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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 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.

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.

The primary aim of this paper is to present a novel design approach for a ring voltage-controlled oscillator (VCO) suitable for L-band applications, whose oscillation frequency is less sensitive to power supply variations. In a few decades, with the advancement of modern wireless communication equipment, there has been an increasing demand for low-power and robust communication systems for longer battery life. A sudden drop in power significantly affects the performance of the VCO. Supply insensitive circuit design is the backbone of uninterrupted VCO performance. Because of their important roles in a variety of applications, VCOs and phase locked loops (PLLs) have been the subject of significant research for decades. For a few decades, the VCO has been one of the major components used to provide a local frequency signal to the PLL.

First, this paper chose to present recent developments on implemented techniques of ring VCO design for various applications. A complementary metal oxide semiconductor (CMOS)-based supply compensation technique is presented, which aims to reduce the change in oscillation frequency with the supply. The proposed circuit is designed and simulated on Cadence Virtuoso in 0.18 µm CMOS process under 1.8 V power supply. Active differential configuration with a cross-coupled NMOS structure is designed, which eliminates losses and negates supply noise. The proposed VCO is designed for excellent performance in many areas, including the L-band microwave frequency range, supply sensitivity, occupied area, power consumption and phase noise.

This work provides the complete design aspect of a novel ring VCO design for the L-band frequency range, low phase noise, low occupied area and low power applications. The maximum value of the supply sensitivity for the proposed ring VCO is 1.31, which is achieved by changing the VDD by ±0.5%. A tuning frequency range of 1.47–1.81 GHz is achieved, which falls within the L-band frequency range. This frequency range is achieved by varying the control voltage from 0.0 to 0.8 V, which shows that the proposed ring VCO is also suitable for low voltage regions. The total power consumed by the proposed ring VCO is 14.70 mW, a remarkably low value using this large transistor count. The achievable value of phase noise is −88.76 dBc/Hz @ 1 MHz offset frequency, which is a relatively small value. The performance of the proposed ring VCO is also evaluated by the figure of merit, achieving −163.13 dBc/Hz, which assures the specificity of the proposed design. The process and temperature variation simulations also validate the proposed design. The proposed oscillator occupied an extremely small area of only 0.00019 mm² compared to contemporary designs.

The proposed CMOS-based supply compensation method is a unique design with the size and other parameters of the components used. All the data and results obtained show its originality in comparison with other designs. The obtained results are preserved to the fullest extent.

Piezoelectric materials are widely used as actuators, due to the advantages of quick response, high sensitivity and linear strain-electric field relationship. The previous work on the piezoelectric material plate structures is not enough; however, such structures play a very important role in the practical design. In this paper, the actuation performance of piezoelectric laminated plate actuator (PLPA) is analyzed based on Galerkin method to parametric study the shape control.

In this paper, the actuation performance of PLPA is analyzed based on Galerkin method to parametric study the shape control. The stress components of the matrix plate are formulated based on electro-mechanical coupling theory and Kirchhoff's classical laminated plate theory. The effectiveness of the developed method is validated by the comparison with finite element method.

The actuation performance of PLPA and its influencing factors are numerically analyzed through the developed method. The deflection of PLPA is reasonably increased by optimizing the electric fields, the piezoelectric patch and the matrix plate.

The Galerkin method can be used for engineering applications more easily, and it does not require to rebuild the calculation model as finite element method during the calculation and analysis of PLPA. This paper is a valuable reference for the design and analysis of PLPAs.