• Journal of Digital Convergence
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• v.19 no.7
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• pp.79-85
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• 2021

After COVID-19, the number of individuals participating in delivery platforms has increased. They are using the participation of the delivery platform as a means of creating a new source of income as well as a means of sports and hobbies. This phenomenon is related to a social phenomenon called 'N-jober'. However, there are still few studies examining this phenomenon. Therefore, this study intends to examine the phenomenon of individual participation in delivery platforms and their issues. Text mining was performed on news data from January 2019, when COVID-19 started. As a result, social issues related to the increase in individual participation in delivery platforms were derived into 5 topics(Introduction to the Phenomenon, Characteristics of Participants, Participant's Income and Fees, Characteristics as a Job, Concern about Potential Risks). This study has significance in that it expanded the perspective of academic discussion on delivery platform business to individual participants.

• Elastomers and Composites
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• v.50 no.3
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• pp.189-195
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• 2015

In this study, we prepared epoxidized poly ethylene-ter-1-decene-ter-divinylbenzene (Epo-PEHV) as a reactive compatibilizer to prevent phase separation phenomenon which occurs upon blending polypropylene (PP) and ethylene-vinyl alcohol copolymer (EVOH). Firstly, PEHV was prepared under high catalyst activity according to content of catalyst and cocatalyst. After then, we modified vinyl group of the terpolymer with epoxy group. We observed that the terpolymer was successfully epoxidized by 1H-NMR and FT-IR analysis. The Epo-PEHV was added by 2, 5, 10% in PP/EVOH blends. The morphologies and mechanical properties of PP/Epo-PEHV/EVOH blends were analyzed by SEM and UTM, respectively. Epo-PEHV enhanced the interfacial adhesion of PP and EVOH blends.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.2
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• pp.102-114
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• 2021

NDF (No Defect Found) is a phenomenon in which defects have been found in the manufacturing, operation and use of a product or facility, but phenomenon of defects is not reproduced in the subsequent investigation system or the cause of the defects cannot be identified. Recently, with the development of the fourth industrial revolution, convergence of hardware and software technologies in various fields is spreading to products such as aircraft, home appliances, and mobile devices, and the number of parts is increasing due to functional convergence. The application of such convergence technologies and the increase in the number of parts are major factors that lead to an increase in NDF phenomena. NDF phenomena have a significant negative impact on cost, reliability, and reliability for both manufacturers, service providers and operators. On the other hand, due to the nature of NDF phenomena such as difficult and intermittent cause identification and ambiguity in judgment, it is common to underestimate the cost of NDF or fail to take appropriate countermeasures in corporate management. Therefore, in this paper, we propose a methodology for estimating NDF costs by the PAF model which is a quality cost analysis model and ABC (Activity Based Costing) technique. The methodology of this study suggests a detailed procedure and the concept to accurately estimate the NDF costs, using ABC analysis, accounting system information, and IT system data. In addition case studies have validated the methodology. We think this could be a valid methodology to refer to when estimating the cost of other parts. And, it is meaningful to provide important judgment information in the decision-making process based on quality management and ultimately reduce NDF costs by visualizing them separately by major variable factors.

• Journal of the Korea Institute of Military Science and Technology
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• v.27 no.1
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• pp.1-7
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• 2024

Weather is one of the main causes of aircraft accidents, and among the phenomena caused by weather, icing is a phenomenon in which an ice layer is formed when an object exposed to an atmosphere below a freezing temperature collides with supercooled water droplets. If this phenomenon occurs in the rotor blades, it causes defects such as severe vibration in the airframe and eventually leads to loss of control and an accident. Therefore, it is necessary to foresee the icing situation so that it can ascend and descend at an altitude without a freezing point. In this study, vibration data in normal and faulty conditions was acquired, data features were extracted, and vibration was predicted through deep learning-based algorithms such as CNN, LSTM, CNN-LSTM, Transformer, and TCN, and performance was compared to evaluate blade icing. A method for minimizing operating loss is suggested.

• Journal of the Korea Convergence Society
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• v.8 no.8
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• pp.267-281
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• 2017

Despite the recent importance of interdisciplinary convergence research, little has been studied on the detailed experience while conducting convergence research in Korea. To deeper understand challenges and overcoming in convergence research and to suggest an administrative system for it, by analyzing researchers experience and cognition while conducting their actual convergence research, in-depth interviews with 16 full-time faculty members with expertise in convergence research and research administration in a university and analyzed the interviews by using the paradigm model of grounded theory. The results show that the core phenomenon researchers experienced is that "convergence research is not being effectively conducted," and they experience growth in research through pursuing efforts and improving research atmosphere in various aspects. Based on these findings, we made several suggestions for promoting convergence research.

• Management & Information Systems Review
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• v.2
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• pp.75-93
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• 1998

In this paper, we propose a new algorithm(N_BP) to be capable of overcoming limitations of the traditional backpropagation(O_BP). The N_BP is based on the method of conjugate gradients and calculates learning parameters through the line search which may be characterized by order statistics and golden section. Experimental results showed that the N_BP was definitely superior to the O_BP with and without a stochastic term in terms of accuracy and rate of convergence and might surmount the problem of local minima. Furthermore, they confirmed us that the stagnant phenomenon of learning in the O_BP resulted from the limitations of its algorithm in itself and that unessential approaches would never cured it of this phenomenon.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.107-112
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• 1998

In this paper, we propose a new paradigm (NEW_BP) to be capable of overcoming limitations of the traditional backpropagation(OLD_BP). NEW_BP is based on the method of conjugate gradients with the normalized direction vectors and computes step size through the linear search which may be characterized by order statistics and golden section. Simulation results showed that NEW_BP was definitely superior to both the stochastic OLD_BP and the deterministic OLD_BP in terms of accuracy and rate of convergence and might sumount the problem of local minima. Furthermore, they confirmed us that stagnant phenomenon of training in OLD_BP resulted from the limitations of its algorithm in itself and that unessential approaches would never cured it of this phenomenon.

• Structural Engineering and Mechanics
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• v.5 no.4
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• pp.369-383
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• 1997

The classical theory of thin-walled members is unable to reflect the shear lag phenomenon since it is based on the assumption of no shearing strains in the middle surface of the walls. In this paper, an energy equation for the lateral buckling of thin-walled members has been derived which includes the effects of torsion, warping and, especially, the shearing strains which reflect the shear lag phenomenon. A numerical analysis for the lateral buckling of thin-walled members with openings by using Galerkin's method of weighted residuals has been presented. The proposed numerical values and the predictions by experiment for the lateral buckling loads are to agree closely in the paper. The results from these comparisons show that the proposed method here is capable of predicting the lateral buckling of thin-walled members with openings. The fast convergence of the results indicates the numerical stability of the method. By the study, a very complex practical eigenvalue problem is transformed into a very simple one of solving only a linear equation with one variable.

• Journal of Wellbeing Management and Applied Psychology
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• v.3 no.1
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• pp.11-20
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• 2020

Anecdotal reports indicate that maladaptive patterns of Internet use constitute behavioral addiction. Internet addiction is characterized by unrestrained and awfully controlled engrossment or behaviors regarding internet access that lead to impairment, stress, dimensionally measured depression, indicators of social separation and anguish. By reviewing and analyzing approximately 100 articles we present evidence that are able to provide an overview of the main themes and proclivity covered by existing and relevant studies. The vital detection of this research unveils that many factors related to social, demographic, lifestyle changes related constructs have a bearing on the phenomenon of internet addiction strongly. This study not only reached certain conclusions for both theory and practice, but also defined future lines of research according to the gaps detected by the study's results. The main findings from this literature, though not conclusive, but will help the researcher and policymakers to obtain a better understanding and description of the problem faced by the youth and necessary to develop some remedies to lessen the addiction phenomenon.

• Journal of Industrial Convergence
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• v.13 no.1
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• pp.25-40
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• 2015

The aim of this study is to a study on the effects of fertile women on the low fertility in Korea. It is designed to research a model and established hypothesis with emphasis on major variables based on theoretical discussions. However, the result of the study is as follows. Firstly, this brought in delivery avoid phenomenon thus resulting in lower delivery phenomenon. The government should propose reasonable solutions to persuade female personal value and important elements of delivery rate at the same time. Secondly, Patriarchal stereotypes weighting household labor to female traditionally pressures working female with double burden as dual stance of work and family worsen the delivery will. Such atmosphere within a family generates female with an ability to get pregnancy to avoid marriage and delivery. Lastly, the research has pointed out the delivery support policy as most ineffective policy among government policies. To solve this problem, the government policy to recover delivery rate must be reviewed continuously and to be exercised immediately.