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Fanwing airfoil is a new lift‐generating section invented in 1997 by Patrick Peebles. The early shape of the airfoil has not changed until now. So far, no research has been done to change or modify the airfoil shape in order to improve its aerodynamic performance. In this paper, possibility of changing the airfoil shape to improve its aerodynamic performance is studied. For this purpose, six different geometric shapes of the airfoil are investigated numerically to determine the best airfoil on the basis of lift and drag coefficients. Flow over the airfoil is solved by developing a computational fluid dynamics (CFD) code. The purpose of this paper is to find a more efficient configuration for the Fanwing airfoil with lower power consumption and better performance.

Flow over the airfoil is investigated by CFD. At the airfoil solid walls, the no slip condition is applied. Re‐Normalization Group k‐ε model is used for turbulence modeling. The pressure‐velocity coupling is calculated by the SIMPLEC algorithm. Second‐order upwind discretization is considered for the convection terms. Finite volume method with rectangular computational cells is used for the entire solution domain.

It is observed that the airfoil with curved bottom wall and a slot in upper wall has the maximum lift coefficient. Also, the airfoil with curved bottom wall and no slot has the minimum drag or maximum thrust (negative drag) coefficient. Therefore, instead of increasing the airfoil lift or decreasing its drag by enhancing driving motor speed with larger energy consumption, this can be done only by changing the airfoil shape. It is perceived that the airfoil lift coefficient can be augmented at least 10 percent and its drag can be reduced more than 2.8 percent only by changing its shape and no excessive power consumption. Since the airfoil shape is modified, these advantages are permanent and its benefits are cumulative through time. Eccentric vortex inside the cross flow fan that is reported earlier in the research paper is found in this airfoil, too. In addition, velocity vectors, contours of static pressure and distribution of the static pressure over the airfoils surfaces are illustrated for better understanding of the flow details.

Since the airfoil shape is very complicated for numerical study, two‐dimensional simulation has been carried out. Also, flow over the airfoil is considered steady‐state and incompressible.

In this paper, some modifications for the Fanwing airfoil are suggested in order to improve its aerodynamic performance. This is the first research for changing the configuration of the Fanwing airfoil and can be very helpful for the researchers involved in this topic as well as aerospace industries.

This paper is valuable for researchers in the new and up to date concept of the Fanwing airfoil. This work is original.

The aim of this chapter is to contribute toward the phenomena of women entrepreneurship from an emerging economy perspective through a dynamic capability's perspective. The challenges faced by women entrepreneurs in a nonsupportive entrepreneurial ecosystem reshaped by digitization will contribute to the burgeoning women entrepreneurship literature. In order to survive in a challenging entrepreneurial ecosystem, women entrepreneurs need dynamic capabilities to face the challenges of a modern digital world. This chapter problematizes the challenges of the digital world and its role in modern day businesses.

This study aims to investigate the differences in participation patterns between children with autism spectrum disorders (ASD) and children with typical development (TD) in Jordan.

The study used a cross-sectional comparative design and convenient and snowball sampling. The sample consisted of 60 children (30 ASD and 30 TD), mean age (nine years), who completed the Children’s Assessment of Participation and Enjoyment and the Preferences for Activities of Children (CAPE/PAC) via interview. Analyses consisted of descriptive statistics and Mann-Whitney U tests.

Children with ASD had significantly lower participation Diversity (U = 24.00, p < 0.000) and Intensity (U = 110.00, p < 0.000) than children with TD. In addition, children with ASD had significantly lower participation preference in Physical (U = 145.50, p < 0.000), Self-Improvement (U = 163.50, p < 0.000), Skill-Based (U = 281.00, p = 0.01), Social activities (U = 307.50, p = 0.03) and total PAC scale score (U = 246.50, p = 0.003). However, children with ASD had significantly higher Enjoyment (U = 274, p < 0.000) than children with TD.

Children with ASD have restricted participation patterns due to certain ASD features like extreme sensory processing patterns. However, limited research compared participation patterns between school-aged children with ASD and children with TD. This study concluded that participation patterns in children with ASD are different from children with TD.

The mine sequencing problem is NP-hard. Therefore, simplifying it is necessary. One way to do this is to employ clusters as input instead of individual blocks. The mining cut clustering problem has been little addressed in the literature, and the solutions used are almost always heuristic. We solve the mining cut clustering problem, which is NP-hard, through single- and multi-objective optimization, finding results that are local optima in acceptable computational time.

We first elaborate an ILP-based model to address the mining cut clustering problem. We employ a mono-objective approach and two multi-objective approaches, solving all these models by constraint programming. To choose the best solutions generated by multi-objective approaches, we employ two multi-criteria decision analysis approaches, considering different weight configurations. We developed a case study using real data.

We verified that the approaches based on multi-objective optimization performed better than the mono-objective approach for the economic return criterion. The weighted-sum multi-objective approach presented the best results considering all objective functions used. Once viable solutions were obtained through multi-objective optimization, multi-criteria decision analysis approaches almost always selected the same solution. We obtained solutions that are local optima in acceptable computational time.

This study solves an instance with 80 blocks. Consequently, it is aimed at short-term mine planning. The methodology has not yet been evaluated in large instances related to medium- and long-term mine planning.

This is the first time that multi-objective optimization has been employed to solve the mining cut custering problem. Even other problems related to mine planning were, at most, solved by goal programming, so that multi-objective optimization is a knowledge that is not widespread among mining researchers. The results are consistent, and the study achieves the objective of finding quality solutions to an NP-hard problem in an acceptable computational time.

The purpose of this study is to observe and analyze current banking practices in Pakistan, regarding the electronic customer relationship management system (ECRM). The aim is to explore the variables in relation to operational problems that may occur with banks that use ECRM and the customer's perception of the usage of e‐banking.

The research design is divided into two sections using both qualitative as well as quantitative methods to represent the results. The first section explores the variables related to the operational problems with e‐banking while the second section discusses the variables related to the customer's perception of the usage of e‐banking systems. Descriptive statistics are used to define the demographic variables while correlation is used to describe the operational problems. Cross case analysis is used to present the customer perception of e‐banking practices. In total, 40 staff members and four customers are selected as samples for this study. SPSS was used for data analysis.

Data analysis shows that customers are not ready to adopt new technologies, which results in a low level of satisfaction with e‐banking. Internet speeds and government policies are also not supportive of e‐banking in Pakistan. Owing to a lack of trust in technology and a low computer literacy rate, customers hesitate to adopt new technology. On the other hand, internet rates are too high and provided speed is in Kb/s.

The results of this study will provide some ideas and practical suggestions, which can be implemented, particularly with E‐banking in order to improve its continuance (i.e. customer satisfaction strategies as an effective means of maintaining the subscriber base, market share and the overall revenue of online banking).

The paper delineates the importance of understanding e‐banking in Pakistan and the reasons why more customers avoid using electronic banking.

Thermal conduction anisotropy, which is defined by the dependency of thermal conductivity on direction, is an important parameter in many engineering and research studies such as the design of nuclear waste depositional sites. In this context, the authors aim to investigate the effect of grain shape in thermal conduction anisotropy using pore scale modeling that utilizes real shapes of grains, pores and throats to characterize petrophysical properties of a porous medium.

The authors generalize the swelling circle approach to generate porous media composed of randomly arranged but regularly oriented elliptical grains at various grain ratios and porosities. Unlike previous studies that use fitting parameters to capture the effect of grain–grain thermal contact resistance, the authors apply roughness to grains’ surface. The authors utilize Lattice Boltzmann method to solve steady state heat conduction through medium.

Based on the results, when the temperature field is not parallel to either major or minor axes of grains, the overall heat flux vector makes a “deviation angle” with the temperature field. Deviation angle increases by augmenting the ratio of thermal conductivities of solid to fluid and the aspect ratios of grains. In addition, the authors show that porosity and surface roughness can considerably change the anisotropic properties of a porous medium whose grains are elliptical in shape.

The authors developed an algorithm for generation of non-circular-based porous medium with a novel approach to include grain surface roughness. In previous studies, the effect of grain contacts has been simulated using fitting parameters, whereas in this work, the authors impose the roughness based on the its fractal geometry.

This paper aims to examine the impact of corruption on bank stability and bank profitability separately for Islamic banks as well as conventional banks. Moreover, it also investigates whether the existence of Islamicity and corruption in the environment can moderate the Islamic banks-stability and Islamic banks-profitability relationships.

Sample of the study consists 136 banks comprising 70 Islamic and 66 conventional banks over the period 2015–2021 from nine countries with dual banking systems. Panel data fixed effect estimator with year effects is used to estimate the results.

Results of the study show that Islamicity is positively and corruption is negatively related to bank stability as well as bank profitability. Further, it is found that the effect of corruption is significantly different between Islamic and conventional banks, wherein conventional banks are more adversely affected than Islamic banks. However, an insignificant difference between Islamic and conventional banks is observed in the case of Islamicity.

The study provides theoretical and practical implications. On theoretical side, the study presents Islamicity as more reliable measure of religiosity based on Islamic values that can help in control of corruption by moderating corruption-bank stability nexus especially in dual banking economies which have high share of Muslim population. On practical side, the study recommends policy and operational measures for mitigating corruption aiming bank stability.

The results of this study contribute to the corruption-finance, religion-finance and dual banking literature. This study suggests that regulators and bank management must consider corruption and Islamicity while formulating their policies for better bank performance/stability.

The purpose of this paper is to study flap application in the airfoil comprising a cross flow fan by experiment and numerical simulation.

An airfoil was made and tested in a blowing wind tunnel. Because of complicated shape of the airfoil, distributed quantities in the flow field cannot be measured. They were computed by establishing a CFD code validated by the experimental data. The k‐ε model was used for the Reynolds stress modeling. Flow was considered incompressible, two dimensional and steady‐state. The pressure‐velocity coupling was performed by the SIMPLEC algorithm and convection terms were discretized by using the second‐order upwind discretization scheme.

Computed aerodynamic coefficients were in good agreement with the experimental results. Flap augmented lift and pitching moment coefficients of the airfoil considerably. It was perceived that the airfoil aerodynamic coefficients decrease with the Reynolds number, its lift and pitching moment coefficients increase and its drag coefficient decreases with the fan speed. Static pressure difference between the airfoil surfaces increased with the flap angle and consequently at higher flap angles it must have larger aerodynamic coefficients as proved by the experiments. This pressure difference increases with the Reynolds number that is equivalent to higher aerodynamic forces. It was shown by the numerical solution that surface pressure on the airfoil upper wall decreases with the fan speed while it is not sensitive to the fan speed on the airfoil bottom wall.

This is the first instance in which flap application in the airfoil with forced airflow provided by an integrated cross flow fan is studied.

Increasing commercial applications for small unmanned aircraft create growing challenges in providing safe flight conditions. The conventional measures to detect icing are either expensive, energy consuming or heavy. The purpose of this paper is to develop a fault identification and isolation scheme using unknown input observers to detect and isolate actuator and structural faults in simultaneous occurrence.

The fault detection scheme is based on a deviation in system parameters due to icing and lock-in-place (LIP), two faults from different categories with similar indications that require different reconfiguration actions. The obtained residual signals are selected to be triggered by desired faults, while insensitive to others.

The proposed observer is sensitive to both actuator and structural faults, and distinguishes simultaneous occurrences by insensitivity to LIP in selected residue signals. Simulation results confirm the success of the proposed system in the presence of uncertainty and disturbance.

The fault detection and isolation scheme proposed here is based on the linear model of a winged aircraft, the Aerosonde. Moreover, the faults are applied to rudder and aileron in simulations, but the design procedure for other models is provided. The designed scheme could be further implemented on a non-linear aircraft model.

Applying the proposed icing detection scheme increases detection system reliability, since fault isolation enables timely reconfiguration schemes.

The observers proposed in previous papers detected icing fault but were not insensitive to actuator faults.

The issue of export instability exerts an enduring fascination for economists with an interest in the area of economic development. Over several decades a voluminous literature has emerged embracing debates on the domestic consequences and on the causes of export instability. The purpose here is to examine these debates and an attempt is made to set out different theoretical stances, to classify and examine empirical findings, and to indicate the directions in which the debates have moved. Such a statement of a review article's purpose is, of course, incomplete without more specific delineation of the boundaries within which the general objectives are pursued. Here that delineation has three facets.