• 한국재료학회지
• /
• 제17권1호
• /
• pp.25-30
• /
• 2007

The in-situ scanning electron microscopy observation of real-time hillock evolution in pure hi thin films on glass substrate during Isothermal annealing was analyzed quantitatively to understand the compressive stress relaxation mechanism by focusing on the effect of Mo interlayer between Al film and glass substrate. There is a good correlation between the hillock-induced stress relaxation by in-situ scanning electron microscopy observation ana the measured stress relaxation by wafer curvature method. It is also clearly shown that the existence of Mo interlayer plays an important role in hillock formation probably due to the large difference in interfacial diffusivity of Al films.

• 한국식생활문화학회지
• /
• 제20권4호
• /
• pp.405-415
• /
• 2005

This study was to investigate firstly a way of promoting health through increasing kimchi ingestion by means of analyzing the points to be improved on the state of taking kimchi, the traditional Korean food, the degree of kimchi likings and the problems of the kimchi on the market, and secondly the other way of having our favorite age-old kimchi quality improved as well as making kimchi inherited by means of collecting useful related materials via questionnaire survey intended for 316 housewives of $20{\sim}50$ years old who lived in Seoul. In the degree of preferences, 92% of them liked kimchi, being considered that higher the age, higher the nostalgia with perception of traditional food. On the problems to be improved of the kimchi on the market, the most answers, 48.73%, said that the hygiene was worrying, indicating that the most overriding problem to be improved in the kimchi on the market was all-out sanitary management. On the thinking of kimchi, the feeling of that the kimchi was the most Korean-like was predominant.

• 대한치위생과학회지
• /
• 제3권1호
• /
• pp.45-50
• /
• 2020

A total of nine oral health educators for 17 persons with developmental disabilities conducted oral health education once a week for four weeks. The oral health educators provided oral health knowledge education and individual toothbrushing teachings. The developmentally disabled people in their 20s and 30s conducted oral health education without a guardian. Ten people who completed all the four pieces of training had no significant improvement in the toothbrushing method and the recommended number of toothbrushing sessions a day, as well as a lack of growth in oral health knowledge. However, 58.8% of the individuals expressed satisfaction with the oral health education program, whereas, 52.9% expressed the desire for a re-education. Although the ratio of teachers to students was 1:2, and the oral health education conducted four times, it was insufficient to promote a successful oral health behavior or knowledge for people with developmental disabilities. Therefore, as a suggestion, oral health education for people with developmental disabilities ought to proceed with their guardians to promote the success of the training.

• 대한치과의료관리학회지
• /
• 제7권1호
• /
• pp.10-20
• /
• 2019

Korean dental hygienists perform more tasks in dental clinics than are described in the law. The purpose of this study was to investigate the actual work of Korean dental hygienists in dental clinics using an observational study design. Two dental hygienists observed and recorded the work performed in 1 day from the time of commencement to the time of leaving work by 18 dental hygienists working in the dental clinic in a single area. Data management, prevention of infection, counseling, calculus removal, radiography, assistance of fixed orthodontic treatment, assistance of fixed prosthetic treatment, and preparation for implant surgery were recorded. Among the tasks that take more than 1 min, the most time-consuming tasks were document management, infection control, consultation, calculus removal, preparation for implant surgery, assistance of orthodontic treatment, and assistance of fixed prosthetic treatment. Korean dental hygienists are performing various tasks, such as infection control, dental hospital/clinic management, oral disease prevention, and dental treatment assistants.

• 대한치과의료관리학회지
• /
• 제11권1호
• /
• pp.47-53
• /
• 2023

This study aims to analyze the research trends of the Journal of Korean Academy of Dental Administration and identify the characteristics of the journal. The research was based on 10 academic journals from 2013 to 2022 and related documents. The type of paper, research method, statistical analysis, topic classification, and research subject of 65 papers were extracted and categorized. As a result, the distribution of paper types was as follows: research articles accounted for 83.2%, review articles for 12.3%. In terms of research methods, questionnaire surveys were used in 46.2% of the papers, literature reviews in 23.1%, and national data analysis in 7.7%. Research topics included dental manpower at 20.0%, infection control at 7.7%, dental information at 6.2%, patient safety at 6.2%, and oral health care quality at 6.2%. 72.3% of the papers were quantitative studies, and the majority of research subjects were dental hygienists or dental hygiene students, accounting for 26.2% of the total. The Journal of Korean Academy of Dental Administration covers topics such as dental healthcare marketing, dental healthcare organization and management, dental healthcare information, dental healthcare policy, dental healthcare insurance, dental healthcare quality management, patient safety, medical disputes, and infection control. The authors are also contributed by a variety of dental personnel, including dentists, dental hygienists, and dental technicians.

• 대한기계학회논문집
• /
• 제12권4호
• /
• pp.790-805
• /
• 1988

본 연구에서는 유리섬유 강화 에폭시 복합재료의 파괴 강도와 피로 수명을 정 규분포, 로그 정규 분포와 2모수 및 3모수 Weibull 분포 함수의 기대값으로 살펴 보았 다. 2연속 응력 피로 실험 [작은 응력에서 큰 응력으로의 실험(low-high test), 큰 응력에서 작은 응력으로의 실험(high-low test)]의 결과도 분포 함수들을 사용하여 분 석하였다. 비통계학적 누적 손상 법칙들(non-statistical cumulative damage rules) 을 2연속 응력 피로 수명 분산 예측에 이용하기 위해서 동등 순위 가정(equal rank assumption)을 확장하여 수정하였다. 수정한 누적 손상 모형은 Miner의 법칙, Brou- tman과 Sahu의 손상모형 및 Hashin과 Rotem의 모형 등이다.

• 한국기계가공학회지
• /
• 제10권2호
• /
• pp.1-8
• /
• 2011

5-axis NC machining has a good advantage of the accessibility of tool motion by adding two rotary axes. It offers numerous advantages such as expanding machining fields in parts of turbo machineries like impeller, propeller, turbine blade and rotor, reasonable tool employment and great reduction of the set-up process. However, as adding two rotary axes, it is difficult to choose suitable machining conditions in terms of cutter path and cutter posture at a cutter contact point. Therefore in this paper, it is proposed to decide suitable machining condition through an experimental method such as adopting various cutter paths, cutter postures types. Also, in order to increase the efficiency of 5-axis machining, it is necessary to minimize the cutter posture changes and create a continuous cutter path while avoiding interference. This study, by using an MC-space algorithm for interference avoidance and an MB-spline algorithm for continuous control, is intended to create a 5-axis machining cutter path with excellent surface quality and economic feasibility. finally, this study will verify the effectiveness of the suggested method through verification processing.

• 한국전자파학회논문지
• /
• 제28권11호
• /
• pp.894-901
• /
• 2017

요동이 존재하는 환경에서 항법 장비 정확도의 한계 및 시스템 지연 오차 등으로 방위 위상 오차가 필연적으로 발생하는 항공기 탑재 SAR(Synthetic Aperture Radar)의 경우, 방위 위상 오차를 신호처리 알고리즘으로 추정하고 보상하는 자동 초점(Autofocus: AF) 기법 적용이 필수적이다. 본 논문에서는 수정된 가중치 최소 자승기법(Modified Weighted Least-Squares: MWLS)에 의한 자동 초점 알고리즘을 제안한다. 새로운 방식의 표적 선정 및 정렬과 방위 방향 반복 위상 추정 방식을 통해 기존 WLS보다 견고한 성능을 보이게 된다. 비행 시험을 통해 획득한 SAR 원시데이터에 제안한 방식을 적용하고 성능을 분석하여 제안한 방식의 유효함과 우수성을 입증하도록 한다.

• 디자인학연구
• /
• 제20권3호
• /
• pp.247-256
• /
• 2007

본 연구는 인간이 일상생활을 영위하는데 중요한 역할을 하는 눈이 노화되어 감으로서 노인의 시각 노화과정에서 보이는 시지각과 관련된 정보습득 및 해석상의 색지각을 통한 특징을 반영하여 노인의 주 생활환경인 유료 노인주거 시설의 실내 공용공간의 설계지침을 제시하는 것을 목적으로 한다. 일반시각과 70세와 80세 후반까지를 모의 수정체를 이용하여 각 세대별 시지각을 통한 색채의 오류판단을 파악하였다. 노화에 따른 노인의 황변화 및 색지각 특성을 바탕으로 실내 공용공간의 색채 설계 계획을 위한 기초자료로 사용하고자 한다. 본 연구의 결과로 인지 배색으로 유사조화 보다 대비조화를, 한색보다 난색계열을 사용함를 파악하였으며, 노인의 황변화에 따른 색지각 특성의 기초자료로서 활용될 수 있다.

• 환경생물
• /
• 제30권2호
• /
• pp.128-135
• /
• 2012

본 연구는 말똥성게(Hemicentrotus pulcherrimus)의 생식세포 및 pluteus 유생을 이용하여 중금속인 납(lead, Pb)과 아연(zinc, Zn)의 독성을 조사였다. H. pulcherrimus 배우자 및 배아에 미치는 Pb과 Zn의 독성은 각각 31, 63, 125, 250, 500 ppb 및 16, 31, 63, 125, 250 ppb의 농도에서 조사하였다. 0.5 M KCl 용액을 이용하여 방란 및 방정을 유도하였고, 수정률 및 정상 배아발생률의 조사는 수정 후 각각 10분 및 64시간째 관찰하여 시행하였다. Pb 노출 시 수정률은 대조군과 비교하여 유의적인 변화가 없었다. 그러나 정상 배아발생률은 농도가 높을수록 농도의존적으로 유의적인 감소를 보였다. Zn을 노출시켰을 경우 수정률과 정상 배아발생률은 농도가 높을수록 농도의존적인 유의적 감소를 나타냈다. H. pulcherrimus의 정상 배아 발생에 대한 독성치는 각각 Pb (반수 영향농도 ($EC_{50}$) 45.13 ppb, 95% Cl 40.12~50.05 ppb), Zn (반수영향농도 ($EC_{50}$) 19.82 ppb, 95% Cl 18.26~21.31 ppb)로 나타났다. 또한 Pb과 Zn의 무영향농도(NOEC)는 각각 <31.25 ppb 및 <15.63 ppb로 나타났고, 최소영향농도(LOEC)는 31.25 및 15.63 ppb로 나타났다. 본 연구 결과, H. pulcherrimus의 초기 배아발생 과정은 Pb과 Zn 등의 중금속에 높은 민감성을 보인다. 따라서 H. pulcherrimus는 해양생태계 위해 평가를 위한 시험생물로서 사용이 가능하다고 사료된다.