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The purpose of this study was to fabricate a flexible inner socket with enhanced stiffness and hardness distribution by using the functional gradient method (FGM). The FGM technique can improve the comfort and flexibility of amputees through the use of a socket that is built via the direct method.

Six flexible inner socket samples were fabricated with varying weight fractions of rice husk ash-to-silicone rubber. The tensile strength and hardness of each sample were assessed. Then, numerical analyses were conducted using SOLIDWORKS software to evaluate the pressure distribution on the inner and outer layers of the flexible socket.

The hardness and stiffness of the fabricated flexible inner socket gradually increased with the weight ratio of rice husk ash-to-silicone rubber, so when it was in contact with the skin, it approximated the stiffness and hardness of the skin to ensure comfort, and when reaching a higher value in the socket contact layer, it prevented penetration through the flexible inner socket. In addition, the pressure distribution at the external layer of the flexible inner socket has improved.

A budget of US$500 limited the research to create a flexible inner socket that keeps the socket from penetrating the skin.

The FGM technique created a flexible inner socket that balances hardness and stiffness to ensure comfort and prevent wounds for its users, lower limb amputees. The commercial value resides in the accessibility of a secure and comfortable flexible inner socket for amputees worldwide, enabling them to overcome the issue of excessive stiffness typically associated with sockets made using the direct method.

This study introduces the use of FGM to fabricate a flexible inner prosthetic socket with enhanced stiffness and hardness distribution. The approach of using varying weight fractions of rice husk ash-to-silicone rubber to improve the comfort and flexibility of prosthetic sockets is a novel contribution to the field. Given the high stiffness of flexible internal sockets and their ability to maintain flexibility in the part in contact with the skin, such sockets manufactured using this method prevent pain and skin ulcers that previously occurred when sockets are manufactured via the direct method.

In recent times, ternary hybrid nanofluid has garnered attention from scientist and researchers due to its improved thermal efficiency. This study aims to delve into the examination of ternary hybrid nanofluid (Al₂O₃–Cu–TiO₂/water), particularly concerning axisymmetric flow over a nonlinearly permeable stretching/shrinking disk. In addition, the investigation of convective boundary conditions and thermal radiation effects is also considered within the context of the described flow problem.

Mathematical formulations representing this problem are reduced into a set of ordinary differential equations (ODEs) using similarity transformation. The MATLAB boundary value problem solver is then used to solve the obtained set of ODEs. The impact of considered physical parameters such as suction parameter, radiation parameter, nonlinear parameter, nanoparticle volumetric concentration and Biot number on the flow profiles as well as the physical quantities is illustrated in graphical form.

The findings revealed the thermal flux for the nonlinearly shrinking disk is approximately 1.33%, significantly higher when compared to the linearly shrinking disk. Moreover, the existence of dual solutions attributed to the nonlinear stretching/shrinking disk is unveiled, with the first solution being identified as the stable and reliable solution through temporal stability analysis.

Understanding ternary hybrid nanofluid behavior and flow has applications in engineering, energy systems and materials research. This study may help develop and optimize nanofluid systems like heat exchangers and cooling systems.

The study of flow dynamics across nonlinear stretching/shrinking disk gains less attention compared to linear stretching/shrinking geometries. Many natural and industrial processes involve nonlinear changes in boundary shapes or sizes. Understanding flow dynamics over nonlinear shrinking/stretching disks is therefore essential for applications in various fields such as materials processing, biomedical engineering and environmental sciences. Hence, this study highlights the axisymmetric flow over a nonlinear stretching/shrinking disk using ternary hybrid nanofluid composed of alumina (Al₂O₃), copper (Cu) and titania (TiO₂). Besides, this study tackles a complex problem involving multiple factors such as suction, radiation and convective boundary conditions. Analyzing such complex systems can provide valuable insights into real-world phenomena where multiple factors interact.

The authors measure the impact of culture on Sharia; Social and Financial Disclosure (SSFD) of Islamic Banks (IBs) around the world.

Content analysis is used to measure levels of disclosure for a sample of 136 IBs of 25 countries for years 2013 and 2014. Different cultural measures are used. These include secrecy/transparency as suggested by Gray (1988) and Hofstede (1980, 1983, 2001, 2010)’s culture dimensions which include: Power Distance; Individualism; Masculinity; Uncertainty Avoidance; Long-Term Ordination and Indulgence. Ordinary least square (OLS) regression is used to test the research hypotheses.

After controlling bank-specific, corporate governance and country characteristics, the authors found that Hofstede’s culture dimensions have a significant impact on SSFD. They also found that Gray's transparency dimension positively influence levels of sharia, social and aggregated disclosure. Therefore, they conclude that culture influences levels of disclosure in IBs.

This study has policy implications for managers and regulators of Islamic banking industry.

This study is the first to use both Gray and Hofstede models in the context of IBs around the world. It also the first to explore the impact of culture on three different disclosure levels for IBs.

In a modern business scenario, firms have implemented customer-centric approaches to enable customer relationship management (CRM) to trigger business excellence. Business strategies are modernizing business marketing operations that mainly focused on the retention of profitable customers. The purpose of this study is to empirically investigate the impact of marketing strategies (MS), information technology support (IT-S) and knowledge sharing (KS) in the effect of CRM in the pharmaceutical sector of Punjab, Pakistan.

Data were collected from the field force of national and international pharmaceuticals companies (N = 263) through a convenience sampling technique. Partial least squares structural equation modeling was used to examine data in SmartPLS 3.2.6.

The results indicated that IT-S and KS mediate the relationship between MS and CRM. More specifically, MS positively develops CRM through IT-S and KS.

This research contributes to the existing literature of pharmaceuticals by disclosing the field-force (medical representatives) specific role in developing CRM performance between pharmaceuticals firms and health-care physicians that are mainly based on knowledge advancement and influence these firms to adopt customer-centric business approaches to gain a competitive advantage to drive firm profitability.

The main purpose of this study is to analyze the heat transfer phenomena in a dynamically bulging enclosure filled with Cu-water nanofluid. This study examines the convective heat transfer process induced by a bulging area considered a heat source, with the enclosure's side walls having a low temperature and top and bottom walls being treated as adiabatic. Various factors, such as the Rayleigh number (Ra), nanoparticle volume fraction, Darcy effects, Hartmann number (Ha) and effects of magnetic inclination, are analyzed for their impact on the flow behavior and temperature distribution.

The finite element method (FEM) is employed for simulating variations in flow and temperature after validating the results. Solving the non-linear partial differential equations while incorporating the modified Darcy number (10⁻³ ≤ Da ≤ 10⁻¹), Ra (10³ ≤ Ra ≤ 10⁵) and Ha (0 ≤ Ha ≤ 100) as the dimensionless operational parameters.

This study demonstrates that in enclosures with dynamically positioned bulges filled with Cu-water nanofluid, heat transfer is significantly influenced by the bulge location and nanoparticle volume fraction, which alter flow and heat patterns. The varying impact of magnetic fields on heat transfer depends on the Rayleigh and Has.

The geometry configurations employed in this research have broad applications in various engineering disciplines, including heat exchangers, energy storage, biomedical systems and food processing.

This research provides insights into how different shapes of the heated bulging area impact the hydromagnetic convection of Cu-water nanofluid flow in a dynamically bulging-shaped porous system, encompassing curved surfaces and various multi-physical conditions.

The purpose of this paper is to design an output-feedback algorithm based on low-power observer (LPO), robust chattering-free controller and nonlinear disturbance observer (DO) to achieve trajectory tracking of quadrotor in the Cartesian plane.

To achieve trajectory tracking control, firstly the decoupled rotational and translational model of quadrotor are modified by introducing backstepped state-space variables. In the second step, robust integral sliding mode control is designed based on the proportional-integral-derivative (PID) technique. In the third step, a DO is constructed. In next step, the measurable outputs, i.e. rotational and translational state variables, are used to design the LPO. Finally, in the control algorithm all state variables and its rates are replaced with its estimates obtained using the state-observer.

The finding includes output-feedback control (OFC) algorithm designed by using a LPO. A modified backstepping model for rotational and rotational systems is developed prior to the design of integral sliding mode control based on PID technique. Unlike traditional high-gain observers (HGO), this paper used the LPO for state estimation of quadrotor systems to solve the problem of peaking phenomenon in HGO. Furthermore, a nonlinear DO is designed such that it attenuates disturbance with unknown magnitude and frequency. Moreover, a chattering reduction criterion has been introduced to solve the inherited chattering issue of controllers based on sliding mode technique.

This paper presents input and output data-driven model-free control algorithm. That is, only input and output of the quadrotor model are required to achieve the trajectory tracking control. Therefore, for practical implementation, the number of on-board sensor is reduced.

Although extensive research has been done for designing OFC algorithms for quadrotor, LPO has never been implemented for the rotational and translational state estimations of quadrotor. Furthermore, the mathematical model of rotational and translational systems is modified by using backstepped variables followed by the controller designed using PID and integral sliding mode control technique. Moreover, a DO is developed for attenuation of disturbance with unknown bound, magnitude and frequency.

The paper aims to study the effects of humidity on the electrical properties of copper phthalocyanine (CuPc) thin films deposited at different gravity conditions.

Surface-type samples were fabricated on glass substrates with preliminary-deposited copper electrodes. The CuPc solution was prepared in benzene. The thin films of CuPc were deposited on these substrates at diverse gravity conditions by drop-casting and centrifugation at 1 × g and 70 × g, respectively. Impedance and capacitance of the fabricated devices were measured against the different relative humidity ranging from 32 to 98 per cent.

The impedance and the capacitance of the CuPc film were found to be dependent on the ambient humidity levels (32-98 per cent) and the gravity conditions (1 × g and 70 × g) opted during the fabrication process.

The centrifugation technique can potentially be used in the instrumentation industry for the fabrication of humidity sensors.

The results of the investigations can potentially be used in the instrumentation and optoelectronics industry for the fabrication of humidity sensors.

CuPc films were deposited from a solution in benzene using drop-casting and centrifugation. The electrical properties of the films were found to be dependent on film fabrication conditions and ambient humidity levels. Growth-dependent electrical properties of the CuPc films can be explained by considering their structure.

This study investigates the flow and heat transfer in a magnetohydrodynamic (MHD) ternary hybrid nanofluid (HNF), considering the effects of viscous dissipation and radiation.

The transport equations are transformed into nondimensional partial differential equations. The local nonsimilarity (LNS) technique is implemented to truncate nonsimilar dimensionless system. The LNS truncated equation can be treated as ordinary differential equations. The numerical results of the equation are accomplished through the implementation of the bvp4c solver, which leverages the fourth-order three-stage Lobatto IIIa formula as a finite difference scheme.

The findings of a comparative investigation carried out under diverse physical limitations demonstrate that ternary HNFs exhibit remarkably elevated thermal efficiency in contrast to conventional nanofluids.

The LNS approach (Mahesh et al., 2023; Khan et al., 20223; Farooq et al., 2023) that we have proposed is not currently being used to clarify the dynamical issue of HNF via porous media. The LNS method, in conjunction with the bvp4c up to its second truncation level, yields numerical solutions to nonlinear-coupled PDEs. Relevant results of the topic at hand, obtained by adjusting the appropriate parameters, are explained and shown visually via tables and diagrams.