• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.2
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• pp.60-71
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• 2022

The reusable, low-cost launch vehicle development trend in the recent launch vehicle market is being subdivided into several ways, and the throttleable engine is one of them. Plus, several nations have selected methane as a next-generation propellant due to its cleanness. In this research, a throttleable pintle injector using gas methane and liquid oxygen as propellants was developed, followed by its spray and combustion characteristics analysis, including high pressure cold and hot tests. The designed throttleable pintle injector has a double sleeve structure, and its tightness and functionality are confirmed through repetitive atmospheric, high-pressure cold tests, and hot tests. Though some design errors were discovered and a low throttling level was unable to be achieved in the combustion test.

• Journal of Platform Technology
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• v.11 no.3
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• pp.12-23
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• 2023

In the 2020s, the K-Pop market has been dominated by girl groups over boy groups and the fourth generation over the third generation. This paper presents methods and results on lyric clustering to investigate whether the generation of girl groups has started to change. We collected meta-information data for 1469 songs of 47 groups released from 2013 to 2022 and classified them into lyric information and non-lyric meta-information and quantified them respectively. The lyrics information was preprocessed by applying word-translation frequency vectorization based on previous studies and then selecting only the top vector values. Non-lyric meta-information was preprocessed and applied with One-Hot Encoding to reduce the bias of using only lyric information and show better clustering results. The clustering performance on the preprocessed data is 129%, 45% higher for Spherical K-Means' Silhouette Score and Calinski-Harabasz Score, respectively, compared to Hierarchical Clustering. This paper is expected to contribute to the study of Korean popular song development and girl group lyrics analysis and clustering.

• Trans-
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• v.13
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• pp.1-16
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• 2022

Recently, the method of contacting and purchasing NFT art has been popularly evolving, and various prospects and predictions for NFT art have emerged. The discussion of NFT art is mainly a hot topic in terms of market size, profit, and sustainability. As the transition to digital accelerated after COVID-19, almost all genres of culture and arts faced a forced transition with the topic of combining digital and technology, but in terms of profitability, it was generally difficult to guarantee positive continuity. On the other hand, the combination of art and blockchain, and the new distribution method called NFT, attracted a lot of attention by causing fundamental changes that lead to technological transformation, continuity through profit creation, and even genre expansion of visual art. The discourse on NFT and the art market is a recent phenomenon and is being discussed focusing on statistics and numerical reports through data from newspapers and art-related research institutes rather than academic analysis or research. However, discussions related to NFT art should be considered in various aspects, such as the incorporation of technology and art, changes in distribution methods, and changes in creative methods according to media changes, not just short stories of phenomena such as high prices and winning bids. In this paper, we would like to examine the impact of changes in creators and distribution methods.

• The Journal of the Korea Contents Association
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• v.16 no.6
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• pp.123-134
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• 2016

As the internet of things has come into the spotlight, wearable devices have been emerging as a new and growing market and the next hot thing in the world. However, wearable device growth in the market has not met expectations. For continued growth and diffusion of wearable devices, it is important to investigate user resistance factors to them. This study gives attention to people who have resistance to wearable devices' tendency towards innovative uses. Specifically, this study is intended to find out which factors influence consumers' resistance and intention to use wrist-worn wearable devices, which are in high demand among wearable device. Results of the study show that the relative advantage, innovation expectation, complexity, financial risk and physical risk are the predictors of innovation resistance on wrist-worn wearable devices. And consumers' resistance affects the intention of positive acceptance. These findings confirm the importance of consumer resistance to the wrist-worn wearable device.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.5
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• pp.671-677
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• 2007

This study examined the relationship between chlorophyll(Chl) and ascorbic acid(ASA) as an index of freshness for vegetables, when the general consumers purchase several kinds of vegetables at the market. The leaves and fruits of several types of vegetables were divided into top, middle, and basal sections. Chl was determined by a spectrophotometer, and ASA was analyzed by high-performance liquid chromatography. For the vegetable sections, we found that Chl and ASA levels were highest in the top sections, followed by the middle, and were lowest in the basal portions. For the relationship between Chl and ASA in vegetables, there were seven classifications including high Chl(above 80mg/100g of fresh weight) and high ASA(above 80 mg/100 g of fresh weight) for mallow, and kail; the second group had high Chl and low ASA(below 80 mg), such as in spinach, burdock, and perilla leaves; the third group contained medium Chl($40{\sim}80mg$) and medium ASA($40{\sim}80mg$) levels, such as for gonddalbee, angelica, pumpkin leaf and coriander; the fourth group had medium Chl and low ASA levels, as in crown daisy and lettuce; the fifth group contained low Chl(below 40 mg) and high ASA, such as in hot peppers and parsley; the sixth group had low Chl and medium ASA levels, and included broccoli, pak choi, and sweet peppers; finally the seventh group contained low Chl and low ASA levels, as in dropwort, young radishes, shallots, cucumbers and swiss chard.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.5
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• pp.661-670
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• 2007

To investigate the market potential for developing Gochujang(a traditional Korean hot pepper soybean paste) products in the UK including the European market, a qualitative consumer study utilizing focus groups was conducted on the $23rd{\sim}25^{th}$ of May, 2005. The focus group approach utilizes small groups of consumers and is very effective in determining the ways in which a product can be used, by examining consumer perceptions on the overall sensory properties of a product as well as variations in taste, flavour, and texture. A series of six consumer group studies were carried out in three different locations around the UK. Each group involved approximately eight respondents(a total of 48 respondents) and ran for at least 90 minutes. The respondents were recruited by specific criteria to achieve a cross-section of ages and genders. All respondents purchased, prepared, and ate home-cooked Oriental/Far Eastern cuisine. Consumer reactions to Gochujang in its traditional form, and in manufactured products, were explored in terms of appearance, texture, flavour, and taste the consumers' perceived uses and applications for products were also examined. Many consumers were familiar with ethnic cuisines such as Chinese, Thai, Japanese, Indian, and Tex/Mex, already preparing these foods using various convenience products at home at least twice a week. However, Korean cuisine was not mentioned by any of the respondents. The Gochujang sauce presented during the interview had broad based appeal mainly as a dipping sauce, and to a lesser degree as a marinade. Traditional Gochujang has the potential to inspire consumers who are looking for novel and authentic world cuisine products. From the sensory evaluations of various prototypes developed according to consumer reactions during the focus group interviews, three prototypes(a sauce for chicken, dipping sauce type, and BBQ sauce type) were determined for further consumer preference studies.

• Agribusiness and Information Management
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• v.4 no.1
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• pp.24-31
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• 2012

This case study investigates the KIKO currency option that has been a social issue in recent years among developing countries, especially Korea, where the financial derivatives market is in a state of rapid growth. The forward transaction which becomes a basis of derivatives is intended to hedge risks that may be caused by a future change in asset prices. Although it originates from a simple form of agricultural transactions, there currently exists a variety of derivatives in more sophisticated forms. In the Korean agricultural industry, the need to use such derivatives is great, as there is a huge risk of price fluctuation in agricultural products due to frequent adverse weather. In addition, many developing countries with export-led industrial structures similar to Korea's, of necessity must resort to currency hedging as a method of reducing relevant risk. However, in most cases, the lack of understanding about financial derivatives results in an inappropriate application of these derivatives. The KIKO in this study represents such cases. Since 2007, KIKO has been sold in Korea to many small- and medium-sized export companies for the purpose of currency hedging when the exchange rate between the Korean won and the U.S. dollar was in a downward spiral. The main focus of this study is a case which is most representative of KIKO. As inflation rapidly increased during the financial crisis in the U.S. at the end of 2007, derivatives became a hot issue in the courts rather than in the financial markets. This case study investigates what KIKO and the fierce legal debates over it imply, from the perspective of the option of value evaluation in order to suggest not only a direction in which companies can utilize financial derivatives, but also a roadmap for the future derivatives market.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.11
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• pp.2181-2186
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• 2016

Recently, the drone industry rapidly rises to the surface as the new market leading the future, and it seems that the hot UAV drone market shows the similar trend to that of the smartphone. It is expected that the individual application of the drone is quickly diffused as the smartphone roles of camera and game player with the communication medium. For example, the drone is developed mainly as war weapons, but now it is getting close to our real life as the toy or tool for the aerial photography. In this paper, we studied the education for how to bring the aging population to the drone industry. Previously, the controlling skill and taking aerial photography seemed to have nothing to do with citizen seniors. However, we develop the education for try to show any positive relationship between those, in this paper, thus creating more job opportunities for them.

• Journal of Marine Bioscience and Biotechnology
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• v.12 no.2
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• pp.108-114
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• 2020

A variety of shellfish species sold for human consumption are available for purchase in the domestic fish market. The microalgae families inhabit the ocean, where planktons supply the main nutritional resource for the growth of shellfish. Some phytoplanktons produce toxic compounds that are accumulated in shellfish and ultimately cause toxicity in humans. This article reports the cytotoxicity of commercially available shellfish species. Accordingly, hot water extract (HWE) and an aqueous fraction of 50% methanol extract (MEE-AF) showed no significant cytotoxicity on the two cell lines (i.e., HL-60 and Vero cell lines), but 50% methanol extract (MEE) in 3, 6 samples showed 50% cytotoxic effects on HL-60 cells, and 1, 4 samples showed 40%, 20% cytotoxic effects on Vero cells, respectively. In addition, their consequential dichloromethane fractions (MEE-DF) exhibited significant toxicities at the highest concentration (1,000 ㎍/ml) on HL-60 and Vero cells. Since the shellfish samples showed cytotoxicity in the dichloromethane fraction, it is possible that the dichloromethane fraction contains marine toxins. Further research will be needed to identify the toxic components from each sample.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.137-145
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• 2022

This study attempted to examine the subjectivity of consumers of the MZ generation in their 20s on health functional foods, which have recently emerged as hot consumption items. A study was conducted using the Q methodology to examine the characteristics, meanings, and values of the younger generation in the health functional food market represented by red ginseng, vitamins, and probiotics. Using the QUANL analysis program, a total of 37 Q samples and 30 P samples were used in the study, and three types with unique tendencies were found. The first type discovered through this was named "YubiMuhwan(Forewarned, forearmed; 有備無患)", the second type was "Bansinbanui(half confident; 半信半疑)", and the third type was called "Silsagushi(empirical tradition; 實事求是)". Reflecting these attributes, various strategic ideas were presented for the classification of new characteristics and consumers in the health functional food market and promotion of sales.