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Visual feedback control is a promising solution for robots work in unstructured environments, and this is accomplished by estimation of the time derivative relationship between the image features and the robot moving. While some of the drawbacks associated with most visual servoing (VS) approaches include the vision–motor mapping computation and the robots’ dynamic performance, the problem of designing optimal and more effective VS systems still remains challenging. Thus, the purpose of this paper is to propose and evaluate the VS method for robots in an unstructured environment.

This paper presents a new model-free VS control of a robotic manipulator, for which an adaptive estimator aid by network learning is proposed using online estimation of the vision–motor mapping relationship in an environment without the knowledge of statistical noise. Based on the adaptive estimator, a model-free VS schema was constructed by introducing an active disturbance rejection control (ADRC). In our schema, the VS system was designed independently of the robot kinematic model.

The various simulations and experiments were conducted to verify the proposed approach by using an eye-in-hand robot manipulator without calibration and vision depth information, which can improve the autonomous maneuverability of the robot and also allow the robot to adapt its motion according to the image feature changes in real time. In the current method, the image feature trajectory was stable in the camera field range, and the robot’s end motion trajectory did not exhibit shock retreat. The results showed that the steady-state errors of image features was within 19.74 pixels, the robot positioning was stable within 1.53 mm and 0.0373 rad and the convergence rate of the control system was less than 7.21 s in real grasping tasks.

Compared with traditional Kalman filtering for image-based VS and position-based VS methods, this paper adopts the model-free VS method based on the adaptive mapping estimator combination with the ADRC controller, which is effective for improving the dynamic performance of robot systems. The proposed model-free VS schema is suitable for robots’ grasping manipulation in unstructured environments.

This article examines the role the Australian Trade Union Training Authority (TUTA) played in international education through the provision of trade union courses and exchanges. We consider how an investigation of trade union networks contributes to a richer understanding of international education linkages.

This paper is based on research conducted for an Australian Research Council (ARC)-funded project: Trade union training: reshaping the Australian industrial landscape (ARC LP180100500). This research involved a critical analysis of 60 semi-structured oral history interviews and textual archives, including the official records held by the National Archives of Australia and papers held by the Noel Butlin Archives, the Australian Council of Trade Unions and in private collections.

TUTA was established primarily as a national union training organisation, but from its inception, it also acted as a hub for the development of regional and international labour networks. The nature of TUTA’s work placed it at the intersection of international trade union and educational domains. Although there were some points of contact with formal international programs (e.g. Japan–Australia and Kellogg Foundations, the Colombo Plan and US Department of Labour exchanges schemes), the specific contribution of TUTA is overlooked in the educational exchange literature. The role of TUTA is revealed through institutional connections and individual experiences.

Further research is required to gain a deeper understanding of the impact of TUTA from the perspective of former participants in international TUTA course and current and former trade unionists in the Asia–Pacific.

This article builds new knowledge by examining the connections forged in the Asia–Pacific region at the intersection of trade union and educational networks, an area often overlooked in the literature on educational exchange.

This paper aims to reduce waste management and generate wealth by investigating the novelty of combining chicken feather fiber and bamboo particles to produce hybrid biocomposites. This is part of responsible production and sustainability techniques for sustainable development goals. This study aims to broaden animal and plant fiber utilization in the sustainable production of epoxy resins for engineering applications.

This research used two reinforcing materials [chicken feather fiber (CFF) and bamboo particles (BP)] to reinforce epoxy resin. The BPs were kept constant at 6 Wt.%, while the CFF was varied within 3–15 Wt.% in the composites to make CFF-BP polymer-reinforced composite (CFF-BP PRC). The mechanical experiment showed a 21% reduction in densities, making the CFF-BP PRC an excellent choice for lightweight applications.

It was discovered that fabricated composites with 10 mm CFF length had improved properties compared with the 15 mm CFF length and pristine samples, which confirmed that short fibers are better at enhancing randomly dispersed fibers in the epoxy matrix. However, the ballistic properties of both samples matched. There is a 40% increase in tensile strength and a 54% increase in flexural strength of the CFF-BP PRC compared to the pristine sample.

According to the literature review, to the best of the authors’ knowledge, this is a novel study of chicken fiber and bamboo particles in reinforcing epoxy composite.

Despite the large number of Indonesian health-care workers working as migrant care workers in Japan, there is a lack of studies that have investigated this phenomenon or assessed the working conditions of Indonesian care workers working in Japanese aged-care facilities. This study aims to explore the work experiences of Indonesian care workers in Japan.

A qualitative descriptive research design was used, and a purposive sample of 18 Indonesian health-care workers (12 nurses and six midwives) who work as care workers in Japan participated in this study. Semistructured interviews were conducted with these participants between December 2022 and January 2023. The data were analyzed using content analysis. The Consolidated Criteria for Reporting Qualitative Research checklist was used to report this study.

Four key themes emerged from the data: easy but mentally challenging, being a care worker is a blessing, working in a partially Muslim-friendly environment and enjoy living: prefer to stay longer.

The work experiences of Indonesian care workers in Japan are complex and multifaceted. By understanding their experiences and needs, the authors can work toward creating more inclusive and supportive workplaces for all.

Material extrusion-based additive manufacturing is a prominent manufacturing technique to fabricate complex geometrical three-dimensional (3D) parts. Despite the indisputable advantages of material extrusion-based technique, the poor surface and subsurface integrity hinder the industrial application of this technology. The purpose of this study is introducing the hot air jet treatment (HAJ) technique for surface treatment of additive manufactured parts.

In the presented research, novel theoretical formulation and finite element models are developed to study and model the polishing mechanism of printed parts surface through the HAJ technique. The model correlates reflow material volume, layer width and layer height. The reflow material volume is a function of treatment temperature, treatment velocity and HAJ velocity. The values of reflow material volume are obtained through the finite element modeling model due to the complexity of the interactions between thermal and mechanical phenomena. The theoretical model presumptions are validated through experiments, and the results show that the treatment parameters have a significant impact on the surface characteristics, hardness and dimensional variations of the treated surface.

The results demonstrate that the average value of error between the calculated theoretical results and experimental results is 14.3%. Meanwhile, the 3D plots of Ra and Rq revealed that the maximum values of Ra and Rq reduction percentages at 255°C, 270°C, 285°C and 300°C treatment temperatures are (35.9%, 33.9%), (77.6%,76.4%), (94%, 93.8%) and (85.1%, 84%), respectively. The scanning electron microscope results illustrate three different treatment zones and the treatment-induced and manufacturing-induced entrapped air relief phenomenon. The measured results of hardness variation percentages and dimensional deviation percentages at different regimes are (8.33%, 0.19%), (10.55%, 0.31%) and (−0.27%, 0.34%), respectively.

While some studies have investigated the effect of the HAJ process on the structural integrity of manufactured items, there is a dearth of research on the underlying treatment mechanism, the integrity of the treated surface and the subsurface characteristics of the treated surface.