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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.

This study aims to understand the practices and rules of Sharia crowdfunding policies in Indonesia given the rapid growth of financial technology and the increasing importance of crowdfunding as a funding alternative for micro, small, and medium enterprises (MSMEs).

This study used qualitative methods, exploratory methods and literature studies for data collection. The focus is on understanding the regulatory environment and institutional framework that support Sharia crowdfunding in Indonesia.

Despite a specific law regulating Sharia crowdfunding, several authoritative institutions in Indonesia offer FinTech, crowdfunding and Sharia crowdfunding services. Some regulations have been issued, such as Bank Indonesia Regulation Number 19/12/PBI/2017 and Financial Services Authority (OJK) Regulation Number 37/POJK.04/2018, which was later amended to Number 57/POJK.04/2020. This study emphasizes the crucial role of OJK in providing security guarantees for implementing FinTech, including crowdfunding. At the same time, Sharia crowdfunding also follows fatwas issued by DSN-MUI.

This study describes Sharia crowdfunding policies in Indonesia and indicates that further research could delve deeper into specific cases and examine the impact of these policies on the growth and sustainability of Sharia crowdfunding.

This study underlines the need to enhance Sharia crowdfunding standards and to create rules that explicitly address this issue. This has implications for regulatory authorities, FinTech companies and MSMEs seeking to leverage Sharia crowdfunding.

This study suggests potential social implications, including a more inclusive financial system that complies with Islamic principles and supports MSMEs' growth.

This study is unique in its focus on Sharia crowdfunding policies in Indonesia, providing a comprehensive view of the regulatory landscape and existing institutional framework.

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.

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.

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.

This study explores the association between institutional investors’ stewardship activity, disclosed under Japan’s Stewardship Code, and the R&D investments of their investee companies.

Recognizing the pivotal role of R&D investment in long-term value creation, this study uses comprehensive data from institutional investor disclosures to assess the impact of stewardship activity on their investee companies.

The findings show that investor stewardship activity is a factor that influences strategic R&D investment. Specifically, a positive association is found between code-compliant institutional investor shareholding and R&D investment, contingent on high levels of stewardship activity.

By using stewardship disclosures to measure stewardship activity, this study sheds new light on institutional investors’ role in promoting R&D investment. The findings suggest that stewardship regulation is a valid governance policy mechanism to the extent that it promotes stewardship activity. Moreover, the findings show that stewardship disclosures provide valuable information about the potential value enhancement associated with institutional shareholding.

This paper aims to improve the manufacturability of additive manufacturing (AM) for topology-optimized (TO) structures. Enhancement of manufacturability focuses on modifying geometric constraints and classifying the building orientation (BO) of AM parts to reduce stresses and support structures (SSs). To this end, artificial intelligence (AI) networks are being developed to automate design for additive manufacturing (DfAM).

This study considers three geometric constraints for their correction by convolutional autoencoders (CAEs) and transfer learning (TL). Furthermore, BOs of AM parts are classified using generative adversarial (GAN) and classification networks to reduce the SS. To verify the results, finite element analysis (FEA) is performed to compare the stresses of modified components with the original ones. Moreover, one sample is produced by the laser-based powder bed fusion (LB-PBF) in the BO predicted by the AI to observe its SSs.

CAE and TL resulted in promoting the manufacturability of TO components. FEA demonstrated that enhancing manufacturability leads to a 50% reduction in stresses. Additionally, training GAN and pre-training the ResNet-18 resulted in 80%, 95% and 96% accuracy for training, validation and testing. The production of a sample with LB-PBF demonstrated that the predicted BO by ResNet-18 does not require SSs.

This paper provides an automatic platform for DfAM of TO parts. Consequently, complex TO parts can be designed most feasibly and manufactured by AM technologies with minimal material usage, residual stresses and distortions.