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Open Access
Article
Publication date: 6 May 2021

Miki Kuwabara, Koji Oba, Nao Takano, Noritoshi Nagamine, Yoko Maruyama, Nobuhiro Ito, Izumi Watanabe, Chikako Ikeda and Junichi Sakamoto

Occupational stress-relating overwork among teachers predispose to mental disorders and eventually lead to long leave from work. Although some studies have been conducted to…

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Abstract

Purpose

Occupational stress-relating overwork among teachers predispose to mental disorders and eventually lead to long leave from work. Although some studies have been conducted to assess these problems among elementary and junior high school teachers, a quantitative investigation has been limited to date. In this study, the authors sought to explore the association between overwork and mental stress among Japanese elementary and junior high school teachers.

Design/methodology/approach

An exploratory cross-sectional questionnaire survey was carried out on 294 Japanese elementary and junior high school teachers. The respondents filled a questionnaire on personal data, and occupational stress reaction was evaluated by Japanese version of Brief Job Questionnaire. Multiple linear regression model was used to evaluate the association between overwork information and psychological and physical stress.

Findings

Working during holidays was significantly likely to increase psychological and physical stress reactions among elementary school teachers (adjusted mean difference = −1.67, 95% CI: −2.81 to −0.54) and junior high school teachers (adjusted mean difference = −5.24, 95% CI: −9.60 to −0.87). A weakly positive association was found between high risk of psychological and physical stress and marital status (p = 0.005), teacher in charge of class (p = 0.015) among elementary school teachers.

Originality/value

This study indicated an association between working during holidays and psychological and physical stress reactions among elementary and junior high school teachers after adjusting for sociodemographic and work-related status. Further study for the confirmation of this finding is warranted.

Details

The Journal of Mental Health Training, Education and Practice, vol. 16 no. 3
Type: Research Article
ISSN: 1755-6228

Keywords

Article
Publication date: 20 November 2009

Blesson Varghese and Gerard McKee

The purpose of this paper is to address a classic problem – pattern formation identified by researchers in the area of swarm robotic systems – and is also motivated by the need…

Abstract

Purpose

The purpose of this paper is to address a classic problem – pattern formation identified by researchers in the area of swarm robotic systems – and is also motivated by the need for mathematical foundations in swarm systems.

Design/methodology/approach

The work is separated out as inspirations, applications, definitions, challenges and classifications of pattern formation in swarm systems based on recent literature. Further, the work proposes a mathematical model for swarm pattern formation and transformation.

Findings

A swarm pattern formation model based on mathematical foundations and macroscopic primitives is proposed. A formal definition for swarm pattern transformation and four special cases of transformation are introduced. Two general methods for transforming patterns are investigated and a comparison of the two methods is presented. The validity of the proposed models, and the feasibility of the methods investigated are confirmed on the Traer Physics and Processing environment.

Originality/value

This paper helps in understanding the limitations of existing research in pattern formation and the lack of mathematical foundations for swarm systems. The mathematical model and transformation methods introduce two key concepts, namely macroscopic primitives and a mathematical model. The exercise of implementing the proposed models on physics simulator is novel.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 2 no. 4
Type: Research Article
ISSN: 1756-378X

Keywords

Open Access
Book part
Publication date: 29 September 2023

Frederick de Moll and Akihide Inaba

In recent decades, childhood in Japan has undergone significant transformations. Government policies geared at boosting women's labor force participation, a declining fertility…

Abstract

In recent decades, childhood in Japan has undergone significant transformations. Government policies geared at boosting women's labor force participation, a declining fertility rate, rising costs of having children on the one hand, and increased spending on public childcare and support measures for families, on the other hand, contribute to these ongoing changes. Having only one child is becoming the norm while mothers' role in society is shifting. The traditional family structure is moving from the previously predominant male breadwinner model to more dual-earner families. Children now spend significant amounts of time in care and education institutions.

In this chapter, we analyze current configurations of early childhood in institutions and the family from a policy perspective and regarding children's predominant education and care arrangements. Drawing on various survey data sets and evidence from demographic statistics to pedagogical ethnographies, we look at how childcare policies and families reshape the organization of children's lives and outline how institutions and educators create learning experiences aligned with the values of a collectivist society. However, despite being deeply rooted in traditional child-rearing goals, many parents also subscribe to rigorous educational arrangements from early childhood onwards to prepare children for success in a competitive education system. The chapter finishes with an outlook on future directions of how policymakers and the ongoing institutionalization of childhood continue to change children's lives.

Details

The Emerald Handbook of Childhood and Youth in Asian Societies
Type: Book
ISBN: 978-1-80382-284-6

Keywords

Article
Publication date: 25 February 2014

S. Das, A. Ghosh and D. Banerjee

The purpose of this paper is to design woven fabrics with desired quality and low manufacturing cost by optimizing the weave parameters such as count, crimp and thread spacing of…

Abstract

Purpose

The purpose of this paper is to design woven fabrics with desired quality and low manufacturing cost by optimizing the weave parameters such as count, crimp and thread spacing of warp and weft yarns.

Design/methodology/approach

To fulfill this goal, the authors endeavor to devise a searching mechanism based on particle swarm optimization (PSO) for efficiently finding the appropriate combination of weave parameters.

Findings

The experimental validation confirms that the proposed method has an excellent search capacity to obtain the best combinations of weave parameters for producing the fabrics with requisite quality at low cost.

Practical implications

The quick response capability of the system would benefit the fabric manufacturers for efficient determination of the required weaving parameters to produce the engineered fabrics.

Originality/value

This paper offers a maiden application of PSO technique to design engineered products in textiles. The method is easy to implement and it is computationally inexpensive as fewer parameters are involved.

Details

International Journal of Clothing Science and Technology, vol. 26 no. 1
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 17 August 2015

Yong Cao, Shusheng Bi, Yueri Cai and Yuliang Wang

– This paper aims to develop a robofish with oscillating pectoral fins, and control it to mimic the bionic prototype by central pattern generators (CPGs).

Abstract

Purpose

This paper aims to develop a robofish with oscillating pectoral fins, and control it to mimic the bionic prototype by central pattern generators (CPGs).

Design/methodology/approach

First, the oscillation characteristics of the cownose ray were analyzed quantitatively. Second, a robofish with multi-joint pectoral fins was developed according to the bionic morphology and kinematics. Third, the improved phase oscillator was established, which contains a spatial asymmetric coefficient and a temporal asymmetric coefficient. Moreover, the CPG network is created to mimic the cownose ray and accomplish three-dimensional (3D) motions. Finally, the experiments were done to test the authors ' works.

Findings

The results demonstrate that the CPGs is effective to control the robofish to imitate the cownose ray realistically. In addition, the robofish is able to accomplish 3D motions of high maneuverability, and change among different swimming modes quickly and smoothly.

Originality/value

The research provides the method to develop a robofish from both 3D morphology and kinematics. The motion analysis and CPG control make sure that the robofish has the features of high maneuverability and camouflage. It is useful for military underwater applications and underwater detections in narrow environments. Second, this work lays the foundation for the autonomous 3D control. Moreover, the robotic fish can be taken as a scientific tool for the fluid bionics research.

Details

Industrial Robot: An International Journal, vol. 42 no. 5
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 18 May 2015

Hongwei Ma, Yueri Cai, Yuliang Wang, Shusheng Bi and Zhao Gong

The paper aims to develop a cownose ray-inspired robotic fish which can be propelled by oscillating and chordwise twisting pectoral fins.

Abstract

Purpose

The paper aims to develop a cownose ray-inspired robotic fish which can be propelled by oscillating and chordwise twisting pectoral fins.

Design/methodology/approach

The bionic pectoral fin which can simultaneously realize the combination of oscillating motion and chordwise twisting motion is designed based on analyzing the movement of cownose ray’s pectoral fins. The structural design and control system construction of the robotic fish are presented. Finally, a series of swimming experiments are carried out to verify the effectiveness of the design for the bionic pectoral fin.

Findings

The experimental results show that the deformation of the bionic pectoral fin can be well close to that of the cownose ray’s. The bionic pectoral fin can produce effective angle of attack, and the thrust generated can propel robotic fish effectively. Furthermore, the tests of swimming performance in the water tank show that the robotic fish can achieve a maximum forward speed of 0.43 m/s (0.94 times of body length per second) and an excellent turning maneuverability with a small radius.

Originality/value

The oscillating and pitching motion can be obtained simultaneously by the active control of chordwise twisting motion of the bionic pectoral fin, which can better imitate the movement of cownose ray’s pectoral fin. The designed bionic pectoral fin can provide an experimental platform for further study of the effect of the spanwise and chordwise flexibility on propulsion performance.

Details

Industrial Robot: An International Journal, vol. 42 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 19 October 2015

Ping Zhang, Xin Liu, Guanglong Du, Bin Liang and Xueqian Wang

The purpose of this paper is to present a markerless human–manipulators interface which maps the position and orientation of human end-effector (EE, the center of the palm) to…

Abstract

Purpose

The purpose of this paper is to present a markerless human–manipulators interface which maps the position and orientation of human end-effector (EE, the center of the palm) to those of robot EE so that the robot could copy the movement of the operator hand.

Design/methodology/approach

The tracking system of this human–manipulators interface comprises five Leap Motions (LMs) which not only makes up the narrow workspace drawback of one LM but also provides redundancies to improve the data precision. However, because of the native noises and tracking errors of the LMs, the measurement errors increase over time. To address this problem, two filter tools are integrated to obtain the relatively accurate estimation of the human EE, that is, Particle Filter for position estimation and Kalman Filter for orientation estimation. Because the operator has inherent perceptive limitations, the motions of the manipulator may be out of sync with the hand motions, so that it is hard to complete with the high performance manipulation. Therefore, in this paper, an over-damping method is adopted to improve reliability and accuracy.

Findings

A series of human–manipulators interaction experiments were carried out to verify the proposed system. Compared with the markerless and contactless methods(Kofman et al., 2007; Du and Zhang, 2015), the method described in this study is more accurate and efficient.

Originality/value

The proposed method would not hinder most natural human limb motion and allows the operator to concentrate on his/her own task, making it perform high-precision manipulations efficiently.

Details

Industrial Robot: An International Journal, vol. 42 no. 6
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 15 May 2017

Iman Kardan and Alireza Akbarzadeh

This paper aims to overcome some of the practical difficulties in assistive control of exoskeletons by developing a new assistive algorithm, called output feedback assistive…

Abstract

Purpose

This paper aims to overcome some of the practical difficulties in assistive control of exoskeletons by developing a new assistive algorithm, called output feedback assistive control (OFAC) method. This method does not require feedbacks from force, electromyography (EMG) or acceleration signals or even their estimated values.

Design/methodology/approach

The presented controller uses feedbacks from position and velocity of the output link of series elastic actuators (SEAs) to increase the apparent integral admittance of the assisted systems. Optimal controller coefficients are obtained by maximizing the assistance ratio subjected to constraints of stability, coupled stability and a newly defined comfort measure.

Findings

The results confirm the effectiveness of using the inherent properties of SEAs for removing the need for extra controversial sensors in assistive control of 1 degree of freedom (1-DOF) SEA powered exoskeletons. The results also clearly indicate the successful performance of the OFAC method in reducing the external forces required for moving the assisted systems.

Practical implications

As the provided experiments indicate, the proposed method can be easily applied to single DOF compliantly actuated exoskeletons to provide a more reliable assistance with lower costs. This is achieved by removing the need for extra controversial sensors.

Originality/value

This paper proposes a novel assistive controller for SEA-powered exoskeletons with a simple model-free structure and independent of any information about interaction forces and future paths of the system. It also removes the requirement for the extra sensors and transforms the assistive control of the compliantly actuated systems into a simpler problem of position control of the SEA motor.

Details

Industrial Robot: An International Journal, vol. 44 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 16 April 2018

Vahab Khoshdel and Alireza Akbarzadeh

This paper aims to present an application of design of experiments techniques to determine the optimized parameters of artificial neural networks (ANNs), which are used to…

Abstract

Purpose

This paper aims to present an application of design of experiments techniques to determine the optimized parameters of artificial neural networks (ANNs), which are used to estimate human force from Electromyogram (sEMG) signals for rehabilitation robotics. Physiotherapists believe, to make a precise therapeutic exercise, we need to design and perform therapeutic exercise base on patient muscle activity. Therefore, sEMG signals are the best tool for using in therapeutic robots because they are related to the muscle activity. Using sEMG signals as input for therapeutic robots need precise human force estimation from sEMG. Furthermore, the ANN estimator performance is highly dependent on the accuracy of the target date and setting parameters.

Design/methodology/approach

In the previous studies, the force data, which are collected from the force sensors or dynameters, has widely been used as target data in the training phase of learning ANN. However, force sensors or dynameters could measure only contact force. Therefore, the authors consider the contact force, limb’s dynamic and time in target data to increase the accuracy of target data.

Findings

There are plenty of algorithms that are used to obtain optimal ANN settings. However, to the best of our knowledge, they do not use regression analysis to model the effect of each parameter, as well as present the contribution percentage and significance level of the ANN parameters for force estimation.

Originality/value

In this paper, a new model to estimate the force from sEMG signals is presented. In this method, the sum of the limb’s dynamics and the contact force is used as target data in the training phase. To determine the limb’s dynamics, the patient’s body and the rehabilitation robot are modeled in OpenSim. Furthermore, in this paper, sEMG experimental data are collected and the ANN parameters based on an orthogonal array design table are regulated to train the ANN. Taguchi is used to find the optimal parameters settings. Next, analysis of variance technique is used to obtain significance level, as well as contribution percentage of each parameter, to optimize ANN’s modeling in human force estimation. The results indicate that the presented model can precisely estimate human force from sEMG signals.

Details

Industrial Robot: An International Journal, vol. 45 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 25 February 2014

Mitsuyo Sakamoto and Lumi Tamanyu

The purpose of this study is to investigate a four-year mentorship program for Japanese graduate students at a private university in Tokyo, Japan. The following research questions…

Abstract

Purpose

The purpose of this study is to investigate a four-year mentorship program for Japanese graduate students at a private university in Tokyo, Japan. The following research questions were investigated: First, does mentorship provide effective and adequate preparation needed for graduate students to perform competitively (e.g. attending conferences, publishing in journals, etc.) in academic forums? Second, what kinds of benefits are gained by the mentees? Third, what factors are conducive to the benefits accrued by the mentees? Fourth, what are the obstacles to providing an effective mentorship program?

Design/methodology/approach

Adopting narrative approach as its research method, this study collected and analyzed reflective essays from 13 Japanese students in a TESOL (Teaching English to Speakers of Other Languages) program.

Findings

Particular types of mentoring which encouraged active participation in scholarly activities through appropriately scaffolded inductions into academia led to increased mentee confidence in terms of making the transition from student to scholar.

Research limitations/implications

The students should not remain assistants on the periphery of academia, but rather play active roles to extend their knowledge and expertise to something that they can attain only with appropriate scaffolding (Vygotsky, 1981). In order to promote such mentorship, it is emphasized that institutional support is indispensable, and that the significance of solid mentorship programs should be re-acknowledged and discussed on an official level.

Originality/value

The study of mentoring within a Japanese context, in particular from the perspectives of sociocultural theory (Vygotsky, 1981) and Bandura's (1994, 1995) self-efficacy theory, is an under-researched area.

Details

International Journal of Mentoring and Coaching in Education, vol. 3 no. 1
Type: Research Article
ISSN: 2046-6854

Keywords

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