• 신재생에너지
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• 제10권2호
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• pp.29-39
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• 2014

This study examines the future variability of surface wind speed and solar radiation based on climate change scenario over the Korean Peninsula. Climate change scenarios used in this study are RCP 4.5 and 8.5 with a 12.5 km horizontal resolution. Climate change scenario RCP 4.5 and 8.5 reproduce the general features of wind speed over the Korean Peninsula, such as strong wind speed during spring and winter and weak wind speed during summer. When compared with the values of wind speed and solar radiation of the future, they are expected to decrease current wind and solar resource map. Comparing the resource maps using RCP 4.5 and 8.5 scenarios, wind speed and solar radiation decrease with increasing greenhouse gas concentration. Meteorological resource maps of future wind and solar radiation should be improved with high resolution for the industrial application.

• 한국의학물리학회지:의학물리
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• 제26권3호
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• pp.185-191
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• 2015

방사선치료는 수술, 항암치료와 함께 암의 3대 치료방법으로 많은 암환자들이 방사선치료를 받게 된다. 방사선은 눈에 보이지 않아 방사선 치료기계에서 나가는 방사선의 질과 양을 확인하기 쉽지 않고 산란되는 특성 때문에 다른 장기에 2차암이 유도할 수 있고 최근 치료기술의 발달로 치료 방사선에 대한 보다 정밀한 검증이 필요하게 되었다. 따라서 방사선 치료기기에 대한 품질관리를 철저히 해야만 한다. 국제원자력기구, 미국의학물리학회 등 해외에서는 보고서들을 제시하여 각 지역적인 차원에서 방사선 치료기기의 품질관리에 대한 권고를 제시한다. 하지만 국내는 외국에 비해 규모가 작아 각 병원에서 국외의 권고 중 일부를 선택적으로 사용한다. 국내 병원을 대상으로만 한 방사선치료의 품질관리 권고가 존재하지 않지만 국외의 권고들이 갱신되고 있으며 향후 국내 품질관리 권고를 제작하기 위해 국내 품질관리의 현황 역시 조사 및 갱신 될 필요성이 있으므로 본 연구에서는 방사선치료기에 대한 품질관리 설문지를 제작하여 국내 품질관리 경향에 대한 조사를 실시하였다. 초본으로 제작된 설문지를 국내 5개 기관의 의학물리학자에게 배포하여 설문지의 부족한 점을 파악하고 보충하여 최종 설문지를 제작한 후 이를 전국 72개 병원의 방사선 종양학과에 배포하여 조사를 실시하였다. 72개 병원 중 37개 병원에서 요청에 응답해주었으며 이들 중 97.3%의 병원이 선형가속기를 보유하고 있으며 40.54%, 18.92%, 24.32%의 병원이 각각 근접치료장치, 토모치료장치, 방사선수술장치를 보유하고 있는 것으로 나타났다. 이 밖에 품질관리 인력 및 장치, 국내의 환자 품질관리 현황, 각 치료기별 품질관리 현황에 대한 설문이 실시되었으며 이 결과는 향후 표준 품질관리 절차서가 제작될 경우 사용되기에 좋은 자료가 될 것이다.

• 태양에너지
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• 제11권3호
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• pp.3-8
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• 1991

우리나라의 오지 또는 섬 등지에 태양에너지 이용기기의 설치는 대체에너지 이용차원에서도 실현되어야 할 분야이다. 이러한 태양에너지 이용기기의 설계를 위한 필수자료는 신뢰성있는 일사량의 측정 및 그의 분석이다. 그러나 국내에는 15개 지역에 일사량을 측정할 수 있는 시스템이 설치되어 있지만 전력수급이 쉽지 않은 오지에서의 정확한 일사자원의 평가는 불가능하다. 따라서 본 연구를 통하여 무인자동일사량 측정시스템(KIER 시스템)을 개발하여 기존의 HWS 시스템과 같이 우리나라의 독도에 설치하여 그 성능을 비교하였다. 그 결과 절대오차가 3% 내외로 신뢰도가 높았으며, 1989년 10월부터 8개월 동안의 전 일사량의 평균치는 약 $2,330W/m^2$ day로 독도에서 태양에너지 이용시스템의 설치 및 활용가능성이 높은 것을 알 수 있었다. 본 KIER 시스템은 앞으로 독도 이외의 오지지역에도 설치를 추진할 예정이다.

• 전자공학회논문지A
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• 제32A권9호
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• pp.106-113
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• 1995

The radiation characteristics of the subreflector of a shaped dual offset reflector antenna are analyzed by the uniform theory of diffraction(UTD). The discrete shaped subreflector profile is transformed into an analytic function by the global interpolation. To obtain the first and the second derivative terms on the surface, the local interpolation method is used. The reflection point needed for the geometrical optics(GO) is found by using the multi-dimensional function minimizing algorithm. The radiation pattern of a Gregorian type shaped subreflector is presented. The characteristics of the radiation patterns for various feed edge taperings and frequencies are examined.

• 한국농림기상학회지
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• 제11권3호
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• pp.123-125
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• 2009

I thank Kang and Kim (this issue) for their interests and constructive comments on Kwon (2009) in which the objectives were to find the site-specific relationship between net radiation ($R_N$) and solar radiation ($R_S$) in major plant functional types in Korea and to examine its applicability for estimating $R_N$. The authors addressed six major points requesting clarification and suggesting improvement. Below, my replies are provided.

• Journal of Photoscience
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• 제9권2호
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• pp.400-402
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• 2002

We collected seeds of Solidago virgaurea plants growing at different altitudes on the Mt Hakusan area in Japan and cultivated them in a naturally-lit green house. Three-week-old seedlings were irradiated with supplemental UV-B for 12 h each day for 1 and 2 weeks. After a week of itradiation the seedlings of the population collected from the higher altitude at Oh-nanjiho (ON) had accumulated more anthocyanins than those from the lower altitude at Bettoh-deai (BD). Levels of anthocyanins in the ON seedlings were highly correlated with the dose of UV-B radiation and the correlation was also observed after 2 weeks. The growth of the third leaves was retarded by UV-B radiation in both populations. The extent of growth retardation in the third leaves was correlated with the dose of UV -B radiation in both populations. However, no significant difference in the extent of leaf area growth was observed between the ON and BD populations. The increase in plant fresh weight was extensively inhibited in the ON seedlings after 1 week of UV-B radiation. The inhibition was recovered to those in the BD population by 2 weeks irradiation. These results indicate that these populations respond differentially to supplementary UV -B radiation during the first week. Because flavonoids such as anthocyanins play an important role in protection against UV-B radiation in many plants, populations growing at higher altitude may be better able to adapt to increased global levels of UV-B radiation.

• 한국산업융합학회 논문집
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• 제4권3호
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• pp.319-327
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• 2001

The objective of this study is to clarify the effect of thermal radiation environments on human thermal comfort, depending on different canyon types and surface materials on the human thermal comfort in a housing complex in Pohang city, Korea. For this purpose, the operative temperature and new effective temperature were calculated based on the modified mean radiant temperature of canyon models variated by the existence of direct radiation existence, surface materials, and the width and length of the street spaces in a housing complex. These indices for the canyon have been calculated from the meteorological data of Pohang city, which include air temperature, relative humidity, air velocity, global solar radiation and cloud. And the monthly averages of these climate factors measured at noon have been used. The results are as follows: (1) It is revealed that the short-wave radiosity reached the human body is affected by direct solar radiation and surface materials, and the long-wave radiosity by canyon types. (2) The existence of direct solar radiation, the kinds of surface materials and canyon types affect operative temperature($OT_n$) and new effective temperature($ET^*{_n}$). (3) The analysis of the human heat balance in the canyon indicates that the influence of radiation on human body is marc likely to be affected by the existence of direct solar radiation on human model.

• Animal Systematics, Evolution and Diversity
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• 제30권1호
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• pp.39-43
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• 2014

In this brief report, alternative time-varying diversification rate models were fitted onto the phylogeny of global amphibians by considering one-constant-rate (OCR), one-continuous-shift (OCS) and multiple-discrete- shifts (MDS) situations. The OCS diversification model was rejected by ${\gamma}$ statistic (${\gamma}=-5.556$, p<0.001), implying the existence of shifting diversification rates for global amphibian phylogeny. Through model selection, MDS diversification model outperformed OCS and OCR models using "laser" package under R environment. Moreover, MDS models, implemented using another R package "MEDUSA", indicated that there were sixteen shifts over the internal nodes for amphibian phylogeny. Conclusively, both OCS and MDS models are recommended to compare so as to better quantify rate-shifting trends of species diversification. MDS diversification models should be preferential for large phylogenies using "MEDUSA" package in which any arbitrary numbers of shifts are allowed to model.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 춘계학술대회논문집
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• pp.688-691
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• 2004

We have studied the possibility of global noise reduction by the sound power control through selection of distribution and impedance of absorptive materials. It is necessary to investigate the relation between the global sound energy in the field and the total sound power radiated by sources. In the previous work (1,2), the authors presented a useful design method to change boundary condition that can be useful to reduce noise in acoustically small enclosures. The possibility of total acoustic potential energy reduction by acoustic source power control is examined in an acoustically small cavity. Using acoustic energy balance equation, the relation between global noise control performance and absorptive material's arrangement/impedance is deduced. Numerical simulation is performed to interpret its physical meaning in terms of absorbent's distribution and impedance.

• International Journal of Oral Biology
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• 제47권2호
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• pp.17-24
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• 2022

Preserving intact genetic material and delivering it to the next generation are the most significant tasks of living organisms. The integrity of DNA sequences is under constant threat from endogenous and exogenous factors. The accumulation of damaged or incompletely-repaired DNA can cause serious problems in cells, including cell death or cancer development. Various DNA damage detection systems and repair mechanisms have evolved at the cellular level. Although the mechanisms of these responses have been extensively studied, the global RNA expression profiles associated with genomic instability are not well-known. To detect global gene expression changes under different DNA damage and hypoxic conditions, we performed RNA-seq after treating human cervical cancer cells with ionizing radiation (IR), hydroxyurea, mitomycin C (MMC), or 1% O₂ (hypoxia). Results showed that the expression of 184-1037 genes was altered by each stimulus. We found that the expression of 51 genes changed under IR, MMC, and hypoxia. These findings revealed damage-specific genes that varied differently according to each stimulus and common genes that are universally altered in genetic instability.