Technological Educational Institute of Western Macedonia

About: Technological Educational Institute of Western Macedonia is a based out in . It is known for research contribution in the topics: Symplectic geometry & Numerical integration. The organization has 291 authors who have published 522 publications receiving 7682 citations. The organization is also known as: TEI of West Macedonia & TEI of Western Macedonia.

New modified Runge-Kutta-Nyström methods for the numerical integration of the Schrödinger equation

Abstract: In this work we construct new Runge-Kutta-Nystrom methods especially designed to integrate exactly the test equation y^''=-w^2y. We modify two existing methods: the Runge-Kutta-Nystrom methods of fifth and sixth order. We apply the new methods to the computation of the eigenvalues of the Schrodinger equation with different potentials such as the harmonic oscillator, the doubly anharmonic oscillator and the exponential potential.

Fabrication of super-hydrophobic surfaces for enhanced stone protection

Abstract: In the current study, we demonstrate that the modification of a commercial siloxane protective composition by the addition of silica nanoparticles substantially enhances its protective efficiency and renders the treated stone surface super-hydrophobic and self-cleaning. The extent of surface hydrophobization depends on nanoparticle concentration and reaches a maximum value of ~ 160° at 1% w/v of nanoparticles for the case of white Greek marbles (Naxos, Pentelic and Thassos) treated with the modified composition. The investigation of the surface morphology by scanning electron microscopy (SEM) reveals the presence of micron-sized protrusions (10–100 μm in diameter) formed by nanoparticle aggregates consolidated by the siloxane polymer. The diameter and surface density of the protrusions depend on nanoparticle concentration. The developed nanostructure of the protrusions was observed by atomic force microscopy (AFM). The nano-dimensions of the silica particles are essential for the superhydrophobization of the treated marble surfaces. In the case of micron-sized silica particles that were mixed with siloxane and were applied accordingly on similar white Greek marbles, the superhydrophobic effect was not achieved and the observed water contact angles were substantially lower. In the event that hydrophobicity is not the sole parameter of optimal stone and stone-monuments protection, other important parameters, such as water vapor permeability, water capillary absorption and stone color alterations, were also investigated and their dependence on nanoparticle concentration was established.

Financial, governance and environmental determinants of corporate social responsible disclosure

Abstract: Purpose – The purpose of this paper is to investigate the vital determinants on the extent of corporate social responsibility (CSR) disclosure in a US context. The selected variables are CEO duality, the presence of women in the board, greenhouse gas (GHG) emissions, emission reduction initiatives, company's risk premium, financial leverage and industry's profile. Design/methodology/approach – The environmental, social and governance (ESG) disclosure score is used as a proxy for the extent of CSR disclosure calculated by Bloomberg. The influence of plausible variables on the ESG disclosure score and its sub-categories was examined by using the least squares dummy variable model (LSDV) incorporating 100 companies listed on Standard & Poor's 500 Index for the period 2009-2012. Findings – The results show that the emission reduction initiatives and GHG emissions influence positively the extent of ESG score. In addition, slight differences exist concerning the determinants of different types of disclosures. F...