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The purpose of this paper is to examine the effects of Darcian drag force and radiation-conduction on unsteady two-dimensional magnetohydrodynamic flow of viscous, electrically conducting and Newtonian fluid over a vertical plate adjacent to a Darcian regime in presence of thermal radiation and transversal magnetic field. A well-tested, numerically stable Crank-Nicolson finite-difference procedure is employed for the conservation equations. Excellent agreement is obtained for numerical solutions with previously published work.

In this investigation, an efficient, accurate, extensively validated and unconditionally stable finite-difference scheme based on the Crank-Nicolson model is developed to solve the governing coupled, non-linear partial differential equations. The accuracy and effectiveness of the method are demonstrated.

Different numerical results are obtained and presented graphically to explain the effect of various physical parameters on the velocity and temperature profiles, local, as well as average, skin friction and Nusselt number. It is found that, with a rise in Darcian drag force, flow velocity and temperature are reduced, but increased for all times. Both average and local skin frictions are reduced considerably with an increase in Darcian drag force, but reversed behavior is observed for the local Nusselt number. Increasing the thermal radiation effects accelerated the flow velocity as well as the fluid temperature and wall local skin friction in a saturated porous medium, but effectively reduced the local Nusselt number and average Nusselt number at the wall. Comparison with previously published works in the limits shows excellent agreement.

The analysis is valid for unsteady, two-dimensional laminar flow of an optically thick no-gray gas, electrically conducting, and Newtonian fluid past an isothermal vertical surface adjacent to the Darcian regime with variable surface temperature. An extension to three-dimensional flow case is left for future work.

Practical interest of such study includes applications in electromagnetic lubrication, boundary cooling, bio-physical systems and in many branches of engineering and science. It is well known that the effect of thermal radiation is important in space technology and high temperature processes. Thermal radiation also plays an important role in controlling heat transfer process in polymer processing industry.

The purpose of this paper is to develop and correct the problem studied by Makinde and Mhone (2005) to a rotating vertical porous channel immersed in a Darcian porous regime in presence of a strong transverse magnetic filled and with the application of thermal radiation. In this investigation, the fluid is considered to be of viscous, electrically conducting, Newtonian and radiating and is optically thin with a relatively low density. Excellent agreement is obtained for exact solutions with those of previously published works.

In this investigation, a closed form analytical method based on the complex notations for the velocity, temperature and the pressure is developed to solve the governing coupled, non-linear partial differential equations. The accuracy and effectiveness of the method are demonstrated.

Interestingly observed that, the Lorentizian body force is not act as a drag force as in conventional MHD flows, but as an aiding body force and this will serve to accelerate the flow and boost the primary velocities. Due to the large rotation of the channel, the primary velocities are become flattered and shift towards the walls of the channel. With a rise in Darcian drag force, flow velocity and shear stress are found to reduce. Moreover, increasing thermal radiation and rotation of the channel strongly depress the shear stress, and maximum flow reversal, i.e. back flow is observed due to large Darcian resistance, thermal radiation and rotation.

The analysis is valid for unsteady, two-dimensional laminar flow of an optically thick no-gray gas, electrically conducting, and Newtonian fluid past an isothermal vertical surface adjacent to the Darcian regime with variable surface temperature. An extension to three-dimensional flow case is left for future work.

Practical interest of such study includes applications in magnetic control of molten iron flow in the steel industry, liquid metal cooling in nuclear reactors, magnetic suppression of molten semi-conducting materials and meteorology and in many branches of engineering and science. It is well known that the effect of thermal radiation is important in space technology and high-temperature processes. Thermal radiation also plays an important role in controlling heat transfer process in polymer processing industry.

The paper presents useful conclusions with the help of graphical results obtained from studying exact solutions based on complex notations for Darcian drag force, rotation of the channel and conduction-radiation heat transfer interaction by unsteady rotational flow in a vertical porous channel embedded in a Darcian porous regime under the application hydromagnetic force. The results of this study may be of interest to engineers for heat transfer augmentation and drag reduction in heat exchangers as well as MHD boundary layer control of re-entry vehicles, etc.

Islamic schools in Western secular societies are evolving in response to collective concerns over marginalization of Muslim children and communities and to increasing demands for high-quality education in the faith tradition. These schools are at the center of public debate over how they fit within secular societies. This paper aims to take a pedagogic look at the literature in the field of Islamic Education Studies.

Engaging in a collaborative thematic analytic review of this literature, in an educational hermeneutic approach, two novel themes are discerned as features of Muslim learners’ diverse educational landscapes.

The first theme, Dual Consciousness recognizes that young Muslims live parallel lives, moving between secular and faith-based schools and communities, and suggesting potential in developing cognitive flexibility across epistemic horizons. The second theme, Educational Transferables is a coalescence of abilities that young Muslims develop within sites of Islamic education, which may enhance their engagement in secular schools and societies.

In highlighting possibilities for young people’s educational well-being in both secular and Islamic schools, with significant pedagogical implications for both, the themes featured in this paper suggest that Muslim learners’ complex educational experiences make varied contributions to heterogeneous societies.

Despite ongoing forces of marginalization, expressions of Islamic education have benefits for young Muslims negotiating complex sociocultural and educational worlds. In highlighting possibilities for young people’s educational well-being in both secular and Islamic schools, with significant pedagogical implications for both, these themes suggest that Muslim educators can nurture in young people the ability for complex, conceptual integration in contribution to heterogeneous societies.

This paper develops a decision-analysis model to prioritize and select the site to establish a new hospital over different indicators such as cost, market conditions, environmental factors, government factors, locations and demographics. In this way, an integrated model is proposed under the intuitionistic fuzzy information (IFI), the standard deviation (SD), the rank-sum (RS) and the measurement of alternatives and ranking using the compromise solution (MARCOS) approach for ranking hospital sites (HSs).

The IF-SD-RS model is presented to obtain the combined weight with the objective and subjective weights of diverse sub-criteria and indicators for ranking sites to establish the hospital. The IF-MARCOS model is discussed to prioritize the various sites to establish the hospital over several crucial indicators and sub-criteria.

The authors implement the developed model on a case study of HSs assessment for the construction of new hospital. In this regard, inclusive set of 6 key indicators and 18 sub-criteria are considered for the evaluation of HSs. This study distinguished that HS (h₂) with combined utility function 0.737 achieves highest rank compared to the other three sites for the given information. Sensitivity analysis is discussed with different parameter values of sub-criteria to examine how changes in weight parameter ratings of the sub-criteria affect the prioritization of the options. Finally, comparative discussion is made with the diverse extant models to show the reasonability of the developed method.

This study aims to develop an original hybrid weighting tool called the IF-SD-RS model with the integration of IF-SD and IF-RS approaches to find the indicators' weights for prioritizing HSs. The developed integrated weighting model provides objective weight by IF-SD and subjective weight with the IF-RS model. The model presented in the paper deals with a consistent multi-attribute decision analysis (MADA) concerning the relations between indicators and sub-criteria for choosing the appropriate options using the developed IF-SD-RS-MARCOS model.

The purpose of this paper is to explore the relationship between cultural intelligence (CQ) and adult demographic profiles in the workplace.

This cross-cultural study used a self-reported demographic and a 20-item CQ scale. The demographic and CQ level of 287 adults working in Oman from different countries was evaluated.

The mean total CQ score of adults working in Oman was 4.77 + 1.53. Out of the four dimensions, this study founds higher values relating to motivational CQ followed by metacognitive and behavioral CQ with mean scores 5.22 + 1.53, 5.13 + 1.57 and 4.59 + 1.54, respectively. Significance, between-group differences (gender, age, job level, sector type, education level, nationality and study abroad), were observed in metacognitive and motivational dimensions of CQ (p < 0.001). All the regression models are significant, indicating that they express a meaningful relationship between each of the dependent variables and the variables in the model. The total CQ model explains 10.7% of the variance.

The results of this study provide additional insight to researchers in identifying the demographic profiles which predict the level of total CQ. The use of a longitudinal design to further confirm the results of this study is proposed.

The study helps practicing managers to understand the implications of cultural Intelligence and how it influences employee behavior from the perspectives of demographic perspectives.

The CQ levels of adults working in Oman vary according to their demographic profiles and the demographic profiles predict the CQ levels.

The COVID-19 pandemic and its related economic meltdown and social unrest severely challenged most countries, their societies, economies, organizations, and individual citizens. Focusing on both more and less successful country-specific initiatives to fight the pandemic and its multitude of related consequences, this chapter explores implications for leadership and effective action at the individual, organizational, and societal levels. As international management scholars and consultants, the authors document actions taken and their wide-ranging consequences in a diverse set of countries, including countries that have been more or less successful in fighting the pandemic, are geographically larger and smaller, are located in each region of the world, are economically advanced and economically developing, and that chose unique strategies versus strategies more similar to those of their neighbors. Cultural influences on leadership, strategy, and outcomes are described for 19 countries. Informed by a cross-cultural lens, the authors explore such urgent questions as: What is most important for leaders, scholars, and organizations to learn from critical, life-threatening, society-encompassing crises and grand challenges? How do leaders build and maintain trust? What types of communication are most effective at various stages of a crisis? How can we accelerate learning processes globally? How does cultural resilience emerge within rapidly changing environments of fear, shifting cultural norms, and profound challenges to core identity and meaning? This chapter invites readers and authors alike to learn from each other and to begin to discover novel and more successful approaches to tackling grand challenges. It is not definitive; we are all still learning.

In the determination of the measurement uncertainty, the GUM procedure requires the building of a measurement model that establishes a functional relationship between the measurand and all influencing quantities. Since the effort of modelling as well as quantifying the measurement uncertainties depend on the number of influencing quantities considered, the aim of this study is to determine relevant influencing quantities and to remove irrelevant ones from the dataset.

In this work, it was investigated whether the effort of modelling for the determination of measurement uncertainty can be reduced by the use of feature selection (FS) methods. For this purpose, 9 different FS methods were tested on 16 artificial test datasets, whose properties (number of data points, number of features, complexity, features with low influence and redundant features) were varied via a design of experiments.

Based on a success metric, the stability, universality and complexity of the method, two FS methods could be identified that reliably identify relevant and irrelevant influencing quantities for a measurement model.

For the first time, FS methods were applied to datasets with properties of classical measurement processes. The simulation-based results serve as a basis for further research in the field of FS for measurement models. The identified algorithms will be applied to real measurement processes in the future.

The purpose of this paper is to study the effect of nano alumina (Al₂O₃) on the properties of fresh concrete, hardened concrete and microstructure of concrete incorporated with high range water reducer (HRWR). This initiative was taken to improve characteristic properties of concrete using nano alumina because nano alumina can be easily be manufactured from a scrap of industrial aluminum products, so its incorporation in concrete will not only reduce industrial aluminum waste but will also change the morphology of concrete at the microstructural level.

To accomplish the objectives of the research, four different concrete mixes with the constant water–cement ratio (W/C) and superplasticizer (SP) content 0.4 and 0.6% by weight of cement, respectively, were prepared, whereas nano alumina content was altered by 0.3% and 0.4% by weight of cement. Fresh property of concrete was analyzed by using slump cone test, whereas hardened properties of concrete were analyzed through compression test and flexural strength test. The interaction of nano alumina with concrete composite was evaluated using an X-ray diffraction test.

It was observed that 0.6% superplasticizer by weight of cement increased workability by 22% but with the addition of 0.3%, nano alumina by weight of cement workability decreased by 31%. Compressive strength increased by 4.88% with the addition of 0.6% superplasticizer but with the addition of 0.3% nano alumina by weight of cement compressive strength increased by 18.60%. Also, flexural strength increased by 1.21% with the addition of 0.6% superplasticizer by weight of cement but with the addition of 0.3% nano alumina by weight of cement flexural strength increased by 8.76%. With the addition of superplasticizer, alite and belite phases remained un-hydrated but with the addition of nano alumina alite phase was hydrated while belite phase was un-hydrated. The size of belite crystals in mixes having nano alumina was less than that of mix having 0.6% superplasticizer. Also with the addition of nano alumina, a calcium aluminum silicate phase was formed which was responsible for the increment of strength in mixes having nano alumina.

Incorporation nano alumina (Al₂O₃) in concrete will not only reduce industrial aluminum waste but will also reduce CO₂ emission. Nano alumina (Al₂O₃) also changes morphology of concrete at micro structural level.

This study examines the volatility of inflation in Indonesia before and during COVID-19, focusing on people’s purchasing power. The high inflation variability makes future price expectations uncertain, creating risks in the long run and uncertainty in wealth redistribution. The ARIMA model was used from January 2005 to June 2020. The results show that the ARMA (0.1) model is suitable for testing inflation volatility in Indonesia. Forecasting results show that inflation for the next six months will still be under pressure due to COVID-19.

The purpose of this paper is to explore how different forms of integration interact with environmental dynamism to influence the outcomes of a buyer–supplier relationship (BSR). Specifically, the authors assess the impact of communication, operational process integration (OPI) and joint knowledge exploration (JKE) on the economic value and competitive differentiation generated by the BSR. Furthermore, the authors assess the moderating role of environmental dynamism in changing the performance implications of these different forms of integration.

The authors empirically test the theoretical model using survey data collected from North America. The authors apply techniques such as confirmatory factor analysis, regression and a variety of robustness checks to ensure the validity of the findings.

The results indicate that OPI and JKE are useful in generating higher value from key supply chain relationships. However, communication does not directly influence performance outcomes, rather it assists in the implementation of other forms of integration. In stable environments, better returns can be obtained from focusing on OPI, while in dynamic environments JKE becomes far more important.

This study shows that different aspects of integration have very different performance implications and that selective integration can outperform broad-based integration in some conditions. More importantly, the performance implications depend on environmental dynamism in unique ways, where greater integration is not always the best response to dynamic business conditions. The results allow managers to make better decisions regarding what forms of integration to establish in key supply chain relationships.