소타액선에 발생된 선양 낭포암

권경윤,이경호,김동윤,최갑식,Kwon Kyung-Yun,Lee Kyung-Ho,Kim Dong-Youn,Choi Karp-Shik 대한영상치의학회 1997 Imaging Science in Dentistry Vol.27 No.1

Adenoid cystic carcinoma is a malignant salivary gland tumor with typical histologic patterns. The majority of these tumors occurs in the minor salivary glands. especially mucosa of the hard palate. The authors experienced the patients, who complained the tumor-like soft tissue masses on the palatal and mouth floor area. After careful analysis of clinical, radiological and histopathological findings, we diagnosed them as adenoid cystic carcinomas in the minor salivary glands, and obtained results were as follows : 1. Main clinical symptoms were a slow growing soft tissue mass with normal intact mucosa on the palatal area, and soft tissue mass with mild pain on the mouth floor area. 2. In the radiographic exarnminations, soft tissue masses were observed with invasion to adjacent structures, and moderate defined, heterogeneous soft tissue mass with enhanced margin, respectively. 3. In the histopathologic exarnminations, dark-stained, small uniform basaloid cells in the hyaline or fibrous stroma were observed as solid and cribriform patterns, respectively.

PIN, Adjusted PIN, and PSOS: Difference of Opinion in the Korean Stock Market

권경윤,엄경식,강장구 한국증권학회 2017 Asia-Pacific Journal of Financial Studies Vol.46 No.3

Duarte and Young (2009) decompose the probability of information-based trading PIN into adjusted PIN (AdjPIN) and probability of trading caused by symmetric order flow shocks (PSOS). We explore sources of PSOS in the Korean stock market and examine the relation between PSOS and stock returns. Using transaction data with trader types and initiator information, we find that AdjPIN is not priced, while PSOS is negatively priced, a finding that Lai et al. (2014) label “puzzling.” We find that the negative price of PSOS comes from differences of opinion among domestic individual investors on the significance of public news.

악골에 발생된 섬유성 골병소의 임상 방사선학적 연구

권경윤 慶北大學校 齒科大學 1997 慶北齒大論文集 Vol.14 No.-

악골에 발생된 섬유성 골병소 중 섬유성 이형성증 71증례와 골화성섬유종 35증례,치근단백악질이형성증 30증례의 임상방사선학적소견을 비교하여 다음의 결론을 얻었다. ·섬유성 이형성증은 10대(30.0%)에서,골화성 섬유종은 20∼30(45.8%),치근단백악질이형성증은 30대(31.2%)에서 가장 호발되었으며,세 질환 모두 여성에서 더 호발되었다. ·섬유성 이형성증과 골화성섬유종의 주소는 무통성의 종창이 가장 많았고,치근단백악질이형성증은 방사선검사에서 우연히 발견된 경우가 가장 많았다. ·섬유성 이형성증은 상악 구치부(35.2%)에서,골화성섬유종은 하악 구치부(57.1%)에서 호발되었고,치근단백악질이형성증은 하악 전치부(73.3%)에 호발되었다. ·병소의 성숙도는 섬유성 이형성증에서 57.6%가 방사선불투과상으로 나타났고,골화성섬유종과 치근단백악질이형성증은 방사선투과상과 방사선불투과상의 혼합병소가 각각 74.2%,60.0%로 가장 많았다. ·주변 정상 골조직과의 경계는 섬유성 이형성증에서 주변 정상골조직과 분명한 경계를 구별할 수 없는 경우가 81.7%로 가장 많았고,골화성섬유종은 주변 정상골조직과 분명한 과골경계가 나타나는 경우가 60.0%였고,치근단백악질이형성증은 70.0%에서 분명한 경계가 나타났다. ·병소와 관련된 피질골의 비박과 팽융은 섬유성 이형성증에 비해 골화성섬유종(65.7%)에서 우세하게 나타났고,치근단백악질이형성증에서는 나타나지 않았다. ·병소와 관련된 인접 치아에 대한 영향은 섬유성 이형성증에서는 치조백선의 소실(74.2%)이 많이 나타났고,골화성섬유종에서는 치근흡수(25.0%)가 많았다. ·병소와 인접한 하악관의 전위와 상하악골의 수직고경의 증가는 섬유성 이형성증과 골화성섬유종에서 비슷하게 나타났다. ·섬유성 이형성증은 5.9%가 단골성으로 발생되었고,골화성섬유종은 모두 단독 병소였으며,치근단백악질이형성증은 43.7%가 다발성으로 나타났다.

Effects of Sodium Hypochlorite and Acidified Sodium Chlorite on the Morphological, Microbiological, and Sensory Qualities of Selected Vegetables

권경윤,강경아,윤기선 한국식품과학회 2011 Food Science and Biotechnology Vol.20 No.3

The effects of washing with sodium hypochlorite (NaClO) and acidified sodium chlorite (ASC) on the reduction of various pathogens contaminated produce, as well as the change in sensory qualities during storage and morphological characteristics of the surface of the washed produce, including cherry tomato, cucumber, and carrot were evaluated. Produce was inoculated with Bacillus cereus, B. cereus spore, Campylobacter jejuni, Salmonella Typhimurium, and Listeria monocytogenes and then washed with 100, 150, or 200 ppm NaClO and stored for 11 days at 4^oC. The produce contaminated with S. Typhimurium or L. monocytogenes was also washed with 100 ppm NaClO containing 5% acetic acid and 500 ppm ASC. The greatest washing efficacy was observed in B. cereus, followed by S. Typhimurium, L. monocytogenes,and C. jejuni. NaClO with 5% acetic acid was significantly (p<0.05) more effective than 500 ppm ASC at S. Typhimurium, but not at L. monocytogenes, regardless of the types of produce, while ASC was the most effective sanitizer for L. monocytogenes in cucumber. Scanning electron microscopy showed that washing with NaClO removed the pathogens, but also part of the wax layer from the surface, which might affect sensory qualities of the produce during storage.

악골 섬유성 골병소의 방사선학적 연구

권경윤,최갑식 大韓口腔顎顔面 放射線學會 1998 Imaging Science in Dentistry Vol.28 No.1

The purpose of this study was to obtain information on the clinical and radiographic features of the fibro-osseous lesions in the jaws. For this study. the author examined and analysed the clinical records and radiographs of 71 cases of 68 patents in fibrous dysplasia, 35 cases of ossifying fibroma and 30 cases of 16 patients of periapical cemental dysplasia diagnosed by clinical and radiographic or histopathological examinations. The obtained results were as followings: 1. Fibrous dysplasia occurred most frequently in the 2nd decade(30.0%), ossifying fibroma in the 3rd-4th decades, periapical cemental dysplasia in the 4th decade, and all of three lesions showed slight predilection in females. In most cases, chief complaints were painless facial swelling in fibrous dysplasia and ossifying fibroma, and periapical cemental dysplasia was found accidentally in radiographs. 2. Fibrous dysplasia was occurred more frequently in maxilla, ossifying fibroma in mandible and both lesions in premolar-molar area. Periapical cemental dysplasia was occurred most frequently in the mandibular anterior area. The size of fibrous dysplasia was larger than that of ossifying fibroma, and the shape of ossifying fibroma was more round and elliptical than fibrous dysplasia whose was fusiform. 3. Fibrous dysplasia was shown homogeneous radiopaque shadow of 57.6% and ossifying fibroma & periapical cemental dysplasia were shown mixed appearance of radiolucency and radiopacity shadows at 74.2%, 60.0%, respectively. 4. Fibrous dysplasia was entirely shown poorly defined at 87.7%, but ossifying fibroma & periapical cemental dysplasia were shown well outlined at 60.0%, 70.0%, respectively. 5. Cortical thinning and expansion were observed in fibrous dysplasia and ossifying fibroma, and severe in ossifying fibroma than fibrous dysplasia, and those signs were not seen in periapical cemental dysplasia. Loss of lamina dura was dominant in fibrous dysplasia and root resorption was dominant in ossifying fibroma. Displacement of mandibular canal and the degree of the increase of vertical dimension were maxillary sinus were dominant in fibrous dysplasia. 6. Polyostotic fibrous dysplasia was occurred at 5.9%, Multiple periapical cemental dysplasia at 43.7%, Occurrence rate in the edentulous area of fibrous dysplasia and ossifying fibroma were 7.0%, 8.6%, respectively.

비자발적 애널리스트 보고서가 지닌 정보로서의 가치

권경윤(Kyung Yoon Kwon),양유진(Yujin Yang),엄경식(Kyong Shik Eom) 한국증권학회 2015 한국증권학회지 Vol.44 No.3

본 논문은 코스닥시장이 시장 정보량이 매우 적은 자체 상장기업에게 정기적으로 애널리스트보고서를 발간하도록 도와주기 위해 도입했던 “KRP 제도(2007∼2011)”가 참여기업의 주가 정보성(price informativeness)을 제고하는데 효과적이었는지를 분석하였다. 주가 정보성을 반영하는 시장미시구조 변수로는 주가 노이즈, 정보비대칭 및 가격효율성을 활용하였다. 2008년부터 2011년까지KRP 참여기업 및 매칭기업 주식의 일중 및 일별 자료를 사용하여 탐색적 차이분석과 이중차분(DID) 기법 분석을 수행한 결과, 첫째 KRP 참여기업의 주가 노이즈는 보고서 발간 이후 유의미하게 감소하였다. 이는 보고서 발간 이후 매칭기업의 주가 노이즈 감소를 차감하고도 유의미하게감소한 값으로, KRP 참여 이후 해당 기업의 주가 노이즈는 감소, 즉 정보성은 개선되었음을 의미한다. 둘째, 보고서 발간 이후 참여기업의 정보비대칭은 통계적으로 한계적이기는 하지만 감소하였고, 가격효율성은 일정 부분 유의미하게 개선되었다. 이상의 결과는 KRP 보고서라는 제약적이고도 비자발적 형태의 보고서조차 정보성이 있을 만큼 일부 코스닥 상장기업에 정보불균형의정도가 심각함을 반증한다. 또한 시장 차원에서 제공하는 비자발적 보고서도 시장의 정보비대칭을일정 수준 개선할 수 있으며, 제도상의 약한 고리를 보완하여 이를 적절히 재구현한다면 향후코스닥 시장의 질적 수준을 향상시키는 데 도움이 될 수 있음을 시사한다. In 2007, KOSDAQ introduced the ‘KRX Research Project (KRP)’ to subsidize analyst reports on firms with low informational transparency; it abruptly terminated the project in 2011. In this paper, we examine whether the KRP improved the price informativeness for the covered firms by analyzing changes in three variables: stock price noise, asymmetric information, and price efficiency. Using intraday and daily data, we perform an exploratory difference test and a difference-in-difference (DID) test utilizing KRP-covered firms and their matched firms from 2008 to 2011. Our results show that the price noise of the sample firms was statistically significantly reduced following the implementation of the project. It provides evidence that KRP contributed to improving the price informativeness for those firms with low informational transparency. We also find that KRP reports somewhat improved information asymmetry and price efficiency. However, this result shows mixed statistical significance. Overall, our results suggest that informational asymmetries have been severe for some KOSDAQ firms, since analyst reports containing fairly limited information nonetheless managed to have a significant impact. Furthermore, our results indicate that the decision to terminate the KRP was a mistake, and it would be desirable to reinstate KRP, with certain modifications to address concerns that arose in the original implementation.

개인투자자의 투자심리와 주식수익률

강장구,권경윤,심명화 한국재무학회 2013 한국재무학회 학술대회 Vol.2013 No.05

본 연구는 개인투자자의 집단적 거래행태에 반영된 이들의 투자심리와 주식수익률의 관계를 분석한다. 투자심리가 자산 가격에 영향을 주기 위해서는 두 가지 전제가 필요하다. 하나는 개인투자자들이 집단적 거래이고, 다른 하나는 차익거래의 제한이다. 우리는 국내 주식시장에서 일부 주식에 대해 이 두 가지 조건이 충족되어 투자심리와 수익률의 유의한 관계가 관찰됨을 보고한다. 본 연구의 주요 발견은 다음과 같다. 첫째, 국내 주식시장에도 개인투자자들의 집단적 거래행태가 존재함을 확인한다. 주식 간 개인투자자 매도-매수 거래량불균형의 상관관계가 유의하게 양수로 나타난 것이다. 이는 개인투자자들은 시기에 따라 매도 혹은 매수 일방으로 거래하는 경향이 있음을 시사한다. 둘째, 개인투자자들의 집단적 거래행태에 반영된 그들의 투자심리가 주식 가격에 영향을 미침을 발견한다. 특히 개인투자자들이 주로 거래하는 주식, 차익거래가 어려운 주식일수록 주식 가격에 대한 개인투자심리의 영향이 유의하다. 마지막으로, 주문 유형에 따라 개인투자자 거래의 상관 정도가 다름을 확인한다. 시장가주문 매수량과 매도량의 차이로 측정한 매도-매수 거래량불균형에 비해, 지정가주문 매수량과 매도량의 차이로 측정한 거래량불균형 간의 상관계수는 매우 낮다. 이는 개인투자자들이 시장가주문을 이용할 때 더 몰려 거래하는 경향이 있다고 해석 가능하다. We investigate the relationship between retail investor sentiment and stock returns in the Korean stock market using intraday transaction and order flow data. The assertion that changes in investor sentiment have a significant effect on asset returns rests on two assumptions. First, the aggregate trading of retail investor is systematic. Second, arbitrage is limited. We find the trades of retail investors are significantly correlated, and moreover, that this systematic retail trading can help explain monthly stock return variation even after controlling commonly used asset pricing factors. Furthermore, we find that the incremental power of retail trading behavior in explaining return comovements is larger and more significant for stocks that are actively traded by retail investors and that are difficult to arbitrage. These findings suggest that retail investor sentiment which is reflected in their trading activities plays a role in price formation. In addition, we distinguish between market orders and executed limit orders, and find that market order trades of retail investors are more highly correlated than limit order trades. This is consistent with the argument that market orders are aggressive trades and, therefore, a better measure of investor sentiment.

예비교사들의 개인 교육용 자료 제작 및 사용과정에서의 외부 자료 활용에 대한 교육용 저작권 인식 실태 조사

임혜원,권경윤,김민수,주민호 한국인터넷윤리학회 2019 The Digital Ethics(디지털 윤리) Vol.3 No.2

As technology advances, various educational media have been developed. And teachers are frequently infringing copyrights in the process of creating and utilizing educational materials. In this study, we measured the status of copyright recognition among 73 prospective teachers by dividing it into general and educational copyrights. The analysis shows that there is a lack of awareness of educational copyrights than general copyrights, especially in terms of utilizing educational copyright knowledge. This suggests that prospective teachers need to be provided copyright education.

소타액선에 발생된 선양 낭포암

이경호,최갑식,권경윤,김동윤 大韓口腔顎顔面 放射線學會 1997 Imaging Science in Dentistry Vol.27 No.1

Adenoid cystic carcinoma is a malignant salivary gland tumor with typical histologic patterns. The majority of these tumors occurs in the minor salivary glands, especially mucosa of the hard palate. The authors experienced the patients, who complained the tumor-like soft tissue masses on the palatal and mouth floor area. After careful analysis of clinical, radiological and histopathological findings, we diagnosed them as adenoid cystic carcinomas in the minor salivary glands, and obtained results were as follows: 1. Main clinical symptoms were a slow growing soft tissue mass with normal intact mucosa on the palatal area, and soft tissue mass with mild pain on the mouth floor area. 2. In the radiographic examminations, soft tissue masses were observed with invasion to adjacent structures, and moderate defined, heterogeneous soft tissue mass with enhanced margin, respectively. 3. In the histopathologic examminations, dark-stained, small uniform basaloid cells in the hyaline or fibrous stroma were observed as solid and cribriform patterns, respectively.

개인투자자의 투자심리와 주식수익률

강장구 ( Jang Koo Kang ),권경윤 ( Kyung Yoon Kwon ),심명화 ( Myoung Hwa Sim ) 한국재무관리학회 2013 財務管理硏究 Vol.30 No.3

본 연구는 개인투자자의 집단적 거래행태에 반영된 투자심리와 주식수익률의 관계를 분석한다. 투자심리가 자산 가격에 영향을 주기 위해서는 두 가지 전제가 필요하다. 하나는 개인투자자들이 집단적 거래이고, 다른 하나는 차익거래의 제한이다. 우리는 국내 주식시장에서 일부 주식에 대해 이 두 가지 조건이 충족되어 투자심리와 수익률의 유의한 관계가 관찰됨을 보고한다. 본 연구의 주요 발견은 다음과 같다. 첫째, 국내 주식시장에도 개인투자자들의 집단적 거래행태가 존재함을 확인한다. 주식 간 개인투자자 매수-매도 거래량불균형의 상관관계가 유의하게 양수로 나타난다. 이는 개인투자자들은 시기에 따라 매수 혹은 매도 일방으로 거래하는 경향이 있음을 시사한다. 둘째, 개인투자자들의 집단적 거래행태에 반영된 그들의 투자심리가 주식 가격에 영향을 미침을 발견한다. 특히 개인투자자들이 주로 거래하는 주식, 차익거래가 어려운 주식일수록 주식 가격에 대한 개인투자심리의 영향이 유의하다. 마지막으로, 주문 유형에 따라 개인투자자 거래의 상관 정도가 다름을 확인한다. 시장가주문 매수량과 매도량의 차이로 측정한 매수-매도 거래량불균형에 비해, 지정가주문 매수량과 매도량의 차이로 측정한 거래량불균형 간의 상관계수는 매우 낮다. 이는 개인투자자들이 시장가주문을 이용할 때 더 몰려 거래하는 경향이 있다고 해석 가능하다. We investigate the relationship between retail investor sentiment and stock returns in the Korean stock market using intraday transaction and order flow data. The assertion that changes in investor sentiment have a significant effect on asset returns rests on two assumptions. First, the aggregate trading of retail investor is systematic. Second, arbitrage is limited. We find the trades of retail investors are significantly correlated, and moreover, that this systematic retail trading can help explain monthly stock return variation even after controlling commonly used asset pricing factors. Furthermore, we find that the incremental power of retail trading behavior in explaining return comovements is larger and more significant for stocks that are actively traded by retail investors and that are difficult to arbitrage. These findings suggest that retail investor sentiment which is reflected in their trading activities plays a role in price formation. In addition, we distinguish between market orders and executed limit orders, and find that market order trades of retail investors are more highly correlated than limit order trades. This is consistent with the argument that market orders are aggressive trades and, therefore, a better measure of investor sentiment.