Three-Field Modelling of Nonlinear Nonsmooth Boundary Value Problems and Stability of Differential Mixed Variational Inequalities

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J. Gwinner

2013-01-01

Full Text Available The purpose of this paper is twofold. Firstly we consider nonlinear nonsmooth elliptic boundary value problems, and also related parabolic initial boundary value problems that model in a simplified way steady-state unilateral contact with Tresca friction in solid mechanics, respectively, stem from nonlinear transient heat conduction with unilateral boundary conditions. Here a recent duality approach, that augments the classical Babuška-Brezzi saddle point formulation for mixed variational problems to twofold saddle point formulations, is extended to the nonsmooth problems under consideration. This approach leads to variational inequalities of mixed form for three coupled fields as unknowns and to related differential mixed variational inequalities in the time-dependent case. Secondly we are concerned with the stability of the solution set of a general class of differential mixed variational inequalities. Here we present a novel upper set convergence result with respect to perturbations in the data, including perturbations of the associated nonlinear maps, the nonsmooth convex functionals, and the convex constraint set. We employ epiconvergence for the convergence of the functionals and Mosco convergence for set convergence. We impose weak convergence assumptions on the perturbed maps using the monotonicity method of Browder and Minty.

Identifying the principal coefficient of parabolic equations with non-divergent form

International Nuclear Information System (INIS)

Jiang, L S; Bian, B J

2005-01-01

We deal with an inverse problem of determining a coefficient a(x, t) of principal part for second order parabolic equations with non-divergent form when the solution is known. Such a problem has important applications in a large fields of applied science. We propose a well-posed approximate algorithm to identify the coefficient. The existence, uniqueness and stability of such solutions a(x, t) are proved. A necessary condition which is a couple system of a parabolic equation and a parabolic variational inequality is deduced. Our numerical simulations show that the coefficient is recovered very well

Identifying the principal coefficient of parabolic equations with non-divergent form

Science.gov (United States)

Jiang, L. S.; Bian, B. J.

2005-01-01

We deal with an inverse problem of determining a coefficient a(x, t) of principal part for second order parabolic equations with non-divergent form when the solution is known. Such a problem has important applications in a large fields of applied science. We propose a well-posed approximate algorithm to identify the coefficient. The existence, uniqueness and stability of such solutions a(x, t) are proved. A necessary condition which is a couple system of a parabolic equation and a parabolic variational inequality is deduced. Our numerical simulations show that the coefficient is recovered very well.

Homogenization of variational inequalities for obstacle problems

International Nuclear Information System (INIS)

Sandrakov, G V

2005-01-01

Results on the convergence of solutions of variational inequalities for obstacle problems are proved. The variational inequalities are defined by a non-linear monotone operator of the second order with periodic rapidly oscillating coefficients and a sequence of functions characterizing the obstacles. Two-scale and macroscale (homogenized) limiting variational inequalities are obtained. Derivation methods for such inequalities are presented. Connections between the limiting variational inequalities and two-scale and macroscale minimization problems are established in the case of potential operators.

On Gap Functions for Quasi-Variational Inequalities

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Kouichi Taji

2008-01-01

Full Text Available For variational inequalities, various merit functions, such as the gap function, the regularized gap function, the D-gap function and so on, have been proposed. These functions lead to equivalent optimization formulations and are used to optimization-based methods for solving variational inequalities. In this paper, we extend the regularized gap function and the D-gap functions for a quasi-variational inequality, which is a generalization of the variational inequality and is used to formulate generalized equilibrium problems. These extensions are shown to formulate equivalent optimization problems for quasi-variational inequalities and are shown to be continuous and directionally differentiable.

Generalized quasi variational inequalities

Energy Technology Data Exchange (ETDEWEB)

Noor, M.A. [King Saud Univ., Riyadh (Saudi Arabia)

1996-12-31

In this paper, we establish the equivalence between the generalized quasi variational inequalities and the generalized implicit Wiener-Hopf equations using essentially the projection technique. This equivalence is used to suggest and analyze a number of new iterative algorithms for solving generalized quasi variational inequalities and the related complementarity problems. The convergence criteria is also considered. The results proved in this paper represent a significant improvement and refinement of the previously known results.

Multistep Hybrid Extragradient Method for Triple Hierarchical Variational Inequalities

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Zhao-Rong Kong

2013-01-01

Full Text Available We consider a triple hierarchical variational inequality problem (THVIP, that is, a variational inequality problem defined over the set of solutions of another variational inequality problem which is defined over the intersection of the fixed point set of a strict pseudocontractive mapping and the solution set of the classical variational inequality problem. Moreover, we propose a multistep hybrid extragradient method to compute the approximate solutions of the THVIP and present the convergence analysis of the sequence generated by the proposed method. We also derive a solution method for solving a system of hierarchical variational inequalities (SHVI, that is, a system of variational inequalities defined over the intersection of the fixed point set of a strict pseudocontractive mapping and the solution set of the classical variational inequality problem. Under very mild conditions, it is proven that the sequence generated by the proposed method converges strongly to a unique solution of the SHVI.

Variational and quasi-variational inequalities in mechanics

CERN Document Server

Kravchuk, Alexander S

2007-01-01

The essential aim of the present book is to consider a wide set of problems arising in the mathematical modelling of mechanical systems under unilateral constraints. In these investigations elastic and non-elastic deformations, friction and adhesion phenomena are taken into account. All the necessary mathematical tools are given: local boundary value problem formulations, construction of variational equations and inequalities, and the transition to minimization problems, existence and uniqueness theorems, and variational transformations (Friedrichs and Young-Fenchel-Moreau) to dual and saddle-point search problems. Important new results concern contact problems with friction. The Coulomb friction law and some others are considered, in which relative sliding velocities appear. The corresponding quasi-variational inequality is constructed, as well as the appropriate iterative method for its solution. Outlines of the variational approach to non-stationary and dissipative systems and to the construction of the go...

Some remarks on variational and quasi-variational inequalities of monotone operators

International Nuclear Information System (INIS)

Siddiqi, A.H.

1990-08-01

In this paper we study a fairly general class of variational and quasi-variational inequalities problem which represent some important physical phenomena. Several well-known results concerning variational inequalities are special cases of our results. Existence, uniqueness and numerical analysis of this problem have been studied. (author). 39 refs

A study of variational inequalities for set-valued mappings

OpenAIRE

Tarafdar Enayet; Yuan George Xian-Zhi; Tan Kok-Keong

1999-01-01

In this paper, Ky Fan's KKM mapping principle is used to establish the existence of solutions for simultaneous variational inequalities. By applying our earlier results together with Fan–Glicksberg fixed point theorem, we prove some existence results for implicit variational inequalities and implicit quasi-variational inequalities for set-valued mappings which are either monotone or upper semi-continuous.

A study of variational inequalities for set-valued mappings

Directory of Open Access Journals (Sweden)

Tarafdar Enayet

1999-01-01

Full Text Available In this paper, Ky Fan's KKM mapping principle is used to establish the existence of solutions for simultaneous variational inequalities. By applying our earlier results together with Fan–Glicksberg fixed point theorem, we prove some existence results for implicit variational inequalities and implicit quasi-variational inequalities for set-valued mappings which are either monotone or upper semi-continuous.

On Self-Adaptive Method for General Mixed Variational Inequalities

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Abdellah Bnouhachem

2008-01-01

Full Text Available We suggest and analyze a new self-adaptive method for solving general mixed variational inequalities, which can be viewed as an improvement of the method of (Noor 2003. Global convergence of the new method is proved under the same assumptions as Noor's method. Some preliminary computational results are given to illustrate the efficiency of the proposed method. Since the general mixed variational inequalities include general variational inequalities, quasivariational inequalities, and nonlinear (implicit complementarity problems as special cases, results proved in this paper continue to hold for these problems.

General strongly nonlinear variational inequalities

International Nuclear Information System (INIS)

Siddiqi, A.H.; Ansari, Q.H.

1990-07-01

In this paper we develop iterative algorithms for finding approximate solutions for new classes of variational and quasi-variational inequalities which include, as special case, some known results in this field. It is shown that the solutions of the iterative schemes converge to the exact solutions. (author). 15 refs

Coercive properties of elliptic-parabolic operator

International Nuclear Information System (INIS)

Duong Min Duc.

1987-06-01

Using a generalized Poincare inequality, we study the coercive properties of a class of elliptic-parabolic partial differential equations, which contains many degenerate elliptic equations considered by the other authors. (author). 16 refs

Triple Hierarchical Variational Inequalities with Constraints of Mixed Equilibria, Variational Inequalities, Convex Minimization, and Hierarchical Fixed Point Problems

Directory of Open Access Journals (Sweden)

Lu-Chuan Ceng

2014-01-01

Full Text Available We introduce and analyze a hybrid iterative algorithm by virtue of Korpelevich's extragradient method, viscosity approximation method, hybrid steepest-descent method, and averaged mapping approach to the gradient-projection algorithm. It is proven that under appropriate assumptions, the proposed algorithm converges strongly to a common element of the fixed point set of infinitely many nonexpansive mappings, the solution set of finitely many generalized mixed equilibrium problems (GMEPs, the solution set of finitely many variational inequality problems (VIPs, the solution set of general system of variational inequalities (GSVI, and the set of minimizers of convex minimization problem (CMP, which is just a unique solution of a triple hierarchical variational inequality (THVI in a real Hilbert space. In addition, we also consider the application of the proposed algorithm to solve a hierarchical fixed point problem with constraints of finitely many GMEPs, finitely many VIPs, GSVI, and CMP. The results obtained in this paper improve and extend the corresponding results announced by many others.

Controllability and stabilization of parabolic equations

CERN Document Server

Barbu, Viorel

2018-01-01

This monograph presents controllability and stabilization methods in control theory that solve parabolic boundary value problems. Starting from foundational questions on Carleman inequalities for linear parabolic equations, the author addresses the controllability of parabolic equations on a variety of domains and the spectral decomposition technique for representing them. This method is, in fact, designed for use in a wider class of parabolic systems that include the heat and diffusion equations. Later chapters develop another process that employs stabilizing feedback controllers with a finite number of unstable modes, with special attention given to its use in the boundary stabilization of Navier–Stokes equations for the motion of viscous fluid. In turn, these applied methods are used to explore related topics like the exact controllability of stochastic parabolic equations with linear multiplicative noise. Intended for graduate students and researchers working on control problems involving nonlinear diff...

On a class of general variational inequalities

International Nuclear Information System (INIS)

Siddiqi, A.H.

1990-06-01

The study of variational inequalities was initiated by the Italian Mathematician, Guido Stampacchia in the early 60's. Besides several other important problems of Physics and Engineering this theory has been applied to solve the problem of Elasticity with unilateral constraints. In this paper we introduce a new class of variational inequalities and study the existence and uniqueness of its solution. Error estimates, convergence of approximate solution and the penalty method are also discussed. (author). 25 refs

A Modified Alternating Direction Method for Variational Inequality Problems

International Nuclear Information System (INIS)

Han, D.

2002-01-01

The alternating direction method is an attractive method for solving large-scale variational inequality problems whenever the subproblems can be solved efficiently. However, the subproblems are still variational inequality problems, which are as structurally difficult to solve as the original one. To overcome this disadvantage, in this paper we propose a new alternating direction method for solving a class of nonlinear monotone variational inequality problems. In each iteration the method just makes an orthogonal projection to a simple set and some function evaluations. We report some preliminary computational results to illustrate the efficiency of the method

Solvability of Extended General Strongly Mixed Variational Inequalities

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Balwant Singh Thakur

2013-10-01

Full Text Available In this paper, a new class of extended general strongly mixed variational inequalities is introduced and studied in Hilbert spaces. An existence theorem of solution is established and using resolvent operator technique, a new iterative algorithm for solving the extended general strongly mixed variational inequality is suggested. A convergence result for the iterative sequence generated by the new algorithm is also established.

Stability analysis of impulsive parabolic complex networks

Energy Technology Data Exchange (ETDEWEB)

Wang Jinliang, E-mail: wangjinliang1984@yahoo.com.cn [Science and Technology on Aircraft Control Laboratory, School of Automation Science and Electrical Engineering, Beihang University, XueYuan Road, No. 37, HaiDian District, Beijing 100191 (China); Wu Huaining [Science and Technology on Aircraft Control Laboratory, School of Automation Science and Electrical Engineering, Beihang University, XueYuan Road, No. 37, HaiDian District, Beijing 100191 (China)

2011-11-15

Highlights: > Two impulsive parabolic complex network models are proposed. > The global exponential stability of impulsive parabolic complex networks are considered. > The robust global exponential stability of impulsive parabolic complex networks are considered. - Abstract: In the present paper, two kinds of impulsive parabolic complex networks (IPCNs) are considered. In the first one, all nodes have the same time-varying delay. In the second one, different nodes have different time-varying delays. Using the Lyapunov functional method combined with the inequality techniques, some global exponential stability criteria are derived for the IPCNs. Furthermore, several robust global exponential stability conditions are proposed to take uncertainties in the parameters of the IPCNs into account. Finally, numerical simulations are presented to illustrate the effectiveness of the results obtained here.

Stability analysis of impulsive parabolic complex networks

International Nuclear Information System (INIS)

Wang Jinliang; Wu Huaining

2011-01-01

Highlights: → Two impulsive parabolic complex network models are proposed. → The global exponential stability of impulsive parabolic complex networks are considered. → The robust global exponential stability of impulsive parabolic complex networks are considered. - Abstract: In the present paper, two kinds of impulsive parabolic complex networks (IPCNs) are considered. In the first one, all nodes have the same time-varying delay. In the second one, different nodes have different time-varying delays. Using the Lyapunov functional method combined with the inequality techniques, some global exponential stability criteria are derived for the IPCNs. Furthermore, several robust global exponential stability conditions are proposed to take uncertainties in the parameters of the IPCNs into account. Finally, numerical simulations are presented to illustrate the effectiveness of the results obtained here.

Regularization of Nonmonotone Variational Inequalities

International Nuclear Information System (INIS)

Konnov, Igor V.; Ali, M.S.S.; Mazurkevich, E.O.

2006-01-01

In this paper we extend the Tikhonov-Browder regularization scheme from monotone to rather a general class of nonmonotone multivalued variational inequalities. We show that their convergence conditions hold for some classes of perfectly and nonperfectly competitive economic equilibrium problems

Homogenization of variational inequalities and equations defined by pseudomonotone operators

International Nuclear Information System (INIS)

Sandrakov, G V

2008-01-01

Results on the convergence of sequences of solutions of non-linear equations and variational inequalities for obstacle problems are proved. The variational inequalities and equations are defined by a non-linear, pseudomonotone operator of the second order with periodic, rapidly oscillating coefficients and by sequences of functions characterizing the obstacles and the boundary conditions. Two-scale and macroscale (homogenized) limiting problems for such variational inequalities and equations are obtained. Results on the relationship between solutions of these limiting problems are established and sufficient conditions for the uniqueness of solutions are presented. Bibliography: 25 titles

Hybrid Steepest-Descent Methods for Triple Hierarchical Variational Inequalities

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L. C. Ceng

2015-01-01

Full Text Available We introduce and analyze a relaxed iterative algorithm by combining Korpelevich’s extragradient method, hybrid steepest-descent method, and Mann’s iteration method. We prove that, under appropriate assumptions, the proposed algorithm converges strongly to a common element of the fixed point set of infinitely many nonexpansive mappings, the solution set of finitely many generalized mixed equilibrium problems (GMEPs, the solution set of finitely many variational inclusions, and the solution set of general system of variational inequalities (GSVI, which is just a unique solution of a triple hierarchical variational inequality (THVI in a real Hilbert space. In addition, we also consider the application of the proposed algorithm for solving a hierarchical variational inequality problem with constraints of finitely many GMEPs, finitely many variational inclusions, and the GSVI. The results obtained in this paper improve and extend the corresponding results announced by many others.

Identifying an unknown function in a parabolic equation with overspecified data via He's variational iteration method

International Nuclear Information System (INIS)

Dehghan, Mehdi; Tatari, Mehdi

2008-01-01

In this research, the He's variational iteration technique is used for computing an unknown time-dependent parameter in an inverse quasilinear parabolic partial differential equation. Parabolic partial differential equations with overspecified data play a crucial role in applied mathematics and physics, as they appear in various engineering models. The He's variational iteration method is an analytical procedure for finding solutions of differential equations, is based on the use of Lagrange multipliers for identification of an optimal value of a parameter in a functional. To show the efficiency of the new approach, several test problems are presented for one-, two- and three-dimensional cases

Using spectral element method to solve variational inequalities with applications in finance

International Nuclear Information System (INIS)

Moradipour, M.; Yousefi, S.A.

2015-01-01

Under the Black–Scholes model, the value of an American option solves a time dependent variational inequality problem (VIP). In this paper, first we discretize the variational inequality of American option in temporal direction by applying the Rannacher time stepping and achieve a sequence of elliptic variational inequalities. Second we discretize the spatial domain of variational inequalities by using spectral element methods with high order Lagrangian polynomials introduced on Gauss–Legendre–Lobatto points. Also by computing integrals by the Gauss–Legendre–Lobatto quadrature rule we derive a sequence of the linear complementarity problems (LCPs) having a positive definite sparse coefficient matrix. To find the unique solutions of the LCPs, we use the projected successive over-relaxation (PSOR) algorithm. Furthermore we present some existence and uniqueness theorems for the variational inequalities and LCPs. Finally, theoretical results are verified on the relevant numerical examples.

Convex Minimization with Constraints of Systems of Variational Inequalities, Mixed Equilibrium, Variational Inequality, and Fixed Point Problems

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Lu-Chuan Ceng

2014-01-01

Full Text Available We introduce and analyze one iterative algorithm by hybrid shrinking projection method for finding a solution of the minimization problem for a convex and continuously Fréchet differentiable functional, with constraints of several problems: finitely many generalized mixed equilibrium problems, finitely many variational inequalities, the general system of variational inequalities and the fixed point problem of an asymptotically strict pseudocontractive mapping in the intermediate sense in a real Hilbert space. We prove strong convergence theorem for the iterative algorithm under suitable conditions. On the other hand, we also propose another iterative algorithm by hybrid shrinking projection method for finding a fixed point of infinitely many nonexpansive mappings with the same constraints, and derive its strong convergence under mild assumptions.

Parameter choice in Banach space regularization under variational inequalities

International Nuclear Information System (INIS)

Hofmann, Bernd; Mathé, Peter

2012-01-01

The authors study parameter choice strategies for the Tikhonov regularization of nonlinear ill-posed problems in Banach spaces. The effectiveness of any parameter choice for obtaining convergence rates depends on the interplay of the solution smoothness and the nonlinearity structure, and it can be expressed concisely in terms of variational inequalities. Such inequalities are link conditions between the penalty term, the norm misfit and the corresponding error measure. The parameter choices under consideration include an a priori choice, the discrepancy principle as well as the Lepskii principle. For the convenience of the reader, the authors review in an appendix a few instances where the validity of a variational inequality can be established. (paper)

Impurity magnetopolaron in a parabolic quantum dot: the squeezed-state variational approach

International Nuclear Information System (INIS)

Kandemir, B S; Cetin, A

2005-01-01

We present a calculation of the ground-state binding energy of an impurity magnetopolaron confined in a three-dimensional (3D) parabolic quantum dot potential, in the framework of a variational approach based on two successive canonical transformations. First, we apply a displaced-oscillator type unitary transformation to diagonalize the relevant Froehlich Hamiltonian. Second, a single-mode squeezed-state transformation is introduced to deal with bilinear terms arising from the first transformation. Finally, the parameters of these transformations together with the parameters included in the electronic trial wavefunction are determined variationally to obtain the ground-state binding energy of an impurity magnetopolaron confined in a 3D parabolic quantum dot potential. Our approach has two advantages: first, the displaced-oscillator transformation allows one to obtain results valid for whole range of electron-phonon coupling strength since it is a special combination of Lee-Low-Pines and Huybrechts (LLP-H) canonical transformations, and second, the later transformation improves all-coupling results. It has been shown that the effects of quadratic terms arising from the all-coupling approach are very important and should be taken into account in studying the size-dependent physical properties of nanostructured materials

The parabolic equation method for outdoor sound propagation

DEFF Research Database (Denmark)

Arranz, Marta Galindo

The parabolic equation method is a versatile tool for outdoor sound propagation. The present study has focused on the Cranck-Nicolson type Parabolic Equation method (CNPE). Three different applications of the CNPE method have been investigated. The first two applications study variations of the g......The parabolic equation method is a versatile tool for outdoor sound propagation. The present study has focused on the Cranck-Nicolson type Parabolic Equation method (CNPE). Three different applications of the CNPE method have been investigated. The first two applications study variations...

Variational inequalities and flow in porous media

International Nuclear Information System (INIS)

Chipot, M.

1984-01-01

This book is concerned with regularity theory for obstacle problems, and with the dam problem, which, in the rectangular case, is one of the most interesting applications of variational inequalities with an obstacle

Convergence rates in constrained Tikhonov regularization: equivalence of projected source conditions and variational inequalities

International Nuclear Information System (INIS)

Flemming, Jens; Hofmann, Bernd

2011-01-01

In this paper, we enlighten the role of variational inequalities for obtaining convergence rates in Tikhonov regularization of nonlinear ill-posed problems with convex penalty functionals under convexity constraints in Banach spaces. Variational inequalities are able to cover solution smoothness and the structure of nonlinearity in a uniform manner, not only for unconstrained but, as we indicate, also for constrained Tikhonov regularization. In this context, we extend the concept of projected source conditions already known in Hilbert spaces to Banach spaces, and we show in the main theorem that such projected source conditions are to some extent equivalent to certain variational inequalities. The derived variational inequalities immediately yield convergence rates measured by Bregman distances

Measuring total health inequality: adding individual variation to group-level differences

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Gakidou Emmanuela

2002-08-01

Full Text Available Abstract Background Studies have revealed large variations in average health status across social, economic, and other groups. No study exists on the distribution of the risk of ill-health across individuals, either within groups or across all people in a society, and as such a crucial piece of total health inequality has been overlooked. Some of the reason for this neglect has been that the risk of death, which forms the basis for most measures, is impossible to observe directly and difficult to estimate. Methods We develop a measure of total health inequality – encompassing all inequalities among people in a society, including variation between and within groups – by adapting a beta-binomial regression model. We apply it to children under age two in 50 low- and middle-income countries. Our method has been adopted by the World Health Organization and is being implemented in surveys around the world; preliminary estimates have appeared in the World Health Report (2000. Results Countries with similar average child mortality differ considerably in total health inequality. Liberia and Mozambique have the largest inequalities in child survival, while Colombia, the Philippines and Kazakhstan have the lowest levels among the countries measured. Conclusions Total health inequality estimates should be routinely reported alongside average levels of health in populations and groups, as they reveal important policy-related information not otherwise knowable. This approach enables meaningful comparisons of inequality across countries and future analyses of the determinants of inequality.

A New Approximation Method for Solving Variational Inequalities and Fixed Points of Nonexpansive Mappings

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Klin-eam Chakkrid

2009-01-01

Full Text Available Abstract A new approximation method for solving variational inequalities and fixed points of nonexpansive mappings is introduced and studied. We prove strong convergence theorem of the new iterative scheme to a common element of the set of fixed points of nonexpansive mapping and the set of solutions of the variational inequality for the inverse-strongly monotone mapping which solves some variational inequalities. Moreover, we apply our main result to obtain strong convergence to a common fixed point of nonexpansive mapping and strictly pseudocontractive mapping in a Hilbert space.

A Probabilistic Approach to Second Order Variational Inequalities ...

Indian Academy of Sciences (India)

. Under certain conditions we show the existence of a unique viscosity solution of these variational inequalities and give a stochastic representation to this solution. As an application, we study a stochastic game with stopping times and show ...

Solving Variable Coefficient Fourth-Order Parabolic Equation by ...

African Journals Online (AJOL)

Solving Variable Coefficient Fourth-Order Parabolic Equation by Modified initial guess Variational ... variable coefficient fourth order parabolic partial differential equations. The new method shows rapid convergence to the exact solution.

Experimental Validation of a Differential Variational Inequality-Based Approach for Handling Friction and Contact in Vehicle

Science.gov (United States)

2015-11-20

terrain modeled using the discrete element method (DEM). Experimental Validation of a Differential Variational Inequality -Based Approach for Handling...COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Experimental Validation of a Differential Variational Inequality -Based Approach for...sinkage, and single wheel tests. 1.1. Modeling Frictional Contact Via Differential Variational Inequalities Consider a three dimensional (3D) system of

The finite element method scheme for a solution of an evolution variational inequality with a nonlocal space operator

Science.gov (United States)

Glazyrina, O. V.; Pavlova, M. F.

2016-11-01

We consider the parabolic inequality with monotone with respect to a gradient space operator, which is depended on integral with respect to space variables solution characteristic. We construct a two-layer differential scheme for this problem with use of penalty method, semidiscretization with respect to time variable method and the finite element method (FEM) with respect to space variables. We proved a convergence of constructed mothod.

Hybrid Iterative Scheme for Triple Hierarchical Variational Inequalities with Mixed Equilibrium, Variational Inclusion, and Minimization Constraints

Directory of Open Access Journals (Sweden)

Lu-Chuan Ceng

2014-01-01

Full Text Available We introduce and analyze a hybrid iterative algorithm by combining Korpelevich's extragradient method, the hybrid steepest-descent method, and the averaged mapping approach to the gradient-projection algorithm. It is proven that, under appropriate assumptions, the proposed algorithm converges strongly to a common element of the fixed point set of finitely many nonexpansive mappings, the solution set of a generalized mixed equilibrium problem (GMEP, the solution set of finitely many variational inclusions, and the solution set of a convex minimization problem (CMP, which is also a unique solution of a triple hierarchical variational inequality (THVI in a real Hilbert space. In addition, we also consider the application of the proposed algorithm to solving a hierarchical variational inequality problem with constraints of the GMEP, the CMP, and finitely many variational inclusions.

Efficient algorithm for bifurcation problems of variational inequalities

International Nuclear Information System (INIS)

Mittelmann, H.D.

1983-01-01

For a class of variational inequalities on a Hilbert space H bifurcating solutions exist and may be characterized as critical points of a functional with respect to the intersection of the level surfaces of another functional and a closed convex subset K of H. In a recent paper [13] we have used a gradient-projection type algorithm to obtain the solutions for discretizations of the variational inequalities. A related but Newton-based method is given here. Global and asymptotically quadratic convergence is proved. Numerical results show that it may be used very efficiently in following the bifurcating branches and that is compares favorably with several other algorithms. The method is also attractive for a class of nonlinear eigenvalue problems (K = H) for which it reduces to a generalized Rayleigh-quotient interaction. So some results are included for the path following in turning-point problems

Some Implicit Methods for Solving Harmonic Variational Inequalities

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Muhammad Aslam Noor

2016-08-01

Full Text Available In this paper, we use the auxiliary principle technique to suggest an implicit method for solving the harmonic variational inequalities. It is shown that the convergence of the proposed method only needs pseudo monotonicity of the operator, which is a weaker condition than monotonicity.

Advances in variational and hemivariational inequalities theory, numerical analysis, and applications

CERN Document Server

Migórski, Stanisław; Sofonea, Mircea

2015-01-01

Highlighting recent advances in variational and hemivariational inequalities with an emphasis on theory, numerical analysis and applications, this volume serves as an indispensable resource to graduate students and researchers interested in the latest results from recognized scholars in this relatively young and rapidly-growing field. Particularly, readers will find that the volume’s results and analysis present valuable insights into the fields of pure and applied mathematics, as well as civil, aeronautical, and mechanical engineering. Researchers and students will find new results on well posedness to stationary and evolutionary inequalities and their rigorous proofs. In addition to results on modeling and abstract problems, the book contains new results on the numerical methods for variational and hemivariational inequalities. Finally, the applications presented illustrate the use of these results in the study of miscellaneous mathematical models which describe the contact between deformable bodies and a...

Gradient-type methods in inverse parabolic problems

International Nuclear Information System (INIS)

Kabanikhin, Sergey; Penenko, Aleksey

2008-01-01

This article is devoted to gradient-based methods for inverse parabolic problems. In the first part, we present a priori convergence theorems based on the conditional stability estimates for linear inverse problems. These theorems are applied to backwards parabolic problem and sideways parabolic problem. The convergence conditions obtained coincide with sourcewise representability in the self-adjoint backwards parabolic case but they differ in the sideways case. In the second part, a variational approach is formulated for a coefficient identification problem. Using adjoint equations, a formal gradient of an objective functional is constructed. A numerical test illustrates the performance of conjugate gradient algorithm with the formal gradient.

Smooth bifurcation for variational inequalities based on Lagrange multipliers

Czech Academy of Sciences Publication Activity Database

Eisner, Jan; Kučera, Milan; Recke, L.

2006-01-01

Roč. 19, č. 9 (2006), s. 981-1000 ISSN 0893-4983 R&D Projects: GA AV ČR(CZ) IAA100190506 Institutional research plan: CEZ:AV0Z10190503 Keywords : abstract variational inequality * bifurcation * Lagrange multipliers Subject RIV: BA - General Mathematics

A unified framework of descent algorithms for nonlinear programs and variational inequalities

International Nuclear Information System (INIS)

Patriksson, M.

1993-01-01

We present a framework of algorithms for the solution of continuous optimization and variational inequality problems. In the general algorithm, a search direction finding auxiliary problems is obtained by replacing the original cost function with an approximating monotone cost function. The proposed framework encompasses algorithm classes presented earlier by Cohen, Dafermos, Migdalas, and Tseng, and includes numerous descent and successive approximation type methods, such as Newton methods, Jacobi and Gauss-Siedel type decomposition methods for problems defined over Cartesian product sets, and proximal point methods, among others. The auxiliary problem of the general algorithm also induces equivalent optimization reformulation and descent methods for asymmetric variational inequalities. We study the convergence properties of the general algorithm when applied to unconstrained optimization, nondifferentiable optimization, constrained differentiable optimization, and variational inequalities; the emphasis of the convergence analyses is placed on basic convergence results, convergence using different line search strategies and truncated subproblem solutions, and convergence rate results. This analysis offer a unification of known results; moreover, it provides strengthenings of convergence results for many existing algorithms, and indicates possible improvements of their realizations. 482 refs

Studies with Parabolic Parabolic Linear Parabolic (PPLP) momentum function in the LHC

CERN Document Server

Solfaroli Camillocci, Matteo; Timko, Helga; Wenninger, Jorg; CERN. Geneva. ATS Department

2018-01-01

Measurements performed with a Parabolic Parabolic Linear Parabolic (PPLP) momentum function in the LHC. Three attempts have been performed with a pilot bunch and one with nominal bunch (1.1x1011 p/bunch).

A recurrent neural network based on projection operator for extended general variational inequalities.

Science.gov (United States)

Liu, Qingshan; Cao, Jinde

2010-06-01

Based on the projection operator, a recurrent neural network is proposed for solving extended general variational inequalities (EGVIs). Sufficient conditions are provided to ensure the global convergence of the proposed neural network based on Lyapunov methods. Compared with the existing neural networks for variational inequalities, the proposed neural network is a modified version of the general projection neural network existing in the literature and capable of solving the EGVI problems. In addition, simulation results on numerical examples show the effectiveness and performance of the proposed neural network.

Solving Quasi-Variational Inequalities for Image Restoration with Adaptive Constraint Sets

KAUST Repository

Lenzen, F.; Lellmann, J.; Becker, F.; Schnö rr, C.

2014-01-01

© 2014 Society for Industrial and Applied Mathematics. We consider a class of quasi-variational inequalities (QVIs) for adaptive image restoration, where the adaptivity is described via solution-dependent constraint sets. In previous work we studied

Semistability of first-order evolution variational inequalities

Directory of Open Access Journals (Sweden)

Hassan Saoud

2015-10-01

Full Text Available Semistability is the property whereby the solutions of a dynamical system converge to a Lyapunov stable equilibrium point determined by the system initial conditions. We extend the theory of semistability to a class of first-order evolution variational inequalities, and study the finite-time semistability. These results are Lyapunov-based and are obtained without any assumptions of sign definiteness on the Lyapunov function. Our results are supported by some examples from unilateral mechanics and electrical circuits involving nonsmooth elements such as Coulomb's friction forces and diodes.

Do racial inequities in infant mortality correspond to variations in societal conditions? A study of state-level income inequality in the U.S., 1992-2007.

Science.gov (United States)

Siddiqi, Arjumand; Jones, Marcella K; Bruce, Donald J; Erwin, Paul C

2016-09-01

Prior studies have examined the association between income inequality and overall infant mortality rates (IMR). We examine effects of income inequality on racial inequities in IMR over the period 1992-2007 in the U.S. Race-specific state IMR data were obtained from 1992 to 2007, from which absolute and relative IMR inequities were calculated. Fixed and random effects models, adjusted for state-level median income, percent poverty, percent high school graduates, and unemployment rate, were used to determine contemporaneous and lagged state-level associations between income inequality and racial IMR inequities. Racial IMR inequities varied significantly across the U.S. Contemporaneous income inequality was negatively associated with white IMR only. Two-year lagged income inequality was negatively associated with black IMR and had the most pronounced effect on racial inequities in IMR. Future studies should consider lagged effects of income inequality on IMR and other health outcomes, and should examine other potential societal conditions that may account for state-level variations in racial IMR inequities. Copyright © 2016 Elsevier Ltd. All rights reserved.

A variational approach to Lyapunov type inequalities from ODEs to PDEs

CERN Document Server

Cañada, Antonio

2015-01-01

This book highlights the current state of Lyapunov-type inequalities through a detailed analysis. Aimed toward researchers and students working in differential equations and those interested in the applications of stability theory and resonant systems, the book begins with an overview Lyapunov’s original results and moves forward to include prevalent results obtained in the past ten years. Detailed proofs and an emphasis on basic ideas are provided for different boundary conditions for ordinary differential equations, including Neumann, Dirichlet, periodic, and antiperiodic conditions. Novel results of higher eigenvalues, systems of equations, partial differential equations as well as variational approaches are presented. To this respect, a new and unified variational point of view  is introduced for the treatment of such problems and a systematic discussion of different types of boundary conditions is featured. Various problems make the study of Lyapunov-type inequalities of interest to those in pure and ...

Photoionization cross section in a spherical quantum dot: Effects of some parabolic confining electric potentials

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M. Tshipa

2017-12-01

Full Text Available A theoretical investigation of the effects of spatial variation of confining electric potential on photoionization cross section (PCS in a spherical quantum dot is presented. The potential profiles considered here are the shifted parabolic potential and the inverse lateral shifted parabolic potential compared with the well-studied parabolic potential. The primary findings are that parabolic potential and the inverse lateral shifted parabolic potential blue shift the peaks of the PCS while the shifted parabolic potential causes a red shift.

Inverse source problem and null controllability for multidimensional parabolic operators of Grushin type

International Nuclear Information System (INIS)

Beauchard, K; Cannarsa, P; Yamamoto, M

2014-01-01

The approach to Lipschitz stability for uniformly parabolic equations introduced by Imanuvilov and Yamamoto in 1998 based on Carleman estimates, seems hard to apply to the case of Grushin-type operators of interest to this paper. Indeed, such estimates are still missing for parabolic operators degenerating in the interior of the space domain. Nevertheless, we are able to prove Lipschitz stability results for inverse source problems for such operators, with locally distributed measurements in an arbitrary space dimension. For this purpose, we follow a mixed strategy which combines the approach due to Lebeau and Robbiano, relying on Fourier decomposition and Carleman inequalities for heat equations with non-smooth coefficients (solved by the Fourier modes). As a corollary, we obtain a direct proof of the observability of multidimensional Grushin-type parabolic equations, with locally distributed observations—which is equivalent to null controllability with locally distributed controls. (paper)

On T-solutions of degenerate anisotropic elliptic variational inequalities with L1-data

International Nuclear Information System (INIS)

Kovalevsky, Alexander A; Gorban, Yuliya S

2011-01-01

We introduce the notions of T-solutions and shift T-solutions of variational inequalities corresponding to a non-linear degenerate anisotropic elliptic operator, a constraint set in a sufficiently large class, and an L 1 -right-hand side. We prove theorems on the existence and uniqueness of such solutions and describe their properties. While the notion of T-solution is defined only when the constraint set contains at least one bounded function, the notion of shift T-solution does not require this condition. We describe the relation between these notions and prove that these types of solutions of a variational inequality coincide with ordinary solutions whenever the right-hand side is sufficiently regular.

Evolution Inclusions and Variation Inequalities for Earth Data Processing II Differential-operator Inclusions and Evolution Variation Inequalities for Earth Data Processing

CERN Document Server

Zgurovsky, Mikhail Z; Kasyanov, Pavlo O

2011-01-01

Here, the authors present modern mathematical methods to solve problems of differential-operator inclusions and evolution variation inequalities which may occur in fields such as geophysics, aerohydrodynamics, or fluid dynamics. For the first time, they describe the detailed generalization of various approaches to the analysis of fundamentally nonlinear models and provide a toolbox of mathematical equations. These new mathematical methods can be applied to a broad spectrum of problems. Examples of these are phase changes, diffusion of electromagnetic, acoustic, vibro-, hydro- and seismoacousti

Equilibrium models and variational inequalities

CERN Document Server

Konnov, Igor

2007-01-01

The concept of equilibrium plays a central role in various applied sciences, such as physics (especially, mechanics), economics, engineering, transportation, sociology, chemistry, biology and other fields. If one can formulate the equilibrium problem in the form of a mathematical model, solutions of the corresponding problem can be used for forecasting the future behavior of very complex systems and, also, for correcting the the current state of the system under control. This book presents a unifying look on different equilibrium concepts in economics, including several models from related sciences.- Presents a unifying look on different equilibrium concepts and also the present state of investigations in this field- Describes static and dynamic input-output models, Walras, Cassel-Wald, spatial price, auction market, oligopolistic equilibrium models, transportation and migration equilibrium models- Covers the basics of theory and solution methods both for the complementarity and variational inequality probl...

A Priori Regularity of Parabolic Partial Differential Equations

KAUST Repository

Berkemeier, Francisco

2018-05-13

In this thesis, we consider parabolic partial differential equations such as the heat equation, the Fokker-Planck equation, and the porous media equation. Our aim is to develop methods that provide a priori estimates for solutions with singular initial data. These estimates are obtained by understanding the time decay of norms of solutions. First, we derive regularity results for the heat equation by estimating the decay of Lebesgue norms. Then, we apply similar methods to the Fokker-Planck equation with suitable assumptions on the advection and diffusion. Finally, we conclude by extending our techniques to the porous media equation. The sharpness of our results is confirmed by examining known solutions of these equations. The main contribution of this thesis is the use of functional inequalities to express decay of norms as differential inequalities. These are then combined with ODE methods to deduce estimates for the norms of solutions and their derivatives.

A frictional contact problem with wear involving elastic-viscoplastic materials with damage and thermal effects

Directory of Open Access Journals (Sweden)

Abdelmoumene Djabi

2015-05-01

Full Text Available We consider a mathematical problem for quasistatic contact between a thermo-elastic-viscoplastic body with damage and an obstacle. The contact is frictional and bilateral with a moving rigid foundation which results in the wear of the contacting surface. We employ the thermo-elasticviscoplastic with damage constitutive law for the material. The damage of the material caused by elastic deformations. The evolution of the damage is described by an inclusion of parabolic type. The problem is formulated as a coupled system of an elliptic variational inequality for the displacement, a parabolic variational inequality for the damage and the heat equation for the temperature. We establish a variational formulation for the model and we prove the existence of a unique weak solution to the problem. The proof is based on a classical existence and uniqueness result on parabolic inequalities, differential equations and fixed point arguments.

Parabolic approximation method for fast magnetosonic wave propagation in tokamaks

International Nuclear Information System (INIS)

Phillips, C.K.; Perkins, F.W.; Hwang, D.Q.

1985-07-01

Fast magnetosonic wave propagation in a cylindrical tokamak model is studied using a parabolic approximation method in which poloidal variations of the wave field are considered weak in comparison to the radial variations. Diffraction effects, which are ignored by ray tracing mthods, are included self-consistently using the parabolic method since continuous representations for the wave electromagnetic fields are computed directly. Numerical results are presented which illustrate the cylindrical convergence of the launched waves into a diffraction-limited focal spot on the cyclotron absorption layer near the magnetic axis for a wide range of plasma confinement parameters

On Ostrowski Type Inequalities for Functions of Two Variables with Bounded Variation

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Hüseyin Budak

2016-10-01

Full Text Available In this paper, we establish a new generalization of Ostrowski type inequalities for functions of two independent variables with bounded variation and apply it for qubature formulae. Some connections with the rectangle, the midpoint and Simpson's rule are also given.

Systems of general nonlinear set-valued mixed variational inequalities problems in Hilbert spaces

Directory of Open Access Journals (Sweden)

Cho Yeol

2011-01-01

Full Text Available Abstract In this paper, the existing theorems and methods for finding solutions of systems of general nonlinear set-valued mixed variational inequalities problems in Hilbert spaces are studied. To overcome the difficulties, due to the presence of a proper convex lower semi-continuous function, φ and a mapping g, which appeared in the considered problem, we have used some applications of the resolvent operator technique. We would like to point out that although many authors have proved results for finding solutions of the systems of nonlinear set-valued (mixed variational inequalities problems, it is clear that it cannot be directly applied to the problems that we have considered in this paper because of φ and g. 2000 AMS Subject Classification: 47H05; 47H09; 47J25; 65J15.

Temperature Performance Evaluation of Parabolic Dishes Covered ...

African Journals Online (AJOL)

Aweda

The parabolic dish with glass material gave the highest temperature of .... 3: Second day variation temperature and time using different materials. 8. 10 .... the sun rays at that particular time. ... especially between 11:00 am and 3:00 pm when.

Optimal control of ODE systems involving a rate independent variational inequality

Czech Academy of Sciences Publication Activity Database

Brokate, M.; Krejčí, Pavel

2013-01-01

Roč. 18, č. 2 (2013), s. 331-348 ISSN 1531-3492 R&D Projects: GA ČR GAP201/10/2315 Institutional support: RVO:67985840 Keywords : evolution variational inequalities * hysteresis * optimal control Subject RIV: BA - General Mathematics Impact factor: 0.628, year: 2013 http://www.aimsciences.org/journals/displayArticlesnew.jsp?paperID=7971

Non-compact random generalized games and random quasi-variational inequalities

OpenAIRE

Yuan, Xian-Zhi

1994-01-01

In this paper, existence theorems of random maximal elements, random equilibria for the random one-person game and random generalized game with a countable number of players are given as applications of random fixed point theorems. By employing existence theorems of random generalized games, we deduce the existence of solutions for non-compact random quasi-variational inequalities. These in turn are used to establish several existence theorems of noncompact generalized random ...

Convergence Properties of Projection and Contraction Methods for Variational Inequality Problems

International Nuclear Information System (INIS)

Xiu, N.; Wang, C.; Zhang, J.

2001-01-01

In this paper we develop the convergence theory of a general class of projection and contraction algorithms (PC method), where an extended stepsize rule is used, for solving variational inequality (VI) problems. It is shown that, by defining a scaled projection residue, the PC method forces the sequence of the residues to zero. It is also shown that, by defining a projected function, the PC method forces the sequence of projected functions to zero. A consequence of this result is that if the PC method converges to a nondegenerate solution of the VI problem, then after a finite number of iterations, the optimal face is identified. Finally, we study local convergence behavior of the extragradient algorithm for solving the KKT system of the inequality constrained VI problem

Bifurcation direction and exchange of stability for variational inequalities on nonconvex sets

Czech Academy of Sciences Publication Activity Database

Eisner, Jan; Kučera, Milan; Recke, L.

2007-01-01

Roč. 67, č. 5 (2007), s. 1082-1101 ISSN 0362-546X R&D Projects: GA AV ČR IAA100190506 Institutional research plan: CEZ:AV0Z10190503 Keywords : multiparameter variational inequality * direction of bifurcation * stability of bifurcating solutions Subject RIV: BA - General Mathematics Impact factor: 1.097, year: 2007

Fast solution of Cahn–Hilliard variational inequalities using implicit time discretization and finite elements

KAUST Repository

Bosch, Jessica; Stoll, Martin; Benner, Peter

2014-01-01

We consider the efficient solution of the Cahn-Hilliard variational inequality using an implicit time discretization, which is formulated as an optimal control problem with pointwise constraints on the control. By applying a semi-smooth Newton

Existence of solutions to nonlinear parabolic unilateral problems with an obstacle depending on time

Directory of Open Access Journals (Sweden)

Nabila Bellal

2014-10-01

Full Text Available Using the penalty method, we prove the existence of solutions to nonlinear parabolic unilateral problems with an obstacle depending on time. To find a solution, the original inequality is transformed into an equality by adding a positive function on the right-hand side and a complementary condition. This result can be seen as a generalization of the results by Mokrane in [11] where the obstacle is zero.

Social inequality in infant mortality: what explains variation across low and middle income countries?

Science.gov (United States)

Hajizadeh, Mohammad; Nandi, Arijit; Heymann, Jody

2014-01-01

Growing work demonstrates social gradients in infant mortality within countries. However, few studies have compared the magnitude of these inequalities cross-nationally. Even fewer have assessed the determinants of social inequalities in infant mortality across countries. This study provides a comprehensive and comparative analysis of social inequalities in infant mortality in 53 low-and-middle-income countries (LMICs). We used the most recent nationally representative household samples (n = 874,207) collected through the Demographic Health Surveys (DHS) to calculate rates of infant mortality. The relative and absolute concentration indices were used to quantify social inequalities in infant mortality. Additionally, we used meta-regression analyses to examine whether levels of inequality in proximate determinants of infant mortality were associated with social inequalities in infant mortality across countries. Estimates of both the relative and the absolute concentration indices showed a substantial variation in social inequalities in infant mortality among LMICs. Meta-regression analyses showed that, across countries, the relative concentration of teenage pregnancy among poorer households was positively associated with the relative concentration of infant mortality among these groups (beta = 0.333, 95% CI = 0.115 0.551). Our results demonstrate that the concentration of infant deaths among socioeconomically disadvantaged households in the majority of LMICs remains an important health and social policy concern. The findings suggest that policies designed to reduce the concentration of teenage pregnancy among mothers in lower socioeconomic groups may mitigate social inequalities in infant mortality. Copyright © 2013 Elsevier Ltd. All rights reserved.

Global variations in health: evaluating Wilkinson's income inequality hypothesis using the World Values Survey.

Science.gov (United States)

Jen, Min Hua; Jones, Kelvyn; Johnston, Ron

2009-02-01

This international comparative study analyses individual-level data derived from the World Values Survey to evaluate Wilkinson's [(1996). Unhealthy societies: The afflictions of inequality. London: Routledge; (1998). Mortality and distribution of income. Low relative income affects mortality [letter; comment]. British Medical Journal, 316, 1611-1612] income inequality hypothesis regarding variations in health status. Random-coefficient, multilevel modelling provides a direct test of Wilkinson's hypothesis using micro-data on individuals and macro-data on income inequalities analysed simultaneously. This overcomes the ecological fallacy that has troubled previous research into links between individual self-rated health, individual income, country income and income inequality data. Logic regression analysis reveals that there are substantial differences between countries in self-rated health after taking account of age and gender, and individual income has a clear effect in that poorer people report experiencing worse health. The Wilkinson hypothesis is not supported, however, since there is no significant relationship between health and income inequality when individual factors are taken into account. Substantial differences between countries remain even after taking account of micro- and macro-variables; in particular the former communist countries report high levels of poor health.

On an Optimal -Control Problem in Coefficients for Linear Elliptic Variational Inequality

Directory of Open Access Journals (Sweden)

Olha P. Kupenko

2013-01-01

Full Text Available We consider optimal control problems for linear degenerate elliptic variational inequalities with homogeneous Dirichlet boundary conditions. We take the matrix-valued coefficients in the main part of the elliptic operator as controls in . Since the eigenvalues of such matrices may vanish and be unbounded in , it leads to the “noncoercivity trouble.” Using the concept of convergence in variable spaces and following the direct method in the calculus of variations, we establish the solvability of the optimal control problem in the class of the so-called -admissible solutions.

Cross-Country Variation in Adult Skills Inequality: Why Are Skill Levels and Opportunities so Unequal in Anglophone Countries?

Science.gov (United States)

Green, Andy; Green, Francis; Pensiero, Nicola

2015-01-01

This article examines cross-country variations in adult skills inequality and asks why skills in Anglophone countries are so unequal. Drawing on the Organization for Economic Cooperation and Development's recent Survey of Adult Skills and other surveys, it investigates the differences across countries and country groups in inequality in both…

Global Inequality

DEFF Research Database (Denmark)

Niño-Zarazúa, Miguel; Roope, Laurence; Tarp, Finn

2017-01-01

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...... by centrist measures such as the Krtscha, could return to 1975 levels, at today's domestic and global per capita income levels, but this would require quite dramatic structural reforms to reduce domestic inequality levels in most countries....... 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...

Semi-Coercive Variational Inequalities with Uncertain Input Data. Applications to Shaloow Shells

Czech Academy of Sciences Publication Activity Database

Hlaváček, Ivan; Lovíšek, J.

2005-01-01

Roč. 15, č. 2 (2005), s. 273-299 ISSN 0218-2025 R&D Projects: GA ČR(CZ) GA201/01/1200; GA ČR(CZ) GA201/02/1058 Institutional research plan: CEZ:AV0Z10190503 Keywords : control of variational inequalities * uncertain input data * shallow elastic shells Subject RIV: BA - General Mathematics Impact factor: 1.248, year: 2005

Global Inequality

DEFF Research Database (Denmark)

Niño-Zarazúa, Miguel; Roope, Laurence; Tarp, Finn

2017-01-01

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...

Nonlinearly preconditioned semismooth Newton methods for variational inequality solution of two-phase flow in porous media

KAUST Repository

Yang, Haijian

2016-12-10

Most existing methods for solving two-phase flow problems in porous media do not take the physically feasible saturation fractions between 0 and 1 into account, which often destroys the numerical accuracy and physical interpretability of the simulation. To calculate the solution without the loss of this basic requirement, we introduce a variational inequality formulation of the saturation equilibrium with a box inequality constraint, and use a conservative finite element method for the spatial discretization and a backward differentiation formula with adaptive time stepping for the temporal integration. The resulting variational inequality system at each time step is solved by using a semismooth Newton algorithm. To accelerate the Newton convergence and improve the robustness, we employ a family of adaptive nonlinear elimination methods as a nonlinear preconditioner. Some numerical results are presented to demonstrate the robustness and efficiency of the proposed algorithm. A comparison is also included to show the superiority of the proposed fully implicit approach over the classical IMplicit Pressure-Explicit Saturation (IMPES) method in terms of the time step size and the total execution time measured on a parallel computer.

Nonlinearly preconditioned semismooth Newton methods for variational inequality solution of two-phase flow in porous media

KAUST Repository

Yang, Haijian; Sun, Shuyu; Yang, Chao

2016-01-01

Most existing methods for solving two-phase flow problems in porous media do not take the physically feasible saturation fractions between 0 and 1 into account, which often destroys the numerical accuracy and physical interpretability of the simulation. To calculate the solution without the loss of this basic requirement, we introduce a variational inequality formulation of the saturation equilibrium with a box inequality constraint, and use a conservative finite element method for the spatial discretization and a backward differentiation formula with adaptive time stepping for the temporal integration. The resulting variational inequality system at each time step is solved by using a semismooth Newton algorithm. To accelerate the Newton convergence and improve the robustness, we employ a family of adaptive nonlinear elimination methods as a nonlinear preconditioner. Some numerical results are presented to demonstrate the robustness and efficiency of the proposed algorithm. A comparison is also included to show the superiority of the proposed fully implicit approach over the classical IMplicit Pressure-Explicit Saturation (IMPES) method in terms of the time step size and the total execution time measured on a parallel computer.

Hydrostatic pressure and conduction band non-parabolicity effects on the impurity binding energy in a spherical quantum dot

International Nuclear Information System (INIS)

Sivakami, A.; Mahendran, M.

2010-01-01

The binding energy of a shallow hydrogenic impurity in a spherical quantum dot under hydrostatic pressure with square well potential is calculated using a variational approach within the effective mass approximation. The effect of conduction band non-parabolicity on these energies is also estimated. The binding energy is computed for GaAs spherical quantum dot as a function of dot size, hydrostatic pressure both in the presence and absence of the band non-parabolicity effect. Our results show that (i) the hydrostatic pressure increases the impurity binding energy when dot radius increases for a given pressure, (ii) the hydrostatic pressure with the band non-parabolicity effect effectively increases the binding energy such that the variation is large for smaller dots and (iii) the maximum contribution by the non-parabolicity effect is about 15% for narrow dots. Our results are in good agreement with Perez-Merchancano et al. [J. Phys. Condens. Matter 19 (2007) 026225] who have not considered the conduction band non-parabolicity effect.

From the Triangle Inequality to the Isoperimetric Inequality

Indian Academy of Sciences (India)

IAS Admin

Calculus of variations, shape optimization, isoperimetric prob- lems. Figure 1. Starting from the triangle inequality, we will dis- cuss a series of shape optimization problems us- ing elementary geometry and ultimately derive the classical isoperimetric inequality in the plane. One of the important results we learn in plane geom ...

Nonlinear Eigenvalue Problems in Elliptic Variational Inequalities: a local study

International Nuclear Information System (INIS)

Conrad, F.; Brauner, C.; Issard-Roch, F.; Nicolaenko, B.

1985-01-01

The authors consider a class of Nonlinear Eigenvalue Problems (N.L.E.P.) associated with Elliptic Variational Inequalities (E.V.I.). First the authors introduce the main tools for a local study of branches of solutions; the authors extend the linearization process required in the case of equations. Next the authors prove the existence of arcs of solutions close to regular vs singular points, and determine their local behavior up to the first order. Finally, the authors discuss the connection between their regularity condition and some stability concept. 37 references, 6 figures

Preconditioning for Allen–Cahn variational inequalities with non-local constraints

KAUST Repository

Blank, Luise

2012-06-01

The solution of Allen-Cahn variational inequalities with mass constraints is of interest in many applications. This problem can be solved both in its scalar and vector-valued form as a PDE-constrained optimization problem by means of a primal-dual active set method. At the heart of this method lies the solution of linear systems in saddle point form. In this paper we propose the use of Krylov-subspace solvers and suitable preconditioners for the saddle point systems. Numerical results illustrate the competitiveness of this approach. © 2012 Elsevier Inc.

A neural network method for solving a system of linear variational inequalities

International Nuclear Information System (INIS)

Lan Hengyou; Cui Yishun

2009-01-01

In this paper, we transmute the solution for a new system of linear variational inequalities to an equilibrium point of neural networks, and by using analytic technique, some sufficient conditions are presented. Further, the estimation of the exponential convergence rates of the neural networks is investigated. The new and useful results obtained in this paper generalize and improve the corresponding results of recent works.

Maximum principles and sharp constants for solutions of elliptic and parabolic systems

CERN Document Server

Kresin, Gershon

2012-01-01

The main goal of this book is to present results pertaining to various versions of the maximum principle for elliptic and parabolic systems of arbitrary order. In particular, the authors present necessary and sufficient conditions for validity of the classical maximum modulus principles for systems of second order and obtain sharp constants in inequalities of Miranda-Agmon type and in many other inequalities of a similar nature. Somewhat related to this topic are explicit formulas for the norms and the essential norms of boundary integral operators. The proofs are based on a unified approach using, on one hand, representations of the norms of matrix-valued integral operators whose target spaces are linear and finite dimensional, and, on the other hand, on solving certain finite dimensional optimization problems. This book reflects results obtained by the authors, and can be useful to research mathematicians and graduate students interested in partial differential equations.

Carleman estimates, observability inequalities and null controllability for interior degenerate nonsmooth parabolic equations

CERN Document Server

Fragnelli, Genni

2016-01-01

The authors consider a parabolic problem with degeneracy in the interior of the spatial domain, and they focus on observability results through Carleman estimates for the associated adjoint problem. The novelties of the present paper are two. First, the coefficient of the leading operator only belongs to a Sobolev space. Second, the degeneracy point is allowed to lie even in the interior of the control region, so that no previous result can be adapted to this situation; however, different cases can be handled, and new controllability results are established as a consequence.

Approximation of Fixed Points of Nonexpansive Mappings and Solutions of Variational Inequalities

Directory of Open Access Journals (Sweden)

Chidume CO

2008-01-01

Full Text Available Abstract Let be a real -uniformly smooth Banach space with constant , . Let and be a nonexpansive map and an -strongly accretive map which is also -Lipschitzian, respectively. Let be a real sequence in that satisfies the following condition: and . For and , define a sequence iteratively in by , , . Then, converges strongly to the unique solution of the variational inequality problem (search for such that for all , where . A convergence theorem related to finite family of nonexpansive maps is also proved.

Proceedings (Mathematical Sciences) SUBJECT INDEX

Indian Academy of Sciences (India)

Variational formulae for Fuchsian groups over families of ... Nonlinear elliptic differential equations with multivalued ... delay differential equations. 351. Convolution ... Heisenberg's inequality. Uncertainty ... Parabolic bundles. Principal ...

Dynamic contact problem with adhesion and damage between thermo-electro-elasto-viscoplastic bodies

Science.gov (United States)

Hadj ammar, Tedjani; Saïdi, Abdelkader; Azeb Ahmed, Abdelaziz

2017-05-01

We study of a dynamic contact problem between two thermo-electro-elasto-viscoplastic bodies with damage and adhesion. The contact is frictionless and is modeled with normal compliance condition. We derive variational formulation for the model and prove an existence and uniqueness result of the weak solution. The proof is based on arguments of evolutionary variational inequalities, parabolic inequalities, differential equations, and fixed point theorem.

Strong Convergence Theorems for Variational Inequalities and Split Equality Problem

Directory of Open Access Journals (Sweden)

Yu Jing Wu

2013-01-01

Full Text Available Let H1, H2, and H3 be real Hilbert spaces, let C⊆H1, Q⊆H2 be two nonempty closed convex sets, and let A:H1→H3, B:H2→H3 be two bounded linear operators. The split equality problem (SEP is to find x∈C, y∈Q such that Ax=By. Let H=H1×H2; consider f:H→H a contraction with coefficient 00, and M:H→H is a β-inverse strongly monotone mapping. Let 0<γ<γ̅/α, S=C×Q and G:H→H3 be defined by restricting to H1 is A and restricting to H2 is -B, that is, G has the matrix form G=[A,-B]. It is proved that the sequence {wn}={(xn,yn}⊆H generated by the iterative method wn+1=PS[αnγf(wn+(I-αnTPS(I-γnG*GPS(wn-λnMwn] converges strongly to w̃ which solves the SEP and the following variational inequality: 〈(T-λfw̃,w-w̃〉≥0 and 〈Mw̃,w-w̃〉≥0 for all w∈S. Moreover, if we take M=G*G:H→H,  γn=0, then M is a β-inverse strongly monotone mapping, and the sequence {wn} generated by the iterative method wn+1=αnγf(wn+(I-αnTPS(wn-λnG*Gwn converges strongly to w̃ which solves the SEP and the following variational inequality: 〈(T-λfw̃,w-w̃〉≥0 for all w∈S.

Strong convergence with a modified iterative projection method for hierarchical fixed point problems and variational inequalities

Directory of Open Access Journals (Sweden)

Ibrahim Karahan

2016-04-01

Full Text Available Let C be a nonempty closed convex subset of a real Hilbert space H. Let {T_{n}}:C›H be a sequence of nearly nonexpansive mappings such that F:=?_{i=1}^{?}F(T_{i}?Ø. Let V:C›H be a ?-Lipschitzian mapping and F:C›H be a L-Lipschitzian and ?-strongly monotone operator. This paper deals with a modified iterative projection method for approximating a solution of the hierarchical fixed point problem. It is shown that under certain approximate assumptions on the operators and parameters, the modified iterative sequence {x_{n}} converges strongly to x^{*}?F which is also the unique solution of the following variational inequality: ?0, ?x?F. As a special case, this projection method can be used to find the minimum norm solution of above variational inequality; namely, the unique solution x^{*} to the quadratic minimization problem: x^{*}=argmin_{x?F}?x?². The results here improve and extend some recent corresponding results of other authors.

Functional inequalities

CERN Document Server

Ghoussoub, Nassif

2013-01-01

The book describes how functional inequalities are often manifestations of natural mathematical structures and physical phenomena, and how a few general principles validate large classes of analytic/geometric inequalities, old and new. This point of view leads to "systematic" approaches for proving the most basic inequalities, but also for improving them, and for devising new ones--sometimes at will and often on demand. These general principles also offer novel ways for estimating best constants and for deciding whether these are attained in appropriate function spaces. As such, improvements of Hardy and Hardy-Rellich type inequalities involving radially symmetric weights are variational manifestations of Sturm's theory on the oscillatory behavior of certain ordinary differential equations. On the other hand, most geometric inequalities, including those of Sobolev and Log-Sobolev type, are simply expressions of the convexity of certain free energy functionals along the geodesics on the Wasserstein manifold of...

Health Inequalities in Global Context

Science.gov (United States)

Beckfield, Jason; Olafsdottir, Sigrun

2017-01-01

The existence of social inequalities in health is well established. One strand of research focuses on inequalities in health within a single country. A separate and newer strand of research focuses on the relationship between inequality and average population health across countries. Despite the theorization of (presumably variable) social conditions as “fundamental causes” of disease and health, the cross-national literature has focused on average, aggregate population health as the central outcome. Controversies currently surround macro-structural determinants of overall population health such as income inequality. We advance and redirect these debates by conceptualizing inequalities in health as cross-national variables that are sensitive to social conditions. Using data from 48 World Values Survey countries, representing 74% of the world’s population, we examine cross-national variation in inequalities in health. The results reveal substantial variation in health inequalities according to income, education, sex, and migrant status. While higher socioeconomic position is associated with better self-rated health around the globe, the size of the association varies across institutional context, and across dimensions of stratification. There is some evidence that education and income are more strongly associated with self-rated health than sex or migrant status. PMID:29104292

An evolution infinity Laplace equation modelling dynamic elasto-plastic torsion

Science.gov (United States)

Messelmi, Farid

2017-12-01

We consider in this paper a parabolic partial differential equation involving the infinity Laplace operator and a Leray-Lions operator with no coercitive assumption. We prove the existence and uniqueness of the corresponding approached problem and we show that at the limit the solution solves the parabolic variational inequality arising in the elasto-plastic torsion problem.

A Penalization-Gradient Algorithm for Variational Inequalities

Directory of Open Access Journals (Sweden)

Abdellatif Moudafi

2011-01-01

Full Text Available This paper is concerned with the study of a penalization-gradient algorithm for solving variational inequalities, namely, find x̅∈C such that 〈Ax̅,y-x̅〉≥0 for all y∈C, where A:H→H is a single-valued operator, C is a closed convex set of a real Hilbert space H. Given Ψ:H→R  ∪  {+∞} which acts as a penalization function with respect to the constraint x̅∈C, and a penalization parameter βk, we consider an algorithm which alternates a proximal step with respect to ∂Ψ and a gradient step with respect to A and reads as xk=(I+λkβk∂Ψ-1(xk-1-λkAxk-1. Under mild hypotheses, we obtain weak convergence for an inverse strongly monotone operator and strong convergence for a Lipschitz continuous and strongly monotone operator. Applications to hierarchical minimization and fixed-point problems are also given and the multivalued case is reached by replacing the multivalued operator by its Yosida approximate which is always Lipschitz continuous.

A general product measurability theorem with applications to variational inequalities

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Kenneth L. Kuttler

2016-03-01

Full Text Available This work establishes the existence of measurable weak solutions to evolution problems with randomness by proving and applying a novel theorem on product measurability of limits of sequences of functions. The measurability theorem is used to show that many important existence theorems within the abstract theory of evolution inclusions or equations have straightforward generalizations to settings that include random processes or coefficients. Moreover, the convex set where the solutions are sought is not fixed but may depend on the random variables. The importance of adding randomness lies in the fact that real world processes invariably involve randomness and variability. Thus, this work expands substantially the range of applications of models with variational inequalities and differential set-inclusions.

Fixed point of the parabolic renormalization operator

CERN Document Server

Lanford III, Oscar E

2014-01-01

This monograph grew out of the authors' efforts to provide a natural geometric description for the class of maps invariant under parabolic renormalization and for the Inou-Shishikura fixed point itself as well as to carry out a computer-assisted study of the parabolic renormalization operator. It introduces a renormalization-invariant class of analytic maps with a maximal domain of analyticity and rigid covering properties and presents a numerical scheme for computing parabolic renormalization of a germ, which is used to compute the Inou-Shishikura renormalization fixed point.   Inside, readers will find a detailed introduction into the theory of parabolic bifurcation,  Fatou coordinates, Écalle-Voronin conjugacy invariants of parabolic germs, and the definition and basic properties of parabolic renormalization.   The systematic view of parabolic renormalization developed in the book and the numerical approach to its study will be interesting to both experts in the field as well as graduate students wishi...

On parabolic external maps

DEFF Research Database (Denmark)

Lomonaco, Luna; Petersen, Carsten Lunde; Shen, Weixiao

2017-01-01

We prove that any C1+BV degree d ≥ 2 circle covering h having all periodic orbits weakly expanding, is conjugate by a C1+BV diffeomorphism to a metrically expanding map. We use this to connect the space of parabolic external maps (coming from the theory of parabolic-like maps) to metrically expan...

Wage Inequality and the Location of Cities

DEFF Research Database (Denmark)

Farrokhi, Farid; Jinkins, David

agglomeration and congestion forces. The model bridges the gap between the spatial inequality literature which abstracts from geography, and the economic geography literature which abstracts from inequality. We find that geographical location explains 9.2% of observed variation in wage inequality across...

A Simply Constrained Optimization Reformulation of KKT Systems Arising from Variational Inequalities

International Nuclear Information System (INIS)

Facchinei, F.; Fischer, A.; Kanzow, C.; Peng, J.-M.

1999-01-01

The Karush-Kuhn-Tucker (KKT) conditions can be regarded as optimality conditions for both variational inequalities and constrained optimization problems. In order to overcome some drawbacks of recently proposed reformulations of KKT systems, we propose casting KKT systems as a minimization problem with nonnegativity constraints on some of the variables. We prove that, under fairly mild assumptions, every stationary point of this constrained minimization problem is a solution of the KKT conditions. Based on this reformulation, a new algorithm for the solution of the KKT conditions is suggested and shown to have some strong global and local convergence properties

A dynamic unilateral contact problem with adhesion and friction in viscoelasticity

Science.gov (United States)

Cocou, Marius; Schryve, Mathieu; Raous, Michel

2010-08-01

The aim of this paper is to study an interaction law coupling recoverable adhesion, friction and unilateral contact between two viscoelastic bodies of Kelvin-Voigt type. A dynamic contact problem with adhesion and nonlocal friction is considered and its variational formulation is written as the coupling between an implicit variational inequality and a parabolic variational inequality describing the evolution of the intensity of adhesion. The existence and approximation of variational solutions are analysed, based on a penalty method, some abstract results and compactness properties. Finally, some numerical examples are presented.

Dogs' reaction to inequity is affected by inhibitory control.

Science.gov (United States)

Brucks, Désirée; Range, Friederike; Marshall-Pescini, Sarah

2017-11-17

Inequity aversion is thought to act as a mechanism to ensure cooperation and has been studied in many different species, consistently revealing inter-individual variation. Inhibitory control has been proposed to act as one factor responsible for this variation since individuals need to inhibit performing the required action and/or refuse rewards in order to exhibit inequity aversion. Here, we investigated if dogs' sensitivity to inequity is affected by their capacity for inhibitory control, assessed in a test battery and questionnaire. Overall, dogs showing high compulsivity scores (i.e. repetitive behaviours independent of feedback) were more motivated to participate in the inequity task independent of the rewarding scheme. Dogs were more sensitive to inequity and individual contrast if they exhibited a slower decision speed in the inhibition tasks. Furthermore, less persistent and more impulsive dogs were more sensitive to reward inequity, potentially due to having a lower tolerance level for frustration. Results indicate that aspects of inhibitory control can explain the variation in dogs' inequity response, highlighting one of the mechanisms underlying responses to inequity. Emphasising the importance to design paradigms, which allow us to disentangle capacities to recognise inequity from the inability to react to it due to poor inhibitory control abilities.

Inequality and development

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Jovanović-Gavrilović Biljana D.

2003-01-01

Full Text Available Inequality can be analyzed from various aspects. In this paper our attention is drawn to economic inequality, most frequently manifested through income and wealth. The measurement of economic inequality is a complex task. The Lorenz curve and a number of numerical indices are applied, and let us mention the following ones: the Gini coefficient, the coefficient of variation, the Theil index and the Atkinson measure. These indices do satisfy the criteria (principles presenting, according to general consent an appropriate measure of economic inequality: anonymity (symmetry principle, population principle, relative income principle and the Dalton principle of transfer. In recent times, the problem of inequality has been attracting a lot of attention. The explanation should be sought in the widening of income differences (within individual countries and between them and also in new knowledge about the relationship between inequality and development. The attitude to inequality being determined mainly by the economic development level (as presented in the Kuznets hypothesis is gradually being replaced by the attitude to inequality being the determinant of income and its growth. Contrary to previous beliefs about the stronger income inequalities being favorable to the economic growth, more recent research has pointed to the fact that a more equal distribution of income through various channels, can possibly act as an efficient stimulus of growth.

Self-accelerating parabolic cylinder waves in 1-D

Energy Technology Data Exchange (ETDEWEB)

Yuce, C., E-mail: cyuce@anadolu.edu.tr

2016-11-25

Highlights: • We find a new class of self-accelerating waves. • We show that parabolic cylinder waves self-accelerates in a parabolic potential. • We discuss that truncated parabolic cylinder waves propagates large distance without almost being non-diffracted in free space. - Abstract: We introduce a new self-accelerating wave packet solution of the Schrodinger equation in one dimension. We obtain an exact analytical parabolic cylinder wave for the inverted harmonic potential. We show that truncated parabolic cylinder waves exhibits their accelerating feature.

Sparse Recovery via l1 and L1 Optimization

Science.gov (United States)

2014-11-01

of China 1.1 (Mar. 2013), pp. 79–105. [13] H. Brezis. “Solutions with compact sup- port of variational inequalities ”. In: Rus- sian Mathematical...Surveys 29.2 (Apr. 30, 1974), pp. 103–108. [14] H. Brezis and A. Friedman. “Estimates on the support of solutions of parabolic varia- tional inequalities ...ized inverse problems (e.g., total variation image reconstruction [4]) have made `1 optimization a central tool in data processing problems. As the

A parabolic model for dimple potentials

International Nuclear Information System (INIS)

Aydin, Melike Cibik; Uncu, Haydar; Deniz, Coskun

2013-01-01

We study the truncated parabolic function and demonstrate that it is a representation of the Dirac δ function. We also show that the truncated parabolic function, used as a potential in the Schrödinger equation, has the same bound state spectrum, tunneling and reflection amplitudes as the Dirac δ potential, as the width of the parabola approximates to zero. Dirac δ potential is used to model dimple potentials which are utilized to increase the phase-space density of a Bose–Einstein condensate in a harmonic trap. We show that a harmonic trap with a δ function at the origin is a limiting case of the harmonic trap with a symmetric truncated parabolic potential around the origin. Hence, the truncated parabolic is a better candidate for modeling the dimple potentials. (paper)

Effect of non-parabolicity on the binding energy of a hydrogenic donor in quantum well with a magnetic field

International Nuclear Information System (INIS)

Jayakumar, K.; Balasubramanian, S.; Tomak, M.

1985-08-01

A hydrogenic donor in a quantum well in the presence of a magnetic field perpendicular to the barrier is considered in the effective mass approximation. The non-parabolicity of the subband is included in the Hamiltonian by an energy-dependent effective mass. The donor binding energy is calculated variationally for different well widths and the effect of non-parabolicity is discussed in the light of recent experimental results. (author)

Non-local quasi-linear parabolic equations

International Nuclear Information System (INIS)

Amann, H

2005-01-01

This is a survey of the most common approaches to quasi-linear parabolic evolution equations, a discussion of their advantages and drawbacks, and a presentation of an entirely new approach based on maximal L p regularity. The general results here apply, above all, to parabolic initial-boundary value problems that are non-local in time. This is illustrated by indicating their relevance for quasi-linear parabolic equations with memory and, in particular, for time-regularized versions of the Perona-Malik equation of image processing

Existence of evolutionary variational solutions via the calculus of variations

Science.gov (United States)

Bögelein, Verena; Duzaar, Frank; Marcellini, Paolo

In this paper we introduce a purely variational approach to time dependent problems, yielding the existence of global parabolic minimizers, that is ∫0T ∫Ω [uṡ∂tφ+f(x,Du)] dx dt⩽∫0T ∫Ω f(x,Du+Dφ) dx dt, whenever T>0 and φ∈C0∞(Ω×(0,T),RN). For the integrand f:Ω×R→[0,∞] we merely assume convexity with respect to the gradient variable and coercivity. These evolutionary variational solutions are obtained as limits of maps depending on space and time minimizing certain convex variational functionals. In the simplest situation, with some growth conditions on f, the method provides the existence of global weak solutions to Cauchy-Dirichlet problems of parabolic systems of the type ∂tu-divDξf(x,Du)=0 in Ω×(0,∞).

Solving Quasi-Variational Inequalities for Image Restoration with Adaptive Constraint Sets

KAUST Repository

Lenzen, F.

2014-01-01

© 2014 Society for Industrial and Applied Mathematics. We consider a class of quasi-variational inequalities (QVIs) for adaptive image restoration, where the adaptivity is described via solution-dependent constraint sets. In previous work we studied both theoretical and numerical issues. While we were able to show the existence of solutions for a relatively broad class of problems, we encountered difficulties concerning uniqueness of the solution as well as convergence of existing algorithms for solving QVIs. In particular, it seemed that with increasing image size the growing condition number of the involved differential operator posed severe problems. In the present paper we prove uniqueness for a larger class of problems, particularly independent of the image size. Moreover, we provide a numerical algorithm with proved convergence. Experimental results support our theoretical findings.

Binding energy of impurity states in an inverse parabolic quantum well under magnetic field

International Nuclear Information System (INIS)

Kasapoglu, E.; Sari, H.; Soekmen, I.

2007-01-01

We have investigated the effects of the magnetic field which is directed perpendicular to the well on the binding energy of the hydrogenic impurities in an inverse parabolic quantum well (IPQW) with different widths as well as different Al concentrations at the well center. The Al concentration at the barriers was always x max =0.3. The calculations were performed within the effective mass approximation, using a variational method. We observe that IPQW structure turns into parabolic quantum well with the inversion effect of the magnetic field and donor impurity binding energy in IPQW strongly depends on the magnetic field, Al concentration at the well center and well dimensions

Multilevel survival analysis of health inequalities in life expectancy

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Merlo Juan

2009-08-01

Full Text Available Abstract Background The health status of individuals is determined by multiple factors operating at both micro and macro levels and the interactive effects of them. Measures of health inequalities should reflect such determinants explicitly through sources of levels and combining mean differences at group levels and the variation of individuals, for the benefits of decision making and intervention planning. Measures derived recently from marginal models such as beta-binomial and frailty survival, address this issue to some extent, but are limited in handling data with complex structures. Beta-binomial models were also limited in relation to measuring inequalities of life expectancy (LE directly. Methods We propose a multilevel survival model analysis that estimates life expectancy based on survival time with censored data. The model explicitly disentangles total health inequalities in terms of variance components of life expectancy compared to the source of variation at the level of individuals in households and parishes and so on, and estimates group differences of inequalities at the same time. Adjusted distributions of life expectancy by gender and by household socioeconomic level are calculated. Relative and absolute health inequality indices are derived based on model estimates. The model based analysis is illustrated on a large Swedish cohort of 22,680 men and 26,474 women aged 65–69 in 1970 and followed up for 30 years. Model based inequality measures are compared to the conventional calculations. Results Much variation of life expectancy is observed at individual and household levels. Contextual effects at Parish and Municipality level are negligible. Women have longer life expectancy than men and lower inequality. There is marked inequality by the level of household socioeconomic status measured by the median life expectancy in each socio-economic group and the variation in life expectancy within each group. Conclusion Multilevel

Experimental study on a parabolic concentrator assisted solar desalting system

International Nuclear Information System (INIS)

Arunkumar, T.; Denkenberger, David; Velraj, R.; Sathyamurthy, Ravishankar; Tanaka, Hiroshi; Vinothkumar, K.

2015-01-01

Highlights: • We optimized the augmentation of condense by enhanced desalination methodology. • Parabolic concentrator has been integrated with solar distillation systems. • We measured ambient together with solar radiation intensity. - Abstract: This paper presents a modification of parabolic concentrator (PC) – solar still with continuous water circulation using a storage tank to enhance the productivity. Four modes of operation were studied experimentally: (i) PC-solar still without top cover cooling; (ii) PC-solar still with top cover cooling, PC-solar still integrated with phase change material (PCM) without top cover cooling and PC-solar still integrated PCM with cooling. The experiments were carried out for the cooling water flow rates of 40 ml/min; 50 ml/min, 60 ml/min, 80 ml/min and 100 ml/min. Diurnal variations of water temperature (T_w), ambient air temperature (T_a), top cover temperature (T_o_c) and production rate are measured with frequent time intervals. Water cooling was not cost effective, but adding PCM was.

Projection scheme for a reflected stochastic heat equation with additive noise

Science.gov (United States)

Higa, Arturo Kohatsu; Pettersson, Roger

2005-02-01

We consider a projection scheme as a numerical solution of a reflected stochastic heat equation driven by a space-time white noise. Convergence is obtained via a discrete contraction principle and known convergence results for numerical solutions of parabolic variational inequalities.

Ground-state energy of an exciton-(LO) phonon system in a parabolic quantum well

Science.gov (United States)

Gerlach, B.; Wüsthoff, J.; Smondyrev, M. A.

1999-12-01

This paper presents a variational study of the ground-state energy of an exciton-(LO) phonon system, which is spatially confined to a quantum well. The exciton-phonon interaction is of Fröhlich type, the confinement potentials are assumed to be parabolic functions of the coordinates. Making use of functional integral techniques, the phonon part of the problem can be eliminated exactly, leading us to an effective two-particle system, which has the same spectral properties as the original one. Subsequently, Jensen's inequality is applied to obtain an upper bound on the ground-state energy. The main intention of this paper is to analyze the influence of the quantum-well-induced localization of the exciton on its ground-state energy (or its binding energy, respectively). To do so, we neglect any mismatch of the masses or the dielectric constants, but admit an arbitrary strength of the confinement potentials. Our approach allows for a smooth interpolation of the ultimate limits of vanishing and infinite confinement, corresponding to the cases of a free three-dimensional and a free two-dimensional exciton-phonon system. The interpolation formula for the ground-state energy bound corresponds to similar formulas for the free polaron or the free exciton-phonon system. These bounds in turn are known to compare favorably with all previous ones, which we are aware of.

Fast solution of Cahn–Hilliard variational inequalities using implicit time discretization and finite elements

KAUST Repository

Bosch, Jessica

2014-04-01

We consider the efficient solution of the Cahn-Hilliard variational inequality using an implicit time discretization, which is formulated as an optimal control problem with pointwise constraints on the control. By applying a semi-smooth Newton method combined with a Moreau-Yosida regularization technique for handling the control constraints we show superlinear convergence in function space. At the heart of this method lies the solution of large and sparse linear systems for which we propose the use of preconditioned Krylov subspace solvers using an effective Schur complement approximation. Numerical results illustrate the competitiveness of this approach. © 2014 Elsevier Inc.

Jensen's Inequality Predicts Effects of Environmental Variation

Science.gov (United States)

Jonathan J. Ruel; Matthew P. Ayres

1999-01-01

Many biologists now recognize that environmental variance can exert important effects on patterns and processes in nature that are independent of average conditions. Jenson's inequality is a mathematical proof that is seldom mentioned in the ecological literature but which provides a powerful tool for predicting some direct effects of environmental variance in...

Solar parabolic dish technology evaluation report

Science.gov (United States)

Lucas, J. W.

1984-01-01

The activities of the JPL Solar Thermal Power Systems Parabolic Dish Project for FY 1983 are summarized. Included are discussions on designs of module development including concentrator, receiver, and power conversion subsystems together with a separate discussion of field tests, Small Community Experiment system development, and tests at the Parabolic Dish Test Site.

Hybrid Proximal-Point Methods for Zeros of Maximal Monotone Operators, Variational Inequalities and Mixed Equilibrium Problems

Directory of Open Access Journals (Sweden)

Kriengsak Wattanawitoon

2011-01-01

Full Text Available We prove strong and weak convergence theorems of modified hybrid proximal-point algorithms for finding a common element of the zero point of a maximal monotone operator, the set of solutions of equilibrium problems, and the set of solution of the variational inequality operators of an inverse strongly monotone in a Banach space under different conditions. Moreover, applications to complementarity problems are given. Our results modify and improve the recently announced ones by Li and Song (2008 and many authors.

Local Geographic Variation of Public Services Inequality: Does the Neighborhood Scale Matter?

Science.gov (United States)

Wei, Chunzhu; Cabrera-Barona, Pablo; Blaschke, Thomas

2016-01-01

This study aims to explore the effect of the neighborhood scale when estimating public services inequality based on the aggregation of social, environmental, and health-related indicators. Inequality analyses were carried out at three neighborhood scales: the original census blocks and two aggregated neighborhood units generated by the spatial “k”luster analysis by the tree edge removal (SKATER) algorithm and the self-organizing map (SOM) algorithm. Then, we combined a set of health-related public services indicators with the geographically weighted principal components analyses (GWPCA) and the principal components analyses (PCA) to measure the public services inequality across all multi-scale neighborhood units. Finally, a statistical test was applied to evaluate the scale effects in inequality measurements by combining all available field survey data. We chose Quito as the case study area. All of the aggregated neighborhood units performed better than the original census blocks in terms of the social indicators extracted from a field survey. The SKATER and SOM algorithms can help to define the neighborhoods in inequality analyses. Moreover, GWPCA performs better than PCA in multivariate spatial inequality estimation. Understanding the scale effects is essential to sustain a social neighborhood organization, which, in turn, positively affects social determinants of public health and public quality of life. PMID:27706072

Frictional contact problems for electro-viscoelastic materials with long-term memory, damage, and adhesion

Directory of Open Access Journals (Sweden)

Tedjani Hadj Ammar

2014-10-01

Full Text Available We consider a quasistatic contact problem between two electro-viscoelastic bodies with long-term memory and damage. The contact is frictional and is modelled with a version of normal compliance condition and the associated Coulomb's law of friction in which the adhesion of contact surfaces is taken into account. We derive a variational formulation for the model and prove an existence and uniqueness result of the weak solution. The proof is based on arguments of evolutionary variational inequalities, a classical existence and uniqueness result on parabolic inequalities, and Banach fixed point theorem.

Parabolic features and the erosion rate on Venus

Science.gov (United States)

Strom, Robert G.

1993-01-01

The impact cratering record on Venus consists of 919 craters covering 98 percent of the surface. These craters are remarkably well preserved, and most show pristine structures including fresh ejecta blankets. Only 35 craters (3.8 percent) have had their ejecta blankets embayed by lava and most of these occur in the Atla-Beta Regio region; an area thought to be recently active. parabolic features are associated with 66 of the 919 craters. These craters range in size from 6 to 105 km diameter. The parabolic features are thought to be the result of the deposition of fine-grained ejecta by winds in the dense venusian atmosphere. The deposits cover about 9 percent of the surface and none appear to be embayed by younger volcanic materials. However, there appears to be a paucity of these deposits in the Atla-Beta Regio region, and this may be due to the more recent volcanism in this area of Venus. Since parabolic features are probably fine-grain, wind-deposited ejecta, then all impact craters on Venus probably had these deposits at some time in the past. The older deposits have probably been either eroded or buried by eolian processes. Therefore, the present population of these features is probably associated with the most recent impact craters on the planet. Furthermore, the size/frequency distribution of craters with parabolic features is virtually identical to that of the total crater population. This suggests that there has been little loss of small parabolic features compared to large ones, otherwise there should be a significant and systematic paucity of craters with parabolic features with decreasing size compared to the total crater population. Whatever is erasing the parabolic features apparently does so uniformly regardless of the areal extent of the deposit. The lifetime of parabolic features and the eolian erosion rate on Venus can be estimated from the average age of the surface and the present population of parabolic features.

Changes in income inequality and the health of immigrants

Science.gov (United States)

Hamilton, Tod G.; Kawachi, Ichiro

2016-01-01

Research suggests that income inequality is inversely associated with health. This association has been documented in studies that utilize variation in income inequality across countries or across time from a single country. The primary criticism of these approaches is their inability to account for potential confounders that are associated with income inequality. This paper uses variation in individual experiences of income inequality among immigrants within the United States (U.S.) to evaluate whether individuals who moved from countries with greater income inequality than the U.S. have better health than those who migrated from countries with less income in equality than the U.S. Utilizing individual-level (March Current Population Survey) and country-level data (the United Nations Human Development Reports), we show that among immigrants who have resided in the U.S. between 6 and 20 years, self-reported health is more favorable for the immigrants in the former category (i.e., greater income inequality) than those in the latter (i.e., lower income inequality). Results also show that self-reported health is better among immigrants from more developed countries and those who have more years of education, are male, and are married. PMID:23352417

International Workshop on Elliptic and Parabolic Equations

CERN Document Server

Schrohe, Elmar; Seiler, Jörg; Walker, Christoph

2015-01-01

This volume covers the latest research on elliptic and parabolic equations and originates from the international Workshop on Elliptic and Parabolic Equations, held September 10-12, 2013 at the Leibniz Universität Hannover. It represents a collection of refereed research papers and survey articles written by eminent scientist on advances in different fields of elliptic and parabolic partial differential equations, including singular Riemannian manifolds, spectral analysis on manifolds, nonlinear dispersive equations, Brownian motion and kernel estimates, Euler equations, porous medium type equations, pseudodifferential calculus, free boundary problems, and bifurcation analysis.

Generalized bi-quasi-variational inequalities for quasi-semi-monotone and bi-quasi-semi-monotone operators with applications in non-compact settings and minimization problems

Directory of Open Access Journals (Sweden)

Chowdhury Molhammad SR

2000-01-01

Full Text Available Results are obtained on existence theorems of generalized bi-quasi-variational inequalities for quasi-semi-monotone and bi-quasi-semi-monotone operators in both compact and non-compact settings. We shall use the concept of escaping sequences introduced by Border (Fixed Point Theorem with Applications to Economics and Game Theory, Cambridge University Press, Cambridge, 1985 to obtain results in non-compact settings. Existence theorems on non-compact generalized bi-complementarity problems for quasi-semi-monotone and bi-quasi-semi-monotone operators are also obtained. Moreover, as applications of some results of this paper on generalized bi-quasi-variational inequalities, we shall obtain existence of solutions for some kind of minimization problems with quasi- semi-monotone and bi-quasi-semi-monotone operators.

Manufacturing parabolic mirrors

CERN Multimedia

CERN PhotoLab

1975-01-01

The photo shows the construction of a vertical centrifuge mounted on an air cushion, with a precision of 1/10000 during rotation, used for the manufacture of very high=precision parabolic mirrors. (See Annual Report 1974.)

Inequalities and bounds for nucleon-nucleon scattering

International Nuclear Information System (INIS)

Ramandurai, K.S.

1979-08-01

The objective of this work is to derive model-independent inequalities and bounds for nucleon-nucleon elastic scattering amplitudes based on well-established theoretical principles and symmetries. Two classes of methods are used: algebraic and variational. In the algebraic part, the author derives inequalities and bounds for NN amplitudes and observables using their mutual relations and x symmetries. In the variational part, he employs Lagrange's method of undetermined multipliers to evaluate the bounds. He tests the predictions of a sample of proposed phase shifts at three different energies using the results obtained

Generalization of the Peierls-Bogolyubov inequality by means of a quantum-mechanical variational principle

International Nuclear Information System (INIS)

Soldatov, A.V.

2000-01-01

The Peierls-Bogolyubov inequality was generalized and a set of inequalities was derived instead, so that every subsequent inequality in this set approximates the quality in question with better precision than the preceding one. These inequalities lead to a sequence of improving upper bounds to the free energy of a quantum system if this system allows representation in terms of coherent states [ru

Photovoltaic applications of Compound Parabolic Concentrator (CPC)

Science.gov (United States)

Winston, R.

1975-01-01

The use of a compound parabolic concentrator as field collector, in conjunction with a primary focusing concentrator for photovoltaic applications is studied. The primary focusing concentrator can be a parabolic reflector, an array of Fresnel mirrors, a Fresnel lens or some other lens. Silicon solar cell grid structures are proposed that increase efficiency with concentration up to 10 suns. A ray tracing program has been developed to determine energy distribution at the exit of a compound parabolic concentrator. Projected total cost of a CPC/solar cell system will be between 4 and 5 times lower than for flat plate silicon cell arrays.

Income inequality and child maltreatment in the United States.

Science.gov (United States)

Eckenrode, John; Smith, Elliott G; McCarthy, Margaret E; Dineen, Michael

2014-03-01

To examine the relation between county-level income inequality and rates of child maltreatment. Data on substantiated reports of child abuse and neglect from 2005 to 2009 were obtained from the National Child Abuse and Neglect Data System. County-level data on income inequality and children in poverty were obtained from the American Community Survey. Data for additional control variables were obtained from the American Community Survey and the Health Resources and Services Administration Area Resource File. The Gini coefficient was used as the measure of income inequality. Generalized additive models were estimated to explore linear and nonlinear relations among income inequality, poverty, and child maltreatment. In all models, state was included as a fixed effect to control for state-level differences in victim rates. Considerable variation in income inequality and child maltreatment rates was found across the 3142 US counties. Income inequality, as well as child poverty rate, was positively and significantly correlated with child maltreatment rates at the county level. Controlling for child poverty, demographic and economic control variables, and state-level variation in maltreatment rates, there was a significant linear effect of inequality on child maltreatment rates (P income inequality across US counties was significantly associated with higher county-level rates of child maltreatment. The findings contribute to the growing literature linking greater income inequality to a range of poor health and well-being outcomes in infants and children.

Changes in income inequality and the health of immigrants.

Science.gov (United States)

Hamilton, Tod G; Kawachi, Ichiro

2013-03-01

Research suggests that income inequality is inversely associated with health. This association has been documented in studies that utilize variation in income inequality across countries or across time from a single country. The primary criticism of these approaches is their inability to account for potential confounders that are associated with income inequality. This paper uses variation in individual experiences of income inequality among immigrants within the United States (U.S.) to evaluate whether individuals who moved from countries with greater income inequality than the U.S. have better health than those who migrated from countries with less income in equality than the U.S. Utilizing individual-level (March Current Population Survey) and country-level data (the United Nations Human Development Reports), we show that among immigrants who have resided in the U.S. between 6 and 20 years, self-reported health is more favorable for the immigrants in the former category (i.e., greater income inequality) than those in the latter (i.e., lower income inequality). Results also show that self-reported health is better among immigrants from more developed countries and those who have more years of education, are male, and are married. Copyright © 2012. Published by Elsevier Ltd.

Occupational class inequalities in health across employment sectors: the contribution of working conditions.

Science.gov (United States)

Lahelma, Eero; Laaksonen, Mikko; Aittomäki, Akseli

2009-01-01

While health inequalities among employees are well documented, their variation and determinants among employee subpopulations are poorly understood. We examined variations in occupational class inequalities in health within four employment sectors and the contribution of working conditions to these inequalities. Cross-sectional data from the Helsinki Health Study in 2000-2002 were used. Each year, employees of the City of Helsinki, aged 40-60 years, received a mailed questionnaire (n = 8,960, 80% women, overall response rate for 3 years 67%). The outcome was physical health functioning measured by the overall physical component summary of SF-36. The socioeconomic indicator was occupational social class. Employment sectors studied were health care, education, social welfare and administration (n = 6,557). Physical and mental workload, and job demands and job control were explanatory factors. Inequality indices from logistic regression analysis were calculated. Occupational class inequalities in physical health functioning were slightly larger in education (1.47) than in the other sectors (1.43-1.40). Physical workload explained 95% of inequalities in social welfare and 32-36% in the other sectors. Job control also partly explained health inequalities. However, adjusting for mental workload and job demands resulted in larger health inequalities. Inequalities in physical health functioning were found within each employment sector, with minor variation in their magnitude. Physical workload was the main explanation for these inequalities, but its contribution varied between the sectors. In contrast, considering psychosocial working conditions led to wider inequalities. Improving physical working conditions among the lower occupational classes would help reduce health inequalities within different employment sectors.

Controllable parabolic lensed liquid-core optical fiber by using electrostatic force.

Science.gov (United States)

Tang, Chun Yin; Zhang, Xuming; Chai, Yang; Hui, Long; Tao, Lili; Tsang, Yuen H

2014-08-25

For typical optical fiber system, an external lens accessory set is required to adjust the optical path of output light, which however is limited by the fixed parameter of the lens accessory setup. Considering spherical aberration in the imaging process and its small focusable spot size, a complicated lens combination is required to compensate the aberration. This paper has demonstrated a unique method to fabricate liquid-core lensed fibers by filling water and NOA61 respectively into hollow Teflon AF fibers and silicate fiber, the radius of curvature of the liquid lens can be controlled by adjusting the applied voltage on the core liquid and even parabolic shape lens can be produced with enough applied voltage. The experiment has successfully demonstrated a variation of focal length from 0.628 mm to 0.111 mm responding to the change of applied voltage from 0V to 3.2KV (L = 2mm) for the Teflon AF fiber, as well as a variation of focal length from 0.274 mm to 0.08 mm responding to the change of applied voltage from 0V to 3KV (L = 2mm) for the silicate fiber. Further simulation shows that the focused spot size can be reduced to 2 µm by adjusting the refractive index and fiber geometry. Solid state parabolic lensed fiber can be produced after NOA61 is solidified by the UV curing.

A frictional contact problem with damage and adhesion for an electro elastic-viscoplastic body

Directory of Open Access Journals (Sweden)

Adel Aissaoui

2014-01-01

Full Text Available We consider a quasistatic frictional contact problem for an electro elastic-viscopalastic body with damage and adhestion. The contact is modelled with normal compliance. The adhesion of the contact surfaces is taken into account and modelled by a surface variable. We derive variational formulation for the model which is in the form of a system involving the displacement field, the electric potential field, the damage field and the adhesion field. We prove the existence of a unique weak solution to the problem. The proof is based on arguments of time-dependent variational inequalities, parabolic inequalities, differential equations and fixed point.

Federal technology alert. Parabolic-trough solar water heating

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-04-01

Parabolic-trough solar water heating is a well-proven renewable energy technology with considerable potential for application at Federal facilities. For the US, parabolic-trough water-heating systems are most cost effective in the Southwest where direct solar radiation is high. Jails, hospitals, barracks, and other facilities that consistently use large volumes of hot water are particularly good candidates, as are facilities with central plants for district heating. As with any renewable energy or energy efficiency technology requiring significant initial capital investment, the primary condition that will make a parabolic-trough system economically viable is if it is replacing expensive conventional water heating. In combination with absorption cooling systems, parabolic-trough collectors can also be used for air-conditioning. Industrial Solar Technology (IST) of Golden, Colorado, is the sole current manufacturer of parabolic-trough solar water heating systems. IST has an Indefinite Delivery/Indefinite Quantity (IDIQ) contract with the Federal Energy Management Program (FEMP) of the US Department of Energy (DOE) to finance and install parabolic-trough solar water heating on an Energy Savings Performance Contract (ESPC) basis for any Federal facility that requests it and for which it proves viable. For an ESPC project, the facility does not pay for design, capital equipment, or installation. Instead, it pays only for guaranteed energy savings. Preparing and implementing delivery or task orders against the IDIQ is much simpler than the standard procurement process. This Federal Technology Alert (FTA) of the New Technology Demonstration Program is one of a series of guides to renewable energy and new energy-efficient technologies.

Simulation of the parabolic trough solar energy generation system with Organic Rankine Cycle

International Nuclear Information System (INIS)

He, Ya-Ling; Mei, Dan-Hua; Tao, Wen-Quan; Yang, Wei-Wei; Liu, Huai-Liang

2012-01-01

Highlights: ► A parabolic trough solar power generation system with ORC is numerically simulated. ► The effects of key parameters on collector field and system performance are studied. ► Collector heat loss increases with small absorber and glass tube interlayer pressure. ► Heat collecting efficiency increases with initial increase of absorber HTO flow rate. ► Recommended thermal storage system volumes are different in year four typical days. -- Abstract: A model for a typical parabolic trough solar thermal power generation system with Organic Rankine Cycle (PT-SEGS–ORC) was built within the transient energy simulation package TRNSYS, which is formed by integrating several submodels for the trough collector system, the single-tank thermal storage system, the auxiliary power system and the heat-electricity conversion system. With this model, the effects of several key parameters, including the interlayer pressure between the absorber tube and the glass tube (p inter ), the flow rate of high temperature oil in the absorber tube (v), solar radiation intensity (I dn ) and incidence angle (θ), on the performance of the parabolic trough collector field based on the meteorological data of Xi’an city were examined. The study shows that the heat loss of the solar collector (q loss ) increases sharply with the increase in p inter at beginning and then reaches to an approximately constant value. The variation of heat collecting efficiency (η hc ) with v is quite similar to the variation of q loss with p inter . However, I dn and θ exhibit opposite effect on η hc . In addition, it is found that the optimal volume of the thermal storage system is sensitively dependent on the solar radiation intensity. The optimal volumes are 100, 150, 50, and 0 m 3 for spring equinox, summer solstice, autumnal equinox and winter solstice, respectively.

Carbon inequality at the sub-national scale: A case study of provincial-level inequality in CO2 emissions in China 1997-2007

International Nuclear Information System (INIS)

Clarke-Sather, Afton; Qu Jiansheng; Wang Qin; Zeng Jingjing; Li Yan

2011-01-01

This study asks whether sub-national inequalities in carbon dioxide (CO 2 ) emissions mirror international patterns in carbon inequality using the case study of China. Several studies have examined global-level carbon inequality; however, such approaches have not been used on a sub-national scale. This study examines inter-provincial inequality in CO 2 emissions within China using common measures of inequality (coefficient of variation, Gini Index, Theil Index) to analyze provincial-level data derived from the IPCC reference approach for the years 1997-2007. It decomposes CO 2 emissions inequality into its inter-regional and intra-regional components. Patterns of per capita CO 2 emissions inequality in China appear superficially similar to, though slightly lower than, per capita income inequality. However, decomposing these inequalities reveals different patterns. While inter-provincial income inequality is highly regional in character, inter-provincial CO 2 emissions inequality is primarily intra-regional. While apparently similar, global patterns in CO 2 emissions are not mirrored at the sub-national scale. - Highlights: → Carbon inequality is different in character within China than at global scale. → Interprovincial CO 2 emissions inequality in China is slightly lower than income inequality. → Interprovincial GDP inequality in China is regional in character. → Interprovincial CO 2 emissions inequality in China is not regional in character.

Partial differential equations of parabolic type

CERN Document Server

Friedman, Avner

2008-01-01

This accessible and self-contained treatment provides even readers previously unacquainted with parabolic and elliptic equations with sufficient background to understand research literature. Author Avner Friedman - Director of the Mathematical Biosciences Institute at The Ohio State University - offers a systematic and thorough approach that begins with the main facts of the general theory of second order linear parabolic equations. Subsequent chapters explore asymptotic behavior of solutions, semi-linear equations and free boundary problems, and the extension of results concerning fundamenta

Mixed hyperbolic-second-order-parabolic formulations of general relativity

International Nuclear Information System (INIS)

Paschalidis, Vasileios

2008-01-01

Two new formulations of general relativity are introduced. The first one is a parabolization of the Arnowitt-Deser-Misner formulation and is derived by the addition of combinations of the constraints and their derivatives to the right-hand side of the Arnowitt-Deser-Misner evolution equations. The desirable property of this modification is that it turns the surface of constraints into a local attractor because the constraint propagation equations become second-order parabolic independently of the gauge conditions employed. This system may be classified as mixed hyperbolic--second-order parabolic. The second formulation is a parabolization of the Kidder-Scheel-Teukolsky formulation and is a manifestly mixed strongly hyperbolic--second-order-parabolic set of equations, bearing thus resemblance to the compressible Navier-Stokes equations. As a first test, a stability analysis of flat space is carried out and it is shown that the first modification exponentially damps and smoothes all constraint-violating modes. These systems provide a new basis for constructing schemes for long-term and stable numerical integration of the Einstein field equations.

Carbon inequality at the sub-national scale: A case study of provincial-level inequality in CO{sub 2} emissions in China 1997-2007

Energy Technology Data Exchange (ETDEWEB)

Clarke-Sather, Afton, E-mail: Afton.Clarke-Sather@colorado.edu [Scientific Information Center for Resources and Environment, Lanzhou Branch of the National Science Library, Chinese Academy of Sciences, 8 Middle Tianshui Road, Lanzhou 730000 (China); Department of Geography, University of Colorado, Boulder, 260 UCB, Boulder, CO 80309 (United States); Qu Jiansheng [Scientific Information Center for Resources and Environment, Lanzhou Branch of the National Science Library, Chinese Academy of Sciences, 8 Middle Tianshui Road, Lanzhou 730000 (China); MOE Key Laboratory of Western China' s Environmental Systems, Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou (China); Wang Qin [MOE Key Laboratory of Western China' s Environmental Systems, Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou (China); Zeng Jingjing [Scientific Information Center for Resources and Environment, Lanzhou Branch of the National Science Library, Chinese Academy of Sciences, 8 Middle Tianshui Road, Lanzhou 730000 (China); Li Yan [MOE Key Laboratory of Western China' s Environmental Systems, Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou (China)

2011-09-15

This study asks whether sub-national inequalities in carbon dioxide (CO{sub 2}) emissions mirror international patterns in carbon inequality using the case study of China. Several studies have examined global-level carbon inequality; however, such approaches have not been used on a sub-national scale. This study examines inter-provincial inequality in CO{sub 2} emissions within China using common measures of inequality (coefficient of variation, Gini Index, Theil Index) to analyze provincial-level data derived from the IPCC reference approach for the years 1997-2007. It decomposes CO{sub 2} emissions inequality into its inter-regional and intra-regional components. Patterns of per capita CO{sub 2} emissions inequality in China appear superficially similar to, though slightly lower than, per capita income inequality. However, decomposing these inequalities reveals different patterns. While inter-provincial income inequality is highly regional in character, inter-provincial CO{sub 2} emissions inequality is primarily intra-regional. While apparently similar, global patterns in CO{sub 2} emissions are not mirrored at the sub-national scale. - Highlights: > Carbon inequality is different in character within China than at global scale. > Interprovincial CO{sub 2} emissions inequality in China is slightly lower than income inequality. > Interprovincial GDP inequality in China is regional in character. > Interprovincial CO{sub 2} emissions inequality in China is not regional in character.

Moduli of Parabolic Higgs Bundles and Atiyah Algebroids

DEFF Research Database (Denmark)

Logares, Marina; Martens, Johan

2010-01-01

In this paper we study the geometry of the moduli space of (non-strongly) parabolic Higgs bundles over a Riemann surface with marked points. We show that this space possesses a Poisson structure, extending the one on the dual of an Atiyah algebroid over the moduli space of parabolic vector bundle...

Performance and Simulation of a Stand-alone Parabolic Trough Solar Thermal Power Plant

Science.gov (United States)

Mohammad, S. T.; Al-Kayiem, H. H.; Assadi, M. K.; Gilani, S. I. U. H.; Khlief, A. K.

2018-05-01

In this paper, a Simulink® Thermolib Model has been established for simulation performance evaluation of Stand-alone Parabolic Trough Solar Thermal Power Plant in Universiti Teknologi PETRONAS, Malaysia. This paper proposes a design of 1.2 kW parabolic trough power plant. The model is capable to predict temperatures at any system outlet in the plant, as well as the power output produced. The conditions that are taken into account as input to the model are: local solar radiation and ambient temperatures, which have been measured during the year. Other parameters that have been input to the model are the collector’s sizes, location in terms of latitude and altitude. Lastly, the results are presented in graphical manner to describe the analysed variations of various outputs of the solar fields obtained, and help to predict the performance of the plant. The developed model allows an initial evaluation of the viability and technical feasibility of any similar solar thermal power plant.

Reduction of intensity variations on a photovoltaic array with compound parabolic concentrators

Science.gov (United States)

Greenman, P.; Ogallagher, J.; Winston, R.; Costogue, E.

1979-01-01

The reduction of nonuniformities in the intensity distribution of light focused on a photovoltaic array by a compound parabolic concentrator is investigated. The introduction of small distortions into the surfaces of the reflector in order to diffuse the incident collimated light to fill the angular acceptance of the concentrator is calculated by means of ray tracing to decrease the irradiance nonuniformity at the cost of a lowered effective concentration of the concentrator. Measurements of the intensity distribution on a scale test model in terrestrial sunlight with corrugated aluminized mylar reflectors are shown to be in good agreement with the ray tracing results. A two-stage concentrator consisting of a focusing primary and a nonimaging secondary is also shown to result in a fairly uniform intensity distribution except in the case of a 4-deg incidence angle, which may be corrected by the introduction of distortions into one or both concentration stages.

High-Power, High-Intensity Laser Propagation and Interactions

Science.gov (United States)

2014-03-10

intensity as the weighting function. The full refractive index associated with the laser plasma interaction having a parabolic density variation ...radiation in turn enhances the electron density wave further amplifying the radiation. Considering spatial variations in the z direction only the FEL...effL/ at the entrance to the wiggler where effL is the effective interaction length. This requirement can be expressed by the following inequality

Educational inequalities in self-rated health across US states and European countries.

Science.gov (United States)

Präg, Patrick; Subramanian, S V

2017-07-01

The US shows a distinct health disadvantage when compared to other high-income nations. A potential lever to reduce this disadvantage is to improve the health situation of lower socioeconomic groups. Our objective is to explore how the considerable within-US variation in health inequalities compares to the health inequalities across other Western countries. Representative survey data from 44 European countries and the US federal states were obtained from the fourth wave of the European Values Study (EVS) and the 2008 wave of the Behavioral Risk Factor Surveillance System. Using binary logistic regression, we analyze different forms of educational inequalities in self-rated health (SRH), adjusted for age and sex. The extent of educational inequalities in SRH varies considerably over European countries and US states; with US states in general showing greater inequality, however, differences between US states and European countries are less clear than commonly assumed. The US has considerable differences in educational inequalities in SRH across geographic locations. To understand the reasons for the US health disadvantage, comparative research has to take into account the vast variation in health inequalities within the US.

Moduli space of Parabolic vector bundles over hyperelliptic curves

Indian Academy of Sciences (India)

27

This has been generalized for higher dimensional varieties by Maruyama ... Key words and phrases. Parabolic structure .... Let E be a vector bundle of rank r on X. Recall that a parabolic ..... Let us understand this picture geometrically. Let ω1 ...

A compact representation of drawing movements with sequences of parabolic primitives.

Directory of Open Access Journals (Sweden)

Felix Polyakov

2009-07-01

Full Text Available Some studies suggest that complex arm movements in humans and monkeys may optimize several objective functions, while others claim that arm movements satisfy geometric constraints and are composed of elementary components. However, the ability to unify different constraints has remained an open question. The criterion for a maximally smooth (minimizing jerk motion is satisfied for parabolic trajectories having constant equi-affine speed, which thus comply with the geometric constraint known as the two-thirds power law. Here we empirically test the hypothesis that parabolic segments provide a compact representation of spontaneous drawing movements. Monkey scribblings performed during a period of practice were recorded. Practiced hand paths could be approximated well by relatively long parabolic segments. Following practice, the orientations and spatial locations of the fitted parabolic segments could be drawn from only 2-4 clusters, and there was less discrepancy between the fitted parabolic segments and the executed paths. This enabled us to show that well-practiced spontaneous scribbling movements can be represented as sequences ("words" of a small number of elementary parabolic primitives ("letters". A movement primitive can be defined as a movement entity that cannot be intentionally stopped before its completion. We found that in a well-trained monkey a movement was usually decelerated after receiving a reward, but it stopped only after the completion of a sequence composed of several parabolic segments. Piece-wise parabolic segments can be generated by applying affine geometric transformations to a single parabolic template. Thus, complex movements might be constructed by applying sequences of suitable geometric transformations to a few templates. Our findings therefore suggest that the motor system aims at achieving more parsimonious internal representations through practice, that parabolas serve as geometric primitives and that non

Recovering the source and initial value simultaneously in a parabolic equation

International Nuclear Information System (INIS)

Zheng, Guang-Hui; Wei, Ting

2014-01-01

In this paper, we consider an inverse problem to simultaneously reconstruct the source term and initial data associated with a parabolic equation based on the additional temperature data at a terminal time t = T and the temperature data on an accessible part of a boundary. The conditional stability and uniqueness of the inverse problem are established. We apply a variational regularization method to recover the source and initial value. The existence, uniqueness and stability of the minimizer of the corresponding variational problem are obtained. Taking the minimizer as a regularized solution for the inverse problem, under an a priori and an a posteriori parameter choice rule, the convergence rates of the regularized solution under a source condition are also given. Furthermore, the source condition is characterized by an optimal control approach. Finally, we use a conjugate gradient method and a stopping criterion given by Morozov's discrepancy principle to solve the variational problem. Numerical experiments are provided to demonstrate the feasibility of the method. (papers)

A comparative Thermal Analysis of conventional parabolic receiver tube and Cavity model tube in a Solar Parabolic Concentrator

Science.gov (United States)

Arumugam, S.; Ramakrishna, P.; Sangavi, S.

2018-02-01

Improvements in heating technology with solar energy is gaining focus, especially solar parabolic collectors. Solar heating in conventional parabolic collectors is done with the help of radiation concentration on receiver tubes. Conventional receiver tubes are open to atmosphere and loose heat by ambient air currents. In order to reduce the convection losses and also to improve the aperture area, we designed a tube with cavity. This study is a comparative performance behaviour of conventional tube and cavity model tube. The performance formulae were derived for the cavity model based on conventional model. Reduction in overall heat loss coefficient was observed for cavity model, though collector heat removal factor and collector efficiency were nearly same for both models. Improvement in efficiency was also observed in the cavity model’s performance. The approach towards the design of a cavity model tube as the receiver tube in solar parabolic collectors gave improved results and proved as a good consideration.

The relative contribution of income inequality and imprisonment to the variation in homicide rates among Developed (OECD), South and Central American countries.

Science.gov (United States)

Nadanovsky, Paulo; Cunha-Cruz, Joana

2009-11-01

Homicide rates vary widely across and within different continents. In order to address the problem of violence in the world, it seems important to clarify the sources of this variability. Despite the fact that income inequality and imprisonment seem to be two of the most important determinants of the variation in homicide rates over space and time, the concomitant effect of income inequality and imprisonment on homicide has not been examined. The objective of this cross-sectional ecological study was to investigate the association of income inequality and imprisonment with homicide rates among Developed (OECD), South and Central American countries. A novel index was developed to indicate imprisonment: the Impunity Index (the total number of homicides in the preceding decade divided by the number of persons in prison at a single slice in time). Negative binomial models were used to estimate rate ratios of homicides for young males and for the total population in relation to Gini Index and Impunity Index, controlling for infant mortality (as a proxy for poverty levels), Gross Domestic Product per-capita, education, percentage of young males in the population and urbanization. Both low income inequality and low impunity (high imprisonment of criminals) were related to low homicide rates. In addition, we found that countries with lower income inequality, lower infant mortality (less poverty), higher average income (GDP per-capita) and higher levels of education had low impunity. Our results are compatible with the hypothesis that both low income inequality and imprisonment of criminals, independent of each other and of other social-structural circumstances, may greatly contribute to the reduction in homicide rates in South and Central American countries, and to the maintenance of low levels of homicides in OECD countries. The Impunity Index reveals that countries that show greater commitment to education and to distribution of income also show greater commitment to

Environmental Controls and Eco-geomorphic Interactions of the Barchan-to-parabolic Dune Stabilisation and the Parabolic-to-barchan Dune Reactivation

Science.gov (United States)

Yan, Na; Baas, Andreas

2015-04-01

Parabolic dunes are one of a few common aeolian landforms which are highly controlled by eco-geomorphic interactions. Parabolic dunes, on the one hand, can be developed from highly mobile dune landforms, barchans for instance, in an ameliorated vegetation condition; or on the other hand, they can be reactivated and transformed back into mobile dunes due to vegetation deterioration. The fundamental mechanisms and eco-geomorphic interactions controlling both dune transformations remain poorly understood. To bridge the gap between complex processes involved in dune transformations on a relatively long temporal scale and real world monitoring records on a very limited temporal scale, this research has extended the DECAL model to incorporate 'dynamic' growth functions and the different 'growth' of perennial shrubs between growing and non-growing seasons, informed by field measurements and remote sensing analysis, to explore environmental controls and eco-geomorphic interactions of both types of dune transformation. A non-dimensional 'dune stabilising index' is proposed to capture the interactions between environmental controls (i.e. the capabilities of vegetation to withstand wind erosion and sand burial, the sandy substratum thickness, the height of the initial dune, and the sand transport potential), and establish the linkage between these controls and the geometry of a stabilising dune. An example demonstrates how to use the power-law relationship between the dune stabilising index and the normalised migration distance to assist in extrapolating the historical trajectories of transforming dunes. The modelling results also show that a slight increase in vegetation cover of an initial parabolic dune can significantly increase the reactivation threshold of climatic impact (both drought stress and wind strength) required to reactivate a stabilising parabolic dune into a barchan. Four eco-geomorphic interaction zones that govern a barchan-to-parabolic dune transformation

Finite-time blow-up for quasilinear degenerate Keller-Segel systems of parabolic-parabolic type

Science.gov (United States)

Hashira, Takahiro; Ishida, Sachiko; Yokota, Tomomi

2018-05-01

This paper deals with the quasilinear degenerate Keller-Segel systems of parabolic-parabolic type in a ball of RN (N ≥ 2). In the case of non-degenerate diffusion, Cieślak-Stinner [3,4] proved that if q > m + 2/N, where m denotes the intensity of diffusion and q denotes the nonlinearity, then there exist initial data such that the corresponding solution blows up in finite time. As to the case of degenerate diffusion, it is known that a solution blows up if q > m + 2/N (see Ishida-Yokota [13]); however, whether the blow-up time is finite or infinite has been unknown. This paper gives an answer to the unsolved problem. Indeed, the finite-time blow-up of energy solutions is established when q > m + 2/N.

Flux form Semi-Lagrangian methods for parabolic problems

Directory of Open Access Journals (Sweden)

Bonaventura Luca

2016-09-01

Full Text Available A semi-Lagrangian method for parabolic problems is proposed, that extends previous work by the authors to achieve a fully conservative, flux-form discretization of linear and nonlinear diffusion equations. A basic consistency and stability analysis is proposed. Numerical examples validate the proposed method and display its potential for consistent semi-Lagrangian discretization of advection diffusion and nonlinear parabolic problems.

Estimates of the stabilization rate as t→∞ of solutions of the first mixed problem for a quasilinear system of second-order parabolic equations

International Nuclear Information System (INIS)

Kozhevnikova, L M; Mukminov, F Kh

2000-01-01

A quasilinear system of parabolic equations with energy inequality is considered in a cylindrical domain {t>0}xΩ. In a broad class of unbounded domains Ω two geometric characteristics of a domain are identified which determine the rate of convergence to zero as t→∞ of the L 2 -norm of a solution. Under additional assumptions on the coefficients of the quasilinear system estimates of the derivatives and uniform estimates of the solution are obtained; they are proved to be best possible in the order of convergence to zero in the case of one semilinear equation

Do Socioeconomic Inequalities in Neonatal Mortality Reflect Inequalities in Coverage of Maternal Health Services? Evidence from 48 Low- and Middle-Income Countries.

Science.gov (United States)

McKinnon, Britt; Harper, Sam; Kaufman, Jay S

2016-02-01

To examine socioeconomic and health system determinants of wealth-related inequalities in neonatal mortality rates (NMR) across 48 low- and middle-income countries. We used data from Demographic and Health Surveys conducted between 2006 and 2012. Absolute and relative inequalities for NMR and coverage of antenatal care, facility-based delivery, and Caesarean delivery were measured using the Slope Index of Inequality and Relative Index of Inequality, respectively. Meta-regression was used to assess whether variation in the magnitude of NMR inequalities was associated with inequalities in coverage of maternal health services, and whether country-level economic and health system factors were associated with mean NMR and socioeconomic inequality in NMR. Of the three maternal health service indicators examined, the magnitude of socioeconomic inequality in NMR was most strongly related to inequalities in antenatal care. NMR inequality was greatest in countries with higher out-of-pocket health expenditures, more doctors per capita, and a higher adolescent fertility rate. Determinants of lower mean NMR (e.g., higher government health expenditures and a greater number of nurses/midwives per capita) differed from factors associated with lower NMR inequality. Reducing the financial burden of maternal health services and achieving universal coverage of antenatal care may contribute to a reduction in socioeconomic differences in NMR. Further investigation of the mechanisms contributing to these cross-national associations seems warranted.

Applications of Sharp Interface Method for Flow Dynamics, Scattering and Control Problems

Science.gov (United States)

2012-07-30

Reynolds number, Advances in Applied Mathematics and Mechanics, to appear. 17. K. Ito and K. Kunisch, Optimal Control of Parabolic Variational ...provides more precise and detailed sensitivity of the solution and describes the dynamical change due to the variation in the Reynolds number. The immersed... Inequalities , Journal de Math. Pures et Appl, 93 (2010), no. 4, 329-360. 18. K. Ito and K. Kunisch, Semi-smooth Newton Methods for Time-Optimal Control for a

Structural interaction between gender and race inequality in Brazil

Directory of Open Access Journals (Sweden)

José Alcides Figueiredo Santos

2010-01-01

Full Text Available This paper is guided by the theoretical notion that social divisions generate effects derived from its structural interaction. Having in mind this theoretical motivation, it estimates the gender earnings gap among white e non white (black and mixed color groups in Brazil. All the eight Generalized Linear Models estimated, whose variables are successively included, show that the gender gap is big across both racial groups but it is bigger among whites. The investigation explores the role of the underlying context of class inequality, as well as others factors, on understanding the racial variation of the gender inequality. The study considers that the characteristics of the racial inequality in Brazil, as well as the intersection between class and race, explain the bigger gender advantage for the white man. The racial hierarchy establishes limits of variation on the gender hierarchy for the non white.

Parabolic-trough technology roadmap: A pathway for sustained commercial development and deployment of parabolic-trough technology

International Nuclear Information System (INIS)

David Kearney; Hank Price

1999-01-01

Technology roadmapping is a needs-driven technology planning process to help identify, select, and develop technology alternatives to satisfy a set of market needs. The DOE's Office of Power Technologies' Concentrating Solar Power (CSP) Program recently sponsored a technology roadmapping workshop for parabolic trough technology. The workshop was attended by an impressive cross section of industry and research experts. The goals of the workshop were to evaluate the market potential for trough power projects, develop a better understanding of the current state of the technology, and to develop a conceptual plan for advancing the state of parabolic trough technology. This report documents and extends the roadmap that was conceptually developed during the workshop

Inequality, income, and poverty: comparative global evidence.

Science.gov (United States)

Fosu, Augustin Kwasi

2010-01-01

Objectives. The study seeks to provide comparative global evidence on the role of income inequality, relative to income growth, in poverty reduction.Methods. An analysis-of-covariance model is estimated using a large global sample of 1980–2004 unbalanced panel data, with the headcount measure of poverty as the dependent variable, and the Gini coefficient and PPP-adjusted mean income as explanatory variables. Both random-effects and fixed-effects methods are employed in the estimation.Results. The responsiveness of poverty to income is a decreasing function of inequality, and the inequality elasticity of poverty is actually larger than the income elasticity of poverty. Furthermore, there is a large variation across regions (and countries) in the relative effects of inequality on poverty.Conclusion. Income distribution plays a more important role than might be traditionally acknowledged in poverty reduction, though this importance varies widely across regions and countries.

Hermitian-Einstein metrics on parabolic stable bundles

International Nuclear Information System (INIS)

Li Jiayu; Narasimhan, M.S.

1995-12-01

Let M-bar be a compact complex manifold of complex dimension two with a smooth Kaehler metric and D a smooth divisor on M-bar. If E is a rank 2 holomorphic vector bundle on M-bar with a stable parabolic structure along D, we prove the existence of a metric on E' = E module MbarD (compatible with the parabolic structure) which is Hermitian-Einstein with respect to the restriction of Kaehler metric of M-barD. A converse is also proved. (author). 24 refs

Area-level income inequality and oral health among Australian adults-A population-based multilevel study.

Directory of Open Access Journals (Sweden)

Ankur Singh

Full Text Available A lack of evidence exists on the association between area-level income inequality and oral health within Australia. This study examined associations between area-level income inequality and oral health outcomes (inadequate dentition (<21 teeth and poor self-rated oral health among Australian adults. Variations in the association between area-level income inequality and oral health outcomes according to area-level mean income were also assessed. Finally, household-income gradients in oral health outcomes according to area-level income inequality were compared.For the analyses, data on Australian dentate adults (n = 5,165 nested in 435 Local Government Areas (LGAs was obtained from the National Dental Telephone Interview Survey-2013. Multilevel multivariable logistic regression models with random intercept and fixed slopes were fitted to test associations between area-level income inequality and oral health outcomes, examine variations in associations according to area-level mean income, and examine variations in household-income gradients in outcomes according to area-level income inequality. Covariates included age, sex, LGA-level mean weekly household income, geographic remoteness and household income.LGA-level income inequality was not associated with poor self-rated oral health and inversely associated with inadequate dentition (OR: 0.64; 95% CI: 0.48, 0.87 after adjusting for covariates. Inverse association between income inequality and inadequate dentition at the individual level was limited to LGAs within the highest tertile of mean weekly household income. Household income gradients in both outcomes showed poorer oral health at lower levels of household income. The household income gradients for inadequate dentition varied according to the LGA-level income inequality.Findings suggest that income inequality at the LGA-level in Australia is not positively associated with poorer oral health outcomes. Inverse association between income

Optical nonlinearities associated to applied electric fields in parabolic two-dimensional quantum rings

International Nuclear Information System (INIS)

Duque, C.M.; Morales, A.L.; Mora-Ramos, M.E.; Duque, C.A.

2013-01-01

The linear and nonlinear optical absorption as well as the linear and nonlinear corrections to the refractive index are calculated in a disc shaped quantum dot under the effect of an external magnetic field and parabolic and inverse square confining potentials. The exact solutions for the two-dimensional motion of the conduction band electrons are used as the basis for a perturbation-theory treatment of the effect of a static applied electric field. In general terms, the variation of one of the different potential energy parameters – for a fixed configuration of the remaining ones – leads to either blueshifts or redshifts of the resonant peaks as well as to distinct rates of change for their amplitudes. -- Highlights: • Optical absorption and corrections to the refractive in quantum dots. • Electric and magnetic field and parabolic and inverse square potentials. • Perturbation-theory treatment of the effect of the electric field. • Induced blueshifts or redshifts of the resonant peaks are studied. • Evolution of rates of change for amplitudes of resonant peaks

Optical nonlinearities associated to applied electric fields in parabolic two-dimensional quantum rings

Energy Technology Data Exchange (ETDEWEB)

Duque, C.M., E-mail: cduque@fisica.udea.edu.co [Instituto de Física, Universidad de Antioquia, AA 1226, Medellín (Colombia); Morales, A.L. [Instituto de Física, Universidad de Antioquia, AA 1226, Medellín (Colombia); Mora-Ramos, M.E. [Instituto de Física, Universidad de Antioquia, AA 1226, Medellín (Colombia); Facultad de Ciencias, Universidad Autónoma del Estado de Morelos, Ave. Universidad 1001, CP 62209, Cuernavaca, Morelos (Mexico); Duque, C.A. [Instituto de Física, Universidad de Antioquia, AA 1226, Medellín (Colombia)

2013-11-15

The linear and nonlinear optical absorption as well as the linear and nonlinear corrections to the refractive index are calculated in a disc shaped quantum dot under the effect of an external magnetic field and parabolic and inverse square confining potentials. The exact solutions for the two-dimensional motion of the conduction band electrons are used as the basis for a perturbation-theory treatment of the effect of a static applied electric field. In general terms, the variation of one of the different potential energy parameters – for a fixed configuration of the remaining ones – leads to either blueshifts or redshifts of the resonant peaks as well as to distinct rates of change for their amplitudes. -- Highlights: • Optical absorption and corrections to the refractive in quantum dots. • Electric and magnetic field and parabolic and inverse square potentials. • Perturbation-theory treatment of the effect of the electric field. • Induced blueshifts or redshifts of the resonant peaks are studied. • Evolution of rates of change for amplitudes of resonant peaks.

Linear and quasi-linear equations of parabolic type

CERN Document Server

Ladyženskaja, O A; Ural′ceva, N N; Uralceva, N N

1968-01-01

Equations of parabolic type are encountered in many areas of mathematics and mathematical physics, and those encountered most frequently are linear and quasi-linear parabolic equations of the second order. In this volume, boundary value problems for such equations are studied from two points of view: solvability, unique or otherwise, and the effect of smoothness properties of the functions entering the initial and boundary conditions on the smoothness of the solutions.

Explaining inequalities in women's mortality between U.S. States

Directory of Open Access Journals (Sweden)

Jennifer Karas Montez

2016-12-01

Full Text Available Inequalities in women's mortality between U.S. states are large and growing. It is unknown whether they reflect differences between states in their population characteristics, contextual characteristics, or both. This study systematically examines the large inequalities in women's mortality between U.S. states using a multilevel approach. It focuses on “fundamental” social determinants of mortality at the individual and state levels as potential explanations. We analyze data from the 2013 public-use National Longitudinal Mortality Study on women aged 45–89 years and estimate multilevel logistic regression models. The models include women's personal characteristics (age, race/ethnicity, education, employment, income, and marriage and states’ contextual characteristics (economic environment, social cohesion, sociopolitical orientation, physical infrastructure, and tobacco environment. We found that variation in women's mortality across states was significant (p<0.001. Adjusting for women's personal characteristics explained 30% of the variation. Additionally adjusting for states’ contextual characteristics explained 62% of the variation; the most important characteristics were social cohesion and economic conditions. No significant mortality differences between any two states remained after accounting for individual and contextual characteristics. Supplementary analyses of men indicate that state contexts have stronger and more pernicious consequences for women than men. Taken together, the findings underscore the importance of ‘bringing context back in’ and taking a multilevel approach when investigating geographic inequalities in U.S. mortality. Keywords: Mortality, Gender, Inequality, Social determinants, U.S. states, Multilevel

Describing Quadratic Cremer Point Polynomials by Parabolic Perturbations

DEFF Research Database (Denmark)

Sørensen, Dan Erik Krarup

1996-01-01

We describe two infinite order parabolic perturbation proceduresyielding quadratic polynomials having a Cremer fixed point. The main ideais to obtain the polynomial as the limit of repeated parabolic perturbations.The basic tool at each step is to control the behaviour of certain externalrays.......Polynomials of the Cremer type correspond to parameters at the boundary of ahyperbolic component of the Mandelbrot set. In this paper we concentrate onthe main cardioid component. We investigate the differences between two-sided(i.e. alternating) and one-sided parabolic perturbations.In the two-sided case, we prove...... the existence of polynomials having an explicitlygiven external ray accumulating both at the Cremer point and at its non-periodicpreimage. We think of the Julia set as containing a "topologists double comb".In the one-sided case we prove a weaker result: the existence of polynomials havingan explicitly given...

Mechatronic Prototype of Parabolic Solar Tracker.

Science.gov (United States)

Morón, Carlos; Díaz, Jorge Pablo; Ferrández, Daniel; Ramos, Mari Paz

2016-06-15

In the last 30 years numerous attempts have been made to improve the efficiency of the parabolic collectors in the electric power production, although most of the studies have focused on the industrial production of thermoelectric power. This research focuses on the application of this concentrating solar thermal power in the unexplored field of building construction. To that end, a mechatronic prototype of a hybrid paraboloidal and cylindrical-parabolic tracker based on the Arduido technology has been designed. The prototype is able to measure meteorological data autonomously in order to quantify the energy potential of any location. In this way, it is possible to reliably model real commercial equipment behavior before its deployment in buildings and single family houses.

Numerical performance of the parabolized ADM (PADM) formulation of General Relativity

OpenAIRE

Paschalidis, Vasileios; Hansen, Jakob; Khokhlov, Alexei

2007-01-01

In a recent paper the first coauthor presented a new parabolic extension (PADM) of the standard 3+1 Arnowitt, Deser, Misner formulation of the equations of general relativity. By parabolizing first-order ADM in a certain way, the PADM formulation turns it into a mixed hyperbolic - second-order parabolic, well-posed system. The surface of constraints of PADM becomes a local attractor for all solutions and all possible well-posed gauge conditions. This paper describes a numerical implementation...

L∞-error estimate for a system of elliptic quasivariational inequalities

Directory of Open Access Journals (Sweden)

M. Boulbrachene

2003-01-01

Full Text Available We deal with the numerical analysis of a system of elliptic quasivariational inequalities (QVIs. Under W2,p(Ω-regularity of the continuous solution, a quasi-optimal L∞-convergence of a piecewise linear finite element method is established, involving a monotone algorithm of Bensoussan-Lions type and standard uniform error estimates known for elliptic variational inequalities (VIs.

Determination of source terms in a degenerate parabolic equation

International Nuclear Information System (INIS)

Cannarsa, P; Tort, J; Yamamoto, M

2010-01-01

In this paper, we prove Lipschitz stability results for inverse source problems relative to parabolic equations. We use the method introduced by Imanuvilov and Yamamoto in 1998 based on Carleman estimates. What is new here is that we study a class of one-dimensional degenerate parabolic equations. In our model, the diffusion coefficient vanishes at one extreme point of the domain. Instead of the classical Carleman estimates obtained by Fursikov and Imanuvilov for non degenerate equations, we use and extend some recent Carleman estimates for degenerate equations obtained by Cannarsa, Martinez and Vancostenoble. Finally, we obtain Lipschitz stability results in inverse source problems for our class of degenerate parabolic equations both in the case of a boundary observation and in the case of a locally distributed observation

Interaction Potential between Parabolic Rotator and an Outside Particle

Directory of Open Access Journals (Sweden)

Dan Wang

2014-01-01

Full Text Available At micro/nanoscale, the interaction potential between parabolic rotator and a particle located outside the rotator is studied on the basis of the negative exponential pair potential 1/Rn between particles. Similar to two-dimensional curved surfaces, we confirm that the potential of the three-dimensional parabolic rotator and outside particle can also be expressed as a unified form of curvatures; that is, it can be written as the function of curvatures. Furthermore, we verify that the driving forces acting on the particle may be induced by the highly curved micro/nano-parabolic rotator. Curvatures and the gradient of curvatures are the essential elements forming the driving forces. Through the idealized numerical experiments, the accuracy of the curvature-based potential is preliminarily proved.

The sensitivity of the electron transport within bulk zinc-blende gallium nitride to variations in the crystal temperature, the doping concentration, and the non-parabolicity coefficient associated with the lowest energy conduction band valley

Energy Technology Data Exchange (ETDEWEB)

Siddiqua, Poppy; O' Leary, Stephen K., E-mail: stephen.oleary@ubc.ca [School of Engineering, The University of British Columbia, 3333 University Way, Kelowna, British Columbia V1V 1V7 (Canada)

2016-09-07

Within the framework of a semi-classical three-valley Monte Carlo simulation approach, we analyze the steady-state and transient electron transport that occurs within bulk zinc-blende gallium nitride. In particular, we examine how the steady-state and transient electron transport that occurs within this material changes in response to variations in the crystal temperature, the doping concentration, and the non-parabolicity coefficient associated with the lowest energy conduction band valley. These results are then contrasted with those corresponding to a number of other compound semiconductors of interest.

Off-Road Soft Soil Tire Model Development and Experimental Testing

Science.gov (United States)

2011-06-29

the traction of the vehi- cle. Most models that originated from the Wismur-Luth model used variations of the Wismur-Luth equations to account for...implementing the Mohr-Coulomb failure criteria, where the inequality in Eq. (9) bounds the shear stress. ( ) ( ) (9...17) For straight line driving at zero camber, a parabolic distribution of the pressure in the contact patch in the

Inequalities in health: approaches by health authorities in an English health region.

Science.gov (United States)

McCarron, P; Yates, B

2000-06-01

In 1995 the Department of Health published Variations in health: what can the Department of Health do? This recommended that health authorities should have a comprehensive plan for identifying and tackling variations in health. We investigated how health authorities in the South and West Region were taking forward this work. Semi-structured interviews and reviews of documentation were conducted in all health authorities in the South and West Region of England. All health authorities viewed tackling inequalities in health as important; however, explicit strategies did not exist and Health of the Nation targets were a vehicle for determining priorities of inequalities. Explicit corporate commitment was often weak. Analyses were being conducted to determine the magnitude of local health inequalities and to assist in designing appropriate interventions. The importance of alliance working was highlighted; much work was being done although success was variable. Efforts are being made throughout the South and West region to tackle inequalities in health. Although strategic vision at the corporate level was often lacking, there was evidence of commitment to taking the inequalities agenda forward within public health directorates. Strengthening of primary care and alliance working roles is essential. Recent national strategy documents, forthcoming legislation, and a review of health inequalities recognize the health effects of inequalities and require health authorities to collaborate with local partners to tackle these, and will offer opportunities to improve corporate commitment and alliance working. Uptake and success of these opportunities will have a major influence on progress in tackling health inequalities.

Mechatronic Prototype of Parabolic Solar Tracker

Directory of Open Access Journals (Sweden)

Carlos Morón

2016-06-01

Full Text Available In the last 30 years numerous attempts have been made to improve the efficiency of the parabolic collectors in the electric power production, although most of the studies have focused on the industrial production of thermoelectric power. This research focuses on the application of this concentrating solar thermal power in the unexplored field of building construction. To that end, a mechatronic prototype of a hybrid paraboloidal and cylindrical-parabolic tracker based on the Arduido technology has been designed. The prototype is able to measure meteorological data autonomously in order to quantify the energy potential of any location. In this way, it is possible to reliably model real commercial equipment behavior before its deployment in buildings and single family houses.

Nanofocusing parabolic refractive x-ray lenses

International Nuclear Information System (INIS)

Schroer, C.G.; Kuhlmann, M.; Hunger, U.T.; Guenzler, T.F.; Kurapova, O.; Feste, S.; Frehse, F.; Lengeler, B.; Drakopoulos, M.; Somogyi, A.; Simionovici, A.S.; Snigirev, A.; Snigireva, I.; Schug, C.; Schroeder, W.H.

2003-01-01

Parabolic refractive x-ray lenses with short focal distance can generate intensive hard x-ray microbeams with lateral extensions in the 100 nm range even at a short distance from a synchrotron radiation source. We have fabricated planar parabolic lenses made of silicon that have a focal distance in the range of a few millimeters at hard x-ray energies. In a crossed geometry, two lenses were used to generate a microbeam with a lateral size of 380 nm by 210 nm at 25 keV in a distance of 42 m from the synchrotron radiation source. Using diamond as the lens material, microbeams with a lateral size down to 20 nm and below are conceivable in the energy range from 10 to 100 keV

Computer aided FEA simulation of EN45A parabolic leaf spring

Directory of Open Access Journals (Sweden)

Krishan Kumar

2013-04-01

Full Text Available This paper describes computer aided finite element analysis of parabolic leaf spring. The present work is an improvement in design of EN45A parabolic leaf spring used by a light commercial automotive vehicle. Development of a leaf spring is a long process which requires lots of test to validate the design and manufacturing variables. A three-layer parabolic leaf spring of EN45A has been taken for this work. The thickness of leaves varies from center to the outer side following a parabolic pattern. These leaf springs are designed to become lighter, but also provide a much improved ride to the vehicle through a reduction on interleaf friction. The CAD modeling of parabolic leaf spring has been done in CATIA V5 and for analysis the model is imported in ANSYS-11 workbench. The finite element analysis (FEA of the leaf spring has been carried out by initially discretizing the model into finite number of elements and nodes and then applying the necessary boundary conditions. Maximum displacement, directional displacement, equivalent stress and weight of the assembly are the output targets of this analysis for comparison & validation of the work.

Well-posedness of nonlocal parabolic differential problems with dependent operators.

Science.gov (United States)

Ashyralyev, Allaberen; Hanalyev, Asker

2014-01-01

The nonlocal boundary value problem for the parabolic differential equation v'(t) + A(t)v(t) = f(t) (0 ≤ t ≤ T), v(0) = v(λ) + φ, 0 exact estimates in Hölder norms for the solution of two nonlocal boundary value problems for parabolic equations with dependent coefficients are established.

Reconciling consumption inequality with income inequality

NARCIS (Netherlands)

Lepetyuk, V.; Stoltenberg, C.A.

2012-01-01

The rise in consumption inequality in response to the increase in income inequality over the last three decades in the U.S. is puzzling to expected-utility-based incomplete market models. The two-sided lack of commitment models exhibit too little consumption inequality while the standard incomplete

Reconciling consumption inequality with income inequality

NARCIS (Netherlands)

Lepetyuk, V.; Stoltenberg, C.A.

2013-01-01

The rise in within-group consumption inequality in response to the increase in within-group income inequality over the last three decades in the U.S. is puzzling to expected-utility-based incomplete market models. The two-sided lack of commitment models exhibit too little consumption inequality

Income inequality and obesity prevalence among OECD countries.

Science.gov (United States)

Su, Dejun; Esqueda, Omar A; Li, Lifeng; Pagán, José A

2012-07-01

Using recent pooled data from the World Health Organization Global Infobase and the World Factbook compiled by the Central Intelligence Agency of the United States, this study assesses the relation between income inequality and obesity prevalence among 31 OECD countries through a series of bivariate and multivariate linear regressions. The United States and Mexico well lead OECD countries in both obesity prevalence and income inequality. A sensitivity analysis suggests that the inclusion or exclusion of these two extreme cases can fundamentally change the findings. When the two countries are included, the results reveal a positive correlation between income inequality and obesity prevalence. This correlation is more salient among females than among males. Income inequality alone is associated with 16% and 35% of the variations in male and female obesity rates, respectively, across OECD countries in 2010. Higher levels of income inequality in the 2005-2010 period were associated with a more rapid increase in obesity prevalence from 2002 to 2010. These associations, however, virtually disappear when the US and Mexico have been excluded from the analysis. Findings from this study underscore the importance of assessing the impact of extreme cases on the relation between income inequality and health outcomes. The potential pathways from income inequality to the alarmingly high rates of obesity in the cases of the US and Mexico warrant further research.

The less healthy urban population: income-related health inequality in China

Science.gov (United States)

2012-01-01

Background Health inequality has been recognized as a problem all over the world. In China, the poor usually have less access to healthcare than the better-off, despite having higher levels of need. Since the proportion of the Chinese population living in urban areas increased tremendously with the urbanization movements, attention has been paid to the association between urban/rural residence and population health. It is important to understand the variation in health across income groups, and in particular to take into account the effects of urban/rural residence on the degree of income-related health inequalities. Methods This paper empirically assesses the magnitude of rural/urban disparities in income-related adult health status, i.e., self-assessed health (SAH) and physical activity limitation, using Concentration Indices. It then uses decomposition methods to unravel the causes of inequalities and their variations across urban and rural populations. Data from the China Health and Nutrition Survey (CHNS) 2006 are used. Results The study finds that the poor are less likely to report their health status as “excellent or good” and are more likely to have physical activity limitation. Such inequality is more pronounced for the urban population than for the rural population. Results from the decomposition analysis suggest that, for the urban population, 76.47 per cent to 79.07 per cent of inequalities are driven by non-demographic/socioeconomic-related factors, among which income, job status and educational level are the most important factors. For the rural population, 48.19 per cent to 77.78 per cent of inequalities are driven by non-demographic factors. Income and educational attainment appear to have a prominent influence on inequality. Conclusion The findings suggest that policy targeting the poor, especially the urban poor, is needed in order to reduce health inequality. PMID:22989200

The less healthy urban population: income-related health inequality in China.

Science.gov (United States)

Yang, Wei; Kanavos, Panos

2012-09-18

Health inequality has been recognized as a problem all over the world. In China, the poor usually have less access to healthcare than the better-off, despite having higher levels of need. Since the proportion of the Chinese population living in urban areas increased tremendously with the urbanization movements, attention has been paid to the association between urban/rural residence and population health. It is important to understand the variation in health across income groups, and in particular to take into account the effects of urban/rural residence on the degree of income-related health inequalities. This paper empirically assesses the magnitude of rural/urban disparities in income-related adult health status, i.e., self-assessed health (SAH) and physical activity limitation, using Concentration Indices. It then uses decomposition methods to unravel the causes of inequalities and their variations across urban and rural populations. Data from the China Health and Nutrition Survey (CHNS) 2006 are used. The study finds that the poor are less likely to report their health status as "excellent or good" and are more likely to have physical activity limitation. Such inequality is more pronounced for the urban population than for the rural population. Results from the decomposition analysis suggest that, for the urban population, 76.47 per cent to 79.07 per cent of inequalities are driven by non-demographic/socioeconomic-related factors, among which income, job status and educational level are the most important factors. For the rural population, 48.19 per cent to 77.78 per cent of inequalities are driven by non-demographic factors. Income and educational attainment appear to have a prominent influence on inequality. The findings suggest that policy targeting the poor, especially the urban poor, is needed in order to reduce health inequality.

The less healthy urban population: income-related health inequality in China

Directory of Open Access Journals (Sweden)

Yang Wei

2012-09-01

Full Text Available Abstract Background Health inequality has been recognized as a problem all over the world. In China, the poor usually have less access to healthcare than the better-off, despite having higher levels of need. Since the proportion of the Chinese population living in urban areas increased tremendously with the urbanization movements, attention has been paid to the association between urban/rural residence and population health. It is important to understand the variation in health across income groups, and in particular to take into account the effects of urban/rural residence on the degree of income-related health inequalities. Methods This paper empirically assesses the magnitude of rural/urban disparities in income-related adult health status, i.e., self-assessed health (SAH and physical activity limitation, using Concentration Indices. It then uses decomposition methods to unravel the causes of inequalities and their variations across urban and rural populations. Data from the China Health and Nutrition Survey (CHNS 2006 are used. Results The study finds that the poor are less likely to report their health status as “excellent or good” and are more likely to have physical activity limitation. Such inequality is more pronounced for the urban population than for the rural population. Results from the decomposition analysis suggest that, for the urban population, 76.47 per cent to 79.07 per cent of inequalities are driven by non-demographic/socioeconomic-related factors, among which income, job status and educational level are the most important factors. For the rural population, 48.19 per cent to 77.78 per cent of inequalities are driven by non-demographic factors. Income and educational attainment appear to have a prominent influence on inequality. Conclusion The findings suggest that policy targeting the poor, especially the urban poor, is needed in order to reduce health inequality.

Variational formulation based analysis on growth of yield front in ...

African Journals Online (AJOL)

The present study investigates the growth of elastic-plastic front in rotating solid disks of non-uniform thickness having exponential and parabolic geometry variation. The problem is solved through an extension of a variational method in elastoplastic regime. The formulation is based on von-Mises yield criterion and linear ...

Is inequality at the heart of it? Cross-country associations of income inequality with cardiovascular diseases and risk factors.

Science.gov (United States)

Kim, Daniel; Kawachi, Ichiro; Hoorn, Stephen Vander; Ezzati, Majid

2008-04-01

Despite a number of cross-national studies that have examined the associations between income inequality and broad health outcomes such as life expectancy and all-cause mortality, investigations of the cross-country relations between income inequality and cardiovascular disease (CVD) morbidity, mortality, and risk factors are sparse. We analyzed the cross-national relations between income inequality and age-standardized mean body mass index (BMI), serum total cholesterol, systolic blood pressure (SBP), obesity prevalence, smoking impact ratio (SIR), and age-standardized and age-specific disability-adjusted life-years (DALYs) and mortality rates from coronary heart disease (CHD) and stroke, controlling for multiple country-level factors and specifying 5- to 10-year lag periods. In multivariable analyses primarily limited to industrialized countries, countries in the middle and highest (vs. lowest) tertiles of income inequality had higher absolute age-standardized obesity prevalences in both sexes. Higher income inequality was also related to higher mean SBP in both sexes, and higher SIR in women. In analyses of larger sets of countries with available data, positive associations were observed between higher income inequality and mean BMI, obesity prevalence, and CHD DALYs and mortality rates. Associations with stroke outcomes were inverse, yet became positive with the inclusion of eastern bloc and other countries in recent economic/political transition. China was also identified to be an influential data point, with the positive associations with stroke mortality rates becoming attenuated with its inclusion. Overall, our findings are compatible with harmful effects of income inequality at the national scale on CVD morbidity, mortality, and selected risk factors, particularly BMI/obesity. Future studies should consider income inequality as an independent contributor to variations in CVD burden globally.

Invariant features of spatial inequality in consumption: The case of India

Science.gov (United States)

Chatterjee, Arnab; Chakrabarti, Anindya S.; Ghosh, Asim; Chakraborti, Anirban; Nandi, Tushar K.

2016-01-01

We study the distributional features and inequality of consumption expenditure across India, for different states, castes, religion and urban-rural divide. We find that even though the aggregate measures of inequality are fairly diversified across states, the consumption distributions show near identical statistics, once properly normalized. This feature is seen to be robust with respect to variations in sociological and economic factors. We also show that state-wise inequality seems to be positively correlated with growth which is in accord with the traditional idea of Kuznets' curve. We present a brief model to account for the invariance found empirically and show that better but riskier technology draws can create a positive correlation between inequality and growth.

Parabolic Trough Solar Power for Competitive U.S. Markets

International Nuclear Information System (INIS)

Price, Henry W.

1998-01-01

Nine parabolic trough power plants located in the California Mojave Desert represent the only commercial development of large-scale solar power plants to date. Although all nine plants continue to operate today, no new solar power plants have been completed since 1990. Over the last several years, the parabolic trough industry has focused much of its efforts on international market opportunities. Although the power market in developing countries appears to offer a number of opportunities for parabolic trough technologies due to high growth and the availability of special financial incentives for renewables, these markets are also plagued with many difficulties for developers. In recent years, there has been some renewed interest in the U.S. domestic power market as a result of an emerging green market and green pricing incentives. Unfortunately, many of these market opportunities and incentives focus on smaller, more modular technologies (such as photovoltaics or wind power), and as a result they tend to exclude or are of minimum long-term benefit to large-scale concentrating solar power technologies. This paper looks at what is necessary for large-scale parabolic trough solar power plants to compete with state-of-the-art fossil power technology in a competitive U.S. power market

Inequality in health versus inequality in lifestyle choices

Directory of Open Access Journals (Sweden)

Arnstein Øvrum

2015-10-01

Full Text Available Repeated Norwegian cross-sectional data for the period 2005 to 2011 are used to compare sources of inequality in health, as represented by self-assessed health and obesity, with sources of inequality in lifestyles that are central to the production of health, as represented by physical activity, cigarette smoking and dietary behavior. Sources of overall inequality and socioeconomic inequality in these lifestyle and health indicators are compared by estimating probit models, and by decomposing the explained part of the associated Gini and concentration indices with respect to education and income. As potential sources of inequality, we consider education, income, occupation, age, gender, marital status, psychological traits and childhood circumstances. Our results suggest that sources of inequality in health are not necessarily representative of sources of inequality in underlying lifestyles. While education is generally an important source of overall inequality in both lifestyles and health, income is unimportant in all lifestyle indicators except physical activity. In several cases, education and income are clearly outranked by other factors in terms of explaining overall inequality, such as gender in eating fruits and vegetables and age in fish consumption. These results suggest that it is important to decompose both overall inequality and socioeconomic inequality in different lifestyle and health indicators. In indicators where other factors than education and income are clearly most important, policy makers should consider to target these factors to efficiently improve overall population health.

Use of a Parabolic Microphone to Detect Hidden Subjects in Search and Rescue.

Science.gov (United States)

Bowditch, Nathaniel L; Searing, Stanley K; Thomas, Jeffrey A; Thompson, Peggy K; Tubis, Jacqueline N; Bowditch, Sylvia P

2018-03-01

This study compares a parabolic microphone to unaided hearing in detecting and comprehending hidden callers at ranges of 322 to 2510 m. Eight subjects were placed 322 to 2510 m away from a central listening point. The subjects were concealed, and their calling volume was calibrated. In random order, subjects were asked to call the name of a state for 5 minutes. Listeners with parabolic microphones and others with unaided hearing recorded the direction of the call (detection) and name of the state (comprehension). The parabolic microphone was superior to unaided hearing in both detecting subjects and comprehending their calls, with an effect size (Cohen's d) of 1.58 for detection and 1.55 for comprehension. For each of the 8 hidden subjects, there were 24 detection attempts with the parabolic microphone and 54 to 60 attempts by unaided listeners. At the longer distances (1529-2510 m), the parabolic microphone was better at detecting callers (83% vs 51%; P<0.00001 by χ 2 ) and comprehension (57% vs 12%; P<0.00001). At the shorter distances (322-1190 m), the parabolic microphone offered advantages in detection (100% vs 83%; P=0.000023) and comprehension (86% vs 51%; P<0.00001), although not as pronounced as at the longer distances. Use of a 66-cm (26-inch) parabolic microphone significantly improved detection and comprehension of hidden calling subjects at distances between 322 and 2510 m when compared with unaided hearing. This study supports the use of a parabolic microphone in search and rescue to locate responsive subjects in favorable weather and terrain. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Income Inequality and Intergenerational Income Mobility in the United States

Science.gov (United States)

Bloome, Deirdre

2015-01-01

Is there a relationship between family income inequality and income mobility across generations in the United States? As family income inequality rose in the United States, parental resources available for improving children’s health, education, and care diverged. The amount and rate of divergence also varied across US states. Researchers and policy analysts have expressed concern that relatively high inequality might be accompanied by relatively low mobility, tightening the connection between individuals’ incomes during childhood and adulthood. Using data from the Panel Study of Income Dynamics, the National Longitudinal Survey of Youth, and various government sources, this paper exploits state and cohort variation to estimate the relationship between inequality and mobility. Results provide very little support for the hypothesis that inequality shapes mobility in the United States. The inequality children experienced during youth had no robust association with their economic mobility as adults. Formal analysis reveals that offsetting effects could underlie this result. In theory, mobility-enhancing forces may counterbalance mobility-reducing effects. In practice, the results suggest that in the US context, the intergenerational transmission of income may not be very responsive to changes in inequality. PMID:26388653

Valuation of American Call Option Considering Uncertain Volatility

Czech Academy of Sciences Publication Activity Database

Hlaváček, Ivan

2010-01-01

Roč. 2, č. 2 (2010), s. 211-221 ISSN 2070-0733 R&D Projects: GA AV ČR(CZ) IAA100190803 Institutional research plan: CEZ:AV0Z10190503 Keywords : American options * parabolic variational inequality * uncertain parameter Subject RIV: BA - General Mathematics Impact factor: 0.510, year: 2010 http://www.global-sci.org/aamm/readabs.php?vol=2&no=2&doc=211&year=2010&ppage=221

Sasakian and Parabolic Higgs Bundles

Science.gov (United States)

Biswas, Indranil; Mj, Mahan

2018-03-01

Let M be a quasi-regular compact connected Sasakian manifold, and let N = M/ S 1 be the base projective variety. We establish an equivalence between the class of Sasakian G-Higgs bundles over M and the class of parabolic (or equivalently, ramified) G-Higgs bundles over the base N.

Do differences in the administrative structure of populations confound comparisons of geographic health inequalities?

LENUS (Irish Health Repository)

Jackson, Andrew L

2010-08-18

Abstract Background Geographical health inequalities are naturally described by the variation in health outcomes between areas (e.g. mortality rates). However, comparisons made between countries are hampered by our lack of understanding of the effect of the size of administrative units, and in particular the modifiable areal unit problem. Our objective was to assess how differences in geographic and administrative units used for disseminating data affect the description of health inequalities. Methods Retrospective study of standard populations and deaths aggregated by administrative regions within 20 European countries, 1990-1991. Estimated populations and deaths in males aged 0-64 were in 5 year age bands. Poisson multilevel modelling was conducted of deaths as standardised mortality ratios. The variation between regions within countries was tested for relationships with the mean region population size and the unequal distribution of populations within each country measured using Gini coefficients. Results There is evidence that countries whose regions vary more in population size show greater variation and hence greater apparent inequalities in mortality counts. The Gini coefficient, measuring inequalities in population size, ranged from 0.1 to 0.5 between countries; an increase of 0.1 was accompanied by a 12-14% increase in the standard deviation of the mortality rates between regions within a country. Conclusions Apparently differing health inequalities between two countries may be due to differences in geographical structure per se, rather than having any underlying epidemiological cause. Inequalities may be inherently greater in countries whose regions are more unequally populated.

Income related inequalities in avoidable mortality in Norway: A population-based study using data from 1994-2011.

Science.gov (United States)

Kinge, Jonas Minet; Vallejo-Torres, Laura; Morris, Stephen

2015-07-01

The aim of this study was to measure income-related inequalities in avoidable, amenable and preventable mortality in Norway over the period 1994-2011. We undertook a register-based population study of Norwegian residents aged 18-65 years between 1994 and 2011, using data from the Norwegian Income Register and the Cause of Death Registry. Concentration indices were used to measure income-related inequalities in avoidable, amenable and preventable mortality for each year. We compared the trend in income-related inequality in avoidable mortality with the trend in income inequality, measured by the Gini coefficient for income. Avoidable, amenable and preventable deaths in Norway have declined over time. There were persistent pro-poor socioeconomic inequalities in avoidable, amenable and preventable mortality, and the degree of inequality was larger in preventable mortality than in amenable mortality throughout the period. The income-avoidable mortality association was positively correlated with income inequalities in avoidable mortality over time. There was little or no relationship between variations in the Gini coefficient due to tax reforms and socioeconomic inequalities in avoidable mortality. Income-related inequalities in avoidable, amenable and preventable mortality have remained relatively constant between 1994 and 2011 in Norway. They were mainly correlated with the relationship between income and avoidable mortality rather than with variations in the Gini coefficient of income inequality. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

A Two-Species Cooperative Lotka-Volterra System of Degenerate Parabolic Equations

Directory of Open Access Journals (Sweden)

Jiebao Sun

2011-01-01

parabolic equations. We are interested in the coexistence of the species in a bounded domain. We establish the existence of global generalized solutions of the initial boundary value problem by means of parabolic regularization and also consider the existence of the nontrivial time-periodic solution for this system.

Economic inequality is linked to biased self-perception.

Science.gov (United States)

Loughnan, Steve; Kuppens, Peter; Allik, Jüri; Balazs, Katalin; de Lemus, Soledad; Dumont, Kitty; Gargurevich, Rafael; Hidegkuti, Istvan; Leidner, Bernhard; Matos, Lennia; Park, Joonha; Realo, Anu; Shi, Junqi; Sojo, Victor Eduardo; Tong, Yuk-Yue; Vaes, Jeroen; Verduyn, Philippe; Yeung, Victoria; Haslam, Nick

2011-10-01

People's self-perception biases often lead them to see themselves as better than the average person (a phenomenon known as self-enhancement). This bias varies across cultures, and variations are typically explained using cultural variables, such as individualism versus collectivism. We propose that socioeconomic differences among societies--specifically, relative levels of economic inequality--play an important but unrecognized role in how people evaluate themselves. Evidence for self-enhancement was found in 15 diverse nations, but the magnitude of the bias varied. Greater self-enhancement was found in societies with more income inequality, and income inequality predicted cross-cultural differences in self-enhancement better than did individualism/collectivism. These results indicate that macrosocial differences in the distribution of economic goods are linked to microsocial processes of perceiving the self.

Nanofocusing Parabolic Refractive X-Ray Lenses

International Nuclear Information System (INIS)

Schroer, C.G.; Kuhlmann, M.; Hunger, U.T.; Guenzler, T.F.; Kurapova, O.; Feste, S.; Lengeler, B.; Drakopoulos, M.; Somogyi, A.; Simionovici, A. S.; Snigirev, A.; Snigireva, I.

2004-01-01

Parabolic refractive x-ray lenses with short focal distance can generate intensive hard x-ray microbeams with lateral extensions in the 100nm range even at short distance from a synchrotron radiation source. We have fabricated planar parabolic lenses made of silicon that have a focal distance in the range of a few millimeters at hard x-ray energies. In a crossed geometry, two lenses were used to generate a microbeam with a lateral size of 330nm by 110nm at 25keV in a distance of 41.8m from the synchrotron radiation source. First microdiffraction and fluorescence microtomography experiments were carried out with these lenses. Using diamond as lens material, microbeams with lateral size down to 20nm and below are conceivable in the energy range from 10 to 100keV

Does a Rise in Income Inequality Lead to Rises in Transportation Inequality and Mobility Practice Inequality?

Directory of Open Access Journals (Sweden)

Joko Purwanto

2016-06-01

Full Text Available Social and economic inequalities have sharpened in the late 20th century. During this period, Europe has witnessed a rising unemployment rate, a declining wages for the least qualified workers, a slowing of income growth, and an increasing gap between the richest and the poorest. Based on the hypothesis of the relation between socio-economic condition and mobility behaviour, it is necessary to ask how these socio-economic inequalities manifest themselves in transportation: does a rise in income inequality lead to a rise in transportation inequality and mobility practice inequality? This question is particularly relevant today as some European countries are facing high socio-economic inequalities following the financial crisis that started in 2008. Using results from transport, car ownership and mobility surveys as well as household surveys from the Paris (Île-de-France region between eighties and late nineties, this paper tries to answer this question. The results show how inequalities in transportation and mobility practice have decreased during the period in spite of an increase in income inequalities. We find that the evolution of socio-economic inequality, most specifically income inequality was simply one of the determining factors of the evolution of inequalities in transportation and mobility practice. In fact, the most important role in that evolution is not played by the evolution of income inequality but by the evolution of elasticity between transportation and income. Reducing the effects of this elasticity should be the main target of transport policies to diminish inequality in transportation and mobility practice.

Monitoring gender remuneration inequalities in academia using ...

African Journals Online (AJOL)

... age, research output and qualifications are related to remuneration. The CVA biplots show narrowing, widening and constant gender remuneration gaps in diffferent faculties. Keywords: alpha-bag, academia, biplot, canonical variate analysis, gender inequality, multivariate, wage gap. ORiON Vol. 24 (1) 2008: pp. 49-73 ...

Explicit nonlinear finite element geometric analysis of parabolic leaf springs under various loads.

Science.gov (United States)

Kong, Y S; Omar, M Z; Chua, L B; Abdullah, S

2013-01-01

This study describes the effects of bounce, brake, and roll behavior of a bus toward its leaf spring suspension systems. Parabolic leaf springs are designed based on vertical deflection and stress; however, loads are practically derived from various modes especially under harsh road drives or emergency braking. Parabolic leaf springs must sustain these loads without failing to ensure bus and passenger safety. In this study, the explicit nonlinear dynamic finite element (FE) method is implemented because of the complexity of experimental testing A series of load cases; namely, vertical push, wind-up, and suspension roll are introduced for the simulations. The vertical stiffness of the parabolic leaf springs is related to the vehicle load-carrying capability, whereas the wind-up stiffness is associated with vehicle braking. The roll stiffness of the parabolic leaf springs is correlated with the vehicle roll stability. To obtain a better bus performance, two new parabolic leaf spring designs are proposed and simulated. The stress level during the loadings is observed and compared with its design limit. Results indicate that the newly designed high vertical stiffness parabolic spring provides the bus a greater roll stability and a lower stress value compared with the original design. Bus safety and stability is promoted, as well as the load carrying capability.

Explicit Nonlinear Finite Element Geometric Analysis of Parabolic Leaf Springs under Various Loads

Directory of Open Access Journals (Sweden)

Y. S. Kong

2013-01-01

Full Text Available This study describes the effects of bounce, brake, and roll behavior of a bus toward its leaf spring suspension systems. Parabolic leaf springs are designed based on vertical deflection and stress; however, loads are practically derived from various modes especially under harsh road drives or emergency braking. Parabolic leaf springs must sustain these loads without failing to ensure bus and passenger safety. In this study, the explicit nonlinear dynamic finite element (FE method is implemented because of the complexity of experimental testing A series of load cases; namely, vertical push, wind-up, and suspension roll are introduced for the simulations. The vertical stiffness of the parabolic leaf springs is related to the vehicle load-carrying capability, whereas the wind-up stiffness is associated with vehicle braking. The roll stiffness of the parabolic leaf springs is correlated with the vehicle roll stability. To obtain a better bus performance, two new parabolic leaf spring designs are proposed and simulated. The stress level during the loadings is observed and compared with its design limit. Results indicate that the newly designed high vertical stiffness parabolic spring provides the bus a greater roll stability and a lower stress value compared with the original design. Bus safety and stability is promoted, as well as the load carrying capability.

Social justice, epidemiology and health inequalities.

Science.gov (United States)

Marmot, Michael

2017-07-01

A lifetime spent studying how social determinants of health lead to health inequalities has clarified many issues. First is that social stratification is an appropriate topic of study for epidemiologists. To ignore it would be to ignore a major source of variation in health in society. Not only is the social gradient in health appropriate to study but we have made progress both in understanding its causes and what can be done to address them. Post-modern 'critical theory' raises questions about the social construction of science. Given the attack on science by politicians of bad faith, it is important to recognise that epidemiology and public health have a crucial role to play in providing evidence to improve health of society and reduce inequalities. Evidence gives grounds for optimism that progress can be made both in improving the health of the worst-off in society and narrowing health inequalities. Theoretical debates about 'inequality of what' have been helpful in clarifying theories that drive further gathering of evidence. While it is important to consider alternative explanations of the social gradient in health-principal among them reverse causation-evidence strongly supports social causation. Social action is by its nature political. It is, though, a vital function to provide the evidence that underpins action.

An introduction to geometric theory of fully nonlinear parabolic equations

International Nuclear Information System (INIS)

Lunardi, A.

1991-01-01

We study a class of nonlinear evolution equations in general Banach space being an abstract version of fully nonlinear parabolic equations. In addition to results of existence, uniqueness and continuous dependence on the data, we give some qualitative results about stability of the stationary solutions, existence and stability of the periodic orbits. We apply such results to some parabolic problems arising from combustion theory. (author). 24 refs

Vector optimization set-valued and variational analysis

CERN Document Server

Chen, Guang-ya; Yang, Xiaogi

2005-01-01

This book is devoted to vector or multiple criteria approaches in optimization. Topics covered include: vector optimization, vector variational inequalities, vector variational principles, vector minmax inequalities and vector equilibrium problems. In particular, problems with variable ordering relations and set-valued mappings are treated. The nonlinear scalarization method is extensively used throughout the book to deal with various vector-related problems. The results presented are original and should be interesting to researchers and graduates in applied mathematics and operations research

Nonimaging secondary concentrators for large rim angle parabolic troughs with tubular absorbers.

Science.gov (United States)

Ries, H; Spirkl, W

1996-05-01

For parabolic trough solar collectors with tubular absorbers, we design new tailored secondary concentrators. The design is applicable for any rim angle of a parabolic reflector. With the secondary, the concentration can be increased by a factor of more than 2 with a compact secondary reflector consisting of a single piece, even for the important case of a rim angle of 90 deg. The parabolic reflector can be used without changes; the reduced absorber is still tubular but smaller than the original absorber and slightly displaced toward the primary.

Canonical generators of the cohomology of moduli of parabolic bundles on curves

International Nuclear Information System (INIS)

Biswas, I.; Raghavendra, N.

1994-11-01

We determine generators of the rational cohomology algebras of moduli spaces of parabolic vector bundles on a curve, under some 'primality' conditions on the parabolic datum. These generators are canonical in a precise sense. Our results are new even for usual vector bundles (i.e., vector bundles without parabolic structure) whose rank is greater than 2 and is coprime to the degree; in this case, they are generalizations of a theorem of Newstead on the moduli of vector bundles of rank 2 and odd degree. (author). 11 refs

On the behaviour of solutions of parabolic equations for large values of time

International Nuclear Information System (INIS)

Denisov, V N

2005-01-01

This paper is a survey of classical and new results on stabilization of solutions of the Cauchy problem and mixed problems for second-order linear parabolic equations. Proofs are given for some new results about exact sufficient conditions on the behaviour of lower-order coefficients of the parabolic equation; these conditions ensure stabilization of a solution of the Cauchy problem for the parabolic equation in the class of bounded or increasing initial functions

Educational Inequality and Income Inequality: An Empirical Study on China

Science.gov (United States)

Yang, Jun; Huang, Xiao; Li, Xiaoyu

2009-01-01

Based on the endogenous growth theory, this paper uses the Gini coefficient to measure educational inequality and studies the empirical relationship between educational inequality and income inequality through a simultaneous equation model. The results show that: (1) Income inequality leads to educational inequality while the reduction of…

Monitoring gender remuneration inequalities in academia using ...

African Journals Online (AJOL)

alpha-bag, academia, biplot, canonical variate analysis, gender inequality, multivariate, .... decreased by 0.3% annually in the USA, 0.8% in Canada, Australia and New .... the University must provide competitive remuneration for staff with ..... on or off. In practice, differences between males and females can thus easily be ...

Measurement of gender inequality in neighbourhoods of Québec, Canada

Directory of Open Access Journals (Sweden)

Tamambang Lum

2011-11-01

Full Text Available Abstract Introduction Few studies have measured gender inequality at levels lower than the country. We sought to develop neighbourhood indicators of gender inequality, and assess their ability to capture variability in gender inequality across Québec, Canada. Methods Aggregate 2001 census data for 11,564 neighbourhoods were obtained for men and women. Twelve indicators of gender inequality representing demographic/household characteristics, education, income, work/leisure, and political participation were selected. Neighbourhood-level gender inequality scores were computed for each indicator, and examined across parts of Québec (metropolitan areas, mid-sized cities, rural areas. Monte Carlo simulations were used to assess the ability of indicators to capture heterogeneity in gender inequality across neighbourhoods. Results Male-dominant neighbourhood-level gender inequality tended to be present for average employment income, labour force participation, employment rate, and employment in managerial positions. Female-dominant gender inequality tended to be present for divorce, single-headed households, and participation in unpaid housework, child and elderly care. Neighbourhood-level gender inequality tended to vary across metropolitan areas, mid-sized cities, and rural areas. Gender inequality scores also varied within these geographic areas. For example, there was greater income-related gender inequality in high than low income neighbourhoods. Monte Carlo simulations suggested that the variation in gender inequality across neighbourhoods was greater than expected with chance alone. Conclusion Neighbourhood-level gender inequality tended to be present in Québec, and varied across parts of the province. Greater awareness of and research on neighbourhood-level gender inequality may be warranted to inform gender policies in Québec and other nations.

Artificial neural networks approach on solar parabolic dish cooker

International Nuclear Information System (INIS)

Lokeswaran, S.; Eswaramoorthy, M.

2011-01-01

This paper presents heat transfer analysis of solar parabolic dish cooker using Artificial Neural Network (ANN). The objective of this study to envisage thermal performance parameters such as receiver plate and pot water temperatures of the solar parabolic dish cooker by using the ANN for experimental data. An experiment is conducted under two cases (1) cooker with plain receiver and (2) cooker with porous receiver. The Back Propagation (BP) algorithm is used to train and test networks and ANN predictions are compared with experimental results. Different network configurations are studied by the aid of searching a relatively better network for prediction. The results showed a good regression analysis with the correlation coefficients in the range of 0.9968-0.9992 and mean relative errors (MREs) in the range of 1.2586-4.0346% for the test data set. Thus ANN model can successfully be used for the prediction of the thermal performance parameters of parabolic dish cooker with reasonable degree of accuracy. (authors)

Variational principles for nonpotential operators

CERN Document Server

Filippov, V M

1989-01-01

This book develops a variational method for solving linear equations with B-symmetric and B-positive operators and generalizes the method to nonlinear equations with nonpotential operators. The author carries out a constructive extension of the variational method to "nonvariational" equations (including parabolic equations) in classes of functionals which differ from the Euler-Lagrange functionals. In this connection, some new functions spaces are considered. Intended for mathematicians working in the areas of functional analysis and differential equations, this book would also prove useful for researchers in other areas and students in advanced courses who use variational methods in solving linear and nonlinear boundary value problems in continuum mechanics and theoretical physics.

Who are Your Joneses? Socio-Specific Income Inequality and Trust.

Science.gov (United States)

Stephany, Fabian

2017-01-01

Trust is a good approach to explain the functioning of markets, institutions or society as a whole. It is a key element in almost every commercial transaction over time and might be one of the main explanations of economic success and development. Trust diminishes the more we perceive others to have economically different living realities. In most of the relevant contributions, scholars have taken a macro perspective on the inequality-trust linkage, with an aggregation of both trust and inequality on a country level. However, patterns of within-country inequality and possibly influential determinants, such as perception and socioeconomic reference, remained undetected. This paper offers the opportunity to look at the interplay between inequality and trust at a more refined level. A measure of (generalized) trust emerges from ESS 5 survey which asks "... generally speaking, would you say that most people can be trusted, or that you can't be too careful in dealing with people? ". With the use of 2009 EU-SILC data, measurements of income inequality are developed for age-specific groups of society in 22 countries. A sizable variation in inequality measures can be noticed. Even in low inequality countries, like Sweden, income imbalances within certain age groups have the potential to undermine social trust.

Change in Wage Inequality in the Czech Republic

DEFF Research Database (Denmark)

Eriksson, Tor Viking; Pytlikova, Mariola; Warzynski, Frederic

gender inequality, decreased returns to human capital, especially to education. Moreover, exploiting the linked employer-employee character of the data set, we document changes in within-firm wage dispersion and short-term variations around a constant level of between-firm dispersion. Next, we...

Regional income inequality model based on theil index decomposition and weighted variance coeficient

Science.gov (United States)

Sitepu, H. R.; Darnius, O.; Tambunan, W. N.

2018-03-01

Regional income inequality is an important issue in the study on economic development of a certain region. Rapid economic development may not in accordance with people’s per capita income. The method of measuring the regional income inequality has been suggested by many experts. This research used Theil index and weighted variance coefficient in order to measure the regional income inequality. Regional income decomposition which becomes the productivity of work force and their participation in regional income inequality, based on Theil index, can be presented in linear relation. When the economic assumption in j sector, sectoral income value, and the rate of work force are used, the work force productivity imbalance can be decomposed to become the component in sectors and in intra-sectors. Next, weighted variation coefficient is defined in the revenue and productivity of the work force. From the quadrate of the weighted variation coefficient result, it was found that decomposition of regional revenue imbalance could be analyzed by finding out how far each component contribute to regional imbalance which, in this research, was analyzed in nine sectors of economic business.

Parabolic dish collectors - A solar option

Science.gov (United States)

Truscello, V. C.

1981-05-01

A description is given of several parabolic-dish high temperature solar thermal systems currently undergoing performance trials. A single parabolic dish has the potential for generating 20 to 30 kW of electricity with fluid temperatures from 300 to 1650 C. Each dish is a complete power-producing unit, and may function either independently or as part of a group of linked modules. The two dish designs under consideration are of 11 and 12 meter diameters, yielding receiver operating temperatures of 925 and 815 C, respectively. The receiver designs described include (1) an organic working fluid (toluene) Rankine cycle engine; (2) a Brayton open cycle unit incorporating a hybrid combustion chamber and nozzle and a shaft-coupled permanent magnet alternator; and (3) a modified Stirling cycle device originally designed for automotive use. Also considered are thermal buffer energy storage and thermochemical transport and storage.

Spheroidal corrections to the spherical and parabolic bases of the hydrogen atom

International Nuclear Information System (INIS)

Mardyan, L.G.; Pogosyan, G.S.; Sisakyan, A.N.

1986-01-01

This paper introduces the bases of the hydrogen atom and obtains recursion relations that determine the expansion of the spheroidal basis with respect to its parabolic basis. The leading spheroidal corrections to the spherical and parabolic bases are calculated by perturbation theory

Some integral representations and limits for (products of) the parabolic cylinder function

NARCIS (Netherlands)

Veestraeten, D.

2016-01-01

Recently, [Veestraeten D. On the inverse transform of Laplace transforms that contain (products of) the parabolic cylinder function. Integr Transf Spec F 2015;26:859-871] derived inverse Laplace transforms for Laplace transforms that contain products of two parabolic cylinder functions by exploiting

Area-level income inequality and oral health among Australian adults-A population-based multilevel study.

Science.gov (United States)

Singh, Ankur; Harford, Jane; Antunes, José Leopoldo Ferreira; Peres, Marco A

2018-01-01

A lack of evidence exists on the association between area-level income inequality and oral health within Australia. This study examined associations between area-level income inequality and oral health outcomes (inadequate dentition (income inequality and oral health outcomes according to area-level mean income were also assessed. Finally, household-income gradients in oral health outcomes according to area-level income inequality were compared. For the analyses, data on Australian dentate adults (n = 5,165 nested in 435 Local Government Areas (LGAs)) was obtained from the National Dental Telephone Interview Survey-2013. Multilevel multivariable logistic regression models with random intercept and fixed slopes were fitted to test associations between area-level income inequality and oral health outcomes, examine variations in associations according to area-level mean income, and examine variations in household-income gradients in outcomes according to area-level income inequality. Covariates included age, sex, LGA-level mean weekly household income, geographic remoteness and household income. LGA-level income inequality was not associated with poor self-rated oral health and inversely associated with inadequate dentition (OR: 0.64; 95% CI: 0.48, 0.87) after adjusting for covariates. Inverse association between income inequality and inadequate dentition at the individual level was limited to LGAs within the highest tertile of mean weekly household income. Household income gradients in both outcomes showed poorer oral health at lower levels of household income. The household income gradients for inadequate dentition varied according to the LGA-level income inequality. Findings suggest that income inequality at the LGA-level in Australia is not positively associated with poorer oral health outcomes. Inverse association between income inequality and inadequate dentition is likely due to the contextual differences between Australia and other high-income countries.

Area-level income inequality and oral health among Australian adults—A population-based multilevel study

Science.gov (United States)

2018-01-01

Background A lack of evidence exists on the association between area-level income inequality and oral health within Australia. This study examined associations between area-level income inequality and oral health outcomes (inadequate dentition (income inequality and oral health outcomes according to area-level mean income were also assessed. Finally, household-income gradients in oral health outcomes according to area-level income inequality were compared. Methods For the analyses, data on Australian dentate adults (n = 5,165 nested in 435 Local Government Areas (LGAs)) was obtained from the National Dental Telephone Interview Survey-2013. Multilevel multivariable logistic regression models with random intercept and fixed slopes were fitted to test associations between area-level income inequality and oral health outcomes, examine variations in associations according to area-level mean income, and examine variations in household-income gradients in outcomes according to area-level income inequality. Covariates included age, sex, LGA-level mean weekly household income, geographic remoteness and household income. Results LGA-level income inequality was not associated with poor self-rated oral health and inversely associated with inadequate dentition (OR: 0.64; 95% CI: 0.48, 0.87) after adjusting for covariates. Inverse association between income inequality and inadequate dentition at the individual level was limited to LGAs within the highest tertile of mean weekly household income. Household income gradients in both outcomes showed poorer oral health at lower levels of household income. The household income gradients for inadequate dentition varied according to the LGA-level income inequality. Conclusion Findings suggest that income inequality at the LGA-level in Australia is not positively associated with poorer oral health outcomes. Inverse association between income inequality and inadequate dentition is likely due to the contextual differences between Australia

Decomposing income-related inequality in cervical screening in 67 countries.

Science.gov (United States)

McKinnon, Brittany; Harper, Sam; Moore, Spencer

2011-04-01

The development of successful policies to reduce income-related inequalities in cervical cancer screening rates requires an understanding of the reasons why low-income women are less likely to be screened. We sought to identify important determinants contributing to inequality in cervical screening rates. We analyzed data from 92,541 women aged 25-64 years, who participated in the World Health Survey in 2002-2003. Income-related inequality in Pap screening was measured using the concentration index (CI). Using a decomposition method for the CI, we quantified the contribution to inequality of age, education level, marital status, urbanicity and recent health-care need. There was substantial heterogeneity in the contributions of different determinants to inequality among countries. Education generally made the largest contribution (median = 15%, interquartile range [IQR] = 23%), although this varied widely even within regions (e.g., 5% in Austria, 28% in Hungary). The contribution of rural residence was greatest in African countries (median = 10%, IQR = 13%); however, there was again substantial within-region variation (e.g., 26% in Zambia, 2% in Kenya). Considerable heterogeneity in the contributions of screening determinants among countries suggests interventions to reduce screening inequalities may require country-specific approaches.

Maximum principles for boundary-degenerate linear parabolic differential operators

OpenAIRE

Feehan, Paul M. N.

2013-01-01

We develop weak and strong maximum principles for boundary-degenerate, linear, parabolic, second-order partial differential operators, $Lu := -u_t-\\tr(aD^2u)-\\langle b, Du\\rangle + cu$, with \\emph{partial} Dirichlet boundary conditions. The coefficient, $a(t,x)$, is assumed to vanish along a non-empty open subset, $\\mydirac_0!\\sQ$, called the \\emph{degenerate boundary portion}, of the parabolic boundary, $\\mydirac!\\sQ$, of the domain $\\sQ\\subset\\RR^{d+1}$, while $a(t,x)$ may be non-zero at po...

Irreversible thermodynamics, parabolic law and self-similar state in grain growth

International Nuclear Information System (INIS)

Rios, P.R.

2004-01-01

The formalism of the thermodynamic theory of irreversible processes is applied to grain growth to investigate the nature of the self-similar state and its corresponding parabolic law. Grain growth does not reach a steady state in the sense that the entropy production remains constant. However, the entropy production can be written as a product of two factors: a scale factor that tends to zero for long times and a scaled entropy production. It is suggested that the parabolic law and the self-similar state may be associated with the minimum of this scaled entropy production. This result implies that the parabolic law and the self-similar state have a sound irreversible thermodynamical basis

Performance Analysis of Fractional-Order PID Controller for a Parabolic Distributed Solar Collector

KAUST Repository

Elmetennani, Shahrazed

2017-09-01

This paper studies the performance of a fractional-order proportional integral derivative (FOPID) controller designed for parabolic distributed solar collectors. The control problem addressed in concentrated solar collectors aims at forcing the produced heat to follow a desired reference despite the unevenly varying solar irradiance. In addition to the unpredictable variations of the energy source, the parabolic solar collectors are subject to inhomogeneous distributed efficiency parameters affecting the heat production. The FOPID controller is well known for its simplicity with better tuning flexibility along with robustness with respect to disturbances. Thus, we propose a control strategy based on FOPID to achieve the control objectives. First, the FOPID controller is designed based on a linear approximate model describing the system dynamics under nominal working conditions. Then, the FOPID gains and differentiation orders are optimally tuned in order to fulfill the robustness design specifications by solving a nonlinear optimization problem. Numerical simulations are carried out to evaluate the performance of the proposed FOPID controller. A comparison to the robust integer order PID is also provided. Robustness tests are performed for the nominal model to show the effectiveness of the FOPID. Furthermore, the proposed FOPID is numerically tested to control the distributed solar collector under real working conditions.

A Two-Species Cooperative Lotka-Volterra System of Degenerate Parabolic Equations

OpenAIRE

Sun, Jiebao; Zhang, Dazhi; Wu, Boying

2011-01-01

We consider a cooperating two-species Lotka-Volterra model of degenerate parabolic equations. We are interested in the coexistence of the species in a bounded domain. We establish the existence of global generalized solutions of the initial boundary value problem by means of parabolic regularization and also consider the existence of the nontrivial time-periodic solution for this system.

Analysis of spin crossover nanochains using parabolic approximation in the framework of atom–phonon coupling model

Energy Technology Data Exchange (ETDEWEB)

Chiruta, D. [Groupe d’Etude de la Matiere Condensee (GEMAC), UMR 8635, CNRS, Universite de Versailles Saint Quentin, 45, Avenue des Etats-Unis, 78035 Versailles (France); Faculty of Electrical Engineering and Computer Science & Advanced Materials and Nanotechnology Laboratory (AMNOL), Stefan cel Mare University, Suceava 720229 (Romania); Jureschi, C.-M. [Faculty of Electrical Engineering and Computer Science & Advanced Materials and Nanotechnology Laboratory (AMNOL), Stefan cel Mare University, Suceava 720229 (Romania); Laboratoire d’Ingenierie des Systemes de Versailles (LISV), EA 4048, CNRS, Universite de Versailles Saint Quentin, 45, Avenue des Etats-Unis, 78035 Versailles (France); Linares, J., E-mail: jorge.linares@uvsq.fr [Groupe d’Etude de la Matiere Condensee (GEMAC), UMR 8635, CNRS, Universite de Versailles Saint Quentin, 45, Avenue des Etats-Unis, 78035 Versailles (France); Nasser, J. [Laboratoire d’Ingenierie des Systemes de Versailles (LISV), EA 4048, CNRS, Universite de Versailles Saint Quentin, 45, Avenue des Etats-Unis, 78035 Versailles (France); Rotaru, A. [Faculty of Electrical Engineering and Computer Science & Advanced Materials and Nanotechnology Laboratory (AMNOL), Stefan cel Mare University, Suceava 720229 (Romania)

2015-11-01

In this paper the atom–phonon coupling model is applied to explain and illustrate the behavior of a linear chain of molecules in the case of spin crossover (SCO) compounds. It is well known that besides the system's cooperativity which influences the hysteretic behavior of SCO complexes, the size of the system also plays a determinant role. The system's properties are analyzed using a parabolic algorithm as a new method proposed herein for the first time in order to take into account the phonon contribution. Based on exact calculations, this method is closer to the reality and more efficient than the mean-field approximation (MFA). In particular, both the parabolic algorithm and the dynamic-matrix method are tested and compared and it is shown from the analysis of the system's behavior that large size can be handled without generating all the system states. We also analyzed the role of degeneracy, and the thermal variation of both the entropy and heat capacity in the ferromagnetic-like coupling case.

The dynamics of parabolic flight: Flight characteristics and passenger percepts

Science.gov (United States)

Karmali, Faisal; Shelhamer, Mark

2008-09-01

Flying a parabolic trajectory in an aircraft is one of the few ways to create freefall on Earth, which is important for astronaut training and scientific research. Here we review the physics underlying parabolic flight, explain the resulting flight dynamics, and describe several counterintuitive findings, which we corroborate using experimental data. Typically, the aircraft flies parabolic arcs that produce approximately 25 s of freefall (0 g) followed by 40 s of enhanced force (1.8 g), repeated 30-60 times. Although passengers perceive gravity to be zero, in actuality acceleration, and not gravity, has changed, and thus we caution against the terms "microgravity" and "zero gravity." Despite the aircraft trajectory including large (45°) pitch-up and pitch-down attitudes, the occupants experience a net force perpendicular to the floor of the aircraft. This is because the aircraft generates appropriate lift and thrust to produce the desired vertical and longitudinal accelerations, respectively, although we measured moderate (0.2 g) aft-ward accelerations during certain parts of these trajectories. Aircraft pitch rotation (average 3°/s) is barely detectable by the vestibular system, but could influence some physics experiments. Investigators should consider such details in the planning, analysis, and interpretation of parabolic-flight experiments.

Ion Trap Quantum Computing

Science.gov (United States)

2011-12-01

variations of ion traps, including (1) the cylindrically symmetric 3D ring trap; (2) the linear trap with a combination of cavity QED; (#) the symmetric...concepts of quantum information. The major demonstration has been the test of a Bell inequality as demonstrated by Rowe et al. [50] and a decoherence...famous physics experiment [62]. Wolfgang Paul demonstrated a similar apparatus during his Nobel Prize speech [63]. This device is hyperbolic- parabolic

Soffer's inequality

International Nuclear Information System (INIS)

Goldstein, G.R.; Jaffe, R.L.; Ji, X.

1995-01-01

Various issues surrounding a recently proposed inequality among twist-two quark distributions in the nucleon are discussed. We provide a rigorous derivation of the inequality in QCD, including radiative corrections and scale dependence. We also give a more heuristic, but more physical derivation, from which we show that a similar inequality does not exist among twist-three quark distributions. We demonstrate that the inequality does not constrain the nucleon's tensor charge. Finally we explore physical mechanisms for saturating the inequality, arguing it is unlikely to occur in nature

Has the economic crisis widened the intraurban socioeconomic inequalities in mortality? The case of Barcelona, Spain.

Science.gov (United States)

Maynou, Laia; Saez, Marc; Lopez-Casasnovas, Guillem

2016-02-01

There is considerable evidence demonstrating socioeconomic inequalities in mortality, some of which focuses on intraurban inequalities. However, all the studies assume that the spatial variation of inequalities is stable over the time. We challenge this assumption and propose two hypotheses: (i) have spatial variations in socioeconomic inequalities in mortality at an intraurban level changed over time? and (ii) as a result of the economic crisis, has the gap between such disparities widened? In this paper, our objective is to assess the effect of the economic recession on the spatio-temporal variation of socioeconomic inequalities in mortality in Barcelona (Catalonia, Spain). We used a spatio-temporal ecological design to analyse mortality inequalities at small area level in Barcelona. Mortality data and socioeconomic indicators correspond to the years 2005 and 2008-2011. We specified spatio-temporal ecological mixed regressions for both men and women using two indicators, neighbourhood and year. We allowed the coefficients of the socioeconomic variables to differ according to the levels and explicitly took into account spatio-temporal adjustment. For men and women both absolute and, above all, relative risks for mortality have increased since 2009. In relative terms, this means that the risk of dying has increased much more in the most economically deprived neighbourhoods than in the more affluent ones. Although the geographical pattern in relative risks for mortality in neighbourhoods in Barcelona remained very stable between 2005 and 2011, socioeconomic inequalities in mortality at an intraurban level have surged since 2009. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

No association between gender inequality and peak HIV prevalence in developing countries - an ecological study.

Science.gov (United States)

Kenyon, Chris R; Buyze, Jozefien

2015-01-01

The prevalence of both gender inequality and HIV prevalence vary considerably both within all developing countries and within those in sub-Saharan Africa. We test the hypothesis that the extent of gender inequality is associated with national peak HIV prevalence. Linear regression was used to test the association between national peak HIV prevalence and three markers of gender equality - the gender-related development index (GDI), the gender empowerment measure (GEM), and the gender inequality index (GII). No evidence was found of a positive relationship between gender inequality and HIV prevalence, either in the analyses of all developing countries or those limited to Africa. In the bivariate analyses limited to Africa, there was a positive association between the two measures of gender "equality" and peak HIV prevalence (GDI: coefficient 28, 95% confidence interval (CI) 9.1-46.8; GEM: coefficient 54.8, 95% CI 20.5-89.1). There was also a negative association between the marker of gender "inequality" and peak HIV prevalence (GII: coefficient -66.9, 95% CI -112.8 to -21.0). These associations all disappeared on multivariate analyses. We could not find any evidence to support the hypothesis that variations in the extent of gender inequality explain variations in HIV prevalence in developing countries.

Wage Inequality and Return to Education in Indonesia: Quantile Regression Analysis

Directory of Open Access Journals (Sweden)

Restuning Dyah Widyanti

2018-01-01

Full Text Available It is essential to the government to recognize the factors causing the increasing trend of income inequality in Indonesia since the Gini coefficient increased between 1996 and 2016. Moreover, wage inequality, which represented by high percentile and low percentile of income, also shows widening gap since 2003. This study focuses on the factors of wage inequality acceleration through the supply side approach that follows the Mincerian wage equation model. Specifically, this paper aims to investigate the association between the return to education and wage inequality in Indonesia. The quantile regression method is applied to compute the return on the investment at different points of the wage distribution. The main finding is that education contributes to an increasing wage inequality due to the significant variation in the rate of return to education in different quantile and as increasing wage dispersion within the same education.DOI: 10.15408/sjie.v7i1.6071

A note on Hermitian-Einstein metrics on parabolic stable bundles

International Nuclear Information System (INIS)

Li Jiayu; Narasimhan, M.S.

2000-01-01

Let M-bar be a compact complex manifold of complex dimension two with a smooth Kaehler metric and D a smooth divisor on M-bar. If E is a rank 2 holomorphic vector bundle on M-bar with a stable parabolic structure along D, we prove that there exists a Hermitian-Einstein metric on E' = E-vertical bar M-barbackslashD compatible with the parabolic structure, and whose curvature is square integrable. (author)

Critical spaces for quasilinear parabolic evolution equations and applications

Science.gov (United States)

Prüss, Jan; Simonett, Gieri; Wilke, Mathias

2018-02-01

We present a comprehensive theory of critical spaces for the broad class of quasilinear parabolic evolution equations. The approach is based on maximal Lp-regularity in time-weighted function spaces. It is shown that our notion of critical spaces coincides with the concept of scaling invariant spaces in case that the underlying partial differential equation enjoys a scaling invariance. Applications to the vorticity equations for the Navier-Stokes problem, convection-diffusion equations, the Nernst-Planck-Poisson equations in electro-chemistry, chemotaxis equations, the MHD equations, and some other well-known parabolic equations are given.

Optimization method for an evolutional type inverse heat conduction problem

Science.gov (United States)

Deng, Zui-Cha; Yu, Jian-Ning; Yang, Liu

2008-01-01

This paper deals with the determination of a pair (q, u) in the heat conduction equation u_t-u_{xx}+q(x,t)u=0, with initial and boundary conditions u(x,0)=u_0(x),\\qquad u_x|_{x=0}=u_x|_{x=1}=0, from the overspecified data u(x, t) = g(x, t). By the time semi-discrete scheme, the problem is transformed into a sequence of inverse problems in which the unknown coefficients are purely space dependent. Based on the optimal control framework, the existence, uniqueness and stability of the solution (q, u) are proved. A necessary condition which is a couple system of a parabolic equation and parabolic variational inequality is deduced.

INERTIAL MANIFOLDS FOR NONAUTONOMOUS SEMILINEAR PARABOLIC PARTIAL DIFFERENTIAL EQUATIONS WITH TIME DELAYS

Institute of Scientific and Technical Information of China (English)

无

2006-01-01

The present paper deals with the long-time behavior of a class of nonautonomous retarded semilinear parabolic differential equations. When the time delays are small enough and the spectral gap conditions hold, the inertial manifolds of the nonautonomous retard parabolic equations are constructed by using the Lyapunov-Perron method.

Inequality

DEFF Research Database (Denmark)

Addison, Tony; Pirttilä, Jukka; Tarp, Finn

2017-01-01

Many low‐ and middle‐income countries are achieving good rates of economic growth, while high inequality remains a priority concern. Some countries meanwhile have low growth, high inequality, and pervasive poverty—often linked to their fragility. There is now active debate on how countries should...... set themselves goals for achieving both absolute poverty reduction and lower inequality. But policy action needs to be better served by analysis and data....

Convergence of shock waves between conical and parabolic boundaries

Energy Technology Data Exchange (ETDEWEB)

Yanuka, D.; Zinowits, H. E.; Antonov, O.; Efimov, S.; Virozub, A.; Krasik, Ya. E. [Physics Department, Technion, Haifa 32000 (Israel)

2016-07-15

Convergence of shock waves, generated by underwater electrical explosions of cylindrical wire arrays, between either parabolic or conical bounding walls is investigated. A high-current pulse with a peak of ∼550 kA and rise time of ∼300 ns was applied for the wire array explosion. Strong self-emission from an optical fiber placed at the origin of the implosion was used for estimating the time of flight of the shock wave. 2D hydrodynamic simulations coupled with the equations of state of water and copper showed that the pressure obtained in the vicinity of the implosion is ∼7 times higher in the case of parabolic walls. However, comparison with a spherical wire array explosion showed that the pressure in the implosion vicinity in that case is higher than the pressure in the current experiment with parabolic bounding walls because of strong shock wave reflections from the walls. It is shown that this drawback of the bounding walls can be significantly minimized by optimization of the wire array geometry.

Is the relative increase in income inequality related to tooth loss in middle-aged adults?

Science.gov (United States)

Goulart, Mariél de Aquino; Vettore, Mario Vianna

2016-01-01

To assess whether Brazilian middle-aged adults living in cities that experienced a relative increase on income inequality were more likely to have severe tooth loss and lack a functional dentition. Data on Brazilian adults aged 35-44 years from state capitals and Federal District from the 2010 Brazilian Oral Health Survey (SBBrasil 2010) were analyzed. Clinically assessed tooth loss outcomes were severe tooth loss (Income inequality was assessed by Gini Index in 1991, 2000, and 2003 using tertiles of distribution. Variation in Gini Index was assessed by changes in the tertiles distribution between years. Multilevel logistic regression models were used to estimate odds ratios (ORs) and 95 percent confidence intervals (95 percent CI) between variation in income inequality and tooth loss outcomes adjusting for individual socio-demographic characteristics. Prevalence of severe tooth loss and lack of functional dentition was 4.8 percent and 21.2 percent, respectively. Individuals living in cities with moderate and high increase in income inequality between 1991 and 2003 were more likely to have severe tooth loss and lack a functional dentition in 2010 compared with those living in cities with stable income inequality in the same period. Relationships between low family income and both tooth loss outcomes were significantly attenuated by relative increases in income inequality. Relative increases in income inequality were significantly associated with severe tooth loss and lack of a functional dentition in Brazilian middle-aged adults. © 2015 American Association of Public Health Dentistry.

Integrated parabolic nanolenses on MicroLED color pixels

Science.gov (United States)

Demory, Brandon; Chung, Kunook; Katcher, Adam; Sui, Jingyang; Deng, Hui; Ku, Pei-Cheng

2018-04-01

A parabolic nanolens array coupled to the emission of a nanopillar micro-light emitting diode (LED) color pixel is shown to reduce the far field divergence. For a blue wavelength LED, the total emission is 95% collimated within a 0.5 numerical aperture zone, a 3.5x improvement over the same LED without a lens structure. This corresponds to a half-width at half-maximum (HWHM) line width reduction of 2.85 times. Using a resist reflow and etchback procedure, the nanolens array dimensions and parabolic shape are formed. Experimental measurement of the far field emission shows a HWHM linewidth reduction by a factor of 2x, reducing the divergence over the original LED.

Nations’ Income Inequality Predicts Ambivalence in Stereotype Content: How Societies Mind the Gap

Science.gov (United States)

Durante, Federica; Fiske, Susan T.; Kervyn, Nicolas; Cuddy, Amy J. C.; Akande, Adebowale (Debo); Adetoun, Bolanle E.; Adewuyi, Modupe F.; Tserere, Magdeline M.; Ramiah, Ananthi Al; Mastor, Khairul Anwar; Barlow, Fiona Kate; Bonn, Gregory; Tafarodi, Romin W.; Bosak, Janine; Cairns, Ed; Doherty, Claire; Capozza, Dora; Chandran, Anjana; Chryssochoou, Xenia; Iatridis, Tilemachos; Contreras, Juan Manuel; Costa-Lopes, Rui; González, Roberto; Lewis, Janet I.; Tushabe, Gerald; Leyens, Jacques-Philippe; Mayorga, Renée; Rouhana, Nadim N.; Castro, Vanessa Smith; Perez, Rolando; Rodríguez-Bailón, Rosa; Moya, Miguel; Morales Marente, Elena; Palacios Gálvez, Marisol; Sibley, Chris G.; Asbrock, Frank; Storari, Chiara C.

2013-01-01

Income inequality undermines societies: the more inequality, the more health problems, social tensions, and the lower social mobility, trust, life expectancy. Given people’s tendency to legitimate existing social arrangements, the Stereotype Content Model (SCM) argues that ambivalence—perceiving many groups as either warm or competent, but not both—may help maintain socio-economic disparities. The association between stereotype ambivalence and income inequality in 37 cross-national samples from Europe, the Americas, Oceania, Asia, and Africa investigates how groups’ overall warmth-competence, status-competence, and competition-warmth correlations vary across societies, and whether these variations associate with income inequality (Gini index). More unequal societies report more ambivalent stereotypes, while more equal ones dislike competitive groups and do not necessarily respect them as competent. Unequal societies may need ambivalence for system stability: income inequality compensates groups with partially positive social images. PMID:23039178

Improvement of Aczél's Inequality and Popoviciu's Inequality

Directory of Open Access Journals (Sweden)

Shanhe Wu

2007-06-01

Full Text Available We generalize and sharpen Aczél's inequality and Popoviciu's inequality by means of two classical inequalities, a unified improvement of Aczél's inequality and Popoviciu's inequality is given. As application, an integral inequality of Aczél-Popoviciu type is established.

Nonlinear anisotropic parabolic equations in Lm

Directory of Open Access Journals (Sweden)

Fares Mokhtari

2014-01-01

Full Text Available In this paper, we give a result of regularity of weak solutions for a class of nonlinear anisotropic parabolic equations with lower-order term when the right-hand side is an Lm function, with m being ”small”. This work generalizes some results given in [2] and [3].

Global Carleman estimates for degenerate parabolic operators with applications

CERN Document Server

Cannarsa, P; Vancostenoble, J

2016-01-01

Degenerate parabolic operators have received increasing attention in recent years because they are associated with both important theoretical analysis, such as stochastic diffusion processes, and interesting applications to engineering, physics, biology, and economics. This manuscript has been conceived to introduce the reader to global Carleman estimates for a class of parabolic operators which may degenerate at the boundary of the space domain, in the normal direction to the boundary. Such a kind of degeneracy is relevant to study the invariance of a domain with respect to a given stochastic diffusion flow, and appears naturally in climatology models.

Socio-economic inequality in multiple health complaints among adolescents: international comparative study in 37 countries

DEFF Research Database (Denmark)

Holstein, Bjørn E; Currie, Candace; Boyce, Will

2009-01-01

OBJECTIVES: To use comparable data from many countries to examine 1) socio-economic inequality in multiple health complaints among adolescents, 2) whether the countries' absolute wealth and economic inequality was associated with symptom load among adolescents, and 3) whether the countries......' absolute wealth and economic inequality explained part of the individual level socio-economic variation in health complaints. METHODS: The Health Behaviour in School-aged Children (HBSC) international study from 2005/06 provided data on 204,534 11-, 13- and 15-year old students from nationally random...... Affluence Scale FAS) and two macro level measures on the country's economic situation: wealth measured by Gross National Product (GNP) and distribution of income measured by the Gini coefficient. RESULTS: There was a significant socio-economic variation in health complaints in 31 of the 37 countries...

Nordic paradox, Southern miracle, Eastern disaster: persistence of inequalities in mortality in Europe.

Science.gov (United States)

Mackenbach, Johan P

2017-10-01

The persistence of socioeconomic inequalities in health, despite all that has been done to reduce social and economic inequalities in many European countries, is one of the great disappointments of public health. In this paper, I summarize the results of a series of studies into the explanation of variations and trends in inequalities in mortality in three European regions: the Nordic countries with their puzzlingly large inequalities in mortality, Southern European countries with their miraculously small inequalities in mortality and Central & Eastern European countries in which inequalities in mortality have disastrously exploded since the early 1990 s. The results of these studies show that inequalities in mortality are remarkably variable and dynamic, which suggests that it may be possible to reduce them if we exploit the entry-points for policy that these studies have also identified, such as poverty, smoking, excessive alcohol consumption and lack of access to health care. At the same time, another lesson is that health inequalities are influenced in sometimes unexpected ways by factors that are not under our control, and that we cannot expect to eliminate these health inequalities soon. © The Author 2017. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

Numerical performance of the parabolized ADM formulation of general relativity

International Nuclear Information System (INIS)

Paschalidis, Vasileios; Hansen, Jakob; Khokhlov, Alexei

2008-01-01

In a recent paper [Vasileios Paschalidis, Phys. Rev. D 78, 024002 (2008).], the first coauthor presented a new parabolic extension (PADM) of the standard 3+1 Arnowitt, Deser, Misner (ADM) formulation of the equations of general relativity. By parabolizing first-order ADM in a certain way, the PADM formulation turns it into a well-posed system which resembles the structure of mixed hyperbolic-second-order parabolic partial differential equations. The surface of constraints of PADM becomes a local attractor for all solutions and all possible well-posed gauge conditions. This paper describes a numerical implementation of PADM and studies its accuracy and stability in a series of standard numerical tests. Numerical properties of PADM are compared with those of standard ADM and its hyperbolic Kidder, Scheel, Teukolsky (KST) extension. The PADM scheme is numerically stable, convergent, and second-order accurate. The new formulation has better control of the constraint-violating modes than ADM and KST.

First Middle East Aircraft Parabolic Flights for ISU Participant Experiments

Science.gov (United States)

Pletser, Vladimir; Frischauf, Norbert; Cohen, Dan; Foster, Matthew; Spannagel, Ruven; Szeszko, Adam; Laufer, Rene

2017-06-01

Aircraft parabolic flights are widely used throughout the world to create microgravity environment for scientific and technology research, experiment rehearsal for space missions, and for astronaut training before space flights. As part of the Space Studies Program 2016 of the International Space University summer session at the Technion - Israel Institute of Technology, Haifa, Israel, a series of aircraft parabolic flights were organized with a glider in support of departmental activities on `Artificial and Micro-gravity' within the Space Sciences Department. Five flights were organized with manoeuvres including several parabolas with 5 to 6 s of weightlessness, bank turns with acceleration up to 2 g and disorientation inducing manoeuvres. Four demonstration experiments and two experiments proposed by SSP16 participants were performed during the flights by on board operators. This paper reports on the microgravity experiments conducted during these parabolic flights, the first conducted in the Middle East for science and pedagogical experiments.

Gender inequalities in mental wellbeing in 26 European countries: do welfare regimes matter?

Science.gov (United States)

Dreger, Stefanie; Gerlinger, Thomas; Bolte, Gabriele

2016-10-01

Nature and extent of welfare regimes and social policies are important determinants of health and health inequalities. This study examines the association of gender and mental wellbeing in European countries and investigates whether type of welfare regime plays a role in this association. Data of 19 366 women and 14 338 men of the third round of the European Quality of Life Survey (2011-12) was used to analyse mental wellbeing, assessed by the World Health Organization 5-Mental Wellbeing Index. Multilevel logistic regression analyses were performed to analyse the association between gender and good mental wellbeing first at country-level, and secondly the between country variation was analysed and welfare regimes were included as explanatory variables. We observed cross-national variation in good mental wellbeing. At country levels gender inequalities in good mental wellbeing were observed in 7 out of 26 countries. In analyses considering all countries together gender inequalities in good mental wellbeing were identified independent of further individual socio-demographic variables and independent of the welfare regimes that people lived in [women vs. men: OR = 0.76; (95% CI = 0.71-0.81)]. Gender inequalities in good mental wellbeing were not modified by welfare regimes. There are cross-national differences in good mental wellbeing between European countries. Gender inequalities with a lower prevalence of good mental wellbeing among women are common in European countries. This study suggests that welfare regimes do not modify these gender inequalities in mental wellbeing. © The Author 2016. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

Patterned Inequalities and the Inequality Regime of a Swedish Housing Company

Directory of Open Access Journals (Sweden)

Kristina Boréus

2015-12-01

Full Text Available In this article, the authors analyze inequalities between different groups of employees at a housing company in a larger Swedish city. The concept of inequality regime is taken as a point of departure. The purposes of the article are three: first, to add to knowledge of how inequality is generated at an organizational level at specific workplaces; second, to contribute to the understanding of how different practices, processes, and meanings of inequality regimes may interact to create and reinforce inequalities between natives and immigrants; and, third, to contribute to the empirical usefulness of the concept of inequality regime by demonstrating how it can be operationalized and combined with other concepts in the analysis. The study shows how the practices, processes, and meanings at the given workplace generated and reproduced different kinds of inequalities: unequal wages, an ethnic division of labor, unequal influence and job security, and unequal opportunities to capitalize on useful skills (i.e., language competence. Important conclusions are that different kinds of inequalities may reinforce each other by creating vicious circles, and subtler forms of inequality may partly explain explicit wage inequalities.

Iterative Methods for Solving Nonlinear Parabolic Problem in Pension Saving Management

Science.gov (United States)

Koleva, M. N.

2011-11-01

In this work we consider a nonlinear parabolic equation, obtained from Riccati like transformation of the Hamilton-Jacobi-Bellman equation, arising in pension saving management. We discuss two numerical iterative methods for solving the model problem—fully implicit Picard method and mixed Picard-Newton method, which preserves the parabolic characteristics of the differential problem. Numerical experiments for comparison the accuracy and effectiveness of the algorithms are discussed. Finally, observations are given.

Trajectory Optimization for Spacecraft Collision Avoidance

Science.gov (United States)

2013-09-01

Parabolic e > 1 Hyperbolic The RAAN, Ω, measures the angle between the vernal equinox eastward to the line of nodes, n, shown in Figure 3 and...Methods. Indirect Methods focus on derivation of first-order necessary conditions using the Calculus of Variations . These conditions are then used to...either the final or initial states. They may be given as a set of equality or inequality constraints. A state vector that does not violate any

Cost-effective solar furnace system using fixed geometry Non-Imaging Focusing Heliostat and secondary parabolic concentrator

Energy Technology Data Exchange (ETDEWEB)

Chong, K.K.; Lim, C.Y.; Hiew, C.W. [Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Off Jalan Genting Kelang, Setapak, Kuala Lumpur 53300 (Malaysia)

2011-05-15

A novel cost-effective solar furnace system is proposed to be consisted of a Non-Imaging Focusing Heliostat (NIFH) and a much smaller parabolic concentrator. In order to simplify the design and hence leading to the cost reduction, a fixed geometry of the NIFH heliostat is adopted in the novel solar furnace system by omitting the requirement of continuous astigmatic correction throughout the year with the use of local controllers. The performance of this novel solar furnace configuration can be optimized when the heliostat's spinning-axis is orientated in such a way that the annual variations of incident angle and therefore the annual variations of aberrant image size are the least. To verify the new configuration, a prototype solar furnace has been constructed at Universiti Tunku Abdul Rahman. (author)

Institutional Framework of Income Inequality in Modern Economy

Directory of Open Access Journals (Sweden)

Malkina Marina, Yu.

2016-03-01

Full Text Available The subject of this paper is interpersonal income inequality in Russia and in the world and its institutional framework. On the basis of in-depth analysis of the literature we explore the causes and consequences of inequality and its relationship with economic development. We distinguish four basic causes of income inequality: natural and acquired features of people; status differences and their limitations; differences in productivity and development peculiarities in various industries; uneven distribution of accumulated property, as well as the return on assets in dynamics and assets assessment characteristics. By means of the calculation of a number of generalizing measures (coefficient of variation, Gini, Hoover, Theil, Theil-Bernoulli and Atkinson indexes for the Russian economy we revealed a positive relationship between the average level of wages in industries and its intra-differentiation, which is more typical for the private sector of the economy. At the same time it has been found convergence in salaries differentiation in the public sector of the Russian economy to salaries differentiation in the private sector, while there is not confirmed any correlation between wage level and intra-wage differences in the public sector industries. It enabled us to conclude about the deterioration of the institutional environment in the public sector. In the second part of our paper we compared two approaches to the role of institutional environment in inequality: the approach of T. Piketty (according to which rising inequality is the result of market laws and market institutions in general, and the approach of D. Acemoglu and others (inequality is due to the bad quality of institutions, which is formed largely endogenously in a particular environment. Bending over to the second point of view, we analyzed the relationship between inequality and interdependence of political and economic institutions. In particular, we examined the impact of the

Digit ratio (2D:4D) and gender inequalities across nations

OpenAIRE

Manning, John; Fink, Bernhard; Trivers, Robert

2014-01-01

Gender inequality varies across nations, where such inequality is defined as the disproportionate representation of one sex over the other in desirable social, economic, and biological roles (typically male over female). Thus in Norway, 40% of parliamentarians are women, in the USA 17%, and in Saudi Arabia 0%. Some of this variation is associated with economic prosperity but there is evidence that this cause and effect can go in either direction. Here we show that within a population the aver...

Spike-adding in parabolic bursters: The role of folded-saddle canards

Science.gov (United States)

Desroches, Mathieu; Krupa, Martin; Rodrigues, Serafim

2016-09-01

The present work develops a new approach to studying parabolic bursting, and also proposes a novel four-dimensional canonical and polynomial-based parabolic burster. In addition to this new polynomial system, we also consider the conductance-based model of the Aplysia R15 neuron known as the Plant model, and a reduction of this prototypical biophysical parabolic burster to three variables, including one phase variable, namely the Baer-Rinzel-Carillo (BRC) phase model. Revisiting these models from the perspective of slow-fast dynamics reveals that the number of spikes per burst may vary upon parameter changes, however the spike-adding process occurs in an explosive fashion that involves special solutions called canards. This spike-adding canard explosion phenomenon is analysed by using tools from geometric singular perturbation theory in tandem with numerical bifurcation techniques. We find that the bifurcation structure persists across all considered systems, that is, spikes within the burst are incremented via the crossing of an excitability threshold given by a particular type of canard orbit, namely the true canard of a folded-saddle singularity. However there can be a difference in the spike-adding transitions in parameter space from one case to another, according to whether the process is continuous or discontinuous, which depends upon the geometry of the folded-saddle canard. Using these findings, we construct a new polynomial approximation of the Plant model, which retains all the key elements for parabolic bursting, including the spike-adding transitions mediated by folded-saddle canards. Finally, we briefly investigate the presence of spike-adding via canards in planar phase models of parabolic bursting, namely the theta model by Ermentrout and Kopell.

Degenerate parabolic stochastic partial differential equations

Czech Academy of Sciences Publication Activity Database

span class="emphasis">Hofmanová, Martinaspan>

2013-01-01

Roč. 123, č. 12 (2013), s. 4294-4336 ISSN 0304-4149 R&D Projects: GA ČR GAP201/10/0752 Institutional support: RVO:67985556 Keywords : kinetic solutions * degenerate stochastic parabolic equations Subject RIV: BA - General Mathematics Impact factor: 1.046, year: 2013 http://library.utia.cas.cz/separaty/2013/SI/hofmanova-0397241.pdf

A relevant two qubit Bell inequality inequivalent to the CHSH inequality

International Nuclear Information System (INIS)

Collins, Daniel; Gisin, Nicolas

2004-01-01

We computationally investigate the complete polytope of Bell inequalities for two particles with small numbers of possible measurements and outcomes. Our approach is limited by Pitowsky's connection of this problem to the computationally hard NP problem. Despite this, we find that there are very few relevant inequivalent inequalities for small numbers. For example, in the case with three possible 2-outcome measurements on each particle, there is just one new inequality. We describe mixed 2-qubit states which violate this inequality but not the CHSH. The new inequality also illustrates a sharing of bi-partite non-locality between three qubits: something not seen using the CHSH inequality. It also inspires us to discover a class of Bell inequalities with m possible n-outcome measurements on each particle

A parabolic mirror x-ray collimator

Science.gov (United States)

Franks, A.; Jackson, K.; Yacoot, A.

2000-05-01

A robust and stable x-ray collimator has been developed to produce a parallel beam of x-rays by total external reflection from a parabolic mirror. The width of the gold-coated silica mirror varies along its length, which allows it to be bent from a plane surface into a parabolic form by application of unequal bending forces at its ends. A family of parabolas of near constant focal length can be formed by changing the screw-applied bending force, thus allowing the collimator to cater for a range of wavelengths by the turning of a screw. Even with radiation with a wavelength as short as that as Mo Kicons/Journals/Common/alpha" ALT="alpha" ALIGN="TOP"/> 1 (icons/Journals/Common/lambda" ALT="lambda" ALIGN="TOP"/> = 0.07 nm), a gain in flux by a factor of 5.5 was achieved. The potential gain increases with wavelength, e.g. for Cu Kicons/Journals/Common/alpha" ALT="alpha" ALIGN="TOP"/> 1 radiation this amounts to over a factor of ten.

Inequalities in the distribution of pharmacists' wage-and-salary earnings: indicators and their development.

Science.gov (United States)

Carvajal, Manuel J; Armayor, Graciela M

2013-01-01

Disparities in wages and salaries can be viewed as the dispersion of a statistical distribution that responds to observed and unobserved characteristics, and reflects socioeconomic phenomena such as the interplay of supply and demand, availability of information, and efficiency of markets in their search for equilibrium. The aim of this study was to explore the nature of inequality in the distribution of pharmacists' wage-and-salary earnings and establish the extent to which inequality primarily occurred because of variation between/among groups or within groups of pharmacists in several classifications of human-capital and job-related preference variables. Data were collected through the use of a survey questionnaire mailed to registered pharmacists in South Florida, USA. Five indicators of inequality (the log earnings variance, the coefficient of variation, the lower median share, the 90-10 decile ratio, and the Gini coefficient) were estimated for eight human-capital classifications and eight job-related classifications. A one-way ANOVA model was applied to the groups in each classification to compare variation between/among versus within pharmacy groups. Pharmacists' wage-and-salary earnings were more evenly distributed than most income distributions discussed in the literature. They were more equitably distributed for full-time pharmacists than for all pharmacists in the data set. All five-inequality indicators behaved similarly. Notable differences were observed between/among groups within the gender, age group, marital status, number of children, academic degree, and type of primary pharmacy activity classifications. Inequalities in wages and salaries have been identified both between/among and within pharmacist groups in several classifications using five commonly accepted indicators. Copyright © 2013 Elsevier Inc. All rights reserved.

Moving interfaces and quasilinear parabolic evolution equations

CERN Document Server

Prüss, Jan

2016-01-01

In this monograph, the authors develop a comprehensive approach for the mathematical analysis of a wide array of problems involving moving interfaces. It includes an in-depth study of abstract quasilinear parabolic evolution equations, elliptic and parabolic boundary value problems, transmission problems, one- and two-phase Stokes problems, and the equations of incompressible viscous one- and two-phase fluid flows. The theory of maximal regularity, an essential element, is also fully developed. The authors present a modern approach based on powerful tools in classical analysis, functional analysis, and vector-valued harmonic analysis. The theory is applied to problems in two-phase fluid dynamics and phase transitions, one-phase generalized Newtonian fluids, nematic liquid crystal flows, Maxwell-Stefan diffusion, and a variety of geometric evolution equations. The book also includes a discussion of the underlying physical and thermodynamic principles governing the equations of fluid flows and phase transitions...

Fighting status inequalities

DEFF Research Database (Denmark)

Nielsen, Morten Ebbe Juul; Landes, Xavier

2016-01-01

Status inequalities seem to play a fairly big role in creating inequalities in health. This article assumes that there can be good reasons to fight status inequalities in order to reduce inequalities in health. It examines whether the neorepublican ideal of non-dominance does a better job as a th...

Wind load design methods for ground-based heliostats and parabolic dish collectors

Energy Technology Data Exchange (ETDEWEB)

Peterka, J A; Derickson, R G [Colorado State Univ., Fort Collins, CO (United States). Fluid Dynamics and Diffusion Lab.

1992-09-01

The purpose of this design method is to define wind loads on flat heliostat and parabolic dish collectors in a simplified form. Wind loads are defined for both mean and peak loads accounting for the protective influence of upwind collectors, wind protective fences, or other wind-blockage elements. The method used to define wind loads was to generalize wind load data obtained during tests on model collectors, heliostats or parabolic dishes, placed in a modeled atmospheric wind in a boundary-layer wind-tunnel at Colorado State University. For both heliostats and parabolic dishes, loads are reported for solitary collectors and for collectors as elements of a field. All collectors were solid with negligible porosity; thus the effects of porosity in the collectors is not addressed.

Accelerated Simulation of Kinetic Transport Using Variational Principles and Sparsity

Energy Technology Data Exchange (ETDEWEB)

Caflisch, Russel [Univ. of California, Los Angeles, CA (United States)

2017-06-30

This project is centered on the development and application of techniques of sparsity and compressed sensing for variational principles, PDEs and physics problems, in particular for kinetic transport. This included derivation of sparse modes for elliptic and parabolic problems coming from variational principles. The research results of this project are on methods for sparsity in differential equations and their applications and on application of sparsity ideas to kinetic transport of plasmas.

Gas Turbine/Solar Parabolic Trough Hybrid Designs: Preprint

Energy Technology Data Exchange (ETDEWEB)

Turchi, C. S.; Ma, Z.; Erbes, M.

2011-03-01

A strength of parabolic trough concentrating solar power (CSP) plants is the ability to provide reliable power by incorporating either thermal energy storage or backup heat from fossil fuels. Yet these benefits have not been fully realized because thermal energy storage remains expensive at trough operating temperatures and gas usage in CSP plants is less efficient than in dedicated combined cycle plants. For example, while a modern combined cycle plant can achieve an overall efficiency in excess of 55%; auxiliary heaters in a parabolic trough plant convert gas to electricity at below 40%. Thus, one can argue the more effective use of natural gas is in a combined cycle plant, not as backup to a CSP plant. Integrated solar combined cycle (ISCC) systems avoid this pitfall by injecting solar steam into the fossil power cycle; however, these designs are limited to about 10% total solar enhancement. Without reliable, cost-effective energy storage or backup power, renewable sources will struggle to achieve a high penetration in the electric grid. This paper describes a novel gas turbine / parabolic trough hybrid design that combines solar contribution of 57% and higher with gas heat rates that rival that for combined cycle natural gas plants. The design integrates proven solar and fossil technologies, thereby offering high reliability and low financial risk while promoting deployment of solar thermal power.

The Relationship between Income Inequality and Inequality in Schooling

Science.gov (United States)

Mayer, Susan E.

2010-01-01

Children of affluent parents get more schooling than children of poor parents, which seems to imply that reducing income inequality would reduce inequality in schooling. Similarly, one of the best predictors of an individual's income is his educational attainment, which seems to imply that reducing inequality in schooling will reduce income…

Dynamic inequalities on time scales

CERN Document Server

Agarwal, Ravi; Saker, Samir

2014-01-01

This is a monograph devoted to recent research and results on dynamic inequalities on time scales. The study of dynamic inequalities on time scales has been covered extensively in the literature in recent years and has now become a major sub-field in pure and applied mathematics. In particular, this book will cover recent results on integral inequalities, including Young's inequality, Jensen's inequality, Holder's inequality, Minkowski's inequality, Steffensen's inequality, Hermite-Hadamard inequality and Čebyšv's inequality. Opial type inequalities on time scales and their extensions with weighted functions, Lyapunov type inequalities, Halanay type inequalities for dynamic equations on time scales, and Wirtinger type inequalities on time scales and their extensions will also be discussed here in detail.

Improvement Design of Parabolic Trough

Science.gov (United States)

Ihsan, S. I.; Safian, M. A. I. M.; Taufek, M. A. M.; Mohiuddin, A. K. M.

2017-03-01

The performance of parabolic trough solar collector (PTSC) has been evaluated using different heat transfer working fluids; namely water and SAE20 W50 engine oil. New and slightly improved PTSC was developed to run the experimental study. Under the meteorological conditions of Malaysia, authors found that PTSC can operate at a higher temperature than water collector but the performance efficiency of collector using engine oil is much lower than the water collector.

THE DAMASCUS INEQUALITY

Directory of Open Access Journals (Sweden)

F. M. Dannan

2016-12-01

Full Text Available In 2016 Prof. Fozi M. Dannan from Damascus, Syria, proposed an interesting inequality for three positive numbers with unit product. It became widely known but was not proved yet in spite of elementary formulation. In this paper we prove this inequality together with similar ones, its proof occurred to be rather complicated. We propose some proofs based on different ideas: Lagrange multipliers method, geometrical considerations, Klamkin–type inequalities for symmetric functions, usage of symmetric reduction functions of computer packages. Also some corollaries and generalizations are considered, they include cycle inequalities, triangle geometric inequalities, inequalities for arbitrary number of values and special forms of restrictions on numbers, applications to cubic equations and symmetric functions.

Educational inequalities in parental care time: Cross-national evidence from Belgium, Denmark, Spain, and the United Kingdom.

Science.gov (United States)

Gracia, Pablo; Ghysels, Joris

2017-03-01

This study uses time-diary data for dual-earner couples from Belgium, Denmark, Spain, and the United Kingdom to analyze educational inequalities in parental care time in different national contexts. For mothers, education is significantly associated with parenting involvement only in Spain and the United Kingdom. In Spain these differences are largely explained by inequalities in mothers' time and monetary resources, but not in the United Kingdom, where less-educated mothers disproportionally work in short part-time jobs. For fathers, education is associated with parenting time in Denmark, and particularly in Spain, while the wife's resources substantially drive these associations. On weekends, the educational gradient in parental care time applies only to Spain and the United Kingdom, two countries with particularly large inequalities in parents' opportunities to engage in parenting. The study shows country variations in educational inequalities in parenting, suggesting that socioeconomic resources, especially from mothers, shape important variations in parenting involvement. Copyright © 2016. Published by Elsevier Inc.

A gradient estimate for solutions to parabolic equations with discontinuous coefficients

Directory of Open Access Journals (Sweden)

Jishan Fan

2013-04-01

Full Text Available Li-Vogelius and Li-Nirenberg gave a gradient estimate for solutions of strongly elliptic equations and systems of divergence forms with piecewise smooth coefficients, respectively. The discontinuities of the coefficients are assumed to be given by manifolds of codimension 1, which we called them emph{manifolds of discontinuities}. Their gradient estimate is independent of the distances between manifolds of discontinuities. In this paper, we gave a parabolic version of their results. That is, we gave a gradient estimate for parabolic equations of divergence forms with piecewise smooth coefficients. The coefficients are assumed to be independent of time and their discontinuities are likewise the previous elliptic equations. As an application of this estimate, we also gave a pointwise gradient estimate for the fundamental solution of a parabolic operator with piecewise smooth coefficients. Both gradient estimates are independent of the distances between manifolds of discontinuities.

Performance of Infinitely Wide Parabolic and Inclined Slider Bearings Lubricated with Couple Stress or Magnetic Fluids

Science.gov (United States)

Oladeinde, Mobolaji Humphrey; Akpobi, John Ajokpaoghene

2011-10-01

The hydrodynamic and magnetohydrodynamic (MHD) lubrication problem of infinitely wide inclined and parabolic slider bearings is solved numerically using the finite element method. The bearing configurations are discretized into three-node isoparametric quadratic elements. Stiffness integrals obtained from the weak form of the governing equations are solved using Gauss quadrature to obtain a finite number of stiffness matrices. The global system of equations obtained from enforcing nodal continuity of pressure for the bearings are solved using the Gauss-Seidel iterative scheme with a convergence criterion of 10-10. Numerical computations reveal that, when compared for similar profile and couple stress parameters, greater pressure builds up in a parabolic slider compared to an inclined slider, indicating a greater wedge effect in the parabolic slider. The parabolic slider bearing is also shown to develop a greater load capacity when lubricated with magnetic fluids. The superior performance of parabolic slider bearing is more pronounced at greater Hartmann numbers for identical bearing structural parameters. It is also shown that when load carrying capacity is the yardstick for comparison, the parabolic slider bearings are superior to the inclined bearings when lubricated with couple stress or magnetic lubricants.

Optimization method for an evolutional type inverse heat conduction problem

International Nuclear Information System (INIS)

Deng Zuicha; Yu Jianning; Yang Liu

2008-01-01

This paper deals with the determination of a pair (q, u) in the heat conduction equation u t -u xx +q(x,t)u=0, with initial and boundary conditions u(x,0)=u 0 (x), u x vertical bar x=0 =u x vertical bar x=1 =0, from the overspecified data u(x, t) = g(x, t). By the time semi-discrete scheme, the problem is transformed into a sequence of inverse problems in which the unknown coefficients are purely space dependent. Based on the optimal control framework, the existence, uniqueness and stability of the solution (q, u) are proved. A necessary condition which is a couple system of a parabolic equation and parabolic variational inequality is deduced

A review of Andasol 3 and perspective for parabolic trough CSP plants in South Africa

Science.gov (United States)

Dinter, Frank; Möller, Lucas

2016-05-01

Andasol 3 is a 50 MW parabolic trough concentrating solar power plant with thermal energy storage in Andalusia, southern Spain. Having started operating in 2011 as one of the first plants of its kind in Spain it has been followed by more than 50 in the country since. For the reason that CSP plants with storage have the potential to compete against fossil fuel fired plants much better than any other renewable energy source a long-term review of such a plant operating on a commercial scale is needed. With data at hand documenting Andasol 3's operation over the course of one year between July 2013 and June 2014 we intend to provide such a review. We calculated the plants overall efficiency, its capacity factor, the gross energy generation as well as auxiliary powers on a monthly basis to reflect upon its overall performance. It was also looked at the benefits caused by the thermal energy storage and especially how steadily and reliably the plant was able to operate. With basic background information about physical, geographical and meteorological aspects influencing the solar resource, its variation and a CSP plant's performance a qualitative estimation for a parabolic trough plant located in South Africa was made.

Analysis of the stress-deformed condition of the disassembly parabolic antenna

Science.gov (United States)

Odinets, M. N.; Kaygorodtseva, N. V.; Krysova, I. V.

2018-01-01

Active development of satellite communications and computer-aided design systems raises the problem of designing parabolic antennas on a new round of development. The aim of the work was to investigate the influence of the design of the mirror of a parabolic antenna on its endurance under wind load. The research task was an automated analysis of the stress-deformed condition of various designs of computer models of a paraboloid mirror (segmented or holistic) at modeling the exploitation conditions. The peculiarity of the research was that the assembly model of the antenna’s mirror was subjected to rigid connections on the contacting surfaces of the segments and only then the finite element grid was generated. The analysis showed the advantage of the design of the demountable antenna, which consists of cyclic segments, in front of the construction of the holistic antenna. Calculation of the stress-deformed condition of the antennas allows us to conclude that dividing the design of the antenna’s mirror on parabolic and cyclic segments increases it strength and rigidity. In the future, this can be used to minimize the mass of antenna and the dimensions of the disassembled antenna. The presented way of modeling a mirror of a parabolic antenna using to the method of the finite-element analysis can be used in the production of antennas.

The Ginibre inequality

International Nuclear Information System (INIS)

Sylvester, G.S.

1980-01-01

In the Ising-type models of statistical mechanics and the related quantum field theories, an inequality of Ginibre implies useful positivity and monotonicity properties: the Griffiths correlation inequalities. Essentially, the Ginibre inequality states that certain functions on the cycle group of a graph are positive definite. This has been proved for arbitrary graphs when the spin dimensions is 1 or 2 (classical Ising or plane rotator models). We give a counterexample to show that these spin dimensions are the only ones for which the Ginibre inequality is generally true: there are graphs for which it never holds when the spin dimension is at least 3. On the other hand, we show that for any graph the inequality holds for the apparent leading term in the large-spin-dimension limit. (The leading term vanishes in the graph of the counterexample.) Based on these results, one expects the Ginibre inequality to be true in most instances, with infrequent exceptions. A numerical survey supports this. The surprising failure of the Ginibre inequality in higher dimensions need not necessarily mean the Griffiths inequalities fail as well, but a different approach to them is required. (orig.)

Some blow-up problems for a semilinear parabolic equation with a potential

Science.gov (United States)

Cheng, Ting; Zheng, Gao-Feng

The blow-up rate estimate for the solution to a semilinear parabolic equation u=Δu+V(x)|u in Ω×(0,T) with 0-Dirichlet boundary condition is obtained. As an application, it is shown that the asymptotic behavior of blow-up time and blow-up set of the problem with nonnegative initial data u(x,0)=Mφ(x) as M goes to infinity, which have been found in [C. Cortazar, M. Elgueta, J.D. Rossi, The blow-up problem for a semilinear parabolic equation with a potential, preprint, arXiv: math.AP/0607055, July 2006], is improved under some reasonable and weaker conditions compared with [C. Cortazar, M. Elgueta, J.D. Rossi, The blow-up problem for a semilinear parabolic equation with a potential, preprint, arXiv: math.AP/0607055, July 2006].

Polarization properties of linearly polarized parabolic scaling Bessel beams

Energy Technology Data Exchange (ETDEWEB)

Guo, Mengwen; Zhao, Daomu, E-mail: zhaodaomu@yahoo.com

2016-10-07

The intensity profiles for the dominant polarization, cross polarization, and longitudinal components of modified parabolic scaling Bessel beams with linear polarization are investigated theoretically. The transverse intensity distributions of the three electric components are intimately connected to the topological charge. In particular, the intensity patterns of the cross polarization and longitudinal components near the apodization plane reflect the sign of the topological charge. - Highlights: • We investigated the polarization properties of modified parabolic scaling Bessel beams with linear polarization. • We studied the evolution of transverse intensity profiles for the three components of these beams. • The intensity patterns of the cross polarization and longitudinal components can reflect the sign of the topological charge.

Modelling the effect of size-asymmetric competition on size inequality

DEFF Research Database (Denmark)

Rasmussen, Camilla Ruø; Weiner, Jacob

2017-01-01

Abstract The concept of size asymmetry in resource competition among plants, in which larger individuals obtain a disproportionate share of contested resources, appears to be very straightforward, but the effects of size asymmetry on growth and size variation among individuals have proved...... to be controversial. It has often been assumed that competition among individual plants in a population has to be size-asymmetric to result in higher size inequality than in the absence of competition, but here we question this inference. Using very simple, individual-based models, we investigate how size symmetry...... of competition affects the development in size inequality between two competing plants and show that increased size inequality due to competition is not always strong evidence for size-asymmetric competition. Even absolute symmetric competition, in which all plants receive the same amount of resources...

High-Accuracy Near-Surface Large-Eddy Simulation with Planar Topography

Science.gov (United States)

2015-08-03

parabolic profile characteristic of laminar Newtonian channel flow. Thus, although the LES equation contains no true frictional term, the numerical LES...least five times than the spurious viscous length scale. The inequality (30) is satisfied when * , so that the first and second criteria are met...lines of constant slope 2 1 / N  . However the variation in 1 is not so great as to obscure the strong inverse relationship between the slopes

Is the social volcano still dormant? Trends in Chinese attitudes toward inequality.

Science.gov (United States)

Whyte, Martin King; Im, Dong-Kyun

2014-11-01

Data from two China national surveys, in 2004 and 2009, focusing on popular attitudes toward current inequalities and mobility opportunities, are compared to examine two key questions: (1) Did the continued rise in income gaps and the impact within China of the global financial crisis lead to rising popular anger about the unfairness of current inequality patterns in 2009? and (2) Did the social contours of attitudes toward current inequalities shift over the five years between surveys? Through systematic comparisons of data from both surveys, we conclude that there is no general increase in anger about inequalities in the 2009 survey, and that the predictors of variations in these attitudes had changed relatively little, with the unexpectedly positive views of villagers still visible in 2009, although a bit muted. Trends in Chinese society between 2004 and 2009, and in the personal experience of survey respondents, are used to explain why popular acceptance of current inequalities remains widespread, despite continuing increases in China's income gaps. Copyright © 2014 Elsevier Inc. All rights reserved.

Quasivariational Solutions for First Order Quasilinear Equations with Gradient Constraint

Science.gov (United States)

Rodrigues, José Francisco; Santos, Lisa

2012-08-01

We prove the existence of solutions for a quasi-variational inequality of evolution with a first order quasilinear operator and a variable convex set which is characterized by a constraint on the absolute value of the gradient that depends on the solution itself. The only required assumption on the nonlinearity of this constraint is its continuity and positivity. The method relies on an appropriate parabolic regularization and suitable a priori estimates. We also obtain the existence of stationary solutions by studying the asymptotic behaviour in time. In the variational case, corresponding to a constraint independent of the solution, we also give uniqueness results.

Chernoff's distribution and parabolic partial differential equations

NARCIS (Netherlands)

P. Groeneboom; S.P. Lalley; N.M. Temme (Nico)

2013-01-01

textabstractWe give an alternative route to the derivation of the distribution of the maximum and the location of the maximum of one-sided and two-sided Brownian motion with a negative parabolic drift, using the Feynman-Kac formula with stopping times. The derivation also uses an interesting

Anthropometric Evidence of Indian Welfare and Inequality in the 20th Century

OpenAIRE

Guntupalli, Aravinda Meera

2007-01-01

The major aim of this research is to contribute new ideas and insights regarding Indian welfare and inequality from 1900 to 2000. Using mean heights and coefficients of variation in height of various groups – defined by region, caste and religion - welfare and inequality were investigated. Moreover, to study contemporary welfare, the body mass index was used in the final chapter. The overall welfare of Indians did not change considerably from 1914-74. There was no significant improvement in I...

Parabolic Equation Modeling of Propagation over Terrain Using Digital Elevation Model

Directory of Open Access Journals (Sweden)

Xiao-Wei Guan

2018-01-01

Full Text Available The parabolic equation method based on digital elevation model (DEM is applied on propagation predictions over irregular terrains. Starting from a parabolic approximation to the Helmholtz equation, a wide-angle parabolic equation is deduced under the assumption of forward propagation and the split-step Fourier transform algorithm is used to solve it. The application of DEM is extended to the Cartesian coordinate system and expected to provide a precise representation of a three-dimensional surface with high efficiency. In order to validate the accuracy, a perfectly conducting Gaussian terrain profile is simulated and the results are compared with the shift map. As a consequence, a good agreement is observed. Besides, another example is given to provide a theoretical basis and reference for DEM selection. The simulation results demonstrate that the prediction errors will be obvious only when the resolution of the DEM used is much larger than the range step in the PE method.

Correlations in star networks: from Bell inequalities to network inequalities

International Nuclear Information System (INIS)

Tavakoli, Armin; Renou, Marc Olivier; Gisin, Nicolas; Brunner, Nicolas

2017-01-01

The problem of characterizing classical and quantum correlations in networks is considered. Contrary to the usual Bell scenario, where distant observers share a physical system emitted by one common source, a network features several independent sources, each distributing a physical system to a subset of observers. In the quantum setting, the observers can perform joint measurements on initially independent systems, which may lead to strong correlations across the whole network. In this work, we introduce a technique to systematically map a Bell inequality to a family of Bell-type inequalities bounding classical correlations on networks in a star-configuration. Also, we show that whenever a given Bell inequality can be violated by some entangled state ρ , then all the corresponding network inequalities can be violated by considering many copies of ρ distributed in the star network. The relevance of these ideas is illustrated by applying our method to a specific multi-setting Bell inequality. We derive the corresponding network inequalities, and study their quantum violations. (paper)

Growing gaps: The importance of income and family for educational inequalities in mortality among Swedish men and women 1990-2009.

Science.gov (United States)

Östergren, Olof

2015-08-01

Although absolute levels of mortality have decreased among Swedish men and women in recent decades, educational inequalities in mortality have increased, especially among women. The aim of this study is to disentangle the role of income and family type in educational inequalities in mortality in Sweden during 1990-2009, focusing on gender differences. Data on individuals born in Sweden between the ages of 30 and 74 years were collected from total population registries, covering a total of 529,275 deaths and 729 million person-months. Temporary life expectancies (age 30-74 years) by education were calculated using life tables, and rate ratios were estimated with Poisson regression with robust standard errors. Temporary life expectancy improved among all groups except low educated women. Relative educational inequalities in mortality (RRs) increased from 1.79 to 1.98 among men and from 1.78 to 2.10 among women. Variation in family type explained some of the inequalities among men, but not among women, and did not contribute to the trend. Variation in income explained a larger part of the educational inequalities among men compared to women and also explained the increase in educational inequalities in mortality among men and women. Increasing educational inequalities in mortality in Sweden may be attributed to the increase in income inequalities in mortality. © 2015 the Nordic Societies of Public Health.

A Generalized and Refined Perturbed Version of Ostrowski Type Inequalities

Directory of Open Access Journals (Sweden)

M. Z. Sarikaya

2017-01-01

Full Text Available In this paper, we first obtain a new identity for twice differentiable mappings. Then, we establish generalized and improved perturbed version of Ostrowski type inequalities for functions whose derivatives are of bounded variation or second derivatives are either bounded or Lipschitzian.

A Priori Regularity of Parabolic Partial Differential Equations

KAUST Repository

Berkemeier, Francisco

2018-01-01

In this thesis, we consider parabolic partial differential equations such as the heat equation, the Fokker-Planck equation, and the porous media equation. Our aim is to develop methods that provide a priori estimates for solutions with singular

Leggett–Garg inequalities

International Nuclear Information System (INIS)

Emary, Clive; Lambert, Neill; Nori, Franco

2014-01-01

In contrast to the spatial Bell's inequalities which probe entanglement between spatially separated systems, the Leggett–Garg inequalities test the correlations of a single system measured at different times. Violation of a genuine Leggett–Garg test implies either the absence of a realistic description of the system or the impossibility of measuring the system without disturbing it. Quantum mechanics violates the inequalities on both accounts and the original motivation for these inequalities was as a test for quantum coherence in macroscopic systems. The last few years has seen a number of experimental tests and violations of these inequalities in a variety of microscopic systems such as superconducting qubits, nuclear spins, and photons. In this article, we provide an introduction to the Leggett–Garg inequalities and review these latest experimental developments. We discuss important topics such as the significance of the non-invasive measurability assumption, the clumsiness loophole, and the role of weak measurements. Also covered are some recent theoretical proposals for the application of Leggett–Garg inequalities in quantum transport, quantum biology and nano-mechanical systems. (review article)

Temperature Performance Evaluation of Parabolic Dishes Covered ...

African Journals Online (AJOL)

Solar radiation reaching the earth is considered to be affected by some parameters like diffusion. This radiation is reflected or scattered by air molecules, cloud and aerosols (dust). Parabolic dishes made of different materials (glass, foil and painted surface) were used to concentrate energy on a copper calorimeter filled with ...

Social Inequalities in Body Weight and Physical Activity: Exploring the Role of Fitness Centers

Science.gov (United States)

McLaren, Lindsay; Rock, Melanie J.; McElgunn, Jamie

2012-01-01

Fitness centers are a viable option for physical activity, particularly in climates with significant weather variation. Due to variation in economic and social expressions of exclusivity, fitness centers may have some relation to social inequalities in physical inactivity and related health outcomes; thus, our objective was to explore this…

Immigration and income inequality

DEFF Research Database (Denmark)

Deding, Mette; Hussain, Azhar; Jakobsen, Vibeke

2010-01-01

During the last two decades most Western countries have experienced increased net immigration as well as increased income inequality. This article analyzes the effects on income inequality of an increased number of immigrants in Denmark and Germany for the 20- year period 1984-2003 and how...... the impact of the increased number of immigrants differs between the two countries. We find higher inequality for immigrants than natives in Denmark but vice versa for Germany. Over the period 1984-2003, this particular inequality gap has narrowed in both countries. At the same time, the contribution...... of immigrants to overall inequality has increased, primarily caused by increased between-group inequality. The share of immigrants in the population is more important for the change in overall inequality in Denmark than in Germany, while the opposite is the case for inequality among immigrants....

Elliptic and parabolic equations for measures

Energy Technology Data Exchange (ETDEWEB)

Bogachev, Vladimir I [M. V. Lomonosov Moscow State University, Moscow (Russian Federation); Krylov, Nikolai V [University of Minnesota, Minneapolis, MN (United States); Roeckner, Michael [Universitat Bielefeld, Bielefeld (Germany)

2009-12-31

This article gives a detailed account of recent investigations of weak elliptic and parabolic equations for measures with unbounded and possibly singular coefficients. The existence and differentiability of densities are studied, and lower and upper bounds for them are discussed. Semigroups associated with second-order elliptic operators acting in L{sup p}-spaces with respect to infinitesimally invariant measures are investigated. Bibliography: 181 titles.

Quasi-static responses and variational principles in gradient plasticity

Science.gov (United States)

Nguyen, Quoc-Son

2016-12-01

Gradient models have been much discussed in the literature for the study of time-dependent or time-independent processes such as visco-plasticity, plasticity and damage. This paper is devoted to the theory of Standard Gradient Plasticity at small strain. A general and consistent mathematical description available for common time-independent behaviours is presented. Our attention is focussed on the derivation of general results such as the description of the governing equations for the global response and the derivation of related variational principles in terms of the energy and the dissipation potentials. It is shown that the quasi-static response under a loading path is a solution of an evolution variational inequality as in classical plasticity. The rate problem and the rate minimum principle are revisited. A time-discretization by the implicit scheme of the evolution equation leads to the increment problem. An increment of the response associated with a load increment is a solution of a variational inequality and satisfies also a minimum principle if the energy potential is convex. The increment minimum principle deals with stables solutions of the variational inequality. Some numerical methods are discussed in view of the numerical simulation of the quasi-static response.

Schottky diode model for non-parabolic dispersion in narrow-gap semiconductor and few-layer graphene

Science.gov (United States)

Ang, Yee Sin; Ang, L. K.; Zubair, M.

Despite the fact that the energy dispersions are highly non-parabolic in many Schottky interfaces made up of 2D material, experimental results are often interpreted using the conventional Schottky diode equation which, contradictorily, assumes a parabolic energy dispersion. In this work, the Schottky diode equation is derived for narrow-gap semiconductor and few-layer graphene where the energy dispersions are highly non-parabolic. Based on Kane's non-parabolic band model, we obtained a more general Kane-Schottky scaling relation of J (T2 + γkBT3) which connects the contrasting J T2 in the conventional Schottky interface and the J T3 scaling in graphene-based Schottky interface via a non-parabolicity parameter, γ. For N-layer graphene of ABC -stacking and of ABA -stacking, the scaling relation follows J T 2 / N + 1 and J T3 respectively. Intriguingly, the Richardson constant extracted from the experimental data using an incorrect scaling can differ with the actual value by more than two orders of magnitude. Our results highlights the importance of using the correct scaling relation in order to accurately extract important physical properties, such as the Richardson constant and the Schottky barrier's height.

Peripherality, income inequality, and life expectancy: revisiting the income inequality hypothesis.

Science.gov (United States)

Moore, Spencer

2006-06-01

Recent criticisms of the income inequality and health hypothesis have stressed the lack of consistent significant evidence for the stronger effects of income inequality among rich countries. Despite such criticisms, little attention has been devoted to the income-based criteria underlying the stratification of countries into rich/poor groups and whether trade patterns and world-system role provide an alternative means of stratifying groups. To compare income-based and trade-based criteria, 107 countries were grouped into four typologies: (I) high/low income, (II) OECD membership/non-membership, (III) core/non-core, and (IV) non-periphery/periphery. Each typology was tested separately for significant differences in the effects of income inequality between groups. Separate group comparison tests and regression analyses were conducted for each typology using Rodgers (1979) specification of income, income inequality, and life expectancy. Interaction terms were introduced into Rodgers specification to test whether group classification moderated the effects of income inequality on health. Results show that the effects of income inequality are stronger in the periphery than non-periphery (IV) (-0.76 vs -0.23; P income inequality and population health have assumed (i) income differences between countries best capture global stratification and (ii) the negative effects of income inequality are stronger in high-income countries. However, present findings emphasize (i) the importance of measuring global stratification according to trading patterns and (ii) the strong, negative effects of income inequality on life expectancy among peripheral populations.

Stability test for a parabolic partial differential equation

NARCIS (Netherlands)

Vajta, Miklos

2001-01-01

The paper describes a stability test applied to coupled parabolic partial differential equations. The PDE's describe the temperature distribution of composite structures with linear inner heat sources. The distributed transfer functions are developed based on the transmission matrix of each layer.

Parabolic dune development modes according to shape at the southern fringes of the Hobq Desert, Inner Mongolia, China

Science.gov (United States)

Guan, Chao; Hasi, Eerdun; Zhang, Ping; Tao, Binbin; Liu, Dan; Zhou, Yanguang

2017-10-01

Since the 1970s, parabolic dunes at the southern fringe of the Hobq Desert, Inner Mongolia, China have exhibited many different shapes (V-shaped, U-shaped, and palmate) each with a unique mode of development. In the study area, parabolic dunes are mainly distributed in Regions A, B, and C with an intermittent river running from the south to the north. We used high-resolution remote-sensing images from 1970 to 2014 and RTK-GPS measurements to study the development modes of different dune shapes; the modes are characterized by the relationship between the intermittent river and dunes, formation of the incipient dune patterns, the predominant source supply of dunes, and the primary formation of different shapes (V-shaped, U-shaped, and palmate). Most parabolic dunes in Region A are V-shaped and closer to the bank of the river. The original barchans in this region exhibit "disconnected arms" behavior. With the sand blown out of the riverbed through gullies, the nebkhas on the disconnected arms acquire the external sand source through the "fertile island effect", thereby developing into triangular sand patches and further developing into V-shaped parabolic dunes. Most parabolic dunes in Regions B and C are palmate. The residual dunes cut by the re-channelization of river from transverse dune fields on the west bank are the main sand source of Region B. The parabolic dunes in Region C are the original barchans having then been transformed. The stoss slopes of V-shaped parabolic dunes along the riverbank are gradual and the dunes are flat in shape. The dune crest of V-shaped parabolic dune is the deposition area, which forms the "arc-shaped sand ridge". Their two arms are non-parallel; the lateral airflow of the arms jointly transport sand to the middle part of dunes, resulting in a narrower triangle that gradually becomes V-shaped. Palmate parabolic dunes have a steeper stoss slope and height. The dune crest of the palmate parabolic dune is the erosion area, which forms

Gradient remediability in linear distributed parabolic systems ...

African Journals Online (AJOL)

The aim of this paper is the introduction of a new concept that concerned the analysis of a large class of distributed parabolic systems. It is the general concept of gradient remediability. More precisely, we study with respect to the gradient observation, the existence of an input operator (gradient efficient actuators) ensuring ...

From general discrimination to segmented inequality: Migration and inequality in urban China.

Science.gov (United States)

Lu, Yao; Wang, Feng

2013-11-01

Internal migration in China during the last three decades, the largest in human history, offers a rare opportunity to understand inequalities in the making. Using data spanning 10years from China's largest metropolis, Shanghai, this study assesses how enduring state institutions interplay with the spread of market forces to shape income inequality between migrants and native urban workers. Though the wages of both Chinese migrants and urban workers rose considerably, economic restructuring during the decade under study resulted in diminished privileges for urbanites and subsequently increased collision between migrants and urban workers in the private sectors. These shifts, rather than substantially reducing inequality, have led to an evolving form of inequality, from an initial general blatant discrimination against migrants across the board, to a new and more subtle form of inequality characterized by substantial segmented discrimination against migrants within economic sectors, with the degree of inequality varying from sector to sector. We discuss how this changing inequality reflects complementary rather than competing roles of the state and market institutions in inequality creation and maintenance. Copyright © 2013 Elsevier Inc. All rights reserved.

Why reduce health inequalities?

Science.gov (United States)

Woodward, A; Kawachi, I

2000-12-01

It is well known that social, cultural and economic factors cause substantial inequalities in health. Should we strive to achieve a more even share of good health, beyond improving the average health status of the population? We examine four arguments for the reduction of health inequalities.1 Inequalities are unfair. Inequalities in health are undesirable to the extent that they are unfair, or unjust. Distinguishing between health inequalities and health inequities can be contentious. Our view is that inequalities become "unfair" when poor health is itself the consequence of an unjust distribution of the underlying social determinants of health (for example, unequal opportunities in education or employment).2 Inequalities affect everyone. Conditions that lead to marked health disparities are detrimental to all members of society. Some types of health inequalities have obvious spillover effects on the rest of society, for example, the spread of infectious diseases, the consequences of alcohol and drug misuse, or the occurrence of violence and crime.3 Inequalities are avoidable. Disparities in health are avoidable to the extent that they stem from identifiable policy options exercised by governments, such as tax policy, regulation of business and labour, welfare benefits and health care funding. It follows that health inequalities are, in principle, amenable to policy interventions. A government that cares about improving the health of the population ought therefore to incorporate considerations of the health impact of alternative options in its policy setting process.3 Interventions to reduce health inequalities are cost effective. Public health programmes that reduce health inequalities can also be cost effective. The case can be made to give priority to such programmes (for example, improving access to cervical cancer screening in low income women) on efficiency grounds. On the other hand, few programmes designed to reduce health inequalities have been formally

Integration of equations of parabolic type by the method of nets

CERN Document Server

Saul'Yev, V K; Stark, M; Ulam, S

1964-01-01

International Series of Monographs in Pure and Applied Mathematics, Volume 54: Integration of Equations of Parabolic Type by the Method of Nets deals with solving parabolic partial differential equations using the method of nets. The first part of this volume focuses on the construction of net equations, with emphasis on the stability and accuracy of the approximating net equations. The method of nets or method of finite differences (used to define the corresponding numerical method in ordinary differential equations) is one of many different approximate methods of integration of partial diff

Inequalities with applications to engineering

CERN Document Server

Cloud, Michael J; Lebedev, Leonid P

2014-01-01

This book offers a concise introduction to mathematical inequalities for graduate students and researchers in the fields of engineering and applied mathematics. It begins by reviewing essential facts from algebra and calculus and proceeds with a presentation of the central inequalities of applied analysis, illustrating a wide variety of practical applications. The text provides a gentle introduction to abstract spaces, such as metric, normed, and inner product spaces. It also provides full coverage of the central inequalities of applied analysis, such as Young's inequality, the inequality of the means, Hölder's inequality, Minkowski's inequality, the Cauchy–Schwarz inequality, Chebyshev's inequality, Jensen's inequality, and the triangle inequality. The second edition features extended coverage of applications, including continuum mechanics and interval analysis. It also includes many additional examples and exercises with hints and full solutions that may appeal to upper-level undergraduate and graduate...

Hardy type inequalities on time scales

CERN Document Server

Agarwal, Ravi P; Saker, Samir H

2016-01-01

The book is devoted to dynamic inequalities of Hardy type and extensions and generalizations via convexity on a time scale T. In particular, the book contains the time scale versions of classical Hardy type inequalities, Hardy and Littlewood type inequalities, Hardy-Knopp type inequalities via convexity, Copson type inequalities, Copson-Beesack type inequalities, Liendeler type inequalities, Levinson type inequalities and Pachpatte type inequalities, Bennett type inequalities, Chan type inequalities, and Hardy type inequalities with two different weight functions. These dynamic inequalities contain the classical continuous and discrete inequalities as special cases when T = R and T = N and can be extended to different types of inequalities on different time scales such as T = hN, h > 0, T = qN for q > 1, etc.In this book the authors followed the history and development of these inequalities. Each section in self-contained and one can see the relationship between the time scale versions of the inequalities and...

Modeling mode interactions in boundary layer flows via the Parabolized Floquet Equations

OpenAIRE

Ran, Wei; Zare, Armin; Hack, M. J. Philipp; Jovanović, Mihailo R.

2017-01-01

In this paper, we develop a linear model to study interactions between different modes in slowly-growing boundary layer flows. Our method consists of two steps. First, we augment the Blasius boundary layer profile with a disturbance field resulting from the linear Parabolized Stability Equations (PSE) to obtain the modified base flow; and, second, we combine Floquet analysis with the linear PSE to capture the spatial evolution of flow fluctuations. This procedure yields the Parabolized Floque...

Migration and regional inequality

DEFF Research Database (Denmark)

Peng, Lianqing; Swider, Sarah

2017-01-01

Scholars studying economic inequality in China have maintained that regional inequality and economic divergence across provinces have steadily increased over the past 30 years. New studies have shown that this trend is a statistical aberration; calculations show that instead of quickly and sharply...... rising, regional inequality has actually decreased, and most recently, remained stable. Our study suggests that China’s unique migratory regime is crucial to understanding these findings. We conduct a counterfactual simulation to demonstrate how migration and remittances have mitigated income inequality...... across provinces in order to show that without these processes, we would have seen more of a rise in interprovincial income inequality. We conclude by arguing that inequality in China is still increasing, but it is changing and becoming less place-based. As regional inequality decreases, there are signs...

From the Triangle Inequality to the Isoperimetric Inequality

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 2. From the Triangle Inequality to the Isoperimetric Inequality. S Kesavan. General Article Volume 19 Issue 2 February 2014 pp 135-148. Fulltext. Click here to view fulltext PDF. Permanent link:

Packing of equal discs on a parabolic spiral lattice

International Nuclear Information System (INIS)

Xudong, F.; Bursill, L.A.; Julin, P.

1989-01-01

A contact disc model is investigated to determine the most closely-packed parabolic spiral lattice. The most space-efficient packings have divergence angles in agreement with the priority ranking of natural spiral structures

Global income related health inequalities

Directory of Open Access Journals (Sweden)

Jalil Safaei

2007-01-01

Full Text Available Income related health inequalities have been estimated for various groups of individuals at local, state, or national levels. Almost all of theses estimates are based on individual data from sample surveys. Lack of consistent individual data worldwide has prevented estimates of international income related health inequalities. This paper uses the (population weighted aggregate data available from many countries around the world to estimate worldwide income related health inequalities. Since the intra-country inequalities are subdued by the aggregate nature of the data, the estimates would be those of the inter-country or international health inequalities. As well, the study estimates the contribution of major socioeconomic variables to the overall health inequalities. The findings of the study strongly support the existence of worldwide income related health inequalities that favor the higher income countries. Decompositions of health inequalities identify inequalities in both the level and distribution of income as the main source of health inequality along with inequalities in education and degree of urbanization as other contributing determinants. Since income related health inequalities are preventable, policies to reduce the income gaps between the poor and rich nations could greatly improve the health of hundreds of millions of people and promote global justice. Keywords: global, income, health inequality, socioeconomic determinants of health

Modeling, Simulation and Performance Evaluation of Parabolic Trough

African Journals Online (AJOL)

Mekuannint

Mekuannint Mesfin and Abebayehu Assefa. Department of Mechanical Engineering. Addis Ababa University ... off design weather conditions as well. Keywords: Parabolic Trough Collector (PTC);. Heat Transfer ... of a conventional Rankine cycle power plant with solar fields that are used to increase the temperature of heat ...

Modeling, Simulation and Performance Evaluation of Parabolic Trough

African Journals Online (AJOL)

Mekuannint

Heat Transfer Fluid (HTF); TRNSYS power plant model; STEC library; Solar Advisor Model (SAM);. TRNSYS solar field model; Solar Electric. Generation System (SEGS). INTRODUCTION. Parabolic troughs are currently most used means of power generation option of solar sources. Solar electric generation systems (SEGs) ...

A tour of inequality

Science.gov (United States)

Eliazar, Iddo

2018-02-01

This paper presents a concise and up-to-date tour to the realm of inequality indices. Originally devised for socioeconomic applications, inequality indices gauge the divergence of wealth distributions in human societies from the socioeconomic 'ground state' of perfect equality, i.e. pure communism. Inequality indices are quantitative scores that take values in the unit interval, with the zero score characterizing perfect equality. In effect, inequality indices are applicable in the context of general distributions of sizes - non-negative quantities such as count, length, area, volume, mass, energy, and duration. For general size distributions, which are omnipresent in science and engineering, inequality indices provide multi-dimensional and infinite-dimensional quantifications of the inherent inequality - i.e., the statistical heterogeneity, the non-determinism, the randomness. This paper compactly describes the insights and the practical implementation of inequality indices.

Inequality, Tolerance, and Growth

DEFF Research Database (Denmark)

Bjørnskov, Christian

This paper argues for the importance of individuals' tolerance of inequality for economic growth. By using the political ideology of governments as a measure of revealed tolerance of inequality, the paper shows that controlling for ideology improves the accuracy with which the effects of inequality...... are measured. Results show that inequality reduces growth but more so in societies where people perceive it as being relatively unfair. Further results indicate that legal quality and social trust are likely transmission channels for the effects of inequality....

Inequality, Tolerance, and Growth

DEFF Research Database (Denmark)

Bjørnskov, Christian

2004-01-01

This paper argues for the importance of individuals' tolerance of inequality for economic growth. By using the political ideology of governments as a measure of revealed tolerance of inequality, the paper shows that controlling for ideology improves the accuracy with which the effects of inequality...... are measured. Results show that inequality reduces growth but more so in societies where people perceive it as being relatively unfair. Further results indicate that legal quality and social trust are likely transmission channels for the effects of inequality....

The different worlds of inequality: Psychological determinants and implications of economic inequality

OpenAIRE

Steiniger, Tim

2015-01-01

Social and economic inequalities have been a concern in human societies throughout history. In recent years especially wealth and income inequality have been the focus of controversial public, political, and scientific debates. The present thesis seeks to contribute to the ongoing inequality debate by regarding economic inequality from a psychological point of view. Together with Detlef Fetchenhauer, Thomas Schlösser, and Daniel Ehlebracht, I experimentally investigated the psychological dete...

Rothe's method for parabolic equations on non-cylindrical domains

Czech Academy of Sciences Publication Activity Database

Dasht, J.; Engström, J.; Kufner, Alois; Persson, L.E.

2006-01-01

Roč. 1, č. 1 (2006), s. 59-80 ISSN 0973-2306 Institutional research plan: CEZ:AV0Z10190503 Keywords : parabolic equations * non-cylindrical domains * Rothe's method * time-discretization Subject RIV: BA - General Mathematics

Patterns of Socioeconomic Inequality in Adolescent Health Differ According to the Measure of Socioeconomic Position

DEFF Research Database (Denmark)

Elgar, Frank J.; McKinnon, Britt; Torsheim, Torbjorn

2016-01-01

Socioeconomic differences in health are ubiquitous across age groups, cultures, and health domains. However, variation in the size and pattern of health inequalities appears to relate to the measure of socioeconomic position (SEP) applied. Little attention has been paid to these differences...... in adolescents and their implications for health surveillance and policy. We examined health inequalities in 1371 adolescents in seven European countries using four measures of SEP: youth-reported material assets and subjective social status and parent-reported material assets and household income. For each SEP...... variable, we estimated risk ratios, risk differences, concentration curves, and concentration indices of inequality for fair/poor self-rated health and low life satisfaction. Results showed that inequalities in health and life satisfaction were largest when subjective social status was used as the SEP...

Physiologic Pressure and Flow Changes During Parabolic Flight (Pilot Study)

Science.gov (United States)

Pantalos, George; Sharp, M. Keith; Mathias, John R.; Hargens, Alan R.; Watenpaugh, Donald E.; Buckey, Jay C.

1999-01-01

The objective of this study was to obtain measurement of cutaneous tissue perfusion central and peripheral venous pressure, and esophageal and abdominal pressure in human test subjects during parabolic flight. Hemodynamic data recorded during SLS-I and SLS-2 missions have resulted in the paradoxical finding of increased cardiac stroke volume in the presence of a decreased central venous pressure (CVP) following entry in weightlessness. The investigators have proposed that in the absence of gravity, acceleration-induced peripheral vascular compression is relieved, increasing peripheral vascular capacity and flow while reducing central and peripheral venous pressure, This pilot study seeks to measure blood pressure and flow in human test subjects during parabolic flight for different postures.

A parabolic-hyperbolic system modelling a moving cell

Directory of Open Access Journals (Sweden)

Fabiana Cardetti

2009-08-01

Full Text Available In this article, we study the existence and uniqueness of local solutions for a moving boundary problem governed by a coupled parabolic-hyperbolic system. The results can be applied to cell movement, extending a result obtained by Choi, Groulx, and Lui in 2005.

Several applications of Cartwright-Field's inequality

OpenAIRE

Minculete, Nicuşor; Furuichi, Shigeru

2011-01-01

In this paper we present several applications of Cartwright-Field's inequality. Among these we found Young's inequality, Bernoulli's inequality, the inequality between the weighted power means, H\\"{o}lder's inequality and Cauchy's inequality. We give also two applications related to arithmetic functions and to operator inequalities.

Modeling of the pyrolysis of biomass under parabolic and exponential temperature increases using the Distributed Activation Energy Model

International Nuclear Information System (INIS)

Soria-Verdugo, Antonio; Goos, Elke; Arrieta-Sanagustín, Jorge; García-Hernando, Nestor

2016-01-01

Highlights: • Pyrolysis of biomass under parabolic and exponential temperature profiles is modeled. • The model is based on a simplified Distributed Activation Energy Model. • 4 biomasses are analyzed in TGA with parabolic and exponential temperature increases. • Deviations between the model prediction and TGA measurements are under 5 °C. - Abstract: A modification of the simplified Distributed Activation Energy Model is proposed to simulate the pyrolysis of biomass under parabolic and exponential temperature increases. The pyrolysis of pine wood, olive kernel, thistle flower and corncob was experimentally studied in a TGA Q500 thermogravimetric analyzer. The results of the measurements of nine different parabolic and exponential temperature increases for each sample were employed to validate the models proposed. The deviation between the experimental TGA measurements and the estimation of the reacted fraction during the pyrolysis of the four samples under parabolic and exponential temperature increases was lower than 5 °C for all the cases studied. The models derived in this work to describe the pyrolysis of biomass with parabolic and exponential temperature increases were found to be in good agreement with the experiments conducted in a thermogravimetric analyzer.

Bell's inequalities for quantum mechanics

International Nuclear Information System (INIS)

Andaas, H.E.

1991-10-01

Inequalities corresponding to the generalized Bell's inequalities of local realism are derived for the quantum case. The extremal values permitted by these inequalities exceed those allowed by the generalized Bell's inequalities. Quantum predictions for systems of two spin-1/2 particles prepared as mixtures do not violate Bell's inequalities. 15 refs

Generalized Second Law of Thermodynamics in Parabolic LTB Inhomogeneous Cosmology

International Nuclear Information System (INIS)

Sheykhi, A.; Moradpour, H.; Sarab, K. Rezazadeh; Wang, B.

2015-01-01

We study thermodynamics of the parabolic Lemaitre–Tolman–Bondi (LTB) cosmology supported by a perfect fluid source. This model is the natural generalization of the flat Friedmann–Robertson–Walker (FRW) universe, and describes an inhomogeneous universe with spherical symmetry. After reviewing some basic equations in the parabolic LTB cosmology, we obtain a relation for the deceleration parameter in this model. We also obtain a condition for which the universe undergoes an accelerating phase at the present time. We use the first law of thermodynamics on the apparent horizon together with the Einstein field equations to get a relation for the apparent horizon entropy in LTB cosmology. We find out that in LTB model of cosmology, the apparent horizon's entropy could be feeded by a term, which incorporates the effects of the inhomogeneity. We consider this result and get a relation for the total entropy evolution, which is used to examine the generalized second law of thermodynamics for an accelerating universe. We also verify the validity of the second law and the generalized second law of thermodynamics for a universe filled with some kinds of matters bounded by the event horizon in the framework of the parabolic LTB model. (paper)

Design and experimental investigation of a stretched parabolic linear Fresnel reflector collecting system

International Nuclear Information System (INIS)

Zhu, Yanqing; Shi, Jifu; Li, Yujian; Wang, Leilei; Huang, Qizhang; Xu, Gang

2016-01-01

Highlights: • A parabolic primary mirror field is designed to reduce the gap between adjacent mirrors. • The movable receiver can reduce the end losses. • The thermal efficiency of 66% is achieved at Guangzhou in winter. - Abstract: This paper proposes a stretched parabolic linear Fresnel reflector (SPLFR) collecting system. The primary optical mirror field of the SPLFR collecting system and the second-stage concentrator of compound parabolic collector are designed. The mirrors located at the parabolic line are close to each other, which effectively reduce the gap between the adjacent mirrors. The end losses of the receiver are very important, especially in a small-scale collecting system. A movable receiver is introduced for the reduction of the end losses. Moreover, a stretched structure of SPLFR is designed for wind resistance. Finally, the thermal performance of the SPLFR collecting system with fixed and movable receiver located in Guangzhou is tested. The maximum thermal efficiency obtained by this collecting system with movable receiver is 66% which avoid the end losses effectively, and the solar collector thermal loss coefficient is 1.32 W/m"2 °C. The results show that the SPLFR collecting system has excellent thermal performance and a promising application future. Meanwhile, this system will provide a valuable reference for concentrating solar power technology.

Measuring Geographic Inequalities: Dealing with Multiple Health Resources by Data Envelopment Analysis.

Science.gov (United States)

Dlouhý, Martin

2018-01-01

The existence of geographic differences in health resources, health expenditures, the utilization of health services, and health outcomes have been documented by a lot of studies from various countries of the world. In a publicly financed health system, equal access is one of the main objectives of the national health policy. That is why inequalities in the geographic allocation of health resources are an important health policy issue. Measures of inequality express the complexity of variation in the observed variable by a single number, and there is a variety of inequality measures available. The objective of this study is to develop a measure of the geographic inequality in the case of multiple health resources. The measure uses data envelopment analysis (DEA), which is a non-parametric method of production function estimation, to transform multiple resources into a single virtual health resource. The study shows that the DEA originally developed for measuring efficiency can be used successfully to measure inequality. For the illustrative purpose, the inequality measure is calculated for the Czech Republic. The values of separate Robin Hood Indexes (RHIs) are 6.64% for physicians and 3.96% for nurses. In the next step, we use combined RHI for both health resources. Its value 5.06% takes into account that the combinations of two health resources serve regional populations.

Measuring Geographic Inequalities: Dealing with Multiple Health Resources by Data Envelopment Analysis

Science.gov (United States)

Dlouhý, Martin

2018-01-01

The existence of geographic differences in health resources, health expenditures, the utilization of health services, and health outcomes have been documented by a lot of studies from various countries of the world. In a publicly financed health system, equal access is one of the main objectives of the national health policy. That is why inequalities in the geographic allocation of health resources are an important health policy issue. Measures of inequality express the complexity of variation in the observed variable by a single number, and there is a variety of inequality measures available. The objective of this study is to develop a measure of the geographic inequality in the case of multiple health resources. The measure uses data envelopment analysis (DEA), which is a non-parametric method of production function estimation, to transform multiple resources into a single virtual health resource. The study shows that the DEA originally developed for measuring efficiency can be used successfully to measure inequality. For the illustrative purpose, the inequality measure is calculated for the Czech Republic. The values of separate Robin Hood Indexes (RHIs) are 6.64% for physicians and 3.96% for nurses. In the next step, we use combined RHI for both health resources. Its value 5.06% takes into account that the combinations of two health resources serve regional populations. PMID:29541631

Piecewise parabolic negative magnetoresistance of two-dimensional electron gas with triangular antidot lattice

International Nuclear Information System (INIS)

Budantsev, M. V.; Lavrov, R. A.; Pogosov, A. G.; Zhdanov, E. Yu.; Pokhabov, D. A.

2011-01-01

Extraordinary piecewise parabolic behavior of the magnetoresistance has been experimentally detected in the two-dimensional electron gas with a dense triangular lattice of antidots, where commensurability magnetoresistance oscillations are suppressed. The magnetic field range of 0–0.6 T can be divided into three wide regions, in each of which the magnetoresistance is described by parabolic dependences with high accuracy (comparable to the experimental accuracy) and the transition regions between adjacent regions are much narrower than the regions themselves. In the region corresponding to the weakest magnetic fields, the parabolic behavior becomes almost linear. The observed behavior is reproducible as the electron gas density changes, which results in a change in the resistance by more than an order of magnitude. Possible physical mechanisms responsible for the observed behavior, including so-called “memory effects,” are discussed.

Parabolic versus spherical partial cross sections for photoionization excitation of He near threshold

International Nuclear Information System (INIS)

Bouri, C.; Selles, P.; Malegat, L.; Kwato Njock, M. G.

2006-01-01

Spherical and parabolic partial cross sections and asymmetry parameters, defined in the ejected electron frame, are presented for photoionization excitation of the helium atom at 0.1 eV above its double ionization threshold. A quantitative law giving the dominant spherical partial wave l dom for each excitation level n is obtained. The parabolic partial cross sections are shown to satisfy the same approximate selection rules as the related Rydberg series of doubly excited states (K,T) n A . The analysis of radial and angular correlations reveals the close relationship between double excitation, ionization excitation, and double ionization. Opposite to a widespread belief, the observed value of the asymmetry parameter is shown to result from the interplay of radial correlations and symmetry constraints, irrespective of angular correlations. Finally, the measurement of parabolic partial cross sections is proposed as a challenge to experimentalists

Income Inequality and Education

Directory of Open Access Journals (Sweden)

Richard Breen

2015-08-01

Full Text Available Many commentators have seen the growing gap in earnings and income between those with a college education and those without as a major cause of increasing inequality in the United States and elsewhere. In this article we investigate the extent to which increasing the educational attainment of the US population might ameliorate inequality. We use data from NLSY79 and carry out a three-level decomposition of total inequality into within-person, between-person and between-education parts. We find that the between-education contribution to inequality is small, even when we consider only adjusted inequality that omits the within-person component. We carry out a number of simulations to gauge the likely impact on inequality of changes in the distribution of education and of a narrowing of the differences in average incomes between those with different levels of education. We find that any feasible educational policy is likely to have only a minor impact on income inequality.

A scalable variational inequality approach for flow through porous media models with pressure-dependent viscosity

Science.gov (United States)

Mapakshi, N. K.; Chang, J.; Nakshatrala, K. B.

2018-04-01

Mathematical models for flow through porous media typically enjoy the so-called maximum principles, which place bounds on the pressure field. It is highly desirable to preserve these bounds on the pressure field in predictive numerical simulations, that is, one needs to satisfy discrete maximum principles (DMP). Unfortunately, many of the existing formulations for flow through porous media models do not satisfy DMP. This paper presents a robust, scalable numerical formulation based on variational inequalities (VI), to model non-linear flows through heterogeneous, anisotropic porous media without violating DMP. VI is an optimization technique that places bounds on the numerical solutions of partial differential equations. To crystallize the ideas, a modification to Darcy equations by taking into account pressure-dependent viscosity will be discretized using the lowest-order Raviart-Thomas (RT0) and Variational Multi-scale (VMS) finite element formulations. It will be shown that these formulations violate DMP, and, in fact, these violations increase with an increase in anisotropy. It will be shown that the proposed VI-based formulation provides a viable route to enforce DMP. Moreover, it will be shown that the proposed formulation is scalable, and can work with any numerical discretization and weak form. A series of numerical benchmark problems are solved to demonstrate the effects of heterogeneity, anisotropy and non-linearity on DMP violations under the two chosen formulations (RT0 and VMS), and that of non-linearity on solver convergence for the proposed VI-based formulation. Parallel scalability on modern computational platforms will be illustrated through strong-scaling studies, which will prove the efficiency of the proposed formulation in a parallel setting. Algorithmic scalability as the problem size is scaled up will be demonstrated through novel static-scaling studies. The performed static-scaling studies can serve as a guide for users to be able to select

Country-level predictors of vaccination coverage and inequalities in Gavi-supported countries.

Science.gov (United States)

Arsenault, Catherine; Johri, Mira; Nandi, Arijit; Mendoza Rodríguez, José M; Hansen, Peter M; Harper, Sam

2017-04-25

Important inequalities in childhood vaccination coverage persist between countries and population groups. Understanding why some countries achieve higher and more equitable levels of coverage is crucial to redress these inequalities. In this study, we explored the country-level determinants of (1) coverage of the third dose of diphtheria-tetanus-pertussis- (DTP3) containing vaccine and (2) within-country inequalities in DTP3 coverage in 45 countries supported by Gavi, the Vaccine Alliance. We used data from the most recent Demographic and Health Surveys (DHS) conducted between 2005 and 2014. We measured national DTP3 coverage and the slope index of inequality in DTP3 coverage with respect to household wealth, maternal education, and multidimensional poverty. We collated data on country health systems, health financing, governance and geographic and sociocultural contexts from published sources. We used meta-regressions to assess the relationship between these country-level factors and variations in DTP3 coverage and inequalities. To validate our findings, we repeated these analyses for coverage with measles-containing vaccine (MCV). We found considerable heterogeneity in DTP3 coverage and in the magnitude of inequalities across countries. Results for MCV were consistent with those from DTP3. Political stability, gender equality and smaller land surface were important predictors of higher and more equitable levels of DTP3 coverage. Inequalities in DTP3 coverage were also lower in countries receiving more external resources for health, with lower rates of out-of-pocket spending and with higher national coverage. Greater government spending on heath and lower linguistic fractionalization were also consistent with better vaccination outcomes. Improving vaccination coverage and reducing inequalities requires that policies and programs address critical social determinants of health including geographic and social exclusion, gender inequality and the availability of

Linear inequalities and overlap bounds: a novel use of an operator inequality

International Nuclear Information System (INIS)

Cohen, M.; Leopold, J.G.

1976-01-01

Bounds to overlap integrals are obtained by an operator inequality technique. The formulation involves a set of linear inequalities with several overlap integrals as unknowns. The 'solution' of this set of inequalities leads to bound expressions which complement those of other workers. (author)

All inequality is not equal: children correct inequalities using resource value

Science.gov (United States)

Shaw, Alex; Olson, Kristina R.

2013-01-01

Fairness concerns guide children's judgments about how to share resources with others. However, it is unclear from past research if children take extant inequalities or the value of resources involved in an inequality into account when sharing with others; these questions are the focus of the current studies. In all experiments, children saw an inequality between two recipients—one had two more resources than another. What varied between conditions was the value of the resources that the child could subsequently distribute. When the resources were equal in value to those involved in the original inequality, children corrected the previous inequality by giving two resources to the child with fewer resources (Experiment 1). However, as the value of the resources increased relative to those initially shared by the experimenter, children were more likely to distribute the two high value resources equally between the two recipients, presumably to minimize the overall inequality in value (Experiments 1 and 2). We found that children specifically use value, not just size, when trying to equalize outcomes (Experiment 3) and further found that children focus on the relative rather than absolute value of the resources they share—when the experimenter had unequally distributed the same high value resource that the child would later share, children corrected the previous inequality by giving two high value resources to the person who had received fewer high value resources. These results illustrate that children attempt to correct past inequalities and try to maintain equality not just in the count of resources but also by using the value of resources. PMID:23882227

Inequality in CO2 emissions across countries and its relationship with income inequality: A distributive approach

International Nuclear Information System (INIS)

Padilla, Emilio; Serrano, Alfredo

2006-01-01

This paper analyzes the inequality in CO 2 emissions across countries (and groups of countries) and the relationship of this inequality with income inequality across countries for the period (1971-1999). The research employs the tools that are usually applied in income distribution analysis. The methodology used here gives qualitative and quantitative information on some of the features of the inequalities across countries that are considered most relevant for the design and discussion of policies aimed at mitigating climate change. The paper studies the relationship between CO 2 emissions and GDP and shows that income inequality across countries has been followed by an important inequality in the distribution of emissions. This inequality has diminished mildly, although the inequality in emissions across countries ordered in the increasing value of income (inequality between rich and poor countries) has diminished less than the 'simple' inequality in emissions. Lastly, the paper shows that the inequality in CO 2 emissions is mostly explained by the inequality between groups with different per capita income level. The importance of the inequality within groups of similar per capita income is much lower and has diminished during the period, especially in the low middle income group

Inequalities an approach through problems

CERN Document Server

Venkatachala, B J

2018-01-01

This book discusses about the basic topics on inequalities and their applications. These include the arithmetic mean–geometric mean inequality, Cauchy–Schwarz inequality, Chebyshev inequality, rearrangement inequality, convex and concave functions and Muirhead's theorem. The book contains over 400 problems with their solutions. A chapter on geometric inequalities is a special feature of this book. Most of these problems are from International Mathematical Olympiads and from many national mathematical Olympiads. The book is intended to help students who are preparing for various mathematical competitions. It is also a good source book for graduate students who are consolidating their knowledge of inequalities and their applications. .

Shock wave convergence in water with parabolic wall boundaries

International Nuclear Information System (INIS)

Yanuka, D.; Shafer, D.; Krasik, Ya.

2015-01-01

The convergence of shock waves in water, where the cross section of the boundaries between which the shock wave propagates is either straight or parabolic, was studied. The shock wave was generated by underwater electrical explosions of planar Cu wire arrays using a high-current generator with a peak output current of ∼45 kA and rise time of ∼80 ns. The boundaries of the walls between which the shock wave propagates were symmetric along the z axis, which is defined by the direction of the exploding wires. It was shown that with walls having a parabolic cross section, the shock waves converge faster and the pressure in the vicinity of the line of convergence, calculated by two-dimensional hydrodynamic simulations coupled with the equations of state of water and copper, is also larger

Optimal linear-quadratic control of coupled parabolic-hyperbolic PDEs

Science.gov (United States)

Aksikas, I.; Moghadam, A. Alizadeh; Forbes, J. F.

2017-10-01

This paper focuses on the optimal control design for a system of coupled parabolic-hypebolic partial differential equations by using the infinite-dimensional state-space description and the corresponding operator Riccati equation. Some dynamical properties of the coupled system of interest are analysed to guarantee the existence and uniqueness of the solution of the linear-quadratic (LQ)-optimal control problem. A state LQ-feedback operator is computed by solving the operator Riccati equation, which is converted into a set of algebraic and differential Riccati equations, thanks to the eigenvalues and the eigenvectors of the parabolic operator. The results are applied to a non-isothermal packed-bed catalytic reactor. The LQ-optimal controller designed in the early portion of the paper is implemented for the original nonlinear model. Numerical simulations are performed to show the controller performances.

Bell inequalities stronger than the Clauser-Horne-Shimony-Holt inequality for three-level isotropic states

International Nuclear Information System (INIS)

Ito, Tsuyoshi; Imai, Hiroshi; Avis, David

2006-01-01

We show that some two-party Bell inequalities with two-valued observables are stronger than the CHSH inequality for 3x3 isotropic states in the sense that they are violated by some isotropic states in the 3x3 system that do not violate the CHSH inequality. These Bell inequalities are obtained by applying triangular elimination to the list of known facet inequalities of the cut polytope on nine points. This gives a partial solution to an open problem posed by Collins and Gisin. The results of numerical optimization suggest that they are candidates for being stronger than the I 3322 Bell inequality for 3x3 isotropic states. On the other hand, we found no Bell inequalities stronger than the CHSH inequality for 2x2 isotropic states. In addition, we illustrate an inclusion relation among some Bell inequalities derived by triangular elimination

Quantum crystal growing: adiabatic preparation of a bosonic antiferromagnet in the presence of a parabolic inhomogeneity

DEFF Research Database (Denmark)

Gammelmark, Søren; Eckardt, André

2013-01-01

felt by the two species. Using numerical simulations we predict that a finite parabolic potential can assist the adiabatic preparation of the antiferromagnet. The optimal strength of the parabolic inhomogeneity depends sensitively on the number imbalance between the two species. We also find...

Determinants of income inequality

OpenAIRE

Afandi, Akhsyim; Rantung, Vebryna Permatasari; Marashdeh, Hazem

2017-01-01

This study examines whether changing economic structure, social conditions, and financialization are responsible for increased income inequality in Indonesia. By employing panel data of 32 provinces in Indonesia that spans from 2007 to 2013, it finds that structural change affects income inequality, increased share of finance reduces inequality, which is against the financialization hypothesis, and social conditions have expected effects on income inequality. While an increased share of both ...

Incorporating concepts of inequality and inequity into health benefits analysis

Directory of Open Access Journals (Sweden)

Tuchmann Jessica L

2006-03-01

Full Text Available Abstract Background Although environmental policy decisions are often based in part on both risk assessment information and environmental justice concerns, formalized approaches for addressing inequality or inequity when estimating the health benefits of pollution control have been lacking. Inequality indicators that fulfill basic axioms and agree with relevant definitions and concepts in health benefits analysis and environmental justice analysis can allow for quantitative examination of efficiency-equality tradeoffs in pollution control policies. Methods To develop appropriate inequality indicators for health benefits analysis, we provide relevant definitions from the fields of risk assessment and environmental justice and consider the implications. We evaluate axioms proposed in past studies of inequality indicators and develop additional axioms relevant to this context. We survey the literature on previous applications of inequality indicators and evaluate five candidate indicators in reference to our proposed axioms. We present an illustrative pollution control example to determine whether our selected indicators provide interpretable information. Results and Conclusions We conclude that an inequality indicator for health benefits analysis should not decrease when risk is transferred from a low-risk to high-risk person, and that it should decrease when risk is transferred from a high-risk to low-risk person (Pigou-Dalton transfer principle, and that it should be able to have total inequality divided into its constituent parts (subgroup decomposability. We additionally propose that an ideal indicator should avoid value judgments about the relative importance of transfers at different percentiles of the risk distribution, incorporate health risk with evidence about differential susceptibility, include baseline distributions of risk, use appropriate geographic resolution and scope, and consider multiple competing policy alternatives. Given

Inequalities in Science

OpenAIRE

Xie, Y.

2014-01-01

Inequalities in scientists’ contributions to science and their rewards have always been very high. There are good reasons to propose that inequalities in science across research institutions and across individual scientists have increased in recent years. In the meantime, however, globalization and internet technology have narrowed inequalities in science across nations and facilitated the expansion of science and rapid production of scientific discoveries through international collaborative ...

Distribution-valued weak solutions to a parabolic problem arising in financial mathematics

Directory of Open Access Journals (Sweden)

Michael Eydenberg

2009-07-01

Full Text Available We study distribution-valued solutions to a parabolic problem that arises from a model of the Black-Scholes equation in option pricing. We give a minor generalization of known existence and uniqueness results for solutions in bounded domains $Omega subset mathbb{R}^{n+1}$ to give existence of solutions for certain classes of distributions $fin mathcal{D}'(Omega$. We also study growth conditions for smooth solutions of certain parabolic equations on $mathbb{R}^nimes (0,T$ that have initial values in the space of distributions.

Classification of conformal representations induced from the maximal cuspidal parabolic

Energy Technology Data Exchange (ETDEWEB)

Dobrev, V. K., E-mail: dobrev@inrne.bas.bg [Scuola Internazionale Superiore di Studi Avanzati (Italy)

2017-03-15

In the present paper we continue the project of systematic construction of invariant differential operators on the example of representations of the conformal algebra induced from the maximal cuspidal parabolic.

Almost monotonicity formulas for elliptic and parabolic operators with variable coefficients

KAUST Repository

Matevosyan, Norayr

2010-10-21

In this paper we extend the results of Caffarelli, Jerison, and Kenig [Ann. of Math. (2)155 (2002)] and Caffarelli and Kenig [Amer. J. Math.120 (1998)] by establishing an almost monotonicity estimate for pairs of continuous functions satisfying u± ≥ 0 Lu± ≥ -1, u+ · u_ = 0 ;in an infinite strip (global version) or a finite parabolic cylinder (localized version), where L is a uniformly parabolic operator Lu = LA,b,cu := div(A(x, s)∇u) + b(x,s) · ∇u + c(x,s)u - δsu with double Dini continuous A and uniformly bounded b and c. We also prove the elliptic counterpart of this estimate.This closes the gap between the known conditions in the literature (both in the elliptic and parabolic case) imposed on u± in order to obtain an almost monotonicity estimate.At the end of the paper, we demonstrate how to use this new almost monotonicity formula to prove the optimal C1,1-regularity in a fairly general class of quasi-linear obstacle-type free boundary problems. © 2010 Wiley Periodicals, Inc.

The inequality footprints of nations: a novel approach to quantitative accounting of income inequality.

Directory of Open Access Journals (Sweden)

Ali Alsamawi

Full Text Available In this study we use economic input-output analysis to calculate the inequality footprint of nations. An inequality footprint shows the link that each country's domestic economic activity has to income distribution elsewhere in the world. To this end we use employment and household income accounts for 187 countries and an historical time series dating back to 1990. Our results show that in 2010, most developed countries had an inequality footprint that was higher than their within-country inequality, meaning that in order to support domestic lifestyles, these countries source imports from more unequal economies. Amongst exceptions are the United States and United Kingdom, which placed them on a par with many developing countries. Russia has a high within-country inequality nevertheless it has the lowest inequality footprint in the world, which is because of its trade connections with the Commonwealth of Independent States and Europe. Our findings show that the commodities that are inequality-intensive, such as electronic components, chemicals, fertilizers, minerals, and agricultural products often originate in developing countries characterized by high levels of inequality. Consumption of these commodities may implicate within-country inequality in both developing and developed countries.

The inequality footprints of nations: a novel approach to quantitative accounting of income inequality.

Science.gov (United States)

Alsamawi, Ali; Murray, Joy; Lenzen, Manfred; Moran, Daniel; Kanemoto, Keiichiro

2014-01-01

In this study we use economic input-output analysis to calculate the inequality footprint of nations. An inequality footprint shows the link that each country's domestic economic activity has to income distribution elsewhere in the world. To this end we use employment and household income accounts for 187 countries and an historical time series dating back to 1990. Our results show that in 2010, most developed countries had an inequality footprint that was higher than their within-country inequality, meaning that in order to support domestic lifestyles, these countries source imports from more unequal economies. Amongst exceptions are the United States and United Kingdom, which placed them on a par with many developing countries. Russia has a high within-country inequality nevertheless it has the lowest inequality footprint in the world, which is because of its trade connections with the Commonwealth of Independent States and Europe. Our findings show that the commodities that are inequality-intensive, such as electronic components, chemicals, fertilizers, minerals, and agricultural products often originate in developing countries characterized by high levels of inequality. Consumption of these commodities may implicate within-country inequality in both developing and developed countries.

Individual Income, Area Deprivation, and Health: Do Income-Related Health Inequalities Vary by Small Area Deprivation?

Science.gov (United States)

Siegel, Martin; Mielck, Andreas; Maier, Werner

2015-11-01

This paper aims to explore potential associations between health inequalities related to socioeconomic deprivation at the individual and the small area level. We use German cross-sectional survey data for the years 2002 and 2006, and measure small area deprivation via the German Index of Multiple Deprivation. We test the differences between concentration indices of income-related and small area deprivation related inequalities in obesity, hypertension, and diabetes. Our results suggest that small area deprivation and individual income both yield inequalities in health favoring the better-off, where individual income-related inequalities are significantly more pronounced than those related to small area deprivation. We then apply a semiparametric extension of Wagstaff's corrected concentration index to explore how individual-level health inequalities vary with the degree of regional deprivation. We find that the concentration of obesity, hypertension, and diabetes among lower income groups also exists at the small area level. The degree of deprivation-specific income-related inequalities in the three health outcomes exhibits only little variations across different levels of multiple deprivation for both sexes. Copyright © 2014 John Wiley & Sons, Ltd.

Well-Posedness of Nonlocal Parabolic Differential Problems with Dependent Operators

Directory of Open Access Journals (Sweden)

Allaberen Ashyralyev

2014-01-01

Full Text Available The nonlocal boundary value problem for the parabolic differential equation v'(t+A(tv(t=f(t  (0≤t≤T,  v(0=v(λ+φ,  0<λ≤T in an arbitrary Banach space E with the dependent linear positive operator A(t is investigated. The well-posedness of this problem is established in Banach spaces C0β,γ(Eα-β of all Eα-β-valued continuous functions φ(t on [0,T] satisfying a Hölder condition with a weight (t+τγ. New Schauder type exact estimates in Hölder norms for the solution of two nonlocal boundary value problems for parabolic equations with dependent coefficients are established.

[Intelligence and the explanation for socio-economic inequalities in health].

Science.gov (United States)

Huisman, M; Mackenbach, J P

2007-05-12

Attention is increasingly being paid to the role of cognitive ability to explain socio-economic inequalities in health. The universal socio-economic gradient in health, where each rung lower on the socio-economic ladder implies worse health, has still not been satisfactorily explained scientifically. Because cognitive ability is related to a multitude of social outcomes in a similarly graded manner, hypothesising that cognitive ability plays a major role in health inequalities by socio-economic status is appealing. Recent empirical studies have shown that at least part of socio-economic health inequalities can indeed be explained by differences in cognitive ability. However, this does not imply that we should be pessimistic about future attempts to break the chain that links socio-economic status and cognitive ability with health. During some life stages, environmental factors may be able to influence cognitive ability. Interventions may therefore be targeted in order to optimize these effects. In addition, there is evidence that cognitive ability is correlated with health-related behaviours such as smoking, excessive alcohol consumption and obesity. Therefore, another opportunity for reducing health inequalities related to cognitive ability and socio-economic status would be to develop tailored interventions to improve health-related behaviours in disadvantaged groups. However, the first priority is to further investigate the role of cognitive ability in health inequalities by examining various health outcomes, different age groups and variations across the life course.

Global Inequality: An Introduction

Directory of Open Access Journals (Sweden)

Michelle Bata

2015-08-01

Full Text Available Global inequality has been little analyzed by sociologists despite their claim to be the scienti?c experts most in charge of the study of human inequalities and social strati?cation. Most undergraduate courses on social inequalities study race, class and gender without ever acknowledging that the greatest inequalities are between those individuals and households that live in developed versus less developed societies. The amount of international inequality has vastly outweighed within country inequalities since at least the 1870s when a wave of economic globalization under the Pax Britannica increased average wages in the core while leaving most of the periphery and the semiperiphery at subsistence levels. Increasing inequality was one of the most important consequences of nineteenth century globalization, and this fact is pregnant with importance for those who seek to understand what the consequences of twentieth century globalization may be. Resistance to global capitalism and attacks on symbols of power are likely to increase, just as they did in the decades following the great expansion of trade and investment in the last decades of the nineteenth century. Research into the causes of increasing inequalities is thus extremely important for social scientists, policy makers and global citizens who need to understand how the world-system works in order to change it.

A Generalized Affine Isoperimetric Inequality

OpenAIRE

Chen, Wenxiong; Howard, Ralph; Lutwak, Erwin; Yang, Deane; Zhang, Gaoyong

2004-01-01

A purely analytic proof is given for an inequality that has as a direct consequence the two most important affine isoperimetric inequalities of plane convex geometry: The Blaschke-Santalo inequality and the affine isoperimetric inequality of affine differential geometry.

Parabolic dune reactivation and migration at Napeague, NY, USA: Insights from aerial and GPR imagery

Science.gov (United States)

Girardi, James D.; Davis, Dan M.

2010-02-01

Observations from mapping since the 19th century and aerial imagery since 1930 have been used to study changes in the aeolian geomorphology of coastal parabolic dunes over the last ~ 170 years in the Walking Dune Field, Napeague, NY. The five large parabolic dunes of the Walking Dune Field have all migrated across, or are presently interacting with, a variably forested area that has affected their migration, stabilization and morphology. This study has concentrated on a dune with a particularly complex history of stabilization, reactivation and migration. We have correlated that dune's surface evolution, as revealed by aerial imagery, with its internal structures imaged using 200 MHz and 500 MHz Ground Penetrating Radar (GPR) surveys. Both 2D (transect) and high-resolution 3D GPR imagery image downwind dipping bedding planes which can be grouped by apparent dip angle into several discrete packages of beds that reflect distinct decadal-scale episodes of dune reactivation and growth. From aerial and high resolution GPR imagery, we document a unique mode of reactivation and migration linked to upwind dune formation and parabolic dune interactions with forest trees. This study documents how dune-dune and dune-vegetation interactions have influenced a unique mode of blowout deposition that has alternated on a decadal scale between opposite sides of a parabolic dune during reactivation and migration. The pattern of recent parabolic dune reactivation and migration in the Walking Dune Field appears to be somewhat more complex, and perhaps more sensitive to subtle environmental pressures, than an idealized growth model with uniform deposition and purely on-axis migration. This pattern, believed to be prevalent among other parabolic dunes in the Walking Dune Field, may occur also in many other places where similar observational constraints are unavailable.

Association of Income Inequality With Pediatric Hospitalizations for Ambulatory Care-Sensitive Conditions.

Science.gov (United States)

Bettenhausen, Jessica L; Colvin, Jeffrey D; Berry, Jay G; Puls, Henry T; Markham, Jessica L; Plencner, Laura M; Krager, Molly K; Johnson, Matthew B; Queen, Mary Ann; Walker, Jacqueline M; Latta, Grant M; Riss, Robert R; Hall, Matt

2017-06-05

The level of income inequality (ie, the variation in median household income among households within a geographic area), in addition to family-level income, is associated with worsened health outcomes in children. To determine the influence of income inequality on pediatric hospitalization rates for ambulatory care-sensitive conditions (ACSCs) and whether income inequality affects use of resources per hospitalization for ACSCs. This retrospective, cross-sectional analysis used the 2014 State Inpatient Databases of the Healthcare Cost and Utilization Project of 14 states to evaluate all hospital discharges for patients aged 0 to 17 years (hereafter referred to as children) from January 1 through December 31, 2014. Using the 2014 American Community Survey (US Census), income inequality (Gini index; range, 0 [perfect equality] to 1.00 [perfect inequality]), median household income, and total population of children aged 0 to 17 years for each zip code in the 14 states were measured. The Gini index for zip codes was divided into quartiles for low, low-middle, high-middle, and high income inequality. Rate, length of stay, and charges for pediatric hospitalizations for ACSCs. A total of 79 275 hospitalizations for ACSCs occurred among the 21 737 661 children living in the 8375 zip codes in the 14 included states. After adjustment for median household income and state of residence, ACSC hospitalization rates per 10 000 children increased significantly as income inequality increased from low (27.2; 95% CI, 26.5-27.9) to low-middle (27.9; 95% CI, 27.4-28.5), high-middle (29.2; 95% CI, 28.6-29.7), and high (31.8; 95% CI, 31.2-32.3) categories (P inequality (2.5 days; 95% CI, 2.4-2.5 days) compared with low inequality (2.4 days; 95% CI, 2.4-2.5 days; P income inequality have higher rates of hospitalizations for ACSCs. Consideration of income inequality, in addition to income level, may provide a better understanding of the complex relationship between socioeconomic

OPTIMAL ESTIMATES FOR THE SEMIDISCRETE GALERKIN METHOD APPLIED TO PARABOLIC INTEGRO-DIFFERENTIAL EQUATIONS WITH NONSMOOTH DATA

KAUST Repository

GOSWAMI, DEEPJYOTI; PANI, AMIYA K.; YADAV, SANGITA

2014-01-01

AWe propose and analyse an alternate approach to a priori error estimates for the semidiscrete Galerkin approximation to a time-dependent parabolic integro-differential equation with nonsmooth initial data. The method is based on energy arguments combined with repeated use of time integration, but without using parabolic-type duality techniques. An optimal L2-error estimate is derived for the semidiscrete approximation when the initial data is in L2. A superconvergence result is obtained and then used to prove a maximum norm estimate for parabolic integro-differential equations defined on a two-dimensional bounded domain. © 2014 Australian Mathematical Society.

Structured inverse modeling in parabolic diffusion processess

OpenAIRE

Schulz, Volker; Siebenborn, Martin; Welker, Kathrin

2014-01-01

Often, the unknown diffusivity in diffusive processes is structured by piecewise constant patches. This paper is devoted to efficient methods for the determination of such structured diffusion parameters by exploiting shape calculus. A novel shape gradient is derived in parabolic processes. Furthermore quasi-Newton techniques are used in order to accelerate shape gradient based iterations in shape space. Numerical investigations support the theoretical results.

A parabolic analogue of the higher-order comparison theorem of De Silva and Savin

Science.gov (United States)

Banerjee, Agnid; Garofalo, Nicola

2016-01-01

We show that the quotient of two caloric functions which vanish on a portion of the lateral boundary of a H k + α domain is H k + α up to the boundary for k ≥ 2. In the case k = 1, we show that the quotient is in H 1 + α if the domain is assumed to be space-time C 1 , α regular. This can be thought of as a parabolic analogue of a recent important result in [8], and we closely follow the ideas in that paper. We also give counterexamples to the fact that analogous results are not true at points on the parabolic boundary which are not on the lateral boundary, i.e., points which are at the corner and base of the parabolic boundary.

Inequalities in Science

Science.gov (United States)

Xie, Y.

2014-01-01

Inequalities in scientists’ contributions to science and their rewards have always been very high. There are good reasons to propose that inequalities in science across research institutions and across individual scientists have increased in recent years. In the meantime, however, globalization and internet technology have narrowed inequalities in science across nations and facilitated the expansion of science and rapid production of scientific discoveries through international collaborative networks. PMID:24855244

Economic inequality increases risk taking.

Science.gov (United States)

Payne, B Keith; Brown-Iannuzzi, Jazmin L; Hannay, Jason W

2017-05-02

Rising income inequality is a global trend. Increased income inequality has been associated with higher rates of crime, greater consumer debt, and poorer health outcomes. The mechanisms linking inequality to poor outcomes among individuals are poorly understood. This research tested a behavioral account linking inequality to individual decision making. In three experiments ( n = 811), we found that higher inequality in the outcomes of an economic game led participants to take greater risks to try to achieve higher outcomes. This effect of unequal distributions on risk taking was driven by upward social comparisons. Next, we estimated economic risk taking in daily life using large-scale data from internet searches. Risk taking was higher in states with greater income inequality, an effect driven by inequality at the upper end of the income distribution. Results suggest that inequality may promote poor outcomes, in part, by increasing risky behavior.

Covariance Bell inequalities

Science.gov (United States)

Pozsgay, Victor; Hirsch, Flavien; Branciard, Cyril; Brunner, Nicolas

2017-12-01

We introduce Bell inequalities based on covariance, one of the most common measures of correlation. Explicit examples are discussed, and violations in quantum theory are demonstrated. A crucial feature of these covariance Bell inequalities is their nonlinearity; this has nontrivial consequences for the derivation of their local bound, which is not reached by deterministic local correlations. For our simplest inequality, we derive analytically tight bounds for both local and quantum correlations. An interesting application of covariance Bell inequalities is that they can act as "shared randomness witnesses": specifically, the value of the Bell expression gives device-independent lower bounds on both the dimension and the entropy of the shared random variable in a local model.

The First European Parabolic Flight Campaign with the Airbus A310 ZERO-G

Science.gov (United States)

Pletser, Vladimir; Rouquette, Sebastien; Friedrich, Ulrike; Clervoy, Jean-Francois; Gharib, Thierry; Gai, Frederic; Mora, Christophe

2016-12-01

Aircraft parabolic flights repetitively provide up to 23 seconds of reduced gravity during ballistic flight manoeuvres. Parabolic flights are used to conduct short microgravity investigations in Physical and Life Sciences and in Technology, to test instrumentation prior to space flights and to train astronauts before a space mission. The use of parabolic flights is complementary to other microgravity carriers (drop towers, sounding rockets), and preparatory to manned space missions on board the International Space Station and other manned spacecraft, such as Shenzhou and the future Chinese Space Station. After 17 years of using the Airbus A300 ZERO-G, the French company Novespace, a subsidiary of the ' Centre National d'Etudes Spatiales' (CNES, French Space Agency), based in Bordeaux, France, purchased a new aircraft, an Airbus A310, to perform parabolic flights for microgravity research in Europe. Since April 2015, the European Space Agency (ESA), CNES and the ` Deutsches Zentrum für Luft- und Raumfahrt e.V.' (DLR, the German Aerospace Center) use this new aircraft, the Airbus A310 ZERO-G, for research experiments in microgravity. The first campaign was a Cooperative campaign shared by the three agencies, followed by respectively a CNES, an ESA and a DLR campaign. This paper presents the new Airbus A310 ZERO-G and its main characteristics and interfaces for scientific experiments. The experiments conducted during the first European campaign are presented.

Inequality of Opportunity and Income Inequality in Nine Chinese Provinces, 1989-2006

DEFF Research Database (Denmark)

Eriksson, Tor Viking; Zhang, Yingqiang

2010-01-01

's own choices (''effort''). What is the relationship between income inequality and inequality of opportunity? For this purpose we use data from the China Health and Nutrition Survey collected from nine provinces during the period 1989 to 2006. The CHNS has detailed information about incomes and other...... factors enabling us to construct a host of circumstance and effort variables for the offspring. We find that China has a substantial degree of inequality of opportunity. Parental income and parents' type of employer explain about two thirds of the total inequality of opportunity. Notably, parental...

Building a parabolic solar concentrator prototype

International Nuclear Information System (INIS)

Escobar-Romero, J F M; Montiel, S Vazquez y; Granados-AgustIn, F; Rodriguez-Rivera, E; Martinez-Yanez, L; Cruz-Martinez, V M

2011-01-01

In order to not further degrade the environment, people have been seeking to replace non-renewable natural resources such as fossil fuels by developing technologies that are based on renewable resources. An example of these technologies is solar energy. In this paper, we show the building and test of a solar parabolic concentrator as a prototype for the production of steam that can be coupled to a turbine to generate electricity or a steam engine in any particular industrial process.

Legal Quality, Inequality, and Tolerance

DEFF Research Database (Denmark)

Bjørnskov, Christian

Previous findings suggest that income inequality leads to lower legal quality. This paper argues that voters' tolerance of inequality exerts an additional influence. Empirical findings suggest that inequality leads to lower legal quality due to its effect on trust while the tolerance of inequality...

Legal Quality, Inequality, and Tolerance

DEFF Research Database (Denmark)

Bjørnskov, Christian

2004-01-01

Previous findings suggest that income inequality leads to lower legal quality. This paper argues that voters' tolerance of inequality exerts an additional influence. Empirical findings suggest that inequality leads to lower legal quality due to its effect on trust while the tolerance of inequality...

Product spaces and Nelson's inequality

International Nuclear Information System (INIS)

Faris, W.G.

1976-01-01

Certain inequalities for unbounded linear operators in L 2 extend to product spaces. This product space property is used to give a new proof that Gross's inequality for matrices implies Nelson's inequality for ordinary differential operators, and that this in turn implies Nelson's inequality for partial differential operators in infinitely many dimensions. A new proof of Gross's inequality is given. There is also a discussion of the physical meaning of Nelson's inequality in quantum field theory. The article may serve as an introduction for non-specialists to some of the recent mathematical work in this subject. (Auth.)

Humidification dehumidification desalination system using parabolic trough solar air collector

International Nuclear Information System (INIS)

Al-Sulaiman, Fahad A.; Zubair, M. Ifras; Atif, Maimoon; Gandhidasan, Palanichamy; Al-Dini, Salem A.; Antar, Mohamed A.

2015-01-01

This paper deals with a detailed thermodynamic analysis to assess the performance of an HDH system with an integrated parabolic trough solar collector (PTSC). The HDH system considered is an open air, open water, air heated system that uses a PTSC as an air heater. Two different configurations were considered of the HDH system. In the first configuration, the solar air heater was placed before the humidifier whereas in the second configuration the solar air heater was placed between the humidifier and the dehumidifier. The current study revealed that PTSCs are well suited for air heated HDH systems for high radiation location, such as Dhahran, Saudi Arabia. The comparison between the two HDH configurations demonstrates that the gained output ratio (GOR) of the first configuration is, on average, about 1.5 whereas for the second configuration the GOR increases up to an average value of 4.7. The study demonstrates that the HDH configuration with the air heater placed between the humidifier and the dehumidifier has a better performance and a higher productivity. - Highlights: • Thermodynamic analysis of an HDH system driven by a parabolic trough solar collector was conducted. • The first configuration reveals a GOR of 1.5 while the second configuration reveals a GOR of 4.7. • Effective heating of the HDH system was obtained through parabolic trough solar collector

The impact of increasing income inequalities on educational inequalities in mortality - An analysis of six European countries.

Science.gov (United States)

Hoffmann, Rasmus; Hu, Yannan; de Gelder, Rianne; Menvielle, Gwenn; Bopp, Matthias; Mackenbach, Johan P

2016-07-08

Over the past decades, both health inequalities and income inequalities have been increasing in many European countries, but it is unknown whether and how these trends are related. We test the hypothesis that trends in health inequalities and trends in income inequalities are related, i.e. that countries with a stronger increase in income inequalities have also experienced a stronger increase in health inequalities. We collected trend data on all-cause and cause-specific mortality, as well as on the household income of people aged 35-79, for Belgium, Denmark, England & Wales, France, Slovenia, and Switzerland. We calculated absolute and relative differences in mortality and income between low- and high-educated people for several time points in the 1990s and 2000s. We used fixed-effects panel regression models to see if changes in income inequality predicted changes in mortality inequality. The general trend in income inequality between high- and low-educated people in the six countries is increasing, while the mortality differences between educational groups show diverse trends, with absolute differences mostly decreasing and relative differences increasing in some countries but not in others. We found no association between trends in income inequalities and trends in inequalities in all-cause mortality, and trends in mortality inequalities did not improve when adjusted for rising income inequalities. This result held for absolute as well as for relative inequalities. A cause-specific analysis revealed some association between income inequality and mortality inequality for deaths from external causes, and to some extent also from cardiovascular diseases, but without statistical significance. We find no support for the hypothesis that increasing income inequality explains increasing health inequalities. Possible explanations are that other factors are more important mediators of the effect of education on health, or more simply that income is not an important

A Review of Psycho-Physiological Responses to Parabolic Flight

Science.gov (United States)

Brummer, Vera; Schneider, Stefan; Guardiera, Simon; Struder, Heiko K.

2008-06-01

This review combines and correlates data of several studies conducted in the recent years where we were able to show an increase in stress hormone concentrations, EEG activity and a decrease in mood during parabolic flights. The aim of these studies was to consider whether previous results showing a decrease in mental and perceptual motor performance during weightlessness were solely due to the changes in gravity itself or were also, at least partly, explainable by an increase of stress and/or arousal during parabolic flights. A correlation between stress hormones and mood but not between EEG activity and mood nor between stress hormones and EEG activity could be found. We propose two different stressors: First an activation of the adrenomedullary system, secondly a general increase of cortical arousal. Whereas the first one is perceived by subjects, this is not the case for the second one.

Laser propagation and compton scattering in parabolic plasma channel

CERN Document Server

Dongguo, L; Yokoya, K; Hirose, T

2003-01-01

A Gaussian laser beam propagating in a parabolic plasma channel is discussed in this paper. For a weak laser, plasma density perturbation induced by interaction between the laser field and plasma is very small, the refractive index can be assumed to be constant with respect to time variable. For a parabolic plasma channel, through the static propagation equation, we obtain an analytical solution of the profile function of the Gaussian laser beam for an unmatched case and give the general condition for the matched case. As the laser intensity increases, an effect due to strong laser fields is included. We discuss how to design and select the distribution of plasma density for a certain experiment in which a plasma channel is utilized to guide a laser beam. The number of scattered photons (X-rays) generated through Compton backscattering in a plasma channel is discussed. (author)

Inequality of Opportunity in Egypt

OpenAIRE

Hassine, Nadia Belhaj

2012-01-01

The article evaluates the contribution of inequality of opportunity to earnings inequality in Egypt and analyzes its evolution across three time periods and different population groups. It provides parametric and nonparametric estimates of a lower bound for the degree of inequality of opportunity for wage and salary workers. On average, the contribution of opportunity-shaping circumstances to earnings inequality declined from 22 percent in 1988 to 15 percent in 2006. Levels of inequality of o...

Gender based within-household inequality in immunization status of children: some evidence from South Asian countries

OpenAIRE

Ashish Singh

2015-01-01

Using households with a pair of male-female siblings from DHS surveys, this paper estimates gender based within-household inequality in immunization status of children (aged 1-5 years) from Bangladesh, India, Nepal and Pakistan. I find substantial level of gender based within-household inequality in immunization status (with large inter-country variations) in the countries studied. Further, I estimate household fixed-effects models for immunization status and find significant difference betwe...

The Comparative Organizational Inequality Network: Toward an Economic Sociology of Inequality

OpenAIRE

Tomaskovic-Devey , Donald; Godechot, Olivier

2017-01-01

The international Comparative Organizational Inequality Network (COIN) asks: • What factors drive overall income inequality within and between workplaces? • How do workplaces exacerbate or mitigate the impact of individual distinctions, such as education level, gender, or immigrant status? • How do inequality-generating mechanisms vary as a function of institutional context? List of authors: Donald Tomaskovic-Devey with Nina Bandelj, Irene Boeckmann, István Boza, David Co...

Lorentz-invariant Bell's inequality

International Nuclear Information System (INIS)

Kim, Won Tae; Son, Edwin J.

2005-01-01

We study Bell's inequality in relation to the Einstein-Podolsky-Rosen paradox in the relativistic regime. For this purpose, a relativistically covariant analysis is used in the calculation of the Bell's inequality, which results in the maximally violated Bell's inequality in any reference frame

Processing of data from innovative parabolic strip telescope.

Science.gov (United States)

Kosejk, Vladislav; Novy, J.; Chadzitaskos, Goce

2015-12-01

This paper presents an innovative telescope design based on the usage of a parabolic strip fulfilling the function of an objective. Isaac Newton was the first to solve the problem of chromatic aberration, which is caused by a difference in the refractive index of lenses. This problem was solved by a new kind of telescope with a mirror used as an objective. There are many different kinds of telescopes. The most basic one is the lens telescope. This type of a telescope uses a set of lenses. Another type is the mirror telescope, which employs the concave mirror, spherical parabolic mirror or hyperbolically shaped mirror as its objective. The lens speed depends directly on the surface of a mirror. Both types can be combined to form a telescope composed of at least two mirrors and a set of lenses. The light is reflected from the primary mirror to the secondary one and then to the lens system. This type is smaller-sized, with a respectively reduced lens speed. The telescope design presented in this paper uses a parabolic strip fulfilling the function of an objective. Observed objects are projected as lines in a picture plane. Each of the lines of a size equal to the size of the strip corresponds to the sum of intensities of the light coming perpendicular to the objective from an observed object. A series of pictures taken with a different rotation and processed by a special reconstruction algorithm is needed to get 2D pictures. The telescope can also be used for fast detection of objects. In this mode, the rotation and multiple pictures are not needed, just one picture in the focus of a mirror is required to be taken.

The Impact of Educational and Gender Inequality on Income Inequality in South Asia

OpenAIRE

Kanwal, Ayesha; Munir, Kashif

2015-01-01

This paper examines the impact of educational and gender inequality in education on income inequality in South Asian countries for the time period of 1980 to 2010. Random effect model (REM) and fixed effect model (FEM) are used for estimation. Using the concept of education Gini the study find that there exist a positive relationship between educational and income inequality. The results also indicate that gender inequality in education at primary and tertiary level has positive and significa...

Deriving Einstein-Podolsky-Rosen steering inequalities from the few-body Abner Shimony inequalities

Science.gov (United States)

Zhou, Jie; Meng, Hui-Xian; Jiang, Shu-Han; Xu, Zhen-Peng; Ren, Changliang; Su, Hong-Yi; Chen, Jing-Ling

2018-04-01

For the Abner Shimony (AS) inequalities, the simplest unified forms of directions attaining the maximum quantum violation are investigated. Based on these directions, a family of Einstein-Podolsky-Rosen (EPR) steering inequalities is derived from the AS inequalities in a systematic manner. For these inequalities, the local hidden state (LHS) bounds are strictly less than the local hidden variable (LHV) bounds. This means that the EPR steering is a form of quantum nonlocality strictly weaker than Bell nonlocality.

Classical behavior of few-electron parabolic quantum dots

International Nuclear Information System (INIS)

Ciftja, O.

2009-01-01

Quantum dots are intricate and fascinating systems to study novel phenomena of great theoretical and practical interest because low dimensionality coupled with the interplay between strong correlations, quantum confinement and magnetic field creates unique conditions for emergence of fundamentally new physics. In this work we consider two-dimensional semiconductor quantum dot systems consisting of few interacting electrons confined in an isotropic parabolic potential. We study the many-electron quantum ground state properties of such systems in presence of a perpendicular magnetic field as the number of electrons is varied using exact numerical diagonalizations and other approaches. The results derived from the calculations of the quantum model are then compared to corresponding results for a classical model of parabolically confined point charges who interact with a Coulomb potential. We find that, for a wide range of parameters and magnetic fields considered in this work, the quantum ground state energy is very close to the classical energy of the most stable classical configuration under the condition that the classical energy is properly adjusted to incorporate the quantum zero point motion.

Looking for symmetric Bell inequalities

OpenAIRE

Bancal, Jean-Daniel; Gisin, Nicolas; Pironio, Stefano

2010-01-01

Finding all Bell inequalities for a given number of parties, measurement settings and measurement outcomes is in general a computationally hard task. We show that all Bell inequalities which are symmetric under the exchange of parties can be found by examining a symmetrized polytope which is simpler than the full Bell polytope. As an illustration of our method, we generate 238 885 new Bell inequalities and 1085 new Svetlichny inequalities. We find, in particular, facet inequalities for Bell e...

Absorber Alignment Measurement Tool for Solar Parabolic Trough Collectors: Preprint

Energy Technology Data Exchange (ETDEWEB)

Stynes, J. K.; Ihas, B.

2012-04-01

As we pursue efforts to lower the capital and installation costs of parabolic trough solar collectors, it is essential to maintain high optical performance. While there are many optical tools available to measure the reflector slope errors of parabolic trough solar collectors, there are few tools to measure the absorber alignment. A new method is presented here to measure the absorber alignment in two dimensions to within 0.5 cm. The absorber alignment is measured using a digital camera and four photogrammetric targets. Physical contact with the receiver absorber or glass is not necessary. The alignment of the absorber is measured along its full length so that sagging of the absorber can be quantified with this technique. The resulting absorber alignment measurement provides critical information required to accurately determine the intercept factor of a collector.

Iterated Crank-Nicolson method for hyperbolic and parabolic equations in numerical relativity

International Nuclear Information System (INIS)

Leiler, Gregor; Rezzolla, Luciano

2006-01-01

The iterated Crank-Nicolson is a predictor-corrector algorithm commonly used in numerical relativity for the solution of both hyperbolic and parabolic partial differential equations. We here extend the recent work on the stability of this scheme for hyperbolic equations by investigating the properties when the average between the predicted and corrected values is made with unequal weights and when the scheme is applied to a parabolic equation. We also propose a variant of the scheme in which the coefficients in the averages are swapped between two corrections leading to systematically larger amplification factors and to a smaller numerical dispersion

Automatic Fourier transform and self-Fourier beams due to parabolic potential

Energy Technology Data Exchange (ETDEWEB)

Zhang, Yiqi, E-mail: zhangyiqi@mail.xjtu.edu.cn [Key Laboratory for Physical Electronics and Devices of the Ministry of Education & Shaanxi Key Lab of Information Photonic Technique, Xi’an Jiaotong University, Xi’an 710049 (China); Liu, Xing [Key Laboratory for Physical Electronics and Devices of the Ministry of Education & Shaanxi Key Lab of Information Photonic Technique, Xi’an Jiaotong University, Xi’an 710049 (China); Belić, Milivoj R., E-mail: milivoj.belic@qatar.tamu.edu [Science Program, Texas A& M University at Qatar, P.O. Box 23874 Doha (Qatar); Zhong, Weiping [Department of Electronic and Information Engineering, Shunde Polytechnic, Shunde 528300 (China); Petrović, Milan S. [Institute of Physics, P.O. Box 68, 11001 Belgrade (Serbia); Zhang, Yanpeng, E-mail: ypzhang@mail.xjtu.edu.cn [Key Laboratory for Physical Electronics and Devices of the Ministry of Education & Shaanxi Key Lab of Information Photonic Technique, Xi’an Jiaotong University, Xi’an 710049 (China)

2015-12-15

We investigate the propagation of light beams including Hermite–Gauss, Bessel–Gauss and finite energy Airy beams in a linear medium with parabolic potential. Expectedly, the beams undergo oscillation during propagation, but quite unexpectedly they also perform automatic Fourier transform, that is, periodic change from the beam to its Fourier transform and back. In addition to oscillation, the finite-energy Airy beams exhibit periodic inversion during propagation. The oscillating period of parity-asymmetric beams is twice that of the parity-symmetric beams. Based on the propagation in parabolic potential, we introduce a class of optically-interesting beams that are self-Fourier beams—that is, the beams whose Fourier transforms are the beams themselves.

Health inequalities in Ethiopia: modeling inequalities in length of life within and between population groups.

Science.gov (United States)

Tranvåg, Eirik Joakim; Ali, Merima; Norheim, Ole Frithjof

2013-07-11

Most studies on health inequalities use average measures, but describing the distribution of health can also provide valuable knowledge. In this paper, we estimate and compare within-group and between-group inequalities in length of life for population groups in Ethiopia in 2000 and 2011. We used data from the 2011 and 2000 Ethiopia Demographic and Health Survey and the Global Burden of Disease study 2010, and the MODMATCH modified logit life table system developed by the World Health Organization to model mortality rates, life expectancy, and length of life for Ethiopian population groups stratified by wealth quintiles, gender and residence. We then estimated and compared within-group and between-group inequality in length of life using the Gini index and absolute length of life inequality. Length of life inequality has decreased and life expectancy has increased for all population groups between 2000 and 2011. Length of life inequality within wealth quintiles is about three times larger than the between-group inequality of 9 years. Total length of life inequality in Ethiopia was 27.6 years in 2011. Longevity has increased and the distribution of health in Ethiopia is more equal in 2011 than 2000, with length of life inequality reduced for all population groups. Still there is considerable potential for further improvement. In the Ethiopian context with a poor and highly rural population, inequality in length of life within wealth quintiles is considerably larger than between them. This suggests that other factors than wealth substantially contribute to total health inequality in Ethiopia and that identification and quantification of these factors will be important for identifying proper measures to further reduce length of life inequality.

Viscosity solutions of fully nonlinear functional parabolic PDE

Directory of Open Access Journals (Sweden)

Liu Wei-an

2005-01-01

Full Text Available By the technique of coupled solutions, the notion of viscosity solutions is extended to fully nonlinear retarded parabolic equations. Such equations involve many models arising from optimal control theory, economy and finance, biology, and so forth. The comparison principle is shown. Then the existence and uniqueness are established by the fixed point theory.

Almost periodic solutions to systems of parabolic equations

Directory of Open Access Journals (Sweden)

Janpou Nee

1994-01-01

Full Text Available In this paper we show that the second-order differential solution is 2-almost periodic, provided it is 2-bounded, and the growth of the components of a non-linear function of a system of parabolic equation is bounded by any pair of con-secutive eigenvalues of the associated Dirichlet boundary value problems.

Volume Inequalities for Isotropic Measures

OpenAIRE

Lutwak, Erwin; Yang, Deane; Zhang, Gaoyong

2006-01-01

A direct approach to Ball's simplex inequality is presented. This approach, which does not use the Brascamp-Lieb inequality, also gives Barthe's characterization of the simplex for Ball's inequality and extends it from discrete to arbitrary measures. It also yields the dual inequality, along with equality conditions, and it does both for arbitrary measures.

Optical analysis and performance evaluation of a solar parabolic dish concentrator

Directory of Open Access Journals (Sweden)

Pavlović Saša R.

2016-01-01

Full Text Available In this study, the optical design of a solar parabolic dish concentrator is presented. The parabolic dish concentrator consists from 11 curvilinear trapezoidal reflective petals made of polymethyl methacrylate with special reflective coating. The dish diameter is equal to 3.8 m and the theoretical focal point distance is 2.26 m. Numerical simulations are made with the commercial software TracePro from Lambda Research, USA, and the final optimum position between absorber and reflector was calculated to 2.075 m; lower than focus distance. This paper presents results for the optimum position and the optimum diameter of the receiver. The decision for selecting these parameters is based on the calculation of the total flux over the flat and corrugated pipe receiver surface; in its central region and in the peripheral region. The simulation results could be useful reference for designing and optimizing of solar parabolic dish concentrators as for as for CFD analysis, heat transfer and fluid flow analysis in corrugated spiral heat absorbers. [Projekat Ministarstva nauke Republike Srbije, br. III42006: Research and development of energy and environmentally highly effective polygeneration systems based on renewable energy resources i br. III45016: Fabrication and characterization of nanophotonic functional structures in biomedicine and informatics

The Geography of Gender Inequality.

Science.gov (United States)

Fisher, Brendan; Naidoo, Robin

2016-01-01

Reducing gender inequality is a major policy concern worldwide, and one of the Sustainable Development Goals. However, our understanding of the magnitude and spatial distribution of gender inequality results either from limited-scale case studies or from national-level statistics. Here, we produce the first high resolution map of gender inequality by analyzing over 689,000 households in 47 countries. Across these countries, we find that male-headed households have, on average, 13% more asset wealth and 303% more land for agriculture than do female-headed households. However, this aggregate global result masks a high degree of spatial heterogeneity, with bands of both high inequality and high equality apparent in countries and regions of the world. Further, areas where inequality is highest when measured by land ownership generally are not the same areas that have high inequality as measured by asset wealth. Our metrics of gender inequality in land and wealth are not strongly correlated with existing metrics of poverty, development, and income inequality, and therefore provide new information to increase the understanding of one critical dimension of poverty across the globe.

Immigration and income inequality

DEFF Research Database (Denmark)

Deding, Mette; Jakobsen, Vibeke; Azhar, Hussain

Four income inequality measures (Gini-coefficient, 90/10-decile ratio, and two generalized entropy indices) are applied to analyse immigrants’ income position relative to natives in a comparative perspective. Administrative data is used for Denmark, while survey data is used for Germany. We find...... higher inequality among immigrants than natives in Denmark, but vice versa for Germany. Over the period 1984-2003, this inequality gap has narrowed in both countries. At the same time, the contribution of immigrants to overall inequality has increased systematically, primarily caused by the increased...... share of immigrants in the population....

Global Inequalities in Youth Mortality, 2007-2012

Science.gov (United States)

Singh, Gopal K.; Lokhande, Anagha; Azuine, Romuladus E.

2015-01-01

Objectives: There is limited cross-national research on youth mortality. We examined age-and gender-variations in all-cause mortality among youth aged 15-34 years across 52 countries. Methods: Using the 2014 WHO mortality database, mortality rates for all countries were computed for the latest available year between 2007 and 2012. Rates, rate ratios, and ordinary least squares (OLS) and Poisson regression were used to analyze international variation in mortality. Results: Mortality rates among youth aged 15-34 years varied from a low of 28.4 deaths per 100,000 population for Hong Kong to a high of 250.6 for Russia and 619.1 for South Africa. For men aged 15-34, Singapore and Hong Kong had the lowest mortality rates (≈40 per 100,000), compared with South Africa and Russia with rates of 589.7 and 383.3, respectively. Global patterns in mortality among women were similar. Youth aged 15-24 in South Africa had 14 times higher mortality and those in the Philippines, Mexico, Russia, Colombia, and Brazil had 5-7 times higher mortality than those in Hong Kong. Youth aged 25-34 in Russia and South Africa had, respectively, 10 and 29 times higher mortality than their counterparts in Hong Kong. United States (US) had the 12th highest mortality rate among youth aged 15-24 and the 13th highest rate among youth aged 25-34. Overall, the US youth had 2-3 times higher rates of mortality than their counterparts in many industrialized countries including Hong Kong, Singapore, Netherlands, Switzerland, Germany, Norway, and Sweden. Income inequality, unemployment rate, and human development explained 50-66% of the global variance in youth mortality. Compared to the countries with low unemployment and income inequality and high human development levels, countries with high unemployment and income inequality and low human development had, respectively, 343%, 213%, and 205% higher risks of youth mortality. Conclusions and Global Health Implications: Marked international disparities in

Global Inequalities in Youth Mortality, 2007-2012

Directory of Open Access Journals (Sweden)

Gopal K. Singh, PhD

2015-03-01

Full Text Available Objectives: There is limited cross-national research on youth mortality. We examined age- and gender variations in all-cause mortality among youth aged 15-34 years across 52 countries. Methods: Using the 2014 WHO mortality database, mortality rates for all countries were computed for the latest available year between 2007 and 2012. Rates, rate ratios, and ordinary least squares (OLS and Poisson regression were used to analyze international variation in mortality. Results: Mortality rates among youth aged 15-34 years varied from a low of 28.4 deaths per 100,000 population for Hong Kong to a high of 250.6 for Russia and 619.1 for South Africa. For men aged 15-34, Singapore and Hong Kong had the lowest mortality rates (≈40 per 100,000, compared with South Africa and Russia with rates of 589.7 and 383.3, respectively. Global patterns in mortality among women were similar. Youth aged 15-24 in South Africa had 14 times higher mortality and those in the Philippines, Mexico, Russia, Colombia, and Brazil had 5-7 times higher mortality than those in Hong Kong. Youth aged 25-34 in Russia and South Africa had, respectively, 10 and 29 times higher mortality than their counterparts in Hong Kong. United States (US had the 12th highest mortality rate among youth aged 15-24 and the 13th highest rate among youth aged 25-34. Overall, the US youth had 2-3 times higher rates of mortality than their counterparts in many industrialized countries including Hong Kong, Singapore, Netherlands, Switzerland, Germany, Norway, and Sweden. Income inequality, unemployment rate, and human development explained 50-66% of the global variance in youth mortality. Compared to the countries with low unemployment and income inequality and high human development levels, countries with high unemployment and income inequality and low human development had, respectively, 343%, 213%, and 205% higher risks of youth mortality. Conclusions and Global Health Implications: Marked international

Seasonal Dynamics of Academic Achievement Inequality by Socioeconomic Status and Race/Ethnicity

Science.gov (United States)

Quinn, David M.; Cooc, North; McIntyre, Joe; Gomez, Celia J.

2016-01-01

Early studies examining seasonal variation in academic achievement inequality generally concluded that socioeconomic test score gaps grew more over the summer than the school year, suggesting schools served as "equalizers." In this study, we analyze seasonal trends in socioeconomic status (SES) and racial/ethnic test score gaps using…

Graphing Inequalities, Connecting Meaning

Science.gov (United States)

Switzer, J. Matt

2014-01-01

Students often have difficulty with graphing inequalities (see Filloy, Rojano, and Rubio 2002; Drijvers 2002), and J. Matt Switzer's students were no exception. Although students can produce graphs for simple inequalities, they often struggle when the format of the inequality is unfamiliar. Even when producing a correct graph of an…

The Growth-Inequality Association:

DEFF Research Database (Denmark)

Bjørnskov, Christian

2008-01-01

This note suggests that the association between income inequality and economic growth rates might arguably depend on the political ideology of incumbent governments. Estimates indicate that under leftwing governments, inequality is negatively associated with growth while the association is positive...... under rightwing governments. This may provide a qualification to recent studies of inequality....

Decomposing the Gini Inequality Index: An Expanded Solution with Survey Data Applied to Analyze Gender Income Inequality

Science.gov (United States)

Larraz, Beatriz

2015-01-01

The aim of this article is to propose a new breakdown of the Gini inequality ratio into three components ("within-group" inequality, "between-group" inequality, and intensity of "transvariation" between groups to the total inequality index). The between-group inequality concept computes all the differences in salaries…

A Concentrator Photovoltaic System Based on a Combination of Prism-Compound Parabolic Concentrators

Directory of Open Access Journals (Sweden)

Ngoc Hai Vu

2016-08-01

Full Text Available We present a cost-effective concentrating photovoltaic system composed of a prism and a compound parabolic concentrator (P-CPC. In this approach, the primary collector consists of a prism, a solid compound parabolic concentrator (CPC, and a slab waveguide. The prism, which is placed on the input aperture of CPC, directs the incoming sunlight beam to be parallel with the main axes of parabolic rims of CPC. Then, the sunlight is reflected at the parabolic rims and concentrated at the focal point of these parabolas. A slab waveguide is coupled at the output aperture of the CPC to collect focused sunlight beams and to guide them to the solar cell. The optical system was modeled and simulated with commercial ray tracing software (LightTools™. Simulation results show that the optical efficiency of a P-CPC can achieve up to 89%. when the concentration ratio of the P-CPC is fixed at 50. We also determine an optimal geometric structure of P-CPC based on simulation. Because of the simplicity of the P-CPC structure, a lower-cost mass production process is possible. A simulation based on optimal structure of P-CPC was performed and the results also shown that P-CPC has high angular tolerance for input sunlight. The high tolerance of the input angle of sunlight allows P-CPC solar concentrator utilize a single sun tracking system instead of a highly precise dual suntracking system as cost effective solution.

A comparison principle for an American option on several assets: Index and spread options

Directory of Open Access Journals (Sweden)

Peter Laurence

2003-07-01

Full Text Available Using the method of symmetrization, we compare the price of the American option on an index or spread to that of the solution of a parabolic variational inequality in one spatial variable. This comparison principle is established for a broad class of diffusion operators with time and state dependent coefficients. The purpose is to take a first step towards deriving symmmetrized problems whose solutions bound solutions of multidimensional American option problems with variable coefficients when the computation of the latter lies beyond the scope of the most powerful numerical methods.

On a strong solution of the non-stationary Navier-Stokes equations under slip or leak boundary conditions of friction type

Science.gov (United States)

Kashiwabara, Takahito

Strong solutions of the non-stationary Navier-Stokes equations under non-linearized slip or leak boundary conditions are investigated. We show that the problems are formulated by a variational inequality of parabolic type, to which uniqueness is established. Using Galerkin's method and deriving a priori estimates, we prove global and local existence for 2D and 3D slip problems respectively. For leak problems, under no-leak assumption at t=0 we prove local existence in 2D and 3D cases. Compatibility conditions for initial states play a significant role in the estimates.

Wide Area Detection and Identification of Underwater UXO Using Structural Acoustic Sensors

Science.gov (United States)

2011-07-08

acoustic holography NRL – Naval Research Laboratory PE – Parabolic Equation PML – Perfectly matched layer RVM – Relevance vector machines SA... variations , p(y|x)p(x) and q(y|x)q(x) cannot be 30 treated as identical; their difference must be taken into account when performing the estimation, in...CCy N aN i i a ia  (13) ai a i Niy ,2,1 ,0  (14) where the inequalities in Eq. (14) reflect the fact that, in order for xai to fit

The sociogeometry of inequality: Part I

Science.gov (United States)

Eliazar, Iddo

2015-05-01

The study of socioeconomic inequality is of prime economic and social importance, and the key quantitative gauges of socioeconomic inequality are Lorenz curves and inequality indices-the most notable of the latter being the popular Gini index. In this series of papers we present a sociogeometric framework to the study of socioeconomic inequality. In this part we shift from the notion of Lorenz curves to the notion of Lorenz sets, define inequality indices in terms of Lorenz sets, and introduce and explore a collection of distance-based and width-based inequality indices stemming from the geometry of Lorenz sets. In particular, three principle diameters of Lorenz sets are established as meaningful quantitative gauges of socioeconomic inequality-thus indeed providing a geometric quantification of socioeconomic inequality.

Income-related inequality in health and health care utilization in Chile, 2000-2009.

Science.gov (United States)

Vásquez, Felipe; Paraje, Guillermo; Estay, Manuel

2013-02-01

To measure and explain income-related inequalities in health and health care utilization in the period 2000 - 2009 in Chile, while assessing variations within the country and determinants of inequalities. Data from the National Socioeconomic Characterization Survey for 2000, 2003, and 2009 were used to measure inequality in health and health care utilization. Income-related inequality in health care utilization was assessed with standardized concentration indices for the probability and total number of visits to specialized care, generalized care, emergency care, dental care, mental health care, and hospital care. Self-assessed health status and physical limitations were used as proxies for health care need. Standardization was performed with demographic and need variables. The decomposition method was applied to estimate the contribution of each factor used to calculate the concentration index, including ethnicity, employment status, health insurance, and region of residence. In Chile, people in lower-income quintiles report worse health status and more physical limitations than people in higher quintiles. In terms of health service utilization, pro-rich inequities were found for specialized and dental visits with a slight pro-rich utilization for general practitioners and all physician visits. All pro-rich inequities have decreased over time. Emergency room visits and hospitalizations are concentrated among lower-income quintiles and have increased over time. Higher education and private health insurance contribute to a pro-rich inequity in dentist, general practitioner, specialized, and all physician visits. Income contributes to a pro-rich inequity in specialized and dentist visits, whereas urban residence and economic activity contribute to a pro-poor inequity in emergency room visits. The pattern of health care utilization in Chile is consistent with policies implemented in the country and in the intended direction. The significant income inequality in the

On quadratic variation of martingales

Indian Academy of Sciences (India)

On quadratic variation of martingales. 459. The proof relied on the theory of stochastic integration. Subsequently, in Karandikar. [4], the formula was derived using only Doob's maximal inequality. Thus this could be the starting point for the development of stochastic calculus for continuous semimartingales without bringing in ...

Handbook of functional equations functional inequalities

CERN Document Server

2014-01-01

As Richard Bellman has so elegantly stated at the Second International Conference on General Inequalities (Oberwolfach, 1978), “There are three reasons for the study of inequalities: practical, theoretical, and aesthetic.” On the aesthetic aspects, he said, “As has been pointed out, beauty is in the eye of the beholder. However, it is generally agreed that certain pieces of music, art, or mathematics are beautiful. There is an elegance to inequalities that makes them very attractive.” The content of the Handbook focuses mainly on both old and recent developments on approximate homomorphisms, on a relation between the Hardy–Hilbert and the Gabriel inequality, generalized Hardy–Hilbert type inequalities on multiple weighted Orlicz spaces, half-discrete Hilbert-type inequalities, on affine mappings, on contractive operators, on multiplicative Ostrowski and trapezoid inequalities, Ostrowski type inequalities for the  Riemann–Stieltjes integral, means and related functional inequalities, Weighted G...

An inverse problem in a parabolic equation

Directory of Open Access Journals (Sweden)

Zhilin Li

1998-11-01

Full Text Available In this paper, an inverse problem in a parabolic equation is studied. An unknown function in the equation is related to two integral equations in terms of heat kernel. One of the integral equations is well-posed while another is ill-posed. A regularization approach for constructing an approximate solution to the ill-posed integral equation is proposed. Theoretical analysis and numerical experiment are provided to support the method.

Firming Up Inequality

OpenAIRE

Jae Song; David J. Price; Fatih Guvenen; Nicholas Bloom; Till von Wachter

2015-01-01

Earnings inequality in the United States has increased rapidly over the last three decades, but little is known about the role of firms in this trend. For example, how much of the rise in earnings inequality can be attributed to rising dispersion between firms in the average wages they pay, and how much is due to rising wage dispersion among workers within firms? Similarly, how did rising inequality affect the wage earnings of different types of workers working for the same employer—men vs. w...

Baby Booming Inequality? Demographic Change and Inequality in Norway, 1967{2004.

OpenAIRE

Almås, Ingvild; Havnes, Tarjei; Mogstad, Magne

2011-01-01

We demonstrate how age-adjusted inequality measures can be used to evaluate whether changes in inequality over time are because of changes in the age structure. In particular, we explore the hypothesis that the substantial rise in earnings inequality since the early 1980s is driven by the large baby boom cohorts approaching the peak of the age-earnings profile. Using administrative data on earnings for every Norwegian male over the period 1967-2004, we find that the impact of age ...

Inequalities in lung cancer mortality by the educational level in 10 European populations

NARCIS (Netherlands)

Mackenbach, Johan P.; Huisman, Martijn; Andersen, Otto; Bopp, Matthias; Borgan, Jens-Kristian; Borrell, Carme; Costa, Giuseppe; Deboosere, Patrick; Donkin, Angela; Gadeyne, Sylvie; Minder, Christoph; Regidor, Enrique; Spadea, Teresa; Valkonen, Tapani; Kunst, Anton E.

2004-01-01

Previous studies have shown that due to differences in the progression of the smoking epidemic European countries differ in the direction and size of socioeconomic variations in smoking prevalence. We studied differences in the direction and size of inequalities in lung cancer mortality by the

Stability in terms of two measures for a class of semilinear impulsive parabolic equations

International Nuclear Information System (INIS)

Dvirnyj, Aleksandr I; Slyn'ko, Vitalij I

2013-01-01

The problem of stability in terms of two measures is considered for semilinear impulsive parabolic equations. A new version of the comparison method is proposed, and sufficient conditions for stability in terms of two measures are obtained on this basis. An example of a hybrid impulsive system formed by a system of ordinary differential equations coupled with a partial differential equation of parabolic type is given. The efficiency of the described approaches is demonstrated. Bibliography: 24 titles.

Bilinear reduced order approximate model of parabolic distributed solar collectors

KAUST Repository

Elmetennani, Shahrazed; Laleg-Kirati, Taous-Meriem

2015-01-01

This paper proposes a novel, low dimensional and accurate approximate model for the distributed parabolic solar collector, by means of a modified gaussian interpolation along the spatial domain. The proposed reduced model, taking the form of a low

Solar parabolic dish Stirling engine system design, simulation, and thermal analysis

International Nuclear Information System (INIS)

Hafez, A.Z.; Soliman, Ahmed; El-Metwally, K.A.; Ismail, I.M.

2016-01-01

Highlights: • Modeling and simulation for different parabolic dish Stirling engine designs using Matlab®. • The effect of solar dish design features and factors had been taken. • Estimation of output power from the solar dish using Matlab®. • The present analysis provides a theoretical guidance for designing and operating solar parabolic dish system. - Abstract: Modeling and simulation for different parabolic dish Stirling engine designs have been carried out using Matlab®. The effect of solar dish design features and factors such as material of the reflector concentrators, the shape of the reflector concentrators and the receiver, solar radiation at the concentrator, diameter of the parabolic dish concentrator, sizing the aperture area of concentrator, focal Length of the parabolic dish, the focal point diameter, sizing the aperture area of receiver, geometric concentration ratio, and rim angle have been studied. The study provides a theoretical guidance for designing and operating solar parabolic dish Stirling engines system. At Zewail city of Science and Technology, Egypt, for a 10 kW Stirling engine; The maximum solar dish Stirling engine output power estimation is 9707 W at 12:00 PM where the maximum beam solar radiation applied in solar dish concentrator is 990 W/m"2 at 12:00 PM. The performance of engine can be improved by increasing the precision of the engine parts and the heat source efficiency. The engine performance could be further increased if a better receiver working fluid is used. We can conclude that where the best time for heating the fluid and fasting the processing, the time required to heat the receiver to reach the minimum temperature for operating the Solar-powered Stirling engine for different heat transfer fluids; this will lead to more economic solar dish systems. Power output of the solar dish system is one of the most important targets in the design that show effectiveness of the system, and this has achieved when we take

A parabolic singular perturbation problem with an internal layer

NARCIS (Netherlands)

Grasman, J.; Shih, S.D.

2004-01-01

A method is presented to approximate with singular perturbation methods a parabolic differential equation for the quarter plane with a discontinuity at the corner. This discontinuity gives rise to an internal layer. It is necessary to match the local solution in this layer with the one in a corner

Globalization and inequality

NARCIS (Netherlands)

Mills, Melinda

Globalization is increasingly linked to inequality, but with often divergent and polarized findings. Some researchers show that globalization accentuates inequality both within and between countries. Others maintain that these claims are patently incorrect, arguing that globalization has

Globalization, Inequality & International Economic Law

Directory of Open Access Journals (Sweden)

Frank J. Garcia

2017-04-01

Full Text Available International law in general, and international economic law in particular, to the extent that either has focused on the issue of inequality, has done so in terms of inequality between states. Largely overlooked has been the topic of inequality within states and how international law has influenced that reality. From the perspective of international economic law, the inequality issue is closely entwined with the topics of colonialism and post-colonialism, the proper meaning of development, and globalization. While international economic law has undoubtedly contributed to the rise of inequality, it is now vital that the subject of international economic law be examined for how it may contribute to the lessening of inequality. To do so will require a shift in the way that we think, in order to address inequality as a problem of an emerging global market society, and how best to regulate that society and its institutions.

Strain effect on graphene nanoribbon carrier statistic in the presence of non-parabolic band structure

International Nuclear Information System (INIS)

Izuani Che Rosid, N A; Ahmadi, M T; Ismail, Razali

2016-01-01

The effect of tensile uniaxial strain on the non-parabolic electronic band structure of armchair graphene nanoribbon (AGNR) is investigated. In addition, the density of states and the carrier statistic based on the tight-binding Hamiltonian are modeled analytically. It is found that the property of AGNR in the non-parabolic band region is varied by the strain. The tunable energy band gap in AGNR upon strain at the minimum energy is described for each of n-AGNR families in the non-parabolic approximation. The behavior of AGNR in the presence of strain is attributed to the breakable AGNR electronic band structure, which varies the physical properties from its normality. The linear relation between the energy gap and the electrical properties is featured to further explain the characteristic of the deformed AGNR upon strain. (paper)

ε-neighbourhoods of orbits of parabolic diffeomorphisms and cohomological equations

International Nuclear Information System (INIS)

Resman, Maja

2014-01-01

In this article, we study the analyticity of (directed) areas of ε-neighbourhoods of orbits of parabolic germs. The article is motivated by the question of analytic classification using ε-neighbourhoods of orbits in the simplest formal class. We show that the coefficient in front of the ε 2 term in the asymptotic expansion in ε, which we call the principal part of the area, is a sectorially analytic function in the initial point of the orbit. It satisfies a cohomological equation similar to the standard trivialization equation for parabolic diffeomorphisms. We give necessary and sufficient conditions on a diffeomorphism f for the existence of a globally analytic solution of this equation. Furthermore, we introduce a new classification type for diffeomorphisms implied by this new equation and investigate the relative position of its classes with respect to the analytic classes. (paper)

Achieving uniform efficient illumination with multiple asymmetric compound parabolic luminaires

Science.gov (United States)

Gordon, Jeffrey M.; Kashin, Peter

1994-01-01

Luminaire designs based on multiple asymmetric nonimaging compound parabolic reflectors are proposed for 2-D illumination applications that require highly uniform far-field illuminance, while ensuring maximal lighting efficiency and sharp angular cutoffs. The new designs derive from recent advances in nonimaging secondary concentrators for line-focus solar collectors. The light source is not treated as a single entity, but rather is divided into two or more separate adjoining sources. An asymmetric compound parabolic luminaire is then designed around each half-source. Attaining sharp cutoffs requires relatively large reflectors. However, severe truncation of the reflectors renders these devices as compact as many conventional luminaires, at the penalty of a small fraction of the radiation being emitted outside the nominal cutoff. The configurations that maximize the uniformity of far-field illuminance offer significant improvements in flux homogeneity relative to alternative designs to date.

Influence of an anisotropic parabolic potential on the quantum dot qubit

International Nuclear Information System (INIS)

Zhao Cuilan; Cai Chunyu; Xiao Jingling

2013-01-01

To study the influence of an anisotropic parabolic potential (APP) on the properties of a quantum dot (QD) qubit, we obtain the eigenenergies and eigenfunctions of the ground and first excited state of an electron, which is strongly coupled to the bulk longitudinal optical (LO) phonons, in a QD under the influence of an APP by the celebrated Lee—Low—Pines (LLP) unitary transformation and the Pekar type variational (PTV) methods. Then, this kind of two-level quantum system can be excogitated to constitute a single qubit. When the electron locates at the superposition state of its related eigenfunctions, we get the time evolution of the electron's probability density. Finally, the influence of an APP on the QD qubit is investigated. The numerical calculations indicate that the probability density will oscillate periodically and it is a decreasing function of the effective confinement lengths of the APP in different directions. Whereas its oscillatory period is an increasing one and will diminish with enhancing the electron—phonon (EP) coupling strength. (semiconductor physics)

The Geography of Gender Inequality.

Directory of Open Access Journals (Sweden)

Brendan Fisher

Full Text Available Reducing gender inequality is a major policy concern worldwide, and one of the Sustainable Development Goals. However, our understanding of the magnitude and spatial distribution of gender inequality results either from limited-scale case studies or from national-level statistics. Here, we produce the first high resolution map of gender inequality by analyzing over 689,000 households in 47 countries. Across these countries, we find that male-headed households have, on average, 13% more asset wealth and 303% more land for agriculture than do female-headed households. However, this aggregate global result masks a high degree of spatial heterogeneity, with bands of both high inequality and high equality apparent in countries and regions of the world. Further, areas where inequality is highest when measured by land ownership generally are not the same areas that have high inequality as measured by asset wealth. Our metrics of gender inequality in land and wealth are not strongly correlated with existing metrics of poverty, development, and income inequality, and therefore provide new information to increase the understanding of one critical dimension of poverty across the globe.

Global interpersonal inequality: Trends and measurement

DEFF Research Database (Denmark)

Niño-Zarazúa, Miguel; Roope, Laurence; Tarp, Finn

This paper discusses different approaches to the measurement of global interpersonal in equality. Trends in global interpersonal inequality during 1975-2005 are measured using data from UNU-WIDER’s World Income Inequality Database. In order to better understand the trends, global interpersonal...... inequality is decomposed into within-country and between-country inequality. The paper illustrates that the relationship between global interpersonal inequality and these constituent components is a complex one. In particular, we demonstrate that the changes in China’s and India’s income distributions over...... the past 30 years have simultaneously caused inequality to rise domestically in those countries, while tending to reduce global inter-personal inequality. In light of these findings, we reflect on the meaning and policy relevance of global vis-à-vis domestic inequality measures...

Fixed point theory, variational analysis, and optimization

CERN Document Server

Al-Mezel, Saleh Abdullah R; Ansari, Qamrul Hasan

2015-01-01

""There is a real need for this book. It is useful for people who work in areas of nonlinear analysis, optimization theory, variational inequalities, and mathematical economics.""-Nan-Jing Huang, Sichuan University, Chengdu, People's Republic of China

Global Inequalities in Cervical Cancer Incidence and Mortality are Linked to Deprivation, Low Socioeconomic Status, and Human Development

OpenAIRE

Gopal K. Singh, PhD; Romuladus E. Azuine, DrPH, RN; Mohammad Siahpush, PhD

2012-01-01

Objectives This study examined global inequalities in cervical cancer incidence and mortality rates as a function of cross-national variations in the Human Development Index (HDI), socioeconomic factors, Gender Inequality Index (GII), and healthcare expenditure. Methods Age-adjusted incidence and mortality rates were calculated for women in 184 countries using the 2008 GLOBOCAN database, and incidence and mortality trends were analyzed using the WHO cancer mortality database. Log-linear regre...

(Mis)perceptions of inequality.

Science.gov (United States)

Hauser, Oliver P; Norton, Michael I

2017-12-01

Laypeople's beliefs about the current distribution of outcomes such as income and wealth in their country influence their attitudes toward issues ranging from taxation to healthcare - but how accurate are these beliefs? We review the burgeoning literature on (mis)perceptions of inequality. First, we show that people on average misperceive current levels of inequality, typically underestimating the extent of inequality in their country. Second, we delineate potential causes of these misperceptions, including people's overreliance on cues from their local environment, leading to their erroneous beliefs about both the overall distributions of wealth and income and their place in those distributions. Third, we document that these (mis)perceptions of inequality - but not actual levels of inequality - drive behavior and preferences for redistribution. More promisingly, we review research suggesting that correcting misperceptions influences preferences and policy outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Wringing out better Bell inequalities

International Nuclear Information System (INIS)

Braunstein, S.L.; Caves, C.M.

1989-01-01

Local realism implies constraints on the statistics of two physically separated systems. These constraints, known collectively as Bell inequalities, can be violated by quantum mechanics. We generalize the standard Bell inequalities in two ways: first, by 'chaining' the Clauser-Horne-Shimony-Holt Bell inequality for two-state systems and, second, by formulating information-theoretic Bell inequalities that apply to any pair of systems. (orig.)

Conditional stability in determination of initial data for stochastic parabolic equations

International Nuclear Information System (INIS)

Yuan, Ganghua

2017-01-01

In this paper, we solve two kinds of inverse problems in determination of the initial data for stochastic parabolic equations. One is determination of the initial data by lateral boundary observation on arbitrary portion of the boundary, the second one is determination of the initial data by internal observation in a subregion inside the domain. We obtain conditional stability for the two kinds of inverse problems. To prove the results, we estimate the initial data by a terminal observation near the initial time, then we estimate this terminal observation by lateral boundary observation on arbitrary portion of the boundary or internal observation in a subregion inside the domain. To achieve those goals, we derive several new Carleman estimates for stochastic parabolic equations in this paper. (paper)

Conditional stability in determination of initial data for stochastic parabolic equations

Science.gov (United States)

Yuan, Ganghua

2017-03-01

In this paper, we solve two kinds of inverse problems in determination of the initial data for stochastic parabolic equations. One is determination of the initial data by lateral boundary observation on arbitrary portion of the boundary, the second one is determination of the initial data by internal observation in a subregion inside the domain. We obtain conditional stability for the two kinds of inverse problems. To prove the results, we estimate the initial data by a terminal observation near the initial time, then we estimate this terminal observation by lateral boundary observation on arbitrary portion of the boundary or internal observation in a subregion inside the domain. To achieve those goals, we derive several new Carleman estimates for stochastic parabolic equations in this paper.

Looking for symmetric Bell inequalities

Energy Technology Data Exchange (ETDEWEB)

Bancal, Jean-Daniel; Gisin, Nicolas [Group of Applied Physics, University of Geneva, 20 rue de l' Ecole-de Medecine, CH-1211 Geneva 4 (Switzerland); Pironio, Stefano, E-mail: jean-daniel.bancal@unige.c [Laboratoire d' Information Quantique, Universite Libre de Bruxelles (Belgium)

2010-09-24

Finding all Bell inequalities for a given number of parties, measurement settings and measurement outcomes is in general a computationally hard task. We show that all Bell inequalities which are symmetric under the exchange of parties can be found by examining a symmetrized polytope which is simpler than the full Bell polytope. As an illustration of our method, we generate 238 885 new Bell inequalities and 1085 new Svetlichny inequalities. We find, in particular, facet inequalities for Bell experiments involving two parties and two measurement settings that are not of the Collins-Gisin-Linden-Massar-Popescu type.

Looking for symmetric Bell inequalities

International Nuclear Information System (INIS)

Bancal, Jean-Daniel; Gisin, Nicolas; Pironio, Stefano

2010-01-01

Finding all Bell inequalities for a given number of parties, measurement settings and measurement outcomes is in general a computationally hard task. We show that all Bell inequalities which are symmetric under the exchange of parties can be found by examining a symmetrized polytope which is simpler than the full Bell polytope. As an illustration of our method, we generate 238 885 new Bell inequalities and 1085 new Svetlichny inequalities. We find, in particular, facet inequalities for Bell experiments involving two parties and two measurement settings that are not of the Collins-Gisin-Linden-Massar-Popescu type.

Health inequality - determinants and policies

DEFF Research Database (Denmark)

Diderichsen, Finn; Andersen, Ingelise; Manual, Celie

2012-01-01

The review ”Health inequality – determinants and policies” identifies key-areas to be addressed with the aim to reduce the social inequality in health. The general life expectancy has steadily been increasing, but the data reveals marked social inequalities in health as well as life expectancy....... The review seeks to identify the causes of this social inequality. The analysis finds 12 areas of great importance for the inequality in health. This is i.e. early child development, schooling and education, the health behavior of the population, and the role of the health system. Within each of the 12 areas...

Non-commutative Nash inequalities

International Nuclear Information System (INIS)

Kastoryano, Michael; Temme, Kristan

2016-01-01

A set of functional inequalities—called Nash inequalities—are introduced and analyzed in the context of quantum Markov process mixing. The basic theory of Nash inequalities is extended to the setting of non-commutative L p spaces, where their relationship to Poincaré and log-Sobolev inequalities is fleshed out. We prove Nash inequalities for a number of unital reversible semigroups

Parabolic cyclinder functions : examples of error bounds for asymptotic expansions

NARCIS (Netherlands)

R. Vidunas; N.M. Temme (Nico)

2002-01-01

textabstractSeveral asymptotic expansions of parabolic cylinder functions are discussedand error bounds for remainders in the expansions are presented. Inparticular Poincaré-type expansions for large values of the argument$z$ and uniform expansions for large values of the parameter areconsidered.

Social inequality: philosophical and sociological reflection

Directory of Open Access Journals (Sweden)

A. Sh. Victorov

2014-01-01

Full Text Available Social inequality is the phenomena that is hypothetically the base for first human communities genesis. Modern model for capitalist society as market relations form fails to satisfy the needs of society’s social development, and strongly requires to create new social knowledge structure and new approach for inequality sociology theory development. Our study conceptual logic comprises routine, philosophic and ideological reflexions analysis to create new social inequality definition in the context of new sociologic knowledge structure. Social inequality is the one of key problems in global sociology; the need is obvious to extract social inequality into separate discipline. Inequality sociology target is the decision of theoretical and practical problems in the formation of comprehensive knowledge about inequality phenomena in modern community, and in the development of common and specialized theoretical-methodological base for inequality study.

Where do inmmigrants fare worse? Modeling workplace wage gap variation with longitudinal employer-employee data.

Science.gov (United States)

Tomaskovic-Devey, Donald; Hällsten, Martin; Avent-Holt, Dustin

2015-01-01

The authors propose a strategy for observing and explaining workplace variance in categorically linked inequalities. Using Swedish economy-wide linked employer-employee panel data, the authors examine variation in workplace wage inequalities between native Swedes and non-Western immigrants. Consistent with relational inequality theory, the authors' findings are that immigrant-native wage gaps vary dramatically across workplaces, even net of strong human capital controls. The authors also find that, net of observed and fixed-effect controls for individual traits, workplace immigrant-native wage gaps decline with increased workplace immigrant employment and managerial representation and increase when job segregation rises. These results are stronger in high-inequality workplaces and for white-collar employees: contexts in which one expects status-based claims on organizational resources, the central causal mechanism identified by relational inequality theory, to be stronger. The authors conclude that workplace variation in the non-Western immigrant-native wage gaps is contingent on organizational variationin the relative power of groups and the institutional context in which that power is exercised.

EXERGY AND CARBON CREDITS FOR SERIES CONNECTED N PHOTOVOLTAIC THERMAL - COMPOUND PARABOLIC CONCENTRATOR (PVT-CPC) COLLECTOR: AT CONSTANT OUTLET TEMPERATURE

OpenAIRE

Rohit Tripathi 1,*, G. N. Tiwari 2

2017-01-01

In the present study, overall energy and exergy performance of partially covered N photovoltaic thermal - compound parabolic concentrators (PVT-CPC) (25% covered by glass to glass PV module) collector connected in series have been carried out at constant outlet temperature mode. Further, comparison in performance for partially covered N photovoltaic thermal - compound parabolic concentrators (PVT-CPC) [case (i)] and N compound parabolic concentrators (CPC) collector [case (ii)] connected in s...

Quantum mechanics and Bell's inequalities

International Nuclear Information System (INIS)

Jones, R.T.; Adelberger, E.G.

1994-01-01

Santos argues that, if one interprets probabilities as ratios of detected events to copies of the physical system initially prepared, the quantum mechanical predictions for the classic tests of Bell's inequalities do not violate the inequalities. Furthermore, he suggests that quantum mechanical states which do violate the inequalities are not physically realizable. We discuss a physically realizable experiment, meeting his requirements, where quantum mechanics does violate the inequalities

Exergy Analysis of a Pilot Parabolic Solar Dish-Stirling System

Directory of Open Access Journals (Sweden)

Ehsan Gholamalizadeh

2017-09-01

Full Text Available Energy and exergy analyses were carried out for a pilot parabolic solar dish-Stirling System. The system was set up at a site at Kerman City, located in a sunny desert area of Iran. Variations in energy and exergy efficiency were considered during the daytime hours of the average day of each month in a year. A maximum collector energy efficiency and total energy efficiency of 54% and 12.2%, respectively, were predicted in July, while during the period between November and February the efficiency values were extremely low. The maximum collector exergy efficiency was 41.5% in July, while the maximum total exergy efficiency reached 13.2%. The values of energy losses as a percentage of the total losses of the main parts of the system were also reported. Results showed that the major energy and exergy losses occurred in the receiver. The second biggest portion of energy losses occurred in the Stirling engine, while the portion of exergy loss in the concentrator was higher compared to the Stirling engine. Finally, the performance of the Kerman pilot was compared to that of the EuroDish project.

Neighbourhood variation and inequity of primary health service use by mothers from London-Middlesex, Ontario.

Science.gov (United States)

Holtz, Catherine; Gilliland, Jason; Thind, Amardeep; Wilk, Piotr; Campbell, M Karen

2014-01-01

Primary health service use (P-HSU) may be influenced by contextual characteristics and is equitable when driven by need. Contextual effects and inequity of maternal P-HSU were determined. Participant data from a London-Middlesex, Ontario, prenatal cohort were linked by residential address to contextual characteristics. Multilevel logistic regression estimated contextual effects and tested for effect measure modification of need factors. Maternal P-HSU varied between neighbourhoods. The effect of obesity was different for rural mothers living in low- (OR = 0.26) and middle-income households (OR = 0.15) and for urban mothers living in high-income households (OR = 2.82). The effect of having a health condition was greatest in mothers with three or more children (OR = 2.41). Differences in maternal P-HSU exist between neighbourhoods, and enabling factors modified need factors' effects, identifying subgroups of mothers with inequitable P-HSU. RESULTS have the potential to inform Canadian health policy with regard to contextual effects and inequity of P-HSU.

Data assimilation with inequality constraints

Science.gov (United States)

Thacker, W. C.

If values of variables in a numerical model are limited to specified ranges, these restrictions should be enforced when data are assimilated. The simplest option is to assimilate without regard for constraints and then to correct any violations without worrying about additional corrections implied by correlated errors. This paper addresses the incorporation of inequality constraints into the standard variational framework of optimal interpolation with emphasis on our limited knowledge of the underlying probability distributions. Simple examples involving only two or three variables are used to illustrate graphically how active constraints can be treated as error-free data when background errors obey a truncated multi-normal distribution. Using Lagrange multipliers, the formalism is expanded to encompass the active constraints. Two algorithms are presented, both relying on a solution ignoring the inequality constraints to discover violations to be enforced. While explicitly enforcing a subset can, via correlations, correct the others, pragmatism based on our poor knowledge of the underlying probability distributions suggests the expedient of enforcing them all explicitly to avoid the computationally expensive task of determining the minimum active set. If additional violations are encountered with these solutions, the process can be repeated. Simple examples are used to illustrate the algorithms and to examine the nature of the corrections implied by correlated errors.

The Oxford handbook of economic inequality

NARCIS (Netherlands)

Salverda, W.; Nolan, B.; Smeeding, T.M.

2009-01-01

The essential guide for students and researchers interested in economic inequality Contains 27 original research contributions from the top names in economic inequality. The Oxford Handbook of Economic Inequality presents a new and challenging analysis of economic inequality, focusing primarily on

Cyclotron heating rate in a parabolic mirror

International Nuclear Information System (INIS)

Smith, P.K.

1984-01-01

Cyclotron resonance heating rates are found for a parabolic magnetic mirror. The equation of motion for perpendicular velocity is solved, including the radial magnetic field terms neglected in earlier papers. The expression for heating rate involves an infinite series of Anger's and Weber's functions, compared with a single term of the unrevised expression. The new results show an increase of heating rate compared with previous results. A simple expression is given for the ratio of the heating rates. (author)

Investigation on the dynamic behaviour of a parabolic trough power plant during strongly cloudy days

International Nuclear Information System (INIS)

Al-Maliki, Wisam Abed Kattea; Alobaid, Falah; Starkloff, Ralf; Kez, Vitali; Epple, Bernd

2016-01-01

Highlights: • A detailed dynamic model of a parabolic trough solar thermal power plant is done. • Simulated results are compared to the experimental data from the real power plant. • Discrepancy between model result and real data is caused by operation strategy. • The model strategy increased the operating hours of power plant by around 2.5–3 h. - Abstract: The objective of this study is the development of a full scale dynamic model of a parabolic trough power plant with a thermal storage system, operated by the Actividades de Construcción y Servicios Group in Spain. The model includes solar field, thermal storage system and the power block and describes the heat transfer fluid and steam/water paths in detail. The parabolic trough power plant is modelled using Advanced Process Simulation Software (APROS). To validate the model, the numerical results are compared to the measured data, obtained from “Andasol II” during strongly cloudy periods in the summer days. The comparisons show a qualitative agreement between the dynamic simulation model and the measurements. The results confirm that the thermal storage enables the parabolic trough power plant to provide a constant power rate when the storage energy discharge is available, despite significant oscillations in the solar radiation.

Socioeconomic differences in emotional symptoms among adolescents in the Nordic countries: recommendations on how to present inequality.

Science.gov (United States)

Nielsen, Line; Damsgaard, Mogens Trab; Meilstrup, Charlotte; Due, Pernille; Madsen, Katrine Rich; Koushede, Vibeke; Holstein, Bjørn Evald

2015-02-01

This comparative study examines absolute and relative socioeconomic differences in emotional symptoms among adolescents using standardised data from five Nordic countries and gives recommendations on how to present socioeconomic inequality. The Health Behaviour in School-aged Children (HBSC) international cross-sectional study from 2005/2006 provided data on 29,642 11-15-year-old adolescents from nationally random samples in Denmark, Finland, Iceland, Norway and Sweden. The outcome was daily emotional symptoms. Family Affluence Scale (FAS) was used as indicator of socioeconomic position. We applied four summary measures of inequality: Prevalence Difference, Odds Ratio, Slope Index of Inequality and Relative Index of Inequality, and presented the socioeconomic inequality by a graphical illustration of the prevalence of emotional symptoms, the size of the FAS groups and the summary indices of inequality in each country. The prevalence of emotional symptoms ranged from 8.1% in Denmark to 13.2% in Iceland. There were large country variations in the size of the low FAS-group ranging from 2% in Iceland to 12% in Finland. The largest absolute and relative socioeconomic inequalities were found in Iceland and the smallest in Finland for girls and in Denmark for boys. Emotional symptoms were more common among nordic adolescents from low affluence families this association appeared in the study of both absolute and relative inequality. A comprehensive presentation of socioeconomic inequality should include the prevalence of the health outcome, the size of the socioeconomic groups, and the regression line representing the summary indices of inequality. © 2014 the Nordic Societies of Public Health.

Income-related inequality and inequity in the use of dental services in Finland after a major subsidization reform.

Science.gov (United States)

Raittio, Eero; Kiiskinen, Urpo; Helminen, Sari; Aromaa, Arpo; Suominen, Anna Liisa

2015-06-01

In Finland, a major oral healthcare reform (OHCR), implemented during 2001-2002, opened the public dental services (PDS) and extended subsidies for private dental services to entire adult population. Before the reform, adults born earlier than 1956 were not entitled to use PDS nor did they receive any reimbursements for their private dental costs. We aimed to examine changes in the income-related inequality and inequity in the use of dental services among the adult Finns after the reform. Representative data from Finnish adults born in 1970 or earlier were gathered from three identical postal surveys concerning the use of dental services and subjective perceptions of oral health. Those surveys were conducted before the OHCR in 2001 (n = 1907) and after the OHCR in 2004 (n = 1629) and 2007 (n = 1509). We used concentration index and its decomposition to analyse income-related inequality and inequity in the use of dental services and factors associated with them. Results showed that pro-rich inequality and inequity in the overall use of dental services narrowed from 2001 to 2004. However, between 2004 and 2007, pro-rich inequality and inequity widened, so it returned to a rather similar level in 2007 as it had been in 2001. Most of the pro-rich inequality and inequity were related to regular dental visiting habit and income level. While there was pro-poor inequality and inequity in the use of PDS, there was pro-rich inequality and inequity in the use of private dental services throughout the study years. It seems that income-related inequality and inequity in the use of dental services narrowed only temporarily after the reform. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Extending the Utility of the Parabolic Approximation in Medical Ultrasound Using Wide-Angle Diffraction Modeling.

Science.gov (United States)

Soneson, Joshua E

2017-04-01

Wide-angle parabolic models are commonly used in geophysics and underwater acoustics but have seen little application in medical ultrasound. Here, a wide-angle model for continuous-wave high-intensity ultrasound beams is derived, which approximates the diffraction process more accurately than the commonly used Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation without increasing implementation complexity or computing time. A method for preventing the high spatial frequencies often present in source boundary conditions from corrupting the solution is presented. Simulations of shallowly focused axisymmetric beams using both the wide-angle and standard parabolic models are compared to assess the accuracy with which they model diffraction effects. The wide-angle model proposed here offers improved focusing accuracy and less error throughout the computational domain than the standard parabolic model, offering a facile method for extending the utility of existing KZK codes.

Functional Bell inequalities can serve as a stronger entanglement witness than conventional Bell inequalities

International Nuclear Information System (INIS)

Sen, Aditi; Sen, Ujjwal; Zukowski, Marek

2002-01-01

We consider a Bell inequality for a continuous range of settings of the apparatus at each site. This 'functional' Bell inequality gives a better range of violation for generalized Greenberger, Horne, and Zeilinger states. Also a family of N-qubit bound entangled states violate this inequality for N>5

Dynamic Changes in Determinants of Inequalities in Health in Europe with Focus on Retired – with particular Regard to Retired Danes

DEFF Research Database (Denmark)

Christiansen, Terkel; Lauridsen, Jørgen Trankjær

Earlier studies of health inequality across European countries have shown intriguing results, in particular with respect to retirement status as one of the determinants of health inequality. A priori, one would expect that inequality in health and income would be associated. Theory suggests...... into its determinants allows a calculation of the contribution of each determinant’s separate contribution to inequality in health. The results presented here indicate that retirement status contributes substantially to income-related inequality in health across European countries, and that the variation...... can be explained by income differences as well as health differences, depending on the country considered. Furthermore, it is indicated that the contribution from retirement status falls for certain countries due to improved socioeconomic status as well as improved health of the retired....

L^p-continuity of solutions to parabolic free boundary problems

Directory of Open Access Journals (Sweden)

Abdeslem Lyaghfouri

2015-07-01

Full Text Available In this article, we consider a class of parabolic free boundary problems. We establish some properties of the solutions, including L^infinity-regularity in time and a monotonicity property, from which we deduce strong L^p-continuity in time.

Interior Gradient Estimates for Nonuniformly Parabolic Equations II

Directory of Open Access Journals (Sweden)

Lieberman Gary M

2007-01-01

Full Text Available We prove interior gradient estimates for a large class of parabolic equations in divergence form. Using some simple ideas, we prove these estimates for several types of equations that are not amenable to previous methods. In particular, we have no restrictions on the maximum eigenvalue of the coefficient matrix and we obtain interior gradient estimates for so-called false mean curvature equation.

Matrix inequalities

CERN Document Server

Zhan, Xingzhi

2002-01-01

The main purpose of this monograph is to report on recent developments in the field of matrix inequalities, with emphasis on useful techniques and ingenious ideas. Among other results this book contains the affirmative solutions of eight conjectures. Many theorems unify or sharpen previous inequalities. The author's aim is to streamline the ideas in the literature. The book can be read by research workers, graduate students and advanced undergraduates.

Verification of the Microgravity Active Vibration Isolation System based on Parabolic Flight

Science.gov (United States)

Zhang, Yong-kang; Dong, Wen-bo; Liu, Wei; Li, Zong-feng; Lv, Shi-meng; Sang, Xiao-ru; Yang, Yang

2017-12-01

The Microgravity active vibration isolation system (MAIS) is a device to reduce on-orbit vibration and to provide a lower gravity level for certain scientific experiments. MAIS system is made up of a stator and a floater, the stator is fixed on the spacecraft, and the floater is suspended by electromagnetic force so as to reduce the vibration from the stator. The system has 3 position sensors, 3 accelerometers, 8 Lorentz actuators, signal processing circuits and a central controller embedded in the operating software and control algorithms. For the experiments on parabolic flights, a laptop is added to MAIS for monitoring and operation, and a power module is for electric power converting. The principle of MAIS is as follows: the system samples the vibration acceleration of the floater from accelerometers, measures the displacement between stator and floater from position sensitive detectors, and computes Lorentz force current for each actuator so as to eliminate the vibration of the scientific payload, and meanwhile to avoid crashing between the stator and the floater. This is a motion control technic in 6 degrees of freedom (6-DOF) and its function could only be verified in a microgravity environment. Thanks for DLR and Novespace, we get a chance to take the DLR 27th parabolic flight campaign to make experiments to verify the 6-DOF control technic. The experiment results validate that the 6-DOF motion control technique is effective, and vibration isolation performance perfectly matches what we expected based on theoretical analysis and simulation. The MAIS has been planned on Chinese manned spacecraft for many microgravity scientific experiments, and the verification on parabolic flights is very important for its following mission. Additionally, we also test some additional function by microgravity electromagnetic suspension, such as automatic catching and locking and working in fault mode. The parabolic flight produces much useful data for these experiments.

Conversion of solar radiation using parabolic mirrors

Directory of Open Access Journals (Sweden)

Jolanta Fieducik

2017-08-01

Full Text Available The use of solar energy is a promising source of renewable energy to cover the energy needs of our society. The aim of the study will be to analyze the possibility of converting solar energy using parabolic reflectors to the heat energy needed to meet the needs of hot water for a family of 4 people. This study presents simulations of the use of solar radiation using radiant concentration systems. The parabolic mirror directs the concentrated beam of sunlight onto a tube located in the focal plane, which is filled with water that under the influence of solar radiation heats up. This article assumes constant mirror geometry and tube cross section, while simulation is performed for different coefficients. For calculations it was assumed that the reflection coefficient of sunlight from the mirror r is variable and an analysis of its effect on the amount of heated liquid is made. The radiation absorption coefficient across the tube surface was determined by a, the thermal surface emissivity coefficient was determined as e and the simulations were performed at variable values for the amount of heated liquid. The calculations and their analysis show that, with appropriately chosen coefficients, it is possible to meet the needs of a 4-person family in warm water using the proposed installation in Poland.

A Class of time-fractional hemivariational inequalities with application to frictional contact problem

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Zeng, Shengda; Migórski, Stanisław

2018-03-01

In this paper a class of elliptic hemivariational inequalities involving the time-fractional order integral operator is investigated. Exploiting the Rothe method and using the surjectivity of multivalued pseudomonotone operators, a result on existence of solution to the problem is established. Then, this abstract result is applied to provide a theorem on the weak solvability of a fractional viscoelastic contact problem. The process is quasistatic and the constitutive relation is modeled with the fractional Kelvin-Voigt law. The friction and contact conditions are described by the Clarke generalized gradient of nonconvex and nonsmooth functionals. The variational formulation of this problem leads to a fractional hemivariational inequality.

Inequality in OECD countries.

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Thévenot, Celine

2017-08-01

This article recalls the state of play of inequality levels and trends in OECD countries, with a special focus on Nordic countries. It sheds light on explaining the drivers of the rise in inequality and its economic consequences. It addresses in particular the issue of redistribution through taxes and transfers. It concludes with an overview of policy packages that should be considered to address the issue of rising inequalities.

[Inequalities in health in Italy].

Science.gov (United States)

Caiazzo, Antonio; Cardano, Mario; Cois, Ester; Costa, Giuseppe; Marinacci, Chiara; Spadea, Teresa; Vannoni, Francesca; Venturini, Lorenzo

2004-01-01

Socioeconomic inequality and its impact on health is a growing concern in the European public health debate. In many countries, the issue is moving away from description towards the identification of the determinants of inequalities and the development of policies explicitly aimed at reducing inequalities in health. In Italy, ten years after the publication of the first report on inequalities in health, this topic is seldom present on the agenda of public policy makers. The purpose of this report is to update the Italian profile of social variation in health and health care in order to stimulate the debate on ways to tackle inequalities in health that are preventable. In the first section of this book, the threefold objective is to describe the principal mechanisms involved in the generation of social inequalities in health (Introduction); to report Italian data on the distribution and magnitude of this phenomenon in the last decade; and to evaluate policies and interventions in both the social (chapter 1.9, Section I) and the health sector (chapter 2.3, Section I), which are potentially useful to reduce health inequalities. It is intended for anyone who is in a position to contribute t o decision-making that will benefit the health of communities. For this reason, chapters are organized by specific determinants of inequalities on which interentions may have an impact. The methodological approach in the second section focuses on the best methods to monitor social inequalities including recommendations on social indicators, sources of information and study models, based on European guidelines revised for the Italian situation. According to data from national and local studies, mortality increases linearly with social disadvantage for a wide range of indicators at both the individual (education, social class, income, quality of housing) and the geographical level (deprivation indexes computed at different levels of aggregation). This positive correlation is evident