General Rule and Materials Design of Negative Effective U System for High-T_c Superconductivity

Based on the microscopic mechanisms of (1) charge-excitation-induced negative effective U in s^1 or d^9 electronic configurations, and (2) exchange-correlation-induced negative effective U in d^4 or d^6 electronic configurations, we propose a general rule and materials design of negative effective U system in itinerant (ionic and metallic) system for the realization of high-T_c superconductors. We design a T_c-enhancing layer (or clusters) of charge-excitation-induced negative effective $U$ connecting the superconducting layers for the realistic systems.Comment: 11 pages, 1 figures, 2 tables, APEX in printin

Asymptotic bahavior for systems of nonlinear wave equations with multiple propagation speeds in three space dimensions

We consider the Cauchy problem for systems of nonlinear wave equations with multiple propagation speeds in three space dimensions. Under the null condition for such systems, the global existence of small amplitude solutions is known. In this paper, we will show that the global solution is asymptotically free in the energy sense, by obtaining the asymptotic pointwise behavior of the derivatives of the solution. Nonetheless we can also show that the pointwise behavior of the solution itself may be quite different from that of the free solution. In connection with the above results, a theorem is also developed to characterize asymptotically free solutions for wave equations in arbitrary space dimensions.Comment: The final version. 30 page

Asymptotic Prediction Mean Squared Error for Strongly Dependent Processes with Estimated Parameters

In this paper we deal with the prediction theory of long memory processes. After investigating the general theory relating to convergence of moments of the nonlinear least squares estimators, we evaluate the asymptotic prediction mean squared error of two predictors. One is defined by using the estimator of the differencing parameter and the other is defined by using a fixed, known differencing parameter, which is, in other words, one parametric predictor of the seasonally integrated autoregressive moving average (SARIMA) models. In this paper, results do not impose the normality assumption and deal not only with stationary time series but also with nonstationary ones. The finite sample behavior is examined by simulations using the computer program S-PLUS in terms of the asymptotic theory.Mean-squared prediction errosrs, Long memory, Seasonality, Nonlinear least squares estimators, Convergence of moments

Properties of dense, asymmetric nuclear matter in Dirac-Brueckner-Hartree-Fock approach

Within the Dirac-Brueckner-Hartree-Fock approach, using the Bonn potentials, we investigate the properties of dense, asymmetric nuclear matter and apply it to neutron stars. In the actual calculations of the nucleon self-energies and the energy density of matter, we study in detail the validity of an angle-averaged approximation and an averaging of the total momentum squared of interacting two-nucleons in nuclear matter. For practical use, we provide convenient parametrizations for the equation of state for symmetric nuclear matter and pure neutron matter. We also parametrize the nucleon self-energies in terms of polynomials of nucleon momenta. Those parametrizations can accurately reproduce the numerical results up to high densities.Comment: 26 pages, 6 figures, 3 table

Closed-loop Identification of an Industrial Extrusion Process

This paper deals with the challenging problem of closed-loop identification for multivariable chemical processes and particularly the estimation of an open-loop plant model for a lab-scale industrial twin-screw extruder used in a powder coatings manufacturing line. The aim is to produce a low order efficient model in order to assist the scaling-up and the model-based control design of the manufacturing process. To achieve this goal, a two-stage indirect approach has been deployed which relies on the a-priori knowledge of the controller parameters in order to extract good estimates of the open-loop dynamics of the underlying process. As input excitation signals we have used multiple single variable step tests at various operating conditions (current industrial practice) carried out manually in order to generate the data-set which captures the dynamics of the extrusion process. In order to increase the efforts for obtaining a suitable plant model, we have employed various identification techniques, such as Prediction Error Methods (PEM) and Subspace Identification Methods (SIM) in order to generate candidate closed-loop models that fit to the original input-output process data. Then, a comparison of the estimated models was performed by means of the mean square error and data fitting criteria in order to select the model that best describes the dynamic behaviour of the extrusion process. Model validation based on closed-loop step responses also used as verification of the results

Computational Materials Design for High Critical Temperature Superconductivity in Hole-Doped Delafossite CuAlO2_2: Transparent Superconductors

We have calculated the superconducting critical temperature $T_c$ of hole-doped delafossite CuAlO$_2$ based on the first-principles calculations. According our calculation, $0.2\sim0.3$ hole-doped CuAlO$_2$ can become a phonon-mediated high-$T_c$ superconductor with $T_c\sim50$ K. In the hole-doped CuAlO$_2$, the A$_1$L$_1$ phonon mode that stretches O-Cu-O dumbbell has a strong electron-phonon interaction with electrons of the flat band in Cu 3d$_{3z^2-r^2}$ and the O 2p$_z$ anti-bonding $\pi$-band.Comment: 11pages, 7figure

Municipal Bonds : Is India ready for more?

In India, municipal development projects benefiting the public often get impeded by the political and institutional framework of the Central Government. In many cases in India, a major constraint is financing these projects. According to the 12th Finance Commission report most of the infrastructure initiatives have been stalled due to financial constraints. For instance, the shortfall in financing to achieve the water and sanitation sector goals in India’s Tenth Plan is estimated at INR 179 billion. Without the discretion to issue municipal bonds, municipalities are often dependent on transfers from the Government of India (GOI) since direct investment for these projects is difficult to secure. While municipal governments are responsible for public service provision, their ability to do so is often constrained by inadequate GOI appropriations and/or missing municipal bond markets. On the other hand, private investors often lack the incentives to invest in public service projects due to high risks and insufficient returns. As a result, the provision of public goods such as infrastructure projects can be delayed or cancelled. Tax-free municipal bonds provide a potential mechanism to bridge the financing gap. We have described the actual process of municipal bond process using the example of Corporation of Chennai and the desalination water project they propose to build. We present how tax incentives, transfers and private savings tie into the municipal bond framework. We believe that only a well performing municipality can be allowed to be fiscally independent and thus chose the Corporation of Chennai for analysis and go on to show what checks and balances are needed in the Indian scenario to support such a move towards sustainable financial decentralization. This policy paper analyzes four key dimensions of the expansion of the municipal bond market. Firstly, we analyze the driving forces for the evolution of a municipal bond market. Secondly, we develop an economic framework to value a municipal debt instrument and to estimate the optimal debt for the municipality to issue. In this section we also discuss the dynamics of the model and impacts of shocks and economic transfers on the municipal debt. Thirdly, we map the stakeholders and analyze the threats and benefits of a municipal bond issuance for these stakeholders. Finally, we recommend a framework for expansion of the municipal bond market while minimizing the potential for fiscal irresponsibility and uncontrolled growth of sub-national debt. We propose the creation of Special Municipal Zones based on strong credit rating, accrual based accounting systems, optimal debt to revenue collection ratios and a strong financial need of the municipalities. To support such Special Municipal Zones, we recommend several key changes in the institutional framework including creation of the Municipal Securities Board of India.COC Corporation of Chennai, CRISIL Credit Rating Agency in India, FED Federal Reserve Bank, GOI Government of India, HUDCO Housing and Urban Development Corporation, INR Currency code for Indian Currency Rupee, MSBI Municipal Securities Board of India, MSRB Municipal Securities Regulation Board, MWSSB Metropolitan Water Supply and Sewerage Board, RBI Reserve Bank of India, SEBI Securities and Exchange Board of India, SMZ Special Municipal Zone, TNULB Tamil Nadu Urban Local Body, ULB Urban Local Bodies (Municipality),