Propagation of water waves over an infinite trench is examined here assuming linear theory where waves are incident from the direction of either negative infinity or positive infinity. For each case, the problem is reduced to solving coupled weakly singular integral equations of first kind involving horizontal component of velocity above the two edges of the trench. The integral equations are solved employing Galerkin approximation in terms of simple polynomials multiplied by appropriate weight functions whose forms are dictated by the edge conditions at the corners of the trench. The numerical estimates for reflection and transmission coefficients are depicted graphically against the wave number for different distance between the trenches and also for different heights of the asymmetric trench

World University root node

Applied Mathematics

Zeitschrift für angewandte Mathematik und Physik

Water wave propagation over an infinite trench

Generation of magneto-hydrodynamic surface wave by a moving oscillatory disturbance in a finite depth ocean bounded below by a horizontal porous bottom is presented. The governing initial-boundary value problem is solved using Laplace-Fourier transform and an integral form of the surface elevation is obtained. The asymptotic solutions for the free surface elevation are obtained using stationary phase method. The results show that both the steady-state and transient components exist where the latter decays asymptotically and steady-state is reached. It is seen that the bottom permeability has a significant impact on surface elevation. The dispersion relation is also taken into account and the phase and group velocities for deep water and shallow water are analyzed for different values of the parameters in number of figures. The results for limiting case in which the current speed and the porosity vanishes are compared with the calculations investigated earlier.

Waves in Random and Complex Media

Effects of bottom permeability on wave generation by a moving oscillatory disturbance in magneto- hydrodynamics

Global Innovation Index (2019), recognised Burundi, Malawi, Mozambique and Rwandafour low income countries in Sub-Saharan Africa who have performed impressively in innovation against their respective Gross Domestic Product (GDP). Identification of technology needs of any country play a key role in preparing policy measures and effective action towards sustainable development. Technology Needs Assessments Project, implemented through UN Environment and United Nations Environment Programme with Technical University of Denmark (UNEP DTU), sponsored by the Global Environment Facility in between 2010 and 2018 and completed two phases of Technology Needs Assessments (TNAs) in these four countries. There is one common technology need for mitigation in all these four countries has been chalked out i.e., “Ensuring access to affordable, reliable, sustainable and modern energy for all” which adheres to the 7th goal of Sustainable Development Goals (SDG) of the Agenda 2030 of the UNEP and the goal of Agenda 2063 of the African Union (AU) for the transformation of traditional sources to modern sources of energy for ensuring the access of clean and affordable electricity to all the people of Africa. Access to electricity remains very low ranges from 11.02% to 34.72% of their population with lowest in Burundi and highest in Rwanda. They are not only energy stressed country but they are also among the poorest nations of the world. This article critically investigates and reviews the Science, Technology and Innovation Policy (STIP) and programmes, S&amp;T infrastructure, Tertiary education, R&amp;D investment, Patent profiles for sustainable or clean energy from 2000-2020 in these four low income countries of Africa. Present study indicates that how the development trajectory of innovation ecosystem of these countries can be a root enabler to achieve the goals formulated in SDG 7 of the UNEP and the Agenda 2063 of the AU as well.

Library and Information Science

Journal of Scientometric Res

Innovation Ecosystem for Sustainable Energy in Low-income Countries of Africa towards the Goal of the Agenda 2030 of the UNEP and the Agenda 2063 of the AU: A Critical Review

Applied Physics

GENERAL

Chemistry

Radio Physics and Electronics

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

&nbsp;

The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

&nbsp;

It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.