• Proceedings of the KWS Conference
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• 2009.11a
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• pp.21-21
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• 2009

현장의 GMA 용접기는 일반적으로 용접기 본체로부터 와이어 송급장치까지의 거리가 약 50m 정도 떨어져 있고 송급장치로부터 토치까지의 거리는 약 3~5m 정도이다. 특히 국산 GMA 용접기의 와이어 송급장치는 DC 모터의 일종인 프린트모터를 사용하고 있으며 제어기는 오픈루프 제어를 하고 있다. 따라서 와이어 송급속도의 변동을 보상할 수 있는 어떤 수단도 장착되어 있지 않다. 또한 송급장치와 토치간 와이어를 안내하는 케이블 도관의 마찰 때문에 토치 끝단에서의 와이어 송급속도가 불규칙해질 수밖에 없다. 용접 시 와이어 송급속도의 순간적인 변동 때문에 용접부의 전류 파형이 매우 불규칙해지고 이 때문에 용융된 용적이 용융풀로 이행하지 못하고 스패터로 비산하는 현상을 발생시킨다. 본 연구에서는 이를 해결하고자 국산 SCR 용접기 및 인버터 용접기와 호환 가능한 디지털 제어형 와이어 송급장치와 Push-Pull 용접 토치를 개발하였다. 또한, 개발된 시스템을 이용하여 정 역 방향 제어기술을 적용하였고 아크 발생 시의 스패터 최소화 공정을 제안하였다. 실험은 SM490A 강재를 사용하여 BOP(Bead On Plate) 용접을 실행하였다. 용접 중 LabVIEW를 이용하여 아크 발생 초기 전류, 전압 그리고 와이어 송급속도를 측정하였고, 고속 카메라를 이용하여 용접현상을 분석하였다. 본 연구를 통해 아크 발생 초기의 스패터를 최소화하는 공정을 도출할 수 있었다. 용접공정 변수인 아크 발생 초기의 와이어 송급속도, 와이어의 역송급 진행거리 그리고 역송급 판단 시점의 용접 전류 값은 실험을 통해 얻을 수 있었다. 또한, 이 연구를 통해 개발된 시스템의 성능을 평가하였다.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.158-164
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• 2017

암을 억제시키는 기능을 하는 단백질로 잘 알려진 p53은, 주로 종양세포에서 과도하게 발현되는 단백질인 HDM2와 복합체를 형성하여 비활성화되고 항암기능을 상실하게 됩니다. 때문에 종양세포에서의 p53-HDM2의 상호작용을 억제하기 위해 현재까지 많은 연구가 진행되어왔으며, 다양한 p53-HDM2 억제제가 개발된 바 있습니다. 최근 연구들에 따르면, HDM2와 결합친화도를 높이고 소수성 작용(hydrophobic interaction)에 기여하여 보다 안정한 구조를 만드는 탄화수소체인(staple)을 연결시킨 펩타이드 설계에 대한 관심이 높아지고 있는 추세입니다. 이에, 본 연구에서는 분자동역학 모의실험을 통해서 얻은 탄화수소체인-p53과 비탄화수소체인-p53 및 각각의 HDM2와 결합한 복합체를 기반으로 EDISON의 용매화 자유에너지(Solvation Free Energy) 프로그램을 이용하여 탄화수소체인의 특징 및 역할을 구조적인 측면과 열역학적인 측면으로 분석하여 비교하고자 합니다. 우리 연구에서 비탄화수소체인-p53의 구조는 분자동역학 시뮬레이션을 수행하는 동안 나선구조형태로 풀려 HDM2와 결합 유도 시에 주요결합 아미노산 잔기가 올바른 결합부위와 상호작용하지 못한 결과를 확인한 반면, 탄화수소체인이 형성된 구조는 시뮬레이션 동안에도 펩타이드의 나선구조를 유지시켜 HDM2와 주요 결합을 형성하는 아미노산 잔기들을 올바른 방향으로 배치시켜 HDM2와의 결합친화도를 높였습니다. 이 연구 결과는 탄화수소체인이 펩타이드의 나선성을 유지시키고, HDM2와의 상호작용을 통한 구조적인 안정성 유도 및 용매화 자유에너지에 큰 기여를 통해 p53-HDM2상호작용 억제제에서 긍정적인 역할을 할 가능성을 보여줍니다.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.617-625
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• 2006

This study was done to provide basic data for the operation of a safer cook-chill system by comparing and evaluating the quality of foods which were prepared using the sous vide cook-chill system and the conventional cook-chill system, according to the preparation methods and storage temperature. Simmered chickens in soy sauce were prepared using the sous vide cook-chill system and the conventional cook-chill system and their quality was evaluated at the time of preparation and storage. Firstly, foods were prepared using the sous vide cook-chill (SVCC) system and the conventional cook-chill (CC) system and the redquired time and temperature during each preparation stage were measured and physicochemical (pH, Aw, and moisture content) and microbial qualities were evaluated. Secondly, in order to evaluate the quality and safety, the moisture content and microbial (standard plate count, coliform count, psychrotrophic bacteria count, and anaerobic bacteria count) qualities were evaluated according to the preparation methods and temperatures after the foods were stored at 3$^{\circ}C$ and 10$^{\circ}C$ for 10 days and reheated.

• Korean Journal of Animal Reproduction
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• v.24 no.3
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• pp.225-230
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• 2000

This study was designed to investigate effect of cryoprotectant kinds and cell stages on the viability of bovine embryos cryopreserved by vitrification. The oocytes were collected from ovarian follicles of Korean native cows. The follicular oocytes were cultured in TCM-199 medium containing hormone and 10%(v/v) FCS for 24~48hrs in a incubator with 5% $CO_2$, in air at 38.5$^{\circ}C$ and then matured oocytes were again cultured for 7~10 hrs with spermatozoa capacitated by preincubation. The vitrification solutions of EFS and EDS were consisted of 40%(v/v) ethylene glycol, 18%(v/v) Ficoll and 0.3M sucrose, and 20%(v/v) ethylene glycol, 16.5%(v/v) DMSO and 0.5M sucrose in TCM-199 medium supplemented with 10% FCS, respectively. The embryos were exposed to EFS or EDS at $25^{\circ}C$ and loaded into OPP straw for 30 sec. The plug end of each straws was heat-sealed and straws was slowly immersed into liquid nitrogen(L$N_2$). The results obtained were summarized as follows : 1 . The rates of cleavage and hatching of embryos frozen with vitrification, rapid and slow freezing methods were 67.5%, 27.5% and 42.5%, 20.0% and 52.5%, 25.0%, respectively And rates of cleavage and hatching of embryos frozen with vitrification method were significantly(p<0.05) higher than those in other methods, and the rates were lower than those in control group(82.5% and 37.5%). 2. The rates of cleavage and hatching of embryos were significantly(p<0.05) different between EFS(47.5% and 22.5%) and EPS(52.5% and 27.5%), and the rates were lower than those in control group(82.5% and 37.5%). 3. After vitrification freezing of bovine embryos at zygote, 2 cell, 8 cell, morulae and blastocyst stage, the rate of cleavage and hatching were 25.0% and 15.0%, 32.5% and 20.0%, 37.5% and 20.0%, 52.5%, 27.5%, 47.5% and 25.0%, respectively. And developmental rates to the expended blastocyst stage of embryos frozen at zygote stage was significantly(p<0.05) lower rather than those in 2, 8-cell and morulae stage.

• Korean Journal of Cognitive Science
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• v.31 no.4
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• pp.103-136
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• 2020

This study compares the parafovea preview effect of adolescent group and adult group with different ages using eye tracking experiment. Also, this study confirms that the starting point parameter of the one boundary diffusion model can explain the data obtained through eye tracking experiments. In two experiments, parafoveal information processing was examined using the boundary technique. In Experiment 1, reading times were compared between the conditions given high frequency words preview versus masking preview. In Experiment 2, the condition in which low frequency words were given to parafovea preview information and the condition in which parafovea preview was masked were compared. We found that both the adolescent group and the adult group showed a parafovea preview effect. Also, first fixation, single fixation, and gaze duration of the two groups were different based on the word property shown in the parafovea. The first fixation data obtained in the two experiments were divided into quantiles and fitted into one boundary diffusion model. From the results, we argue that the parafovea preview information processing in the reading was described as the starting point parameter of the one boundary diffusion model.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2000.06a
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• pp.383-389
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• 2000

본고는 한영번역기 개발을 위한 기초 작업으로 '와/과'구문에 나타나는 여러 가지 패턴을 정리하고 이들 구문에서 보이는 중의성 문제를 해결하고자 하였다. 이러한 작업을 위해서는 자료 수집 및 분석이 우선이기 때문에 코퍼스에서 '와/과'구문을 뽑아서 분석하여 규칙을 마련하였다. 여기에서 사용된 자질연산문법(FCG)은 자연언어처리를 위한 문법으로 변형규칙과 수형도의 개념 없이 자질을 이용한 연산 체계로서 언어처리를 하고자 하는 문법이다. 이 이론을 바탕으로 규칙을 세우고 실제 언어 자료를 뽑아서 테스트를 하여 95%의 성공률을 보여주었다. 그러나 여기서의 연구는 '와/과'구문의 처리를 위한 가장 뼈대가 되는 기초연구이며, 앞으로 좀 더 많은 처리가 이루어져야 하리라 생각된다.

• (The) Research of the performance art and culture
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• no.32
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• pp.701-738
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• 2016

The Geomungo(거문고) is a instrument of Gogureoy(高句麗). The instrument had covered a lot of Korea, so it have become a important musical instrument in Korea. Hayasi Genjo(林謙三), Japanese scholar, had maintained his opinion that the Geomungo of Gogureoy is the Wagonghu(臥??), and the Geomungo was formed later, the record of Kimbusik, wrighter of the History of Three Kingdom(三國史記), was incredible. Lee-Hyegu refuted his hypothesis because the introduction on the Wagonghu of Japan have been inaccurate. Since then, many scholars of Korea have studed on the Geomungo of Gogureoy. But their study of the Geomungo was inclined to the topic, relation of the Geomungo and the Wagonghu, or the Wagonghu, the origin of the Geomungo. And They have thought that the record of Kimbusik's was truth. Kimbusik had recorded that Wangsanak(王山岳) had made the Geomungo from the Chilheoyn-Geum(七絃琴, Seven stringed Zither. 古琴). But the Geomungo was different from Geum(琴), but similar to Wagonghu. Many ancient tomb have been unearthed in the old land of Gogureoy, and the were many tomb painting of Gogureoy Geomungo. They were many different style, the form, the size, the number of strings and the position of the musician. So I think that many various type of the Geomungo had been exsited in Gogureoy they had become a prestyle of the Geomungo. The Geomungo was originated from the Wagonghu, its form was similar to the Geomungo. The many scholars considered that it is truth, the Wagonghu was handed down from China, and was spreded to Japan. But there were the Wagonghu in the early Joseon(古朝鮮), The song of the early Joseon, Gongmudohaga(公無渡河歌). The song was accompanied by the Wagonghu. We can read off, at the Song, the Wagonghu had exsisted in the early Joseon. So I think cautiously on that point, the Wagonghu of the Early Joseon was old than that of China, and thd Geomungo of Gogureoy was originated from the Wagonghu of the Early Joseon.

• Current Research on Agriculture and Life Sciences
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• v.9
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• pp.87-94
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• 1991

An approximate analytical method to predict performance characteristics of the stirling engines in a preliminary design stage was investigated. In basic equations proposed by walker, typical temperatures of working fluids in expansion and compression spaces were treated the same as those of working fluids in heater and cooler respectively. While the temperature of working fluids in the expansion space was actually lower than that of working fluids in the heater, the temperature of working fluids in the compression space was higher than that of working fluids in the cooler. The aim of this study divided typical temperatures of working fluids in expansion and compression spaces into serval grades, and than evaluated the experimental engine. As the result, the case which working fluids temperature of expansion space was treated as lower than the heater temperature and which that of compression space was treated as higher than the cooler temperature, was much closer to the experimental value.

• The Journal of the Korea Contents Association
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• v.10 no.2
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• pp.433-443
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• 2010

This study aimed understanding the effects of brand image about a wine bar on guest behaviors. A data was collected from individuals who visited wine bars in Seoul, Korea. This study intended (1) to identify the dimensions of brand image about a wine bar by factor analysis, (2) to analyze the dimensions of guest loyalty and revisit intention. This study also examined 1) the effects of brand image about a wine bar on guest satisfaction, loyalty, and revisit intention, 2) the effects of guest satisfaction on guest loyalty and revisit intention, and lastly, the effect of guest loyalty on revisit intention. The results of this study revealed that (1) positive effects were found between the brand image about a wine bar and some dimensions of guest satisfaction, (2) positive effects were observed between the brand image about a wine bar and some dimensions of revisit intention, (3) the brand image about a wine bar had partially positive effects on guest loyalty, (4) guest satisfaction had a positive relationship with revisit intention, (5) guest satisfaction had a positive relationship with loyalty, and (6) positive relationship existed between loyalty and revisit intention.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.5
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• pp.111-120
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• 2016

Wire recognition is one of the important tasks in chip reverse engineering since connectivity comes from wires. Recognized wires are used to recover logical or functional representation of the corresponding circuit. Though manual recognition provides accurate results, it becomes impossible, as the number of wires is more than hundreds of thousands. Wires on a chip usually have specific intensity or color characteristics since they are made of specific materials. This paper proposes two stage wire recognition scheme; image binarization and then the process of determining whether regions in binary image are wires or not. We employ existing techniques for two processes. Since the second process requires the characteristics of wires, the users needs to select the typical wire region in the given image. The histogram characteristic of the selected region is used in calculating histogram similarity between the typical wire region and the other regions. The first experiment is to select the most appropriate binarization scheme for the second process. The second experiment on the second process compares three proposed methods employing histogram similarity of grayscale or HSV color since there have not been proposed any wire recognition method comparable by experiment. The best method shows more than 98% of true positive rate for 25 test examples.