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The purpose of this paper is to investigate the process of fused filament fabrication (FFF) of a compliant gripper (CG) using thermoplastic polyurethane (TPU) material. The paper studies the applicability of different CG designs and the efficiency of some design parameters.

After reviewing a number of different papers, two designs were selected for a number of exploratory experiments. Using design of experiments (DOE) techniques to identify important design parameters. Finally, the efficiency of the parts was investigated.

The research finds that a simpler design sacrifices some effectiveness in exchange for a remarkable decrease in production cost. Decreasing infill percentage of previous designs and 3D printing them, out of TPU, experimenting with different parameters yields functional products. Moreover, the paper identified some key parameters for further optimization attempts of such prototypes.

The cost of conducting FFF experiments for TPU increases dramatically with product size, number of parameters studied and the number of experiments. Therefore, all three of these factors had to be kept at a minimum. Further confirmatory experiments encouraged.

This paper addresses an identified need to investigate applications of FFF and TPU in manufacturing functional efficient flexible mechanisms, grippers specifically. While most research focused on designing for increased performance, some research lacks discussion on design philosophy, as well as manufacturing issues. As the needs for flexible grippers vary from high-performance grippers to lower performance grippers created for specific functions/conditions, some effectiveness can be sacrificed to reduce cost, reduce complexity and improve applicability in different robotic assemblies and environments.

The purpose of this study is to explore how the South African government has used accounting technologies to manage the pervasive issue of racial inequality.

Premised on Foucault’s notion of governmentality, we conducted a qualitative case study. Publicly available archival data are used to determine the extent to which accounting techniques have helped to shape policy responses to racial inequality.

We show that accounting techniques and calculations give visibility to the problems of government and help design a programme to solve racial inequality. The lived experiences and impacts of racism in the workplace have been problematised, turned into statistics, and used to rationalise the need for ongoing government intervention in solving the problem. These processes underpin the development of the scorecard system, which measures the contributions firms have made towards minimising racial inequalities.

This study augments the existing body of Foucauldian literature by illustrating how power dynamics can be counteracted. We show that in governmental processes, accounting can exhibit a dual role, and these roles are not always subordinate to the analysis of political realities. The case of B-BBEE reveals the unintended consequences of utilising accounting to control the conduct of individuals or groups.

Islamic banking has undergone significant adaption since its inception. This study aims to investigate why and how Islamic banks adapt their services, using participatory financing as evidence.

A qualitative study is designed, using working capital financing and commodity operations financing in Pakistan as analytical units. The data for each analytical unit is analyzed using a qualitative content analysis, while the findings are synthesized using a cross-case synthesis method.

Findings suggest that participatory financing has undergone extensive adaptation in the Islamic banking industry of Pakistan, in the wake of resolving constraints to participatory financing and increasing its viability. Consequently, participatory finance has emerged as an attractive and viable option in Pakistan. These findings suggest that unlike in the past, where Islamic banks used to buffer themselves from the environment and ignore the market demands, they have learned to respond effectively to the market demands and the challenges posed by the environment.

Findings suggest that the adaptation strategy is more effective than the migration strategy, because it enables the financial service systems to reduce the underlying risks by avoiding emergent threats and eradicating the inherent weaknesses.

The extant literature provides a generalized view on the adaptation process that Islamic banks undergo to comply with their environment. However, it is limited in terms of conceptualizing the adaptations and innovations in their products and the underlying structural variations. The present study fills this gap.

The purpose of this paper is to improve the problem of kinematics incompatibility of human–exoskeleton in the existing rigid lower-limb exoskeleton (LLE).

In this paper, following an introduction, the motion characteristics of the human knee joint and the design method of the exoskeleton were introduced. A kinematics model of the LLE based on cross-four-bar linkage was obtained. The structural parameters of the LLE mechanism were optimized by the particle swarm optimization algorithm. The predefined trajectories used in the optimization process were derived from the ankle joint, not the instantaneous center of rotation of the knee joint. Finally, the motion deviation of the optimization result was simulated, and the human–exoskeleton coordination experiment was designed to compare with the traditional single-axis knee joint in terms of comfort and coordination.

The lower limb exoskeleton mechanism obtained in this paper has a good tracking effect on human movement and has been improved in terms of comfort and coordination compared with the traditional single-axis knee joint.

The customized exoskeleton design method introduced in this paper is relatively simple, and the obtained exoskeleton has better movement coordination than the traditional exoskeleton. It can provide a reference for the design of lower limb exoskeleton and lower limb orthosis.

Endurance time is an important factor limiting the progress of flapping-wing aircraft. In this study, this paper developed a prototype of a double-wing flapping-wing micro air vehicle (FMAV) that mimics insect-scale flapping wing for flight. Besides, novel methods for optimal selection of motor, wing length and battery to achieve prolonged endurance are proposed. The purpose of this study is increasing the flight time of double-wing FMAV by optimizing the flapping mechanism, wings, power sources, and energy sources.

The 20.4 g FMAV prototype with wingspan of 21.5 cm used an incomplete gear flapping wing mechanism. The motor parameters related to the lift-to-power ratio of the prototype were first identified and analyzed, then theoretical analysis was conducted to analyze the impact of wing length and flapping frequency on the lift-to-power ratio, followed by practical testing to validate the theoretical findings. After that, analysis and testing examined the impact of battery energy density and efficiency on endurance. Finally, the prototype’s endurance duration was calculated and tested.

The incomplete gear facilitated 180° symmetric flapping. The motor torque constant showed a positive correlation with the prototype’s lift-to-power ratio. It was also found that the prototype achieved the best lift-to-power ratio when using 100 mm wings.

A gear-driven flapping mechanism was designed, capable of smoothly achieving 180° symmetric flapping. Besides, factors affecting long-duration flight – motor, wings and battery – were identified and a theoretical flight duration analysis method was developed. The experimental result proves that the FMAV could achieve the longest hovering time of 705 s, outperforming other existing research on double-wing FMAV for improving endurance.

Component positioning is an important part of aircraft assembly, aiming at the problem that it is difficult to accurately fall into the corresponding ball socket for the ball head connected with aircraft component. This study aims to propose a ball head adaptive positioning method based on impedance control.

First, a target impedance model for ball head positioning is constructed, and a reference positioning trajectory is generated online based on the contact force between the ball head and the ball socket. Second, the target impedance parameters were optimized based on the artificial fish swarm algorithm. Third, to improve the robustness of the impedance controller in unknown environments, a controller is designed based on model reference adaptive control (MRAC) theory and an adaptive impedance control model is built in the Simulink environment. Finally, a series of ball head positioning experiments are carried out.

During the positioning of the ball head, the contact force between the ball head and the ball socket is maintained at a low level. After the positioning, the horizontal contact force between the ball head and the socket is less than 2 N. When the position of the contact environment has the same change during ball head positioning, the contact force between the ball head and the ball socket under standard impedance control will increase to 44 N, while the contact force of the ball head and the ball socket under adaptive impedance control will only increase to 19 N.

In this paper, impedance control is used to decouple the force-position relationship of the ball head during positioning, which makes the entire process of ball head positioning complete under low stress conditions. At the same time, by constructing an adaptive impedance controller based on MRAC, the robustness of the positioning system under changes in the contact environment position is greatly improved.

Soft actuators using pneumatic-chamber (PneuNet)-based designs have been of interest in the area of soft robotics with scope of application in the area of biomedical assistance and smart agriculture. Researchers have attempted to investigate multiple chambers in parallel to examine their deformation characteristics. However, there is a lacuna for investigation of the deformation characteristics of four parallel chambered soft actuators. The purpose of this study is to comprehensively investigate the different possible actuation scenarios and the resulting bending/deformation behaviours.

Therefore, in this study, a four-chambered PneuNet actuator is numerically investigated to evaluate the effects of pressurization scenarios and pressure levels on its performance, operating reaching and working volume.

The results of this study revealed that two-adjacent chamber equal pressurization and three-chamber pressurizations result in increased bending. However, two-opposite chamber pressurization reduces the bending angle with pressure levels in the lower pressure chamber. The maximum bending angle of 97° was achieved for single-chamber pressurization of 300 kPa. The two-adjacent chamber unequal pressurization can achieve a sweeping motion in the actuator along with bending. The working volume and reaching capability analysis revealed that the actuator can reach around 71% of the dimensional operating space.

The results provide fundamental guidance on the output nature of motion which can be obtained under different pressurization scenarios using the four-chambered design soft actuator, thereby making it a practical guide for implementation for useful applications.

The comprehensive pressurization scenarios and pressure level variations reported in this study will serve as fundamental operating guidelines for any practical implementation of the four-chambered PneuNet actuator.

This study aims to investigate the relationship between corporate governance characteristics and risk disclosure in Shariah-compliant financial firms operating in Kuwait. It aims to provide insights into the factors influencing risk disclosure practices within these institutions.

The research used manual content analysis to quantify risk disclosure levels in the annual reports of 47 Shariah-compliant financial companies listed in Kuwait in 2020. Subsequently, multiple regression analysis was conducted to assess the impact of various corporate governance factors on the extent of risk disclosure.

The study reveals that while Kuwaiti Shariah-compliant firms exhibit limited risk disclosure in their annual reports, larger boards and committees, along with a higher number of independent directors, positively influence the level of risk disclosure. Interestingly, the size of the Shariah supervisory boards did not show a significant impact on risk disclosure practices.

These findings hold regulatory implications for Kuwait, highlighting the need to ensure information adequacy and promote market efficiency. Additionally, they offer practical insights for managers and investors seeking to optimize fund sourcing and diversify investment portfolios within the context of Shariah-compliant financial institutions.

This study contributes to the existing literature by providing empirical evidence on the relationship between corporate governance characteristics and risk disclosure in the specific context of Shariah-compliant financial firms operating in Kuwait. Furthermore, it identifies avenues for future research to delve into the influence of additional governance factors on risk disclosure practices within this unique financial landscape.

Initial Public Offering (IPO) is a major milestone for a company. It allows a private company to issue shares to a much broader group of investors and become public. But conclusive evidence of the driving forces behind investors’ demand is yet to be identified. Therefore, the major purpose of this study is to assess the level of investors’ demand in IPO and how investors’ demand in IPOs is affected.

The study will employ 80 IPO companies of a Muslim-majority country, Bangladesh, starting from 2013 to 2021 with application of linear and quantile regressions. Apart from that, t-test will be used to compare means of groups of Shariah-compliant and non-Shariah-compliant firms and IPOs under fixed-price and book-building mechanism.

Oversubscription is higher for IPOs issued through fixed-price method compared to book-building method, but no significant difference is found in oversubscription for Shariah firms compared to non-Shariah firms based on t-tests. The authors found IPO size, firm size, IPO risk, proportion of shares offered to public, and bank interest rate to have significant impact on the IPO demand. Some models found non-Shariah compliance status of IPO companies to be a significant factor for the investors to demand IPO. Quantile regression results found board independence to have a positive association with larger, less-subscribed firms and board size to have a negative relation with IPO demand, for smaller firms with high demand.

Future studies may apply the findings to other settings, especially into the reasons behind preference for non-Shariah-compliant firms and higher demand for IPOs during higher interest rate. Equity issuing firms and issue managers can benefit from this study by wisely deciding on the proportion of shares for public, issue size and board of director composition. Shariah considerations cannot be ignored given that more information on Shariah compliance is disseminated among investors despite current non-preference for Shariah-compliant IPOs. On the other hand, institutional investors and general investors should consider firm-specific, governance and macroeconomic factors in IPO investment. Likewise, regulators would do well to bring in quality IPOs with characteristics mentioned in this study for ensuring stability of the market.

The main contribution of the study is identifying determinants of IPO demand: faith, governance, macro issues – understanding whether one or many of the above factors drive investor demand in IPOs of a Muslim-majority country will be the main contribution.

This research aims to examine the relations between Shariah compliance and earnings quality.

The authors study three Shariah features: Shariah compliance status, level of Shariah compliance (H-Score) and Shariah compliance persistence. The sample consists of 463 firms from the Middle East and North Africa from 2011 to 2018. A variable determining the level of Shariah compliance was created in accordance with the methodology of S&P 500 Shariah and its underlying index, S&P 500. Then, a probate relapse study was created to identify the link between Shariah compliance and earnings quality.

Results show that Shariah-compliant firms engage in lower earnings management compared to their Shariah-non-compliant counterparts. This paper reveals that Shariah compliance status and high level of Shariah compliance have significant positive association with earnings quality. The authors also find novel evidence that persistence of the Shariah-compliant status has a significant negative association with earnings quality.

This study only examines firms listed on MENA stock markets. It is recommended to further study different markets in addition to the emerging Arab markets in order to compare and contrast the results. Further, larger sample observations from a greater date range can be used.

Few studies have examined the earnings management behavior of Shariah-compliant firms vs Shariah-non-compliant ones in emerging markets; however, no study has focused on Shariah-compliant firms and their level of Shariah compliance. To the best of our knowledge, this is the first study which uses all four proxies for earnings quality in association with Shariah compliance and used new Shariah variables such as Level of Shariah Compliance and Persistent Shariah Compliance status.