CBT를 이용한 안전한 멀티캐스트 그룹 관리

윤성현,장주만,조원환 高麗大學校附設 컴퓨터科學技術硏究所 1999 JOURNAL OF COMPUTER SCIENCE & ENGINEERING TECHNOLO Vol.2 No.-

보다 높은 대역폭에서 안전한 멀티캐스트 통신을 하고자 욕구는 기업, 정부, 그리고 인터넷을 사용하는 모든 단체에서의 고조되고 있고 또한 주요 관심사이다. 멀티캐스트 환경에서 보안성을 제공하기 위해 최근까지 진행되어 오고 있는 연구는 주로 그룹 키 관리 기법에 관한 것들이다. 본 논문에서는 화장성이 우수한 CBT 멀티캐스트 라우팅 프로토콜을 기반으로 안전한 인터넷 멀티캐스트를 위한 CBT기반 그룹 관리 시스템을 제안한다. 본 논문에서 제안하는 기법은 핵심라우터가 키 생성, 키 재구성, 그룹 가입, 탈퇴 등 그룹 관리 뿐 아니라 여러 가지 보안사항을 고려한 기능도 제공해 준다. The need for high bandwidth, very dynamic secure internet multicast communications is increasingly evident in a wide variety of commercial, government, and Internet communities. One of the most recently researches is mainly about the group key management schemes. In this paper, We'll propose a CBT-based group management system with scalable CBT multicast routing protocol. The benefits of this proposed technique are that it offers not only key generation, rekey, group join and leaving but also many functions lated security of multicast group.

호주 초등 교육과정 운영 실태

조윤주 忠北大學校 敎育.生活硏究所 2002 한국교육논총 Vol.23 No.2

흰쥐의 신경병증성 통증에 대한경피신경전기자극과 미세전류신경근자극

이윤주,이충휘,조상현,임중우,남택상 大韓再活醫學會 1999 Annals of Rehabilitation Medicine Vol.23 No.3

사업장 소음 폭로에 의한 일과성 역치 상승과 회복

조수헌,하미나,한상환,주영수,성주헌,강종원,윤덕로,송동빈,이명학,김선태 大韓産業醫學會 1996 대한직업환경의학회지 Vol.8 No.2

To determine the recovery time from noise-induced temporary threshold shift(TTS), a prospective field study was conducted at three worksites where workers are known to be exposed high level of noise. Subjects were selected according to answers on a questionnaire which inquired about otological history and previous noise exposure, including avocational, military and occupational exposures. After excluding employee with past otologic problems, recent exposure to high level noise, and under medications, total 92 employees participated in the study. Among 92 participants, complete consecutive audiometric examinations were carried out at 0∼2 hours, 5∼7 hours, 14∼16 hours after worktime noise exposure on 26 participants wearing hearing protectors and 22 participants wearing no protective devices. The difference between the hearing level 0∼2 hours after noise exposure and 5∼7 hours is statistically significant by paired t-test(p<0.01). The median recovery times calculated from the data of 22 participants wearing no protective hearing devices are 15.6 hours at 4000Hz, and 7.7 hours, 10.3 hours, 8.4 hours at 1000Hz, 2000Hz and 8000Hz respectively. These data suggest that when measuring the pure tone audiometry for noise exposed workers, at least 16 hours noise-free interval is required.

수종의 dentin bonding agent가 도재라미네이트용 레진시멘트의 전단 결합강도 및 변연 누출에 미치는 영향

박윤기,조혜원,권주홍 大韓齒科器材學會 1993 대한치과재료학회지 Vol.20 No.1

The purpose of this study was to evaluate the influence of three dentin bonding agents on the shear bond strength, microleakage, and film thickness of resin cement for porcelain laminate veneer. Dentin & enamel surfaces were treated with three dentin bonding agents such as Scotchbond 2. All Bone 2, and Prisma Universal Bold 2 and were cemented by G-Cera cement for porcelain laminate veneer. For bond strength test, the specimens were stored in 37℃, 100% humidity for 48 hours and shear bond strength was measured with Instron testing machine (model no. 4201) at crosshead speed of 1.0mm/min. For microleakage and film thickness measurement, the specimens were stored in 37℃, 100% humidity for 7 days, thermocycled for 1000 cycles. Microleakage and film thickness of resin cement were measured with inverted metallurgical microscope(PME 311, Olympus, Japan). The results were as follows : 1. The shear bond strength of resin cement for porcelain laminate veneer to dentin was enhanced by the use of dentin bonding agent and All Bond 2 were effective in improving the shear bond strength to both enamel and dentin. 2. All Bond 2 were effective in reducing microleakage of veneers bonded to dentin, approximately to the same degree to the veneers bonded to enamel. But Prisma Universal Bond 2 and Scotchbond 2 failed to limit microleakage at the gingival margin of veneers bonded to dentin. 3. the 40% phosphoric acid in G-Cera system and the 10% phosphoric acid in All Bond 2 appeard equally effective in reducing microleakage of veneers bonded to enamel. 4. There were no significant increase in cement film thickness when using Prisma Universal Bold 2 or Scotchbond 2, but with All Bond 2 slight increase in the cement film thickness were present.

한국판 아동용 예일-브라운 강박 척도:신뢰도와 타당도 연구

정선주,이정섭,강윤형,조성진,서동혁,홍강의 대한소아청소년정신의학회 2000 소아청소년정신의학 Vol.11 No.1

목적 : 본 연구는 소아, 청소년의 강박 증상을 평가하기 위한 도구인 아동용 예일-브라운 강박척도(Childen's Yale-Brown Obsessive Compulsive Scale : Y-BOCS)의 한국판을 제작하여 그 신뢰도와 타당도를 검증하고자 시행되었다. 방법 : 강박장애로 진단된 42명의 아동과 청소년들을 대상으로 CY-BOCS를 시행하였다. 평가자간 신뢰도를 측정하기 위하여 20명의 환자를 2명의 평가자가 동시에 면담하였다. 수렴타당도와 변별타당도의 검증을 위해 총괄적인 임상 인상척도-강박장애(Clinical Global Impression-Obsessive Com-pulsive Disorder : CGI-OCD). 아동용 Leyton 강박 척도(Lryton Obsessional Inventory-Child Version : LOI-CV), 소아우울척도(Child Depression Inventory : CDI), 소아 상태-특성 불안척도(State-Trait Anxiety Inventory for Children : STAI-C)를 시행한다. 결과 : Cronbach's α값으로 평가한 내적 일치도는 0.86으로 높게 나타났다. CY-BOCS 전체 점수 강박사고, 강박행동 소척도 점수에 대한 군내 내적일치도는 각각 0.94. 0.94. 0.84로 우수한 평가자간 일치도를 보였다. CY-BOCS 전체 점수와 CGI-OCD 점수간의 상관관계는 매우 높게 나타났고(r-0.88), LOI-CY 총점과도 통계적으로 유의한 상관관계(r=0.51)가 관찰되었다. CY-BOCS 전체 점수와 STA-I-C의 상태불안 점수간에는 상관관계가 나타나지 않았고(r=0.25), 특성불안 점수(r=0.43) 및 CDI 점수(r=0.49)와는 유의한 상관관계를 나타냈다. 결론 : 본 연구결과, 한국판 CY-BOCS의 높은 타당도 및 신뢰도가 입증되었으며, 향후 강박 증상의 객관적인 평가 및 정량화를 위해 유용하게 사용될 수 있을 것이다. Objective : This study was carried out to evaluate the reliability and validity of the Korean form of the Children's Yale-Brown Obsessive Compulsive Scale(CY-BOCS). Method : Forty-two children with obsessive-compulsive disorder(OCD)(31 boys and 11 girls, aged 7 to 18 years) were assessed with CY-BOCS. Interrater agreement was assessed by two raters in subsample(n=20). discriminant and convergent validity were assessed by comparing CY-BOCS scores to Clinical Global Impression-OCD(CGI-OCD), Leyton Obsessional Inven-tory-Child Version(LOI-CV), State-Trait Anxiety Inventory for Children(STAI-C), and Child Depression Inventory( CDI ). Results : Internal consistency was high, measuring 0.86 for the 10 items and total score. The intraclass correlations for the CY-BOCS total, obsession, and compulsion scores were 0.94, 0.94, 0.84, suggesting excellent interrater agreement for subscale and total scores. The CY-BOCS total score showed highest correlation with CGI-OCD(r=0.88), and significant correlation with LOI-CV(r=0.51), Trait Anxiety score(r=0.43), and CDI scores(r=0.49), but it was not correlated with State-Anxiety score(r=0.25). Conclusion : The results of this study indicate that the Korean form of CY-BOCS is a reliable and valid scale for rating obsessive-compulsive symptom severity. KEY WORDS : Development · Rating scale · Obsessive-compulsive disorder · Reliability Validity.

과도 절삭에서의 절삭 공정 시뮬레이션

고정훈,조동우,윤원수,김주한 한국공작기계학회 2001 한국공작기계학회 춘계학술대회논문집 Vol.2001 No.-

In most of the existing mechanistic models, the cutting process simulation is often restricted to a single path machining operation under a fixed cutting condition. Complex cutting processes such as die or mold manufacturing, however, are performed under two- or three-dimensional multiple tool paths. Since the tool paths in CNC machining are composed of line and arc segments, transient cuts are frequently occured due to the multiple paths. Even in steady cuts, the width of cut is varied with each segment. In this regard, this paper deals with the development of process simulation system for transient cuts, where continuously changing cutting configuration is computed, and then the cutting forces are predicted.

교잡종 찰옥수수에 대한 연구 III : Ⅲ. 국내 옥수수 유전자원 수집종에 대한 주요 특성 분포

서정은,주현민,최윤표,홍범용,조양희,주정일,지희정,이희봉 충남대학교 농업과학연구소 2007 농업과학연구 Vol.34 No.2

2006년 국내 각 지역으로부터 수집된 재래종옥수수 유전자원을 관행방법에 의해 파종하고 주요특성별로 분포도를 살펴본 결과는 다음과 같다. 1. 수집된 유전자원에 대한 발아율은 대부분 80∼100%이상의 분포를 보였으나, 일부 수집계통에는 30% 미만의 극히 저조한 발아율을 보였다. 2. 수집자원에 대한 초기생육을 살펴보면 극히 생육이 저조한 것이 40% 정도를 보였고, 극히 우수한 자원은 3%미만으로 나타났다. 3. 간장은 대부분이 150∼199cm범위에 55%가 분포하고 있었으나, l00cm이하가 5%, 250cm이상이 8%로 나타나 수집종간에 큰 차이를 보였다. 4. 주당 분얼수는 1개 미만이 40%의 분포를 보였으나, 일부 수집종에서 2 내지 3개의 분얼수를 보이는 계통이 확인되었다. 5. 개화소요일수는 61∼64일의 범위에서 40%, 57∼60일의 범위에서 30%의 분포를 보였으며, 특히 일부 수집종의 경우 55일 이하의 극조생종도 10% 정도의 분포를 보였다. 6. 이삭길이는 대부분 11∼15cm범위에 60%가 포함되어 있으나, 일부계통에서 5cm미만이 2%, 16∼20cm의 이삭길이도 10%가 분포하였다. Germination ratio on the 300 collected genetic resources showed 80 to 100 percentage, but those of some accessions were very low as below 30 percentage. Early growth phase of most of these lines were very poor while some collected lines were very vigor. Range of stem height showed from 150 to 199cm, but that of some accessions showed below 100cm as five percentage and some of them was over 250cm as eight percentage. Number of tillers per plant appeared less one but some collected lines have two to three tillers per plant. In days to tasseling, some accessions showed more four per plant. Ear length of these accession showed above 60 percentage as 11 to 15cm, while that of some collected lines showed over 10 percentage as 16 to 20cm.

컬럼형 회분건조기를 이용한 벼의 건조에 관한 연구

변유량,최홍식,조형용,권윤중,김주봉 연세대학교 산업기술연구소 1984 논문집 Vol.16 No.1

The vertical column batch dryer which is suitable to Korean farm was constructed and dryer performance was investigated through field test. The effect of a drying air temperature and an airflow rate on the drying rate was studied, and an empirical drying equation was established. The average drying rate of paddy were 1.6-1.8%/hr at the air temperature of 43℃ and the airflow rates of 19.4 - 24.5 CFM/ft². The differences of grain moisture content between the inner and outer layer of vertical paddy bed were 0.5 - 0.9% The effect of a drying air temperature was larger at high airflow rate. At constant temperature, the drying rate was increased as an airflow rate was increased. The empirical drying equation could be expressed as followed: ??=0.9exp(??) Where K=3.22×?? The average whitening ratio of brown rice which was dried with column batch dryer was higher 0.6% than that of sun dried rice.

부하분산 및 결함허용을 제공하는 CORBA 기반 원격 회의 시스템 설계

성재철,임주혁,장우혁,조찬윤,최항묵 인제대학교 1999 仁濟論叢 Vol.15 No.1

인터넷 및 통신 기술의 발달에 따라 원격 회의 시스템이나 원격 교육, 가상 대학과 같은 응용에 대한 연구가 활발히 진행되고 있다. 이와 판은 시스템에 기존의 중앙 집중 방식을 사용할 경우에는 서버측의 부하가 모두 집중되어 전체 시스템에 영향을 미치게 될 수 있으므로 분산 시스템을 이용한 연구가 활발히 진행되고 있다. 본 논문에서는 이미지나 텍스트-파일과 같은 자료를 필요로 하는 원격 회의 시스템을 설계하고 Factory 객체와 관계형 통합 데이터 베이스를 이용하여 동적 부하 분산과 동적 결함 허용을 제공하는 시스템을 제안한다. As the technigues of the Interned and Communication are developed, the study about its applications such as Remote Conference system, Remote Education and Cyber University are lively progressing. When the centralized method is applied to those kinds of system mentioned above, the load is mostly occurred in the server side anaitcauas bad effect to the whole system. So the Study about an application such as Remote Conference system, Remote Education and Cyber University is considering using the distributed system. In this paper I would like design a Remote Conference System is soogetled, which needs sub data like images, text files and givers dynamic load balance and dynamic fault tolerance using Factory object and Relational Integrated Data Base.