Sharif Digital Repository

Thermal conductivity of nanofluids plays key rol in heat transfer capacity of fluids. adding nanoparticles to a base fluid can lead to enhancement in thermal conductivty ratio. CuO/Ethyle Glycol (EG) is one of the most applicable nanofluids for heat transfer purposes. In the present study, thermal conductivty ratio of CuO/EG nanofluid is modeled by applying Group Method of Data Hnadling and Least Square Support Vector Machine – Gentic Algorithm approaches. Results indicated that the utilized model are very accurate in predicting thermal conductivty ratio of the nanofluid. The R-squared values for the proposed model are equal to 0.994 and 0.991 by applying Group Method of Data Handling and... 

The feasibility of measuring CO2 content in biogas was evaluated in this research. Firstly, Curtipot pH simulator was used to visualize the titration behaviors of various percentages of dissolved CO2 in a wide range of concentration of NaOH solution. As a general output of those simulations, it was shown that when the titration curves of different CO2 content samples are separated enough, titration can provided precise information about the value of dissolved CO2. In addition, when the ratio of molar concentration of NaOH to the molar concentration of CO2 is in the range of 1 to 2(equivalent to stoichiometric ratio of bi-carbonate and carbonat), the separability of the curves is enough... 

This paper proposes that Self-Determination Theory (SDT) has considerable potential for filling some crucial feedback-seeking behavior (FSB) literature gaps. Some key issues are theoretically addressed. First, the influence mechanism of FSB on performance improvement may be explained by the role of motivational factors introduced by this theory in forming positive feedback reactions and the quality of feedback received by the feedback seeker. Second, SDT can be used to explain the feedback seekers' subjective well-being during the FSB process, which is almost overlooked in the FSB literature despite its importance. Third, this paper also relates motivational self-regulation mechanisms to FSB... 

In this paper, a new algorithm for solving the shortest loop design problem is presented. The shortest loop design problem is to find the shortest loop for an automated guided vehicle covering at least one edge of each department of a block layout. In this paper, first it is shown that this problem can be represented as a graph model. The properties of the presented model enable us to design a meta-heuristic based on ant colony system algorithm for solving the shortest loop design problem. Computational results show the efficiency of our algorithm in compare to the other techniques  

This research aims to predict and optimize the rate of penetration (ROP) in drilling operations using artificial intelligence. An ensemble machine learning model is implemented to forecast ROP based on drilling reports. The model is evaluated using metrics like RMSE and optimized with contour plots depicting expected trends based on weight on bit (WOB) and rotational speed per minute (RPM). Additionally, a multiple regression model is chosen to optimize the Rate of Penetration (ROP). This allows predicting and optimizing ROP using data-driven AI techniques, bridging novel technologies and traditional methods in the oil industry. The results demonstrate the feasibility of applying machine... 

This paper explores the impact of ethical philosophies on developing an authentic leader’s internalized moral perspective. It builds on prior research on moral identity, proposing that ethical philosophies such as deontology, rule utilitarianism, and virtue can be internalized over time to form an authentic leader’s internalized moral identity. The paper argues that while virtues and altruism are discussed in the authentic leadership literature, the relevance of other ethical philosophies to authentic leadership has been largely overlooked. These ethical philosophies embedded in business settings can be internalized and become integral to the content of a leader’s moral identity rather than... 

Static recrystallization and microstructural changes in austenitic stainless steel 304L were studied. The rolling experiments at 200 °C were carried out, and then, annealing treatment was made at temperatures ranging between 500 and 830 °C. A model was also developed to simulate the kinetics of non-isothermal recrystallization within the rolled steel. The distribution of plastic strains during rolling was predicted utilizing an elastic–plastic finite element formulation performed in ABAQUS/Explicit, while the predicted results were used to generate the as-rolled microstructure and to estimate the stored energy. Finally, microstructural–thermal model based on cellular automata was developed... 

In this work, non-isothermal annealing of cold-rolled 304L austenitic stainless steel was studied at temperatures ranging between 400 and 800 °C. In the first place, a dual-phase structure containing work-hardened austenite and strain-induced martensite was produced by means of multi-pass plate rolling, and then, the deformed steel was subjected to annealing heat treatments. To determine the distribution of stored strain energy in the rolling operations, an elastic–plastic finite-element modeling was conducted. Afterwards, an artificial neural network technique was coupled with the thermal-cellular automata model for prediction of martensite reversion, temperature history, and... 

A new conceptual framework of collective orientation in team contexts has recently been proposed in terms of vertical and horizontal dimensions of idiocentrism and allocentrism. A two-phase longitudinal study of 270 university students engaged in 86 academic groups partly confirmed the conceptualization by identifying four interpretable factors: vertical and horizontal idiocentrism, horizontal allocentrism, and avoiding arguments. The results of exploratory and confirmatory factor analyses and a structural model of relationships between the four dimensions in both phases of the study are reported in this article. © 2007 Sage Publications