Search results for "CLOSURE"

Natural convection heat transfer in a partially—or completely—partitioned vertical rectangular enclosure

1991

Abstract The effect of symmetric partitions protruding centrally from the end walls of a rectangular vertical enclosure on heat transfer rates is investigated numerically. The enclosure has opposite isothermal walls at different temperatures. The Rayleigh number is varied from 10 4 to 10 7 and the aspect ratio from 0.5 to 10. The thickness of the partitions is fixed and equal to one tenth of the width of the enclosure. Their non-dimensional length ( L / H ) is varied from 0 (non-partitioned enclosure) to 0.5 (two separate enclosures). The effect of different thermal boundary conditions at the end walls and at the partitions is included in the investigation.

On natural convection in a single and two zone rectangular enclosure

1992

Abstract Convective heat transfer was investigated numerically for rectangular enclosures both undivided and divided in two zones by a vertical partition, and having opposite isothermal walls at different temperatures. The aspect ratio was varied from 0.1 to 16 and the Rayleigh number from 3.5 ∗ 10 3 to ∗ 10 7 (non-partitioned enclosures) and from 1.0 ∗ 10 5 to 1.6 ∗ 10 8 (partitioned enclosures). The thickness and conductivity of the partition were varied. The end wall thermal boundary conditions were adiabatic or LTP (Linear Temperature Profile). The continuity, momentum and energy equations for a 2-D laminar steady flow were solved under the Boussinesq approximation by using a finite-dif…

One-dimensional Mixed MHD Convection

2006

The parallel, fully developed flow of an electrically conducting fluid between plane parallel walls under the simultaneous influence of a driving pressure head, buoyancy, and magnetohydrodynamic (MHD) forces is studied. The fluid is assumed to be internally heated and the flow is modeled as one-dimensional and incompressible, while the Boussinesq approximation is adopted for the buoyancy terms. Analytical solutions are obtained for temperature, velocity and electrical potential under different electrical boundary conditions, forced to natural convection intensity ratios and values of the magnetic induction. Generalized working charts are presented which synthetically describe the system''s …

Independent friction-restitution modeling of two-disk collisions

2021

[EN] The oblique collisions between two axisymmetric disks moving on a flat horizontal surface are described in terms of impact modeling based on the assumption that normal and tangential restitution mechanisms operate independently of friction. Describing these mechanisms in terms of the usual Coulomb formulation, the model allows for an interpretation of some ¿anomalous¿ experimental data reported in the literature. These experimental data, corresponding to the variation of the coefficients of friction and tangential restitution with the impact angle, remained unexplained in classic formulations, are understood within the framework of the independent friction-restitution closure. Experime…

Closure to “Experimental Study of Central Baffle Flume” by F. Lotfi Kolavani, M. Bijankhan, C. Di Stefano, V. Ferro, and A. Mahdavi Mazdeh

2020

This is a Closure of the discussions on the paper “Experimental Study of Central Baffle Flume” by F. Lotfi Kolavani, M. Bijankhan, C. Di Stefano, V. Ferro, and A. Mahdavi Mazdeh

Closure to “New Stage-Discharge Equation for the SMBF Flume” by Francesco Giuseppe Carollo, Costanza Di Stefano, Vito Ferro, and Vincenzo Pampalone

2017

Corporate governance and its implications for sustainability reporting quality in Latin American business groups

2020

Abstract This paper aims to study the factors determining the quality of sustainability reporting in Latin American business groups. Applying a logistic regression model, this study is pioneer in establishing how some distinct corporate variables of business groups influence disclosure quality of Corporate Social Responsibility practices in these groups in emerging economies. The results show that control concentration in the groups negatively affects the quality of sustainability reporting. Variables such as foreign ownership, the age of the business group and board size help business groups to improve the quality of their sustainability and voluntary disclosure practices. These results fo…

An Approach to the Concept of Soft Fuzzy Proximity

2014

The purpose of this paper is to introduce the concept of soft fuzzy proximity. Firstly, we give the definitions of soft fuzzy proximity and Katsaras soft fuzzy proximity, and also we investigate the relations between the soft fuzzy proximity and slightly modified version of Katsaras soft fuzzy proximity. Secondly, we induce a soft fuzzy topology from a given soft fuzzy proximity by using soft fuzzy closure operator. Then, we obtain the initial soft fuzzy proximity from a given family of soft fuzzy proximities. So, we describe products in the category of soft fuzzy proximities. Finally, we show that a family of all soft fuzzy proximities on a given set constitutes a complete lattice.

Laser polarimetrie mit variablem Abgiech der Kornea (GDx VCC) zur Messung der retinalen Nervenfaserschicht bei primaren akuten Winkelblockglaukom

2008

Planar Cell Polarity Signaling in Collective Cell Movements During Morphogenesis and Disease

2012

Collective and directed cell movements are crucial for diverse developmental processes in the animal kingdom, but they are also involved in wound repair and disease. During these processes groups of cells are oriented within the tissue plane, which is referred to as planar cell polarity (PCP). This requires a tight regulation that is in part conducted by the PCP pathway. Although this pathway was initially characterized in flies, subsequent studies in vertebrates revealed a set of conserved core factors but also effector molecules and signal modulators, which build the fundamental PCP machinery. The PCP pathway in Drosophila regulates several developmental processes involving collective cel…