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The purpose of this paper is to conduct a detailed investigation of the two-dimensional natural convection flow of a dusty fluid. Therefore, the incompressible boundary layer flow of a two-phase particulate suspension is investigated numerically over a semi-infinite vertical flat plate. Comprehensive flow formations of the gas and particle phases are given in the boundary layer region. Primitive variable formulation is employed to convert the nondimensional governing equations into the non-conserved form. Three important two-phase mechanisms are discussed, namely, water-metal mixture, oil-metal mixture and air-metal mixture.

The full coupled nonlinear system of equations is solved using implicit two point finite difference method along the whole length of the plate.

The authors have presented numerical solution of the dusty boundary layer problem. Solutions obtained are depicted through the characteristic quantities, such as, wall shear stress coefficient, wall heat transfer coefficient, velocity distribution and temperature distribution for both phases. Results are interpreted for wide range of Prandtl number Pr (0.005-1,000.0). It is observed that thin boundary layer structures can be formed when mass concentration parameter or Prandtl number (e.g. oil-metal particle mixture) are high.

The results of the study may be of some interest to the researchers of the field of chemical engineers.

The purpose of this paper is to study numerically the influence of a magnetic field on the transient free convective boundary layer flow of a nanofluid over a moving semi-infinite vertical cylinder with heat transfer

The problem is governed by the coupled non-linear partial differential equations with appropriate boundary conditions. The fluid is a water-based nanofluid containing nanoparticles of copper. The Brinkman model for dynamic viscosity and Maxwell–Garnett model for thermal conductivity are used. The governing boundary layer equations are written according to The Tiwari–Das nanofluid model. A robust, well-tested, implicit finite difference method of Crank–Nicolson type, which is unconditionally stable and convergent, is used to find the numerical solutions of the problem. The velocity and temperature profiles are studied for significant physical parameters such as the magnetic parameter, nanoparticles volume fraction and the thermal Grashof number Gr. The local skin-friction coefficient and the Nusselt number are also analysed and presented graphically.

The present computations have shown that an increase in the values of either magnetic parameter M or nanoparticle volume fraction decreases the local skin-friction coefficient, whereas the opposite effect is observed for thermal Grashof number Gr. The local Nusselt number increases with a rise in Gr and ϕ values. But an increase in M reduces the local Nusselt number.

This paper is relatively original and presents numerical investigation of transient two-dimensional laminar boundary layer free convective flow of a nanofluid over a moving semi-infinite vertical cylinder in the presence of an applied magnetic field. The present study is of immediate application to all those processes which are highly affected by heat enhancement concept and a magnetic field. Further the present study is relevant to nanofluid materials processing, chemical engineering coating operations exploiting nanomaterials and others.

The objective of this study is to investigate how country risk, different political actions from the government and bureaucratic behavior influence the activities in industry supply chains (SCs) in emerging markets. The main objective of this study is to investigate the influence of these external stakeholders’ elements to the demand-side and supply-side drivers and barriers for improving competitiveness of Ready-Made Garment (RMG) industry in the way of analyzing supply chain. Considering the phenomenon of recent change in the RMG business environment and the competitiveness issues this study uses the principles of stakeholder and resource dependence theory and aims to find out some factors which influence to make an efficient supply chain for improving competitiveness. The RMG industry of Bangladesh is the case application of this study. Following a positivist paradigm, this study adopts a two phase sequential mixed-method research design consisting of qualitative and quantitative approaches. A tentative research model is developed first based on extensive literature review. Qualitative field study is then carried out to fine tune the initial research model. Findings from the qualitative method are also used to develop measures and instruments for the next phase of quantitative method. A survey is carried out with sample of top and middle level executives of different garment companies of Dhaka city in Bangladesh and the collected quantitative data are analyzed by partial least square-based structural equation modeling. The findings support eight hypotheses. From the analysis the external stakeholders’ elements like bureaucratic behavior and country risk have significant influence to the barriers. From the internal stakeholders’ point of view the manufacturers’ and buyers’ drivers have significant influence on the competitiveness. Therefore, stakeholders need to take proper action to reduce the barriers and increase the drivers, as the drivers have positive influence to improve competitiveness.

This study has both theoretical and practical contributions. This study represents an important contribution to the theory by integrating two theoretical perceptions to identify factors of the RMG industry’s SC that affect the competitiveness of the RMG industry. This research study contributes to the understanding of both external and internal stakeholders of national and international perspectives in the RMG (textile and clothing) business. It combines the insights of stakeholder and resource dependence theories along with the concept of the SC in improving effectiveness. In a practical sense, this study certainly contributes to the Bangladeshi RMG industry. In accordance with the desire of the RMG manufacturers, the research has shown that some influential constructs of the RMG industry’s SC affect the competitiveness of the RMG industry. The outcome of the study is useful for various stakeholders of the Bangladeshi RMG industry sector ranging from the government to various private organizations. The applications of this study are extendable through further adaptation in other industries and various geographic contexts.

The purpose of this paper is to carry out a comprehensive review of some latest studies devoted to natural convection phenomenon in the enclosures because of its significant industrial applications.

Geometries of the enclosures have considerable influences on the heat transfer which will be important in energy consumption. The most useful geometries in engineering fields are treated in this literature, and their effects on the fluid flow and heat transfer are presented.

A great variety of geometries included with different physical and thermal boundary conditions, heat sources and fluid/nanofluid media are analyzed. Moreover, the results of different types of methods including experimental, analytical and numerical are obtained. Different natures of natural convection phenomenon including laminar, steady-state and transient, turbulent are covered. Overall, the present review enhances the insight of researchers into choosing the best geometry for thermal process.

A comprehensive review on the most practical geometries in the industrial application is performed.

Mentoring is an intense relationship between a senior experienced individual who is the mentor and a less experienced individual who is the protégé. Mentors provide counselling, guidance, advice, support and feedback for the protégé's personal and professional development. With the well-being of the family as the central issue in family firms, mentoring is often seen to be akin to a parent–child relationship. In Bangladesh, paternalistic and informal parental mentoring is the norm for grooming children both morally and professionally. Using six caselets of large family firms of Bangladesh, this chapter provides insight into the paternalistic style of mentoring, and also the generational differences in mentoring between the firm's owner and his successor.

To investigate the effect of viscous dissipation on unsteady, combined convective heat transfer to water near its density maximum in a rectangular cavity.

The upwind finite difference scheme along with successive over relaxation iteration technique is used to solve the governing equations for mixed convection flow of water with density maximum inversion in a rectangular cavity.

The effect of viscous dissipation was to increase the fluid temperature and resulted in the formation of vortex motion near the lower part of the cavity in an opposite direction to the central vortex. An increase in the Eckert number and Reynolds number of the flow resulted in augmented surface heat transfer rates from the top heated surface.

The analysis is valid for unsteady, two dimensional laminar flow. Isothermal conditions are assumed for the top and bottom walls. An extension to unsteady three dimensional flow case is left for future work.

The method is very useful to analyze nuclear reactor thermal/hydraulic loss of coolant transients, energy conservation, ventilation of rooms, solar energy collection, cooling of electronic equipment, dispersion of waste heat in estuaries and crystal growth in liquids.

The results of this study may be of interest to engineers interested in heat transfer augmentation of mixed convection in window cavities.

To investigate the effects of chemical reaction on natural convection heat and mass transfer from a sphere with temperature dependent viscosity.

The governing boundary layer equations are transformed into a non‐dimensional form and the resulting nonlinear system of partial differential equations are reduced to local non‐similarity boundary layer equations, which are solved numerically by very efficient implicit finite difference method together with Keller box scheme.

The effects of chemical reaction, the skin‐friction coefficients, surface heat transfer rates, velocity and concentration distribution decrease as well as the mass transfer rates and temperature distribution increase within the boundary layer.

The investigation is valid for steady two‐dimensional laminar flow. The concentration of the reactant is maintained at a constant value and the sphere is isothermal. An extension to unsteady flow with temperature dependent thermal conductivity is left for future work.

This result provides guidance to engineers about heat and mass transfer with the effects of chemical reaction from isothermal spherical surface.

Over the last decade, Jordanian Authorities and Government adopted several far‐reaching measures aimed at improving its investment environment. These measures included the introduction of International Accounting Standards (IASs) in 1990, amendment of the Companies Act in 1997 and amendments to Investment Promotion Law in 1998. This study specifically provides empirical evidence on changes in the depth of corporate disclosure after introducing IASs. In addition, the relationship between the depth of corporate disclosure and company's attributes is investigated. The outcome of the analysis reveals a slight improvement in the depth of disclosure after the introduction the IASs. The depth of disclosure seems to be associated with corporate size, audit firm status, liquidity, gearing, and profitability.

The paper's aim is to investigate the mixed convection flow of an electrically conducting and viscous incompressible fluid past an isothermal vertical surface with Joule heating in the presence of a uniform transverse magnetic field fixed relative to the surface. It was assumed that the electrical conductivity of the fluid varies linearly with the transverse velocity component.

The governing boundary layer equations were solved numerically. The boundary layer equations were first reduced to a convenient form by using two different formulations, namely, (i) the stream function formulation (SFF) and (ii) primitive variable formulation (PVF).

It was observed that both the local shear‐stress and Nusselt number increase with increasing value of local magnetic parameter, ξ.

In the present investigation, we investigated the effects of Joule heating on MHD mixed convection boundary layer flow of an electrically conducting viscous incompressible fluid past an isothermal vertical flat plate in the presence of a transverse magnetic field fixed relative to the surface of the plate. The analysis was valid for a steady, two dimensional laminar flow. An extension to three dimensional flow case is left for future work.

Here we have analyzed the problem of mixed convection flow of electrically conducting and viscous incompressible fluid past an isothermal vertical surface with viscous and Joule heating in presence of a uniform transverse magnetic field fixed relative to the surface. The work would be useful in the thermal management of heat transfer devices.

The results of this study may be of interest to engineers interested in heat exchanger design.

This paper aims to examine the legal position and utility of preamble and also to determine what role has been played by Preambles in new trends in Bangladesh and Indian Constitutional Law.

The research methodology undertaken in this project is analytical method of research and comparative research.

In this paper, the first legal and academic dispute and a matter of arguments and discussions that whether preamble should be treated as a part of constitution is discussed. Also, this paper tries to examine the matter of interpretational value of preamble, i.e. role of preamble in interpretation of constitution vis-à-vis of statutes. Finally, this paper examines in particular the details of preambles of two countries that have played a prominent part in the development of Constitutionalism in India and Bangladesh.

This research work is based on both primary and secondary data. The main sources of this study include like textbooks, journal articles, some important daily newspapers, online documents and some publications. The study has also relied on decided cases of Apex Court of Bangladesh and the Subcontinent.