation and diffusion of a nonneutrally buoyant Brownian particle in vertical fluid-filled cylinder of finite length which is instantaneously inverted at regular intervals are investigated analytically. A one-dimensional convective-diffusive equation is derived to describe the temporal and spatial evolution of the probability density; a periodicity condition is formulated; the applicability of Fredholm theory is established; and the parameter-space regions are determined within which the existence and uniqueness of solutions are guaranteed. Numerical results for sample problems are presented graphically and briefly characterized.
Global Existence of Smooth Solutions of Compressible Bipolar Euler-Maxwell Equations
XU Qian-jin; LI Xin; FENG Yue-hong
2013-01-01
The bipolar compressible Euler-Maxwell equations as a fluid dynamic model arising from plasma physics to describe the dynamics of the compressible electrons and ions is investigated.This work is concerned with three-dimensional Euler-Maxwell equations with smooth periodic solutions.With the help of the symmetry operator techniques and energy method,the global smooth solution with small amplitude is constructed around a constant equilibrium solution with asymptotic stability property.
Global existence and boundedness in a higher-dimensional quasilinear chemotaxis system
Wang, Yilong; Xiang, Zhaoyin
2015-12-01
This paper deals with the boundedness of global solutions to the quasilinear Keller-Segel system u_t=nabla\\cdotbig(D(u)nabla u-unabla vbig), &quad xinΩ, t>0, v_t=Δ v-uf(v),&quad xinΩ, t>0, nabla u\\cdot ν=0, nabla v\\cdotν=0,&quad xin partialΩ, t>0 in a bounded domain {Ωsubset Rn(n≥ 3)} with smooth boundary, where D( u) is supposed to satisfy D( u) ≥ D 0 u m-1 with some positive constant D 0. It is proved that when {m>2-n+2/2n}, the system possesses global bounded weak solutions for any sufficiently smooth nonnegative initial data. In particular, we improved the recent result by Wang et al. (Z Angew Math Phys, 2015. doi: 10.1007/s00033-014-0491-9 ) in the sense that we established the global boundedness of weak solutions. We also removed the convexity assumption on the domain used by Wang et al. (Z Angew Math Phys 65:1137-1152, 2014, 2015).
Peters, Glen P; Aamaas, Borgar; T Lund, Marianne; Solli, Christian; Fuglestvedt, Jan S
2011-10-15
The Life Cycle Assessment (LCA) impact category "global warming" compares emissions of long-lived greenhouse gases (LLGHGs) using Global Warming Potential (GWP) with a 100-year time-horizon as specified in the Kyoto Protocol. Two weaknesses of this approach are (1) the exclusion of short-lived climate forcers (SLCFs) and biophysical factors despite their established importance, and (2) the use of a particular emission metric (GWP) with a choice of specific time-horizons (20, 100, and 500 years). The GWP and the three time-horizons were based on an illustrative example with value judgments and vague interpretations. Here we illustrate, using LCA data of the transportation sector, the importance of SLCFs relative to LLGHGs, different emission metrics, and different treatments of time. We find that both the inclusion of SLCFs and the choice of emission metric can alter results and thereby change mitigation priorities. The explicit inclusion of time, both for emissions and impacts, can remove value-laden assumptions and provide additional information for impact assessments. We believe that our results show that a debate is needed in the LCA community on the impact category "global warming" covering which emissions to include, the emission metric(s) to use, and the treatment of time.
Global and local threats to coral reef functioning and existence: review and predictions
Wilkinson, C.R. [Australian Institute of Marine Sciences, Townsville, Qld. (Australia)
1999-07-01
Factors causing global degradation of coral reefs are examined briefly as a basis for predicting the likely consequences of increases in these factors. The earlier consensus was that widespread but localized damage from natural factors such as storms, and direct anthropogenic effects such as increased sedimentation, pollution and exploitation, posed the largest immediate threat to coral reefs. Now truly global factors associated with accelerating Global Climate Change are either damaging coral reefs or have the potential to inflict greater damage in the immediate future e.g. increases in coral bleaching and mortality, and reduction in coral calcification due to changes in sea-water chemistry with increasing carbon dioxide concentrations. Rises in sea level will probably disrupt human communities and their cultures by making coral cays uninhabitable, whereas coral reefs will sustain minimal damage from the rise in sea level. The short-term (decades) prognosis is that major reductions are almost certain in the extent and biodiversity of coral reefs, and severe disruptions to cultures and economies dependent on reef resources will occur. The long-term (centuries to millennia) prognosis is more encouraging because coral reefs have remarkable resilience to severe disruption and will probably show this resilience in the future when climate changes either stabilize or reverse.
The Crisis of the Existing Global Paradigm of Governance and Political Economy
Winston P. Nagan
2014-05-01
Full Text Available This article seeks to underline the central challenges to world order that are outcomes of our current system of global, social, power and constitutional processes. The article outlines these major problems which it is suggested represent a crisis for the future trajectory of human survival and well-being. The paper then uses the problem of the emergence of transnational criminal activity in order to underline the limits of the current global paradigm of governance. In effect, in the criminal law context the jurisdiction of sovereign states to attack the problem of transnational crime is hedged with severe limitations. The most important of these limitations is the fact that the jurisdiction over crimes by sovereigns is limited by the territorial character of the definition of sovereignty. Thus a sovereign has a limited capacity to control and police criminal activity whose main locus of operation is generated outside of the territorial reach of the sovereign state. This essentially means that the element of global governance generates a juridical vacuum which permits organized crime to flourish outside of the boundaries of the state but at the same time, having the capacity to penetrate and corrupt the social, political and juridical processes of the sovereign state. The article explores the effort of the UN to provide some form of response to this crisis in the form of an international agreement.
A Key Challenge in Global HRM: Adding New Insights to Existing Expatriate Spouse Adjustment Models
Gupta, Ritu; Banerjee, Pratyush; Gaur, Jighyasu
2012-01-01
This study is an attempt to strengthen the existing knowledge about factors affecting the adjustment process of the trailing expatriate spouse and the subsequent impact of any maladjustment or expatriate failure. We conducted a qualitative enquiry using grounded theory methodology with 26 Indian spouses who had to deal with their partner's…
Global Existence for a Parabolic-hyperbolic Free Boundary Problem Modelling Tumor Growth
Shang-bin Cui; Xue-mei Wei
2005-01-01
In this paper we study a free boundary problem modelling tumor growth, proposed by A. Friedman in 2004. This free boundary problem involves a nonlinear second-order parabolic equation describing the diffusion of nutrient in the tumor, and three nonlinear first-order hyperbolic equations describing the evolution of proliferative cells, quiescent cells and dead cells, respectively. By applying Lp theory of parabolic equations, the characteristic theory of hyperbolic equations, and the Banach fixed point theorem, we prove that this problem has a unique global classical solution.
Li, Bing; Li, Yongkun; Zhang, Xuemei
2016-01-01
In this paper, by using the existence of the exponential dichotomy of linear dynamic equations on time scales and the theory of calculus on time scales, we study the existence and global exponential stability of periodic solutions for a class of n-dimensional neutral dynamic equations on time scales. We also present an example to illustrate the feasibility of our results. The results of this paper are completely new and complementary to the previously known results even in both the case of differential equations (time scale [Formula: see text]) and the case of difference equations (time scale [Formula: see text]).
Fujie, Kentarou; Senba, Takasi
2016-08-01
This paper deals with positive radially symmetric solutions of the Neumann boundary value problem for the fully parabolic chemotaxis system, {ut=Δu-∇ṡ(u∇χ(v))in Ω×(0,∞),τvt=Δv-v+uin Ω×(0,∞), in a ball Ω \\subset {{{R}}2} with general sensitivity function χ (v) satisfying {χ\\prime}>0 and decaying property {χ\\prime}(s)\\to 0 (s\\to ∞ ), parameter τ \\in ≤ft(0,1\\right] and nonnegative radially symmetric initial data. It is shown that if τ \\in ≤ft(0,1\\right] is sufficiently small, then the problem has a unique classical radially symmetric solution, which exists globally and remains uniformly bounded in time. Especially, this result establishes global existence of solutions in the case χ (v)={χ0}log v for all {χ0}>0 , which has been left as an open problem.
On the global existence and uniqueness of solutions to the nonstationary boundary layer system
ZHANG; Jianwen; ZHAO; Junning
2006-01-01
In this paper, we study the problem of boundary layer for nonstationary flows of viscous incompressible fluids. There are some open problems in the field of boundary layer. The method used here is mainly based on a transformation which reduces the boundary layer system to an initial-boundary value problem for a single quasilinear parabolic equation. We prove the existence of weak solutions to the modified nonstationary boundary layer system. Moreover, the stability and uniqueness of weak solutions are discussed.
Global existence and blow-up of solutions to a parabolic system with nonlocal sources and boundaries
2007-01-01
This paper deals with a semi-linear parabolic system with nonlinear nonlocal sources and nonlocal boundaries.By using super-and sub-solution techniques,we first give the sufficient conditions that the classical solution exists globally and blows up in a finite time respectively,and then give the necessary and sufficient conditions that two components u and v blow up simultaneously.Finally,the uniform blow-up profiles in the interior are presented.
Global existence and blow-up of solutions to a parabolic system with nonlocal sources and boundaries
Ling-hua KONG; Ming-xin WANG
2007-01-01
This paper deals with a semi-linear parabolic system with nonlinear nonlocal sources and nonlocal boundaries. By using super- and sub-solution techniques, we first give the sufficient conditions that the classical solution exists globally and blows up in a finite time respectively, and then give the necessary and sufficient conditions that two components u and v blow up simultaneously. Finally, the uniform blow-up profiles in the interior are presented.
Da-qing JIANG; Bao-xue ZHANG; De-hui WANG; Ning-zhong SHI
2007-01-01
This paper discusses a randomized Logistic equation (N)(t) ＝ (r + α(B)(t))N(t)[1 - N(t)/K]with an initial value N(0) ＝ No, and No is a random variable satisfying 0 ＜ No ＜ K. The existence,uniqueness and global attractivity of positive solutions and maximum likelihood estimate (MLE) of the parameters of the equation are studied.
Boudin, Laurent; Grandmont, Céline; Moussa, Ayman
2017-02-01
In this article, we prove the existence of global weak solutions for the incompressible Navier-Stokes-Vlasov system in a three-dimensional time-dependent domain with absorption boundary conditions for the kinetic part. This model arises from the study of respiratory aerosol in the human airways. The proof is based on a regularization and approximation strategy designed for our time-dependent framework.
刘法贵; 孔德兴
2004-01-01
By means of maximum principle for nonlinear hyperbolic systems,the results given by HSIAO Ling and D.Serre was improved for Cauchy problem of compressible adiabatic flow through porous media,and a complete result on the global existence and the blow-up phenomena of classical solutions of these systems.These results show that the dissipation is strong enough to preserve the smoothness of 'small ' solution.
Brüggmann, Dörthe; Richter, Theresa; Klingelhöfer, Doris; Gerber, Alexander; Bundschuh, Matthias; Jaque, Jenny; Groneberg, David A
2016-04-04
Gestational diabetes mellitus (GDM) is associated with substantial morbidity for mothers and their offspring. While clinical and basic research activities on this important disease grow constantly, there is no concise analysis of global architecture of GDM research. Hence, it was the objective of this study to assess the global scientific performance chronologically, geographically and in relation to existing research networks and gender distribution of publishing authors. On the basis of the New Quality and Quantity Indices in Science (NewQIS) platform, scientometric methods were combined with modern visualizing techniques such as density equalizing mapping, and the Web of Science database was used to assess GDM-related entries from 1900 to 2012. Twelve thousand five hundred four GDM-related publications were identified and analyzed. The USA (4295 publications) and the UK (1354 publications) dominated the field concerning research activity, overall citations and country-specific Hirsch-Index, which quantified the impact of a country's published research on the scientific community. Semi-qualitative indices such as country-specific citation rates ranked New Zealand and the UK at top positions. Annual collaborative publications increased steeply between the years 1990 and 2012 (71 to 1157 respectively). Subject category analysis pointed to a minor interest of public health issues in GDM research. Gender analysis in terms of publication authorship revealed a clear dominance of the male gender until 2005; then a trend towards gender equity started and the activity of female scientists grew visibly in many countries. The country-specific gender analysis revealed large differences, i.e. female scientists dominated the scientific output in the USA, whereas the majority of research was published by male authors in countries such as Japan. This study provides the first global sketch of GDM research architecture. While North-American and Western-European countries were
Global existence and exponential decay of the solution for a viscoelastic wave equation with a delay
Dai, Qiuyi; Yang, Zhifeng
2014-10-01
In this paper, we consider initial-boundary value problem of viscoelastic wave equation with a delay term in the interior feedback. Namely, we study the following equation together with initial-boundary conditions of Dirichlet type in Ω × (0, + ∞) and prove that for arbitrary real numbers μ 1 and μ 2, the above-mentioned problem has a unique global solution under suitable assumptions on the kernel g. This improve the results of the previous literature such as Nicaise and Pignotti (SIAM J. Control Optim 45:1561-1585, 2006) and Kirane and Said-Houari (Z. Angew. Math. Phys. 62:1065-1082, 2011) by removing the restriction imposed on μ 1 and μ 2. Furthermore, we also get an exponential decay results for the energy of the concerned problem in the case μ 1 = 0 which solves an open problem proposed by Kirane and Said-Houari (Z. Angew. Math. Phys. 62:1065-1082, 2011).
Cockerill, Peter N.
2016-01-01
Gene expression programs are largely regulated by the tissue-specific expression of lineage-defining transcription factors or by the inducible expression of transcription factors in response to specific stimuli. Here I will review our own work over the last 20 years to show how specific activation signals also lead to the wide-spread re-distribution of pre-existing constitutive transcription factors to sites undergoing chromatin reorganization. I will summarize studies showing that activation of kinase signaling pathways creates open chromatin regions that recruit pre-existing factors which were previously unable to bind to closed chromatin. As models I will draw upon genes activated or primed by receptor signaling in memory T cells, and genes activated by cytokine receptor mutations in acute myeloid leukemia. I also summarize a hit-and-run model of stable epigenetic reprograming in memory T cells, mediated by transient Activator Protein 1 (AP-1) binding, which enables the accelerated activation of inducible enhancers. PMID:28018147
Global Existence and Asymptotic Behavior of Affine Motion of 3D Ideal Fluids Surrounded by Vacuum
Sideris, Thomas C.
2017-07-01
The 3D compressible and incompressible Euler equations with a physical vacuum free boundary condition and affine initial conditions reduce to a globally solvable Hamiltonian system of ordinary differential equations for the deformation gradient in {GL^+(3, R)}. The evolution of the fluid domain is described by a family of ellipsoids whose diameter grows at a rate proportional to time. Upon rescaling to a fixed diameter, the asymptotic limit of the fluid ellipsoid is determined by a positive semi-definite quadratic form of rank r = 1, 2, or 3, corresponding to the asymptotic degeneration of the ellipsoid along 3- r of its principal axes. In the compressible case, the asymptotic limit has rank r = 3, and asymptotic completeness holds, when the adiabatic index {γ} satisfies {4/3 adiabatic index {γ}. In the incompressible case, affine motion reduces to geodesic flow in {SL(3, R)} with the Euclidean metric. For incompressible affine swirling flow, there is a structural instability. Generically, when the vorticity is nonzero, the domains degenerate along only one axis, but the physical vacuum boundary condition fails over a finite time interval. The rescaled fluid domains of irrotational motion can collapse along two axes.
21st Century Global Freshwater Security: Can it Exist and Can Scientists Communicate the Challenges?
Famiglietti, J. S.
2015-12-01
Climate models and decades of satellite data are converging on the unfortunate reality that Earth's water cycle is changing. Paleoclimate indicators remind us that this has always been the case. Freshwater is constantly being exchanged among the atmosphere, ocean, land and ice reservoirs, while on land, patterns of precipitation, evapotranspiration, flooding and drought are shifting. The evolving water cycle of the 21st century will likely be stronger, more variable, and will result in broad swaths of mid-latitude drying, accelerated by the depletion of the world's major groundwater aquifers. A well-defined geography of freshwater 'haves' and 'have-nots' is clearly emerging. What does water sustainability mean under such dynamic climate and hydrologic conditions, in particular when coupled with future projections of population growth? How will water managers cope with these new normals, and how will food and energy production be impacted? The responsibility of communicating this changing global water landscape falls squarely on the shoulders of the academic-research community, yet the challenge of doing so is daunting. In this Special Lecture I will review what our latest research tells us, and I will share my personal experiences with science communication and water diplomacy.
Global existence and decay property of the Timoshenko system in thermoelasticity with second sound
Racke, Reinhard
2012-09-01
Our main focus in the present paper is to study the asymptotic behavior of a nonlinear version of the Timoshenko system in thermoelasticity with second sound. As it has been already proved in Said-Houari and Kasimov (2012) [29], the linear version of this system is of regularity-loss type. It is well known (Hosono and Kawashima (2006) [34], Ide and Kawashima (2008) [27], Kubo and Kawashima (2009) [41]) that the regularity-loss property of the linear problem creates difficulties when dealing with the nonlinear problem. In fact, the dissipative property of the problem becomes very weak in the high frequency region and as a result the classical energy method fails. To overcome this difficulty and following Ide and Kawashima (2008) [27] and Ikehata (2002) [30], we use an energy method with negative weights to create an artificial damping which allows us to control the nonlinearity. We prove that for 0≤k≤[s2]-2 with s<8, the solution of our problem is global in time and decays as
O'Grady, Tina; Wang, Xia; Höner Zu Bentrup, Kerstin; Baddoo, Melody; Concha, Monica; Flemington, Erik K
2016-10-14
Annotation of herpesvirus genomes has traditionally been undertaken through the detection of open reading frames and other genomic motifs, supplemented with sequencing of individual cDNAs. Second generation sequencing and high-density microarray studies have revealed vastly greater herpesvirus transcriptome complexity than is captured by existing annotation. The pervasive nature of overlapping transcription throughout herpesvirus genomes, however, poses substantial problems in resolving transcript structures using these methods alone. We present an approach that combines the unique attributes of Pacific Biosciences Iso-Seq long-read, Illumina short-read and deepCAGE (Cap Analysis of Gene Expression) sequencing to globally resolve polyadenylated isoform structures in replicating Epstein-Barr virus (EBV). Our method, Transcriptome Resolution through Integration of Multi-platform Data (TRIMD), identifies nearly 300 novel EBV transcripts, quadrupling the size of the annotated viral transcriptome. These findings illustrate an array of mechanisms through which EBV achieves functional diversity in its relatively small, compact genome including programmed alternative splicing (e.g. across the IR1 repeats), alternative promoter usage by LMP2 and other latency-associated transcripts, intergenic splicing at the BZLF2 locus, and antisense transcription and pervasive readthrough transcription throughout the genome.
Covariant energy density functionals: nuclear matter constraints and global ground state properties
Afanasjev, A V
2016-01-01
The correlations between global description of the ground state properties (binding energies, charge radii) and nuclear matter properties of the state-of-the-art covariant energy density functionals have been studied. It was concluded that the strict enforcement of the constraints on the nuclear matter properties (NMP) defined in Ref.\\ \\cite{RMF-nm} will not necessary lead to the functionals with good description of the binding energies and other ground and excited state properties. In addition, it will not substantially reduce the uncertainties in the predictions of the binding energies in neutron-rich systems. It turns out that the functionals, which come close to satisfying these NMP constraints, have some problems in the description of existing data. On the other hand, these problems are either absent or much smaller in the functionals which are carefully fitted to finite nuclei but which violate some NMP constraints. This is a consequence of the fact that the properties of finite nuclei are defined not o...
Nuclear energy density functionals: what we can learn about/from their global performance?
Afanasjev, A V; Ray, D; Ring, P
2015-01-01
A short review of recent results on the global performance of covariant energy density functionals is presented. It is focused on the analysis of the accuracy of the description of physical observables of ground and excited states as well as to related theoretical uncertainties. In addition, a global analysis of pairing properties is presented and the impact of pairing on the position of two-neutron drip line is discussed.
Neutron Densities from a Global Analysis of Medium Energy Proton Nucleus Elastic Scattering
Clark, B C; Kerr, L J
2003-01-01
A new method for extracting neutron densities from intermediate energy elastic proton-nucleus scattering observables uses a global Dirac phenomenological (DP) approach based on the Relativistic Impulse Approximation (RIA). Data sets for Ca40, Ca48 and Pb208 in the energy range from 500 MeV to 1040 MeV are considered. The global fits are successful in reproducing the data and in predicting data sets not included in the analysis. Using this global approach, energy independent neutron densities are obtained. The vector point proton density distribution is determined from the empirical charge density after unfolding the proton form factor. The other densities are parametrized. The RMS neutron radius, R_n and the neutron skin thickness S_n obtained from the global fits using the most conservative errors are given as follows: for Ca40 R_n is (3.325 +/- 0.025) fm and S_n (-0.044 +/- 0.036) fm; for Ca48 R_n is (3.463 +/- 0.042) fm and S_n (0.103 +/- 0.045) fm; and for Pb208 R_n is (5.551 +/- 0.038) and S_n (0.116 +/-...
Zhang, Jianlin
2017-04-01
In this paper, we study a large time behavior of the global spherically or cylindrically symmetric solutions in H 1 for the compressible viscous radiative and reactive gas in multi-dimension with large initial data. Precisely, if the initial data are spherically symmetric or cylindrically symmetric, the smallness of initial data is not needed. The main concern of the present paper is to investigate the exponential stability of a solution toward the stationary solution as time goes to infinity. We obtain the uniform positive lower and upper bounds of the density by using different methods.
Parshad, Rana
2013-01-01
The purpose of this manuscript is to propose a model for the biological control of invasive species, via introduction of phenotypically modified organisms into a target population. We are inspired by the earlier Trojan Y Chromosome model [J.B. Gutierrez, J.L. Teem, J. Theo. Bio., 241(22), 333-341, 2006]. However, in the current work, we remove the assumption of logisticgrowth rate, and do not consider the addition of sex-reversed supermales. Also the constant birth and death coefficients, considered earlier, are replaced by functionally dependent ones. In this case the nonlinearities present serious difficulties since they change sign, and the components of the solution are not a priori bounded, in some Lp-space for p large, to permit theapplication of the well known regularizing effect principle. Thus functional methods to deducethe global existence in time, for the system in question, are not applicable. Our techniques are based on the Lyapunov functional method. We prove global existence of solutions, as well asexistence of a finite dimensional global attractor, that supports states of extinction. Our analytical finding are in accordance with numerical simulations, which we also present. © 2013 International Press.
François Waldner
2015-06-01
Full Text Available Timely and accurate information on the global cropland extent is critical for applications in the fields of food security, agricultural monitoring, water management, land-use change modeling and Earth system modeling. On the one hand, it gives detailed location information on where to analyze satellite image time series to assess crop condition. On the other hand, it isolates the agriculture component to focus food security monitoring on agriculture and to assess the potential impacts of climate change on agricultural lands. The cropland class is often poorly captured in global land cover products due to its dynamic nature and the large variety of agro-systems. The overall objective was to evaluate the current availability of cropland datasets in order to propose a strategic planning and effort distribution for future cropland mapping activities and, therefore, to maximize their impact. Following a very comprehensive identification and collection of national to global land cover maps, a multi-criteria analysis was designed at the country level to identify the priority areas for cropland mapping. As a result, the analysis highlighted priority regions, such as Western Africa, Ethiopia, Madagascar and Southeast Asia, for the remote sensing community to focus its efforts. A Unified Cropland Layer at 250 m for the year 2014 was produced combining the fittest products. It was assessed using global validation datasets and yields an overall accuracy ranging from 82%–94%. Masking cropland areas with a global forest map reduced the commission errors from 46% down to 26%. Compared to the GLC-Share and the International Institute for Applied Systems Analysis-International Food Policy Research Institute (IIASA-IFPRI cropland maps, significant spatial disagreements were found, which might be attributed to discrepancies in the cropland definition. This advocates for a shared definition of cropland, as well as global validation datasets relevant for the
Charve, Frédéric
2011-01-01
In the first part of this paper, we prove the existence of global strong solution for Korteweg system in one dimension. In the second part, motivated by the processes of vanishing capillarity-viscosity limit in order to select the physically relevant solutions for a hyperbolic system, we show that the global strong solution of the Korteweg system converges in the case of a $\\gamma$ law for the pressure ($P(\\rho)=a\\rho^{\\gamma}$, $\\gamma>1$) to entropic solution of the compressible Euler equations. In particular it justifies that the Korteweg system is suitable for selecting the physical solutions in the case where the Euler system is strictly hyperbolic. The problem remains open for a Van der Waals pressure because in this case the system is not strictly hyperbolic and in particular the classical theory of Lax and Glimm (see \\cite{Lax,G}) can not be used.
Imed Bachar
2014-01-01
Full Text Available We are interested in the following fractional boundary value problem: Dαu(t+atuσ=0, t∈(0,∞, limt→0t2-αu(t=0, limt→∞t1-αu(t=0, where 1<α<2, σ∈(-1,1, Dα is the standard Riemann-Liouville fractional derivative, and a is a nonnegative continuous function on (0,∞ satisfying some appropriate assumptions related to Karamata regular variation theory. Using the Schauder fixed point theorem, we prove the existence and the uniqueness of a positive solution. We also give a global behavior of such solution.
Zhenguo Luo
2013-01-01
Full Text Available Suffiicient and realistic conditions are established in this paper for the existence and global attractivity of a positive periodic solution to the neutral multidelay logarithmic population model with impulse by using the theory of abstract continuous theorem of k-set contractive operator and some inequality techniques. The results improve and generalize the known ones in Li 1999, Lu and Ge 2004, Y. Luo and Z. G. Luo 2010, and Wang et al. 2009. As an application, we also give an example to illustrate the feasibility of our main results.
Xiu Hui YANG; Fu Cai LI; Chun Hong XIE
2005-01-01
In this paper, we investigate the positive solutions of strongly coupled nonlinear parabolic systems with nonlinear boundary conditions:({ut-α(u,v)△u=g(u,v),vt-b(u,v)△v=h(u,v),(e)u/(e)(g)=d(u,v),(e)u/(e)(g)=f(u,v),)Under appropriate hypotheses on the functions a, b, g, h, d and f, we obtain that the solutions may exist globally or blow up in finite time by utilizing upper and lower solution techniques.
Wei, Ruiying; Guo, Boling; Li, Yin
2017-09-01
The Cauchy problem for the three-dimensional compressible magneto-micropolar fluid equations is considered. Existence of global-in-time smooth solutions is established under the condition that the initial data are small perturbations of some given constant state. Moreover, we obtain the time decay rates of the higher-order spatial derivatives of the solution by combining the Lp-Lq estimates for the linearized equations and the Fourier splitting method, if the initial perturbation is small in H3-norm and bounded in L1-norm.
Gou, Haide; Li, Baolin
2017-01-01
In this paper, we study local and global existence of mild solution for an impulsive fractional functional integro differential equation with non-compact semi-group in Banach spaces. We establish a general framework to find the mild solutions for impulsive fractional integro-differential equations, which will provide an effective way to deal with such problems. The theorems proved in this paper improve and extend some related conclusions on this topic. Finally, two applications are given to illustrate that our results are valuable.
Plant diversity increases with the strength of negative density dependence at the global scale
Joseph A. LaManna; Scott A. Mangan; Alfonso Alonso; Norman A. Bourg; Warren Y. Brockelman; Sarayudh Bunyavejchewin; Li-Wan Chang; Jyh-Min Chiang; George B. Chuyong; Keith Clay; Richard Condit; Susan Cordell; Stuart J. Davies; Tucker J. Furniss; Christian P. Giardina; I. A. U. Nimal Gunatilleke; C. V. Savitri Gunatilleke; Fangliang He; Robert W. Howe; Stephen P. Hubbell; Chang-Fu Hsieh; Faith M. Inman-Narahari; David Janík; Daniel J. Johnson; David Kenfack; Lisa Korte; Kamil Král; Andrew J. Larson; James A. Lutz; Sean M. McMahon; William J. McShea; Hervé R. Memiaghe; Anuttara Nathalang; Vojtech Novotny; Perry S. Ong; David A. Orwig; Rebecca Ostertag; Geoffrey G. Parker; Richard P. Phillips; Lawren Sack; I-Fang Sun; J. Sebastián Tello; Duncan W. Thomas; Benjamin L. Turner; Dilys M. Vela Díaz; Tomáš Vrška; George D. Weiblen; Amy Wolf; Sandra Yap; Jonathan A. Myers
2017-01-01
Theory predicts that higher biodiversity in the tropics is maintained by specialized interactions among plants and their natural enemies that result in conspecific negative density dependence (CNDD). By using more than 3000 species and nearly 2.4 million trees across 24 forest plots worldwide, we show that global patterns in tree species diversity reflect not only...
Hua CHEN; Gongwei LIU
2013-01-01
In this paper,we consider the nonlinearly damped semi-linear wave equation associated with initial and Dirichlet boundary conditions.We prove the existence of a local weak solution and introduce a family of potential wells and discuss the invariants and vacuum isolating behavior of solutions.Furthermore,we prove the global existence of solutions in both cases which are polynomial and exponential decay in the energy space respectively,and the asymptotic behavior of solutions for the cases of potential well family with 0 ＜ E(0) ＜ d.At last we show that the energy will grow up as an exponential function as time goes to infinity,provided the initial data is large enough or E(0) ＜ 0.
Does a General Temperature-Dependent Q10 Model of Soil Respiration Exist at Biome and Global Scale?
Hua CHEN; Han-Qin TIAN
2005-01-01
Soil respiration (SR) is commonly modeled by a Q10 (an indicator of temperature sensitivity)function in ecosystem models. Q10is usually treated as a constant of 2 in these models, although Q10 value of SR often decreases with increasing temperatures. It remains unclear whether a general temperaturedependent Q10 model of SR exists at biome and global scale. In this paper, we have compiled the long-term Q10 data of 38 SR studies ranging from the Boreal, Temperate, to Tropical/Subtropical biome on four continents.Our analysis indicated that the general temperature-dependent biome Q10 models of SR existed, especially in the Boreal and Temperate biomes. A single-exponential model was better than a simple linear model in fitting the average Q10 values at the biome scale. Average soil temperature is a better predictor of Q10 value than average air temperature in these models, especially in the Boreal biome. Soil temperature alone could explain about 50% of the Q10 variations in both the Boreal and Temperate biome single-exponential Q10 model. Q10 value of SR decreased with increasing soil temperature but at quite different rates among the three biome Q10 models. The k values (Q10 decay rate constants) were 0.09, 0.07, and 0.02/℃ in the Boreal, Temperate, and Tropical/Subtropical biome, respectively, suggesting that Q10 value is the most sensitive to soil temperature change in the Boreal biome, the second in the Temperate biome, and the least sensitive in the Tropical/Subtropical biome. This also indirectly confirms that acclimation of SR in many soil warming experiments probably occurs. The k value in the "global" single-exponential Q10 model which combined both the Boreal and Temperate biome data set was 0.08/℃. However, the global general temperature-dependent Q10model developed using the data sets of the three biomes is not adequate for predicting Q10 values of SR globally.The existence of the general temperature-dependent Q10 models of SR in the Boreal and
IMPROVING GLOBALlAND30 ARTIFICIAL TYPE EXTRACTION ACCURACY IN LOW-DENSITY RESIDENTS
L. Hou
2016-06-01
Full Text Available GlobalLand 30 is the first 30m resolution land cover product in the world. It covers the area within 80°N and 80°S. There are ten classes including artificial cover, water bodies, woodland, lawn, bare land, cultivated land, wetland, sea area, shrub and snow,. The TM imagery from Landsat is the main data source of GlobalLand 30. In the artificial surface type, one of the omission error happened on low-density residents’ part. In TM images, hash distribution is one of the typical characteristics of the low-density residents, and another one is there are a lot of cultivated lands surrounded the low-density residents. Thus made the low-density residents part being blurred with cultivated land. In order to solve this problem, nighttime light remote sensing image is used as a referenced data, and on the basis of NDBI, we add TM6 to calculate the amount of surface thermal radiation index TR-NDBI (Thermal Radiation Normalized Difference Building Index to achieve the purpose of extracting low-density residents. The result shows that using TR-NDBI and the nighttime light remote sensing image are a feasible and effective method for extracting low-density residents’ areas.
Kimura, I.; Kasahara, Y.; Oya, H.
2001-07-01
It has been necessary requirements to determine the global electron density distribution in the plasmasphere with time resolutions, of less than a day. We have provided solutions to this requirement using the wave normal directions, delay time of Omega signals and the in situ electron density observed on-board the Japanese satellite Akebono (Sawada et al., Journal of Geophysical Research 98(11) (1993) 267, Kimura et al., Advance Space Research 15(2) (1995) 103, Advance Space Research 18(6) (1996) 279, Journal of Atmospheric and Solar-Terrestrial Physics 59 (1997) 1569). The present paper is intended to review our earlier studies.
Phenomena of Blowup and Global Existence of the Solution to a Nonlinear Schrödinger Equation
Xiaowei An
2013-01-01
Full Text Available We consider the following Cauchy problem: -iut=Δu-V(xu+f(x,|u|2u+(W(x⋆|u|2u, x∈ℝN,t>0, u(x, 0=u0(x,x∈ℝN, where V(x and W(x are real-valued potentials and V(x≥0 and W(x is even, f(x,|u|2 is measurable in x and continuous in |u|2, and u0(x is a complex-valued function of x. We obtain some sufficient conditions and establish two sharp thresholds for the blowup and global existence of the solution to the problem.
Li, Hongfei; Jiang, Haijun; Hu, Cheng
2016-03-01
In this paper, we investigate a class of memristor-based BAM neural networks with time-varying delays. Under the framework of Filippov solutions, boundedness and ultimate boundedness of solutions of memristor-based BAM neural networks are guaranteed by Chain rule and inequalities technique. Moreover, a new method involving Yoshizawa-like theorem is favorably employed to acquire the existence of periodic solution. By applying the theory of set-valued maps and functional differential inclusions, an available Lyapunov functional and some new testable algebraic criteria are derived for ensuring the uniqueness and global exponential stability of periodic solution of memristor-based BAM neural networks. The obtained results expand and complement some previous work on memristor-based BAM neural networks. Finally, a numerical example is provided to show the applicability and effectiveness of our theoretical results.
Xu, Jiang; Mori, Naofumi; Kawashima, Shuichi
2015-12-01
As a continued work of [18], we are concerned with the Timoshenko system in the case of non-equal wave speeds, which admits the dissipative structure of regularity-loss. Firstly, with the modification of a priori estimates in [18], we construct global solutions to the Timoshenko system pertaining to data in the Besov space with the regularity s = 3 / 2. Owing to the weaker dissipative mechanism, extra higher regularity than that for the global-in-time existence is usually imposed to obtain the optimal decay rates of classical solutions, so it is almost impossible to obtain the optimal decay rates in the critical space. To overcome the outstanding difficulty, we develop a new frequency-localization time-decay inequality, which captures the information related to the integrability at the high-frequency part. Furthermore, by the energy approach in terms of high-frequency and low-frequency decomposition, we show the optimal decay rate for Timoshenko system in critical Besov spaces, which improves previous works greatly.
Takou, E; Takou, Etienne; Noutchegueme, Norbert
2005-01-01
We prove a global in time existence theorem for the initial values problem for the Einstein-Boltzmann system with cosmological constant and arbitrarily large initial data, in the spatially homogeneous case, in a Robertson-Walker space-time.
Wang, Zhe; Chen, Sow-Hsin, E-mail: sowhsin@mit.edu [Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Liu, Kao-Hsiang [Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan (China); Harriger, Leland; Leão, Juscelino B. [National Institute of Standards and Technology Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)
2014-07-07
The average density of D{sub 2}O confined in a nanoporous silica matrix (MCM-41-S) is studied with neutron scattering. We find that below ∼210 K, the pressure-temperature plane of the system can be divided into two regions. The average density of the confined D{sub 2}O in the higher-pressure region is about 16% larger than that in the lower-pressure region. These two regions could represent the so-called “low-density liquid” and “high-density liquid” phases. The dividing line of these two regions, which could represent the associated 1st order liquid-liquid transition line, is also determined.
Wu, Guochun
2017-01-01
In this paper, we investigate the global existence and uniqueness of strong solutions to the initial boundary value problem for the 3D compressible Navier-Stokes equations without heat conductivity in a bounded domain with slip boundary. The global existence and uniqueness of strong solutions are obtained when the initial data is near its equilibrium in H2 (Ω). Furthermore, the exponential convergence rates of the pressure and velocity are also proved by delicate energy methods.
Keating, G. M.; Tolson, R. H.; Bradford, M. S.
2000-05-01
A study was performed of the long-term orbital decay of five Earth satellites with perigee altitudes averaging near 350km. To decouple long-term trend measurements from the effects of solar variability, measurements were evaluated during the years of solar minimum (1976, 1986 and 1996). Atmospheric densities derived from these essentially global measurements showed substantial evidence of a decline averaging 9.8 ± 2.5% in thermospheric density over 20 years pointing toward a long-term cooling of the upper atmosphere. Increases in greenhouse gases induced by human activity are hypothesized to warm the Earth's surface and lower atmosphere, but strongly cool the upper atmosphere. Assuming that the 10% increase in CO2 over these 20 years caused cooling resulting in the 10% decline in density, a doubling of CO2 could cause the thermospheric densities measured near 350km to decrease by a factor of 3. This decrease may shrink the altitude of a constant density surface by 40km before the end of the 21st century.
Lewis, Jesse S.; Farnsworth, Matthew L.; Burdett, Chris L.; Theobald, David M.; Gray, Miranda; Miller, Ryan S.
2017-01-01
Biotic and abiotic factors are increasingly acknowledged to synergistically shape broad-scale species distributions. However, the relative importance of biotic and abiotic factors in predicting species distributions is unclear. In particular, biotic factors, such as predation and vegetation, including those resulting from anthropogenic land-use change, are underrepresented in species distribution modeling, but could improve model predictions. Using generalized linear models and model selection techniques, we used 129 estimates of population density of wild pigs (Sus scrofa) from 5 continents to evaluate the relative importance, magnitude, and direction of biotic and abiotic factors in predicting population density of an invasive large mammal with a global distribution. Incorporating diverse biotic factors, including agriculture, vegetation cover, and large carnivore richness, into species distribution modeling substantially improved model fit and predictions. Abiotic factors, including precipitation and potential evapotranspiration, were also important predictors. The predictive map of population density revealed wide-ranging potential for an invasive large mammal to expand its distribution globally. This information can be used to proactively create conservation/management plans to control future invasions. Our study demonstrates that the ongoing paradigm shift, which recognizes that both biotic and abiotic factors shape species distributions across broad scales, can be advanced by incorporating diverse biotic factors. PMID:28276519
MRSA: a density-equalizing mapping analysis of the global research architecture.
Addicks, Johann P; Uibel, Stefanie; Jensen, Anna-Maria; Bundschuh, Matthias; Klingelhoefer, Doris; Groneberg, David A
2014-09-30
Methicillin-resistant Staphylococcus aureus (MRSA) has evolved as an alarming public health thread due to its global spread as hospital and community pathogen. Despite this role, a scientometric analysis has not been performed yet. Therefore, the NewQIS platform was used to conduct a combined density-equalizing mapping and scientometric study. As database, the Web of Science was used, and all entries between 1961 and 2007 were analyzed. In total, 7671 entries were identified. Density equalizing mapping demonstrated a distortion of the world map for the benefit of the USA as leading country with a total output of 2374 publications, followed by the UK (1030) and Japan (862). Citation rate analysis revealed Portugal as leading country with a rate of 35.47 citations per article, followed by New Zealand and Denmark. Country cooperation network analyses showed 743 collaborations with US-UK being most frequent. Network citation analyses indicated the publications that arose from the cooperation of USA and France as well as USA and Japan as the most cited (75.36 and 74.55 citations per collaboration article, respectively). The present study provides the first combined density-equalizing mapping and scientometric analysis of MRSA research. It illustrates the global MRSA research architecture. It can be assumed that this highly relevant topic for public health will achieve even greater dimensions in the future.
Inagaki, Taichi; Ishida, Toyokazu
2016-09-14
Thermal storage, a technology that enables us to control thermal energy, makes it possible to reuse a huge amount of waste heat, and materials with the ability to treat larger thermal energy are in high demand for energy-saving societies. Sugar alcohols are now one promising candidate for phase change materials (PCMs) because of their large thermal storage density. In this study, we computationally design experimentally unknown non-natural sugar alcohols and predict their thermal storage density as a basic step toward the development of new high performance PCMs. The non-natural sugar alcohol molecules are constructed in silico in accordance with the previously suggested molecular design guidelines: linear elongation of a carbon backbone, separated distribution of OH groups, and even numbers of carbon atoms. Their crystal structures are then predicted using the random search method and first-principles calculations. Our molecular simulation results clearly demonstrate that the non-natural sugar alcohols have potential ability to have thermal storage density up to ∼450-500 kJ/kg, which is significantly larger than the maximum thermal storage density of the present known organic PCMs (∼350 kJ/kg). This computational study suggests that, even in the case of H-bonded molecular crystals where the electrostatic energy contributes mainly to thermal storage density, the molecular distortion and van der Waals energies are also important factors to increase thermal storage density. In addition, the comparison between the three eight-carbon non-natural sugar alcohol isomers indicates that the selection of preferable isomers is also essential for large thermal storage density.
Bedrossian, Jacob
2011-01-01
The $L^1$-critical parabolic-elliptic Patlak-Keller-Segel system is a classical model of chemotactic aggregation in micro-organisms well-known to have critical mass phenomena. In this paper we study this critical mass phenomenon in the context of Patlak-Keller-Segel models with spatially varying diffusivity and decay rate of the chemo-attractant. The primary tool for the proof of global existence below the critical mass is the use of pseudo-differential operators to precisely evaluate the leading order quadratic portion of the potential energy (interaction energy). Under the assumption of radial symmetry, blow-up is proved above critical mass using a maximum-principle type argument based on comparing the mass distribution of solutions to a barrier consisting of the unique stationary solutions of the scale-invariant PKS. Although effective where standard Virial methods do not apply, this method seems to be dependent on the assumption of radial symmetry. For technical reasons we work in dimensions three and hig...
Wang, Wei; Ding, Mengyao; Li, Yan
2017-09-01
In this paper we study the global boundedness of solutions to the quasilinear parabolic chemotaxis system: ut = ∇ ṡ (D (u) ∇u - S (u) ∇φ (v)), 0 = Δv - v + u, subject to homogeneous Neumann boundary conditions and the initial data u0 in a bounded and smooth domain Ω ⊂Rn (n ≥ 2), where the diffusivity D (u) is supposed to satisfy D (u) ≥a0(u + 1) - α with a0 > 0 and α ∈ R, while the density-signal governed sensitivity fulfills 0 ≤ S (u) ≤b0(u + 1) β and 0 0 and β , k ∈ R. It is shown that the solution is globally bounded if α + β benefits the global boundedness of solutions due to the weaker chemotactic migration of the signal-dependent sensitivity at high signal concentrations. Moreover, when α + β arrives at the critical value, we establish the global boundedness of solutions for the coefficient χ properly small. It should be emphasized that the smallness of χ under k > 1 is positively related to the total cellular mass ∫Ωu0 dx, which is attributed to the stronger singularity of φ (v) at v = 0 for k > 1 and the fact that v can be estimated from below by a multiple of ∫Ωu0 dx. In addition, distinctive phenomena concerning this model are observed by comparison with the known results.
Global hybrids from the semiclassical atom theory satisfying the local density linear response
Fabiano, E; Cortona, P; Della Sala, F
2015-01-01
We propose global hybrid approximations of the exchange-correlation (XC) energy functional which reproduce well the modified fourth-order gradient expansion of the exchange energy in the semiclassical limit of many-electron neutral atoms and recover the full local density approximation (LDA) linear response. These XC functionals represent the hybrid versions of the APBE functional [Phys. Rev. Lett. 106, 186406, (2011)] yet employing an additional correlation functional which uses the localization concept of the correlation energy density to improve the compatibility with the Hartree-Fock exchange as well as the coupling-constant-resolved XC potential energy. Broad energetical and structural testings, including thermochemistry and geometry, transition metal complexes, non-covalent interactions, gold clusters and small gold-molecule interfaces, as well as an analysis of the hybrid parameters, show that our construction is quite robust. In particular, our testing shows that the resulting hybrid, including 20\\% o...
Where Does the Density Localize? Convergent Behavior for Global Hybrids, Range Separation, and DFT+U
Gani, Terry Z H
2016-01-01
Approximate density functional theory (DFT) suffers from many-electron self- interaction error, otherwise known as delocalization error, that may be diagnosed and then corrected through elimination of the deviation from exact piecewise linear behavior between integer electron numbers. Although paths to correction of energetic delocalization error are well- established, the impact of these corrections on the electron density is less well-studied. Here, we compare the effect on density delocalization of DFT+U, global hybrid tuning, and range- separated hybrid tuning on a diverse test set of 32 transition metal complexes and observe the three methods to have qualitatively equivalent effects on the ground state density. Regardless of valence orbital diffuseness (i.e., from 2p to 5p), ligand electronegativity (i.e., from Al to O), basis set (i.e., plane wave versus localized basis set), metal (i.e., Ti, Fe, Ni) and spin state, or tuning method, we consistently observe substantial charge loss at the metal and gain ...
Novo, Sébastien; Novotný, Antonin
2002-01-01
We consider the steady compressible Navier-Stokes equations in the isentropic regime in a bounded domain of $\\mathbb{R}^{3}$. We show that the renormalized continuity equation holds even if the density is not square integrable. We use this result to prove existence of weak solutions under the sole hypothesis $\\gamma > 3/2$ for the adiabatic constant.
A global scale picture of ionospheric peak electron density changes during geomagnetic storms
Kumar, Vickal V.; Parkinson, Murray L.
2017-04-01
Changes in ionospheric plasma densities can affect society more than ever because of our increasing reliance on communication, surveillance, navigation, and timing technology. Models struggle to predict changes in ionospheric densities at nearly all temporal and spatial scales, especially during geomagnetic storms. Here we combine a 50 year (1965-2015) geomagnetic disturbance storm time (Dst) index with plasma density measurements from a worldwide network of 132 vertical incidence ionosondes to develop a picture of global scale changes in peak plasma density due to geomagnetic storms. Vertical incidence ionosondes provide measurements of the critical frequency of the ionospheric F2 layer (foF2), a direct measure of the peak electron density (NmF2) of the ionosphere. By dissecting the NmF2 perturbations with respect to the local time at storm onset, season, and storm intensity, it is found that (i) the storm-associated depletions (negative storm effects) and enhancements (positive storm effects) are driven by different but related physical mechanisms, and (ii) the depletion mechanism tends to dominate over the enhancement mechanism. The negative storm effects, which are detrimental to HF radio links, are found to start immediately after geomagnetic storm onset in the nightside high-latitude ionosphere. The depletions in the dayside high-latitude ionosphere are delayed by a few hours. The equatorward expansion of negative storm effects is found to be regulated by storm intensity (farthest equatorward and deepest during intense storms), season (largest in summer), and time of day (generally deeper on the nightside). In contrast, positive storm effects typically occur on the dayside midlatitude and low-latitude ionospheric regions when the storms are in the main phase, regardless of the season. Closer to the magnetic equator, moderate density enhancements last up to 40 h during the recovery phase of equinox storms, regardless of the local time. Strikingly, high
Manhart, Angelika; Schmeiser, Christian
2017-01-01
A model for the dynamics of actin filament ends along the leading edge of the lamellipodium is analyzed. It contains accounts of nucleation by branching, of deactivation by capping, and of lateral flow along the leading edge by polymerization. A nonlinearity arises from a Michaelis-Menten type modeling of the branching process. For branching rates large enough compared to capping rates, the existence and stability of nontrivial steady states is investigated. The main result is exponential convergence to nontrivial steady states, proven by investigating the decay of an appropriate Lyapunov functional.
Li, Xiaodi; Song, Shiji
2013-06-01
In this paper, a class of recurrent neural networks with discrete and continuously distributed delays is considered. Sufficient conditions for the existence, uniqueness, and global exponential stability of a periodic solution are obtained by using contraction mapping theorem and stability theory on impulsive functional differential equations. The proposed method, which differs from the existing results in the literature, shows that network models may admit a periodic solution which is globally exponentially stable via proper impulsive control strategies even if it is originally unstable or divergent. Two numerical examples and their computer simulations are offered to show the effectiveness of our new results.
Anh Tuan Trinh
2013-11-01
Full Text Available The existence of positive periodic solutions of a periodic Lotka-Volterra type competition system with delays and feedback controls is studied by applying the continuation theorem of coincidence degree theory. By contracting a suitable Liapunov functional, a set of sufficient conditions for the global asymptotic stability of the positive periodic solution of the system is given. A counterexample is given to show that the result on the existence of positive periodic solution in [4] is incorrect.
Hong-Da Chen
Full Text Available BACKGROUND: Segmental duplication is widely held to be an important mode of genome growth and evolution. Yet how this would affect the global structure of genomes has been little discussed. METHODS/PRINCIPAL FINDINGS: Here, we show that equivalent length, or L(e, a quantity determined by the variance of fluctuating part of the distribution of the k-mer frequencies in a genome, characterizes the latter's global structure. We computed the L(es of 865 complete chromosomes and found that they have nearly universal but (k-dependent values. The differences among the L(e of a chromosome and those of its coding and non-coding parts were found to be slight. CONCLUSIONS: We verified that these non-trivial results are natural consequences of a genome growth model characterized by random segmental duplication and random point mutation, but not of any model whose dominant growth mechanism is not segmental duplication. Our study also indicates that genomes have a nearly universal cumulative "point" mutation density of about 0.73 mutations per site that is compatible with the relatively low mutation rates of (1-5 x 10(-3/site/Mya previously determined by sequence comparison for the human and E. coli genomes.
Brüggmann, Dörthe; Berges, Lea; Klingelhöfer, Doris; Bauer, Jan; Bendels, Michael; Louwen, Frank; Jaque, Jenny; Groneberg, David A
2017-06-01
Polycystic ovary syndrome (PCOS) is the most common cause of female infertility worldwide. Although the related research output is constantly growing, no detailed global map of the scientific architecture has so far been created encompassing quantitative, qualitative, socioeconomic and gender aspects. We used the NewQIS platform to assess all PCOS-related publications indexed between 1900 and 2014 in the Web of Science, and applied density equalizing mapping projections, scientometric techniques and economic benchmarking procedures. A total of 6261 PCOS-specific publications and 703 international research collaborations were found. The USA was identified as the most active country in total and collaborative research activity. In the socioeconomic analysis, the USA was also ranked first (25.49 PCOS-related publications per gross domestic product [GDP]/capita), followed by the UK, Italy and Greece. When research activity was related to population size, Scandinavian countries and Greece were leading the field. For many highly productive countries, gender analysis revealed a high ratio of female scientists working on PCOS with the exception of Japan. In this study, we have created the first picture of global PCOS research, which largely differs from other gynaecologic conditions and indicates that most related research and collaborations originate from high-income countries. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
2007-01-01
In this paper, we consider the Cauchy problem with initial data given on a semi-bounded axis for inhomogeneous quasilinear hyperbolic systems. Under the assumption that the rightmost (resp. leftmost) eigenvalue is weakly linearly degenerate and the inhomogeneous term satisfies the corresponding matching condition, we obtain the global existence and uniqueness of C1 solution with small and decaying initial data.
Global analysis of quadrupole shape invariants based on covariant energy density functionals
Quan, S.; Chen, Q.; Li, Z. P.; Nikšić, T.; Vretenar, D.
2017-05-01
Background: The coexistence of different geometric shapes at low energies presents a universal structure phenomenon that occurs over the entire chart of nuclides. Studies of the shape coexistence are important for understanding the microscopic origin of collectivity and modifications of shell structure in exotic nuclei far from stability. Purpose: The aim of this work is to provide a systematic analysis of characteristic signatures of coexisting nuclear shapes in different mass regions, using a global self-consistent theoretical method based on universal energy density functionals and the quadrupole collective model. Method: The low-energy excitation spectrum and quadrupole shape invariants of the two lowest 0+ states of even-even nuclei are obtained as solutions of a five-dimensional collective Hamiltonian (5DCH) model, with parameters determined by constrained self-consistent mean-field calculations based on the relativistic energy density functional PC-PK1, and a finite-range pairing interaction. Results: The theoretical excitation energies of the states, 21+,41+,02+,22+,23+, as well as the B (E 2 ;01+→21+) values, are in very good agreement with the corresponding experimental values for 621 even-even nuclei. Quadrupole shape invariants have been implemented to investigate shape coexistence, and the distribution of possible shape-coexisting nuclei is consistent with results obtained in recent theoretical studies and available data. Conclusions: The present analysis has shown that, when based on a universal and consistent microscopic framework of nuclear density functionals, shape invariants provide distinct indicators and reliable predictions for the occurrence of low-energy coexisting shapes. This method is particularly useful for studies of shape coexistence in regions far from stability where few data are available.
Shengmao Fu
2010-01-01
Full Text Available We study a cubic predator-prey system with stage structure for the prey. This system is a generalization of the two-species Lotka-Volterra predator-prey model. Firstly, we consider the asymptotical stability of equilibrium points to the system of ordinary differential equations type. Then, the global existence of solutions and the stability of equilibrium points to the system of weakly coupled reaction-diffusion type are discussed. Finally, the existence of nonnegative classical global solutions to the system of strongly coupled reaction-diffusion type is investigated when the space dimension is less than 6, and the global asymptotic stability of unique positive equilibrium point of the system is proved by constructing Lyapunov functions.
Chen, Jilong; Zhao, Juan; Zheng, Yujun
2014-01-01
Whether natural factors could interpret the rise of the Earth's surface temperature is still controversial. Though numerous recent researches have reported apparent correlations between solar activity and the Earth's climate, solar activity has encountered a big problem when describing the rapid global warming after 1970s. Our investigation shows the good positive correlations between the Earth's surface Ultraviolet irradiance (280-400 nm) and the Earth's surface temperature both in temporal and spatial variations by analyzing the global surface Ultraviolet irradiance (280-400 nm) and global surface temperature data from 1980-1999. The rise of CO$_2$ cannot interpret the good positive correlations, and we could even get an opposite result to the good correlations when employing the rise of CO$_2$ to describe the relation between them. Based on the good positive correlations, we suggest a new effect, named "Highly Excited Water Vapor" (HEWV) effect, which can interpret how the Sun influences the Earth's surfac...
Fan, M; Wang, K; Jiang, D
1999-08-01
In this paper, we study the existence and global attractivity of positive periodic solutions of periodic n-species Lotka-Volterra competition systems. By using the method of coincidence degree and Lyapunov functional, a set of easily verifiable sufficient conditions are derived for the existence of at least one strictly positive (componentwise) periodic solution of periodic n-species Lotka-Volterra competition systems with several deviating arguments and the existence of a unique globally asymptotically stable periodic solution with strictly positive components of periodic n-species Lotka-Volterra competition system with several delays. Some new results are obtained. As an application, we also examine some special cases of the system we considered, which have been studied extensively in the literature. Some known results are improved and generalized.
Toward a global description of nuclear charge radii: Exploring the Fayans energy density functional
Reinhard, P.-G.; Nazarewicz, W.
2017-06-01
Background: Binding energies and charge radii are fundamental properties of atomic nuclei. When inspecting their particle-number dependence, both quantities exhibit pronounced odd-even staggering. While the odd-even effect in binding energy can be attributed to nucleonic pairing, the origin of staggering in charge radii is less straightforward to ascertain. Purpose: In this work, we study the odd-even effect in binding energies and charge radii, and systematic behavior of differential radii, to identify the underlying components of the effective nuclear interaction. Method: We apply nuclear density functional theory using a family of Fayans and Skyrme energy density functionals fitted to similar data sets but using different optimization protocols. We inspect various correlations between differential charge radii, odd-even staggering in energies and radii, and nuclear matter properties. The Fayans functional is assumed to be in the local FaNDF0 form. Detailed analysis is carried out for medium-mass and heavy semimagic nuclei with a particular focus on the Ca chain. Results: By making the surface and pairing terms dependent on density gradients, the Fayans functional offers the superb simultaneous description of odd-even staggering effects in energies and charge radii. Conversely, when the data on differential radii are added to the pool of fit observables, the coupling constants determining the strengths of the gradient terms of Fayans functional are increased by orders of magnitude. The Skyrme functional optimized in this work with the generalized Fayans pairing term offers results of similar quality. We quantify these findings by performing correlation analysis based on the statistical linear regression technique. The nuclear matter parameters characterizing Fayans and Skyrme functionals optimized to similar data sets are fairly close. Conclusion: The Fayans paring functional, with its generalized density dependence, significantly improves the description of
Si, Xin; Ye, Xia
2016-10-01
This paper concerns an initial-boundary value problem of the inhomogeneous incompressible MHD equations in a smooth bounded domain. The viscosity and resistivity coefficients are density-dependent. The global well-posedness of strong solutions is established, provided the initial norms of velocity and magnetic field are suitably small in some sense, or the lower bound of the transport coefficients are large enough. More importantly, there is not any smallness condition on the density and its gradient.
Giai Giang Vo
2015-01-01
Full Text Available This paper is devoted to the study of a wave equation with a boundary condition of many-point type. The existence of weak solutions is proved by using the Galerkin method. Also, the uniqueness and the stability of solutions are established.
Global scenarios of urban density and its impacts on building energy use through 2050
Güneralp, Burak; Zhou, Yuyu; Ürge-Vorsatz, Diana; Gupta, Mukesh; Yu, Sha; Patel, Pralit L.; Fragkias, Michail; Li, Xiaoma; Seto, Karen
2017-08-22
Urban areas play a significant role in planetary sustainability. While the scale of impending urbanization is well acknowledged, we have a limited understanding on how urban forms will change and what their impact will be on building energy use. Using both top-down and bottom-up approaches and scenarios, we examine building energy use, specifically, for heating and cooling. We also assess associated cobenefits and trade-offs with human well-being. Globally, the energy use for heating and cooling by midcentury will reach anywhere from about 45 EJ/yr to 59 EJ/yr (respectively, increases of 5% to 40% over the 2010 estimate). Most of this variability is due to the uncertainty in future urban forms of rapidly growing cities in Asia and, particularly, in China. Compact urban development overall leads to less energy use in urban environments. Delaying the retrofit of the existing built environment leads to more savings in building energy use. Potential for savings in the energy use is greatest in China when coupled with efficiency gains. Advanced efficiency makes the least difference compared to the business-as-usual scenario in energy use for heating and cooling in South Asia and Sub-Saharan Africa but significantly contribute to energy savings in North America and Europe. A systemic effort that focuses on both urban form and energy-efficient technologies, but also accounts for potential co-benefits and trade-offs, can contribute to both local and global sustainability. Particularly in mega-urban regions, such efforts can improve local environments for billions of urban residents and contribute to mitigating climate change by reducing energy use in urban areas and associated greenhouse gas emissions.
Caesarean Section--A Density-Equalizing Mapping Study to Depict Its Global Research Architecture.
Brüggmann, Dörthe; Löhlein, Lena-Katharina; Louwen, Frank; Quarcoo, David; Jaque, Jenny; Klingelhöfer, Doris; Groneberg, David A
2015-11-17
Caesarean section (CS) is a common surgical procedure. Although it has been performed in a modern context for about 100 years, there is no concise analysis of the international architecture of caesarean section research output available so far. Therefore, the present study characterizes the global pattern of the related publications by using the NewQIS (New Quality and Quantity Indices in Science) platform, which combines scientometric methods with density equalizing mapping algorithms. The Web of Science was used as a database. 12,608 publications were identified that originated from 131 countries. The leading nations concerning research activity, overall citations and country-specific h-Index were the USA and the United Kingdom. Relation of the research activity to epidemiologic data indicated that Scandinavian countries including Sweden and Finland were leading the field, whereas, in relation to economic data, countries such as Israel and Ireland led. Semi-qualitative indices such as country-specific citation rates ranked Sweden, Norway and Finland in the top positions. International caesarean section research output continues to grow annually in an era where caesarean section rates increased dramatically over the past decades. With regard to increasing employment of scientometric indicators in performance assessment, these findings should provide useful information for those tasked with the improvement of scientific achievements.
Das, G.C.; Ibohanbi-Singh, K. (Dept. of Mathematics, Manipur Univ., Imphal (India))
1991-01-01
Ion-acoustic solitons in a generalized multicomponent plasma are studied through the derivation of Korteweg-de Vries (K-dV) equation. The negative ions and ion-beams play quantitatively various roles on the existence of solitons in the plasma. Especially, the critical density introduced by the negative ions exhibits the existence of a large amplitude soliton in plasmas and due to which a derivation of a modified K-dV (mK-dV) equation is needed. By taking the higher order nonlinearity in the plasma, the transition of the K-dV equation to the mK-dV equation is also shown. Moreover, various models of the plasma due to the non-isothermality are also considered in the discussions. Further study closely related to the stability of the soliton is made and yields the salient features of the solitons. (orig.).
Zhen WANG; Hui ZHANG
2014-01-01
In this work, we obtain the global existence and uniqueness of classical solu-tions to a viscous liquid-gas two-phase model with mass-dependent viscosity and vacuum in one dimension, where the initial vacuum is allowed. We get the upper and lower bounds of gas and liquid masses n and m by the continuity methods which we use to study the compressible Navier-Stokes equations.
Lakhin, V. P.; Sorokina, E. A., E-mail: sorokina.ekaterina@gmail.com, E-mail: vilkiae@gmail.com; Ilgisonis, V. I. [National Research Centre Kurchatov Institute (Russian Federation); Konovaltseva, L. V. [Peoples’ Friendship University of Russia (Russian Federation)
2015-12-15
A set of reduced linear equations for the description of low-frequency perturbations in toroidally rotating plasma in axisymmetric tokamak is derived in the framework of ideal magnetohydrodynamics. The model suitable for the study of global geodesic acoustic modes (GGAMs) is designed. An example of the use of the developed model for derivation of the integral conditions for GGAM existence and of the corresponding dispersion relation is presented. The paper is dedicated to the memory of academician V.D. Shafranov.
2007-01-01
This paper discusses a randomized Logistic equation N（t）=（r+αB（t））N（t）[1-（N（t）/K）] with an initial value N（0）=N0,and N0 is a random variable satisfying 0＜N0＜K.The existence, uniqueness and global attractivity of positive solutions and maximum likelihood estimate（MLE）of the parameters of the equation are studied.
Baxter, J Erik
2016-01-01
We investigate the existence of black hole and soliton solutions to four dimensional, anti-de Sitter (adS), Einstein-Yang-Mills theories with general semisimple connected and simply connected gauge groups, concentrating on the so-called "regular" case. We here generalise results for the asymptotically flat case, and compare our system with similar results from the well-researched adS $\\mathfrak{su}(N)$ system. We find the analysis differs from the asymptotically flat case in some important ways: the biggest difference is that for $\\Lambda<0$, solutions are much less constrained as $r\\rightarrow\\infty$, making it possible to prove the existence of global solutions to the field equations in some neighbourhood of existing trivial solutions, and in the limit of $|\\Lambda|\\rightarrow\\infty$. In particular, we can identify non-trivial solutions where the gauge field functions have no zeroes, which in the $\\mathfrak{su}(N)$ case proved important to stability.
Power spectral density and scaling exponent of high frequency global solar radiation sequences
Calif, Rudy; Schmitt, François G.; Huang, Yongxiang
2013-04-01
invariance: Iq(f) ~ f-?(q) , ?(q) is the scaling exponent. This allows to characterize the scaling behavior of a process: fractal or multifractal with intermittent properties. For q = 2, the Hilbert spectrum is defined. In this work, The data are collected at the University site of Guadeloupe, an island in the West Indies, located at 16°15 N latitude 60°30 W longitude. Our measurements sampled at 1 Hz were performed during one year period. The analyzed data present a power spectral density E(f) displaying a power law of the form E(f) ~ f-β with 1.6 ˜ β ˜ 2.2 for frequencies f ˜ 0.1 Hz, corresponding to time scales T × 10 s. Furthermore, global solar radiation data possesses multifractal properties. For comparison, other multifractal analysis techniques such as structure functions, MDFA, wavelet leaders are also used. This preliminary work set the basis for further investigation dedicated to simulate and forecast a sequence of solar energy fluctuation under different meteorological conditions, in the multifractal framework.
Amandeep, K.; Suneel, K.
2017-09-01
The present theoretical calculations have been performed within the framework of IQMD model to study a particular set of mass symmetric and asymmetric reactions (keeping total mass fixed) over a wide range of incident energies and colliding geometries. It has been observed that global as well as local nuclear stopping is influenced by the mass asymmetry of the reaction strongly. Influence of density-dependent symmetry energy has been observed in local nuclear stopping. Global stopping decreases with the increase in colliding geometry. Effect of colliding geometry on nuclear stopping is more at higher energies.
Rincón, Elizabeth; Pérez, Patricia; Chamorro, Eduardo
2007-11-01
The local reactivity proclivities in a series of simple substituted nitrenes (N-X) and phosphinidenes (P-X) have been explored for the lowest-lying singlet and triplet electronic states within the framework of spin-polarized density functional theory (SP-DFT). Linear correlations have been found between both the global and local philicities for spin polarization and the vertical singlet-triplet energy gaps. The accumulation and depletion of the electron or spin density can be directly related to the electronegativity of the substituent atoms. The local analysis has been achieved on the basis of a recent implementation of condensed-to-site SP-DFT Fukui functions.
Baxter, J. Erik
2016-10-01
We investigate the existence of black hole and soliton solutions to four dimensional, anti-de Sitter (adS), Einstein-Yang-Mills theories with general semisimple connected and simply connected gauge groups, concentrating on the so-called regular case. We here generalise results for the asymptotically flat case, and compare our system with similar results from the well-researched adS {mathfrak {su}}(N) system. We find the analysis differs from the asymptotically flat case in some important ways: the biggest difference is that for Λ global solutions to the field equations in some neighbourhood of existing trivial solutions, and in the limit of |Λ |→ infty . In particular, we can identify non-trivial solutions where the gauge field functions have no zeroes, which in the {mathfrak {su}}(N) case proved important to stability.
Cavaco, A.; Canhoto, P.; Costa, M. J.; Collares-Pereira, M.
2016-05-01
The present work describes the measurement effort for direct normal irradiance (DNI) evaluation in the sunny south of Portugal, with a network of eight radiation measurement stations in several locations (including Évora) providing a good coverage of the region. This new initiative for DNI measurement will still need many years (typically 10 or more) to produce a time series which can claim having long term statistical value. This problem can, however, be temporarily mitigated by measuring DNI at the same time as GHI and DHI, in a place where long term series dating back, already exist for those two. It so happens that a long term series (20 years) of global and diffuse solar irradiation exists for the location Évora. So the expectation is to establish correlations with the goal of attributing at least some long term statistical significance to the short and recent DNI series. The paper describes the setup of the measuring stations and presents the preliminary measurements obtained. It further presents the first correlations of monthly averages between normal beam (DNI), global and diffuse radiation. It then uses these correlations, admittedly without acceptable statistical significance (short series of less than one year of measured data), to exemplify how to get a prediction of long term DNI for Évora. This preliminary obtained value is compared to that predicted by the commercial data from Meteonorm.
Penile density and globally used chemicals in Canadian and Greenland polar bears
Sonne, Christian; Dyck, Markus; Rigét, Frank F
2015-01-01
could be in a range that may lead to disruption of normal reproduction and development. It is therefore likely that EDCs directly affect development and bone density in polar bears. Canadian bears had in general the best health and the North East Greenland subpopulation being at the highest risk...
范玮丽
2008-01-01
This paper mainly talks about the currently hot topic-globalization. Firstly, it brings out the general trend about globalization and how to better understand its implication. Secondly, it largely focuses on how to deal with it properly, especially for international marketers. Then, facing with the overwhelming trend, it is time for us to think about seriously what has globalization brought to us. Last but not least, it summarized the author's personal view about the future of globalization and how should we go.
Tulio Rosembuj
2006-12-01
Full Text Available There is no singular globalization, nor is the result of an individual agent. We could start by saying that global action has different angles and subjects who perform it are different, as well as its objectives. The global is an invisible invasion of materials and immediate effects.
Arinami, Tadao; Ohtsuki, Tsuyuka; Ishiguro, Hiroki; Ujike, Hiroshi; Tanaka, Yuji; Morita, Yukitaka; Mineta, Mari; Takeichi, Masashi; Yamada, Shigeto; Imamura, Akira; Ohara, Koichi; Shibuya, Haruo; Ohara, Kenshiro; Suzuki, Yasuo; Muratake, Tatsuyuki; Kaneko, Naoshi; Someya, Toshiyuki; Inada, Toshiya; Yoshikawa, Takeo; Toyota, Tomoko; Yamada, Kazuo; Kojima, Takuya; Takahashi, Sakae; Osamu, Ohmori; Shinkai, Takahiro; Nakamura, Michiko; Fukuzako, Hiroshi; Hashiguchi, Tomo; Niwa, Shin-ich; Ueno, Takuya; Tachikawa, Hirokazu; Hori, Takafumi; Asada, Takashi; Nanko, Shinichiro; Kunugi, Hiroshi; Hashimoto, Ryota; Ozaki, Norio; Iwata, Nakao; Harano, Mutsuo; Arai, Heii; Ohnuma, Tohru; Kusumi, Ichiro; Koyama, Tsukasa; Yoneda, Hiroshi; Fukumaki, Yasuyuki; Shibata, Hiroki; Kaneko, Sunao; Higuchi, Hisashi; Yasui-Furukori, Norio; Numachi, Yohtaro; Itokawa, Masanari; Okazaki, Yuji
2005-01-01
The Japanese Schizophrenia Sib-Pair Linkage Group (JSSLG) is a multisite collaborative study group that was organized to create a national resource for affected sib pair (ASP) studies of schizophrenia in Japan. We used a high-density single-nucleotide–polymorphism (SNP) genotyping assay, the Illumina BeadArray linkage mapping panel (version 4) comprising 5,861 SNPs, to perform a genomewide linkage analysis of JSSLG samples comprising 236 Japanese families with 268 nonindependent ASPs with schizophrenia. All subjects were Japanese. Among these families, 122 families comprised the same subjects analyzed with short tandem repeat markers. All the probands and their siblings, with the exception of seven siblings with schizoaffective disorder, had schizophrenia. After excluding SNPs with high linkage disequilibrium, we found significant evidence of linkage of schizophrenia to chromosome 1p21.2-1p13.2 (LOD=3.39) and suggestive evidence of linkage to 14q11.2 (LOD=2.87), 14q11.2-q13.2 (LOD=2.33), and 20p12.1-p11.2 (LOD=2.33). Although linkage to these regions has received little attention, these regions are included in or partially overlap the 10 regions reported by Lewis et al. that passed the two aggregate criteria of a meta-analysis. Results of the present study—which, to our knowledge, is the first genomewide analysis of schizophrenia in ASPs of a single Asian ethnicity that is comparable to the analyses done of ASPs of European descent—indicate the existence of schizophrenia susceptibility loci that are common to different ethnic groups but that likely have different ethnicity-specific effects. PMID:16380906
3D Global Coronal Density Structure and Associated Magnetic Field near Solar Maximum
Kramar, Maxim; Lin, Haosheng
2016-01-01
Measurement of the coronal magnetic field is a crucial ingredient in understanding the nature of solar coronal dynamic phenomena at all scales. We employ STEREO/COR1 data obtained near maximum of solar activity in December 2012 (Carrington rotation, CR 2131) to retrieve and analyze the three-dimensional (3D) coronal electron density in the range of heights from $1.5$ to $4\\ \\mathrm{R}_\\odot$ using a tomography method and qualitatively deduce structures of the coronal magnetic field. The 3D electron density analysis is complemented by the 3D STEREO/EUVI emissivity in 195 \\AA \\ band obtained by tomography for the same CR period. We find that the magnetic field configuration during CR 2131 has a tendency to become radially open at heliocentric distances below $\\sim 2.5 \\ \\mathrm{R}_\\odot$. We compared the reconstructed 3D coronal structures over the CR near the solar maximum to the one at deep solar minimum. Results of our 3D density reconstruction will help to constrain solar coronal field models and test the a...
3D Global Coronal Density Structure and Associated Magnetic Field near Solar Maximum
Maxim Kramar
2016-08-01
Full Text Available Measurement of the coronal magnetic field is a crucial ingredient in understanding the nature of solar coronal dynamic phenomena at all scales. We employ STEREO/COR1 data obtained near maximum of solar activity in December 2012 (Carrington rotation, CR 2131 to retrieve and analyze the three-dimensional (3D coronal electron density in the range of heights from $1.5$ to $4 R_odot$ using a tomography method and qualitatively deduce structures of the coronal magnetic field. The 3D electron density analysis is complemented by the 3D STEREO/EUVI emissivity in 195 AA band obtained by tomography for the same CR period. We find that the magnetic field configuration during CR 2131 has a tendency to become radially open at heliocentric distances below $sim 2.5 R_odot$. We compared the reconstructed 3D coronal structures over the CR near the solar maximum to the one at deep solar minimum. Results of our 3D density reconstruction will help to constrain solar coronal field models and test the accuracy of the magnetic field approximations for coronal modeling.
3D Global Coronal Density Structure and Associated Magnetic Field near Solar Maximum
Kramar, Maxim; Airapetian, Vladimir; Lin, Haosheng
2016-08-01
Measurement of the coronal magnetic field is a crucial ingredient in understanding the nature of solar coronal dynamic phenomena at all scales. We employ STEREO/COR1 data obtained near maximum of solar activity in December 2012 (Carrington rotation, CR 2131) to retrieve and analyze the three-dimensional (3D) coronal electron density in the range of heights from 1.5 to 4 R_⊙ using a tomography method and qualitatively deduce structures of the coronal magnetic field. The 3D electron density analysis is complemented by the 3D STEREO/EUVI emissivity in 195 Å band obtained by tomography for the same CR period. We find that the magnetic field configuration during CR 2131 has a tendency to become radially open at heliocentric distances below ˜ 2.5 R_⊙. We compared the reconstructed 3D coronal structures over the CR near the solar maximum to the one at deep solar minimum. Results of our 3D density reconstruction will help to constrain solar coronal field models and test the accuracy of the magnetic field approximations for coronal modeling.
Ramillien, Guillaume; Frappart, Frédéric; Seoane, Lucia
2016-04-01
We propose a new method to produce time series of global maps of surface mass variations by progressive integration of daily geopotential variations measured by orbiting satellites. In the case of the GRACE mission, these geopotential variations can be determined from very accurate inter-satellite K-Band Range Rate (KBRR) measurements of 5-second daily orbits. In particular, the along-track gravity contribution of hydrological mass changes is extracted by removing de-aliasing models for static field, atmosphere, oceans mass variations (including periodical tides), as well as polar movements. Our determination of surface mass sources is composed of two successive dependent Kalman filter stages. The first one consists of reducing the satellite-based potential anomalies by adjusting the longest spatial wavelengths (i.e., low-degree spherical harmonics lower than 2). In the second stage, the residual potential anomalies from the previous stage are used to recover surface mass density changes - in terms of Equivalent-Water Height (EWH) - over a global network of juxtaposed triangular elements. These surface tiles of ~100,000 km x km (or equivalently 330 km by 330 km) are defined to be of equal areas over the terrestrial sphere. However they can be adapted to the local geometry of the surface mass. Our global approach was tested by inverting geopotential data, and successfully applied to estimate time-varying surface mass densities from real GRACE-based residuals. This strategy of combined Kalman filter-type inversions can also be useful for exploring the possibility of improving time and space resolutions for ocean and land studies that would be hopefully brought by future low altitude geodetic missions.
Heftberger, Peter; Heberle, Frederick A; Pan, Jianjun; Rappolt, Michael; Amenitsch, Heinz; Kucerka, Norbert; Katsaras, John; Pabst, Georg
2013-01-01
We adapted the highly successful scattering density pro?le (SDP) model, which is used to jointly analyze small angle x-ray and neutron scattering data from unilamellar vesicles, for use with data from fully hydrated, liquid crystalline multilamellar vesicles (MLVs). By using a genetic algorithm, this new method is capable of providing high resolution structural information, as well as determining bilayer elastic bending fluctuations from standalone x-ray data. Important structural parameters, such as bilayer thickness and area per lipid were determined for a series of saturated and unsaturated lipids, as well as binary mixtures with cholesterol. Results are in good agreement with previously reported SDP data, which used both neutron and x-ray data. The addition of deuterated and non-deuterated MLV neutron data to the analysis improved lipid backbone information, but did not improve, within experimental uncertainties, the structural information regarding bilayer thickness and area per lipid.
Barrera-Ballesteros, Jorge K; Zhu, Guangtun B; Zakamska, Nadia L; Sánchez, Sebastian F; Law, David; Wake, David; Green, Jenny E; Bizyaev, Dmitry; Oravetz, Daniel; Simmons, Audrey; Malanushenko, Elena; Pan, Kaike; Lopes, Alexandre Roman; Lane, Richard R
2016-01-01
We present the stellar surface mass density {\\it vs.} gas metallicity ($\\Sigma_*-Z$) relation for more than 500,000 spatially-resolved star-forming resolution elements (spaxels) from a sample of 653 disk galaxies included in the SDSS IV MaNGA survey. We find a tight relation between these local properties, with higher metallicities as the surface density increases. This relation extends over three orders of magnitude in the surface mass density and a factor of four in metallicity. We show that this local relationship can simultaneously reproduce two well-known properties of disk galaxies: their global mass-metallicity relationship {\\it and} their radial metallicity gradients. We also find that the $\\Sigma_* - Z$ relation is largely independent of the galaxy's total stellar mass and specific star-formation rate (sSFR), except at low stellar mass and high sSFR. These results suggest that in the present-day universe local properties play a key role in determining the gas-phase metallicity in typical disk galaxie...
Cuoco, A; Haugbølle, T; Kachelrieß, M; Serpico, P D
2009-01-01
We perform an autocorrelation study of the Auger data with the aim to constrain the number density ns of ultrahigh energy cosmic ray (UHECR) sources, estimating at the same time the effect on ns of the systematic energy scale uncertainty and of the distribution of UHECR. The use of global analysis has the advantage that no biases are introduced, either in ns or in the related error bar, by the a priori choice of a single angular scale. The case of continuous, uniformly distributed sources is nominally disfavored at 99% CL and the fit improves if the sources follow the large-scale structure of matter in the universe. The best-fit values obtained for the number density of proton sources are within a factor ~2 around ns 1 × 10–4Mpc–3 and depend mainly on the Auger energy calibration scale, with lower densities being preferred if the current scale is correct. The data show no significant small-scale clustering on scales smaller than a few degrees. This might be interpreted as a signature of magnetic smearing...
Barrera-Ballesteros, Jorge K.; Heckman, Timothy M.; Zhu, Guangtun B.; Zakamska, Nadia L.; Sánchez, Sebastian F.; Law, David; Wake, David; Green, Jenny E.; Bizyaev, Dmitry; Oravetz, Daniel; Simmons, Audrey; Malanushenko, Elena; Pan, Kaike; Roman Lopes, Alexandre; Lane, Richard R.
2016-12-01
We present the stellar surface mass density versus gas metallicity (Σ*-Z) relation for more than 500 000 spatially resolved star-forming resolution elements (spaxels) from a sample of 653 disc galaxies included in the SDSS IV MaNGA survey. We find a tight relation between these local properties, with higher metallicities as the surface density increases. This relation extends over three orders of magnitude in the surface mass density and a factor of 4 in metallicity. We show that this local relationship can simultaneously reproduce two well-known properties of disc galaxies: their global mass-metallicity relationship and their radial metallicity gradients. We also find that the Σ*-Z relation is largely independent of the galaxy's total stellar mass and specific star formation rate (sSFR), except at low stellar mass and high sSFR. These results suggest that in the present-day universe local properties play a key role in determining the gas-phase metallicity in typical disc galaxies.
Pyon, Sunseng, E-mail: pyon@ap.t.u-tokyo.ac.jp; Mine, Akinori; Suwa, Takahiro; Tamegai, Tsuyoshi
2016-11-15
Highlights: • (Ba,K)Fe{sub 2}As{sub 2} superconducting pressed tapes are fabricated. • We found an intriguing anisotropy in J{sub c} determined by magnetic measurements, which is related to microcrack structures affecting the local J{sub c}. • Microcrack structures are directly observed by magneto-optical imaging technique. - Abstract: We demonstrate the fabrication of (Ba,K)Fe{sub 2}As{sub 2} superconducting pressed tapes through a powder-in-tube method using uniaxial cold pressing technique, and evaluate global and local J{sub c} by several physical measurements. We found an intriguing anisotropy in J{sub c} determined by magnetic measurements, which is related to microcrack structures affecting the local J{sub c}. The maximum J{sub c} estimated from magnetization measurements has reached ∼1.9 × 10{sup 5} A/cm{sup 2} under self-field at 4.2 K. Furthermore, microcrack structures are directly observed by magneto-optical imaging technique.
Collet, P; Collet, P; Xin, J
1994-01-01
We consider the initial value problem for the thermal-diffusive combustion systems of the form: u_{1,t}= Delta_{x}u_1 - u_1 u_2^m, u_{2,t}= d Delta_{x} u_2 + u_1 u_2^m, x in R^{n}, n geq 1, m geq 1, d > 1, with bounded uniformly continuous nonnegative initial data. For such initial data, solutions can be simple traveling fronts or complicated domain walls. Due to the well-known thermal-diffusive instabilities when d, the Lewis number, is sufficiently away from one, front solutions are potentially chaotic. It is known in the literature that solutions are uniformly bounded in time in case d leq 1 by a simple comparison argument. In case d >1, no comparison principle seems to apply. Nevertheless, we prove the existence of global classical solutions and show that the L^{infty} norm of u_2 can not grow faster than O(log log t) for any space dimension. Our main tools are local L^{p} a-priori estimates and time dependent spatially decaying test functions. Our results also hold for the Arrhenius type reactions.
徐龙封
2004-01-01
In this paper the nonnegative classical solutions of a parabolic system with nonlinear boundary conditions are discussed. The existence and uniqueness of a nonnegative classical solution are proved. And some sufficient conditions to ensure the global existence and nonexistence of nonnegative classical solution to this problem are given.
Plum, Maja
Globalization is often referred to as external to education - a state of affair facing the modern curriculum with numerous challenges. In this paper it is examined as internal to curriculum; analysed as a problematization in a Foucaultian sense. That is, as a complex of attentions, worries, ways...... of reasoning, producing curricular variables. The analysis is made through an example of early childhood curriculum in Danish Pre-school, and the way the curricular variable of the pre-school child comes into being through globalization as a problematization, carried forth by the comparative practices of PISA...
Dornburg, V.; Faaij, A.; Verweij, P. [Utrecht University, Utrecht (Netherlands); Banse, M.; Van Diepen, K.; Van Keulen, H.; Langeveld, H.; Meeusen, M.; Van de Ven, G.; Wester, F. [Wageningen UR, Wageningen (Netherlands); Alkemade, R.; Ten Brink, B.; Van den Born, G.J.; Van Oorschot, M.; Ros, J.; Smout, F.; Van Vuuren, D.; Van den Wijngaart, R. [Netherlands Environmental Assessment Agency NMP, Bilthoven (Netherlands); Aiking, H. [Vrije Universiteit, Amsterdam (Netherlands); Londo, M.; Mozaffarian, H.; Smekens, K. [ECN Policy Studies, Petten (Netherlands); Lysen, E. (ed.); Van Egmond, S. (ed.) [Utrecht Centre for Energy research UCE, Utrecht University, Utrecht (Netherlands)
2008-01-15
This supporting document contains the result from the inventory phase of the biomass assessment of global biomass potentials and their links to food, water, biodiversity, energy demand and economy. This study provides a comprehensive assessment of global biomass potential estimates, focusing on the various factors affecting these potentials, such as food supplies, water use, biodiversity, energy demands and agro-economics.
Jorda, L.; Gaskell, R.; Capanna, C.; Hviid, S.; Lamy, P.; Ďurech, J.; Faury, G.; Groussin, O.; Gutiérrez, P.; Jackman, C.; Keihm, S. J.; Keller, H. U.; Knollenberg, J.; Kührt, E.; Marchi, S.; Mottola, S.; Palmer, E.; Schloerb, F. P.; Sierks, H.; Vincent, J.-B.; A'Hearn, M. F.; Barbieri, C.; Rodrigo, R.; Koschny, D.; Rickman, H.; Barucci, M. A.; Bertaux, J. L.; Bertini, I.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; Fornasier, S.; Fulle, M.; Güttler, C.; Ip, W.-H.; Kramm, J. R.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lopez Moreno, J. J.; Marzari, F.; Naletto, G.; Oklay, N.; Thomas, N.; Tubiana, C.; Wenzel, K.-P.
2016-10-01
The Rosetta spacecraft reached Comet 67P/Churyumov-Gerasimenko (hereafter 67P/C-G) in August 2014 at an heliocentric distance of 3.6 a.u. and was then put in orbit around its nucleus to perform detailed observations. Among the collected data are the images acquired by the OSIRIS instrument up to the perihelion passage of the comet in August 2015, which allowed us to map the entire nucleus surface at high-resolution in the visible. Stereophotoclinometry methods have been used to reconstruct a global high-resolution shape model and to monitor its rotational parameters using data collected up to perihelion. The nucleus has a conspicuous bilobate shape with overall dimensions along its principal axes of (4.34 ± 0.02) × (2.60 ± 0.02) × (2.12 ± 0.06) km. The best-fit ellipsoid dimensions of the individual lobes along their principal axes of inertia are found to be 4.10 × 3.52 × 1.63 km and 2.50 × 2.14 × 1.64 km. Their volume amounts to 66% and 27% of the total volume of the nucleus. The two lobes are connected by a "neck" whose volume has been estimated to represent ∼7% of the total volume of the comet. Combining the derived volume of 18.8 ± 0.3 km3 with the mass of 9.982 ± 0.003 × 1012 kg determined by the Rosetta/RSI experiment, we obtained a bulk density of the nucleus of 532 ± 7 kg m-3 . Together with the companion value of 535 ± 35 kg m-3 deduced from the stereophotogrammetry shape model of the nucleus (Preusker et al. [2015] Astron. Astrophys. 583, A33), these constitute the first reliable and most accurate determination of the density of a cometary nucleus to date. The calculated porosity is quite large, ranging approximately from 70% to 75% depending upon the assumed density of the dust grains and the dust-to-ice mass ratio. The nature of the porosity, either micro or macro or both, remains unconstrained. The coordinates of the center of gravity are not compatible with a uniform nucleus density. The direction of the offset between the center of
Lu, K Q; Li, Z P; Yao, J M; Meng, J
2015-01-01
We report the first global study of dynamic correlation energies (DCEs) associated with rotational motion and quadrupole shape vibrational motion in a covariant energy density functional (CEDF) for 575 even-even nuclei with proton numbers ranging from $Z=8$ to $Z=108$ by solving a five-dimensional collective Hamiltonian, the collective parameters of which are determined from triaxial relativistic mean-field plus BCS calculation using the PC-PK1 force. After taking into account these beyond mean-field DCEs, the root-mean-square (rms) deviation with respect to nuclear masses is reduced significantly down to 1.14 MeV, which is smaller than those of other successful CEDFs: NL3* (2.96 MeV), DD-ME2 (2.39 MeV), DD-ME$\\delta$ (2.29 MeV) and DD-PC1 (2.01 MeV). Moreover, the rms deviation for two-nucleon separation energies is reduced by $\\sim34\\%$ in comparison with cranking prescription.
陈勇明; 杨晗
2008-01-01
The initial boundary value problem for the fourth-order wave equation utt+△2u+u=|t|p-1u is considered.The existence and uniqueness of global weak solutions is obtained by using the Galerkin method and the concept of stable set due to Sattinger.
Otabe, E.S., E-mail: otabe@cse.kyutech.ac.j [Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka 820-8502 (Japan); Kiuchi, M.; Kawai, S. [Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka 820-8502 (Japan); Morita, Y.; Ge, J.; Ni, B. [Department of Life, Environment and Material Science, Fukuoka Institute of Technology, 3-30-1 Wajirohigashi, Higashi-ku, Fukuoka 811-0295 (Japan); Gao, Z.; Wang, L.; Qi, Y.; Zhang, X.; Ma, Y. [Key Laboratory of Applied Superconductivity, Institute of Electrical Engineering, Chinese Academy of Sciences, P.O. Box 2703, Beijing 100190 (China)
2009-11-01
The critical current densities of polycrystalline bulk SmFeAsO{sub 1-x}F{sub x} prepared by the powder-in-tube (PIT) method and by a conventional solid-state reaction were investigated using the remnant magnetic moment method and Campbell's method. Two types of shielding current, corresponding to global and local critical current densities J{sub c} were observed using both measurement methods. The global and local J{sub c} were on the order of 10{sup 7} A/m{sup 2} and 10{sup 10} A/m{sup 2} at 5 K, respectively. The local J{sub c} decreased slightly with increasing magnetic field. The global J{sub c} was independent of the preparation method, while the local J{sub c} was larger for samples prepared by PIT than for those prepared by solid-state reaction.
MÉSZÁROS, Ilona
2011-01-01
Full Text Available Using continuous monitoring of stem radius combined with sap flow measurements weassessed the effects of environmental conditions on tree radial growth and water status of two coexistingoak species (Quercus petraea and Quercus cerris at high resolution time in growingseasons of 2008 and 2009. The forest (95–100 yr is situated in a xeric site in the transition zonebetween forested and forest-steppe regions in north-eastern Hungary, Bükk mountains (47o90’N,20o46’E, elevation 320–340 m a.s.l.. Weather conditions in the growing season of 2008 (totalrainfall 354 mm, mean daily temperature 17.0 oC was less extreme than in 2009 (total rainfall299 mm, temperature 17.9 oC. Rainfall strongly determined the course of radial growth incrementin trees. Radial growth of trees was limited in 2009 due to the drought in spring. The maximumradial increment of both species was achieved three weeks earlier (4th week of June than in 2008(4th week of July. We used dendrometer monitoring data for estimation of stem (tree waterdeficit (W by measuring water-related changes in stem radius (Zweifel et al. 2005. Themagnitude of tree water deficit variation (W was always smaller in Q. cerris than in Q. petraea.In contrast, Quercus cerris always exhibited larger daytime averages and maxima of sap flowdensity. In August of 2009 when drought became severe there were larger increases in tree waterdeficit (W (50–55 % in both species compared to July as it could be expected from the extentof decreases in sap flow density (24–28%. Our data suggested that due to the low SWC thetranspiration was supported mainly from the inner water storage of trees during prolonged droughtwhich resulted in high stem water deficit (W.
Ibata, Rodrigo A.; Martin, Nicolas F. [Observatoire astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de lUniversité, F-67000 Strasbourg (France); Lewis, Geraint F. [Institute of Astronomy, School of Physics A28, University of Sydney, NSW 2006 (Australia); McConnachie, Alan W. [NRC Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC, V9E 2E7 (Canada); Irwin, Michael J. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Ferguson, Annette M. N.; Bernard, Edouard J.; Peñarrubia, Jorge [Institute for Astronomy, University of Edinburgh, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Babul, Arif; Navarro, Julio [Department of Physics and Astronomy, University of Victoria, 3800 Finnerty Road, Victoria, British Columbia V8P 5C2 (Canada); Chapman, Scott C. [Department of Physics and Atmospheric Science, Dalhousie University, 6310 Coburg Road, Halifax NS B3H 4R2 (Canada); Collins, Michelle [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Fardal, Mark [University of Massachusetts, Department of Astronomy, LGRT 619-E, 710 North Pleasant Street, Amherst, MA 01003-9305 (United States); Mackey, A. D. [RSAA, The Australian National University, Mount Stromlo Observatory, Cotter Road, Weston Creek ACT 2611 (Australia); Rich, R. Michael [Department of Physics and Astronomy, University of California, Los Angeles, PAB, 430 Portola Plaza, Los Angeles, CA 90095-1547 (United States); Tanvir, Nial [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Widrow, Lawrence, E-mail: rodrigo.ibata@astro.unistra.fr [Department of Physics, Engineering Physics, and Astronomy Queen' s University, Kingston, Ontario K7L 3N6 (Canada)
2014-01-10
We present an analysis of the large-scale structure of the halo of the Andromeda galaxy, based on the Pan-Andromeda Archeological Survey (PAndAS), currently the most complete map of resolved stellar populations in any galactic halo. Despite the presence of copious substructures, the global halo populations follow closely power-law profiles that become steeper with increasing metallicity. We divide the sample into stream-like populations and a smooth halo component (defined as the population that cannot be resolved into spatially distinct substructures with PAndAS). Fitting a three-dimensional halo model reveals that the most metal-poor populations ([Fe/H]<−1.7) are distributed approximately spherically (slightly prolate with ellipticity c/a = 1.09 ± 0.03), with only a relatively small fraction residing in discernible stream-like structures (f {sub stream} = 42%). The sphericity of the ancient smooth component strongly hints that the dark matter halo is also approximately spherical. More metal-rich populations contain higher fractions of stars in streams, with f {sub stream} becoming as high as 86% for [Fe/H]>−0.6. The space density of the smooth metal-poor component has a global power-law slope of γ = –3.08 ± 0.07, and a non-parametric fit shows that the slope remains nearly constant from 30 kpc to ∼300 kpc. The total stellar mass in the halo at distances beyond 2° is ∼1.1 × 10{sup 10} M {sub ☉}, while that of the smooth component is ∼3 × 10{sup 9} M {sub ☉}. Extrapolating into the inner galaxy, the total stellar mass of the smooth halo is plausibly ∼8 × 10{sup 9} M {sub ☉}. We detect a substantial metallicity gradient, which declines from ([Fe/H]) = –0.7 at R = 30 kpc to ([Fe/H]) = –1.5 at R = 150 kpc for the full sample, with the smooth halo being ∼0.2 dex more metal poor than the full sample at each radius. While qualitatively in line with expectations from cosmological simulations, these observations are of great importance as
Truhlik, Vladimir; Triskova, Ludmila; Benson, Robert; Bilitza, Dieter; Chu, Philip; Richards, Phil G.; Wang, Yongli
The upper transition height (Ht) (the altitude of the transition from heavy atomic ions to light ions or in the simplest form the transition from O+ to H+) is an important parameter, representing the boundary between the ionosphere and the plasmasphere. Ht is very sensitive to various geophysical parameters, like solar and magnetic activity and strongly depends on latitude and local time. There were numerous studies of this parameter in past decades. In spite of these efforts, no model satisfactorily represents this parameter so far. Moreover, surprising evidence of very low transition heights during the last prolonged solar minimum, of a level never obtained before, have been reported. We investigate the upper transition height on the global scale. We made progress in processing large data sets of Ht deduced from the Alouette/ISIS topside sounder and from the Formosat-3/COSMIC vertical electron-density profiles Ne(h) using the theoretical Global Plasma Ionosphere Density (GPID) model (Webb and Essex, 2004) and a revised non-linear function describing the scale height vs. altitude (Titheridge, 1976) to fit the vertical density profiles to the observed profiles and to determine the upper transition height. Since both methods require the plasma temperatures and their gradients as input, these are calculated using the IRI2012 model. Both methods are verified using a large amount of electron and ion density profiles simulated by the FLIP theoretical model and their accuracy is discussed. We compare the results from Alouette/ISIS and Formosat-3/COSMIC and present a global distribution of the calculated Ht and its dependence on geophysical parameters. Finally we compare it with Ht calculated using the IRI ion composition model. Titheridge, J.E., 1976. Ion Transition Heights from Topside Electron-Density Profiles. Planetary and Space Science 24 (3), 229-245. Webb, P.A., Essex, E.A., 2004. A dynamic global model of the plasmasphere. Journal of Atmospheric and Solar
2000-01-01
This article considers Cauchy problem for quasilinear hyperbolic systems in diagonal form.A necessary and sufficient condition in guaranteeing that Cauchy problem admits a unique global classical solution on t 0 is obtained,and a sharp estimate of the life span for the classical solution is given.
Shihe Xu
2014-01-01
Full Text Available We study a mathematical model for the growth of necrotic tumors with time delays in proliferation. By transforming this problem into an initial-boundary value problem in fixed domain of a coupled system of a parabolic equation and one integrodifferential equation with time delays, in which all equations involve discontinuous terms, and using the approximation method combined with Schauder fixed point theorem, we prove that this problem has a unique global solution in any time interval [0,T].
Schwämmle, Veit; Aspalter, Claudia-Maria; Sidoli, Simone
2014-01-01
Mass spectrometry (MS) is a powerful analytical method for the identification and quantification of co-existing post-translational modifications in histone proteins. One of the most important challenges in current chromatin biology is to characterize the relationships between co-existing histone...... marks, the order and hierarchy of their deposition, and their distinct biological functions. We developed the database CrossTalkDB to organize observed and reported co-existing histone marks as revealed by MS experiments of histone proteins and their derived peptides. Statistical assessment revealed...... sample-specific patterns for the co-frequency of histone post-translational modifications. We implemented a new method to identify positive and negative interplay between pairs of methylation and acetylation marks in proteins. Many of the detected features were conserved between different cell types...
Kazachenko, Sergey; Bulusu, Satya; Thakkar, Ajit J
2013-06-14
Putative global minima are reported for methanol clusters (CH3OH)n with n ≤ 15. The predictions are based on global optimization of three intermolecular potential energy models followed by local optimization and single-point energy calculations using two variants of dispersion-corrected density functional theory. Recurring structural motifs include folded and/or twisted rings, folded rings with a short branch, and stacked rings. Many of the larger structures are stabilized by weak C-H···O bonds.
Ahmad Faizal Ahmad Fuad
2017-04-01
Full Text Available Long-range visual marine aids to navigation are not required for current marine navigational practices. Therefore, the objective of this study was to develop a minimum luminous range for major lighthouses that are still in existence to sustain the operation of the lighthouses in the future. Two steps were involved in the determination of the minimum luminous range, namely the modification of the existing geographical range formula, and the finding of a strong linear correlation between the light intensity and the luminous range with the lowest gradient possible in a graph. The application of the minimum luminous range would eliminate the loom of light beyond the geographical range of the lighthouse. This approach was applied to seven major lighthouses in Peninsular Malaysia, which resulted in a minimum luminous range of between 12 nm to 14 nm, which was a reduction from the existing range of 18 nm to 25 nm. The validation of the minimum luminous range was performed in two ways; using a Full Mission Ship Simulator (FMSS, and matching the proposed minimum luminous range with the lighting system available. The results of the validation by using the FMSS between the luminous range of 25 nm and 14 nm showed that the light could be sighted and identified at 58.7 nm and 58.6 nm, respectively, which was, therefore, not significant. The validation by matching with the lighting equipment available in the market showed that the eight-tier VLB-44, which has replaced the rotating lighting system in the US since 2008, was highly matched with the proposed minimum luminous range. This further validated the minimum luminous range. The minimum luminous range is sufficient for current navigational uses and may reduce the costs for procuring and maintaining lighting systems, and will be able to sustain the operations of lighthouses in this GNSS age.
Fournais, Søren; Hoffmann-Ostenhof, Maria; Hoffmann-Ostenhof, Thomas
2008-01-01
We review recent results by the authors on the regularity of molecular eigenfunctions ψ and their corresponding one-electron densities ρ, as well as of the spherically averaged one-electron atomic density ρ. Furthermore, we prove an exponentially decreasing lower bound for ρ in the case when the ...
Coffey, Victoria; Sazykin, Stan; Chandler, Michael O.; Hairston, Marc; Minow, Joseph I.; Anderson, Brian
2017-01-01
The magnetic storm that commenced on June 22, 2015 was one of the largest storms in the current solar cycle. During this event, ionospheric F-region density measurements from the Floating Potential Measurement Unit (FPMU) on board the International Space Station (ISS) show dramatic depletions in the post-sunset (nighttime) local time sector at equatorial latitudes starting in the main phase of the storm and persisting on several subsequent orbits into the next day. Putting these low-latitude measurements in context with the global dynamics of the storm, we will present results from simulations and observations in our efforts to better understand the effects of this storm on the different regions of the coupled ionosphere-magnetosphere. The consequences of the magnetospheric penetration electric field and their role in the occurrence of these equatorial spread F observations will be investigated through the results of the SAMI3-RCM numerical model, a coupled ionosphere-magnetosphere model with self-consistent large-scale electrodynamics. Specifically, we will investigate the transient signatures of the interplanetary magnetic field component, Bz, and its role in driving the global convection electric field and ionospheric density redistribution. Lastly, measurements from the AMPERE Birkeland currents, DMSP drift velocities and the particle flux dropouts observed from the Magnetospheric Multiscale Mission (MMS) will be correlated with the FPMU density depletions and each other. Together these observations and simulation results will be assembled to provide each region's context to the global dynamics and time evolution of the storm.
Ohlendorf, D.; Schwarze, B.; Groneberg, D.A.; Schwarzer, M. [Goethe-Universitaet Frankfurt/M, Institut fuer Arbeitsmedizin, Sozialmedizin und Umweltmedizin, Frankfurt/M (Germany)
2015-09-15
Despite the great medical importance, there is still no comprehensive scientometric analysis regarding the results of magnetic resonance imaging (MRI) and the development of the importance for the healthcare system. This paper evaluated and analyzed the entire research publication results on the topic of MRI for the period 1981-2007 based on scientometric methods and parameters. A scientometric analysis (database: ISI Web of Science 1981-2007, search terms MRI and magnetic resonance imaging) was performed. The following parameters were analyzed: number of publications, countries of publication, number of citations, citation rate and collaborations, using various analytical and display techniques, including density equalizing map projections. Most of the 49,122 publications on MRI could be attributed to the USA (32.5 %), which also has the most cooperative collaborations. Within Europe, Germany (10.3 %) is the country with the highest number of publications followed by the UK (9.3 %). The western industrialized nations dominate over the rest of the world in terms of scientific developments of MRI. The thematic focus of the publications lies in the fields of radiology and neuroscience. In addition to the journal Neurology most scientific articles were published in Magnetic Resonance in Medicine and Circulation. The results show that the current trend is continuing and the scientific interest in MRI is continuously increasing. (orig.) [German] Trotz der grossen medizinischen Bedeutung existiert bis heute keine umfassende szientometrische Analyse bzgl. der Forschungsergebnisse zur Magnetresonanztomographie (MRT) und der Entwicklung ihrer Bedeutung fuer das Gesundheitssystem. Im vorliegenden Beitrag soll anhand szientometrischer Methoden und Parameter das gesamte Forschungsaufkommen zum Thema MRT fuer den Zeitraum 1981-2007 evaluiert und analysiert werden. Es wurde eine szientometrische Analyse (Datenbank: ISI-Web of Science, 1981-2007; Suchterm &apos
Minoru Tabata
2015-01-01
Full Text Available Assume that economic activities are conducted in a bounded continuous domain where workers move toward regions that offer higher real wages and away from regions that offer below-average real wages. The density of real wages is calculated by solving the nominal wage equation of the continuous Dixit-Stiglitz-Krugman model in an urban-rural setting. The evolution of the density of workers is described by an unknown function of the replicator equation whose growth rate is equal to the difference between the density of real wages and the average real wage. Hence, the evolution of the densities of workers and real wages is described by the system of the nominal wage equation and the replicator equation. This system of equations is an essentially new kind of system of nonlinear integropartial differential equations in the theory of functional equations. The purpose of this paper is to obtain a sufficient condition for the initial value problem for this system to have a unique global solution.
Langowski, Martin P.; von Savigny, Christian; Burrows, John P.; Fussen, Didier; Dawkins, Erin C. M.; Feng, Wuhu; Plane, John M. C.; Marsh, Daniel R.
2017-08-01
During the last decade, several limb sounding satellites have measured the global sodium (Na) number densities in the mesosphere and lower thermosphere (MLT). Datasets are now available from Global Ozone Monitoring by Occultation of Stars (GOMOS), the SCanning Imaging Absorption spectroMeter for Atmospheric CHartography (SCIAMACHY) (both on Envisat) and the Optical Spectrograph and InfraRed Imager System (OSIRIS) (on Odin). Furthermore, global model simulations of the Na layer in the MLT simulated by the Whole Atmosphere Community Climate Model, including the Na species (WACCM-Na), are available. In this paper, we compare these global datasets.The observed and simulated monthly averages of Na vertical column densities agree reasonably well with each other. They show a clear seasonal cycle with a summer minimum most pronounced at the poles. They also show signs of a semi-annual oscillation in the equatorial region. The vertical column densities vary from 0. 5 × 109 to 7 × 109 cm-2 near the poles and from 3 × 109 to 4 × 109 cm-2 at the Equator. The phase of the seasonal cycle and semi-annual oscillation shows small differences between the Na amounts retrieved from different instruments. The full width at half maximum of the profiles is 10 to 16 km for most latitudes, but significantly smaller in the polar summer. The centroid altitudes of the measured sodium profiles range from 89 to 95 km, whereas the model shows on average 2 to 4 km lower centroid altitudes. This may be explained by the mesopause being 3 km lower in the WACCM simulations than in measurements. Despite this global 2-4 km shift, the model captures well the latitudinal and temporal variations. The variation of the WACCM dataset during the year at different latitudes is similar to the one of the measurements. Furthermore, the differences between the measured profiles with different instruments and therefore different local times (LTs) are also present in the model-simulated profiles. This capturing
Happel, T.; Manz, P.; Ryter, F.; Bernert, M.; Dunne, M.; Hennequin, P.; Hetzenecker, A.; Stroth, U.; Conway, G. D.; Guimarais, L.; Honoré, C.; Viezzer, E.; The ASDEX Upgrade Team
2017-01-01
Properties of the I-mode confinement regime on the ASDEX Upgrade tokamak are summarized. A weak dependence of the power threshold for the L-I transition on the toroidal magnetic field strength is found. During improved confinement, the edge radial electric field well deepens. Stability calculations show that the I-mode pedestal is peeling-ballooning stable. Turbulence investigations reveal strongly intermittent density fluctuations linked to the weakly coherent mode in the confined plasma, which become stronger as the confinement quality increases. Across all investigated structure sizes ({{k}\\bot}≈ 5 -12 cm-1, with {{k}\\bot} the perpendicular wavenumber of turbulent density fluctuations), the intermittent turbulence bursts are observed. Comparison with bolometry data shows that they move poloidally toward the X-point and finally end up in the divertor. This might be indicative that they play a role in inhibiting the density profile growth, such that no pedestal is formed in the edge density profile.
刘启明; 杜艳可
2013-01-01
利用泛函微分方程的度理论,研究一类具有时滞的Cohen-Grossberg神经网络的全局分支的存在性,研究结果为该类神经网络的应用设计提供理论基础.%Based on the degree theory of functional differential equations,global existence of Hopf bifurcation in a class of delayed Cohen-Grossberg neural networks is investigated. The results are theoretical foundation for practical design of the neural networks.
黄文毅; 赖绍永; 张健
2011-01-01
对一类带有阻尼项和非负势能的非线性Klin-Gordon方程,通过引入势井方法研究其Cauchy问题,得到了解爆破和整体存在的最佳条件.%The nonlinear Klein-Gordon equation with damping term and nonnegative potentials is investigated. The potential well argument is used to study the Cauchy problem of the equation. A new existence theorem for the global solutions and the blowup solutions of the problem is established. The relation of the above two phenomena is derived as a sharp condition.
Horwitz, James; Zeng, Wen
2008-10-01
As new methods of describing multiple fluid species and other advances enhance the capability of global magnetospheric models to simulate the dynamics of multiple ion species, they also allow more accurate incorporation of ionospheric plasma outflows as source populations into these large scale models. Here, we shall describe the distilled results of numerous physics-based simulations of ionospheric plasma outflows influenced by auroral driving agents in terms of compact analytic expressions in terms of precipitation electron energy flux levels, characteristic energy levels of the precipitating electrons, the peak spectral wave densities for low-frequency electrostatic waves which transversely heat ionospheric ions, and solar zenith angle. The simulations are conducted with the UT Arlington Dynamic Fluid Kinetic (DyFK) ionospheric plasma transport code. We present these analytic expressions for ionospheric origin O^+ and H^+ densities, temperatures and field-aligned flow velocities at the 3 RE altitude inner boundaries of typical magnetospheric models.
Su, Shin-Yi
Longitudinal/seasonal (l/s) variations of ion density structures at the 600-km low-latitude ionosphere observed by ROCSAT-1 between two similar solar activity years of 2000 and 2002 are examined at four different local-time (LT) regions. The gross feature of l/s density structure is almost identical to each other at the four LT regions examined. A complete reproducibility of density structure can be assumed, including the shape of equatorial ionization anomaly (EIA), for identical solar flux input that also implicitly affect other atmospheric components such as the neutral O/N2 ratio and neutral wind variation. The fact that the solar variability effect is thought as the ultimate driver to shape the global ionospheric structure can be confirmed with the reproduction of ROCSAT observations with the simulation results of the TIEGCM model runs using the observed solar flux inputs for various seasons. However, the EIA crestto-valley ratio or no-valley signature in this background density structure can not be used to infer the post-sunset irregularity occurrence rates because the l/s variation of the magnetic declination effect that determines the post-sunset ionospheric conductivity for the ionospheric electrodynamics can not be readily obtained from this ionospheric background structure.
Cinner, Joshua E; Graham, Nicholas A J; Huchery, Cindy; Macneil, M Aaron
2013-06-01
Coral reef fisheries support the livelihoods of millions of people but have been severely and negatively affected by anthropogenic activities. We conducted a systematic review of published data on the biomass of coral reef fishes to explore how the condition of reef fisheries is related to the density of local human populations, proximity of the reef to markets, and key environmental variables (including broad geomorphologic reef type, reef area, and net productivity). When only population density and environmental covariates were considered, high variability in fisheries conditions at low human population densities resulted in relatively weak explanatory models. The presence or absence of human settlements, habitat type, and distance to fish markets provided a much stronger explanatory model for the condition of reef fisheries. Fish biomass remained relatively low within 14 km of markets, then biomass increased exponentially as distance from reefs to markets increased. Our results suggest the need for an increased science and policy focus on markets as both a key driver of the condition of reef fisheries and a potential source of solutions.
Agbemava, S E; Ring, P
2016-01-01
A systematic investigation of octupole deformed nuclei is presented for even-even systems with $Z\\leq 106$ located between the two-proton and two-neutron drip lines. For this study we use five most up-to-date covariant energy density functionals of different types, with a non-linear meson coupling, with density dependent meson couplings, and with density-dependent zero-range interactions. Pairing correlations are treated within relativistic Hartree-Bogoliubov (RHB) theory based on an effective separable particle-particle interaction of finite range. This allows us to assess theoretical uncertainties within the present covariant models for the prediction of physical observables relevant for octupole deformed nuclei. In addition, a detailed comparison with the predictions of non-relativistic models is performed. A new region of octupole deformation, centered around $Z\\sim 98, N\\sim 196$ is predicted for the first time. In terms of its size in the $(Z,N)$ plane and the impact of octupole deformation on binding e...
曲小趁
2015-01-01
The global existence of classical solutions to a PDE with cross‐diffusion is considered , w hich describe the process of cancer cell invasion of surrounding tissue .T he model reflects the interactions between cancer cell ,enzyme and the tissue .In this mathematical model ,the cancer cell density and the tissue density is strong coupling .To overcome the afore said technical ob‐stacle ,the disadvantage of the haptotaxis term can be balanced by the competition of tissue re‐modeling term in a certain sense .A series of a priori estimates are established based on specific combined estimate ,Lp‐estimate and the Moser iteration method ,and the global existence of so‐lution is proved .%研究一个刻画癌细胞浸润其周围正常组织的带交叉扩散的偏微分方程模型整体解的存在性。该模型着重描述癌细胞、基质降解酶以及正常组织三者之间的相互作用。由于此模型中癌细胞密度和基质密度的空间正则性是“强耦合”的，因此利用基质重组中的竞争项来克服趋触项所带来的分析困难。利用特殊的组合估计、L p‐估计和M o ser迭代技巧建立一系列解的先验估计，从而证明解的整体存在性。
Algarra, Andrés G; Basallote, Manuel G; Castillo, Carmen E; Clares, M Paz; Ferrer, Armando; García-España, Enrique; Llinares, José M; Máñez, M Angeles; Soriano, Conxa
2009-02-02
A ligand (L1) (bis(aminoethyl)[2-(4-quinolylmethyl)aminoethyl]amine) containing a 4-quinolylmethyl group attached to one of the terminal amino groups of tris(2-aminoethyl)amine (tren) has been prepared, and its protonation constants and stability constants for the formation of Cu(2+) complexes have been determined. Kinetic studies on the formation of Cu(2+) complexes in slightly acidic solutions and on the acid-promoted complex decomposition strongly suggest that the Cu(2+)-L1 complex exists in solution as a mixture of two species, one of them showing a trigonal bipyramidal (tbp) coordination environment with an absorption maximum at 890 nm in the electronic spectrum, and the other one being square pyramidal (sp) with a maximum at 660 nm. In acidic solution only a species with tbp geometry is formed, whereas in neutral and basic solutions a mixture of species with tbp and sp geometries is formed. The results of density functional theory (DFT) calculations indicate that these results can be rationalized by invoking the existence of an equilibrium of hydrolysis of the Cu-N bond with the amino group supporting the quinoline ring so that CuL1(2+) would be actually a mixture of tbp [CuL1(H(2)O)](2+) and sp [CuL1(H(2)O)(2)](2+). As there are many Cu(2+)-polyamine complexes with electronic spectra that show two overlapping bands at wavelengths close to those observed for the Cu(2+)-L1 complex, the existence of this kind of equilibrium between species with two different geometries can be quite common in the chemistry of these compounds. A correlation found between the position of the absorption maximum and the tau parameter measuring the distortion from the idealized tbp and sp geometries can be used to estimate the actual geometry in solution of this kind of complex.
Cancro, George J.; Tolson, Robert H.; Keating, Gerald M.
1998-01-01
The success of aerobraking by the Mars Global Surveyor (MGS) spacecraft was partly due to the analysis of MGS accelerometer data. Accelerometer data was used to determine the effect of the atmosphere on each orbit, to characterize the nature of the atmosphere, and to predict the atmosphere for future orbits. To interpret the accelerometer data, a data reduction procedure was developed to produce density estimations utilizing inputs from the spacecraft, the Navigation Team, and pre-mission aerothermodynamic studies. This data reduction procedure was based on the calculation of aerodynamic forces from the accelerometer data by considering acceleration due to gravity gradient, solar pressure, angular motion of the MGS, instrument bias, thruster activity, and a vibration component due to the motion of the damaged solar array. Methods were developed to calculate all of the acceleration components including a 4 degree of freedom dynamics model used to gain a greater understanding of the damaged solar array. The total error inherent to the data reduction procedure was calculated as a function of altitude and density considering contributions from ephemeris errors, errors in force coefficient, and instrument errors due to bias and digitization. Comparing the results from this procedure to the data of other MGS Teams has demonstrated that this procedure can quickly and accurately describe the density and vertical structure of the Martian upper atmosphere.
赵娟; 王银霞
2012-01-01
In this paper we prove that global existence of smooth solutions to Cauchy problem for compressible isentropic Euler equations for Chaplygin gases or Karman-Tsien gases in three space dimensions , provided that the initial data are obtained by adding a small smooth perturbation with compact support to a constant state and the vorticity of the initial velocity vanishes.%研究了三维可压等熵Euler方程Cauchy问题光滑解的整体存在性.如果初值是一个常状态的小扰动并且初速度的旋度等于零,证明了三维可压等熵Euler方程Cauchy问题光滑解的整体存在性.
具非局部源项的抛物系统解的整体存在与爆破%Global Existence and Blow Up for a Nonlocal Parabolic System
凌征球; 冯和英; 庞国萍
2012-01-01
考虑一个具有非局部源项的抛物系统非负解的整体存在与爆破问题,通过使用上下解技术,建立了系统的临界指数,而且,相关的分类是最优与最完全的.%This paper investigates the blow-up and global existence of nonnegative solutions to the parabolic system with nonlocal sourcesu(1)=△u+ || uυ ||p(α),υ(1)=△υ+|| uυ ||qβ,(x,t)∈ Ω×(0,T),subject to null Dirichlet boundary conditions.By using the super- and sub-solution techniques,the critical exponent of the system is determined.Furthermore,the related classifications for the parameters in the model are optimal and complete.
杨帆; 蒋达清
2001-01-01
In this paper, we study the existence and global attractivity of positive periodic solutions of a Logistic growth system with feedback control and deviating arguments. A sufficient condition is derived for the existence of a unique periodic solution with strictly positive components which is globally asymptotically stable by using the method of coincidence degree and Liapunov functional. Some new results are obtained. The known results are improved and generalized.
Incompressible flows with piecewise constant density
Danchin, Raphaël
2012-01-01
We investigate the incompressible Navier-Stokes equations with variable density. The aim is to prove existence and uniqueness results in the case of discontinuous ini- tial density. In dimension n = 2, 3, assuming only that the initial density is bounded and bounded away from zero, and that the initial velocity is smooth enough, we get the local-in-time existence of unique solutions. Uniqueness holds in any dimension and for a wider class of velocity fields. Let us emphasize that all those results are true for piecewise constant densities with arbitrarily large jumps. Global results are established in dimension two if the density is close enough to a positive constant, and in n-dimension if, in addition, the initial velocity is small. The Lagrangian formula- tion for describing the flow plays a key role in the analysis that is proposed in the present paper.
Global Existence and Blow-up for a System of Nonlocal Wave Equations%一个局部波动方程组的解的全局存在性与爆破
邓铿
2005-01-01
我们研究初始值问题(e)u1/(e)t2=(e)2u1/(e)x2+‖u2(·,t)‖p, (e)2u2/(e)t2=(e)2u2/(e)x2+‖u1(·,t)‖q,-∞0,u1(x,0)=f1(x), (e)u1/(e)t(x,0)=g1(x),u2(x,0)=f2(x), (e)u2/(e)t(x,0)=g2(x),- ∞0,u1(x,0)=f1(x), (e)u1/(e)t(x,0)=g1(x),u2(x,0)=f2(x), (e)u2/(e)t(x,0)=g2(x),- ∞
Karamanis, Panaghiotis; Marchal, Remi; Carbonniére, Philippe; Pouchan, Claude
2011-07-28
A global theoretical study of the (hyper)polarizabilities of alkali doped Si(10) is presented and discussed. First, a detailed picture about the low lying isomers of Si(10)Li, Si(10)Na, Si(10)K, Si(10)Li(2), Si(10)Na(2), and Si(10)K(2) has been obtained in a global manner. Then, the microscopic first (hyper)polarizabilities of the most stable configurations have been determined by means of ab initio methods of high predictive capability such as those based on the Møller-Plesset perturbation and coupled cluster theory, paying extra attention to the (hyper)polarizabilities of the open shell mono-doped systems Si(10)Li, Si(10)Na, Si(10)K, and the influence of spin contamination. These results were used to assess the performance of methods of low computational cost based on density functional theory (DFT) in the reliable computation of these properties in order to proceed with an in-depth study of their evolution as a function of the alkali metal, the cluster composition, and the cluster structure. The most interesting outcomes of the performed (hyper)polarizability study indicate that while alkali doping leaves the per atom polarizability practically unaffected, influences dramatically the hyperpolarizabilities of Si(10). The lowest energy structures of the mono-doped clusters are characterized by significantly enhanced hyperpolarizabilities as compared to the analogue neutral or charged bare silicon clusters Si(10) and Si(11), while, certain patterns governed by the type and the number of the doping agents are followed. The observed hyperpolarizability increase is found to be in close connection with specific cluster to alkali metal charge transfer excited states and to the cluster structures. Moreover, an interesting correlation between the anisotropy of the electron density, and the hyperpolarizabilities of these systems has been observed. Finally, it is important to note that the presented method assessment points out that among the various DFT functionals used
Beer, C.; Lucht, W.; Gerten, D.; Thonicke, K.; Schmullius, C.
2007-03-01
The current latitudinal gradient in biomass suggests a climate-driven limitation of biomass in high latitudes. Understanding of the underlying processes, and quantification of their relative importance, is required to assess the potential carbon uptake of the biosphere in response to anticipated warming and related changes in tree growth and forest extent in these regions. We analyze the hydrological effects of thawing and freezing of soil on vegetation carbon density (VCD) in permafrost-dominated regions of Siberia using a process-based biogeochemistry-biogeography model, the Lund-Potsdam-Jena Dynamic Global Vegetation Model (LPJ-DGVM). The analysis is based on spatially explicit simulations of coupled daily thaw depth, site hydrology, vegetation distribution, and carbon fluxes influencing VCD subject to climate, soil texture, and atmospheric CO2 concentration. LPJ represents the observed high spring peak of runoff of large Arctic rivers, and simulates a realistic fire return interval of 100 to 200 years in Siberia. The simulated VCD changeover from taiga to tundra is comparable to inventory-based information. Without the consideration of freeze-thaw processes VCD would be overestimated by a factor of 2 in southern taiga to a factor of 5 in northern forest tundra, mainly because available soil water would be overestimated with major effects on fire occurrence and net primary productivity. This suggests that forest growth in high latitudes is not only limited by temperature, radiation, and nutrient availability but also by the availability of liquid soil water.
Tyagi Suresh C
2005-01-01
Full Text Available Abstract Background The importance of low high-density lipoprotein cholesterol (HDL-C, elevated non HDL-C (as part of the metabolic syndrome, prediabetes, and type 2 diabetes mellitus, and an isolated low HDL-C is rapidly emerging. The antiatherosclerotic roles of reverse cholesterol transport and the pleiotropic antioxidant – anti-inflammatory mechanistic effects of HDL-C are undergoing rapid exponential growth. Case presentation In 1997 a 53-year-old Caucasian male presented with a lipoprotein profile of many years duration with an isolated low HDL-C and uric acid levels in the upper quintile of normal. He developed an acute myocardial infarction involving the right coronary artery and had percutaneous transluminal coronary angioplasty with stenting of this lesion. He also demonstrated a non-critical non-flow limiting lesion of the proximal left anterior descending coronary artery at the time of this evaluation. Following a program of global risk reduction this patient has done well over the past 7 years and remains free of any clinical signs and symptoms of atherosclerosis. His HDL-C and uric acid levels are currently in the normal physiological range. Conclusion Low HDL-C and isolated low HDL-C constitute an important risk factor for atherosclerosis. Therapies that lead to a return to normal physiologic range of HDL-C may result in the delay of atherosclerotic progression.
Advancing Fog Effect on VRML and X3D Using Local Fog Density
Seongah Chin
2004-01-01
In this paper an improved fog effect algorithm in VRML and X3 D is presented with respect to expressing density. The fundamental idea in the approach is to adapt local fog density having influence on Iocal regions with various grades of fog density whereas existing VRML and X3 D only make use of global fog effect. Several filters for making different fog density are presented along with experiments showing the correctness of the proposed method.
Yuzhu You
2006-01-01
This review article commences with a comprehensive historical review of the evolution and application of various density surfaces in atmospheric and oceanic studies.The background provides a basis for the birth of the neutral density idea.Attention is paid to the development of the neutral density surface concept from the nonlinearity of the equation of state of seawater.The definition and properties of neutral density surface are described in detail as developed from the equations of state of seawater and the buoyancy frequency when the squared buoyancy frequency N2 is zero, a neutral state of stability.In order to apply the neutral density surface to intermediate water-mass analysis, this review also describes in detail its practical oceanographic application.The mapping technique is focused for the first time on applying regularly gridded data in this review.It is reviewed how a backbone and ribs framework was designed to flesh out from a reference cast and first mapped the global neutral surfaces in the world's oceans.Several mapped neutral density surfaces are presented as examples for each world ocean.The water-mass property is analyzed in each ocean at mid-depth.The characteristics of neutral density surfaces are compared with those of potential density surfaces.
Existing Steel Railway Bridges Evaluation
Vičan, Josef; Gocál, Jozef; Odrobiňák, Jaroslav; Koteš, Peter
2016-12-01
The article describes general principles and basis of evaluation of existing railway bridges based on the concept of load-carrying capacity determination. Compared to the design of a new bridge, the modified reliability level for existing bridges evaluation should be considered due to implementation of the additional data related to bridge condition and behaviour obtained from regular inspections. Based on those data respecting the bridge remaining lifetime, a modification of partial safety factors for actions and materials could be respected in the bridge evaluation process. A great attention is also paid to the specific problems of determination of load-caring capacity of steel railway bridges in service. Recommendation for global analysis and methodology for existing steel bridge superstructure load-carrying capacity determination are described too.
Requirements for existing buildings
Thomsen, Kirsten Engelund; Wittchen, Kim Bjarne
2012-01-01
This report collects energy performance requirements for existing buildings in European member states by June 2012.......This report collects energy performance requirements for existing buildings in European member states by June 2012....
Requirements for existing buildings
Thomsen, Kirsten Engelund; Wittchen, Kim Bjarne
2012-01-01
This report collects energy performance requirements for existing buildings in European member states by June 2012.......This report collects energy performance requirements for existing buildings in European member states by June 2012....
Tachi, Susumu; Arai, Hirohiko; Maeda, Taro
1989-01-01
Tele-existence is an advanced type of teleoperation system that enables a human operator at the controls to perform remote manipulation tasks dexterously with the feeling that he or she exists in the remote anthropomorphic robot in the remote environment. The concept of a tele-existence is presented, the principle of the tele-existence display method is explained, some of the prototype systems are described, and its space application is discussed.
Hamilton, W. B.; Anderson, D. L.; Foulger, G. R.; Winterer, E. L.
Hypothetical plumes from the deep mantle are widely assumed to provide an abso- lute hotspot reference frame, inaugurate rifting, drive plates, and profoundly influence magmatic and tectonic evolution of oceans and continents. Many papers on local to global tectonics, magmatism, and geochemistry invoke plumes, and assign to the man- tle whatever properties, dynamics, and composition are needed to enable them. The fixed-plume concept arose from the Emperor-Hawaii seamount-and-island province, the 45 Ma inflection in which was assumed to record a 60-degree change in direction by the Pacific plate. Paleomagnetic latitudes and smooth Pacific spreading patterns show that such a change did not occur. Other Pacific chains once assumed to be syn- chronous with, and Euler-parallel to, Hawaii have proved to be neither. Thermal and physical properties of Hawaiian lithosphere falsify plume predictions. Rationales for fixed hotspots elsewhere also have become untenable as databases enlarged. Astheno- sphere is everywhere near solidus temperature, so buoyant melt does not require a local heat source but, rather, needs a thin roof or crack or tensional setting for egress. MORB and ocean-island basalt (OIB) broadly intergrade in composition, but MORB typically is richer in refractory elements and their radiogenic daughters, whereas OIB commonly is richer in fusible elements and their daughters. MORB and OIB contrasts are required by melt behavior and do not indicate unlike source reservoirs. MORB melts rise, with minimal reaction, through hot asthenosphere, whereas OIB melts re- act, and thereby lose substance, by crystallizing refractories and retaining and assim- ilating subordinate fusibles, with thick, cool lithosphere and crust. There is no need for hypotheses involving chaotic plume behavior or thousands of km of lateral flow of plume material, nor for postulates of SprimitiveT lower mantle contrary to cos- & cedil;mological and thermodynamic considerations. Plume
Olivier JGJ; LAE
1995-01-01
An estimate was made of present global emissions from air traffic using statistical information on fuel consumption, aircraft types and applying emission factors for various compounds. To generate scenarios for future emissions from air traffic, assumptions were used regarding the development of the
Akers, David
1990-10-01
A status report is presented on the existence of quarks carrying the Dirac unit of magnetic charge g = (137/2) e. The Paschen-Back effect in dyonium is discussed. From the dyonium model, Akers predicted the existence of a new η meson at 1814 MeV with I G(JPC) = 0+(0-+). Experimental evidence now confirms the existence of the meson resonance.
Global Mindsets: Exploration and Perspectives seeks to tackle a topic that is relatively new in research and practice, and is considered by many to be critical for firms seeking to conduct global business. It argues that multiple mindsets exist (across and within organizations), that they operate...... it is important for future scholars and managers and how it could be conceptualized. Global Mindsets: Exploration and Perspectives is split into two major sections; the first examines where the literature currently is with respect to the knowledge in the field and what conceptual frameworks guide the thinking......, and should help researchers determine areas of high potential research needs in the future. Given the fluid sense of global mindsets in action, the authors of this book have adopted a flexible and wide-ranging approach. Global Mindsets: Exploration and Perspectives includes conceptual chapters that push...
Global analysis of Ivlev's type predator-prey dynamic systems
XIAO Hai-bin
2007-01-01
Consider a class of Ivlev's type predator-prey dynamic systems with prey and predator both having linear density restricts. By using the qualitative methods of ODE,the global stability of positive equilibrium and existence and uniqueness of non-small amplitude stable limit cycle are obtained. Especially under certain conditions, it shows that existence and uniqueness of non-small amplitude stable limit cycle is equivalent to the local un-stability of positive equilibrium and the local stability of positive equilibrium implies its global stability. That is to say, the global dynamic of the system is entirely determined by the local stability of the positive equilibrium.
Zhang, Ting; Fang, Daoyuan
2008-03-01
In this paper, we study the free boundary problem for 1D compressible Navier-Stokes equations with density-dependent viscosity. We focus on the case where the viscosity coefficient vanishes on vacuum. We prove the global existence and uniqueness for discontinuous solutions to the Navier-Stokes equations when the initial density is a bounded variation function, and give a decay result for the density as t-->+[infinity].
Reutilizing Existing Library Space.
Davis, Marlys Cresap
1987-01-01
This discussion of the reutilization of existing library space reviews the decision process and considerations for implementation. Two case studies of small public libraries which reassigned space to better use are provided, including floor plans. (1 reference) (MES)
N. Andela
2013-05-01
Full Text Available Drylands, covering nearly 30% of the global land surface, are characterized by high climate variability and sensitivity to land management. Here, two satellite observed vegetation products were used to study the long-term (1988–2008 vegetation changes of global drylands: the widely used reflective-based Normalized Difference Vegetation Index (NDVI and the recently developed passive-microwave-based Vegetation Optical Depth (VOD. The NDVI is sensitive to the chlorophyll concentrations in the canopy and the canopy cover fraction, while the VOD is sensitive to vegetation water content of both leafy and woody components. Therefore it can be expected that using both products helps to better characterize vegetation dynamics, particularly over regions with mixed herbaceous and woody vegetation. Linear regression analysis was performed between antecedent precipitation and observed NDVI and VOD independently to distinguish the contribution of climatic and non-climatic drivers in vegetation variations. Where possible, the contributions of fire, grazing, agriculture and CO2 level to vegetation trends were assessed. The results suggest that NDVI is more sensitive to fluctuations in herbaceous vegetation, which primarily use shallow soil water whereas VOD is more sensitive to woody vegetation, which additionally can exploit deeper water stores. Globally, evidence is found for woody encroachment over drylands. In the arid drylands, woody encroachment seems to be at the expense of herbaceous vegetation and a global driver is interpreted. Trends in semi-arid drylands vary widely between regions, suggesting that local rather than global drivers caused most of the vegetation response. In savannas, besides precipitation, fire regime plays an important role in shaping trends. Our results demonstrate that NDVI and VOD provide complementary information, bringing new insights on vegetation dynamics.
N. Andela
2013-10-01
Full Text Available Drylands, covering nearly 30% of the global land surface, are characterized by high climate variability and sensitivity to land management. Here, two satellite-observed vegetation products were used to study the long-term (1988–2008 vegetation changes of global drylands: the widely used reflective-based Normalized Difference Vegetation Index (NDVI and the recently developed passive-microwave-based Vegetation Optical Depth (VOD. The NDVI is sensitive to the chlorophyll concentrations in the canopy and the canopy cover fraction, while the VOD is sensitive to vegetation water content of both leafy and woody components. Therefore it can be expected that using both products helps to better characterize vegetation dynamics, particularly over regions with mixed herbaceous and woody vegetation. Linear regression analysis was performed between antecedent precipitation and observed NDVI and VOD independently to distinguish the contribution of climatic and non-climatic drivers in vegetation variations. Where possible, the contributions of fire, grazing, agriculture and CO2 level to vegetation trends were assessed. The results suggest that NDVI is more sensitive to fluctuations in herbaceous vegetation, which primarily uses shallow soil water, whereas VOD is more sensitive to woody vegetation, which additionally can exploit deeper water stores. Globally, evidence is found for woody encroachment over drylands. In the arid drylands, woody encroachment appears to be at the expense of herbaceous vegetation and a global driver is interpreted. Trends in semi-arid drylands vary widely between regions, suggesting that local rather than global drivers caused most of the vegetation response. In savannas, besides precipitation, fire regime plays an important role in shaping trends. Our results demonstrate that NDVI and VOD provide complementary information and allow new insights into dryland vegetation dynamics.
Heinrich, Stuart
2012-01-01
Despite the success of physics in formulating mathematical theories that can predict the outcome of experiments, we have made remarkably little progress towards answering some of the most basic questions about our existence, such as: why does the universe exist? Why is the universe apparently fine-tuned to be able to support life? Why are the laws of physics so elegant? Why do we have three dimensions of space and one of time? How is it that the universe can be non-local and non-causal at the quantum scale, and why is there quantum randomness? In this paper, it is shown that all of these questions are answered if existence is relative, and moreover, it seems that we are logically bound to accept it.
This elusive objective existence
Mohrhoff, U
2004-01-01
Zurek's existential interpretation of quantum mechanics suffers from three classical prejudices, including the belief that space and time are intrinsically and infinitely differentiated. They compel him to relativize the concept of objective existence in two ways. The elimination of these prejudices makes it possible to recognize the quantum formalism's ontological implications - the relative and contingent reality of spatiotemporal distinctions and the extrinsic and finite spatiotemporal differentiation of the physical world - which in turn makes it possible to arrive at an unqualified objective existence. Contrary to a widespread misconception, viewing the quantum formalism as being fundamentally a probability algorithm does not imply that quantum mechanics is concerned with states of knowledge rather than states of Nature. On the contrary, it makes possible a complete and strongly objective description of the physical world that requires no reference to observers. What objectively exists, in a sense that r...
Relativity, Dimensionality, and Existence
Petkov, Vesselin
A 100 years have passed since the advent of special relativity and 2008 will mark another important to all relativists anniversary - 100 years since Minkowski gave his talk "Space and Time" on September 21, 1908 in which he proposed the unifi- cation of space and time into an inseparable entity - space-time. Although special relativity has been an enormously successful physical theory no progress has been made in clarifying the question of existence of the objects represented by two of its basic concepts - space-time and world lines (or worldtubes in the case of extended bodies). The major reason for this failure appears to be the physicists' tradition to call such questions of existence philosophical. This tradition, however, is not quite consistent. In Newtonian mechanics physicists believe that they describe real objects whenever they talk about particles - one of the basic concepts of Newtonian physics. The situation is the same in quantum physics - no one questions the existence of electrons, protons, etc. Then why should the question of existence of worldtubes (representing particles in relativity) be regarded as a philosophical question?
Laricchia, Savio; Constantin, Lucian A; Fabiano, Eduardo; Della Sala, Fabio
2014-01-14
We tested Laplacian-level meta-generalized gradient approximation (meta-GGA) noninteracting kinetic energy functionals based on the fourth-order gradient expansion (GE4). We considered several well-known Laplacian-level meta-GGAs from the literature (bare GE4, modified GE4, and the MGGA functional of Perdew and Constantin (Phys. Rev. B 2007,75, 155109)), as well as two newly designed Laplacian-level kinetic energy functionals (L0.4 and L0.6). First, a general assessment of the different functionals is performed to test them for model systems (one-electron densities, Hooke's atom, and different jellium systems) and atomic and molecular kinetic energies as well as for their behavior with respect to density-scaling transformations. Finally, we assessed, for the first time, the performance of the different functionals for subsystem density functional theory (DFT) calculations on noncovalently interacting systems. We found that the different Laplacian-level meta-GGA kinetic functionals may improve the description of different properties of electronic systems, but no clear overall advantage is found over the best GGA functionals. Concerning the subsystem DFT calculations, the here-proposed L0.4 and L0.6 kinetic energy functionals are competitive with state-of-the-art GGAs, whereas all other Laplacian-level functionals fail badly. The performance of the Laplacian-level functionals is rationalized thanks to a two-dimensional reduced-gradient and reduced-Laplacian decomposition of the nonadditive kinetic energy density.
Laricchia, S; Fabiano, E; Della Sala, F
2014-01-01
We test Laplacian-level meta-generalized gradient approximation (meta-GGA) non-interacting kinetic energy functionals based on the fourth-order gradient expansion (GE4). We consider several well known Laplacian-level meta-GGAs from literature (bare GE4, modified GE4, and the MGGA functional of Perdew and Constantin [Phys. Rev. B \\textbf{75},155109 (2007)]), as well as two newly designed Laplacian-level kinetic energy functionals (named L0.4 and L0.6). First, a general assessment of the different functionals is performed, testing them for model systems (one-electron densities, Hooke's atom and different jellium systems), atomic and molecular kinetic energies as well as for their behavior with respect to density-scaling transformations. Finally, we assess, for the first time, the performance of the different functionals for Subsystem Density Functional Theory (DFT) calculations on non-covalently interacting systems. We find that the different Laplacian-level meta-GGA kinetic functionals may improve the descript...
Density dependent neurodynamics.
Halnes, Geir; Liljenström, Hans; Arhem, Peter
2007-01-01
The dynamics of a neural network depends on density parameters at (at least) two different levels: the subcellular density of ion channels in single neurons, and the density of cells and synapses at a network level. For the Frankenhaeuser-Huxley (FH) neural model, the density of sodium (Na) and potassium (K) channels determines the behaviour of a single neuron when exposed to an external stimulus. The features of the onset of single neuron oscillations vary qualitatively among different regions in the channel density plane. At a network level, the density of neurons is reflected in the global connectivity. We study the relation between the two density levels in a network of oscillatory FH neurons, by qualitatively distinguishing between three regions, where the mean network activity is (1) spiking, (2) oscillating with enveloped frequencies, and (3) bursting, respectively. We demonstrate that the global activity can be shifted between regions by changing either the density of ion channels at the subcellular level, or the connectivity at the network level, suggesting that different underlying mechanisms can explain similar global phenomena. Finally, we model a possible effect of anaesthesia by blocking specific inhibitory ion channels.
1985-01-01
envisionment ) produced by GIZMO . ? In the envisionment , I s indicates the set of quantity—conditioned individuals that exists during a situa- tion... envisionment step by step . In START, the initial state, GIZMO deduces that heat flow occurs, since there is assumed to be a temperature difference between the...stov e GIZMO implements the basic operations of qualitative process theory, including an envisioner for makin g predictions and a program for
Hermeneutics as Embodied Existence
Marja Schuster RN, PhD
2013-02-01
Full Text Available This article explores the possibilities and limits of a hermeneutic way of being in the world, more specifically being a researcher as a part of human, embodied existence. Understanding existence as embodied highlights the subjectivity of a researcher. For a hermeneutic researcher this subjectivity is both a precondition for interpretation and something that might endanger the scientific endeavour. In this article, I examine the possibilities of combining Hans-Georg Gadamer's empathetic hermeneutics with Paul Ricoeur's critical hermeneutics as a means of both recognizing and, to some extent, controlling my subjectivity in the research process. With Gabriel Marcel I also argue for hermeneutics as an embodied experience. This is exemplified by my study with a focus on the existential dimensions of the nursing profession. The first part of the article introduces Marcel and his philosophical anthropology concerning our bodily existence as essential for shared lives with others. In the second part, this understanding of self and others is further developed by means of the hermeneutics of Gadamer and Ricoeur. In the third part, I present a way of applying hermeneutics in procedures for interviews, transcription, and analysis of data.
Existing chemicals: international activities.
Purchase, J F
1989-01-01
The standards of care used in the protection of the health and safety of people exposed to chemicals has increased dramatically in the last decade. Standards imposed by regulation and those adopted by industry have required a greater level of knowledge about the hazards of chemicals. In the E.E.C., the 6th amendment of the dangerous substances directive imposed the requirement that al new chemicals should be tested according to prescribed programme before introduction on to the market. The development of a European inventory of existing chemicals was an integral part of the 6th amendment. It has now become clear that increased standards of care referred to above must be applied to the chemicals on the inventory list. There is, however, a considerable amount of activity already under way in various international agencies. The OECD Chemicals Programme has been involved in considering the problem of existing chemicals for some time, and is producing a priority list and action programme. The International Programme on Chemical Safety produces international chemical safety cards, health and safety guides and environmental health criteria documents. The international register of potentially toxic compounds (part of UNEP) has prepared chemical data profiles on 990 compounds. The International Agency for Research on Cancer prepared monographs on the carcinogenic risk of chemicals to man. So far 42 volumes have been prepared covering about 900 substances. IARC and IPCS also prepare periodic reports on ongoing research on carcinogenicity or toxicity (respectively) of chemicals. The chemical industry through ECETOC (the European Chemical Industry Ecology and Toxicology Centre) has mounted a major initiative on existing chemicals. Comprehensive reviews of the toxicity of selected chemicals are published (Joint Assessment of Commodity Chemicals). In its technical report no. 30 ECETOC lists reviews and evaluations by major national and international organisations, which provides
Jedidi, Abdesslem
2015-11-13
Vibrational fingerprints of small PtnP2n (n = 1–5) clusters were computed from their low-lying structures located from a global exploration of their DFT potential energy surfaces with the GSAM code. Five DFT methods were assessed from the CCSD(T) wavenumbers of PtP2 species and CCSD relative energies of Pt2P4 structures. The eight first PtnP2n isomers found are reported. The vibrational computations reveal (i) the absence of clear signatures made by overtone or combination bands due to very weak mechanical and electrical anharmonicities and (ii) some significant and recurrent vibrational fingerprints in correlation with the different PP bonding situations in the PtnP2n structures.
Chen, P F
2016-01-01
After the {\\em Solar and Heliospheric Observatory} ({\\em SOHO}) was launched in 1996, the aboard Extreme Ultraviolet Imaging Telescope (EIT) observed a global coronal wave phenomenon, which was initially named "EIT wave" after the telescope. The bright fronts are immediately followed by expanding dimmings. It has been shown that the brightenings and dimmings are mainly due to plasma density increase and depletion, respectively. Such a spectacular phenomenon sparked long-lasting interest and debates. The debates were concentrated on two topics, one is about the driving source, and the other is about the nature of this wavelike phenomenon. The controversies are most probably because there may exist two types of large-scale coronal waves that were not well resolved before the {\\em Solar Dynamics Observatory} ({\\em SDO}) was launched: one is a piston-driven shock wave straddling over the erupting coronal mass ejection (CME), and the other is an apparently propagating front, which may correspond to the CME frontal...
Abbott, Timothy G; Charlton, David; Demaine, Erik D; Demaine, Martin L; Kominers, Scott D
2007-01-01
We prove that any finite collection of polygons of equal area has a common hinged dissection. That is, for any such collection of polygons there exists a chain of polygons hinged at vertices that can be folded in the plane continuously without self-intersection to form any polygon in the collection. This result settles the open problem about the existence of hinged dissections between pairs of polygons that goes back implicitly to 1864 and has been studied extensively in the past ten years. Our result generalizes and indeed builds upon the result from 1814 that polygons have common dissections (without hinges). We also extend our common dissection result to edge-hinged dissections of solid 3D polyhedra that have a common (unhinged) dissection, as determined by Dehn's 1900 solution to Hilbert's Third Problem. Our proofs are constructive, giving explicit algorithms in all cases. For a constant number of planar polygons, both the number of pieces and running time required by our construction are pseudopolynomial...
Lebesgue Sets Immeasurable Existence
Diana Marginean Petrovai
2012-12-01
Full Text Available It is well known that the notion of measure and integral were released early enough in close connection with practical problems of measuring of geometric ﬁgures. Notion of measure was outlined in the early 20th century through H. Lebesgue’s research, founder of the modern theory of measure and integral. It was developed concurrently a technique of integration of functions. Gradually it was formed a speciﬁc area todaycalled the measure and integral theory. Essential contributions to building this theory was made by a large number of mathematicians: C. Carathodory, J. Radon, O. Nikodym, S. Bochner, J. Pettis, P. Halmos and many others. In the following we present several abstract sets, classes of sets. There exists the sets which are not Lebesgue measurable and the sets which are Lebesgue measurable but are not Borel measurable. Hence B ⊂ L ⊂ P(X.
Wagner, Serge
2016-01-01
Physics textbooks present Minkowski space as an almost pure mathematical construct, without any explicit restriction on a domain where it is applicable in physics. Meanwhile, its physical meaning cannot but follow the same premises as those which underlies the special relativity theory: motion of free point particles and propagation of electromagnetic waves. However, the common formalism of coordinate transformations between any two inertial frames appears too ponderous to infer the existence of Minkowski space. For this reason, the time dilation and retardation, the contraction of the length along and the spatial invariance across the direction of relative motion of two frames are presented in a coordinate-free manner. This results in the transformation between two frames in the form of relationships between the time moments and the components of the position vector of a given event, along and across the directions of the frames' motion. The obtained transformation rules for the components of the position ve...
何云斌; 刘雪娇; 王知强; 万静; 李松
2016-01-01
The traditional K-means algorithm is sensitive to the selection of the initial clustering center, moreover the clustering number-k can not be confirmed beforehand. Then it is not conductive to the stability of the clustering. Considering this defection, a new improved algorithm—NDK-means(Nonuniqueness high-Density K-means) is proposed which is based on the global clustering center. In this algorithm, the highest-density points are not unique. To determine the radius, the standard deviation is applied to the new algorithm, then the initial clustering centers can be selected from a set of the high-density areas of points. When the highest-density points are not unique, the proposed new algorithm selects a set of initial clustering centers which are the furthest distance from the global clustering center. Besides, the new algorithm can determine the optimal number of cluster by selecting the BWP validity index. Finally, the experimental and analysis results show the new proposed method outperforms than the traditional K-means algorithm in terms of the validity and stability.%传统的K-means算法敏感于初始中心点的选取,并且无法事先确定准确的聚类数目k,不利于聚类结果的稳定性.针对传统K-means算法的以上不足,提出了基于全局中心的高密度不唯一的新方法——NDK-means,该方法通过标准差确定有效密度半径,并从高密度区域中选取具有代表性的样本点作为初始聚类中心.此外算法针对最高密度点不唯一的情况进行特别分析,选取距离全局中心最远的点集作为最优的初始中心点集合.在NDK-means算法基础上结合有效性指标BWP对聚类结果进行分析,从而解决了最佳有效聚类数目无法事先确定的不足.理论研究与实验结果表明所提方法的聚类结果具有更好的稳定性和可行性.
Colorectal cancer screening: a global overview of existing programmes.
Schreuders, Eline H; Ruco, Arlinda; Rabeneck, Linda; Schoen, Robert E; Sung, Joseph J Y; Young, Graeme P; Kuipers, Ernst J
2015-10-01
Colorectal cancer (CRC) ranks third among the most commonly diagnosed cancers worldwide, with wide geographical variation in incidence and mortality across the world. Despite proof that screening can decrease CRC incidence and mortality, CRC screening is only offered to a small proportion of the target population worldwide. Throughout the world there are widespread differences in CRC screening implementation status and strategy. Differences can be attributed to geographical variation in CRC incidence, economic resources, healthcare structure and infrastructure to support screening such as the ability to identify the target population at risk and cancer registry availability. This review highlights issues to consider when implementing a CRC screening programme and gives a worldwide overview of CRC burden and the current status of screening programmes, with focus on international differences.
Global existence and uniqueness of nonlinear evolutionary fluid equations
Qin, Yuming; Wang, Taige
2015-01-01
This book presents recent results on nonlinear evolutionary fluid equations such as the compressible (radiative) magnetohydrodynamics (MHD) equations, compressible viscous micropolar fluid equations, the full non-Newtonian fluid equations and non-autonomous compressible Navier-Stokes equations. These types of partial differential equations arise in many fields of mathematics, but also in other branches of science such as physics and fluid dynamics. This book will be a valuable resource for graduate students and researchers interested in partial differential equations, and will also benefit practitioners in physics and engineering.
Maicon Vendrúscolo
2010-02-01
Full Text Available The expansion of agricultural frontier through deforestation, adoption of mechanization and intensive use of inappropriate management practices, has promoted changes in the physical, chemical and biological properties of the soil, resulting in degradation processes, thus reducing productivity. Based on this, the objective the work was to evaluate the chemical characteristics and the global density of an Eutroferric Red Latosol of the experimental area of the Parana Catholic University, Toledo Campus. The experimental design used was casualized blocks with four replicates, in which the treatments were: millet, hairy vetch and control (spontaneous vegetation. The evaluations were: dry mass production, with the highest amount for millet (7.07 Mg ha¹, global soil density in which the lowest value was under control and the highest in hairy vetch; density of weeds population in which the control treatment had the highest value on; soil chemical characteristics, in which both hairy vetch and millet presented higher results compared to the control, being different in some nutrients, such as phosphorus, potassium and nitrogen.A expansão da fronteira agrícola através de desmatamentos, adoção de mecanização intensiva e uso de práticas de manejo inadequadas, tem promovido alterações nas propriedades físicas, químicas e biológicas do solo, resultando em processos de degradação, reduzindo desta maneira a produtividade. Com base no exposto, o objetivo do trabalho foi avaliar características químicas e densidade global de um Latossolo Vermelho Eutróferrico, da área experimental da Fazenda da Pontifícia Universidade Católica do Paraná, Campus Toledo, sob tratamentos do milheto (Pennisetum glaucum e da ervilhaca peluda (Vicia villosa como plantas de cobertura. O delineamento utilizado foi o de blocos ao acaso com quatro repetições, em que os tratamentos foram: milheto, ervilhaca peluda e testemunha (vegetação espontânea. As avalia
Global Solutions to the Coupled Chemotaxis-Fluid Equations
Duan, Renjun
2010-08-10
In this paper, we are concerned with a model arising from biology, which is a coupled system of the chemotaxis equations and the viscous incompressible fluid equations through transport and external forcing. The global existence of solutions to the Cauchy problem is investigated under certain conditions. Precisely, for the Chemotaxis-Navier-Stokes system over three space dimensions, we obtain global existence and rates of convergence on classical solutions near constant states. When the fluid motion is described by the simpler Stokes equations, we prove global existence of weak solutions in two space dimensions for cell density with finite mass, first-order spatial moment and entropy provided that the external forcing is weak or the substrate concentration is small. © Taylor & Francis Group, LLC.
Global health and the global economic crisis.
Benatar, Solomon R; Gill, Stephen; Bakker, Isabella
2011-04-01
Although the resources and knowledge for achieving improved global health exist, a new, critical paradigm on health as an aspect of human development, human security, and human rights is needed. Such a shift is required to sufficiently modify and credibly reduce the present dominance of perverse market forces on global health. New scientific discoveries can make wide-ranging contributions to improved health; however, improved global health depends on achieving greater social justice, economic redistribution, and enhanced democratization of production, caring social institutions for essential health care, education, and other public goods. As with the quest for an HIV vaccine, the challenge of improved global health requires an ambitious multidisciplinary research program.
U.S. Environmental Protection Agency — Road density is generally highly correlated with amount of developed land cover. High road densities usually indicate high levels of ecological disturbance. More...
Manners, Ian
2010-01-01
The mythology of the European Union (EU) in world politics can be told and untold in many different ways. This article focuses on the lore or stories of who did what to whom, the ideological projection of the past onto the present and the escapist pleasure of story telling in looking at the mytho......The mythology of the European Union (EU) in world politics can be told and untold in many different ways. This article focuses on the lore or stories of who did what to whom, the ideological projection of the past onto the present and the escapist pleasure of story telling in looking...... at the mythology of ‘global Europa' - the EU in the world. It concludes with a reflection on the way in which the many diverse myths of global Europa compete for daily attention, whether as lore, ideology, or pleasure. In this respect the mythology of global Europa is part of our everyday existence, part of the EU...
COMPETING CONCEPTIONS OF GLOBALIZATION
Leslie Sklair
2015-08-01
Full Text Available Globalization is a relatively new idea in the social sciences, although people who work in and write about the mass media, transnational corporations and international business have been using it for some time. The purpose of this paper is to critically review the ways in which sociologists and other social scientists use ideas of globalization and to evaluate the fruitfulness of these competing conceptions. The central feature of the idea of globalization is that many contemporary problems cannot be adequately studied at the level of nation-states, that is, in terms of each country and its inter-national relations. Instead, they need to be conceptualized in terms of global processes. Some have even gone so far as to predict that global forces, by which they usually mean transnational corporations and other global economic institutions, global culture or globalizing belief systems/ideologies of various types, or a combination of all of these, are becoming so powerful that the continuing existence of the nation-state is in serious doubt. This is not a necessary consequence of most theories of globalization. The argument of this paper is that much of the globalization literature is confused because not all those who use the term distinguish it clearly enough from internation-alization, and some writers appear to use the two terms interchangeably. I argue that a clear distinction must be drawn between the inter-national and the global. The hyphen in inter-national is to distinguish (inadequate conceptions of the global' founded on the existing even if changing system of nation-states, from (genuine conceptions of the global based on the emergence of global processes and a global system of social relations not founded on national characteristics or nation-states. This global system theory is the framework for my own research. Globalization studies can be categorized on the basis of four research clusters:1. The world-systems approach; 2. The global
Garnett, E S; Webber, C E; Coates, G
1977-01-01
The density of a defined volume of the human lung can be measured in vivo by a new noninvasive technique. A beam of gamma-rays is directed at the lung and, by measuring the scattered gamma-rays, lung density is calculated. The density in the lower lobe of the right lung in normal man during quiet...... breathing in the sitting position ranged from 0.25 to 0.37 g.cm-3. Subnormal values were found in patients with emphsema. In patients with pulmonary congestion and edema, lung density values ranged from 0.33 to 0.93 g.cm-3. The lung density measurement correlated well with the findings in chest radiographs...... but the lung density values were more sensitive indices. This was particularly evident in serial observations of individual patients....
李莹
2015-01-01
研究Banach空间中脉冲发展方程初值问题古典解的存在唯一性。采用逐段延拓的方法，在解析半群情形下，对脉冲函数不限制任何条件，得到无穷区间上一阶脉冲发展方程初值问题古典解的整体存在性以及唯一性结果。并将所得抽象结果运用到抛物型偏微分方程上。%The existence and uniqueness of classical solution about the initial value problems for impulsive evolution equations are discussed in Banach space. Without using any extra conditions for the impulsive functions ,the existence and uniqueness of classical global solutions are obtained about the initial value problems for first⁃order impulsive evolution equations on infinite interval by the method of extending interval when the semigroup is analytic. Moreover, the abstract results are applied to the parabolic partial differential equations.
Kierkegaardovo pojetí existence
Janatová, Kristýna
2016-01-01
The topic of the bachelor thesis is "Kierkegaard's conception of existence". There are both the life of the Danish philosopher Søren Kierkegaard and his philosophy discussed. The issue of human existence is analysed with its main three stages which are focused on aesthetics, ethics and religion. These stages of existence are at first described and afterwards compared with each other. The aesthetic represents the first stage of life and the religious stage is considered to be the highest aim o...
SUCIU TITUS
2013-02-01
Full Text Available The paper presents the close connection that exists between liberalism and globalization. In the first part wemake a presentation of the historical evolution of liberalism, starting with the classical economic liberalism continuingwith the neo-classical liberalism emphasizing neo-liberalism and within the latter one, the monetarism. In the secondpart of the paper we present the concept of globalization considered both from an economic and from a social point ofview. Among the winners of globalization we notice the transnational companies and among the losers, the underqualifiedworkers. As a main conclusion we consider that globalization has brought about an increase in the social –economic inequities
Ioku, Norisuke, E-mail: ioku@ehime-u.ac.jp [Ehime University, Graduate School of Science Engineering (Japan); Ruf, Bernhard; Terraneo, Elide [Università degli Studi di Milano, Dipartimento di Matematica “F. Enriques” (Italy)
2015-12-15
We consider a semilinear heat equation with exponential nonlinearity in ℝ{sup 2}. We prove that local solutions do not exist for certain data in the Orlicz space exp L{sup 2}(ℝ{sup 2}), even though a small data global existence result holds in the same space exp L{sup 2}(ℝ{sup 2}). Moreover, some suitable subclass of exp L{sup 2}(ℝ{sup 2}) for local existence and uniqueness is proposed.
Existence of the atmosphere attractor
李建平; 丑纪范
1997-01-01
The global asymptotic behavior of solutions for the equations of large-scale atmospheric motion with the non-stationary external forcing is studied in the infinite-dimensional Hilbert space. Based on the properties of operators of the equations, some energy inequalities and the uniqueness theorem of solutions are obtained. On the assumption that external forces are bounded, the exsitence of the global absorbing set and the atmosphere attractor is proved, and the characteristics of the decay of effect of initial field and the adjustment to the external forcing are revealed. The physical sense of the results is discussed and some ideas about climatic numerical forecast are elucidated.
THE EXISTENCE OF CONNECTING ORBITS
无
2011-01-01
In this paper,using the notion of an isolating block and Conley's attractor theory,an existence criterion of trajectories connecting a pair of invariant sets of ordinary differential equations is given.
Wladimir Antônio da Costa Garcia
2006-06-01
Full Text Available Temas como aquilo que há; o ser na sua singularidade (independentemente dos seus atributos ou das contingências; a relação entre escolha, necessidade e acaso; a relação entre possibilidade e impossibilidade (ou mesmo possíveis impossibilidades; e, por fim, neste ensaio, a relação entre caos e sistemas de ordem, sempre estiveram presentes, tanto na criação lírica como na reflexão filosófica. Logo, a existência não é privilégio do existencialismo. A noção de existência forma-se a partir daqueles temas: ela é secundária em relação aos pensamentos que a determinam. Trata-se, portanto, de uma “longa história, esta do sentido da existência” (DELEUZE, 1985. Desde o pensamento que se forma de uma culpa, desde o ressentimento e da vingança em torno da injustiça permanente do devir (quando a existência torna-se modificada pelos predicados, ou seja, niilista, à negação do todo e à absolvição da existência pela sua inocência (isto é, a afirmação do devir, o eterno retorno do ser do devir, etc., a noção de existência se desdobra. Sendo assim, o título deste trabalho, ao suspender aqueles sentidos estabelecidos, busca capturar a existência desde a potencialidade de suas relações com as configurações do poético.
Ethier, Wilfred J.
2002-01-01
This paper addresses a complex of globalization issues: the effect of globalization on the skill premium; the effect of globalization on unemployment; the relative importance of globalization and exogenous technical change; the effect of globalization on the ability of national governments to conduct independent social policies. Thinking about these topics has been dominated by a large empirical literature concluding that trade has played a relatively minor role in the rise of the skill premi...
Philipsen, Lotte; Baggesgaard, Mads Anders
2013-01-01
In order to understand globalization, we need to consider what globalization is not. That is, in order to understand the mechanisms and elements that work toward globalization, we must, in a sense, read against globalization, highlighting the limitations of the concept and its inherent conflicts....... Only by employing this as a critical practice will we be analytically able to gain a dynamic understanding of the forces of globalization as they unfold today and as they have developed historically....
MacMillan, Ian C; van Putten, Alexander B; McGrath, Rita Gunther
2003-05-01
Competition among multinationals these days is likely to be a three-dimensional game of global chess: The moves an organization makes in one market are designed to achieve goals in another in ways that aren't immediately apparent to its rivals. The authors--all management professors-call this approach "competing under strategic interdependence," or CSI. And where this interdependence exists, the complexity of the situation can quickly overwhelm ordinary analysis. Indeed, most business strategists are terrible at anticipating the consequences of interdependent choices, and they're even worse at using interdependency to their advantage. In this article, the authors offer a process for mapping the competitive landscape and anticipating how your company's moves in one market can influence its competitive interactions in others. They outline the six types of CSI campaigns--onslaughts, contests, guerrilla campaigns, feints, gambits, and harvesting--available to any multiproduct or multimarket corporation that wants to compete skillfully. They cite real-world examples such as the U.S. pricing battle Philip Morris waged with R.J. Reynolds--not to gain market share in the domestic cigarette market but to divert R.J. Reynolds's resources and attention from the opportunities Philip Morris was pursuing in Eastern Europe. And, using data they collected from their studies of consumer-products companies Procter & Gamble and Unilever, the authors describe how to create CSI tables and bubble charts that present a graphical look at the competitive landscape and that may uncover previously hidden opportunities. The CSI mapping process isn't just for global corporations, the authors explain. Smaller organizations that compete with a portfolio of products in just one national or regional market may find it just as useful for planning their next business moves.
Ferreira, Lizé-Mari; Eaby, Alan; Dillen, Jan
2017-09-30
The topology of the Coulomb potential density has been studied within the context of the theory of Atoms in Molecules and has been compared with the topologies of the electron density, the virial energy density and the Ehrenfest force density. The Coulomb potential density is found to be mainly structurally homeomorphic with the electron density. The Coulomb potential density reproduces the non-nuclear attractor which is observed experimentally in the molecular graph of the electron density of a Mg dimer, thus, for the first time ever providing an alternative and energetic foundation for the existence of this critical point. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Global dynamic evolution of the cold plasma inferred with neural networks
Zhelavskaya, Irina; Shprits, Yuri; Spasojevic, Maria
2017-04-01
The electron number density is a fundamental parameter of plasmas and is critical for the wave-particle interactions. Despite its global importance, the distribution of cold plasma and its dynamic dependence on solar wind conditions remains poorly quantified. Existing empirical models present statistical averages based on static geomagnetic parameters, but cannot reflect the dynamics of the highly structured and quickly varying plasmasphere environment, especially during times of high geomagnetic activity. Global imaging provides insights on the dynamics but quantitative inversion to electron number density has been lacking. We propose an empirical model for reconstruction of global dynamics of the cold plasma density distribution based only on solar wind data and geomagnetic indices. We develop a neural network that is capable of globally reconstructing the dynamics of the cold plasma density distribution for L shells from 2 to 6 and all local times. We utilize the density database obtained using the NURD algorithm [Zhelavskaya et al., 2016] in conjunction with solar wind data and geomagnetic indices to train the neural network. This study demonstrates how the global dynamics can be reconstructed from local in-situ observations by using machine learning tools. We describe aspects of the validation process in detail and discuss the selected inputs to the model and their physical implication.
Global Assimilation of Ionospheric Measurements (GAIM)
Schunk, R. W.; Scherliess, L.; Sojka, J. J.; Thompson, D. C.; Anderson, D. N.; Codrescu, M.; Minter, C.; Fuller-Rowell, T. J.; Heelis, R. A.; Hairston, M.; Howe, B. M.
2001-12-01
The ionosphere is a highly dynamic medium that can vary significantly from day to day and from hour to hour at a given location, and these variations can have detrimental effects on military and civilian systems. In an effort to minimize or circumvent the detrimental effects, a physics-based data assimilation model of the ionosphere and neutral atmosphere is under development with funding from the DoD MURI program. Two university consortia are involved, with USU and USC as the lead institutions. When completed, the GAIM (Global Assimilation of Ionospheric Measurements) model will provide specifications and forecasts on a spatial grid that can be global, regional, or local (50 km x 50 km). GAIM will use a physics-based ionosphere-plasmasphere model and a Kalman filter as a basis for assimilating a diverse set of real-time (or near real-time) measurements. Some of the data to be assimilated include in situ density measurements from satellites, ionosonde electron density profiles, occultation data, ground-based GPS TECs, TECs between ground stations and LEO satellites with radio beacons, and line-of-sight UV emissions from selected satellites. The resulting specifications and forecasts will be in the form of 3-dimensional electron density distributions from 90 km to geosynchronous altitude (35,000 km). An initial form of GAIM already exists and recent results from the USU consortium will be presented.
[Does Stendhal's syndrome exist really?].
Valtueña Borque, Oscar
2009-01-01
The author, Medical Doctor and Master in Art History, dicusses the real existence of the so called by the Florentine MD Magherini Stendhal syndrome, first time published in 1980 to put out the sickness that some tourists in their Florentia visit suffered, because the big beauty they founded in the city, as the French writter Stendahl suffered two centuries ago.
Li, Peter Ping
2013-01-01
Global strategy differs from domestic strategy in terms of content and process as well as context and structure. The content of global strategy can contain five key elements, while the process of global strategy can have six major stages. These are expounded below. Global strategy is influenced...... by rich and complementary local contexts with diverse resource pools and game rules at the national level to form a broad ecosystem at the global level. Further, global strategy dictates the interaction or balance between different entry strategies at the levels of internal and external networks....
Fermion N-representability for prescribed density and paramagnetic current density
Tellgren, Erik I; Kvaal, Simen; Helgaker, Trygve
2014-01-01
The $N$-representability problem is the problem of determining whether or not there exists $N$-particle states with some prescribed property. Here we report an affirmative solution to the fermion $N$-representability problem when both the density and paramagnetic current density are prescribed. This problem arises in current-density functional theory and is a generalization of the well-studied corresponding problem (only the density prescribed) in density functional theory. Given any density ...
The EXIST Mission Concept Study
Fishman, Gerald J.; Grindlay, J.; Hong, J.
2008-01-01
EXIST is a mission designed to find and study black holes (BHs) over a wide range of environments and masses, including: 1) BHs accreting from binary companions or dense molecular clouds throughout our Galaxy and the Local Group, 2) supermassive black holes (SMBHs) lying dormant in galaxies that reveal their existence by disrupting passing stars, and 3) SMBHs that are hidden from our view at lower energies due to obscuration by the gas that they accrete. 4) the birth of stellar mass BHs which is accompanied by long cosmic gamma-ray bursts (GRBs) which are seen several times a day and may be associated with the earliest stars to form in the Universe. EXIST will provide an order of magnitude increase in sensitivity and angular resolution as well as greater spectral resolution and bandwidth compared with earlier hard X-ray survey telescopes. With an onboard optical-infra red (IR) telescope, EXIST will measure the spectra and redshifts of GRBs and their utility as cosmological probes of the highest z universe and epoch of reionization. The mission would retain its primary goal of being the Black Hole Finder Probe in the Beyond Einstein Program. However, the new design for EXIST proposed to be studied here represents a significant advance from its previous incarnation as presented to BEPAC. The mission is now less than half the total mass, would be launched on the smallest EELV available (Atlas V-401) for a Medium Class mission, and most importantly includes a two-telescope complement that is ideally suited for the study of both obscured and very distant BHs. EXIST retains its very wide field hard X-ray imaging High Energy Telescope (HET) as the primary instrument, now with improved angular and spectral resolution, and in a more compact payload that allows occasional rapid slews for immediate optical/IR imaging and spectra of GRBs and AGN as well as enhanced hard X-ray spectra and timing with pointed observations. The mission would conduct a 2 year full sky survey in
Cluster pre-existence probability
Rajeswari, N.S.; Vijayaraghavan, K.R.; Balasubramaniam, M. [Bharathiar University, Department of Physics, Coimbatore (India)
2011-10-15
Pre-existence probability of the fragments for the complete binary spectrum of different systems such as {sup 56}Ni, {sup 116}Ba, {sup 226}Ra and {sup 256}Fm are calculated, from the overlapping part of the interaction potential using the WKB approximation. The role of reduced mass as well as the classical hydrodynamical mass in the WKB method is analysed. Within WKB, even for negative Q -value systems, the pre-existence probability is calculated. The calculations reveal rich structural information. The calculated results are compared with the values of preformed cluster model of Gupta and collaborators. The mass asymmetry motion is shown here for the first time as a part of relative separation motion. (orig.)
Existence of undiscovered Uranian satellites
Boice, D.C.
1986-04-01
Structure in the Uranian ring system as observed in recent occultations may contain indirect evidence for the existence of undiscovered satellites. Using the Alfven and Arrhenius (1975, 1976) scenario for the formation of planetary systems, the orbital radii of up to nine hypothetical satellites interior to Miranda are computed. These calculations should provide interesting comparisons when the results from the Voyager 2 encounter with Uranus are made public. 15 refs., 1 fig., 1 tab.
Narula, Rajneesh
Technology and globalization are interdependent processes. Globalization has a fundamental influence on the creation and diffusion of technology, which, in turn, affects the interdependence of firms and locations. This volume examines the international aspect of this interdependence at two levels...
... globalhealth/what/default.htm) CDC protects Americans through global health. frame support disabled and/or not supported ... Public Health Emergencies More stories Infographic More infographics Global Health & You OUTBREAKS DISEASES & CONDITIONS TRAVEL CDC JOBS ...
Vivi Triana
2008-03-01
Full Text Available Pemanasan global (global warming pada dasarnya merupakan fenomena peningkatan temperature global dari tahun ke tahun karena terjadinya efek rumah kaca (greenhouse effect yang disebabkan oleh meningkatnya emisi gas-gas seperti karbondioksida (CO2, metana (CH4, dinitrooksida (N2O dan CFC sehingga energy matahari terperangkap dalam atmosfer bumi. Berbagai literatur menunjukkan kenaikan temperatur global termasuk Indonesia yang terjadi pada kisaran 1,5 – 40 °C pada akhir abad 21.
Longstreet, Wilma S., Ed.
1988-01-01
This issue contains an introduction ("The Promise and Perplexity of Globalism," by W. Longstreet) and seven articles dedicated to exploring the meaning of global education for today's schools. "Global Education: An Overview" (J. Becker) develops possible definitions, identifies objectives and skills, and addresses questions and…
1997
This document contains four papers from a symposium on global human resource development (HRD). "Globalization of Human Resource Management (HRM) in Government: A Cross-Cultural Perspective" (Pan Suk Kim) relates HRM to national cultures and addresses its specific functional aspects with a unique dimension in a global organization.…
Existence and non-existence results for a nonlinear heat equation
Canan Celik
2007-02-01
Full Text Available In this study, we consider the nonlinear heat equation $$displaylines{ u_{t}(x,t = Delta u(x,t + u(x,t^p quad hbox{in } Omega imes (0,T,cr Bu(x,t = 0 quad hbox{on } partialOmega imes (0,T,cr u(x,0 = u_0(x quad hbox{in } Omega,}$$ with Dirichlet and mixed boundary conditions, where $Omega subset mathbb{R}^n$ is a smooth bounded domain and $p = 1+ 2 /n$ is the critical exponent. For an initial condition $u_0 in L^1$, we prove the non-existence of local solution in $L^1$ for the mixed boundary condition. Our proof is based on comparison principle for Dirichlet and mixed boundary value problems. We also establish the global existence in $L^{1+epsilon}$ to the Dirichlet problem, for any fixed $epsilon > 0$ with $|u_0|_{1+epsilon}$ sufficiently small.
Douglas, Ian
2011-01-01
The concept of usability has become an increasingly important consideration in the design of all kinds of technology. As more products are aimed at global markets and developed through internationally distributed teams, usability design needs to be addressed in global terms. Interest in usability as a design issue and specialist area of research and education has developed steadily in North America and Europe since the 1980's. However, it is only over the last ten years that it has emerged as a global concern. Global Usability provides an introduction to the important issues in globalizing des
Saddle scars Existence and applications
Mendes, R V
1998-01-01
A quantum scar is a wave function which displays an high intensity in the region of a classical unstable periodic orbit. Saddle scars are states related to the unstable harmonic motions along the stable manifold of a saddle point of the potential. Using a semiclassical method it is shown that, independently of the overall structure of the potential, the local dynamics of the saddle point is sufficient to insure the general existence of this type of scars and their factorized structure is obtained. Potentially useful situations are identified, where these states appear (directly or in disguise) and might be used for quantum control purposes.
Partition density functional theory
Nafziger, Jonathan
Partition density functional theory (PDFT) is a method for dividing a molecular electronic structure calculation into fragment calculations. The molecular density and energy corresponding to Kohn Sham density-functional theory (KS-DFT) may be exactly recovered from these fragments. Each fragment acts as an isolated system except for the influence of a global one-body 'partition' potential which deforms the fragment densities. In this work, the developments of PDFT are put into the context of other fragment-based density functional methods. We developed three numerical implementations of PDFT: One within the NWChem computational chemistry package using basis sets, and the other two developed from scratch using real-space grids. It is shown that all three of these programs can exactly reproduce a KS-DFT calculation via fragment calculations. The first of our in-house codes handles non-interacting electrons in arbitrary one-dimensional potentials with any number of fragments. This code is used to explore how the exact partition potential changes for different partitionings of the same system and also to study features which determine which systems yield non-integer PDFT occupations and which systems are locked into integer PDFT occupations. The second in-house code, CADMium, performs real-space calculations of diatomic molecules. Features of the exact partition potential are studied for a variety of cases and an analytical formula determining singularities in the partition potential is derived. We introduce an approximation for the non-additive kinetic energy and show how this quantity can be computed exactly. Finally a PDFT functional is developed to address the issues of static correlation and delocalization errors in approximations within DFT. The functional is applied to the dissociation of H2 + and H2.
Turbulence: does energy cascade exist?
Josserand, Christophe; Lehner, Thierry; Pomeau, Yves
2016-01-01
To answer the question whether a cascade of energy exists or not in turbulence, we propose a set of correlation functions able to test if there is an irreversible transfert of energy, step by step, from large to small structures. These tests are applied to real Eulerian data of a turbulent velocity flow, taken in the wind grid tunnel of Modane, and also to a prototype model equation for wave turbulence. First we demonstrate the irreversible character of the flow by using multi-time correlation function at a given point of space. Moreover the unexpected behavior of the test function leads us to connect irreversibility and finite time singularities (intermittency). Secondly we show that turbulent cascade exists, and is a dynamical process, by using a test function depending on time and frequency. The cascade shows up only in the inertial domain where the kinetic energy is transferred more rapidly (on average) from the wavenumber $k_{1}$ to $k_{2}$ than from $k_{1}$ to $k'_{2}$ larger than $k_{2}$.
Sacks, Frank M; Hermans, Michel P; Fioretto, Paola; Valensi, Paul; Davis, Timothy; Horton, Edward; Wanner, Christoph; Al-Rubeaan, Khalid; Aronson, Ronnie; Barzon, Isabella; Bishop, Louise; Bonora, Enzo; Bunnag, Pongamorn; Chuang, Lee-Ming; Deerochanawong, Chaicharn; Goldenberg, Ronald; Harshfield, Benjamin; Hernández, Cristina; Herzlinger-Botein, Susan; Itoh, Hiroshi; Jia, Weiping; Jiang, Yi-Der; Kadowaki, Takashi; Laranjo, Nancy; Leiter, Lawrence; Miwa, Takashi; Odawara, Masato; Ohashi, Ken; Ohno, Atsushi; Pan, Changyu; Pan, Jiemin; Pedro-Botet, Juan; Reiner, Zeljko; Rotella, Carlo Maria; Simo, Rafael; Tanaka, Masami; Tedeschi-Reiner, Eugenia; Twum-Barima, David; Zoppini, Giacomo; Carey, Vincent J
2014-03-04
Microvascular renal and retinal diseases are common major complications of type 2 diabetes mellitus. The relation between plasma lipids and microvascular disease is not well established. The case subjects were 2535 patients with type 2 diabetes mellitus with an average duration of 14 years, 1891 of whom had kidney disease and 1218 with retinopathy. The case subjects were matched for diabetes mellitus duration, age, sex, and low-density lipoprotein cholesterol to 3683 control subjects with type 2 diabetes mellitus who did not have kidney disease or retinopathy. The study was conducted in 24 sites in 13 countries. The primary analysis included kidney disease and retinopathy cases. Matched analysis was performed by use of site-specific conditional logistic regression in multivariable models that adjusted for hemoglobin A1c, hypertension, and statin treatment. Mean low-density lipoprotein cholesterol concentration was 2.3 mmol/L. The microvascular disease odds ratio increased by a factor of 1.16 (95% confidence interval, 1.11-1.22) for every 0.5 mmol/L (≈1 quintile) increase in triglycerides or decreased by a factor of 0.92 (0.88-0.96) for every 0.2 mmol/L (≈1 quintile) increase in high-density lipoprotein cholesterol. For kidney disease, the odds ratio increased by 1.23 (1.16-1.31) with triglycerides and decreased by 0.86 (0.82-0.91) with high-density lipoprotein cholesterol. Retinopathy was associated with triglycerides and high-density lipoprotein cholesterol in matched analysis but not significantly after additional adjustment. Diabetic kidney disease is associated worldwide with higher levels of plasma triglycerides and lower levels of high-density lipoprotein cholesterol among patients with good control of low-density lipoprotein cholesterol. Retinopathy was less robustly associated with these lipids. These results strengthen the rationale for studying dyslipidemia treatment to prevent diabetic microvascular disease.
Global solution for a chemotactic haptotactic model of cancer invasion
Tao, Youshan; Wang, Mingjun
2008-10-01
This paper deals with a mathematical model of cancer invasion of tissue recently proposed by Chaplain and Lolas. The model consists of a reaction-diffusion-taxis partial differential equation (PDE) describing the evolution of tumour cell density, a reaction-diffusion PDE governing the evolution of the proteolytic enzyme concentration and an ordinary differential equation modelling the proteolysis of the extracellular matrix (ECM). In addition to random motion, the tumour cells are directed not only by haptotaxis (cellular locomotion directed in response to a concentration gradient of adhesive molecules along the ECM) but also by chemotaxis (cellular locomotion directed in response to a concentration gradient of the diffusible proteolytic enzyme). In one space dimension, the global existence and uniqueness of a classical solution to this combined chemotactic-haptotactic model is proved for any chemotactic coefficient χ > 0. In two and three space dimensions, the global existence is proved for small χ/μ (where μ is the logistic growth rate of the tumour cells). The fundamental point of proof is to raise the regularity of a solution from L1 to Lp (p > 1). Furthermore, the existence of blow-up solutions to a sub-model in two space dimensions for large χ shows, to some extent, that the condition that χ/μ is small is necessary for the global existence of a solution to the full model.
Degenerate Density Perturbation Theory
Palenik, Mark C
2016-01-01
Fractional occupation numbers can be used in density functional theory to create a symmetric Kohn-Sham potential, resulting in orbitals with degenerate eigenvalues. We develop the corresponding perturbation theory and apply it to a system of $N_d$ degenerate electrons in a harmonic oscillator potential. The order-by-order expansions of both the fractional occupation numbers and unitary transformations within the degenerate subspace are determined by the requirement that a differentiable map exists connecting the initial and perturbed states. Using the X$\\alpha$ exchange-correlation (XC) functional, we find an analytic solution for the first-order density and first through third-order energies as a function of $\\alpha$, with and without a self-interaction correction. The fact that the XC Hessian is not positive definite plays an important role in the behavior of the occupation numbers.
Degenerate density perturbation theory
Palenik, Mark C.; Dunlap, Brett I.
2016-09-01
Fractional occupation numbers can be used in density functional theory to create a symmetric Kohn-Sham potential, resulting in orbitals with degenerate eigenvalues. We develop the corresponding perturbation theory and apply it to a system of Nd degenerate electrons in a harmonic oscillator potential. The order-by-order expansions of both the fractional occupation numbers and unitary transformations within the degenerate subspace are determined by the requirement that a differentiable map exists connecting the initial and perturbed states. Using the X α exchange-correlation (XC) functional, we find an analytic solution for the first-order density and first- through third-order energies as a function of α , with and without a self-interaction correction. The fact that the XC Hessian is not positive definite plays an important role in the behavior of the occupation numbers.
Gravitational Global Monopoles with Horizons
Maison, D
1999-01-01
We give arguments for the existence of ``radial excitations'' of gravitational global monopoles with any number of zeros of the Higgs field and present numerical results for solutions with up to two zeros. All these solutions possess a de Sitter like cosmological horizon, outside of which they become singular. In addition we study corresponding static ``hairy'' black hole solutions, representing black holes sitting inside a global monopole core. In particular, we determine their existence domains as a function of their horizon radius rh.
Globalization and Productivity
Hayakawa, Kazunobu; Machikita, Tomohiro
2012-01-01
Recent empirical studies which utilize plant- or establishment-level data to examine globalization's impact on productivity have discovered many causal mechanisms involved in globalization's impact on firms’ productivity. Because these pathways have been broad, there have been few attempts...... to summarize the several and detailed mechanisms of self-selection and learning at the same time. This paper examines seven pathways so that the clear-cut consequences of the broad picture of globalization become visible. This strategy is useful for detecting missing links within and across the existing...... studies as well as for finding possible synergy effects among different mechanisms. Insightful policy implications may be derived from the comprehensive comparisons between the seven different pathways of globalization....
Straightening: existence, uniqueness and stability.
Destrade, M; Ogden, R W; Sgura, I; Vergori, L
2014-04-08
One of the least studied universal deformations of incompressible nonlinear elasticity, namely the straightening of a sector of a circular cylinder into a rectangular block, is revisited here and, in particular, issues of existence and stability are addressed. Particular attention is paid to the system of forces required to sustain the large static deformation, including by the application of end couples. The influence of geometric parameters and constitutive models on the appearance of wrinkles on the compressed face of the block is also studied. Different numerical methods for solving the incremental stability problem are compared and it is found that the impedance matrix method, based on the resolution of a matrix Riccati differential equation, is the more precise.
Straightening: existence, uniqueness and stability
Destrade, M.; Ogden, R. W.; Sgura, I.; Vergori, L.
2014-01-01
One of the least studied universal deformations of incompressible nonlinear elasticity, namely the straightening of a sector of a circular cylinder into a rectangular block, is revisited here and, in particular, issues of existence and stability are addressed. Particular attention is paid to the system of forces required to sustain the large static deformation, including by the application of end couples. The influence of geometric parameters and constitutive models on the appearance of wrinkles on the compressed face of the block is also studied. Different numerical methods for solving the incremental stability problem are compared and it is found that the impedance matrix method, based on the resolution of a matrix Riccati differential equation, is the more precise. PMID:24711723
Local Existence of Spinor Potentials
Andersson, F
1999-01-01
We present a new, simple proof of existence for the Lanczos spinor potential in 3+1 dimensions that introduces a potential $T_{ABCD}= T_{(ABC)D}$ of the Lanczos potential together with several generalizations to other index configurations and metric signatures. The potential $T_{ABCD}$ can also be used to express, in a concise way, the gauge freedom left in the Lanczos potential after the differential gauge has been specified. We consider Einstein spacetimes and prove that in those spacetimes any symmetric (3,1)-spinor possesses a symmetric potential $H_{ABA'B'}$. Potentials of this type have earlier occurred in some special cases investigated e.g., by Torres del Castillo, Bergqvist and ourselves.
Does the polystomatic gland exist?
Imai, M; Shibata, T; Moriguchi, K; Kinbara, M
1989-03-01
According to the P.N.A., the N.A.J. and some scholars, the sublingual gland has the ductus sublingualis major and ductus sublinguales minores. This means that the gland is a polystomatic gland. We intended to determine whether the so-called polystomatic gland exists or not. 1. According to the P.N.A., the N.A.J. and some scholars, the gl. sublingualis has the ductus sublingualis major and ductus sublinguales minores. This means the gland is a polystomatic gland. However, the formation of one gland with plural excretory ducts is embryologically impossible, in other words, the polystomatic gland does not exist. 2. Many scholars described that the gl. sublingualis was composed of the gl. sublingualis major and g11. sublinguales minores. However, they are completely different kinds of glands. Accordingly, we suggest the terms for these glands: the g1. sublingualis and its ductus sublingualis ("major" is useless), the g11. sublinguales minores and their ductus sublinguales minores. 3. The N.A.V.J. and some scholars use the term g1. sublingualis polystomatica or parvicanalaris. However, this is a group of a number of independent glands each of which has its own excretory duct. Such a gland should not be regarded as a single gland. We suggest that the term g11. sublinguales minores and their excretory ducts should be replaced with the term the ductus sublinguales minores. 4. The g1. lingualis anterior, g1. retromolaris and g1. lacrimalis are not single glands but a group of several independent glands each of which has its own excretory duct. Accordingly, they should be termed the g11. linguales anteriores, g11. retromolares and g11. lacrimales such as the g11. labiales, g11. buccales and g11. palatinae.
Global Sales Training's Balancing Act
Boehle, Sarah
2010-01-01
A one-size-fits-all global sales strategy that fails to take into account the cultural, regulatory, geographic, and economic differences that exist across borders is a blueprint for failure. For training organizations tasked with educating globally dispersed sales forces, the challenge is adapting to these differences while simultaneously…
Martin, Greg
2005-04-22
This debut editorial of Globalization and Health introduces the journal, briefly delineating its goals and objectives and outlines its scope of subject matter. 'Open Access' publishing is expected to become an increasingly important format for peer reviewed academic journals and that Globalization and Health is 'Open Access' is appropriate. The rationale behind starting a journal dedicated to globalization and health is three fold:Firstly: Globalization is reshaping the social geography within which we might strive to create health or prevent disease. The determinants of health - be they a SARS virus or a predilection for fatty foods - have joined us in our global mobility. Driven by economic liberalization and changing technologies, the phenomenon of 'access' is likely to dominate to an increasing extent the unfolding experience of human disease and wellbeing.Secondly: Understanding globalization as a subject matter itself needs certain benchmarks and barometers of its successes and failings. Health is one such barometer. It is a marker of social infrastructure and social welfare and as such can be used to either sound an alarm or give a victory cheer as our interconnectedness hurts and heals the populations we serve.And lastly: In as much as globalization can have an effect on health, it is also true that health and disease has an effect on globalization as exemplified by the existence of quarantine laws and the devastating economic effects of the AIDS pandemic.A balanced view would propose that the effects of globalization on health (and health systems) are neither universally good nor bad, but rather context specific. If the dialogue pertaining to globalization is to be directed or biased in any direction, then it must be this: that we consider the poor first.
Martin Greg
2005-04-01
Full Text Available Abstract This debut editorial of Globalization and Health introduces the journal, briefly delineating its goals and objectives and outlines its scope of subject matter. 'Open Access' publishing is expected to become an increasingly important format for peer reviewed academic journals and that Globalization and Health is 'Open Access' is appropriate. The rationale behind starting a journal dedicated to globalization and health is three fold: Firstly: Globalization is reshaping the social geography within which we might strive to create health or prevent disease. The determinants of health – be they a SARS virus or a predilection for fatty foods – have joined us in our global mobility. Driven by economic liberalization and changing technologies, the phenomenon of 'access' is likely to dominate to an increasing extent the unfolding experience of human disease and wellbeing. Secondly: Understanding globalization as a subject matter itself needs certain benchmarks and barometers of its successes and failings. Health is one such barometer. It is a marker of social infrastructure and social welfare and as such can be used to either sound an alarm or give a victory cheer as our interconnectedness hurts and heals the populations we serve. And lastly: In as much as globalization can have an effect on health, it is also true that health and disease has an effect on globalization as exemplified by the existence of quarantine laws and the devastating economic effects of the AIDS pandemic. A balanced view would propose that the effects of globalization on health (and health systems are neither universally good nor bad, but rather context specific. If the dialogue pertaining to globalization is to be directed or biased in any direction, then it must be this: that we consider the poor first.
Chinese Entrepreneurs Go Global
Daniel Zhou
2012-02-01
Full Text Available China may be on the tipping point of explosive global growth. In response to changes in the global economy and an economic slowdown domestically, hundreds of thousands of Chinese SMEs are being encouraged to “go global” by their central and local governments. To a Chinese company, going global requires the expansion of its existing business in other countries or the development of new ventures with partners operating in other countries. Explosive growth in China may be possible, but it will depend on an appropriate strategy for going global. For a country that has firmly established itself as an international manufacturing hub, going global requires a shift in its entrepreneurial capacity, which is the focus of this article. We first assess the current situation in China to understand its current entrepreneurial focus and capacity, as well as the impetus for change. Next, we contrast the Kirznerian and Schumpeterian views of entrepreneurship to illustrate that – to go global – Chinese entrepreneurs must shift from an emphasis on exploiting pricing inefficiencies (i.e., Kirznerian entrepreneurship to an emphasis on innovation (i.e., Schumpeterian entrepreneurship. Finally, we examine unique characteristics of the business environment and culture in China, which are likely to impact the ability of Chinese entrepreneurs to go global.
Quantum nonlocality does not exist.
Tipler, Frank J
2014-08-05
Quantum nonlocality is shown to be an artifact of the Copenhagen interpretation, in which each observed quantity has exactly one value at any instant. In reality, all physical systems obey quantum mechanics, which obeys no such rule. Locality is restored if observed and observer are both assumed to obey quantum mechanics, as in the many-worlds interpretation (MWI). Using the MWI, I show that the quantum side of Bell's inequality, generally believed nonlocal, is really due to a series of three measurements (not two as in the standard, oversimplified analysis), all three of which have only local effects. Thus, experiments confirming "nonlocality" are actually confirming the MWI. The mistaken interpretation of nonlocality experiments depends crucially on a question-begging version of the Born interpretation, which makes sense only in "collapse" versions of quantum theory, about the meaning of the modulus of the wave function, so I use the interpretation based on the MWI, namely that the wave function is a world density amplitude, not a probability amplitude. This view allows the Born interpretation to be derived directly from the Schrödinger equation, by applying the Schrödinger equation to both the observed and the observer.
Existe sujeito em Michel Maffesoli?
Marli Appel da Silva
2010-06-01
Full Text Available Este ensaio discute a concepção de sujeito na abordagem teórica de Michel Maffesoli. As ideias desse autor estão em voga em alguns meios acadêmicos no Brasil e são difundidas por algumas mídias de grande circulação nacional. Entretanto, ao longo de suas obras, os pressupostos que definem quem é o sujeito maffesoliano se encontram pouco clarificados. Portanto, para alcançar o objetivo a que se propõe, este ensaio desenvolve uma análise da epistemologia e da ontologia maffesoliana com a finalidade de compreender as origens dos pressupostos desse autor, ou seja, as teorias e os autores em que Maffesoli se baseou para desenvolver uma visão de sujeito. Com essa compreensão, pretende-se responder à questão: existe sujeito na abordagem teórica de Maffesoli.
Does Metabolically Healthy Obesity Exist?
Muñoz-Garach, Araceli; Cornejo-Pareja, Isabel; Tinahones, Francisco J.
2016-01-01
The relationship between obesity and other metabolic diseases have been deeply studied. However, there are clinical inconsistencies, exceptions to the paradigm of “more fat means more metabolic disease”, and the subjects in this condition are referred to as metabolically healthy obese (MHO).They have long-standing obesity and morbid obesity but can be considered healthy despite their high degree of obesity. We describe the variable definitions of MHO, the underlying mechanisms that can explain the existence of this phenotype caused by greater adipose tissue inflammation or the different capacity for adipose tissue expansion and functionality apart from other unknown mechanisms. We analyze whether these subjects improve after an intervention (traditional lifestyle recommendations or bariatric surgery) or if they stay healthy as the years pass. MHO is common among the obese population and constitutes a unique subset of characteristics that reduce metabolic and cardiovascular risk factors despite the presence of excessive fat mass. The protective factors that grant a healthier profile to individuals with MHO are being elucidated. PMID:27258304
Busck, Ole Gunni
2015-01-01
Øgede globale økologiske distributionskonflikter i kraft af neoliberal globalisering drevet af kravet om økonomisk vækst......Øgede globale økologiske distributionskonflikter i kraft af neoliberal globalisering drevet af kravet om økonomisk vækst...
Jensen, Niels Rosendal
Antologien handler om "demokratiproblemer i den globale sammenhæng" (del I) og "demokratiproblemer i uddannelse og for de offentligt ansatte" (del II), bundet sammen af et mellemstykke, der rækker ud mod begge poler både det globale og det lokale ved at knytte det til forholdet mellem marked...
2009-01-01
The current global financial situation bluntly and brutally brings home the fact that the global and local are closely connected in times of opportunity as well as crises. The articles in this issue of Asia Insights are about ontra-action between Asia, particularly China, and the Nordic countries...
... Information › Bone Density Exam/Testing › Low Bone Density Low Bone Density Low bone density is when your ... compared to people with normal bone density. Detecting Low Bone Density A bone density test will determine ...
GLOBAL IMBALANCES, CRISIS AND THE LACK OF GLOBAL GOVERNANCE
VIOLETA GIANINA DRAGOTĂ
2012-11-01
Full Text Available While briefly shrinking during the global crisis, global imbalances in trade and financial flows and their underlying systemic causes have not gone away. The current monetary non-order causes developing countries to adopt defensive strategies against fickle markets and allows developed countries to engage in beggar-thy-neighbour strategies, with a reliance on exports serving to offset their failure to manage domestic demand. Global imbalances are a symptom of existing systemic governance shortcomings. They can only be properly addressed by global governance reform and proper international policy coordination.
Existence domains of dust-acoustic solitons and supersolitons
Maharaj, S. K. [South African National Space Agency (SANSA) Space Science, PO Box 32, Hermanus 7200 (South Africa); Bharuthram, R. [University of the Western Cape, Robert Sobukwe Road, Bellville 7535 (South Africa); Singh, S. V.; Lakhina, G. S. [Indian Institute of Geomagnetism, New Panvel, Navi Mumbai 410218 (India)
2013-08-15
Using the Sagdeev potential method, the existence of large amplitude dust-acoustic solitons and supersolitons is investigated in a plasma comprising cold negative dust, adiabatic positive dust, Boltzmann electrons, and non-thermal ions. This model supports the existence of positive potential supersolitons in a certain region in parameter space in addition to regular solitons having negative and positive potentials. The lower Mach number limit for supersolitons coincides with the occurrence of double layers whereas the upper limit is imposed by the constraint that the adiabatic positive dust number density must remain real valued. The upper Mach number limits for negative potential (positive potential) solitons coincide with limiting values of the negative (positive) potential for which the negative (positive) dust number density is real valued. Alternatively, the existence of positive potential solitons can terminate when positive potential double layers occur.
Existence dimension of media-educational space
B. V. Bratanich
2014-03-01
Full Text Available The world media culture is the everyday existential context of selfidentity. Entry into the media culture turns and practice, and by the adequate development of the problem field of human existence. Education as a way to selfdetermine human ways and purposes of entry into the modern media culture in the field of communication and interaction with other people, mediated by electronic media. In the presence of global media space fundamental information plays a crucial role in socialization, is formed at the intersection of the education system and the electronic media, which gives grounds to determine exactly mediaeducational community primary medium of socialization in the age of online media. Media education environment creates more favorable conditions to educational activities has become a way of selfidentity, as it results of creative activity of the subject taken by others as taking it himself, his personality. Its major advantage as space being is to provide the maximum activity of the individual in determining the trajectory of development. A common basis for resolving the risks socialization and being the person in the media education area are the values and goals of selfdevelopment, formulated within postmodern education.
Global marketing and globalization miths
2012-01-01
Global marketing and advertising: understanding cultural paradoxes, de Marieke de Mooij, 3rd ed. Thousand Oaks, CA. Sage Publications, 2010, 322p. Global marketing and advertising: understanding cultural paradoxes, de Marieke de Mooij, 3rd ed. Thousand Oaks, CA. Sage Publications, 2010, 322p.
Global Content in Global Coursebooks
Mimoun Melliti
2013-10-01
Full Text Available This study aims at exploring the issue of “globality” in global coursebooks as manifested in investing features of connectedness, avoiding inappropriacy, and preserving inclusivity. To do this exploration, two research methods, content analysis and the questionnaire, were adopted. The content of an example of global coursebooks, Headway Intermediate (H/I, in addition to the perception of 251 of its users at Institute Bourguiba for Living Languages (IBLV were investigated. The results obtained revealed that “globality,” in terms of connectedness, inappropriacy, and inclusivity is partial in H/I as learners’ perceptions of it do not map with the content in the coursebook. This study raises questions about the suitability of global coursebooks to globally diverse learners and reveals the necessity of taking measures in the direction of localizing the content of English as a foreign language (EFL coursebooks.
Is 21st-century Rome a global city? Is it part of Europe's core or periphery? This volume examines the “real city” beyond Rome's historical center, exploring the diversity and challenges of life in neighborhoods affected by immigration, neoliberalism, formal urban planning, and grassroots social...... movements. The contributors engage with themes of contemporary urban studies–the global city, the self-made city, alternative modernities, capital cities and nations, urban change from below, and sustainability. Global Rome serves as a provocative introduction to the Eternal City and makes an original...
Harrington, Brooke
2015-01-01
This study links theories of relationality and institutional change to deepen understanding of professionals’ role in globalization. In previous institutional research, it has been conventional to treat professionals as agents of firms or transnational organizations, and institutional change...... environment. It also broadens the model of agency to include invention and improvisation by individual professionals, as a counterpart to collective strategic action. The argument is based on data from a 16-nation study exploring the emergence of a particular ‘globalized localism’: the transformation...... to specify a new, more detailed model of the ways local practices and ideas develop into global institutions....
Is 21st-century Rome a global city? Is it part of Europe's core or periphery? This volume examines the “real city” beyond Rome's historical center, exploring the diversity and challenges of life in neighborhoods affected by immigration, neoliberalism, formal urban planning, and grassroots social...... movements. The contributors engage with themes of contemporary urban studies–the global city, the self-made city, alternative modernities, capital cities and nations, urban change from below, and sustainability. Global Rome serves as a provocative introduction to the Eternal City and makes an original...
Do cement nanoparticles exist in space ?
Bilalbegovic, G; Mohacek-Grosev, V
2014-01-01
The calcium-silicate-hydrate is used to model properties of cement on Earth. We study cementitious nanoparticles and propose these structures as components of cosmic dust grains. Quantum density functional theory methods are applied for the calculation of infrared spectra of Ca4Si4O14H4, Ca6Si3O13H2, and Ca12Si6O26H4 clusters. We find bands distributed over the near, mid and far-infrared region. A specific calcium-silicate-hydrate spectral feature at 14 microns, together with the bands at 10 and 18 microns which exist for other silicates as well, could be used for a detection of cosmic cement. We compare calculated bands with the 14 microns features in the spectra of HD 45677, HD 44179, and IRC+10420 which were observed by Infrared Space Observatory and classified as remaining. High abundance of oxygen atoms in cementitious nanoparticles could partially explain observed depletion of this element from the interstellar medium into dust grains.
Yao Lei; Wang Wenjun
2008-01-01
This is a continuation of the article (Comm. Partial Differential Equations 26 (2001) 965). In this article, the authors consider the one-dimensional compressible isentropic Navier-Stokes equations with gravitational force, fixed boundary condition, a general pressure and the density-dependent viscosity coefficient when the viscous gas con-nects to vacuum state with a jump in density. Precisely, the viscosity coefficient u is proportional to pθ and 0 < θ < 1/2, where p is the density, and the pressure P =P(p) is a general pressure. The global existence and the uniqueness of weak solution are proved.
Borrás, Susana; Haakonsson, Stine Jessen
Lead firms are increasingly reorganizing their innovation activities into global innovation networks. Such reorganization has potentially major impact on their existing home-based innovation networks. Based on 31 interviews in four case studies of lead firms in the Danish food industry, the paper...... analyzes the dynamics of five key features of home-based innovation networks: 1) size of the national networks, 2) type of organization, 3) content of collaboration within the network, 4) concurrent globalization of organizations in the network, and 5) degree of formalization of network interactions....... The dynamics are generally differentiated according to the type of lead firm strategy, i.e. knowledge augmenting or knowledge exploiting. The qualitative and exploratory findings point towards some effects on national innovation networks. Hence, the paper concludes by hypothesizing that the globalization...
While "one world government" is not on the cards, the globalization of political life has progressed significantly over the last decades. Rather than adding on to existing theoretical frameworks such as the realist picture of international anarchy or the English School's "international society......", this volume starts out from the idea of the world as one interconnected political system and explores ways and perspectives to analyze it as such. The contributors examine central aspects of this emerging global polity such as the role of law, of networks and of civil society. They discuss key theoretical...... and meta-theoretical questions on how to analyze and theorize the global polity, what drives it forward, and whether it can be democratized....
Sørensen, Olav Jull
2016-01-01
The concept of Global Mindset (GM) – the way to think about the global reality – is on the agenda of multinational companies concomitant with the increase in global complexity, uncertainty and diversity. In spite of a number of studies, the concept is still fluid and far from a managerial...... way of thinking about the global business reality. The other extreme is a GM as an organizational capability and process with a GM in a continuous state of becoming – and thus in a continuously alignment with a dynamic context. In addition, we argue for what we call “situational capabilities”, i.......e. the capability to sense (quickly), reflect (constructively) and act purposefully (for mutual benefit). A case on an MNC is used at the end to show the organizational manifestations of a GM....
Andersen, Torben Juul
." - Steen Parsholt, Chairman and CEO, Aon Nordic Region. "Andersen has done a wonderful job of developing a comprehensive text that deals with risk management in global markets. I would recommend this book to any student or businessman who has a need to better understand the risks and risk management...... management practice. Of particular note is the global and integrated approach chosen in this book which should be of special interest to aspiring managers active in global and international markets." - Dr Jean-Pierre Zigrand, Lecturer in Finance, London School of Economics, UK. More than 90 per cent...... management situations. Its key features include: derivatives are introduced in a global market perspective; describes major derivative pricing models for practical use, extending these principles to valuation of real options; practical applications of derivative instruments are richly illustrated...
Barakat, Livia L.; Lorenz, Melanie P.; Ramsey, Jase R.
2016-01-01
urpose: – The purpose of this paper is to examine the effect of cultural intelligence (CQ) on the job performance of global managers. Design/methodology/approach: – In total, 332 global managers were surveyed from multinational companies operating in Brazil. The mediating effect of job satisfaction...... was tested on the CQ-job performance relationship. Findings: – The findings suggest that job satisfaction transmits the effect of CQ to job performance, such that global managers high in CQ exhibit more job satisfaction in an international setting, and therefore perform better at their jobs. Practical...... implications: – Results imply that global managers should increase their CQ in order to improve their job satisfaction and ultimately perform better in an international context. Originality/value: – The authors make three primary contributions to the international business literature. First, the authors...
Milwertz, Cecilia Nathansen; Cai, Yiping
2017-01-01
Both the People’s Republic of China (PRC) and Nordic countries (Sweden, Iceland, Denmark, Norway and Finland) view gender equality as a social justice issue and are politically committed towards achieving gender equality nationally and internationally. Since China has taken a proactive position o...... on globalization and global governance, gender equality is possibly an area that China may wish to explore in collaboration with the Nordic countries....
Existence and Stability of Gauged Non-Topological Solitons
Lee, Chul H.; Yoon, Seung Un
Classical non-topological soliton configurations are considered in a theory with a local U(1) symmetry. Their existence, stability against dispersion into free particles are studied numerically. As in the case of Friedberg, Lee, and Sirlin with a global U(1) symmetry, also in this case there are two critical charges; Qc for the existence and Qs for the stability of the non-topological soliton configurations. Our numerical results show that the magnitudes of both Qc and Qs increase as the magnitude of the gauge coupling constant e is increased with the other parameters kept at fixed values.
Existence of homoclinic connections in continuous piecewise linear systems.
Carmona, Victoriano; Fernández-Sánchez, Fernando; García-Medina, Elisabeth; Teruel, Antonio E
2010-03-01
Numerical methods are often used to put in evidence the existence of global connections in differential systems. The principal reason is that the corresponding analytical proofs are usually very complicated. In this work we give an analytical proof of the existence of a pair of homoclinic connections in a continuous piecewise linear system, which can be considered to be a version of the widely studied Michelson system. Although the computations developed in this proof are specific to the system, the techniques can be extended to other piecewise linear systems.
Barakat, Livia L.; Lorenz, Melanie P.; Ramsey, Jase R.
2016-01-01
Purpose: – The purpose of this paper is to examine the effect of cultural intelligence (CQ) on the job performance of global managers. Design/methodology/approach: – In total, 332 global managers were surveyed from multinational companies operating in Brazil. The mediating effect of job satisfact...... behavior literature, it is not often explicitly associated with global managers that are working in cross-cultural settings. Finally, the authors posit that job satisfaction mediates the relationship between CQ and job performance.......Purpose: – The purpose of this paper is to examine the effect of cultural intelligence (CQ) on the job performance of global managers. Design/methodology/approach: – In total, 332 global managers were surveyed from multinational companies operating in Brazil. The mediating effect of job...... satisfaction was tested on the CQ-job performance relationship. Findings: – The findings suggest that job satisfaction transmits the effect of CQ to job performance, such that global managers high in CQ exhibit more job satisfaction in an international setting, and therefore perform better at their jobs...
Hulme, M
1998-01-01
Global warming-like deforestation, the ozone hole and the loss of species- has become one of the late 20the century icons of global environmental damage. The threat, is not the reality, of such a global climate change has motivated governments. businesses and environmental organisations, to take serious action ot try and achieve serious control of the future climate. This culminated last December in Kyoto in the agreement for legally-binding climate protocol. In this series of three lectures I will provide a perspective on the phenomenon of global warming that accepts the scientific basis for our concern, but one that also recognises the dynamic interaction between climate and society that has always exited The future will be no different. The challenge of global warning is not to pretend it is not happening (as with some pressure groups), nor to pretend it threatens global civilisation (as with other pressure groups), and it is not even a challenge to try and stop it from happening-we are too far down the ro...
Can increasing albedo of existing ship wakes reduce climate change?
Crook, Julia A.; Jackson, Lawrence S.; Forster, Piers M.
2016-02-01
Solar radiation management schemes could potentially alleviate the impacts of global warming. One such scheme could be to brighten the surface of the ocean by increasing the albedo and areal extent of bubbles in the wakes of existing shipping. Here we show that ship wake bubble lifetimes would need to be extended from minutes to days, requiring the addition of surfactant, for ship wake area to be increased enough to have a significant forcing. We use a global climate model to simulate brightening the wakes of existing shipping by increasing wake albedo by 0.2 and increasing wake lifetime by ×1440. This yields a global mean radiative forcing of -0.9 ± 0.6 Wm-2 (-1.8 ± 0.9 Wm-2 in the Northern Hemisphere) and a 0.5°C reduction of global mean surface temperature with greater cooling over land and in the Northern Hemisphere, partially offsetting greenhouse gas warming. Tropical precipitation shifts southward but remains within current variability. The hemispheric forcing asymmetry of this scheme is due to the asymmetry in the distribution of existing shipping. If wake lifetime could reach ~3 months, the global mean radiative forcing could potentially reach -3 Wm-2. Increasing wake area through increasing bubble lifetime could result in a greater temperature reduction, but regional precipitation would likely deviate further from current climatology as suggested by results from our uniform ocean albedo simulation. Alternatively, additional ships specifically for the purpose of geoengineering could be used to produce a larger and more hemispherically symmetrical forcing.
Possible existence of wormholes in the central regions of halos
Rahaman, Farook, E-mail: rahaman@iucaa.ernet.in [Department of Mathematics, Jadavpur University, Kolkata 700032, West Bengal (India); Salucci, P., E-mail: salucci@sissa.it [SISSA, International School for Advanced Studies, Via Bonomea 265, 34136, Trieste (Italy); INFN, Sezione di Trieste, Via Valerio 2, 34127, Trieste (Italy); Kuhfittig, P.K.F., E-mail: kuhfitti@msoe.edu [Department of Mathematics, Milwaukee School of Engineering, Milwaukee, WI 53202-3109 (United States); Ray, Saibal, E-mail: saibal@iucaa.ernet.in [Department of Physics, Government College of Engineering and Ceramic Technology, Kolkata 700010, West Bengal (India); Rahaman, Mosiur, E-mail: mosiurju@gmail.com [Department of Mathematics, Meghnad Saha Institute of Technology, Kolkata 700150 (India)
2014-11-15
An earlier study (Rahaman, et al., 2014 and Kuhfittig, 2014) has demonstrated the possible existence of wormholes in the outer regions of the galactic halo, based on the Navarro–Frenk–White (NFW) density profile. This paper uses the Universal Rotation Curve (URC) dark matter model to obtain analogous results for the central parts of the halo. This result is an important compliment to the earlier result, thereby confirming the possible existence of wormholes in most of the spiral galaxies. - Highlights: • Earlier we showed possible existence of wormholes in the outer regions of halo. • We obtain here analogous results for the central parts of the galactic halo. • Our result is an important compliment to the earlier result. • This confirms possible existence of wormholes in most of the spiral galaxies.
Existence and uniqueness in anisotropic conductivity reconstruction with Faraday's law
Lee, Min-Gi
2015-03-18
We show that three sets of internal current densities are the right amount of data that give the existence and the uniqueness at the same time in reconstructing an anisotropic conductivity in two space dimensions. The curl free equation of Faraday’s law is taken instead of the usual divergence free equation of the electrical impedance to- mography. Boundary conditions related to given current densities are introduced which complete a well determined problem for conductivity reconstruction together with Fara- day’s law.
Existence of Weak Solutions for the Incompressible Euler Equations
Wiedemann, Emil
2011-01-01
Using a recent result of C. De Lellis and L. Sz\\'{e}kelyhidi Jr. we show that, in the case of periodic boundary conditions and for dimension greater or equal 2, there exist infinitely many global weak solutions to the incompressible Euler equations with initial data $v_0$, where $v_0$ may be any solenoidal $L^2$-vectorfield. In addition, the energy of these solutions is bounded in time.
Existence of a coupled system of fractional differential equations
Ibrahim, Rabha W. [Multimedia unit, Department of Computer System and Technology Faculty of Computer Science & IT, University of Malaya, 50603 Kuala Lumpur (Malaysia); Siri, Zailan [Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia)
2015-10-22
We manage the existence and uniqueness of a fractional coupled system containing Schrödinger equations. Such a system appears in quantum mechanics. We confirm that the fractional system under consideration admits a global solution in appropriate functional spaces. The solution is shown to be unique. The method is based on analytic technique of the fixed point theory. The fractional differential operator is considered from the virtue of the Riemann-Liouville differential operator.
Optimizing Existing Multistory Building Designs towards Net-Zero Energy
Mohammad Y. AbuGrain; Halil Z. Alibaba
2017-01-01
Recent global developments in awareness and concerns about environmental problems have led to reconsidering built environment approaches and construction techniques. One of the alternatives is the principle of low/zero-energy buildings. This study investigates the potentials of energy savings in an existing multi-story building in the Mediterranean region in order to achieve net-zero energy as a solution to increasing fossil fuel prices. The Colored building at the Faculty of Architecture, Ea...
The existence of Hadley convective regimes of atmospheric motion
Dutton, J. A.; Kloeden, P. E.
1983-01-01
The solutions of the equations describing deep global convection on a rotating planet are discussed. The existence of generalized steady axisymmetric solutions is established. It is then shown that these are classical solutions when the heat source is sufficiently smooth. The solutions are shown to be unique when the heating is sufficiently weak and asymptotically stable when the shear is sufficiently small. Finally, the application of these results to earth's atmosphere is discussed, with eddy viscosity replacing molecular viscosity.
Jedidi, Abdesslem; Li, Rui; Fornasiero, Paolo; Cavallo, Luigi; Carbonniere, Philippe
2015-12-03
Vibrational fingerprints of small Pt(n)P(2n) (n = 1-5) clusters were computed from their low-lying structures located from a global exploration of their DFT potential energy surfaces with the GSAM code. Five DFT methods were assessed from the CCSD(T) wavenumbers of PtP2 species and CCSD relative energies of Pt2P4 structures. The eight first Pt(n)P(2n) isomers found are reported. The vibrational computations reveal (i) the absence of clear signatures made by overtone or combination bands due to very weak mechanical and electrical anharmonicities and (ii) some significant and recurrent vibrational fingerprints in correlation with the different PP bonding situations in the Pt(n)P(2n) structures.
10 CFR 4.127 - Existing facilities.
2010-01-01
... 10 Energy 1 2010-01-01 2010-01-01 false Existing facilities. 4.127 Section 4.127 Energy NUCLEAR... 1973, as Amended Discriminatory Practices § 4.127 Existing facilities. (a) Accessibility. A recipient... make each of its existing facilities or every part of an existing facility accessible to and usable by...
28 CFR 41.57 - Existing facilities.
2010-07-01
... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Existing facilities. 41.57 Section 41.57... Practices Program Accessibility § 41.57 Existing facilities. (a) A recipient shall operate each program or... existing facilities or every part of an existing facility accessible to and usable by handicapped...
2007-01-01
In this paper,we study the one-dimensional motion of viscous gas with a general pres- sure law and a general density-dependent viscosity coefficient when the initial density connects to the vacuum state with a jump.We prove the global existence and the uniqueness of weak solutions to the compressible Navier-Stokes equations by using the line method.For this,some new a priori estimates are obtained to take care of the general viscosity coefficientμ(ρ)instead ofρ~θ.
Mei-man SUN; Chang-jiang ZHU
2007-01-01
In this paper, we study the one-dimensional motion of viscous gas with a general pressure law and a general density-dependent viscosity coefficient when the initial density connects to the vacuum state with a jump. We prove the global existence and the uniqueness of weak solutions to the compressible Navier-Stokes equations by using the line method. For this, some new a priori estimates are obtained to take care of the general viscosity coefficient μ(ρ) instead of ρθ.
Superfluid density in the d-density-wave scenario.
Wang, Q H; Han, J H; Lee, D H
2001-08-13
Recently Chakravarty, Laughlin, Morr, and Nayak [Phys. Rev. B 62, 4880 (2000)] made an interesting proposal that the cuprate superconductors possess a hidden " d-density-wave" (DDW) order. We study the implication of this proposal for the superfluid density rho(s). We find that it predicts a temperature gradient [d rho(s)/dT](T = 0) that is strongly doping dependent near the critical doping at which the superconducting gap vanishes. This demonstrates that the DDW scenario is inconsistent with existing well-established experimental data.
Global Theory to Understand Toroidal Drift Waves in Steep Gradient
Xie, Hua-Sheng
2016-01-01
Toroidal drift waves with unconventional mode structures and non-ground eigenstates, which differ from typical ballooning structure mode, are found to be important recently by large scale global gyrokinetic simulations and especially become dominant at strong gradient edge plasmas [cf., Xie and Xiao, Phys. Plasmas, 22, 090703 (2015)]. The global stability and mode structures of drift wave in this steep edge density and temperature gradients are examined by both direct numerical solutions of a model two-dimensional eigen equation and analytical theory employing WKB-ballooning approach. Theory agrees with numerical solutions quite well. Our results indicate that (i) non-ground eigenstates and unconventional mode structures generally exist and can be roughly described by two parameters `quantum number' $l$ and ballooning angle $\\vartheta_k$, (ii) local model can overestimate the growth rate largely, say, $>50\\%$, and (iii) the narrow steep equilibrium profile leads to twisting (triangle-like) radial mode structu...
Lindberg Christensen, Lars; Russo, P.
2009-05-01
IYA2009 is a global collaboration between almost 140 nations and more than 50 international organisations sharing the same vision. Besides the common brand, mission, vision and goals, IAU established eleven cornerstones programmes to support the different IYA2009 stakeholder to organize events, activities under a common umbrella. These are global activities centred on specific themes and are aligned with IYA2009's main goals. Whether it is the support and promotion of women in astronomy, the preservation of dark-sky sites around the world or educating and explaining the workings of the Universe to millions, the eleven Cornerstones are key elements in the success of IYA2009. However, the process of implementing global projects across cultural boundaries is challenging and needs central coordination to preserve the pre-established goals. During this talk we will examine the ups and downs of coordinating such a project and present an overview of the principal achievements for the Cornerstones so far.
Niño-Zarazúa, Miguel; Roope, Laurence; Tarp, Finn
2016-01-01
This paper measures trends in global interpersonal inequality during 1975–2010 using data from the most recent version of the World Income Inequality Database (WIID). The picture that emerges using ‘absolute,’ and even ‘centrist’ measures of inequality, is very different from the results obtained...... using standard ‘relative’ inequality measures such as the Gini coefficient or Coefficient of Variation. Relative global inequality has declined substantially over the decades. In contrast, ‘absolute’ inequality, as captured by the Standard Deviation and Absolute Gini, has increased considerably...... and unabated. Like these ‘absolute’ measures, our ‘centrist’ inequality indicators, the Krtscha measure and an intermediate Gini, also register a pronounced increase in global inequality, albeit, in the case of the latter, with a decline during 2005 to 2010. A critical question posed by our findings is whether...
Prof. Ph.D. Ion Bucur
2007-05-01
Full Text Available Finding the anachronisms and the failures of the present globalization, as well as the vitiated system of world-wide government, has stimulated the debates regarding the identification of a more equitable form of globalization to favor the acceleration of the economic increase and the reduction of poverty.The deficiency of the present international economic institutions, especially the lack of transparency and democratic responsibility, claims back with acuteness the reformation of the architecture of the international institutional system and the promotion of those economical policies which must ensure the stability world-wide economy and the amelioration of the international equity.
Cheraghi, Maryam; Schøtt, Thomas
2016-01-01
A firm may be conceived global, in the sense that, before its birth, the founding entrepreneur has a transnational network of advisors which provides an embedding for organising the upstart that may include assembling resources and marketing abroad. The purpose is to account for the entrepreneurs...... the intending, starting and operating phases, fairly constantly with only small fluctuations. The firm is conceived global in terms of the entrepreneur's transnational networking already in the pre-birth phase, when the entrepreneur is intending to start the firm. These phase effects hardly depend on attributes...
Fejerskov, Adam Moe; Rasmussen, Christel
2016-01-01
During the past decade, academic attention to the role of private foundations in international development cooperation has greatly intensified. The largest foundations have increased their global giving and moved towards strategic social impact, but we do not know if such processes have also...... occurred at a more micro level. This article explores this issue by studying the international activities of Danish foundations. It finds that grant-making on global issues is increasing, and that several foundations have undergone transformations in their approach to grantmaking, making them surprisingly...
The density minimum at the Earth's magnetic equator
1992-01-01
Journal of Geophysical Research,Volume 97, pp. 1135-1150 Observations of the density structure in the plasmapause region reveal the existence of a local minimum in the total electron density at the magnetic equator.
Noundjeu, P
2003-01-01
Using the iterative Scheme we prove the local existence and uniqueness of solutions of the spherically symmetric Einstein-Vlasov-Maxwell system with small initial data. We prove a continuation criterion to global in-time solutions.
Park Jong Yeoul
2007-01-01
Full Text Available We study the existence of global weak solutions for a hyperbolic differential inclusion with a source term, and then investigate the asymptotic stability of the solutions by using Nakao lemma.
EXISTENCE AND UNIQUENESS OF PERIODIC SOLUTIONS FOR GRADIENT SYSTEMS IN FINITE DIMENSIONAL SPACES
Sahbi BOUSSANDEL
2016-01-01
This paper deals with an abstract periodic gradient system in which the gradient is taken with respect to a variable metric. We obtain an existence and uniqueness result via the application of a global inverse theorem.
van der Linden, M.
2009-01-01
The recent growth of the working classes in various parts of the Global South (or what was called the Tricontinent of Africa, Asia, and Latin America some years ago) has important consequences for labor historians. For a very long time labor history was mainly based in the North Atlantic region,
M.J. Mol; R.J.M. van Tulder (Rob); P.R. Beije (Paul)
2002-01-01
textabstractSince the early 1990s international - or even global - outsourcing of intermediate products from suppliers has been propagated as a key means to improve the performance of firms. It is argued that becoming more lean and internationally focused is beneficial for the buyer as
2012-01-01
Molycorp Announces Successful Close of Neo Materials Acquisition Molycorp, Inc. announced on 11 June 2012 that its acquisition of Canadian-based Neo Material Technologies Inc. has officially closed, creating a global rare earth leader with a combination of a world-class rare earth resource, ultra-high-purity rare earth processing capabilities, and full ＇mine-to-magnetics＇ vertical integration.
Wilson, Erin; Steger, Manfred; Siracusa, Joseph; Battersby, Paul
2014-01-01
The pursuit of a global order founded on universal rules extends beyond economics into the normative spheres of law, politics and justice. Justice globalists claim universal principles applicable to all societies irrespective of religion or ideology. This view privileges human rights, democracy and
Rosenstand, Claus A. Foss
2007-01-01
- idet min lillebror er blandt de anholdte; og mine forældre derfor skulle være blandt de skyldige. Hvilket har fået mig til at fare i blækhuset, med en alternativ forklaringsmodel, der ikke handler om skyld. Kulturen omkring Ungdomshuset er globalt orienteret, og derfor meget sensible overfor global...... forandringer. Den globale orientering kommer blandt andet til udtryk i det relativt store internationale netværk, som bakker de unge op i deres protester - enten ved tilstedeværelse i København eller andre sympatiaktioner. Siden den 11. september, 2001, er globale realiteter blevet eksponeret i massemedierne...... også sig selv og sin omverden igennem en global optik. Ungdommen af i dag er som børn vokset op i et samfund og dannelseskultur, der ikke har været globalt orienteret, hvor demokratiske værdier som frihed, lighed, menneskerettigheder her hersket i det socialdemokratiske projekt om sammenhængskraft. Og...
van Bottenburg, Maarten
2001-01-01
Why is soccer the sport of choice in South America, while baseball has soared to popularity in the Carribean? How did cricket become India's national sport, while China is a stronghold of table tennis? In Global Games, Maarten van Bottenburg asserts that it is the 'hidden competition' of social and
Wilson, Erin; Steger, Manfred; Siracusa, Joseph; Battersby, Paul
2014-01-01
The pursuit of a global order founded on universal rules extends beyond economics into the normative spheres of law, politics and justice. Justice globalists claim universal principles applicable to all societies irrespective of religion or ideology. This view privileges human rights, democracy and
Brewer, Thomas L.; Boyd, Gavin
An argument that globalization is an ungoverned integration process in which US firms are agents of structural change. It describes the benefits and costs (for example, generating pressure for protection of US home markets), and reviews the expansion of interdependencies between the US and others....
Rosenstand, Claus A. Foss
2007-01-01
- idet min lillebror er blandt de anholdte; og mine forældre derfor skulle være blandt de skyldige. Hvilket har fået mig til at fare i blækhuset, med en alternativ forklaringsmodel, der ikke handler om skyld. Kulturen omkring Ungdomshuset er globalt orienteret, og derfor meget sensible overfor global...... forandringer. Den globale orientering kommer blandt andet til udtryk i det relativt store internationale netværk, som bakker de unge op i deres protester - enten ved tilstedeværelse i København eller andre sympatiaktioner. Siden den 11. september, 2001, er globale realiteter blevet eksponeret i massemedierne...... også sig selv og sin omverden igennem en global optik. Ungdommen af i dag er som børn vokset op i et samfund og dannelseskultur, der ikke har været globalt orienteret, hvor demokratiske værdier som frihed, lighed, menneskerettigheder her hersket i det socialdemokratiske projekt om sammenhængskraft. Og...
Wallensteen, P.; Galtung, J.; Portales, C.
1985-01-01
This book contains 10 chapters. Some of the titles are: Military Formations and Social Formations: A Structural Analysis; Global Conflict Formations: Present Developments and Future Directions; War and the Power of Warmakers in Western Europe and Elsewhere, 1600-1980; and The Urban Type of Society and International War.
van Bottenburg, Maarten
2001-01-01
Why is soccer the sport of choice in South America, while baseball has soared to popularity in the Carribean? How did cricket become India's national sport, while China is a stronghold of table tennis? In Global Games, Maarten van Bottenburg asserts that it is the 'hidden competition' of social and
Balažić Milan
2006-01-01
Full Text Available Since the fall of the Berlin wall, the process of globalization has been understood as a necessary fate. The myth of the almightiness of the market economy, liberalization and deregulation is revitalized. Before us, there is a phenomenon Lacan’s discourse of University, which in 20 century was firstly given as a Stalinist discourse and today is given as a neo-liberal discourse of globalization. From underneath og a seeming objectivity, a Master insists-either the Party and the Capital. Just as the utopia of the world proletarian revolution has fallen apart, the utopia of globalize capitalism and liberal democracy is also falling apart. The 9/11 event is opening opportunities for a construction of the field of social and political, out of the contour of the status quo. The coordinates of the possibility has changed and if we take the non-existence of the grand Autre on ourselves, then the contingence interference in the existent socio-symbolic order is possible.
Affine density in wavelet analysis
Kutyniok, Gitta
2007-01-01
In wavelet analysis, irregular wavelet frames have recently come to the forefront of current research due to questions concerning the robustness and stability of wavelet algorithms. A major difficulty in the study of these systems is the highly sensitive interplay between geometric properties of a sequence of time-scale indices and frame properties of the associated wavelet systems. This volume provides the first thorough and comprehensive treatment of irregular wavelet frames by introducing and employing a new notion of affine density as a highly effective tool for examining the geometry of sequences of time-scale indices. Many of the results are new and published for the first time. Topics include: qualitative and quantitative density conditions for existence of irregular wavelet frames, non-existence of irregular co-affine frames, the Nyquist phenomenon for wavelet systems, and approximation properties of irregular wavelet frames.
10 CFR 611.206 - Existing facilities.
2010-01-01
... 10 Energy 4 2010-01-01 2010-01-01 false Existing facilities. 611.206 Section 611.206 Energy... PROGRAM Facility/Funding Awards § 611.206 Existing facilities. The Secretary shall, in making awards to those manufacturers that have existing facilities, give priority to those facilities that are oldest or...
45 CFR 1170.32 - Existing facilities.
2010-10-01
... 45 Public Welfare 3 2010-10-01 2010-10-01 false Existing facilities. 1170.32 Section 1170.32... ASSISTED PROGRAMS OR ACTIVITIES Accessibility § 1170.32 Existing facilities. (a) Accessibility. A recipient... require a recipient to make each of its existing facilities or every part of a facility accessible to and...
45 CFR 1151.22 - Existing facilities.
2010-10-01
... 45 Public Welfare 3 2010-10-01 2010-10-01 false Existing facilities. 1151.22 Section 1151.22... Prohibited Accessibility § 1151.22 Existing facilities. (a) A recipient shall operate each program or... make each of its existing facilities or every part of a facility accessible to and usable by...
14 CFR 1251.301 - Existing facilities.
2010-01-01
... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Existing facilities. 1251.301 Section 1251... HANDICAP Accessibility § 1251.301 Existing facilities. (a) Accessibility. A recipient shall operate each... existing facilities or every part of a facility accessible to and usable by handicapped persons. (b...
45 CFR 605.22 - Existing facilities.
2010-10-01
... 45 Public Welfare 3 2010-10-01 2010-10-01 false Existing facilities. 605.22 Section 605.22 Public... Accessibility § 605.22 Existing facilities. (a) Accessibility. A recipient shall operate each program or... existing facilities or every part of a facility accessible to and usable by qualified handicapped persons...
34 CFR 104.22 - Existing facilities.
2010-07-01
... 34 Education 1 2010-07-01 2010-07-01 false Existing facilities. 104.22 Section 104.22 Education... Accessibility § 104.22 Existing facilities. (a) Accessibility. A recipient shall operate its program or activity.... This paragraph does not require a recipient to make each of its existing facilities or every part of a...
28 CFR 42.521 - Existing facilities.
2010-07-01
... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Existing facilities. 42.521 Section 42...-Implementation of Section 504 of the Rehabilitation Act of 1973 Accessibility § 42.521 Existing facilities. (a... section does not require a recipient to make each of its existing facilities or every part of a...
45 CFR 1232.14 - Existing facilities.
2010-10-01
... 45 Public Welfare 4 2010-10-01 2010-10-01 false Existing facilities. 1232.14 Section 1232.14... ASSISTANCE Accessibility § 1232.14 Existing facilities. (a) A recipient shall operate each program or... existing facilities or every part of a facility accessible to and usable by handicapped persons. (b)...
28 CFR 35.150 - Existing facilities.
2010-07-01
... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Existing facilities. 35.150 Section 35... STATE AND LOCAL GOVERNMENT SERVICES Program Accessibility § 35.150 Existing facilities. (a) General. A... paragraph does not— (1) Necessarily require a public entity to make each of its existing...
Research on Inequalities Exists in the Workplace
布乃鹏; 樊晶晶; 刘淑华
2013-01-01
The is ue of inequalities exists in the workplace has been widely debated in our community recently. And then this essay wil argue inequalities exist in the workplace, in terms of ethnic, gender, and disability. This es ay would of er four perspectives about the view inequalities exist in the workplace and discuss the response from the state, employers and unions.
Climate change: an amplifier of existing health risks in developing countries.
Huynen, Maud; Martens, Pim
2013-01-01
Global warming is perceived as one of the biggest global health risks of the twenty-first century and a threat to the achievement of sustainable (economic) development; especially in developing countries, climate change is believed to further exacerbate existing vulnerability to disease and food
Existence conditions for unknown input functional observers
Fernando, T.; MacDougall, S.; Sreeram, V.; Trinh, H.
2013-01-01
This article presents necessary and sufficient conditions for the existence and design of an unknown input Functional observer. The existence of the observer can be verified by computing a nullspace of a known matrix and testing some matrix rank conditions. The existence of the observer does not require the satisfaction of the observer matching condition (i.e. Equation (16) in Hou and Muller 1992, 'Design of Observers for Linear Systems with Unknown Inputs', IEEE Transactions on Automatic Control, 37, 871-875), is not limited to estimating scalar functionals and allows for arbitrary pole placement. The proposed observer always exists when a state observer exists for the unknown input system, and furthermore, the proposed observer can exist even in some instances when an unknown input state observer does not exist.
A fully traits-based approach to modeling global vegetation distribution.
van Bodegom, Peter M; Douma, Jacob C; Verheijen, Lieneke M
2014-09-23
Dynamic Global Vegetation Models (DGVMs) are indispensable for our understanding of climate change impacts. The application of traits in DGVMs is increasingly refined. However, a comprehensive analysis of the direct impacts of trait variation on global vegetation distribution does not yet exist. Here, we present such analysis as proof of principle. We run regressions of trait observations for leaf mass per area, stem-specific density, and seed mass from a global database against multiple environmental drivers, making use of findings of global trait convergence. This analysis explained up to 52% of the global variation of traits. Global trait maps, generated by coupling the regression equations to gridded soil and climate maps, showed up to orders of magnitude variation in trait values. Subsequently, nine vegetation types were characterized by the trait combinations that they possess using Gaussian mixture density functions. The trait maps were input to these functions to determine global occurrence probabilities for each vegetation type. We prepared vegetation maps, assuming that the most probable (and thus, most suited) vegetation type at each location will be realized. This fully traits-based vegetation map predicted 42% of the observed vegetation distribution correctly. Our results indicate that a major proportion of the predictive ability of DGVMs with respect to vegetation distribution can be attained by three traits alone if traits like stem-specific density and seed mass are included. We envision that our traits-based approach, our observation-driven trait maps, and our vegetation maps may inspire a new generation of powerful traits-based DGVMs.
Neuroscience and Global Learning.
Ruscio, Michael G; Korey, Chris; Birck, Anette
2015-01-01
Traditional study abroad experiences take a variety of forms with most incorporating extensive cultural emersion and a focus on global learning skills. Here we ask the question: Can this type of experience co-exist with a quality scientific experience and continued progression through a typically rigorous undergraduate neuroscience curriculum? What are the potential costs and benefits of this approach? How do we increase student awareness of study abroad opportunities and inspire them to participate? We outline programs that have done this with some success and point out ways to cultivate this approach for future programs. These programs represent a variety of approaches in both their duration and role in a given curriculum. We discuss a one-week first year seminar program in Berlin, a summer study abroad course in Munich and Berlin, semester experiences and other options offered through the Danish Institute for Study Abroad in Copenhagen. Each of these experiences offers opportunities for interfacing global learning with neuroscience.
Global solutions for the two-component Camassa-Holm system
Grunert, K; Raynaud, X
2011-01-01
We prove existence of a global conservative solution of the Cauchy problem for the two-component Camassa-Holm (2CH) system on the line, allowing for nonvanishing and distinct asymptotics at plus and minus infinity. The solution is proven to be smooth as long as the density is bounded away from zero. Furthermore, we show that by taking the limit of vanishing density in the 2CH system, we obtain the global conservative solution of the (scalar) Camassa-Holm equation, which provides a novel way to define and obtain these solutions. Finally, it is shown that while solutions of the 2CH system have infinite speed of propagation, singularities travel with finite speed.
Laboratory Density Functionals
Giraud, B. G.
2007-01-01
We compare several definitions of the density of a self-bound system, such as a nucleus, in relation with its center-of-mass zero-point motion. A trivial deconvolution relates the internal density to the density defined in the laboratory frame. This result is useful for the practical definition of density functionals.
Laboratory Density Functionals
Giraud, B G
2007-01-01
We compare several definitions of the density of a self-bound system, such as a nucleus, in relation with its center-of-mass zero-point motion. A trivial deconvolution relates the internal density to the density defined in the laboratory frame. This result is useful for the practical definition of density functionals.
Education for a Culture of Peace and Co-Existence
Silvia Guetta
2016-07-01
Full Text Available Education is a key and fundamental tool required to achieve social change, especially regarding social cohesion and co-existence. Education affects the most critical issues facing humanity, including the proliferation of various forms of violence, environmental degradation, and annihilation of cultures. I argue that the impact of education is equal to that of economics, politics, and technological advances. Therefore, if we wish to see change, educational reform has to be designed to operate in a global-human context, empowering and allowing people to achieve their potential. It should instil in individuals and groups respect for others with whom they interact, in a global as well as local sense. The article draws on the theories of Edgar Morin, Reuven Feuerstein, and Jerome Bruner, and their contributions to the development of educational approaches that encourage a culture of responsible, participatory, and creative coexistence. .
Organizing for Global Sourcing
Bals, Lydia; Turkulainen, Virpi
Research on Purchasing Organization is dominated by studies on centralization versus decentralization. While global sourcing relates to the integrated activities of purchasing and other functions in line with the company’s strategic objectives and while it has been put forward that hybrid...... organizations are on the rise, the exact ways in which companies employ hybrid organizations in this context have not been studied in further detail. By presenting a multi-year case study from 2010 to 2013 at a pharmaceutical company, we elaborate on the existing knowledge regarding hybrid organizations...
Global Noise and Global Englishes
Alastair Pennycook
2013-09-01
Full Text Available Global Noise: Rap and Hip-Hop Outside the USA, alluding to Tricia Rose’s US rap-music book, Black Noise, aims to do much more than merely extend the reach of the study of rap and hip-hop beyond the USA, as its subtitle might suggest. While acknowledging the importance of the work of both Rose and Potter, this collection’s editor, Tony Mitchell, contests their respective views that rap and hip-hop are essentially expressions of African-American culture, and that all forms of rap and hip-hop derive from these origins. He argues that these forms have become ‘a vehicle for global youth affiliations and a tool for reworking local iden- tity all over the world’.
Global climate experiment; Globales Klimaexperiment
Quasching, V. [Deutsche Zentrum fuer Luft- und Raumfahrt e.V., Plataforma Solar de Almeria (Spain)
2003-07-01
Continued greenhouse gas emissions are part of one of our today's largest scientific experiments. Most scientists agree that anthropogenic influences are responsible for already observed climatic changes. Others demand further investigations and justify continued unlimited use of fossil energy sources. This paper describes generally accepted facts on greenhouse gas emissions and climatic change with focus on part and influence of the global energy industry. [German] Mit dem fortgesetzten Ausstoss von Treibhausgasen wird zurzeit ein globales naturwissenschaftliches Experiment betrieben. Viele Wissenschaftler sind sich einig, dass bereits beobachtete Klimaveraenderungen auf den Einfluss des Menschen zurueckzufuehren sind. Andere fordern hingegen weitere Untersuchungen und halten bis dahin eine weitere uneingeschraenkte Verwendung fossiler Energietraeger fuer gerechtfertigt. Dieser Beitrag fasst weitgehend anerkannte Fakten ueber Treibhausgasemissionen und Klimaveraenderungen zusammen und beschreibt die Rolle und den Einfluss der Energiewirtschaft.
2011-03-01
The study aims to report the baseline characteristics of the fully randomized AIM-HIGH study population. Residual risk persists despite aggressive low-density lipoprotein cholesterol (LDL-C) reduction in patients with atherosclerotic cardiovascular (CV) disease, many of whom have atherogenic dyslipidemia (low levels of high-density lipoprotein cholesterol (HDL-C), elevated triglycerides, and small dense LDL particles). All study participants had established CV disease and atherogenic dyslipidemia. Participants received simvastatin (or simvastatin plus ezetimibe) at a dose sufficient to maintain LDL-C at 40 - 80 mg/dL (1.03-2.07 mmol/L) and were randomized to receive extended-release niacin or matching placebo. The primary end point is time to the first occurrence of coronary heart disease death, nonfatal myocardial infarction, ischemic stroke, hospitalization for acute coronary syndrome or symptom-driven coronary or cerebral revascularization with average follow-up of 4.1 years. Between 2006 and 2010, 8,162 individuals signed consent to be screened, 4,275 began study drug run-in, and 3,414 were randomized to treatment. Mean age at entry was 64 ± 9 years, 85% were men, and 92% were white. As expected, risk factors were prevalent with 34% having diabetes; 71%, hypertension; and 81%, metabolic syndrome. Most participants had coronary artery disease (92%), whereas 11% had peripheral arterial disease; and 12%, cerebrovascular disease. Previous coronary revascularization occurred in 82%, and 54% reported a prior myocardial infarction. Among participants on a statin at entry (94%), mean baseline LDL-C was 71 mg/dL (1.84 mmol/L); mean HDL-C, 34.9 mg/dL (0.90 mmol/L); and median triglycerides, 161 mg/dL (1.82 mmol/L). AIM-HIGH enrolled a high-risk group of patients with established atherosclerotic CV disease and atherogenic dyslipidemia. This study should determine whether there is incremental clinical benefit of niacin in reducing cardiovascular events in patients who
The Existence of Smooth Densities for the Prediction, Filtering and Smoothing Problems
1990-12-20
d’une equation differentielle stochastique avec semi-martingale directrice discontinue, Sem. dc Probabilit~s XIX. Lecture notes in Math. 1123...Proceedings of Internatiional Coinference. Kyoto. 1976 Wiley. 1978, 195-263. (1l] 1P A Meyer, Hlot d’une equation differentielle stochaistiquc...smoothing and, prediction problems. Stochastic flows are also used to derive minimum principles in stochastic control, and new equations for the
Evidence of the existence of the low-density liquid phase in supercooled, confined water
Mallamace, Francesco; Broccio, Matteo; Corsaro, Carmelo; Faraone, Antonio; Majolino, Domenico; Venuti, Valentina; Liu, Li; Mou, Chung-Yuan; Chen, Sow-Hsin
2006-01-01
By confining water in a nanoporous structure so narrow that the liquid could not freeze, it is possible to study properties of this previously undescribed system well below its homogeneous nucleation temperature TH = 231 K. Using this trick, we were able to study, by means of a Fourier transform infrared spectroscopy, vibrational spectra (HOH bending and OH-stretching modes) of deeply supercooled water in the temperature range 183 < T < 273 K. We observed, upon decreasing temperature, the bui...
2009-05-01
University of California, Santa Barbara, for his thoughtful comments and insights on the results of our analyses. Our project benefitted greatly from...whales (Orcinus orca ), and coastal spotted dolphins. Image Quality Analysis (IQA; Wang et al. 2004), a quantitative, spatially-explicit method for...436 Creation of a captive broodstock program for southern Coho Salmon (Oncorhynchus kisutch): Results from the initial rearing and spawning
KDE-Track: An Efficient Dynamic Density Estimator for Data Streams
Qahtan, Abdulhakim Ali Ali
2016-11-08
Recent developments in sensors, global positioning system devices and smart phones have increased the availability of spatiotemporal data streams. Developing models for mining such streams is challenged by the huge amount of data that cannot be stored in the memory, the high arrival speed and the dynamic changes in the data distribution. Density estimation is an important technique in stream mining for a wide variety of applications. The construction of kernel density estimators is well studied and documented. However, existing techniques are either expensive or inaccurate and unable to capture the changes in the data distribution. In this paper, we present a method called KDE-Track to estimate the density of spatiotemporal data streams. KDE-Track can efficiently estimate the density function with linear time complexity using interpolation on a kernel model, which is incrementally updated upon the arrival of new samples from the stream. We also propose an accurate and efficient method for selecting the bandwidth value for the kernel density estimator, which increases its accuracy significantly. Both theoretical analysis and experimental validation show that KDE-Track outperforms a set of baseline methods on the estimation accuracy and computing time of complex density structures in data streams.
Asymptotic Existence of Nearly Kirkman Systems
沈灏; 储文松
1994-01-01
It is proved in this paper that,for any given positive integer k≥2,there exists a constant v0=v0(k) such that for v≥v0,the necessary condition v=0 (mod k(k-)) for the existence of a nearly Kirkman system NKS (2,k,v) is also sufficient.Thus we have completely determined the asymptotic existence of NKS.
Yu, Haibo; Zhao, Junning
2017-01-01
In this paper, we study the global existence for classical solutions to the 3D isentropic compressible Navier-Stokes equations in a cuboid domain. Compared to the Cauchy problem studied in Hoff (1995 J. Differ. Equ. 120 215-54), Hoff (2005 J. Math. Fluid Mech. 7 315-38), Huang et al (2012 Commun. Pure Appl. Math. 65 549-85), some new thoughts are applied to obtain upper bounds for density. Precisely, through piecewise estimation and some time-depending a priori estimates, we establish time-uniform upper bounds for density under the assumption that the initial energy is small. The initial vacuum is allowed.
Do Phantom Cuntz-Krieger Algebras Exist?
Arklint, Sara E.
2013-01-01
If phantom Cuntz-Krieger algebras do not exist, then purely infinite Cuntz-Krieger algebras can be characterized by outer properties. In this survey paper, a summary of the known results on non-existence of phantom Cuntz-Krieger algebras is given......If phantom Cuntz-Krieger algebras do not exist, then purely infinite Cuntz-Krieger algebras can be characterized by outer properties. In this survey paper, a summary of the known results on non-existence of phantom Cuntz-Krieger algebras is given...
Krishnamoorthy, Sriram; Daily, Jeffrey A.; Vishnu, Abhinav; Palmer, Bruce J.
2015-11-01
Global Arrays (GA) is a distributed-memory programming model that allows for shared-memory-style programming combined with one-sided communication, to create a set of tools that combine high performance with ease-of-use. GA exposes a relatively straightforward programming abstraction, while supporting fully-distributed data structures, locality of reference, and high-performance communication. GA was originally formulated in the early 1990’s to provide a communication layer for the Northwest Chemistry (NWChem) suite of chemistry modeling codes that was being developed concurrently.
Buecking, N.
2007-11-05
In this work a new theoretical formalism is introduced in order to simulate the phononinduced relaxation of a non-equilibrium distribution to equilibrium at a semiconductor surface numerically. The non-equilibrium distribution is effected by an optical excitation. The approach in this thesis is to link two conventional, but approved methods to a new, more global description: while semiconductor surfaces can be investigated accurately by density-functional theory, the dynamical processes in semiconductor heterostructures are successfully described by density matrix theory. In this work, the parameters for density-matrix theory are determined from the results of density-functional calculations. This work is organized in two parts. In Part I, the general fundamentals of the theory are elaborated, covering the fundamentals of canonical quantizations as well as the theory of density-functional and density-matrix theory in 2{sup nd} order Born approximation. While the formalism of density functional theory for structure investigation has been established for a long time and many different codes exist, the requirements for density matrix formalism concerning the geometry and the number of implemented bands exceed the usual possibilities of the existing code in this field. A special attention is therefore attributed to the development of extensions to existing formulations of this theory, where geometrical and fundamental symmetries of the structure and the equations are used. In Part II, the newly developed formalism is applied to a silicon (001)surface in a 2 x 1 reconstruction. As first step, density-functional calculations using the LDA functional are completed, from which the Kohn-Sham-wave functions and eigenvalues are used to calculate interaction matrix elements for the electron-phonon-coupling an the optical excitation. These matrix elements are determined for the optical transitions from valence to conduction bands and for electron-phonon processes inside the
Prof. Ph.D. Ion Bucur
2008-05-01
Full Text Available Globalization, an asymmetric, complex and controversial process has become the center ofthe main theoretical debates at the end of the 20th century. The state itself represents a subject of very differentapproaches which call for reassessing the validity of the opinions regarding its role in the internationalpolitical economy.Mutations occurred on a political and economic level, the reconfiguration of power and of the publicand private notions call for the reconsideration of the traditional vision over the state and its ability ofacting as autonomous author, as well as for the introduction of new standards for assessing its activity.Controversial opinions exist regarding the suzerainty and power of the current state. A significanttheme is represented by the crisis and implosion of national state, by the undermining of not only suzerainty,but also of the idea of national economy. Other globalization theoreticians admit the exacerbatedeffects of such over the internal and external prerogatives of the state. Incontestable, the role of the state informs, but also its relations with the economy.The state is transformed by globalization, yet it will continue to hold an important position in regulatingthe economic and social processes, as well as neo-liberal failures.Globalization is not the end of the state, but it obliges to reconstruction and rethinking of the interventionway and of the action capacity. Arguments regarding the states transformation should not be confoundedwith those regarding its decline.In the same time, globalization is only one of the regress factors, and it doesnt generate only a cortegeof constraints, but also one of opportunities.Even though the state continues to hold an important limit of movement, it confronts the most profoundlegitimacy crisis in its history.
Density Functionals of Chemical Bonding
Mihai V. Putz
2008-06-01
Full Text Available The behavior of electrons in general many-electronic systems throughout the density functionals of energy is reviewed. The basic physico-chemical concepts of density functional theory are employed to highlight the energy role in chemical structure while its extended influence in electronic localization function helps in chemical bonding understanding. In this context the energy functionals accompanied by electronic localization functions may provide a comprehensive description of the global-local levels electronic structures in general and of chemical bonds in special. Becke-Edgecombe and authorÃ¢Â€Â™s Markovian electronic localization functions are discussed at atomic, molecular and solid state levels. Then, the analytical survey of the main workable kinetic, exchange, and correlation density functionals within local and gradient density approximations is undertaken. The hierarchy of various energy functionals is formulated by employing both the parabolic and statistical correlation degree of them with the electronegativity and chemical hardness indices by means of quantitative structure-property relationship (QSPR analysis for basic atomic and molecular systems.
Existence of standard splittings for conformally stationary spacetimes
Javaloyes, Miguel Angel
2008-01-01
Let $(M,g)$ be a spacetime which admits a complete timelike conformal Killing vector field $K$. We prove that $(M,g)$ splits globally as a standard conformastationary spacetime with respect to $K$ if and only if $(M,g)$ is distinguishing (and, thus causally continuous). Causal but non-distinguishing spacetimes with complete stationary vector fields are also exhibited. For the proof, the recently solved ``folk problems'' on smoothability of time functions (moreover, the existence of a {\\em temporal} function) are used.
Recycled fishing nets as reinforcement of existing concrete structures
Sigvardsen, Nina Marie; Bonnerup, Amanda Helena; Ottosen, Lisbeth M.
2016-01-01
Large amounts of fishing nets are discarded every year polluting the oceans with plastic fibers on a global scale. Due to the big fishing industry in Greenland, an alternative use for discarded fishing nets would have a decreasing effect on the amount of marine litter in the Arctic. A use...... for discarded fishing nets could be as fiber-reinforced polymer (FRP) composites for near surface mounted reinforcement (NSMR). NSMR prolongs the lifetime of existing structures, and thus reduces the amount of materials transported to Greenland, reducing CO2-emission and expenses. The effect of NSMR FRP bars...
Existence of non-trivial, vacuum, asymptotically simple spacetimes
Chrúsciel, P T
2002-01-01
We construct non-trivial vacuum spacetimes with a global I sup +. The construction proceeds by proving extension results for initial data sets across compact boundaries, adapting the gluing arguments of Corvino and Schoen. Another application of the extension results is the existence of initial data which are exactly Schwarzschild both near infinity and near each of the connected component of the apparent horizon. Finally, the construction allows one to add Einstein-Rosen bridges to time-symmetric initial data sets at points satisfying a local parity condition, with the perturbation of the metric localized in an arbitrarily small neighbourhood of the bridge. (letter to the editor)
Existence of non-trivial, vacuum, asymptotically simple spacetimes
Chrusciel, Piotr T; Delay, Erwann [Departement de Mathematiques, Faculte des Sciences, Universite de Tours, Parc de Grandmont, F37200 Tours (France)
2002-05-07
We construct non-trivial vacuum spacetimes with a global I{sup +}. The construction proceeds by proving extension results for initial data sets across compact boundaries, adapting the gluing arguments of Corvino and Schoen. Another application of the extension results is the existence of initial data which are exactly Schwarzschild both near infinity and near each of the connected component of the apparent horizon. Finally, the construction allows one to add Einstein-Rosen bridges to time-symmetric initial data sets at points satisfying a local parity condition, with the perturbation of the metric localized in an arbitrarily small neighbourhood of the bridge. (letter to the editor)
Urban development and global sustainability
Ferlaino Fiorenzo
2014-03-01
Full Text Available In the 1950s, the economist Simon Kuznets theorized the existence of a bell-shaped curve describing the correlation between the level of GDP per capita and income inequality. This generated another hypothesis concerning the existence of an inverted-U relationship between income per capita (GDP and environmental impact. By means of a cross-country analysis, the article shows that, at least at the global scale, an Environmental Kuznets Curve (EKC does not exist, but rather an Environmental Urban Curve (EUC. The city exhibits an complex socioeconomic metabolism that we can define in terms of dissipative and resilience territorial structures.
Existence of the time optimal control for robotic manipulators
Wen, J.; Desrochers, A.
1986-01-01
Using Filipov's Theorem, it is shown that the conditions oif nonfinite escape of trajectories, reachability, and convexity of the dynamics over all admissible controls are needed for the existence of a time optimal solution for the robotic equation. With a lower bound for the finite-escape time established using a Liapunov approach, and an upper bound for the time to reach the target established using the exact linearization idea, a single inequality is found which is closely related to the coriolis and the centrifugal terms, the absence of which implies that the domain of existence of the optimal solution can be made arbitrarily large with a large torque constraint. As the work space is finite, this is essentially a global result in practical situations.
Energy Efficiency in the North American Existing Building Stock
NONE
2007-07-01
This report presents the findings of a new assessment of the techno-economic and policy-related efficiency improvement potential in the North American building stock conducted as part of a wider appraisal of existing buildings in member states of the International Energy Agency. It summarizes results and provides insights into the lessons learned through a broader global review of best practice to improve the energy efficiency of existing buildings. At this time, the report is limited to the USA because of the large size of its buildings market. At a later date, a more complete review may include some details about policies and programs in Canada. If resources are available an additional comprehensive review of Canada and Mexico may be performed in the future.
A Dissipative Model for Hydrogen Storage: Existence and Regularity Results
Chiodaroli, Elisabetta
2010-01-01
We prove global existence of a solution to an initial and boundary value problem for a highly nonlinear PDE system. The problem arises from a termomechanical dissipative model describing hydrogen storage by use of metal hydrides. In order to treat the model from an analytical point of view, we formulate it as a phase transition phenomenon thanks to the introduction of a suitable phase variable. Continuum mechanics laws lead to an evolutionary problem involving three state variables: the temperature, the phase parameter and the pressure. The problem thus consists of three coupled partial differential equations combined with initial and boundary conditions. Existence and regularity of the solutions are here investigated by means of a time discretization-a priori estimate-passage to the limit procedure joined with compactness and monotonicity arguments.
GlobalSoilMap and Global Carbon Predictions
Hempel, Jonathan; McBratney, Alex B.; Arrouays, Dominique
consistently produced soil property information at 100 m resolution across the world. This information will aid in solving some of the key environment and societal issues of the day, including food security, global climate change land degradation and carbon sequestration. Data would be produced using mostly......The GlobalSoilMap project is representative of a global consortium of scientific institutions involved in soil survey and soil science. The GlobalSoilMap group was formed as an outgrowth of the International Union of Soil Sciences Working Group for Digital Soil Mapping with the purpose of providing...... the storehouse of existing legacy soils data along with geographic information and a range of covariates. A range of modeling techniques is used dependant on the complexity of the background soil survey information. The key soil properties that would be most useful to the modeling community and other users are...
God exists with probability 1/(H+1)
Hoey, Jesse
2012-01-01
This note will address the issue of the existence of God from a game theoretic perspective. We will show that, under certain assumptions, man cannot simultaneously be (i) rational and (ii) believe that an infinitely powerful God exists. Game theory and decision theory have long been used to address this thorny question.
Existence Regions of Shock Wave Triple Configurations
Bulat, Pavel V.; Chernyshev, Mikhail V.
2016-01-01
The aim of the research is to create the classification for shock wave triple configurations and their existence regions of various types: type 1, type 2, type 3. Analytical solutions for limit Mach numbers and passing shock intensity that define existence region of every type of triple configuration have been acquired. The ratios that conjugate…
On the existence of consistent price systems
Bayraktar, Erhan; Pakkanen, Mikko S.; Sayit, Hasanjan
2014-01-01
We formulate a sufficient condition for the existence of a consistent price system (CPS), which is weaker than the conditional full support condition (CFS). We use the new condition to show the existence of CPSs for certain processes that fail to have the CFS property. In particular this condition...
Chong Qing CHENG
2011-01-01
Given an integrable Hamiltonian ho with n-degrees of freedom and a Diophantine frequency w, then, arbitrarily close to ho in the Cr topology with r ＜ 2n, there exists an analytical Hamiltonian h∈ with no KAM torus of rotation vector w. In contrast with it, KAM tori exist if perturbations are small in Cr topology with r ＞ 2n.
Structural reliability of existing city bridges
Hellebrandt, L.; Steenbergen, R.; Vrouwenvelder, T.; Blom, K.
2015-01-01
Full probabilistic reliability analysis may be valuable for assessing existing structures. Measures for increasing the safety level are quite costly for existing structures and may be unnecessary when such a decision is grounded on a conservative analysis for determining the structural reliability.
10 CFR 1040.72 - Existing facilities.
2010-01-01
... 10 Energy 4 2010-01-01 2010-01-01 false Existing facilities. 1040.72 Section 1040.72 Energy... § 1040.72 Existing facilities. (a) Accessibility. A recipient shall operate any program or activity to... facilities or every part of a facility accessible to and useable by handicapped persons. (b) Methods. A...
On determining if a specular point exists
Rusch, W; Sørensen, O
1979-01-01
A technique is presented whereby the existence of a specular point on a convex surface of revolution can be determined without actually finding it. Only the evaluation of two simple algebraic expressions is involved. Should a specular point be found not to exist, a search procedure has been thereby...
Some existence and sufficient conditions of optimality
Assefi, T.
1976-01-01
The role of the existence and sufficiency conditions in the field of optimal control was briefly described. The existence theorems are discussed for general nonlinear systems. However, the sufficiency conditions pertain to "nearly" linear systems with integral convex costs. Moreover, a brief discussion of linear systems with multiple-cost functions is presented.
43 CFR 17.217 - Existing facilities.
2010-10-01
... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Existing facilities. 17.217 Section 17.217... facilities. (a) Accessibility. A recipient shall operate each program or activity so that when each part is... not require a recipient to make each of its existing facilities or every part of a facility...
Estimation of the Distribution of Global Anthropogenic Heat Flux
2012-01-01
The radiance lights data in 2006 from the National Oceanic and Atmospheric Administration Air Force Defense Meteorological Satellite Program/Operational Linescan System （DMSP/OLS） and authoritative energy data distributed by the United State Energy Information Administration were applied to estimate the global distribution of anthropogenic heat flux.A strong linear relationship was found to exist between the anthropogenic heat flux and the DMSP/OLS radiance data.On a global scale,the average value of anthropogenic heat flux is approximately 0.03 W m 2 and 0.10 W m 2 for global land area.The results indicate that global anthropogenic heat flux was geographically concentrated and distributed,fundamentally correlating to the economical activities.The anthropogenic heat flux concentrated in the economically developed areas including East Asia,Europe,and eastern North America.The anthropogenic heat flux in the concentrated regions,including the northeastern United States,Central Europe,United Kingdom,Japan,India,and East and South China is much larger than global average level,reaching a large enough value that could affect regional climate.In the center of the concentrated area,the anthropogenic heat flux density may exceed 100 W m 2,according to the results of the model.In developing areas,including South America,Central and North China,India,East Europe,and Middle East,the anthropogenic heat flux can reach a level of more than 10 W m 2 ;however,the anthropogenic heat flux in a vast area,including Africa,Central and North Asia,and South America,is low.With the development of global economy and urban agglomerations,the effect on climate of anthropogenic heat is essential for the research of climate change.
GLOBAL SOLUTIONS OF NONLINEAR SCHRODINGER EQUATIONS
Ye Yaojun
2005-01-01
In this paper we study the existence of global solutions to the Cauchy problem of nonlinear Schrodinger equation by establishing time weight function spaces and using the contraction mapping principle.
Existence test for asynchronous interval iterations
Madsen, Kaj; Caprani, O.; Stauning, Ole
1997-01-01
In the search for regions that contain fixed points ofa real function of several variables, tests based on interval calculationscan be used to establish existence ornon-existence of fixed points in regions that are examined in the course ofthe search. The search can e.g. be performed...... as a synchronous (sequential) interval iteration:In each iteration step all components of the iterate are calculatedbased on the previous iterate. In this case it is straight forward to base simple interval existence and non-existencetests on the calculations done in each step of the iteration. The search can also...... be performed as an asynchronous (parallel) iteration: Only a few components are changed in each stepand this calculation is in general based on components from differentprevious iterates. For the asynchronous iteration it turns out thatsimple tests of existence and non-existence can be based...
Global environmental policy; Globale Umweltpolitik
Varwick, J. (ed.)
2008-07-01
For some years, the interest in global environmental problems and global environmental policy increased substantially. In order to prevent a sustainable and irreversible damage of the global ecological systems, it requires an ecological restructuring of the economy of the industrial nations and a environmental compatible development in the developing countries. Under this aspect, the book under consideration dedicates itself to this problem by means of five scientific contributions: (a) The principle sustainability (Felix Ekardt); (b) Climate change as a world problem (Andreas Rechkemmer); (c) The role of the pioneer of the European Union in the international climate policy: Successes and challenges (Sebastian Oberthuer); (d) Cause for conflict water (Tobias Lindenberg); (e) Environmental political instruments in theory and practice (Johanna Reichenbach/Till Requate). Instruction practice also is concerned with a cross section topic consisting of environmental and European politics: Competent instructions concerning to the European Union - an instruction series for the secondary school I (George Wiesseno, Valentin Eck). Two forum contributions go beyond the topic: (a) Against rigid (society-)political borders in the science (Tim Engartner); (b) Elections in Hamburg - Schwarz-Gruen as new coalition model for the federation? In the column 'the current topic' Gotthard Breit reports on the protests against China on the occasion of the Olympic Games 2008. The author focuses some strangenesses in the debate and pleads for a sober view of the topic. With a report on 'the Beutelsbacher discussions' at 18th to 20th February, 2008, Timo Web finishes this book.
Global teaching of global seismology
Stein, S.; Wysession, M.
2005-12-01
Our recent textbook, Introduction to Seismology, Earthquakes, & Earth Structure (Blackwell, 2003) is used in many countries. Part of the reason for this may be our deliberate attempt to write the book for an international audience. This effort appears in several ways. We stress seismology's long tradition of global data interchange. Our brief discussions of the science's history illustrate the contributions of scientists around the world. Perhaps most importantly, our discussions of earthquakes, tectonics, and seismic hazards take a global view. Many examples are from North America, whereas others are from other areas. Our view is that non-North American students should be exposed to North American examples that are type examples, and that North American students should be similarly exposed to examples elsewhere. For example, we illustrate how the Euler vector geometry changes a plate boundary from spreading, to strike-slip, to convergence using both the Pacific-North America boundary from the Gulf of California to Alaska and the Eurasia-Africa boundary from the Azores to the Mediterranean. We illustrate diffuse plate boundary zones using western North America, the Andes, the Himalayas, the Mediterranean, and the East Africa Rift. The subduction zone discussions examine Japan, Tonga, and Chile. We discuss significant earthquakes both in the U.S. and elsewhere, and explore hazard mitigation issues in different contexts. Both comments from foreign colleagues and our experience lecturing overseas indicate that this approach works well. Beyond the specifics of our text, we believe that such a global approach is facilitated by the international traditions of the earth sciences and the world youth culture that gives students worldwide common culture. For example, a video of the scene in New Madrid, Missouri that arose from a nonsensical earthquake prediction in 1990 elicits similar responses from American and European students.
A Holling Type II Pest and Natural Enemy Model with Density Dependent IPM Strategy
Xia Wang
2017-01-01
Full Text Available Resource limitations and density dependent releasing of natural enemies during the pest control and integrated pest management will undoubtedly result in nonlinear impulsive control. In order to investigate the effects of those nonlinear control strategies on the successful pest control, we have proposed a pest-natural enemy system concerning integrated pest management with density dependent instant killing rate and releasing rate. In particular, the releasing rate depicts how the number of natural enemy populations released was guided by their current density at the fixed moment. The threshold condition which ensures the existence and global stability of pest-free periodic solution has been discussed first, and the effects of key parameters on the threshold condition reveal that reducing the pulse period does not always benefit pest control; that is, frequent releasing of natural enemies may not be beneficial to the eradication of pests when the density dependent releasing method has been implemented. Moreover, the forward and backward bifurcations could occur once the pest-free periodic solution becomes unstable, and the system could exist with very complex dynamics. All those results confirm that the control actions should be carefully designed once the nonlinear impulsive control measures have been taken for pest management.
Wykrzyknik - istnienie - zmiana (Exclamation - Existence - Change
Maciej Karpiński
2011-06-01
Full Text Available It, what exists, so to say, demands for the addressee – the thing exists in the face of (for something (or somebody. In other words, the existence is the relation. The competitive conception of the existence outside the relation (existence isolated leads to the contradiction. The existential proposition ‘Some A exists’, understoodliterally, is the pleonasm. It tends to treat the existential proposition as the conventional figure, expressing the simple act of an A affirmation (the exclamation ‘A!’. The existence’s relation should not be narrowed down only to the relation of perception(esse est percipi. It is needed to be understood widely, as every relation, in which something influences on whatever (that is, some change occurs. This influence (change can take place both inside or outside the consciousness. The existing thing, the influence exerted by it, and the change, occurred as the result of this influence, are identical. Thanks to it, we can eliminate difficulties connected withfinding ‘the point of contact’ between modules of the existence’s relation (that is, ‘the place’ where existing thing and its addressee are connected. The existence, as the relation of influence-change, is modal and gradual (as regards both intensity and extensiveness: the thing, in different aspects, can exist more or less. Theoretically, discussed relation can be symmetrical or antisymmetrical. The concept of error should be redefined. The error concerning the existence (resp. the nonexistence of specified thing, must not mean the incompatibility between this thing and the perception (widely: between this thing and the change causedby this thing in its addressee. The existence is the unity of the thing-perception (resp. the thing-influence-change. That is why the incompatibility can occur only between the state of thing-perception (resp. the thing-influence-change and the related state of duty. The conception of the existence as the relation
Existence and non-existence results for the SU(3) singular Toda system on compact surfaces
Battaglia, Luca; Malchiodi, Andrea
2015-01-01
We consider the SU(3) Toda system on a compact surface. We give both existence and non-existence results under some conditions on the parameters. Existence results are obtained using variational methods, which involve a geometric inequality of new type; non-existence results are obtained using blow-up analysis and localized Pohozaev identities.
The SXI telescope on board EXIST: scientific performances
Natalucci, L; Campana, S; Caraveo, P; Della Ceca, R; Grindlay, J E; Panessa, F; Pareschi, G; Ramsey, B; Tagliaferri, G; Ubertini, P; Villa, G
2009-01-01
The SXI telescope is one of the three instruments on board EXIST, a multiwavelength observatory in charge of performing a global survey of the sky in hard X-rays searching for Supermassive Black Holes. One of the primary objectives of EXIST is also to study with unprecedented sensitivity the most unknown high energy sources in the Universe, like high redshift GRBs, which will be pointed promptly by the Spacecraft by autonomous trigger based on hard X-ray localization on board. The recent addition of a soft X-ray telescope to the EXIST payload complement, with an effective area of ~950 cm2 in the energy band 0.2-3 keV and extended response up to 10 keV will allow to make broadband studies from 0.1 to 600 keV. In particular, investigations of the spectra components and states of AGNs and monitoring of variability of sources, study of the prompt and afterglow emission of GRBs since the early phases, which will help to constrain the emission models and finally, help the identification of sources in the EXIST hard...
Houghton, John
2005-06-01
'Global warming' is a phrase that refers to the effect on the climate of human activities, in particular the burning of fossil fuels (coal, oil and gas) and large-scale deforestation, which cause emissions to the atmosphere of large amounts of 'greenhouse gases', of which the most important is carbon dioxide. Such gases absorb infrared radiation emitted by the Earth's surface and act as blankets over the surface keeping it warmer than it would otherwise be. Associated with this warming are changes of climate. The basic science of the 'greenhouse effect' that leads to the warming is well understood. More detailed understanding relies on numerical models of the climate that integrate the basic dynamical and physical equations describing the complete climate system. Many of the likely characteristics of the resulting changes in climate (such as more frequent heat waves, increases in rainfall, increase in frequency and intensity of many extreme climate events) can be identified. Substantial uncertainties remain in knowledge of some of the feedbacks within the climate system (that affect the overall magnitude of change) and in much of the detail of likely regional change. Because of its negative impacts on human communities (including for instance substantial sea-level rise) and on ecosystems, global warming is the most important environmental problem the world faces. Adaptation to the inevitable impacts and mitigation to reduce their magnitude are both necessary. International action is being taken by the world's scientific and political communities. Because of the need for urgent action, the greatest challenge is to move rapidly to much increased energy efficiency and to non-fossil-fuel energy sources.
Global Optimization by Energy Landscape Paving
Wille, L T; Wille, Luc T.
2002-01-01
We introduce a novel heuristic global optimization method, energy landscape paving (ELP), which combines core ideas from energy surface deformation and tabu search. In appropriate limits, ELP reduces to existing techniques. The approach is very general and flexible and is illustrated here on two protein folding problems. For these examples, the technique gives faster convergence to the global minimum than previous approaches.
Existence theorems for ordinary differential equations
Murray, Francis J
2007-01-01
Theorems stating the existence of an object-such as the solution to a problem or equation-are known as existence theorems. This text examines fundamental and general existence theorems, along with the Picard iterants, and applies them to properties of solutions and linear differential equations.The authors assume a basic knowledge of real function theory, and for certain specialized results, of elementary functions of a complex variable. They do not consider the elementary methods for solving certain special differential equations, nor advanced specialized topics; within these restrictions, th
U.S. Environmental Protection Agency — Road density is generally highly correlated with amount of developed land cover. High road densities usually indicate high levels of ecological disturbance. More...
Improving Global Health Education: Development of a Global Health Competency Model
Ablah, Elizabeth; Biberman, Dorothy A.; Weist, Elizabeth M.; Buekens, Pierre; Bentley, Margaret E.; Burke, Donald; Finnegan, John R.; Flahault, Antoine; Frenk, Julio; Gotsch, Audrey R.; Klag, Michael J.; Lopez, Mario Henry Rodriguez; Nasca, Philip; Shortell, Stephen; Spencer, Harrison C.
2014-01-01
Although global health is a recommended content area for the future of education in public health, no standardized global health competency model existed for master-level public health students. Without such a competency model, academic institutions are challenged to ensure that students are able to demonstrate the knowledge, skills, and attitudes (KSAs) needed for successful performance in today's global health workforce. The Association of Schools of Public Health (ASPH) sought to address this need by facilitating the development of a global health competency model through a multistage modified-Delphi process. Practitioners and academic global health experts provided leadership and guidance throughout the competency development process. The resulting product, the Global Health Competency Model 1.1, includes seven domains and 36 competencies. The Global Health Competency Model 1.1 provides a platform for engaging educators, students, and global health employers in discussion of the KSAs needed to improve human health on a global scale. PMID:24445206
Nielsen, Rikke Kristine
2017-01-01
This paper addresses the call for identification of organizational contingencies related to global mindset, exploration of different forms of global mindset and their relationship with global strategies (Osland, Bird, Mendenhall & Osland, 2006). To this end, this paper explores global mindset...
Shades and Penumbra of Globalization
Mircea PERPELEA
2015-09-01
Full Text Available Those who are often identified as challengers of globalization, from the standpoint of defending a defined modernity since the inception of capitalism1, they are, in most cases, only one or all of the contestants of the dominant paradigm of globalization. Almost no one denies that requires empirical reality - that the current world is changing, both in the most developed societies, and as a result their impact on other companies, globally. Change exists and it is not contested. Its interpretations are contested and the practice based on these interpretations that are to be adopted in relation to them. Stating that this practice is itself a component of globalization, one of the factors that shape, may extend or limit his influence and can “tame” those it deems undesirable effects. Therefore, the debate about globalization acquires exceptional importance in relation to reality. Because it has become one of the most important components of this reality, yet we, that is globalization. And because the way in which reality will evolve from now on will depend, in turn, how that will evolve debate about globalization, building intellectual infrastructure, knowledge and value that will underpin future political and economic action. As stated, rightly, Immanuel Wallerstein, just we humans are the ones who, through their ideas, beliefs and actions constitute uncertainty factors of the future.
Design and Environment, 1972
1972-01-01
Three-part report pinpointing problems and uncovering solutions for the dual concepts of density (ratio of people to space) and crowding (psychological response to density). Section one, A Primer on Crowding,'' reviews new psychological and social findings; section two, Density in the Suburbs,'' shows conflict between status quo and increased…
Physical Relativism as an Interpretation of Existence
Heinrich, Stuart
2013-01-01
Despite the success of modern physics in formulating mathematical theories that can predict the outcome of quantum-scale experiments, the physical interpretations of these theories remain controversial. In this manuscript, we propose a new interpretation of existence that we call physical relativism. Under physical relativism, the difference between mathematical existence and physical existence is clarified, and Wheeler's `it from bit' viewpoint can be objectively evaluated. In addition, physical relativism provides a simple answer to the question of why the universe exists at all, and permits us to derive the maximally biophilic principle, a generalization of the anthropic principle that ascribes high prior likelihood to the observation of a universe with simple physical laws supporting the overall concepts of time, space and the emergent evolution of life.
US Forest Service LANDFIRE Existing Vegetation
US Forest Service, Department of Agriculture — LANDFIRE Existing Vegetation is mapped using predictive landscape models based on extensive field-referenced data, satellite imagery and biophysical gradient layers...
LANDFIRE (90m) Existing Vegetation Type
U.S. Geological Survey, Department of the Interior — This map depicts the distribution of existing vegetation types contained in the LANDFIRE dataset. All 30-meter EVT grids were resampled to 90-meter grids and merged...
Pre-Existing Condition Insurance Plan Data
U.S. Department of Health & Human Services — The Affordable Care Act created the new Pre-Existing Condition Insurance Plan (PCIP) program to make health insurance available to Americans denied coverage by...
Do labour supply and demand curves exist?
Fleetwood, S.
2014-01-01
The objective of this paper is to show that circumstantial and empirical evidence for the existence of labour supply and demand curves is at best inconclusive and at worst casts doubt on their existence. Because virtually all orthodox models of labour markets, simple and complex, are built upon the foundation stones of labour supply and demand curves, these models lack empirically supported foundations. Orthodox labour economists must, therefore, either provide stronger evidence or stop using...
Constraint for the Existence of Ellipsoidal Vesicles
XIE Yu-Zhang
2000-01-01
Under the spontaneous curvature model of lipid bilayers, the constraints for the existence of equilibrium axisym metric oblate and prolate ellipsoidal vesicles are obtained from the general shape equation. They degenerate either to the constraint for the existence of a spherical vesicle or to that of a circular cylindrical vesicle given by Ou-Yang and Helfrich [Phys. Rev. Lett. 59 (1987) 2486; 60(1988)120; Phys. Rev. A 39 (1989) 5280].
Functional interpretation and the existence property
Jørgensen, Klaus Frovin
2004-01-01
It is shown that functional interpretation can be used to show the existence property of intuitionistic number theory. On the basis of truth variants a comparison is then made between realisability and functional interpretation showing a structural difference between the two.......It is shown that functional interpretation can be used to show the existence property of intuitionistic number theory. On the basis of truth variants a comparison is then made between realisability and functional interpretation showing a structural difference between the two....
GLOBALIZATION AND IMPORT RISKS
Popa Ioan
2014-07-01
Full Text Available Delocalization of production and diversification of the sources of offer in the global market place the issue of protection of consumer rights in major consumption centres, namely the European Union in a new light. A review of policies for the protection of consumer rights in the EU, USA and China, reveals major differences regarding the protection of consumer rights and the existence of gaps, and in particular the implementation of effective legislation in this regard. As such, the risks associated with imports have become a major concern in the European Union. The consumer has – one can say – a central role in the globalization process, which justifies the measures aimed at its protection. Although worldwide there are major differences in the degree of market regulation in matters of protection of consumer rights, the trend is the continuous adaptation of the offer to the requirements of global demand. However, one can still find significant gaps which translate into risks specific to the consumers in developed countries, namely in the EU. An important issue arises from this radical change of the localization of production centres in relation to the main consumption centres. While in the developed world, consumer rights protection has reached high levels both by creating an appropriate legislative framework and through consumer awareness and activism regarding their rights, in areas where much of the offer comes from the Western market (China, India, etc. modern mentality on the protection of consumer rights is just emerging. A major requirement is therefore the provision of a status of the consumer compatible with the benefits and risks of globalization, a status defined by safety and protection of imports. This paper confirms the thesis that, ultimately, the main factor counteracting the risks in matters of protection of consumer rights is the consumer, its awareness of its rights.
Strategic Global Climate Command?
Long, J. C. S.
2016-12-01
Researchers have been exploring geoengineering because Anthropogenic GHG emissions could drive the globe towards unihabitability for people, wildlife and vegetation. Potential global deployment of these technologies is inherently strategic. For example, solar radiation management to reflect more sunlight might be strategically useful during a period of time where the population completes an effort to cease emissions and carbon removal technologies might then be strategically deployed to move the atmospheric concentrations back to a safer level. Consequently, deployment of these global technologies requires the ability to think and act strategically on the part of the planet's governments. Such capacity most definitely does not exist today but it behooves scientists and engineers to be involved in thinking through how global command might develop because the way they do the research could support the development of a capacity to deploy intervention rationally -- or irrationally. Internationalizing research would get countries used to working together. Organizing the research in a step-wise manner where at each step scientists become skilled at explaining what they have learned, the quality of the information they have, what they don't know and what more they can do to reduce or handle uncertainty, etc. Such a process can increase societal confidence in being able to make wise decisions about deployment. Global capacity will also be enhanced if the sceintific establishment reinvents misssion driven research so that the programs will identify the systemic issues invovled in any proposed technology and systematically address them with research while still encouraging individual creativity. Geoengineering will diverge from climate science in that geoengineering research needs to design interventions for some publically desirable goal and investigates whether a proposed intervention will acheive desired outcomes. The effort must be a systems-engineering design problem
Globalization and deficit and limitations of global governance
Stojanović Stanislav
2016-01-01
Full Text Available Character and dynamics of relationships in international politics, in which the stronger return to real politics content in the functioning of the foreign policy of the great powers, unequivocally affirms that globalization does not work to its declining power that is less credible design concept of modern world society. The global financial collapse that hit the world in 2008 is a convincing indication that most of the globalization is discredited. The belief in one humanity is becoming a less desirable concept. At the same time, with the increase in global issues that require solving, there are numerous human activities that involve unique or international regulation. The world is increasingly one homeostatic system of interdependent parts of a continent where many aspects of the borders between countries are difficult or even impossible to sustain. Hence the importance of global factors, some of which will fully depend on the articulation of individual and community life of people in the future, stressing the importance of the issue of joint management to ensure global peace and security and promote the prosperity around the world in a universally acceptable and effective way. Therefore, the demonstrated substantial shortcomings of global governance of the world, although they discourage belief in humanity, did not reduce the objective need for global access to many amenities of modern human existence. Many aspects of security, ranging from the security of the individual to the energy and environmental security in modern conditions are not conceivable without international access. However, global security management has been associated with numerous limitations and challenges.
Crystalline structure of accretion disks: features of a global model.
Montani, Giovanni; Benini, Riccardo
2011-08-01
In this paper, we develop the analysis of a two-dimensional magnetohydrodynamical configuration for an axially symmetric and rotating plasma (embedded in a dipolelike magnetic field), modeling the structure of a thin accretion disk around a compact astrophysical object. Our study investigates the global profile of the disk plasma, in order to fix the conditions for the existence of a crystalline morphology and ring sequence, as outlined by the local analysis pursued in Coppi [Phys. Plasmas 12, 7302 (2005)] and Coppi and Rousseau [Astrophys. J. 641, 458 (2006)]. In the linear regime, when the electromagnetic back-reaction of the plasma is small enough, we show the existence of an oscillating radial behavior for the flux surface function, which very closely resembles the one outlined in the local model, apart from a radial modulation of the amplitude. In the opposite limit, corresponding to a dominant back-reaction in the magnetic structure over the field of central object, we can recognize the existence of a ringlike decomposition of the disk, according to the same modulation of the magnetic flux surface, and a smoother radial decay of the disk density, with respect to the linear case. In this extreme nonlinear regime, the global model seems to predict a configuration very close to that of the local analysis, but here the thermostatic pressure, crucial for the equilibrium setting, is also radially modulated. Among the conditions requested for the validity of such a global model, the confinement of the radial coordinate within a given value sensitive to the disk temperature and to the mass of the central objet, stands; however, this condition corresponds to dealing with a thin disk configuration.
Robust Evaluation of Multivariate Density Forecasts
Dovern, Jonas; Manner, Hans
2016-01-01
We derive new tests for proper calibration of multivariate density forecasts based on Rosenblatt probability integral transforms. These tests have the advantage that they i) do not depend on the ordering of variables in the forecasting model, ii) are applicable to densities of arbitrary dimensions, and iii) have superior power relative to existing approaches. We furthermore develop adjusted tests that allow for estimated parameters and, consequently, can be used as in-sample specification tes...
Development of New Density Functional Approximations
Su, Neil Qiang; Xu, Xin
2017-05-01
Kohn-Sham density functional theory has become the leading electronic structure method for atoms, molecules, and extended systems. It is in principle exact, but any practical application must rely on density functional approximations (DFAs) for the exchange-correlation energy. Here we emphasize four aspects of the subject: (a) philosophies and strategies for developing DFAs; (b) classification of DFAs; (c) major sources of error in existing DFAs; and (d) some recent developments and future directions.
Sum rules and spectral density flow in QCD and in superconformal theories
Costantini Antonio
2014-01-01
Full Text Available We discuss the signature of the anomalous breaking of the superconformal symmetry in N${\\cal N}$ = 1 super Yang Mills theory and its manifestation in the form of anomaly poles. Moreover, we describe the massive deformations of the N${\\cal N}$ = 1 theory and the spectral densities of the corresponding anomaly form factors. These are characterized by spectral densities which flow with the mass deformation and turn the continuum contributions from the two-particle cuts of the intermediate states into poles, with a single sum rule satisfied by each component. The poles can be interpreted as signaling the exchange of a composite axion/dilaton/dilatino (ADD multiplet in the effective Lagrangian. We conclude that global anomalous currents characterized by a single flow in the perturbative picture always predict the existence of composite interpolating fields.
Effect of dark matter halo on global spiral modes in galaxies
Ghosh, Soumavo; Saini, Tarun Deep; Jog, Chanda J.
2016-02-01
Low surface brightness (LSB) galaxies form a major class of galaxies, and are characterized by low disc surface density and low star formation rate. These are known to be dominated by dark matter halo from the innermost regions. Here, we study the role of the dark matter halo on the grand-design, m = 2, spiral modes in a galactic disc by carrying out a global mode analysis in the WKB approximation. The Bohr-Sommerfeld quantization rule is used to determine how many discrete global spiral modes are permitted. First, a typical superthin, LSB galaxy UGC 7321 is studied by taking only the galactic disc, modelled as a fluid; and then the disc embedded in a dark matter halo. We find that both cases permit the existence of global spiral modes. This is in contrast to earlier results where the inclusion of dark matter halo was shown to nearly fully suppress local, swing-amplified spiral features. Although technically global modes are permitted in the fluid model as shown here, we argue that due to lack of tidal interactions, these are not triggered in LSB galaxies. For comparison, we carried out a similar analysis for the Galaxy, for which the dark matter halo does not dominate in the inner regions. We show that here too the dark matter halo has little effect, hence the disc embedded in a halo is also able to support global modes. The derived pattern speed of the global mode agrees fairly well with the observed value for the Galaxy.
B. Alonso
2006-01-01
Full Text Available Un avance significativo dentro del área de la ecología sólo se podrá lograr con la adopción generalizada de un sistema basado en el uso compartido de los datos entre científicos. Esta práctica, apoyada por el desarrollo de metadatos precisos que acompañen a los propios datos, conseguirá aumentar la escala temporal y espacial de los objetos de estudio, ventajas evidentes en un área en la que cuestiones de carácter global como el estudio de los efectos del cambio climático van adquiriendo cada vez mayor importancia. En la actualidad existen numerosos grupos de científicos que trabajan voluntariamente en el desarrollo de herramientas que faciliten a los científicos la documentación y el almacenaje de sus datos. Asimismo, Internet está demostrando ser un potente instrumento para compartirlos. Aprovechar estos recursos es decisión nuestra.
Johnson, Gregory C.; Schmidtko, Sunke; Lyman, John M.
2012-01-01
Temperature and salinity both contribute to ocean density, including its seasonal cycle and spatial patterns in the mixed layer. Temperature and salinity profiles from the Argo Program allow construction and analysis of a global, monthly, mixed layer climatology. Temperature changes dominate the seasonal cycle of mixed layer density in most regions, but salinity changes are dominant in the tropical warm pools, Arctic, and Antarctic. Under the Intertropical Convergence Zone, temperature and sa...
An Analysis of the Vulnerability of Global Drinking Water Access to Climate-related Hazards
Elliott, M.; Banerjee, O.; Christenson, E.; Holcomb, D.; Hamrick, L.; Bartram, J.
2014-12-01
Global drinking water access targets are formulated around "sustainable access." Global climate change (GCC) and associated hazards threaten the sustainability of drinking water supply. Extensive literature exists on the impacts of GCC on precipitation and water resources. However, the literature lacks a credible analysis of the vulnerability of global drinking water access. This research reports on an analysis of the current vulnerability of drinking water access due to three climate-related hazardous events: cyclone, drought and flood. An ArcGIS database was built incorporating the following: population density, hazardous event frequency, drinking water technologies in use and adaptive capacity. Two global grids were incorporated first: (1) LandScanTM global population distribution; and (2) frequency of cyclone, drought and flood from ~1980-2000 from Columbia University Center for Hazards Risk Research (CHRR). Population density was used to characterize cells as urban or rural and country-level urban/rural drinking water technologies in use were added based on the WHO/UNICEF Joint Monitoring Programme data. Expert assessment of the resilience of each technology to each hazardous event based on WHO/DFID Vision 2030 were quantified and added to the database. Finally, country-level adaptive capacity was drawn from the "readiness" parameter of the Global Adaptation Index (GaIn). ArcGIS Model Builder and Python were used to automate the addition of datasets. This presentation will report on the results of this analysis, the first credible attempt to assess the vulnerability of global drinking water access to climate-related hazardous events. This analysis has yielded country-level scores and maps displaying the ranking of exposure score (for flood, drought, cyclone, and all three in aggregate) and the corresponding country-level vulnerability scores and rankings incorporating the impact of drinking water technologies and adaptive capacity (Figure 1).
Can very compact and very massive neutron stars both exist?
Drago, Alessandro; Pagliara, Giuseppe
2013-01-01
The existence of neutron stars with masses of $\\sim 2\\,M_{\\odot}$ requires a stiff equation of state at high densities. On the other hand, the necessary appearance also at high densities of new degrees of freedom, such as hyperons and $\\Delta$ resonances, can lead to a strong softening of the equation of state with resulting maximum masses of $\\sim 1.5\\, M_{\\odot}$ and radii smaller than $\\sim 10$ km. Hints for the existence of compact stellar objects with very small radii have been found in recent statistical analysis of quiescent low-mass X-ray binaries in globular clusters. We propose an interpretation of these two apparently contradicting measurements, large masses and small radii, in terms of two separate families of compact stars: hadronic stars, whose equation of state is soft, can be very compact, while quark stars, whose equation of state is stiff, can be very massive. In this respect an early appearance of $\\Delta$ resonances is crucial to guarantee the stability of the branch of hadronic stars. Our...
Probability densities and Lévy densities
Barndorff-Nielsen, Ole Eiler
For positive Lévy processes (i.e. subordinators) formulae are derived that express the probability density or the distribution function in terms of power series in time t. The applicability of the results to finance and to turbulence is briefly indicated.......For positive Lévy processes (i.e. subordinators) formulae are derived that express the probability density or the distribution function in terms of power series in time t. The applicability of the results to finance and to turbulence is briefly indicated....
Probability densities and Lévy densities
Barndorff-Nielsen, Ole Eiler
For positive Lévy processes (i.e. subordinators) formulae are derived that express the probability density or the distribution function in terms of power series in time t. The applicability of the results to finance and to turbulence is briefly indicated.......For positive Lévy processes (i.e. subordinators) formulae are derived that express the probability density or the distribution function in terms of power series in time t. The applicability of the results to finance and to turbulence is briefly indicated....
CZT imaging detectors for ProtoEXIST
Hong, J; Chammas, N; Copete, A; Baker, R G; Barthelmy, S D; Gehrels, N; Cook, W R; Burnham, J A; Harrison, F A; Collins, J; Craig, W W
2006-01-01
We describe the detector development for a balloon-borne wide-field hard X-ray (20 - 600 keV) telescope, ProtoEXIST. ProtoEXIST is a pathfinder for both technology and science of the proposed implementation of the Black Hole Finder Probe, Energetic X-ray Imaging Survey telescope (EXIST). The principal technology challenge is the development of large area, close-tiled modules of imaging CZT detectors (1000 cm2 for ProtoEXIST1). We review the updates of the detector design and package concept for ProtoEXIST1 and report the current development status of the CZT detectors, using calibration results of our basic detector unit - 2 x 2 x 0.5 cm CZT crystals with 2.5 mm pixels (8 x 8 array). The current prototype (Rev1) of our detector crystal unit (DCU) shows ~4.5 keV electronics noise (FWHM), and the radiation measurements show the energy resolution (FWHM) of the units is 4.7 keV (7.9%) at 59.5 keV, 5.6 keV (4.6%) at 122 keV, and 7.6 keV (2.1%) at 356 keV. The new (Rev2) DCU with revised design is expected to impro...
Objetos intencionais e existência objetiva
Jairo José da Silva
1991-12-01
Full Text Available Neste artigo quero apontar para a possibilidade de uma ontologia da matemática que, mesmo mantendo alguns pontos em comum com o platonismo e com o construtivismo, desliga-se destes em outros pontos essenciais. Por objeto matemático entendo o foco referencial do discurso matemático, ou seja, aquilo sobre o qual a matemática fala. Entendo que a existência destes objetos é meramente intencional, presuntiva, mas, simultaneamente, objetiva, no sentido de ser uma existência comunalizada, compartilhada por todos aqueles engajados no fazer matemático. A existência objetiva das entidades matemáticas não está, entretanto, garantida de uma vez por todas, mas apenas enquanto o discurso matemático for consistente. Este é o espírito do critério de existência objetiva enunciado que, acredito, deve sustentar uma ontologia matemática sem o pressuposto da existência independente de um domínio de objetos matemáticos, sem o empobrecimento que lhe impõem as diferentes versões construtivistas e sem a aniquilação que lhe infringe o formalismo sem objetos.
COMADRE: a global database of animal demography
Salguero-Gómez, R.; Jones, O.R.; Archer, C.R.; Bein, C.; de Buhr, H.; Farack, C.; Gottschalk, F.; Hartmann, A.; Henning, A.; Hoppe, G.; Römer, G.; Ruoff, T.; Sommer, V.; Wille, J.; Voigt, J; Zeh, S.; Vieregg, D.; Buckley, Y.M.; Che-Castaldo, J.; Hodgson, D.; Scheuerlein, A.; Caswell, H.; Vaupel, J.W.
2016-01-01
1. The open-data scientific philosophy is being widely adopted and proving to promote considerable progress in ecology and evolution. Open-data global data bases now exist on animal migration, species distribution, conservation status, etc. However, a gap exists for data on population dynamics spann
Representing a public that does not exist
Korsgaard, Morten Timmermann
and function of the teacher. Confronted by this teachers and educationalists in Denmark have chosen different paths. One current returns to nationalistic and traditional educational ideals and another accepts the global agenda and attempts to find a new form of legitimacy within the ‘what works’ framework......In her seminal essay ‘The Crisis in Education’ Hannah Arendt presents teachers with the challenge of having to represent a world that is becoming out of joint. This means that the teacher stands as a representative of a world that is becoming increasingly inexplicable and incomprehensible......, and the only way of retaining any form of authority (and legitimacy as a teacher) is to remain loyal to the task of presenting this world to the child. This challenge presents itself acutely in the form of a global reform agenda that legitimizes standardisation and accountability while eroding the authority...
Free Boundary Problems and Density Perimeter
Bucur, Dorin; Zolésio, Jean-Paul
1996-04-01
We introduce a new concept "the density perimeter," which substitutes the measure of length of the perimeter of a set in free boundary problems. We deduce some links between the Hausdorff convergence and the char convergence for a family of domains with bounded density perimeter. If this perimeter is considered as a penalty term, we give existence results for the variational problem which appears in computer vision and in a Bernoulli-like free boundary problem. We also make some considerations concerning aΓ-convergence property of the density perimeter
Existing bridge evaluation using deficiency point method
Vičan Josef
2016-01-01
Full Text Available In the transforming EU countries, transportation infrastructure has a prominent position in advancing industry and society. Recent developments show, that attention should be moved from the design of new structures towards the repair and reconstruction of existing ones to ensure and increase their satisfactory structural reliability and durability. The problem is very urgent because many construction projects, especially transport infrastructure, in most European countries are more than 50-60 years old and require rehabilitations based on objective evaluations. Therefore, the paper presents methodology of existing bridge evaluation based on reliability concept using Deficiency Point Method. The methodology was prepared from the viewpoint to determine the priority order for existing bridge rehabilitation.
On the existence of shortest directed networks
Swanepoel, Konrad J
2008-01-01
A directed network connecting a set A to a set B is a digraph containing an a-b path for each a in A and b in B. Vertices in the directed network not in A or B are called Steiner points. We show that in a finitely compact metric space in which geodesics exist, any two finite sets A and B are connected by a shortest directed network. We also bound the number of Steiner points by a function of the sizes of A and B. Previously, such an existence result was known only for the Euclidean plane [M. Alfaro, Pacific J. Math. 167 (1995) 201-214]. The main difficulty is that, unlike the undirected case (Steiner minimal trees), the underlying graphs need not be acyclic. Existence in the undirected case was first shown by E. J. Cockayne [Canad. Math. Bull. 10 (1967) 431-450].
Evidence for the existence of nociceptors in rat thoracolumbar fascia.
Mense, Siegfried; Hoheisel, Ulrich
2016-07-01
Recently, the existence of nociceptive fibers in fascia tissue has attracted much interest. Fascia can be a source of pain in several disorders such as fasciitis and non-specific low back pain. However, little is known about the properties of fascia nociceptors and possible changes of the fascia innervation by nociceptors under pathological circumstances. In this histologic study, the density of presumably nociceptive fibers and free nerve endings was determined in the three layers of the rat TLF: inner layer (IL, covering the multifidus muscle), middle layer (ML) and outer layer (OL). As markers for nociceptive fibers, antibodies to the neuropeptides CGRP and SP as well as to the transient receptor potential vanilloid 1 (TRPV1) were used. As a pathological state, inflammation of the TLF was induced with injection of complete Freund's adjuvant. The density of CGRP- and SP-positive fibers was significantly increased in the inner and outer layer of the inflamed fascia. In the thick middle layer, no inflammation-induced change occurred. In additional experiments, a neurogenic inflammation was induced in the fascia by electrical stimulation of dorsal roots. In these experiments, plasma extravasation was visible in the TLF, which is clear functional evidence for the existence of fascia nociceptors. The presence of nociceptors in the TLF and the increased density of presumably nociceptive fibers under chronic painful circumstances may explain the pain from a pathologically altered fascia. The fascia nociceptors probably contribute also to the pain in non-specific low back pain. Copyright © 2016 Elsevier Ltd. All rights reserved.