• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.4
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• pp.275-282
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• 2017

In this paper, using a pattern transformation triggered by deformation, we propose a porous structure that exhibits the characteristic of negative Poisson's ratio in both tension and compression. Due to the lack of torque for rotational motion of ligaments, the existing porous structure of circular holes shows positive Poisson's ratio under tension loading. Also, the porous structure of elliptic holes has a drawback of low durability due to stress concentration. Thus, we design curved ligaments to increase the rotational torque under tension and to alleviate the stress concentration such that strain energy is uniformly distributed in the whole structure. The developed structure possesses better stiffness and durability than the existing structures. It also exhibits the negative Poisson ratio in both compression and tension of 10% nominal strain. Through nonlinear finite element analysis, the performance of developed structure is compared with the existing structure of elliptic holes. The developed structure turns out to be significantly improved in terms of stiffness and durability.

• Journal of Digital Convergence
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• v.14 no.7
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• pp.339-345
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• 2016

While a game market has been growing consistently world widely, a market of arcade or video game has been detained. In this stagnation, the latest one in 2015, "Super Mario Maker" of Mario series that's been running in good for 30 years, the notable sale and growth of which are extraordinary. As for a study in customizing, a literature of game customizing and studies that are foregone were mostly handling contents about a game character. In the survey that's done in this thesis about knowledge and needs in customizinge game users have, it was shown they want to customize sides of a rule and a character. I analyzed what the main factors are in this game which uses a main concept of customizing and the reason for high profits and popularity. As a result of the analysis, four features, possibility to customize a game rule, share data among users, collaboration in marketing with NFC figure characters, offering updates with sustained and new customizing features were found out. I am certain a game customizing will be helping to meet users and be used for various industries without limit of existing character.

• Journal of Digital Convergence
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• v.18 no.4
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• pp.137-148
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• 2020

While the diversity of consumer choices due to the increased information in the digital age is positive, there are also many problems with the information overload. There are even situations in which consumers can not make the best choices under the weight of information. The purpose of this study is to look at how information overload plays a role in influencing online consumer behavior. With factors related to characteristics of the shopping mall, the recognition of the mall, the quality of the mall, the composition of the shopping mall, and the purchase recommendation service were set to analyze how these variables change the behavior of online consumers when information overload appears. According to the analysis results, all of characteristic factors of shopping malls set up in this paper are analyzed to have a constant effect on the behavior of online consumers, and information overload also has a constant medium effect on the recognition of shopping malls, the quality and the structure of shopping malls, and the provision of purchase recommendation services. And characteristic factors of shopping malls are also showing positive effects on online consumer behavior in information overload situations.

• Journal of Digital Convergence
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• v.17 no.11
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• pp.557-567
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• 2019

This investigation was conducted to derive future recognition and future competency of career counselors using future workshops and to verify the effectiveness of improving future adaptability. For this purpose, the future workshop was conducted for 25 career counselors and the data written and the discussion contents of the future workshop were analyzed. For analysis, word frequency analysis and corresponding sample T-verification were conducted, and the main words were derived through consensus. The results, First, the keywords of future recognition showed high frequency of robot, artificial intelligence, leisure, education, convenience, and the disabled. Second, the future labor sites projected the most changes due to high technology. Third, at the career counseling site, professional career counselors and robot counselors related to the fourth industrial revolution are expected to appear. Fourth, future competencies of career counselors were derived from information processing ability, professional counseling ability, communication ability, and ethical consciousness. Finally, it was confirmed that the future adaptability of career counselors increases after participating in future workshops, and the future competencies derived from this study are expected to be used for job training of career counselors.

• Journal of Ginseng Research
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• v.45 no.5
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• pp.583-590
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• 2021

Background: Gintonin, isolated from ginseng, acts as a ginseng-derived lysophosphatidic acid (LPA) receptor ligand and elicits the [Ca²⁺]_i transient through six LPA receptor subtypes (LPARSs). However, the long-term effects of gintonin-enriched fraction (GEF) on the gene expression of six LPARSs remain unknown. We examined changes in the gene expression of six LPA receptors in the mouse whole brain, heart, lungs, liver, kidneys, spleen, small intestine, colon, and testis after long-term oral GEF administration. Methods: C57BL/6 mice were divided into two groups: control vehicle and GEF (100 mg/kg, p.o.). After 21-day saline or GEF treatment, total RNA was extracted from nine mouse organs. Quantitative-real-time PCR (qRT-PCR) and western blot were performed to quantify changes in the gene and protein expression of the six LPARSs, respectively. Results: qRT-PCR analysis before GEF treatment revealed that the LPA6 RS was predominant in all organs except the small intestine. The LPA2 RS was most abundant in the small intestine. Long-term GEF administration differentially regulated the six LPARSs. Upon GEF treatment, the LPA6 RS significantly increased in the liver, small intestine, colon, and testis but decreased in the whole brain, heart, lungs, and kidneys. Western blot analysis of the LPA6 RS confirmed the differential effects of GEF on LPA6 receptor protein levels in the whole brain, liver, small intestine, and testis. Conclusion: The LPA6 receptor was predominantly expressed in all nine organs examined; long-term oral GEF administration differentially regulated LPA3, LPA4, and LPA6 receptors in the whole brain, heart, lungs, liver, kidneys, small intestine, and testis.

• Journal of Digital Convergence
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• v.17 no.3
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• pp.107-117
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• 2019

In the era of SNS, many people relies on it to express their emotions about various kinds of products and services. Therefore, for the companies eagerly seeking to investigate how their products and services are perceived in the market, emotion mining tasks using dataset from SNSs become important much more than ever. Basically, emotion mining is a branch of sentiment analysis which is based on BOW (bag-of-words) and TF-IDF. However, there are few studies on the emotion mining which adopt feature selection (FS) methods to look for optimal set of features ensuring better results. In this sense, this study aims to propose FS methods to conduct emotion mining tasks more effectively with better outcomes. This study uses Twitter and SemEval2007 dataset for the sake of emotion mining experiments. We applied three FS methods such as CFS (Correlation based FS), IG (Information Gain), and ReliefF. Emotion mining results were obtained from applying the selected features to nine classifiers. When applying DT (decision tree) to Tweet dataset, accuracy increases with CFS, IG, and ReliefF methods. When applying LR (logistic regression) to SemEval2007 dataset, accuracy increases with ReliefF method.

• Journal of Industrial Convergence
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• v.17 no.2
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• pp.9-14
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• 2019

This study was carried out to investigate how the basic plan of the Saemangeum development project that has been developed by the government since 1991 has been changed and to present a new development strategy by analyzing the future value and tourism resource value of Saemangeum development. The research methodology is based on the in - depth analysis methodology of the time series research materials and press releases published by the Saemangeum Development Administration, which oversees the development of Saemangeum. The government announced a plan to significantly reduce agricultural land and increase the proportion of non-agricultural land to 70% in order to create a multifunctional complex. After that, the government revised the basic plan of Saemangeum in 2014 and changed the plan to tailor the investment demand in order to cultivate investment demand, and introduced the special economic cooperation system for global economic cooperation. Therefore, the purpose of this paper is to analyze the process of Saemangeum development to date and to evaluate the value of Saemangeum development as a tourism resource, centered on the Master Plan of the Saemangeum Development Project changed by the government. Based on the results of this analysis, I would like to present the vision of Saemangeum tourism development considering Saemangeum 's environment and characteristics of the surrounding scenery by referring to trends and similar cases of international tourism.

• Journal of Industrial Convergence
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• v.17 no.2
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• pp.29-34
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• 2019

The purpose of this study is to analyze the achievements of employment support by the government support specialization project. The data used in this study are based on the comparison of 5 - year employment support field and the operation results of the program until 2014-2018. The results of the study are as follows. First, the overall employment rate of the university has been continuously increased. Especially, the employment rate of the specialization department has been higher than the employment rate of the non - specialization department. Second, as a result of the analysis of the employment capacity strengthening index and the learning capacity strengthening index, it showed a steady increase in each year and contributed to the cultivation of customized talents required by the local society and the national industry. Third, as a result of analyzing the satisfaction of students who are business users, it was confirmed that the business reflecting the demands of the consumers was realized. Fourth, the continuous improvement of the business and the reflux have made the infrastructure of the employment support project more advanced and the system of supporting employment of the university systematically established. In conclusion, the result of the employment support project according to the specialization program showed excellent results and it is necessary to complement theses results when establishing related business plan in the future.

• The Journal of the Acoustical Society of Korea
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• v.38 no.1
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• pp.30-38
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• 2019

In recent years, researches on various communication methods have been conducted, particularly on OFDM (Orthogonal Frequency Division Multiplexing) and CDMA (Code Division Multiple Access) methods, as the use of underwater communication increases. While OFDM is, in general, advantageous in that it is resistant to Doppler in the water and it enables a high-speed communication, CDMA is resistant to frequency selective fading in the water and it can reduce energy consumption. Therefore, in this paper, we performed experiments in the shallow water in Western Sea of Korea to analyze the performance of OFDM and CDMA communication systems in the underwater channel environment. The maximum delay spread and Doppler spread were drawn by using the data obtained from the real sea area in order to analyze the underwater channel environment characteristics of the shallow water in Western Sea of Korea. The communication performances of OFDM and CDMA are shown as coded BER (Bit Error Rate) according to the variation of the maximum delay spread and the Doppler spread, respectively. The result of the analysis show that the OFDM method has more resistant performances to the underwater channel environment changes than the CDMA method.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.6
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• pp.446-457
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• 2020

Crescentic sand bar in the coastal zone of eastern Korea is a common morphological feature and the rhythmic patterns exist constantly except for high wave energy events. However, four consecutive typhoons that directly and indirectly affected the East Sea of Korea from September to October in 2019 impacted the formation of longshore uniform sand bar and overall shoreline retreats (approx. 2 m) although repetitive erosion and accretion patterns exist near the shoreline. Widely used XBeach to predict storm erosions in the beach is utilized to investigate the morphological response to a series of storms and each storm impact (NE-E wave incidence). Several calibration processes for improved XBeach modeling are conducted by recently reported calibration methods and the optimal calibration set obtained is applied to the numerical simulation. Using observed wave, tide, and pre & post-storm bathymetries data with optimal calibration set for XBeach input, XBeach successfully reproduces erosion and accretion patterns near MSL (BSS = 0.77 (Erosion profile), 0.87 (Accretion profile)) and observed the formation of the longshore uniform sandbar. As a result of analysis of simulated total sediment transport vectors and bed level changes at each storm peak Hs, the incident wave direction contributes considerable impact to the behavior of crescentic sandbar. Moreover, not only the wave height but also storm duration affects the magnitude of the sediment transport. However, model results suggest that additional calibration processes are needed to predict the exact crest position of bar and bed level changes across the inner surfzone.