• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.2
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• pp.111-118
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• 2020

Recently, bioenergy research using microalgae, one of the most promising biofuel sources, has attracted much attention. Cell disruption, which can be classified as physical or chemical, is essential to extract functional ingredients from microalgae. In this study, we investigated the cell disruption efficiency of Chlorella sp. using low-frequency non-focused ultrasound (LFNFU). This is a continuously physical method that is superior to chemical methods with respect to environmental friendliness and low processing cost. A flat panel photobioreactor was employed to cultivate Chlorella sp. and its growth curve was fitted both with Logistic and Gompertz models. The temporal change in cell reduction by cell disruption using LFNFU was fitted with a Logistic model. The experimental conditions that were investigated were the initial concentration of microalgal cells, relative amplitude of output ultrasound waves, processing volume of microalgal cells, and initial pH value. The optimal conditions for the most efficient cell disruption were determined through the various tests.

• The Korean Journal of Pain
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• v.28 no.3
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• pp.169-176
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• 2015

This review has focused on important but less visible aspects of fibromyalgia (FM) with respect to the high impact of this disorder on patients and societies. FM is a common but challengeable illness. It is characterized by chronic widespread pain, which can be accompanied by other symptoms including fatigue, sleep disturbances, cognitive dysfunction, anxiety and depressive episodes. While our understanding of this debilitating disorder is limited, diagnosis and treatment of this condition is very difficult, even in the hands of experts. Due to the nature of disease, where patients experience invalidation by medical services, their families and societies regarding the recognition and management of disease, direct, indirect and immeasurable costs are considerable. These clinical and economic costs are comparable with other common diseases, such as diabetes, hypertension and osteoarthritis, but the latter usually receives much more attention from healthcare and non-healthcare resources. Present alarming data shows the grave and "iceberg-like" burden of FM despite the benign appearance of this disorder and highlights the urgent need both for greater awareness of the disease among medical services and societies, as well as for more research focused on easily used diagnostic methods and target specific treatment.

• Journal of Technology Innovation
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• v.16 no.2
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• pp.95-123
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• 2008

As a medium for communication on science and technology, science museum could be important to adults who finished formal school education. By analysing all the exhibits at the National Science Museum and conducting a face-to-face interview survey toward 100 adult visitors, based on the PEP / IS model's perspective(Kim, 2007), this study aimed to find a way to induce many adults to visit science museum from the information consumer's viewpoint, not the information provider's one. The result was that most of the exhibits were not related to problems which people focused attention on. About half of visitors, therefore, did not relate their problems with exhibits and responded that there was no relationship between exhibits and their everyday life. However, they had an idea that science and technology could contribute to solving their problems. These findings could suggest that first, science exhibits in relation to people's focused problems or issues are to be developed, second, programs for parents who are accompanied by their children are to be developed, and last, adults' engagement in planning the science museum exhibits is to be considered.

• Journal of Preventive Medicine and Public Health
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• v.40 no.6
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• pp.447-453
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• 2007

Although the New National Health Promotion Plan 2010 target to reduce health inequalities, whether the program will be effective for reducing the health inequalities in Korea remains quite unclear. More and more developed countries have been started to concentrate on comprehensive policies for reducing health inequalities. The health policies of the UK, Netherlands, and Sweden are the most wellknown. I propose that a comprehensive blueprint for tackling health inequalities in Korea should be made and that it must contain five domains: a target, structure and process, life-course approach, area-based approach, and reorganization of health care resources. The target should be based on determinants of health and more attention should be paid to socioeconmic factors. The structure and process require changes from the national health care policy based on medical services to the national health policy that involves the establishment of a Social Deputy?Prime Minister and the strengthening multidisciplinary action. A life-course approach especially focused on the early childhood years. Area-based approach such as the establishment of healthy communities, healthy schools, or healthy work-places which are focused on deprived areas or places is also required. Finally, health care resources should be a greater investment on public resources and strengthening primary care to reduce health inequalities. The policy or intervention studies for tackling health inequalities should be implemented much more in Korea. In addition, it is essential to have political will to encoruage policy action.

• Coupled systems mechanics
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• v.9 no.3
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• pp.289-309
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• 2020

The paper studies the fluid flow profile contained between the orthotropic plate and rigid wall under the action of the moving load on the plate and main attention is focused on the fluid velocity profile in the load moving direction. It is assumed that the plate material is orthotropic one and the fluid is viscous and barotropic compressible. The plane-strain state in the plate and the plane flow of the fluid is considered. The motion of the plate is described by utilizing the exact equations of elastodynamics for anisotropic bodies, however, the flow of the fluid by utilizing the linearized Navier-Stokes equations. For the solution of the corresponding boundary value problem, the moving coordinate system associated with the moving load is introduced, after which the exponential Fourier transformation is employed with respect to the coordinate which indicates the distance of the material points from the moving load. The exact analytical expressions for the Fourier transforms of the sought values are obtained, the originals of which are determined numerically. Presented numerical results and their analyses are focused on the question of how the moving load acting on the face plane of the plate which is not in the contact with the fluid can cause the fluid flow and what type profile has this flow along the thickness direction of the strip filled by the fluid and, finally, how this profile changes ahead and behind with the distance of the moving load.

• Journal of Fashion Business
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• v.16 no.2
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• pp.27-43
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• 2012

Considering the rapid growth of mobile industry and the emerging application marketing, this study focused on fashion applications, which had not drawn much academic attention before, and analysed relevant content composition, information-seeking benefits based on users' lifestyles and resulting differences in satisfaction and loyalty. In short, fashion applications were divided into fashion and non-fashion brand apps. Brand apps were subdivided into luxury, women's wear, men's wear, casual wear, sportswear, accessories and the like. Non-brand apps included commerce, magazine, information, style tip, SNS and wardrobe manager types. As for users' lifestyle-based information search, the higher the tendency to search information on the internet and to favour reasonable consumption, the more basic information on products and brands they sought, whereas the higher the tendency to look for high-profile brands and to favour global culture, the more additional information like images or entertainments they sought. To sum up, given that studies on fashion-specific applications were rare, the present study reviewed and categorized current fashion applications, and suggested theoretical and practical groundwork for developing content based on target consumers' lifestyle and for planning fashion applications in practice.

• Asia-Pacific Journal of Business
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• v.12 no.4
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• pp.253-270
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• 2021

Purpose - The main purpose of this study is to measure and evaluate the level of national liabilities that Korea's national finances can afford. Specifically, the concepts of national debt and national liability are clarified, and the appropriate level of national liabilities is measured in terms of short-term fiscal crisis, mid-to-long-term fiscal crisis, and GDP. Based on these measurements of fiscal crisis, this study would like to propose national fiscal management plans. Design/methodology/approach - In order to clearly recognize the difference between the national debt and the national liability, this study examines the data from 2013 to 2020. In addition, this study uses data from the national financial statements from 2013 to 2018 to measure the appropriate level of national liabilities in terms of fiscal crisis management. Findings - Short-term fiscal crises, measured by current ratios, will not occur. Nevertheless, in view of the cash flow compensation ratio, the short-term bankruptcy of the national finances of Korea depends on the re-borrowing of short-term borrowings and current and long-term borrowings. In addition, in order to manage the mid-to long-term financial crisis, it is necessary to pay attention to the liability growth rate rather than the liability size. Research implications or Originality - While previous studies focused on the appropriate level of national debt, this study was differentiated as a study focused on the level of national liability coverage. It is expected that the results of this study will be used to manage the national fiscal soundness.

• Journal of Information Processing Systems
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• v.20 no.4
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• pp.501-513
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• 2024

In recent years, graph neural networks (GNNs) have been extensively used to analyze graph data across various domains because of their powerful capabilities in learning complex graph-structured data. However, recent research has focused on improving the performance of a single GNN with only two or three layers. This is because stacking layers deeply causes the over-smoothing problem of GNNs, which degrades the performance of GNNs significantly. On the other hand, ensemble methods combine individual weak models to obtain better generalization performance. Among them, gradient boosting is a powerful supervised learning algorithm that adds new weak models in the direction of reducing the errors of the previously created weak models. After repeating this process, gradient boosting combines the weak models to produce a strong model with better performance. Until now, most studies on GNNs have focused on improving the performance of a single GNN. In contrast, improving the performance of GNNs using multiple GNNs has not been studied much yet. In this paper, we propose gradient boosted graph neural networks (GBGNN) that combine multiple shallow GNNs with gradient boosting. We use shallow GNNs as weak models and create new weak models using the proposed gradient boosting-based loss function. Our empirical evaluations on three real-world datasets demonstrate that GBGNN performs much better than a single GNN. Specifically, in our experiments using graph convolutional network (GCN) and graph attention network (GAT) as weak models on the Cora dataset, GBGNN achieves performance improvements of 12.3%p and 6.1%p in node classification accuracy compared to a single GCN and a single GAT, respectively.

• The Journal of the Korea Contents Association
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• v.17 no.4
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• pp.256-266
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• 2017

The purpose of this study is to investigate influencing factors of nursing students' academic stress focusing on dimensions of empathy, ego-resilience, and stress coping strategies. Academic stress, dimensions of empathy, ego-resilience, and stress coping strategies among subjects were collected using structured questionnaires from 305 nursing students between November 1, 2015 and November 30, 2015. The results of this study showed that the factors affecting nursing students' academic stress were grade, personality orientation, major satisfaction, ego-resilience and emotion focused coping style, and the total explanatory power was 54.1%. To improve nursing students' academic stress, it is necessary to pay attention to the nursing students who are in their upper grades, extroverted, and with low major satisfaction. In developing a program to reduce academic stress, it is thought that it is necessary to include measures to raise the level of ego-resilience and to improve the level of emotion focused coping style among stress-coping strategies, and to conduct subsequent research to identify pathways in which the dimensions of empathy, ego-resilience and stress-coping strategies affect academic stress.

• Journal of the Korean Society for Library and Information Science
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• v.50 no.3
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• pp.383-402
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• 2016

The purpose of this study is to study library marketing research trends in Korea and other countries through the analysis of author keyword network of peer-reviewed journal articles. The author keyword was collected from four major LIS journals in Korea and Scopus academic database for other countries'. The data was analyzed using NetMiner4 software. The results of the study were as follows: 1) In Korea, lots of library marketing studies focused on public libraries. However, there was a range of library marketing researches focused on academic libraries in other countries, 2) In Korea, there was not a variety of subjects of library marketing studies and the studies were mainly led by a few scholars, 3) In other countries, many scholars paid attention to digital library marketing through social media and/or web, and 4) there little library marketing studies focused on school libraries both in Korea and other countries.