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The problems of transient natural convection from a corrugated plate embedded in an enclosed porous medium is studied numerically. The non‐Darcian effects as well as the acceleration terms are taken into consideration in the momentum equation. The governing equations in terms of vorticity, stream function and temperature are expressed in a body‐fitted coordinates system, which were solved numerically by the finite difference method. Results are presented in terms of streamlines and isotherms, local and average Nusselt numbers, with Darcy‐Rayleigh number ranging from 0 to 1000, and Darcy number from 10^–4 to 10^–1, for several aspect ratios of the cavity and plate positions. The flow and heat transfer characteristics for a corrugated plate and a flat plate and the numerical results solved with four different mathematical models are also compared.

The variable porosity and thermal dispersion effects on natural convection in an inclined porous cavity are investigated numerically. The wall effect on porosity is approximated by an exponential function and its effect on thermal dispersion is modeled in terms of a dispersive length. Numerical results show that both variable porosity and thermal dispersion effects increase the temperature gradient adjacent to the wall resulting in the enhancement of surface heat flux. These effects become important when the dimensionless particle diameter is increased. The variable porosity effect increases the fluid velocity near the wall, consequently enhancing convective heat transfer. The Prandtl number effect on the Nusselt number is small for Prandtl number greater than one, but increases as the Prandtl number decreases below one. The effect of thermal conductivity ratio on the Nusselt number is greater at low Rayleigh numbers where conduction heat transfer is predominant. A comparison between theoretical and experimental results shows that the calculated Nusselt numbers which take into account variable porosity and thermal dispersion effects have the best agreement with experimental data.

The purpose of this paper is to study the influence of thermally stratified medium on a free convection flow from a sphere, which is rotating about the vertical axis, immersed in a stably thermally stratified medium.

An implicit finite‐difference scheme in combination with the quasi‐linearization technique is applied to obtain the steady state non‐similar solutions of the governing boundary layer equations for flow and temperature fields.

The numerical results indicate that the heat transfer rate at the wall decreases significantly with an increasing thermal stratification parameter, but its effect on the skin friction coefficients is rather minimum. In fact, the presence of thermal stratification of the medium influences the heat transfer at wall to be in opposite direction, that is, from fluids to the wall above a certain height. The heat transfer rate increases but the skin frictions decrease with the increase of Prandtl number. In particular, the effect of buoyancy force is much more sensitive for low Prandtl number fluids (Pr = 0.7, air) than that of high Prandtl number fluids (Pr = 7, water). Also the skin friction in rotating direction is less sensitive to the buoyancy force as the buoyancy force acts in the streamwise direction for the present study of thermally stratified medium.

The ambient temperature T_∞∞ is assumed to increase linearly with height $h$. The viscous dissipation term, which is usually small for natural convection flows, has been neglected in the energy equation. The flow is assumed to be axi‐symmetric. The Boussinesq approximation is invoked for the fluid properties to relate density changes to temperature changes, and to couple in this way the temperature field to the flow field.

Free convection in a thermally stratified medium occurs in many environmental processes with temperature stratification, and in industrial applications within a closed chamber with heated walls. Also, free convections associated with heat rejection systems for long‐duration deep ocean powder modules where ocean environment is stratified are examples of such type.

The research presented in this paper investigates the free convection flow on a sphere, which is rotating with a constant angular velocity along its vertical axis in a stably thermally stratified fluid.

The purpose of this paper is to provide insights into the multiple anti-corruption agencies (ACAs) in Taiwan and their conflict resolution. The birth of the Agency Against Corruption (AAC) in 2011 created the unintended consequence of sibling rivalry with the elder Ministry of Justice Investigation Bureau (MJIB).

A historical background of these agencies is discussed and followed by an analysis of the diversified conflicts among the prosecutor’s office, the AAC and the MJIB. The empirical sources of this study include 17 in-depth interviews with government officials both at ministerial level and field level, scholars and NGO representatives.

The redundancy of ACAs in Taiwan is a fact, which is extremely difficult to change in the foreseeable future in the light of current political and fiscal constraints. This paper concludes that the conflicts among multiple ACAs and their operational weaknesses will not fade away after a mere directive from their superior, the Ministry of Justice, unless genuine cooperation is put into place in various individual cases.

This paper provides a road-map for decision makers to improve collective anti-corruption performance. Taiwan’s AAC serves as the latest example testing the efficacy of the multiple specialized ACAs.

This pioneering study provides insights into Taiwan’s anti-corruption policy and practices. More investigative studies should be conducted on the effectiveness of multiple ACAs in other countries.

Among different leadership styles, scant hospitality researchers have studied the link between authentic leadership and organizational citizenship behaviors (OCBs). This article examined the associations among authentic leadership, job passion, and OCBs and examined the mediation effect of job passion.

Questionnaires were distributed to 314 Taiwan's hotel employees. Structural equation modeling was performed to examine the hypotheses of this study.

The results indicated that authentic leadership positively affects harmonious and obsessive passion and that harmonious passion positively affects OCBs directed to individuals (OCBI) and OCBs directed to the organization (OCBO), whereas obsessive passion positively affects OCBI. Furthermore, harmonious passion mediates the linkage between authentic leadership and OCBs (both OCBI and OCBO), whereas obsessive passion only mediates the linkage between authentic leadership and OCBI.

Training programs for hotel managers should incorporate courses on authentic leadership to strengthen managers' skills. Succession plans for managers should prioritize the promotion and retention of candidates with authentic leadership traits. Furthermore, managers should use authentic leadership to create a transparent employee incentive system and career development plans, thereby creating a workplace with fair rewards and opportunities for promotion.

The major contribution is that it expands the knowledge of hospitality leadership and determines the linkages among authentic leadership, job passion, and OCBs. Furthermore, job passion was revealed as a mediator in the authentic leadership–OCB association.