An algorithm for finding a feasible solution of graph labeling problems [electronic resource]

, Article Utilitas Mathematica Publishing Incorporated ; 2007, Vol. 72, pp. 163-174 Eshghi, K. (Kourosh) ; Azimi, Parham ; Sharif University Of Technology

Abstract

Graceful labeling is one of the best known labeling methods of graphs. Despite the large number of papers published on the subject of graph labeling, there are few particular techniques to be used by researchers to gracefully label graphs. In this paper, first a new approach based on the mathematical programming technique is presented to model the graceful labeling problem. Then a “branching method” is developed to solve the problem for special classes of graphs. Computational results show the efficiency of the proposed algorithm for different classes of graphs. One of the interesting results of our model is in the class of trees. The largest tree known to be graceful has at most 27 vertices...

Applications of mathematical programming in graceful labeling of graphs [electronic resource]

, Article Journal of Applied Mathematics (Published by Hindawi) ; Vol. 10, No. 10, pp. 1-8 Eshghi, K. (Kourosh) ; Azimi, Parham ; Sharif University of Technology

Abstract

Graceful labeling is one of the best known labeling methods of graphs. Despite the large number of papers published on the subject of graph labeling, there are few particular techniques to be used by researchers to gracefully label graphs. In this paper, first a new approach based on the mathematical programming technique is presented to model the graceful labeling problem. Then a “branching method” is developed to solve the problem for special classes of graphs. Computational results show the efficiency of the proposed algorithm for different classes of graphs. One of the interesting results of our model is in the class of trees. The largest tree known to be graceful has at most 27 vertices...

Simultaneous Impact of Multiple Boiling Droplets on a Molten Phase Change Material as a Direct-Contact Solidification Method

, M.Sc. Thesis Sharif University of Technology Poureslami, Parham (Author) ; Shafii, Mohammad Behshad (Supervisor)

Abstract

Encompassing an interaction between the phase change material (PCM) and the droplets of a heat transfer fluid, the direct contact (DC) method provides a state-of-the-art solution for the meager melting and solidification rates of PCMs. In the DC procedure, when impinging on the molten PCM pool, droplets evaporate, solidifying the portion of the PCM. For the first time, the impact of single and simultaneous double ethanol droplets, having an average diameter of 2.68 mm, on the molten paraffin wax has been scrutinized exhaustively. Experiments have been carried out through high-speed imaging for various Weber numbers ranging from 179 to 464, pool temperatures from 70 to 95°C, and horizontal...

Simultaneous double droplet impact on a molten phase change material pool: An experimental investigation

, Article Physics of Fluids ; Volume 35, Issue 2 , 2023 ; 10706631 (ISSN) Poureslami, P ; Faghiri, S ; Shafii, M. B ; Sharif University of Technology

American Institute of Physics Inc 2023

Abstract

Although momentous in numerous authentic applications, multiple droplet impacts on the liquid pool are overlooked in most studies. Hence, the impingement of simultaneous double ethanol droplets on the molten phase change material (PCM) pool, instigating the evaporation of droplets and the solidification of PCM, is comprehensively scrutinized for the first time. Experiments were carried out through high-speed imaging for various Weber numbers ranging from 179 to 464, pool temperatures from 70 to 95 °C, and several horizontal impact spacing. By altering impact parameters, five distinct regimes were observed in the case of double droplets. Based on observations, regime maps were also...

Analytical solution of non-Fourier heat conduction in a 3-D hollow sphere under time-space varying boundary conditions

, Article Heliyon ; Volume 8, Issue 12 , 2022 ; 24058440 (ISSN) Akbari, S ; Faghiri, S ; Poureslami, P ; Hosseinzadeh, K ; Behshad Shafii, M ; Sharif University of Technology

Elsevier Ltd 2022

Abstract

In the current research, a comprehensive analytical technique is presented to evaluate the non-Fourier thermal behavior of a 3-D hollow sphere subjected to arbitrarily-chosen space and time dependent boundary conditions. The transient hyperbolic thermal diffusion equation is driven based upon the Cattaneo-Vernotte (C-V) model and nondimensionalized using proper dimensionless parameters. The conventional procedure of separation of variables is applied for solving the 3-D hyperbolic heat conduction equation with general boundary conditions. In order to handle the time dependency of the boundary conditions, Duhamel's theorem is employed. Furthermore, for the purpose of demonstrating the...