Facial Exposure Dose Assessment During Intraoral Radiography by Radiological Technologists

유환,양한준 대한방사선과학회 2014 방사선기술과학 Vol.37 No.3

The study examined the changes in the decreased facial exposure dose for radiological technologists depending on increased distance between the workers and the X-ray tube head during intraoral radiography. First, the facial phantom similar to the human tissues was manufactured. The shooting examination was configured to the maxillary molars for adults (60kVp, 10mA, 50msec) and for children (60kVp, 10mA, 20msec), and the chamber was fixed where the facial part of the radiation worker would be placed using the intraoral radiography equipment. The distances between the X-ray tube head and the phantom were set to 10cm, 15cm, 20cm, 25cm, 30cm, 35cm, and 40cm. The phantom was radiated 20 times with each examination condition and the average scattered doses were examined. The rate at the distance of 40cm decreased by about 92.6% to 7.43% based on the scattered rays radiated at the distance of 10cm under the adult conditions. The rate at the distance of 40cm decreased by about 97.6% to 2.58% based on the scattered rays radiated at the distance of 10cm under the children conditions. Protection from the radiation exposure was required during the dental radiographic examination.

한중FTA가 중국 시장에 미치는 영향에 관한 연구 -한국 화장품을 수출 중심으로-

유환,장휘 대한경영학회 2019 대한경영학회 학술발표대회 발표논문집 Vol.2019 No.1

중국 장시성 누오(儺) 가면의 특성을 활용한 3D 디지털 패션디자인

유환,이연희 복식문화학회 2022 복식문화연구 Vol.30 No.3

The aim of this study was to develop Jiangxi Nuo masks using 3D digital fashion design technology and suggest various ways to utilize traditional culture based on the characteristics of Nuo masks, a traditional Chinese artifact of intangible cultural significance. The researchers conducted a literature review to gather information about Nuo culture and masks that could represent Jiangxi. Features of the masks were analyzed and classified. The result are as follows. First, the symbolic characteristics of Jiangxi’s Nuo masks can be divided into those based on their origin and history, the user’s social status, and the notions of primitive beliefs of the chosen people, such as naturism and totemism. Second, Nuo masks’ splendid decorations convey meanings such as luck, the bixie, longevity, wealth, and peace in the family. Third, playfulness in mask-making is about dismantling the original form of the mask, re-creating it through application. Fourth, the masks express primitiveness mostly by conserving the wood’s original color or material. The initial masks carved to represent images of figures aptly deliver the primitive forms and images of Nuo culture. In this study, Nuo masks were developed and produced using the 3D digital technology CLO 3D by adopting the expressive characteristics and applying design methods such as asymmetricity, exaggeration, and modification. The results of this study demonstrate the possibility of creating diverse as well as economical designs through the reduction of production.

기반 기술 : 주석 도금한 커넥터의 접촉 하중의 변화에 의한 전기 접촉저항 변화에 관한 연구

유환신 ( Hwan Shin Yu ),오만진 ( Man Jin Oh ),박형배 ( Hyung Bae Park ),유환신 ( Hwan Shin Yu ),오만진 ( Man Jin Oh ),박형배 ( Hyung Bae Park ) 한국항행학회 2014 한국항행학회논문지 Vol.18 No.4

In order to investigate the effect of contact load, which is one of the fretting corrosion factors affecting the electric connector, a coupled fretting corrosion specimens were prepared using a tin-plated brass coupon with a thickness of 3 μm. Electric resistance of the contact was measured during the fretting corrosion test period. There was increase in resistance with fretting cycles. The change in resistance can be classified by 3 stages. The first stage exhibited low and stable resistance. Second stage showed steady increment of the resistance and third stage showed very high and intermittent resistance. The relationship between the failure cycle (Nf) and contact force (P) can be drawn as; It is possible to draw the prediction equation for the failure cycle of the electric connector corresponding to the very high and intermittent resistance under various environment conditions through the fretting tests under various conditions such as load, displacement, temperature.

은행 금융상품에서 프라이빗 뱅커의 전문투자형 사모펀드 추천 의사결정

유환,이영재 한국정보시스템학회 2019 정보시스템연구 Vol.28 No.4

Purpose The study aims to develop a data-based decision model for private bankers when recommending hedge funds to their customers in financial institutions. Design/methodology/approach The independent variables are set in two groups. The independent variables of the first group are aggressive investors, active investors, and risk-neutral type investors. In the second group, variables considered by private bankers include customer propensity to invest, reliability, product subscription experience, professionalism, intimacy, and product understanding. A decision-making variable for a private banker is in recommending a first-rate general private fund composed of foreign and domestic FinTech products. These contain dependent variables that include target return rate(%), fund period (months), safeguard existence, underlying asset, and hedge fund name. Findings Based on the research results, there is a 94.4% accuracy in decision-making when the independent variables (customer rating, reliability, intimacy, product subscription experience, professionalism and product understanding) are used according to the following order of relevant dependent variables: step 1 on safeguard existence, step 2 on target return rate, step 3 on fund period, and step 4 on hedge fund name. Next, a 93.7% accuracy is expected when decision-making uses the following order of dependent variables: step 1 on safeguard existence, step 2 on target return rate, step 3 on underlying asset, and step 4 on fund period. In conclusion, a private banker conducts a decision making stage when recommending hedge funds to their customers. When examining a private banker's recommendations of hedge funds to a customer, independent variables influencing dependent variables are intimacy, product comprehension, and product subscription experience according to a categorical regression model and artificial neural network analysis model.

의미 구조와 인지적 범주화의 측면에서 본 동의중복어의 개념과 범위

유환일 ( Liu Huanyi ) 연세대학교 언어정보연구원 2021 언어사실과 관점 Vol.52 No.-

This paper studied the semantic structure and cognitive categorization patterns in two views of semantic transparency for overlapping of synonymous word that qualify as a listme. The results showed that the semantic structure is ‘meaning selection α₁ (selecting the meaning of any component)’ and ‘meaning selection α₂ (selecting the meaning of a particular component)’. Through cognitive categorization patterns, the formation of overlapping of synonymous word was found to have resulted from increased semantic transparency, i.e. reduced entropy of information delivery. In particular, in the case of overlapping of synonymous word with meaning selection α₂, the surplus ‘transparent unit’ is notable for its function of increasing negentropy.

사이드 뷰 2D 게임에서의 고수준 길찾기 알고리즘에 대한 연구

유환진(Hwan-Jin You),이범로(Bum-Ro Lee) 한국컴퓨터정보학회 2023 한국컴퓨터정보학회 학술발표논문집 Vol.31 No.2

Structure-property Relationships for Partially Aliphatic Polymides

유환철,Vijay Kumar S,최지영,Kazuaki Kudo,정찬운 한국고분자학회 2010 한국고분자학회 학술대회 연구논문 초록집 Vol.2010 No.10

Effect of stereochemistry of aliphatic diamine on properties of fully or partially aliphatic polyimides

유환철,정재우,정찬문 한국고분자학회 2014 한국고분자학회 학술대회 연구논문 초록집 Vol.2014 No.4

스포츠 개념 재정립의 필요성과 방향

유환일 ( Yoo Hwanil ),박성주 ( Park Sungjoo ) 한국체육학회 2020 한국체육학회지 Vol.59 No.6

Assuming the genetic tie of sport to playfuness, competitiveness, and physicality, this paper has two goals as follows: it points out the limitations of existing concepts on these elements of sport; it then emphasizes the necessity of expanding on the concept of sport in light of social change. In order to achieve the goals, this paper reviews the literature by sport philosophers and examines the existent concepts of sport. Next, the main points are examined by analyzing the controversies over the concepts of sport, caused by the emergence of new sports. In the final section, we show the limitations of prior concept of sport, and suggest the necessity, as well as the direction, of conceptual modification of sport. Because the definition and value of sport has been changed over time, this study argues to redefine the concept of sport. In this way, fallacies can be minimized when we define sport within sociocultural context rather than using the existing theory which defines sport based on its inner components only.