• 제목/요약/키워드: Window-effect

검색결과 741건 처리시간 0.025초

데이터센터 네트워크의 패킷단위 스케줄링에서의 DCTCP 성능 (Performance of DCTCP with per-packet scheduling in data center networks)

  • 임찬숙
    • 한국인터넷방송통신학회논문지
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    • 제18권1호
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    • pp.15-21
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    • 2018
  • 데이터센터 네트워크의 자원을 효율적으로 활용하여 플로우들의 지연시간을 줄이기 위해서는 플로우 단위의 스케줄링보다는 패킷단위의 스케줄링이 적합하다. 따라서 최근에는 데이터센터 네트워크의 다중경로를 활용하여 패킷단위로 스케줄링을 수행하는 방식이 많이 제안되었다. 그러나 이로 인해 발생하는 순서 바뀐 패킷들이 표준 TCP 성능에 미치는 부정적인 영향을 줄이기 위해, 대부분의 방식들은 TCP 아래 계층에서 순서를 다시 맞추는 등의 보완방안을 필요로 한다. 본 논문에서는 데이터센터 네트워크의 대표적인 전송계층 프로토콜인 DCTCP가 다중경로상의 패킷단위 분산과 함께 사용될 때 어떤 성능을 보이는지 모의실험을 통해 조사한다. 모의실험 결과는 DCTCP가 큐의 길이를 짧게 유지할 수 있지만 혼잡신호에 따라 혼잡윈도우를 줄이는 방식 때문에 오히려 공평성 등의 측면에서는 기존 TCP보다도 낮은 성능을 가짐을 보여준다.

커튼월 스팬드럴용 진공유리의 열파손에 대한 비교실험 (A Comparative Experiment on Thermal Stress Failure of Vacuum Glazing applied in Curtain Wall at Spandrel area)

  • 김승철;윤종호;신우철;안정혁
    • KIEAE Journal
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    • 제16권3호
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    • pp.121-128
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    • 2016
  • Purpose: The vacuum glazing should constantly retain the gap in vacuum state to maintain high thermal performance. To do so, pillars are used to prevent the glazing from clinging to each other by the atmospheric pressure and therefore surface of the vacuum glazing is consistently affected by residual stress. The vacuum glazing could be applied to curtain wall systems at spandrel area to fulfill a rigorous domestic standard on U-value of the external wall. However, this can lead to high glazing temperature increase by heat concentration at a back panel and finally thermal stress breakage. This study experimentally determined weakness of the vacuum glazing systems on the thermal stress breakage and investigated effect of the residual stress. Method: The experiment first built two scale-down mock-up facilities that replicate the spandrel area in curtain wall, and then installed single low-e glass and vacuum glazing respectively. The two mock-up facilities were exposed to outside to induce the thermal stress breakage. Result: The experiment showed that the temperature occurred the thermal stress breakage was $114.4^{\circ}C$ for the single low-e glass and $118.9^{\circ}C$ for the vacuum glazing respectively. The result also showed the vacuum glazing reached the critical point earlier than the single low-e glass, which means that the vacuum glazing has high potential to occur the thermal shock breakage. In addition, the small temperature difference between two glazing indicates that the residual stress scarcely affects breakage of the vacuum glazing.

CdS 박막의 boron doping에 따른 CdS/CdTe 태양전지 특성 (The Effect of Boron Doped CdS Film on CdS/CdTe Solar Cell)

  • 이호열;이재형;김정호;박용관;신재혁;신성호;박광자
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 D
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    • pp.1370-1372
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    • 1998
  • Boron doped CdS films were prepared by CBD(Chemical Bath Deposition) method using boric acid ($B_3HO_3$) as donor dopant source, and their properties were investigated. As-grown CdS films were highly adherent and specularly reflective. Boron doped CdS film which was fabricated under the condition of 0.01 $B_3HO_3/Cd(Ac)_2$ mole ratio, exhibited the lowest resistivity of $2{\Omega}cm$ and the highest optical bandgap of 2.41eV. Also, CdS/CdTe solar cells were fabricated with various doping concentration of CdS films. Using optimized CdS film as the window layer of CdS/CdTe solar cell, the characteristics of the cell were improved. ( $V_{oc}$=610mV, $J_{sc}$=37.5mA/cm, FF=0.4, $\eta$=9.1% )

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CAI를 이용한 어린이 성희롱/성폭력 예방교육 효과 (The Effect of Computer-Assisted Instruction(CAI) through the Multimedia CD-ROM on the Prevention of Child Sexual Abuse)

  • 배정이
    • 한국간호교육학회지
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    • 제10권2호
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    • pp.239-251
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    • 2004
  • The purpose of this study was to find out the effects of education for prevention of child sexual abuse (rape, sexual assault, sexual harassment etc.) of children in elementary school students. Incidences of sexual abuse in Korea is ranked 3rd in the world. Sexual abuse of children, particularly, is one of the most serious crimes that affect both the victimized children and their family. The issue related to sexual abuse of children has been ignored, and there is a lack of systematic education to prevent sexual abuse of children either for children or their parents. Furthermore, lack of knowledge and poor attitude of teachers limit their capability to provide education for sexual abuse prevention to the children. The education for teachers may change their knowledge of the sexual abuse and their attitude toward it and improve their capability in helping children. 223 Korean elementary school students participated in this study. Research design was One group pretest-posttest design. The education given to the subjects included 4 hours through the multimedia CD-ROM on the prevention of child sexual abuse. The education program was developed based on a survey. School- aged- children, parents, and teachers were interviewed to reveal their educational needs based on their experiences related to sexual abuse. This program includes such as safety education, crisis management, resource person(s), and phone numbers of available hospital. Data was collected before, during and after the education was given to the subjects, to assess their knowledge and attitude toward child sexual abuse. Two instruments were used in this study. Using Cronbach's ALPHA validity and reliability of 2 instruments were tested. The analysis of the data was done with Window SPSS 10.0 for descriptive statistics, t-test and ANOVA. The results of this analysis were as follows : 1. After education, the score of school nurses knowledge was higher than before(t= -4.677, p=0.000). 2. After education, the score of school nurses attitude was not higher than before (t=0.131, p=0.896). The findings from this study will provide an intervention strategy for prevention of sexual abuse in children.

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소집단 역동을 이용한 간호대학생의 의사소통 훈련프로그램의 효과 (The Effect of Small Group Based Communication Training Program on the Competency of Communication and the Human Relationship in Nursing College Students)

  • 원정숙;신현숙
    • 동서간호학연구지
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    • 제14권2호
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    • pp.60-66
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    • 2008
  • Background: Communication training in nursing college students is an integral part of the development of their competency in dealing with patients. However, the traditional lecture style of training delivery may not be desirably effective. Purpose: This study investigated the effects of a communication training program utilizing a small group dynamic on the communication competency and human relationships in nursing college students. Methods: One hundred twenty six freshmen in a university in Seoul participated in this study. The instruments of communication competency (Primary Communication Inventory) and human relationships (Relationship Change Scale) were used at the beginning and conclusion of the training period. Eighty-three students from two nursing classes were assigned to the experimental groups and 43 students from other classes were assigned to the control groups. Each of the 11 small groups was composed of 7 or 8 students. The weekly program that ran during the 2007 fall semester from October 1st to December 11th consisted of effective communication strategies including therapeutic communication skills, Johari's window, empathy, active listening, and transactional analysis. Results: The experimental group of students reported significantly greater improvement in communication competencies, specific nonverbal competencies, and human relationships compared with the control group. Specifically, the experimental students demonstrated greater improvement in nonverbal communication competencies and satisfaction, communication, and awareness of human relationships. Conclusions: Small group based communication training can be an effective alternative method of communication education for college nursing students.

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와파린과 상호작용하는 한약재에 대한 고찰 (Overview of the Interaction between Warfarin and Korean Herbal Medicine)

  • 이인;박상무;박승찬;김도형;조민경;한창우;권정남;홍진우
    • 대한한방내과학회지
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    • 제33권2호
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    • pp.160-171
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    • 2012
  • Background and Objective : Warfarin is the standard anticoagulation treatment for atrial fibrillation, venous thromboembolism (VTE), and mechanical heart valves. Close monitoring of the International Normalized Ratio (INR) is required due to the drug's very narrow therapeutic window. Many factors can affect INR levels. Drug and food interactions are frequently cited as causes of adverse events with warfarin. We discussed interactions between herbs and warfarin studied in this research. Methods : In this review, PubMed was used to search medical journals. Keywords "warfarin AND interaction" were applied. Results : 55 articles were included. The possibility of correlation between warfarin and single herbal medicines such as Salviae Miltiorrhizae Radix, Angelicae Gigantis Radix, Ginseng Radix Alba, Lycii Fructus, Ginkgo Folium, Menthae Herba, Trigonellae semen was suggested. Furthermore, some herbal compounds interacting with warfarin were reported. The conclusion of studies reporting the effect of herbal medicine on warfarin were controversial due to small size or quality of research. Conculsions : We suggest that we should prescribe therapeutic herbal medicines to patients using warfarin more carefully and do INR follow-up regularly.

철근 콘크리트 부재의 균열 깊이 측정을 위한 표면파 투과기법의 적용 및 개선 (Application and Improvement of Surface Wave Transmission Technique for Measuring the Crack Depth in Reinforced Concrete Members)

  • 민지영;김재홍;곽효경;윤정방
    • 비파괴검사학회지
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    • 제28권2호
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    • pp.164-176
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    • 2008
  • 기존 사회기반 시설의 안전성 평가를 위해서는, 콘크리트 부재에 존재하는 균열에 대해 정량적인 평가가 필요하다. 이 논문에서는 균열의 깊이를 측정할 수 있는 비파괴검사 중 표면파 투과기법에 대해 고찰하였다. 특히, 콘크리트 부재 내부에 위치하는 철근이 표면파에 미치는 영향을 분석하여, 표면파 투과기법을 통한 균열깊이 추정 시 철근에 의해 발생하는 오차가 크지 않음을 확인하였다. 또한, 콘크리트 부재의 형상에 따라 발생하는 여러 반사파의 영향을 최소화하기 위해 치적의 윈도우 크기를 제안하여 그 타당성을 검증하였다.

펄스형 고전압 전원에 의한 선전리 현상의 관측과 질소레이저의 동작 특성 (Observation of the Preionization effect and Operational Characteristics of a Nitrogen Laser by a Pulse type high Voltage Power Supply)

  • 이봉연
    • 한국광학회지
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    • 제17권1호
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    • pp.60-67
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    • 2006
  • 본 논문에서는 I자형과 U자형의 변압기를 각각 사용한 펄스형 고전압 전원에 의해 대기압에서 동작되는 파장 337.1 nm인 질소레이 저의 방전간극과 레이저 관에 각각 광섬유를 설치하고, 이를 통해 나오는 빛을 핀 다이오드를 이용하여 선전리 현상을 직접 관측하고 출력특성을 조사하였다. 레이저 출력이 안정되고 높아질수록 선전리 현상을 뚜렷이 관측할 수 있었고, 레이저 출력은 I자형 변압기보다는 U자형의 변압기를 사용하였을 때 높은 출력과 안정성을 얻었으며, 또한 펄스 방전의 예비동작 시간도 U자형이 1/3 정도 짧았다. U자형의 변압기를 사용하고 출력창의 반사율 $40\%$, 반복율 10 Hz, 레이저 관내에서 질소기체의 유동률이 4 ${\iota}$/min, 방전간극 내에서 질소기체의 유동율이 1500 cc/min, 방전간극 전극 거리 3.0 mm, 레이저 관 내 전극거리 5.0 mm 일 때, 안정성이 $2.7\%$$36{\mu}J$의 출력을 얻었다.

인터랙션 문제에 대한 선택의 문화적 차이 (Cultural Differences of Choice on Interaction Problem)

  • 연명흠
    • 감성과학
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    • 제13권4호
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    • pp.711-720
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    • 2010
  • 이 연구는 인터랙션 선택 문제에서 국가(문화), 세대, 성별, 개인주의-집단주의 등의 변수에 따라 선택에 차이가 발생하는지를 파악하고, 나아가 그 차이의 원인을 고찰하고자 한 연구이다. 본 설문에서 조사한 인터랙션 선택문제는 휴대전화 SMS보관함의 삭제버튼을 눌렀을 때의 화면디자인, 소프트웨어 설치의 위험성을 경고하는 인터넷 경고창에 대한 대응, 수프 메이커 컨트롤패널의 유형 및 정보표현방식 선택으로 구성되었다. 한국인 639명을 조사한 1차조사와 중국, 일본, 네덜란드인 총 784명을 조사한 2차조사 데이터를 토대로, 교차분석 및 카이검정을 실시하였다. 그 결과 휴대전화 SMS보관함 삭제문제에서는 일본인은 '아니오'를 네덜란드인은 '예'를 더 많이 선택해, 불확실성 회피 성향이 인터랙션 선택문제에 영향을 미침을 시사했다. 인터넷 경고창 문제에서는 나이든 세대에 비해 젊은 세대가, 여성에 비해 남성이 적극적으로 설치하는 경향을 보였다. 컨트롤패널의 유형 선택에서 네덜란드인은 디지털형보다 아날로그형을 상대적으로 더 선호했다. 컨트롤패널의 정보표현방식 선택에서는 나이든 세대일수록, 또한 개인주의일수록 문자표현을 상대적으로 더 선호했다. 여러 변인들 중 국가(문화)가 가장 큰 차이를 보여 가장 의미있는 변수임을 확인하였다.

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일 지역 근로자의 건강증진행위 예측모형 (Prediction Model for Health Promotion Behaviors of the Workers in an Area)

  • 이미자
    • 지역사회간호학회지
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    • 제15권1호
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    • pp.102-109
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    • 2004
  • Purpose: The purpose of this study was to confirm a structural model for health promotion for industrial workers. Methods: Data was collected by questionnaires from 294 industrial workers at a food manufacturing factory. The data collected were analyzed through SAS 8.1 and Window LISREL 8.12a. Results: 1. The result of the test showed that the measurement of fitness was $x^2$=(삭제) 443.35, $x^2$/df 5.3415, GFI .86, AGFI .75, RMR .060, NFI .95, NNFI .93, CN 77.58, and those other than NFI and NNFI did not well fit into the practical data. 2. 15 out of 29 paths in a constructed model were statistically significant. 3. The measurements for total fitness in the modified model were $x^2$= (삭제) 146.51, $x^2$/df 1.8546, GFI .95, AGFI .91, RMR .042, NFI .98, NNFI .99, CN 223.44, all of which showed fitness in good shape to the practical data. 4. The result of the study for the modified model indicated that perceived self efficacy had the most significant direct effect on health promotion behaviors, and self esteem, perceived benefits of action, interpersonal influences, commitment to a plan of action were important factors having influences on them. Conclusion: The derived model in this study is considered appropriate in explaining and predicting health promoting behavior of industrial workers. Therefore, it can effectively be used as a reference model for further studies and suggested implication in nursing practice.

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