• 한국정보통신학회논문지
• /
• 제8권2호
• /
• pp.310-323
• /
• 2004

In this paper, we extend the multiple time scale control framework to window-based congestion control, in particular, TCP This is performed by interfacing TCP with a large tine scale control nodule which adjusts the aggressiveness of bandwidth consumption behavior exhibited by TCP as a function of "large time scale" network state. i.e., conformation that exceeds the horizon of the feedback loop as determined by RTT Our contribution is threefold. First, we define a modular extension of TCP-a function call with a simple interface-that applies to various flavors of TCP-e.g., Tahoe, Reno, Vegas and show that it significantly improves performance. Second, we show that multiple time scale TCP endows the underlying feedback control with preactivity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay-bandwidth product in broadband wide area networks. Third, we investigate the influence of three traffic control dimensions-tracking ability, connection duration, and fairness-on performance. Performance evaluation of multiple time scale TCP is facilitated by a simulation bench-mark environment which is based on physical modeling of self-similar traffic.

• 한국통신학회논문지
• /
• 제33권5B호
• /
• pp.344-355
• /
• 2008

본 논문에서는 차등서비스 망의 성능 평가 문제를 다룬다. 성공적인 성능 평가를 위하여 적절한 트래픽 모델에 의하여 네트워크상의 실제 트래픽을 정확히 나타낼 수 있는 능력이 필수 요소이다. 실제 트래픽 측정의 성질에 대한 많은 연구 결과는 웹과 텔넷, P2P 트래픽을 포함하여 인터넷 트래픽에 대한 장기간-의존성을 증명하였다. 장기간 의존성은 자기유사성에 의하여 효과적으로 표현될 수 있다. 본 논문에서는 중첩된 On-Off 소스 모델, FFT-FGN 모델과 RMD 모델에 대한 특성 분석을 기반으로, 중첩된 On-Off 소스 모델을 이용하여 자기유사트래픽 발생기를 설계하고 구현한다. 생성된 트래픽의 자기유사성은 TCPdump 데이터의 패킷 도착 간격을 조사하여 확인하였다. 또한 구현된 트래픽 발생기를 차등서비스 망의 성능평가에 적용하여 On/Off 모델의 $\alpha$ 값에 대한 성능이 영향과, CBQ(Class-Based Queueing)에 의한 EF(Expedited Forwarding)/BE(Best Effort) 클래스 트래픽의 성능을 관찰한다.

• 한국산학기술학회:학술대회논문집
• /
• 한국산학기술학회 2006년도 춘계학술발표논문집
• /
• pp.294-297
• /
• 2006

Measurement of network traffic have shown that the self-similarity is a ubiquitous phenomenon spanning across diverse network environments. In previous work, we have explored the feasibility of exploiting the long-range correlation structure in a self-similar traffic for the congestion control. we show that a multiple time scale TCP endows the underlying feedback control with proactivity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay-bandwidth product in broadband wide area networks. Third, we investigate the influence of the three traffic control dimensions-tracking ability, connection duration, and fairness-on performance.

• 대한치과교정학회지
• /
• 제47권1호
• /
• pp.11-20
• /
• 2017

Objective: This randomized controlled trial aimed to compare the stability of mandibular arch orthodontic treatment outcomes between passive self-ligating and conventional systems during 6 months of retention. Methods: Forty-seven orthodontic patients with mild to moderate crowding malocclusions not requiring extraction were recruited based on inclusion criteria. Patients (mean age $21.58{\pm}2.94years$) were randomized into two groups to receive either passive self-ligating ($Damon^{(R)}$ 3MX, n = 23) or conventional system (Gemini MBT, n = 24) orthodontic treatment. Direct measurements of the final sample comprising 20 study models per group were performed using a digital caliper at the debonding stage, and 1 month, 3 months, and 6 months after debonding. Paired t-test, independent t-test, and non-parametric test were used for statistical analysis. Results: A significant increase (p < 0.01) in incisor irregularity was observed in both self-ligating and conventional system groups. A significant reduction (p < 0.01) in second interpremolar width was observed in both groups. Mandibular arch length decreased significantly (p = 0.001) in the conventional system group but not in the self-ligating system group. A similar pattern of stability was observed for intercanine width, first interpremolar width, intermolar width, and arch depth throughout the 6-month retention period after debonding. Comparison of incisor irregularity and arch dimension changes between self-ligating system and conventional system groups during the 6 months were non-significant. Conclusions: The stability of treatment outcomes for mild to moderate crowding malocclusions was similar between the self-ligating system and conventional system during the first 6 months of retention.

• 대한물리의학회지
• /
• 제8권1호
• /
• pp.19-27
• /
• 2013

PURPOSE: The purpose of this study is to look into relationship between image of physiotherapist and self-esteem of physiotherapy students and desirable image of physiotherapists offer to establish basic materials. METHODS: The subjects of this study are consist of 603 students of department of Physical therapy university and college in Busan and Kim-hae. Data are collected from June 9 to July 9 in 2011 by structured questionnaires. RESULTS: The result are as follows. 1. at the physiotherapist image score, the highest score question is "Physiotherapist is specialist"(3.45) and the lowest score question is "Physiotherapist is treated samely with doctor"(2.15). 2. at the self-esteem score, the highest score question is "I think that I am at least as valuable as others"(3.37) and the lowest score question is "I can be poorly sometimes"(2.81). 3. at the static results of physiotherapist image score gap by general characteristics, there are significantly different in gender(t=2.27, p=.02), similar profession distinction(t=4.30, p=.00), major satisfaction(t=5.74, p=.00), school system (t=-2.54, p=.01). 4. at the static results of self-esteem score gap by general characteristics, there are significantly different in years (f=5.14, p=.00), gender(t=4.09, p=.00), religion(f=2.87, p=.04), similar profession distinction(t=3.97, p=.00), major satisfaction(t=4.26, p=.00). 5. at the static results of good reputation of physiotherapists increase self-esteem of physiotherapy students score question are significantly different(r=0.53, p=.00). CONCLUSION: Accordingly, these results of this study that there is a very correlation between image of physiotherapist and self-esteem of physiotherapy students. Therefore, good reputation of physiotherapists increase self-esteem of physiotherapy students.

• 한국육종학회지
• /
• 제41권2호
• /
• pp.154-157
• /
• 2009

배는 배우체 자가 불화합성을 보이며, 이것은 단일 유전자좌의 복대립 유전자에 의하여 제어된다. '원교 나-자수정 2호'는 농촌진흥청 국립원예특작과학원에서 고품질 조생종 '원황'에 '92-18-79' (오사이십세기 자식계통, ${S_4}^{sm}{S_4}^{sm}$)를 2001년에 교배하여 얻은 계통 중에 자가 결실성이며 품질이 우수하여 중간모본으로 선발되었다. 만개기는 '오사이십세기'보다 1일 정도 빠르고 '원황'과는 유사하다. 수세는 중, 수자는 반개장형이다. 검은별무늬병(Venturia nashicola)에는 '오사이십세기' 정도로 약하고 검은무늬병(Alternaria kikuchiana)에는 '원황'과 같이 강하다. 자가 결실률은 65.7%로 안정된 자가 결실률을 보였다. 만개후 성숙기까지는 148일로 '오사이십세기'보다는 11일가량 빠르며, '원황'보다는 11일 정도 늦다. 과형은 원편원이고 과피는 황갈색이다. 평균 과중은 445 g이며 당도는 $13.3^{\circ}Brix$로 높고 과즙은 풍부하며 석세포는 적다.

• 정보처리학회논문지:소프트웨어 및 데이터공학
• /
• 제12권11호
• /
• pp.493-504
• /
• 2023

대한민국은 지진 판의 경계로부터 멀리 떨어진 지역에 있으며, 이러한 지역에서 발생하는 판 내부 지진은 판 경계부 지진과 비교하면 일반적으로 규모가 작고 발생빈도도 낮다. 그럼에도 불구하고 과거 2년부터 1904년 사이 한반도에서 발생했던 지진과 최근 한반도 지진을 관측한 이래에 발생한 지진을 조사 및 분석한 결과 진도 규모 9까지 이르는 것으로 나타났다. 본 논문에서는 한반도에서 발생한 지진과 통계적 자기 유사성과의 관계를 분석하기 위해서 국립기상연구소에서 발표한 「한반도 역사지진 기록 (2년~1904년)」을 이용한다. 또한 본 논문을 통해서 해결한 문제는 한반도에서 발생한 지진데이터와 통계적 자기 유사성과 시각화의 관계 연구를 처음으로 규명하였으며, 그 결과 한반도 지진의 자기 유사성 정도를 판단하는 3가지 정량적인 추정방법으로 측정한 결과 자기 유사성 파라메터 H 값(0.5 < H < 1)이 0.8이상으로 자기 유사성 정도가 높은 것으로 나타났다. 그리고 그래프의 시각화를 통해 지진이 어느 지역에서 많이 발생했는지를 쉽게 파악할 수 있고, 향후 지진 발생시 피해를 예측하고 재산과 인명 피해를 최소화할 수 있는 예측 시스템 개발과 지진 데이터 분석 및 모델링 연구에 활용될 수 있을 것으로 보인다. 뿐만아니라 본 연구결과를 토대로 자기 유사성 프로세스는 지진활동의 패턴과 통계적 특성을 이해하고, 유사한 지진 사건을 그룹화하고 분류하는데 도움을 줄 수 있으며, 지진 활동에 대한 예측, 지진 위험 평가 및 지진 공학 관련 연구에 활용될 것으로 예상된다.

• 복식
• /
• 제50권2호
• /
• pp.151-165
• /
• 2000

This study was to find out clothing design preferences, according to the clothing self-image of elderly women and to grasp the variety on clothing of elderly women and thereby to help in merchandise production planning and putting the brands into markets and to provide data for establishing a sales strategy a d to itemize women with the goods which can satisfy the desire and taste of consumer groups in the quality market. For this purpose , various researches as above were conducted .The object of this study was a total of 488 elderly women above full 55 from an elderly women and who lived in downtown Pusan. The data were analysed by using MANOVA, ANOVA , factors analysis and frequency analysis, and the Cronbach α was also applied . The conclusions made based on the theoretical background and the result of questionnaire surveys are as follows ; 1. The realistic self-image of clothing showed a similar pattern by age. 50's and 60's showed little difference by item but 70's was greater in variation between items compared to 60's. The response to each item was that most people answered "common" and they showed a pattern that responded low only in items of 'colorful' , individualistic', 'susceptible to fashion'. A similar pattern was shown by age band also in the ideal self-image and the response to each item appeared higher than in the realistic self-image , and also in items of 'colorful', 'individualistic ' , 'susceptible to fashion' the response appeared low and showed a unity. 2. The results of clothing design preferences examined on the self-image according to age are as follows ; 1) Fro jacket in the realistic self-image , 50's and 60's preferred 'tailed collar' , 'set-in sleeve', 'hips long' and 'plain jacket' and 70's agreed to the design preferences in the items except 'open collar' and also in the idealistic self-image , the degree of preference was same. 2) For skirt in the realistic self-image , 50's and 60's preferred 'tight skirt', 'normal length' , 'plain skirt' and it was appeared that 70's preferred 'pleat skirt' , 'medium length' , 'plain skirt'. Also in the idealistic self-image , the degree of preference was same. 3) For blouse in the realistic self-image, 50's preferred 'open collar', 'round neck line' , 'long set-in sleeve' , 'plain separation belt', 'open front', 'zipper' ad 60's agreed to the favorite designs with 50's except puff sleeve, and 70's appeared to prefer fastening buttons without belt. In the designs preferred in the idealistic self-image, 50's agreed with 50's of the realistic self-image and for 60's , the designs except puff sleeve type and no belt type agreed to 50's and 70's except puff sleeve agreed with 70's of the realistic self-image in their design preferences.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• 제6권1호
• /
• pp.91-107
• /
• 2002

This paper presents two new self-scaling variable-metric algorithms. The first is based on a known two-parameter family of rank-two updating formulae, the second employs an initial scaling of the estimated inverse Hessian which modifies the first self-scaling algorithm. The algorithms are compared with similar published algorithms, notably those due to Oren, Shanno and Phua, Biggs and with BFGS (the best known quasi-Newton method). The best of these new and published algorithms are also modified to employ inexact line searches with marginal effect. The new algorithms are superior, especially as the problem dimension increases.

• 한국연소학회:학술대회논문집
• /
• 한국연소학회 2012년도 제44회 KOSCO SYMPOSIUM 초록집
• /
• pp.83-85
• /
• 2012

Experimental study in coflow jet flames has been conducted to investigate the effects of adding $N_2$, $CO_2$ and He to coflowing air-side in self-excitations. Differences in the behaviors between buoyancy-driven and diffusive-thermal self-excitations with similar frequency range are explored and discussed in laminar coflow jet flames.