• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.6
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• pp.603-611
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• 2016

Research and development of mineral-resource-related products has progressed with the increased need to develop mineral resources. The DTH hammer is a resultant product. However, owing to particular work conditions of underground drilling, it is difficult to obtain direct data on the DTH hammer. A DTH drill rig requires a significant amount of money and time for actual testing. This thesis aimed to resolve this problem by using CAE. In a previous paper, the structure of the DTH hammer and its movement were analyzed, and a standard model based on simulation was proposed. Then, experimentation and comparison verification were conducted. In this paper, by using an experimental design method, we derived a control factor of the impact force and efficiency of the DTH hammer and attempted to optimize the design. As a result, the impact energy increased by 14.9%, and the efficiency increased by 3.3%.

• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.127-134
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• 2014

This study was performed to evaluate the effects of sesame oil addition to a tuna oil-enriched emulsion during chlorophyll-photosensitized oxidation. The emulsion principally consisted of tocopherol-stripped canola and tuna oil with or without sesame oil, acetic acid, phospholipids, and xanthan gum. Chlorophyll b was added to promote the production of singlet oxygen upon exposure to light. The oxidation of oil in the emulsion was evaluated by determining the peroxide value (POV) and conjugated dienoic acid (CDA) contents. Concentrations of minor compounds in the emulsion were monitored. Increasing POV and CDA contents in the emulsion were paralleled with decreased docosahexaenoic acid during oxidation, and oxidation was inhibited by the addition of sesame oil. Chlorophyll, polyphenols, tocopherol, and phospholipids were degraded during oxidation of the emulsion; however, their degradation was slowed down by the addition of sesame oil. Lignans in the emulsions containing added sesame oil were barely changed, suggesting that they quenched singlet oxygen physically. Polyphenols were the most effective in improving the stability of tuna oil-enriched emulsions during chlorophyll-photosensitized oxidation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.5
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• pp.1969-1975
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• 2012

The air brake system used in heavy vehicle is very important from the point of safety due to its weight. In general, air brake system generates relatively long response time and large loss of pressure. It is known that the response time can be decreased by optimal design of brake system, i.e., by increasing the system pressure, minimizing the air line, and material of components. In this study, We developed experimental rigs for the measurement of braking response of heavy duty trucks and compared with the simulated results obtained from the net work fluid flow system analysis code (FLOWMASTER). The effect of several parameters such as, system pressure, diameter of pipe, chamber temperature on the brake response performance have been examined.

• Journal of Industrial Convergence
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• v.18 no.1
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• pp.65-71
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• 2020

Recently, the field of using data has begun to attract attention in professional sports. In the field of data utilization, in addition to the classic records obtained within the economy, secondary records that emphasize efficiency are also actively used. Therefore, in this study, we try to study the correlation with the pitcher's strikeout ability through the daily average humidity, which is data outside the competition. For this reason, referring to the daily average record of the area of the home base of 10 teams belonging to the KBO league and the auxiliary stadium, the top 5 in the win, hold, save section to grasp the characteristics of the starting pitcher and the rescue pitcher We analyzed K / 9 records for each person. Through the results of this study, we found a significant difference in the K / 9 record between the starting pitcher and the rescue pitcher, and we can expect to investigate the use of professional sports data and develop the industry in general.

• Korean Journal of Medicinal Crop Science
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• v.23 no.5
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• pp.385-394
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• 2015

Background : Dibenzocyclooctadiene lignans are secondary metabolites present abundantly in the fruits belonging to the genus Schisandra. According to previous studies, Schisandra lignans exhibit anti-inflammatory, anti-cancer and anti-diabetic properties, as well as an inhibitory effect on platelet aggregation. Therefore, establishing the Korean "Omija" (Schisandra chinensis) as a lignan-rich source, in addition to identifying and quantifying the lignans, is extremely valuable. Methods and Results : Dibenzocyclooctadiene lignans were analyzed with liquid chromatography using diode array detection/mass spectrometry, from methanol extracts subsequently identified by a constructed chemical library of 50 lignans. A total of 27 components of lignan including gomisin S were identified, of which schisandrin, gomisin A, gomisin N, deoxyschisandrin, ${\gamma}$-schisandrin, and schisandrin C were identified as the major components in the Korean Omija, Schisandra chinensis. These compounds were divided into two groups, S-biphenyl and R-biphenyl based on the configurations of the stereoisomers structures with contents of 661.7 and 1350.1mg per 100 g dry weight, respectively. The total lignan content averaged 2011.4mg per 100 g dry weight, of which schisandrin and gomisin N comprised the majority (771.8 and 420.5mg per 100 g dry weight respectively). Conclusions : Lignans which are present in high quantities in the ripe fruit of Schisandra chinensis are important functional compounds that play a major role in the prevention and treatment of human diseases.

• Microbiology and Biotechnology Letters
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• v.45 no.1
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• pp.1-11
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• 2017

In this review, we focus on one of the most attractive biomaterials, microfibrillated cellulose (MFC). MFC, a type of nanocellulose, mainly originates from cellulose in lignocellulosic biomass. MFC represents one of incredible important natural resources due to its abundancy, renewability, and sustainability. MFC is produced through mechanical pretreatment, and it is composed of various sizes of microfibers, ranging from a few nanometers to a few micrometers. Because of the heterogenetic compositions of MFC, it possesses superior properties as a material, such as high surface area, high aspect ratio, and peculiar insolubility as a biomaterial. These properties allow MFC to be used in various bio-industries, from the traditional pulp industry to the high-tech food/bio/chemical/medical industries. However, it is difficult to use MFC on a commercial scale owing to the high energy input required during its production and the challenge of controlling its reactivity. Therefore, future studies should be focused on accurately characterizing MFC's surface morphologies, regulating its characteristics in a desirable direction, and standardizing proper guidelines for the analysis of surface morphologies its analysis.

• KIPS Transactions on Software and Data Engineering
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• v.9 no.5
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• pp.161-168
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• 2020

Predicting outcome of the sports enables teams to establish their strategy by analyzing variables that affect overall game flow and wins and losses. Many studies have been conducted on the prediction of the outcome of sports events through statistical techniques and machine learning techniques. Predictive performance is the most important in a game prediction model. However, statistical and machine learning models show different optimal performance depending on the characteristics of the data used for learning. In this paper, we propose a new ensemble model to predict English Premier League soccer games using statistical models and the machine learning models which showed good performance in predicting the results of the soccer games and this model is possible to select a model that performs best when predicting the data even if the data are different. The proposed ensemble model predicts game results by learning the final prediction model with the game prediction results of each single model and the actual game results. Experimental results for the proposed model show higher performance than the single models.

• Journal of Digital Convergence
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• v.18 no.1
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• pp.271-276
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• 2020

This study is intended to compare and analyze the figurative characteristics of game characters focusing on the MMO shooting game 'Battle Ground' and the MOVA game 'League of Legends,' which currently have the largest number of users in Korea, in order to assess how much effect the figurative shape of game characters has on the immersion of players. As a result, the shape of characters from MOVA or MMORPG games with storytelling as an important factor was revealed to have a greater effect on the immersion degree of players than that of the characters from fast-paced shooting games. In particular, it was found that in games where the level of each character is raised as items are added, the height of most characters is the same as their own eight or nine heads, which is longer than ordinary people.

• Journal of the Korean Data and Information Science Society
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• v.28 no.2
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• pp.237-250
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• 2017

A new field of e-sports gains the great popularity in Korea as well as abroad. AOS (aeon of strife) genre games are quickly gaining popularity with gamers from all over the world and the game companies hold game competitions. The e-sports broadcasting teams and webzines use a variety of statistical indicators. In this paper, as an AOS genre game, League of Legends game data is used for statistical analysis using the indicators to predict the outcome. We develop new indicators with the factor analysis to improve existing indicators. Also we consider discriminant function, neural network model, and SVM (support vector machine) for make winning forecasting models. As a result, the new position indicators reflect the nature of the role in the game and winning forecasting models show more than 95 percent accuracy.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.673-676
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• 2017

The Offshore drilling system of domestic drilling systems (drill rigs, drill ship) in Korea is dependent on full imports and the monopolistic situation of a few foreign large corporations is intensifying. In addition, most of domestic technology development tries to develop single product oriented products until now, but it is necessary to develop monitoring control system for package unit commercialization by approaching package development method. Therefore, we will develop a control monitoring system that can integrate the single equipment of the mud system developed previously.