• Structural Engineering and Mechanics
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• v.48 no.3
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• pp.415-434
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• 2013

This work is concerned with transverse vibrations of axially traveling nanobeams including strain gradient and thermal effects. The strain gradient elasticity theory and the temperature field are taken into consideration. A new higher-order differential equation of motion is derived from the variational principle and the corresponding higher-order non-classical boundary conditions including simple, clamped, cantilevered supports and their higher-order "offspring" are established. Effects of strain gradient nanoscale parameter, temperature change, shape parameter and axial traction on the natural frequencies are presented and discussed through some numerical examples. It is concluded that the factors mentioned above significantly influence the dynamic behaviors of an axially traveling nanobeam. In particular, the strain gradient effect tends to induce higher vibration frequencies as compared to an axially traveling macro beams based on the classical vibration theory without strain gradient effect.

• The Journal of Korea Robotics Society
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• v.18 no.3
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• pp.323-329
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• 2023

This paper discusses the application of collaborative robots to the de-palletizing in IMC (Inte-grated Mail Center). The domestic courier logistics market has grown rapidly, and logistics centers are reaching critical capacity. Therefore, digital innovation based on logistics automation is necessary, and this paper looks at the factors to be considered when introducing collaborative robots and improvement measures considering the characteristics of the de-palletizing task. The benefits of introducing collaborative robots include immediate efficiency and the goal of assisting workers. The paper reviews related research and cases of collaborative robots applied to logistics centers and summarizes the results of collaborative robots introduced to actual postal logistics centers. The paper also provides a comparison of collaborative robots and industrial robots and presents four candidates for collaborative robots for logistics work. The paper also considers suction grippers to be mounted on the arm to grasp the parcel. The paper concludes by discussing the introduction of collaborative robots in the post office logistics center.

• Educational Technology International
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• v.19 no.2
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• pp.229-254
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• 2018

Universities in Korea have driven universities' new attempts to adopt more learner-centered and active learning in English. Problem-based Learning (PBL) is one of the well-known constructive teaching and learning methodologies in higher education. Our research goal was to design and develop the optimal PBL practices for a college physics course taught in English to promote learning and course satisfaction. For four semesters, we have tried and adjusted PBL components, and looked at the trend of the exam scores and group work achievement in each semester. We found that the number of problems and the duration of problem solving are the critical factors that influence the effect of PBL in a college physics course taught in English by going through iterative implementation. The iterative process of applying, designing, and constructing PBL to physics classes was meaningful not only in that we have found the optimal PBL model for learning a college physics course, but also in that we have been reflecting on the continuous interaction with learners during the course.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.6
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• pp.485-494
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• 2020

The study aims to identify and measure factors affecting the salaries of employees in manufacturing enterprises in Hanoi, the important area of Vietnam's economy. We conducted a questionnaire consisting of 31 observation variables with a 5-point Likert scale. Independent variables were measured from 1 "without effect" to 5 "strongly". Based on the literature review and results of interviews, a total of 350 questionnaires were sent to participants; 300 of them met the standards and were subject to be analyzed. The results of Exploratory Factor Analysis (EFA) and Multiple Regression Analysis (MRA) identify six main determinants influencing the salaries of employees in manufacturing enterprises in Hanoi, including Paying views of business leaders (PV), Financial ability of the enterprise (FA), Capacity of workers (CW), Capacity of the contingent of employees engaged in salary work (CC), Role of grassroots trade unions (TU), and State policies and laws on labor - salaries (STL). Based on the findings, some recommendations have been proposed to help the firm leaders design appropriate personnel policies for creating better job satisfactions for employees in the future. On this basis, the authors propose a number of recommendations to improve the salaries of employees in manufacturing enterprises in Hanoi.

• The Research Journal of the Costume Culture
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• v.15 no.6
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• pp.917-928
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• 2007

The purposes of this study were to investigate the hairdo attitude and hairdo involvement importances and differences depending on age. For the experimental work, questionnaires for research are prepared and asked to people who are women living in Seoul and Kyoung-Ki Do. They are collected from September to October 2006. 406 questionnaires are used in the analysis. The collected data were 'analyzed by using SPSS 12.0 software with factor analysis, Cronbach's alpha, paired T-test, and T-test. The results of this study were as follows; To analyze differences in the hairdo attitude and the hair involvement depending on different age groups, two groups were identified: one group of women aged $20{\sim}35$, and the other group of those aged $45{\sim}60$. 1. When the hairdo attitude factors were prioritized, orientations toward 'constancy' and 'consciousness of others' were found to be most critical, followed by those toward 'leader's fashion conformity' and 'distinct individuality'. When the hairdo involvement factors were prioritized, 'interests and pleasure in hairdo' were found to be most important, followed by 'symbolic representation', 'risk awareness', 'coordination of hairdo', and 'fashionableness'. 2. When difference in the hairdo attitude was analyzed, a significant difference was shown in orientations toward 'leader's fashion conformity' and 'consciousness of others'. 3. As for the hairdo involvement of the groups, a significant difference was found only in 'coordination of hairdo', signalling that the younger women put more focus on the coordination.

• Asia-Pacific Journal of Business
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• v.7 no.1
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• pp.11-30
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• 2016

The study specifically aimed to identify factors affecting business longevity. It focused on knowing how embroidery enterprises managed to persist in the industry for many years despite the competitive business environment. After discovering the significant relationships of such factors to longevity, problems experienced by the enterprise cluster were ascertained in order to come up with recommendations that can be proposed to the enterprise owners. Embroidery entrepreneurs have been experiencing a continuous decline in sales due to lack of innovation and intense competition. In the evaluation of their personal entrepreneurial competencies, they scored low on risk-taking, persuasion and networking, and opportunity seeking; thus, implying that these are their weaknesses. On the other hand, the statistical results of this study say that longevity is a function of the entrepreneur's competencies (i.e., persistence, commitment to work contract, demand for quality and efficiency, information seeking, and systematic planning or monitoring), the generation currently managing the business, competition, and the customer's preferences. These results suggest that these independent variables are significant and are deemed critical to business longevity. Thus, entrepreneurs have to find ways on how to use these competencies as an advantage in reinventing their businesses and in reviving their industry.

• Journal of Korean Society of Rural Planning
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• v.22 no.1
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• pp.69-79
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• 2016

The purpose of this study is to draw implications and critical success factors by surveying and analysing practice cases of green care in south Korea. To achieve the object of this study, many valuable cases were checked through preceding researches and internet informations. Case study targets were divided into side-work farmer type, professional farmer type, and Institution directed type, and then case study surveys were performed by each type. Every case has the natural environment in common, and tries to satisfy users's demands and to give the opportunity to communicate. Especially, the strong motivation, mind, and entrepreneurship of operators are very important factors for green care. If the development of government supporting policies and related education programs are accompanied with lots of potential such as Korean oriental medicine, rural tourism village, and sixth industry project, it will be possible to introduce and manage green care successfully.

• Advances in concrete construction
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• v.16 no.4
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• pp.189-203
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• 2023

This study investigates the bending and stability properties of cylindrical constructions, with a focus on their use in the design and implementation of sporting equipment. The work focuses on a cylindrical construction resembling nanomotors, similar to components seen in sports equipment, using mathematical modeling based on high-order beam theory and nonlocal strain gradient theory. The analysis provides important insights into the dynamic behavior of these systems, revealing light on the impact of numerous factors such as rotational velocity, section change rate, and structural dimensions. The results show a relationship between angular velocity growth and section change rate, which leads to an increase in fundamental frequency values. Furthermore, the research emphasizes the effect of structural factors on dynamic deflection, giving critical information for increasing the stability and performance of sporting equipment. This study adds to the area of sports engineering by providing a more nuanced understanding of how cylindrical constructions react under diverse settings. The results will help to guide the design and manufacturing processes of sports equipment, assuring improved stability and performance for players across a wide range of sports.

• Ocean Systems Engineering
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• v.13 no.4
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• pp.367-384
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• 2023

Herein, we present the design and development of an efficient finite element analysis model for thermal plate forming in shipbuilding. Double curvature shells in the ship building industries are primarily formed through the thermal forming technique. Thermal forming involves heating of steel plates using heat sources like oxy-acetylene gas torch, laser, and induction heating, etc. The differential expansion and contraction across the plate thickness cause plastic deformation and bending of plates. Thermal forming is a complex forming technique as the plastic deformation and bending depends on many factors such as peak temperature, heating and cooling rate, depth of heated zone and many other secondary factors. In this work, we develop an efficient finite element analysis model for the thermo-mechanical analysis of thermal forming. Different simulations are reported to study the effect of various parameters affecting the process. Temperature dependent properties are used in the analysis and the finite element analysis model is used to identify the critical flame velocity to avoid recrystallization of plate material. A spring connected plate is modeled for structural analysis using spring elements and that helps in identifying the resultant shapes of various thermal forming patterns. Finally, detailed simulation results are reported to establish the efficacy, applicability and efficiency of the designed and developed finite element analysis model.

• Safety and Health at Work
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• v.15 no.2
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• pp.123-128
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• 2024

Background: Coal miners are highly prone to occupational health risks, such as black lung disease. This study aims to assess the prevalence of black lung disease and the factors associated with black lung disease among coal miners in Asia. Method: This systematic review, conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, searched through the scientific literature of the following databases: EBSCO, ScienceDirect, PubMed, and Scopus. We selected articles that studied black lung disease among coal miners from 48 countries in Asia and were published between 2014 and 2023. Article quality was evaluated using the Critical Appraisal Skills Program. Result: The seven articles that we review studied a total of 653,635 coal miners from various types of coal mines from three countries in Asia. Of these miners, 59,998 experienced black lung disease. Black lung disease is prevalent among 9.18% of coal miners in Asia, which is approximately four times higher than the worldwide prevalence. Common factors that influence black lung disease in Asia include age, years of dust exposure, smoking, drinking, working types, and sizes of mines, type of mines, respiratory functions, spirometry parameters, tenure, lack of attention to occupational health, inefficient surveillance, and weak occupational health service. Conclusion: Although the prevalence of black lung disease among coal miners in Asia is considerably high, it can be addressed through effective prevention measures, monitoring, control, and case reporting.