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This study aims to examine the behavior of cash raised through market timing efforts and the success of such efforts in creating value to shareholders.

It is shown that in two quarters, subsequent to raising equity, cash balance of market timers is higher but after that, there is no significant difference between timers and non-timers. Results of speed of adjustment regressions indicate that market timers move faster toward their target cash levels.

Market timers are small firms that suffer from asymmetric information. They have limited access to capital market, and raising external capital is an opportunity that should be timed. The results suggest that, on average, these firms are managed by more able executives, who are 10 per cent more likely to time the market; however, it is found that timing efforts are unsuccessful in creating value to shareholders even after controlling for the mitigating effect of managerial ability. Subsequent to market timing, on average, market timers earn significantly lower abnormal return over different holding periods relative to their comparable non-timer counterparts.

Overall, the results undermine the validity of market timing as a value-maximizing financial policy.

The purpose of this paper is to investigate the heat transfer of laminar and turbulent pulsating Al203/water nanofluid flow in a two-dimensional channel. In the laminar flow range, with increasing Reynolds number (Re), the velocity gradient is increased. Also, the Nusselt number (Nu) is increased, which causes increase in the overall heat transfer rate. Additionally, in the change of flow regime from laminar to turbulent, average thermal flux and pulsation range are increased. Also, the effect of different percentage of Al₂O₃/water nanofluid is investigated. The results show that the addition of nanofluids improve thermal performance in channel, but the using of nanofluid causes a pressure drop in the channel.

The pulsatile flow and heat transfer in a two-dimensional channel were investigated.

The numerical results show that the Al₂O₃/Water nanofluid has a significant effect on the thermal properties of the different flows (laminar and turbulent) and the average thermal flux and pulsation ranges are increased in the change of flow regime from laminar to turbulent. Also, the addition of nanofluid improves thermal performance in channels.

The originality of this work lies in proposing a numerical analysis of heat transfer of pulsating Al₂O₃/Water nanofluid flow -with different percentages- in the two-dimensional channel while the flow regime change from laminar to turbulent.

The main objective of this paper is to investigate the response of human skin to an intense temperature drop at the surface. In addition, this paper aims to evaluate the efficiency of finite difference and finite volume methods in solving the highly nonlinear form of Pennes’ bioheat equation.

One-dimensional linear and nonlinear forms of Pennes’ bioheat equation with uniform grids were used to study the behavior of human skin. The specific heat capacity, thermal conductivity and blood perfusion rate were assumed to be linear functions of temperature. The nonlinear form of the bioheat equation was solved using the Newton linearization method for the finite difference method and the Picard linearization method for the finite volume method. The algorithms were validated by comparing the results from both methods.

The study demonstrated the capacity of both finite difference and finite volume methods to solve the one-dimensional and highly nonlinear form of the bioheat equation. The investigation of human skin’s thermal behavior indicated that thermal conductivity and blood perfusion rate are the most effective properties in mitigating a surface temperature drop, while specific heat capacity has a lesser impact and can be considered constant.

This paper modeled the transient heat distribution within human skin in a one-dimensional manner, using temperate-dependent physical properties. The nonlinear equation was solved with two numerical methods to ensure the validity of the results, despite the complexity of the formulation. The findings of this study can help in understanding the behavior of human skin under extreme temperature conditions, which can be beneficial in various fields, including medical and engineering.