• 제목/요약/키워드: source coverage

검색결과 167건 처리시간 0.026초

FDS를 이용한 교번식 미분무방식의 소화 성능 분석 (Analysis for fire suppression efficiency of intermittent water spray pattern with FDS)

  • 지문학;이병곤
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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    • pp.200-203
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    • 2008
  • Water mist fire suppression system utilizes the fire suppression features such as cooling of fire source, dilution of ambient oxygen, and shielding of radiation heat with the evaporation of microscopic water droplets. The momentum of water mist is relatively low and the infiltration of water mist to the fire source is not effective. In addition to lower penetration force, the evaporated water vapor is liable to decline to limited portion of fire source due to its light weight and sparse density. On the other hand, the cycling water mist system is expected to improve the penetration force of water mist as well as the dilution coverage capability with the stratified spray characteristics. At this paper we present the analyzed fire suppression capability of intermittent water spray pattern by use of FDS which is computational fire dynamics fire model. We expect this analysis shall be supportive to the development of the prototype of water mist nozzle.

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The Effect of Dietary Selenium Source and Vitamin E Levels on Performance of Male Broilers

  • Choct, M.;Naylor, A.J.
    • Asian-Australasian Journal of Animal Sciences
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    • 제17권7호
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    • pp.1000-1006
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    • 2004
  • Selenium and vitamin E are micronutrients essential for normal health and maintenance in poultry. They are necessary in preventing free radical damage to phospholipid membranes, enzymes and other important molecules. Two experiments were conducted in a semi-commercial environment to examine the effect of Se source and vitamin E level in diet on broiler performance and meat quality. Increasing vitamin E from 50 IU to 100 IU did not affect growth performance of broilers although the 24 h drip-loss was tended to be reduced (p=0.06). There was an interaction between vitamin E and the source of Se in glutathione peroxidase activity (GSH-Px) and Se concentration in excreta. Increasing vitamin E from 50 IU to 100 IU elevated GSH-Px and Se concentration in excreta by 42 IU/g Hb and 0.9 ppm for the organic Se group, respectively, but reduced GSH-Px and Se concentration in excreta by 16 IU/g Hb and 1.3 ppm for inorganic group, respectively. Vitamin E played no role in the feather coverage of the birds when scored on day 37. Organic Se is more effective in improving feather score and 24 h drip-loss, with a markedly higher deposition rate in breast muscle and a lower excretion rate in the excreta (p<0.05) compared to the inorganic Se source. Both vitamin E and the source of Se did not affect (p>0.05) the energy utilisation by birds.

TDEAT single source를 사용한 TiN막의 특성평가

  • 김재호;이재갑;박상준;신현국;황찬용
    • 한국진공학회지
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    • 제4권S1호
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    • pp.28-33
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    • 1995
  • TiN 박막은 저온(<$500^{\circ}C$), 저압(1Torr)에서 Tetrakis(diethylamido)titanium[TDEAT, Ti(NEt2)4]single precursor를 사용하여 증착하였다. 증차고딘 박막은 SEM(Scanning Electron Microscopy)으로 surface morphology와 step coverage를 측정하였고, TEM(Transmission Electron Microscopy)분석결과 microcrystalline의 TiN을 확인하였다. XPS(X-ray Photoelectron Spectroscopy)분석결과에 따르면 $200-500^{\circ}C$구간에서는 $\beta$-hydogen elimination에 의한 반응이 일어나고 $600-700^{\circ}C$구간에서는 thermal decomposition에 의한 반응이 일어나고 있음을 알 수 있다. Carbon과 oxygen의 농도는 AES(Auger Electron Spectroscopy)를 사용하여 측정하였으며 온도가 감소할수록 carbon의 농도가 감소하는 경향을 보여주고 있다.

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실손형 민간의료보험의 도입이 국민건강보험 재정에 미치는 영향 (Impact of Complementary Private Health Insurance on Public Health Spending in Korea)

  • 허순임;이상이
    • 보건행정학회지
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    • 제17권2호
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    • pp.1-17
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    • 2007
  • Limited coverage for health care services of National Health Insurance(NHI) in Korea has been ongoing policy issue but additional NHI financing through raising contribution or taxes in order to improve coverage faces substantial obstacles. Private health insurance(PHI) is often considered as an alternative financing source to improve coverage. Recent reform that attempted to stretch the role of PHI allowed life insurance companies to provide complementary PHI, indemnity plan which will pay for uncovered services by NHI and out-of-pocket spending for covered services. Although complementary PHI may relieve financial burden of patients, it may significantly raise NHI spending as well as total health expenditure since little out-of-pocket spending may increase utilization of health care. So far, there has not been enough discussion about concerns of potential adverse effect resulting from extended role of PHI. This study investigated potential increase of NHI spending followed by extension of complementary PHI through sensitivity analysis. The amount of NHI spending for services that would be covered by complementary PHI was calculated using 2005 NHI statistics and expected complementary PHI enrollment rate by age and sex. Expected utilization increases were obtained based on price elasticities$(-0.2{\sim}-0.5)$ from previous studies and expected coverage rate$(50{\sim}80%)$ of complementary PHI and then converted to monetary figures. Because coverage rate of complementary PHI has not been determined yet, we employed the sensitivity analysis using coverage rate of $50{\sim}80%$. Findings demonstrate that additional spending for health care services is expected to be $426{\sim}1,702$ billion won, corresponding amount payed by NHI $298{\sim}1,192$ billion won. In conclusion, since complementary PHI may raise NHI spending significantly, there should be an agreement whether this additional cost would be accountable and acceptable in our society. Potential inefficiency resulting from extended role of complementary PHI should be considered since public and private financing do not operate in isolation and there should be more discussion on proper role of PHI in Korea.

地衣類에 의한 精州市 大己汚染度 評價 (Estimation of Air Pollution by Lichens in Chongju)

  • 김재한;강숙경
    • 대한지리학회지
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    • 제36권3호
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    • pp.313-328
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    • 2001
  • 지의류는 대기오염도를 측성하는 대표적인 생물지표종이다. 본 연구는 청주시 내에 서식하고 있는 지의류 를 대기오염 지표종으로 활용하여 청주시 대기오염을 진단해 보고, 오염원과 거리와 풍향에 따라 지역별 오염도가 어떻게 달라지는지 살펴보았다. 그 결과 청주시 공단지역과 도심지역은 지의사막화 현상이 나타났고 SO$_2$농도가 0.03ppm 이상으로 추정되었다 또한 청주공단과의 거리기 먹어짐에 따라 대기오염이 낮아져 지의류의 종수와 피도가 증가하는 경향이 나타났다.

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목적 지향 콘콜릭 테스팅 (Goal-oriented Concolic Testing)

  • 정인상;박정규
    • 한국정보과학회논문지:소프트웨어및응용
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    • 제37권10호
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    • pp.768-772
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    • 2010
  • 콘콜릭 테스트는 높은 테스트 커버리지를 달성하기 위해 실제 프로그램 수행과 심볼릭 수행을 결합하여 테스트 데이터를 생성한다. CREST는 콘콜릭 테스팅을 구현한 대표적인 open-source인 테스트 도구이다. 그러나 현재 CREST는 기본적으로 프로그램의 모든 가능한 실행 경로들을 탐색하는 것을 목적으로 한다. 이 때문에 특정 분기 또는 블록만을 테스트하는 경우에는 비효율적일 수 있다. 이 논문에서는 프로그램 상의 한 분기 또는 블록을 주고 이률 실행할 수 있는 테스트 데이터를 생성하는 목적 지향 콘콜릭 테스트 방법을 제안한다.

A Study on Cooperative Communication using Space-Time Codes

  • Pham, Van-Su;Mai, Linh;Lee, Jae-Young;Yoon, Gi-Wan
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2007년도 춘계종합학술대회
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    • pp.87-90
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    • 2007
  • In cooperative communication systems, the source terminal transmits signal to the destination terminal with the aid of partner terminals. Therefore, the source terminal obtains extra spatial diversity gain. As a result, its performance is enhanced in term of higher achievable transmission rate, the larger coverage range, and the lower bit-error-rate (BER). Space-time codes (STCs) have been applied to cooperative communication systems in distributed fashion, in which the signal is spatially time exploited to obtain gains analogous to those provided by STCs. In this work, we consider the application of orthogonal Space-time Block Codes (OSTBCs) to the cooperative communication systems to further achieve higher diversity gain. The advances of the proposed approach are verified via computer simulations.

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Release of AKARI/FIS Bright Source Catalogue ${\beta}-2$

  • 정웅섭
    • 천문학회보
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    • 제35권1호
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    • pp.41.2-41.2
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    • 2010
  • The infrared astronomy satellite AKARI/FIS (Far-Infrared Surveyor) performed all-sky survey in 4 Far-IR bands (50 - 200${\mu}m$ range). It observed around 94% of the whole sky twice or more with a higher spatial resolution and a wider wavelength coverage than that of previous all-sky mission, IRAS. The AKARI/FIS bright source catalogue ${\beta}-2$ is the second released version which included around 290,000 point sources. It provides us with more reliable position and flux information, and around 4 times larger number of sources compared with the first version of catalogue. The sensitivity limit at $90{\mu}m$ band is 0.6 Jy and the estimated flux uncertainty is 20-35% for bright sources. The catalogue will be open to public in this year after the improvement of accuracy, reliability and completeness.

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Submillimeter galaxies in the AKARI North Ecliptic Pole survey field

  • Lee, Dongseob;Kim, Yeonsik;Shim, Hyunjin
    • 천문학회보
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    • 제44권2호
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    • pp.74.3-74.3
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    • 2019
  • SCUBA-2 North Ecliptic Pole survey, one of the ongoing JCMT large programs, is designed to obtain 850 ㎛ imaging data over ~4 deg2 around the NEP based on the AKARI NEP-Wide survey. By August 2019, the program is 50 % complete in terms of observing time, increasing the submillimeter coverage by a factor of 2 with the comparable depth. The rms measured in the deepest center is 0.92 mJy/beam, slightly above the 850 ㎛ confusion limit. With 4 σ detection, the source count is 50 % complete at 9 mJy. The surface density of submillimeter galaxies at this flux limit is 200 deg-2. Multi-wavelength identification of the 850 ㎛ sources was done through the likelihood analysis based on the far-infrared (250-500 ㎛), mid-infrared (18 ㎛), near-infrared (2-4 ㎛), and optical (i-band) source catalog. We are going to present morphologies and physical properties of 850 ㎛ selected submillimeter galaxies with the help of ancillary multi-wavelength datasets over the NEP area.

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Wikipedia as an Online Health Information Source: Consumers' Satisfaction with Information Quality

  • Boryung Ju;Yoonhyuk Jung;John Paul Bourgeois
    • Journal of Information Science Theory and Practice
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    • 제12권2호
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    • pp.36-48
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    • 2024
  • For consumers making health decisions, Wikipedia is a popular source for health information. This study investigated major factors influencing consumer satisfaction with Wikipedia medical/health articles. Using a crowdsourcing method, data were collected from 322 adults who read/edit English Wikipedia medical/health articles and reside in the US. The results showed that the presentation of information was the most influential factor. Trustworthiness was the second most important factor for consumer satisfaction with the quality of information, followed by reliability, and topic coverage. Study participants did not consider other factors such as accuracy and currency to be crucial factors. Moderating effects of the control variables such as editing experience with Wikipedia articles, gender, and age were also examined to enhance the internal validity of the study. Implications for the Wikipedia editor community and researchers, and directions of future research are presented.