• 한국환경보건학회지
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• 제33권4호
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• pp.283-292
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• 2007

Atmospheric concentrations of radon had been continuously observed in Seoul, Korea since December 1999, as a tracer for long-range transport of air pollutants from China continent to Korea. In order to study radon as a tracer of long-range transport, it is important to know information about the atmospheric distribution and variation of radon concentration and its time variation. Atmospheric radon concentration are measured with electrostatic radon monitor(ERM) at Hanyang University located in Eastern area of Seoul. Air sample is taken into a vessel of ERM, and alpha particles emitted by radon daughters $Po^{218}$ are detected with ZnS(Ag) scintillation counter. Hourly mean concentrations and hourly alpha counts are recorded automatically. The major results obtained from time series observation of atmospheric radon were as follows : (1) The mean of airborne radon concentration in Seoul was found to be $7.62{\pm}4.11\;Bq/m^3$ during December $1999{\sim}January$ 2002. (2) The hourly variation of radon concentrations showed the highest in 8:00AM ($8.66{\pm}4.22\;Bq/m^3$) and the lowest in 3:00AM ($6.62{\pm}3.70\;Bq/m^3$) and 5:00AM ($6.62{\pm}3.39\;Bq/m^3$). (3) the seasonal variation of radon concentrations showed higher during winter-to-fall and lower during summer-to-spring. (4) Correlation between airborne radon concentration and the meteorological factors were -0.21 for temperature, 0.09 for humidity, -0.20 for wind speed, and 0.04 for pressure. (5) The mean difference of airborne radon concentration between Asian dust ($5.36{\pm}1.28\;Bq/m^3$) and non-Asian dust ($4.95{\pm}1.49\;Bq/m^3$) phenomenon was significant (p=0.08). We could identify time series distribution of radon concentration related meteorological factors. In addition, radon can be considered a good natural tracer of vertical dispersion and long-range transport.

• 한국시뮬레이션학회논문지
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• 제29권3호
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• pp.57-72
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• 2020

북한 장사정포 위협에 대응하기 위해서는 한국형 장사정포요격체계 구축이 필요하다. 본 연구는 북한 장사정포의 위협에 대응하기 위한 요격체계의 운영개념 정립과 운용 효과도 프로세스를 개발하는 것을 목적으로 하였다. 먼저 장사정포요격체계의 운영개념을 설정하고, 다대다 교전 상황에서 효과도의 개념과 이를 도출하기 위한 프로세스를 수립하였으며, 이를 바탕으로 실제 효과도를 분석하기 위한 도구를 개발하였다. 그리고 다대다 교전 상황에서 효과도에 영향을 미치는 요인을 알아보기 위하여 탐지자산, 교전통제, 발사대 성능 등 다양한 변수들을 조합하여 시뮬레이션 실험을 수행하고 분석하였다. 그 결과 유도탄 성능 외에도 탐지자산, 교전통제소 성능이 요격률과 방어성공률에 얼마나 영향을 미치는지를 알 수 있었다. 이러한 연구 결과는 향후 무기체계 개발에 있어서 다대다 교전 상황에서의 효과도 측면에서 중요한 성능 지표를 이해하고 달성하고자 하는 수준의 방어성공률을 위해 필요한 각 요소의 개발 방향과 목표값 설정을 판단하는 데에 활용될 수 있을 것이다.

• 대한수학회지
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• 제35권3호
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• pp.741-753
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• 1998

Let G(*) be a Borel function applied to a stationary long memory sequence {X$_{i}$} of standard Gaussian random variables. Focusing on the process {G(X$_{i}$)}, the present paper establishes the almost sure representation for the empirical quantile process, that is, Bahadur's representation, and for the empirical process with respect to sample mean. Statistical applications of the representations are also addressed.sed.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2000년도 춘계학술대회 논문집
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• pp.133-138
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• 2000

In this paper some shapes of the FBW cross sections were examined to improve the performance of FBW for the long wave. Trapezoidal section and prominence section were examined. Linear potential theory is used and the boundary element method is use for numerical computation. Proper choice of the pontoon geometry may improve the transmission coefficient in the long wave range for a given wave period.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 춘계학술대회 논문집
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• pp.683-684
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• 2008

• 한국생산제조학회지
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• 제18권3호
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• pp.285-293
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• 2009

Thermal infrared cameras have been conducted actively in various application areas, such as military, medical service, industries and cars. Because of their characteristic of sensing the radiant heat emitted from subjects in the range of long-wavelength($3{\sim}5{\mu}m$ or $8{\sim}12{\mu}m$), and of materializing a vision system, when general optics materials are used, they don't react to the light in the range of long-wavelength, and can't display their optic functions. Therefore, the materials with the feature of higher refractive index, reacting to the range of long-wavelength, are to be used. The kinds of materials with the characteristic of higher refractive index are limited, and their features are close to those of metals. Because of these metallic features, the existing producing method of optical systems were direct manufacturing method using grinding method or CAD/CAM, which put limit on productivity and made it difficult to properly cope with the increasing demand of markets. GASIR, a material, which can be molded easily, was selected among infrared ray optics materials in this study, and the optical system was designed with two Aspheric lenses. Because the lenses are molded in the environment of high temperature and high pressure, they require a special metallic pattern. The metallic pattern was produced with materials with ultra hardness that can stand high temperature and high pressure. As for the lens mold, GMP(Glass Molding Press) of the linear transfer method was used in order to improve the productivity of optical systems for thermal infrared cameras, which was the goal of this paper.

• 한국인터넷방송통신학회논문지
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• 제20권3호
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• pp.15-23
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• 2020

IoT 산업이 확대되면서 기기들의 위치정보를 측정하고 활용하는 다양한 응용서비스들이 많이 출시되고 있다. 이러한 위치정보를 전송하기 위해 Bluetooth, Wi-Fi, Zigbee 등 여러 무선통신 기술들이 사용된다. 하지만 이 기술들은 제한된 커버리지를 가지고 있으며, 비교적 넓은 커버리지를 갖는 셀룰라 망은 이용비용을 지불해야하는 단점을 가지고 있다. 본 논문에서는 저전력 장거리 무선 통신 기술인 LoRa(Long Range)를 이용하여 자체적인 위치정보시스템을 구현하였다. 이 구현 시스템은 LoRa 기술을 활용하기 때문에 다른 무선통신 기술보다 비교적 넓은 커버리지를 가질 뿐만아니라 이용비용이 발생하지 않는다. 또한 위치정보시스템은 CoAP와 6LoWPAN을 사용하여 IPv6 형태로 패킷을 전송하기 때문에 기존 인터넷 환경에서 다수의 기기들과 연동이 가능하다.

• 한방비만학회지
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• 제22권1호
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• pp.77-85
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• 2022

While the Coronavirus disease 2019 (COVID-19) pandemic is gradually turning into an endemic disease, concerns about post COVID-19 conditions (Long COVID) are emerging. Obesity is a major risk factor for severe complications of COVID-19, and COVID-19 has a wide range of effects on obesity and metabolic function. This paper aims to examine the interaction between COVID-19 and obesity, the effects and mechanisms of long COVID on obesity, and the role of Korean medicine on long COVID-related obesity. Obesity may worsen with cardiometabolic damage and psychosocial insecurity during COVID-19 and long COVID-induced neuroinflammation, systemic inflammation, mitochondrial dysfunction, and hypoxia also may aggravate obesity. Korean Medicine treatments, which have been widely used to treat obesity, have the potential to improve obesity in the era of long COVID by intervening in these mechanisms.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 1999년도 춘계학술대회 논문집
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• pp.125-127
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• 1999

• 한국광학회:학술대회논문집
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• 한국광학회 2008년도 하계학술발표회 논문집
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• pp.419-420
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• 2008