A Novel Partitioning Method for Accelerating the Block Cimmino Algorithm

We propose a novel block-row partitioning method in order to improve the convergence rate of the block Cimmino algorithm for solving general sparse linear systems of equations. The convergence rate of the block Cimmino algorithm depends on the orthogonality among the block rows obtained by the partitioning method. The proposed method takes numerical orthogonality among block rows into account by proposing a row inner-product graph model of the coefficient matrix. In the graph partitioning formulation defined on this graph model, the partitioning objective of minimizing the cutsize directly corresponds to minimizing the sum of inter-block inner products between block rows thus leading to an improvement in the eigenvalue spectrum of the iteration matrix. This in turn leads to a significant reduction in the number of iterations required for convergence. Extensive experiments conducted on a large set of matrices confirm the validity of the proposed method against a state-of-the-art method

The launch of the euro

The introduction on January 1, 1999, of the euro--the single currency adopted by eleven of the fifteen countries of the European Union--marked the beginning of the final stage of Economic and Monetary Union and the start of a new era in Europe. The creation of a single currency and a single monetary policy has provided both extraordinary challenges and exceptional opportunities within Europe. This article reviews the organization, objectives, and targets of the euro area's new central bank and discusses some of the early challenges it has faced in setting and implementing monetary policy with the new common currency. It discusses the initial functioning of the payment system and the interbank market and reviews the effects to date of the single currency on European bond and equity markets, on the banking system, and in euro-area transactions.Euro ; European Monetary System (Organization) ; European currency unit

Convergence of numerical schemes for short wave long wave interaction equations

We consider the numerical approximation of a system of partial differential equations involving a nonlinear Schr\"odinger equation coupled with a hyperbolic conservation law. This system arises in models for the interaction of short and long waves. Using the compensated compactness method, we prove convergence of approximate solutions generated by semi-discrete finite volume type methods towards the unique entropy solution of the Cauchy problem. Some numerical examples are presented.Comment: 31 pages, 7 figure

An intrinsic Proper Generalized Decomposition for parametric symmetric elliptic problems

We introduce in this paper a technique for the reduced order approximation of parametric symmetric elliptic partial differential equations. For any given dimension, we prove the existence of an optimal subspace of at most that dimension which realizes the best approximation in mean of the error with respect to the parameter in the quadratic norm associated to the elliptic operator, between the exact solution and the Galerkin solution calculated on the subspace. This is analogous to the best approximation property of the Proper Orthogonal Decomposition (POD) subspaces, excepting that in our case the norm is parameter-depending, and then the POD optimal sub-spaces cannot be characterized by means of a spectral problem. We apply a deflation technique to build a series of approximating solutions on finite-dimensional optimal subspaces, directly in the on-line step. We prove that the partial sums converge to the continuous solutions, in mean quadratic elliptic norm.Comment: 18 page

Finance and macroeconomic volatility

Countries with more developed financial sectors, experience fewer fluctuations in real per capita output, consumption, and investment growth. But the manner in which the financial sector develops matters. The relative importance of banks in the financial system is important in explaining consumption, and investment volatility. The proportion of credit provided to the private sector, best explains volatility of consumption, and output. The authors generate their main results using fixed-effects estimates with panel data from seventy countries for the years 1956-98. Their general findings suggest that the risk management, and information processing provided by banks, maybe especially important in reducing consumption, and investment volatility. The simple availability of credit to the private sector, probably helps smooth consumption, and GDP.Economic Theory&Research,Inequality,Environmental Economics&Policies,Achieving Shared Growth,Financial Intermediation

Geography, Demography, and Early Development

This paper explores the role of geography in economic development and demographic transition. It presents a growth model where survival is endogenously determined and where the odds of survival and the returns to labor are higher in geographically favorable regions. Higher life expectancy prompts parents to devote more of their resources to old-age consumption and enjoyment. Consequently, the invest relatively more in the quantity and quality of their offspring. Investment in education, together with population growth eventually triggers technological progress. As the level of technology improves and life expectancy rises along with it, a geographically advantageous economy first enters a post-Malthusian regime during which both fertility and educational attainment increase. Then, as further improvements in technology lead to a higher education premium, such an economy undergoes a demographic transition during which life expectancy continues to rise and parents have fewer but more educated children. In regions where geography is more adverse, this transition does not take place and economies remain trapped in the Malthusian regime. Thus, accounting for the role of geography in development helps to link demographic transition to geography and shows that the latter affects the economy mostly indirectly through the impact of geography on households' demographic choices. In the early stages of development, those choices in turn determine whether economies attain the scale and scope necessary for sustained economic progress. The paper also provides a framework with which to asses why geography may matter less today.

An Experimental Study on the Strengthening of RC Frames with Soft Storey Irregularities with Different Types of Steel Diagonals

When the loss of life and property is considered, it is clear that special precautions must be taken against the earthquakes among the natural disasters. Post-earthquake observations, especially those made in the developing countries, reveal that there are many reasons for the damage and loss of life, not just one. The formation of soft storey irregularity is one of the most important factors among them. In this study, it is aimed to propose an alternative strengthening method to eliminate the adverse effects of the formation of a soft storey irregularity. Four identical frames with two stories and single span were constructed and tested under reverse cyclic loading which simulates the earthquake. The first frame among them was prepared by bonding bricks as an infill wall on two stories and it was considered to be the reference frame. In the 2nd frame, the formation of soft storey irregularity was facilitated by removing the infill wall on the lower story and the behavioral differences were examined. The remaining two frames were strengthened by using steel elements in two different diagonal shapes on the lower story. As a result, the experimental study showed that the strengthening with steel diagonal elements increased the lateral load-carrying capacity of the frame with soft storey behavior by 250% and the energy dissipation by 120% and also provided better results than the reference frame