• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2009년도 한국우주과학회보 제18권1호
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• pp.30.3-30.3
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• 2009

• Journal of Biosystems Engineering
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• 제13권2호
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• pp.46-50
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• 1988

The estimation of beam radiation intensity on a tilted surface is very important to the design of a solar energy system. In order to get the beam radiation intensity, it is required to calculate the ratio of the diffuse solar radiation to the global radiation ($k_d$). The data measured at Chung-Buk National University. Cheong-ju, (from May 16, 1985 to Nov, 10, 1987) were analysed to define the relationship between hourly clearness index ($k_t$) and diffuse ratio ($t_d$). The results are is follow: 1. The percent of clearness index($k_t$) of less than 0.3 and of more than 0.8 were 2.7% and 3.1% respectively, and between 0.5 and 0.8 was 76.5%. 2. The regression equation between $k_t$ and $k_d$ was an exponential function as: $$k_d=\[{1\hspace{120}:\hspace{10}(k_t<0.1)\\1.28{\times}0.074^{k_t}\hspace{30}:\hspace{10}(0.1{\leq}=k_t<0.9)\\0.12\hspace{98}:\hspace{10}(0.9{\leq}=k_t)$$ There was a little difference between the result. of this study based on the data of 30 months and the results of previous study (ITRA 2(1):42-47, 1986.) based on the data of 8 months. 3. The hourly exponential regression equation between $k_t$ and $k_d$ was $k_d=A{\times}8^{k_t}$ and the values of constant A and coefficient B of the: equations are as the following table; 4. The percent of $k_d$ of less than 0.4 was 72.9% and of more than 0.7 was 6.6%. 5. Total mean value of $k_t$ and $k_d$ wert 0.56 and 0.32, respectively. From 10:00 to 15:00 o'clock the total mean value of $k_t$ was smaller that the hourly man value of $k_t$ and the one or $k_d$ larger.

• Radiation Oncology Journal
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• 제24권3호
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• pp.201-206
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• 2006

색소 융모 결절성 활액막염(pigmented villonodular synovitis, PVNS)은 병인이 밝혀지지 않은 증식성 질환으로, 병변의 범위에 따라 국소형과 미만형으로 분류되며, 조직학적으로 양성이지만 파괴적인 성향을 보이므로 연골의 파괴나 주위 조직으로 광범위한 침윤이 가능한 질환이다. 활액막 절제술이 일차적인 치료방법이지만 미만형인 경우에는 주위 조직을 침윤하는 성향 때문에 재발률이 높다. 재발이 반복된 후에는 수술적 절제가 어려워져서 병변부위의 절단이 필요하게 되므로, 광범위한 병변인 경우, 수술이 용이하지 않은 경우, 또는 불완전 절제가 시행된 경우 등에서 방사선치료를 시행하여 재발을 방지할 수 있다고 보고되고 있다. 저자들은 무릎관절의 미만형 색소 융모 결절성 활액막염으로 관절경을 이용한 육안적 활액막 전 절제술 후 방사선치료를 시행한 2예를 경험하였기에 문헌고찰과 함께 보고하고자 한다.

• 설비공학논문집
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• 제17권7호
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• pp.659-668
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• 2005

The thermal performances of glass evacuated tube solar collectors are numerically investigated. Four different shapes of solar collectors are considered and the performances of these solar collectors are numerically investigated. Dealing with only collecting tube, the effects of not only the shape of the absorber tube but also the incidence angle of solar irradiation on the thermal performance of the collector are studied because the energy obtained by the absorber can be varied according to the incidence angle of solar radiation. However, the solar irradiation consists of the beam radiation as well as the diffuse radiation. Also, in actual system, the interference of solar irradiation and heat transfer interaction between the tubes should be considered. Therefore, this study considered these effects is carried out experimentally and numerically. The accuracy of the numerical model is verified by experiments. The result shows that the thermal performance of the absorber used a plate fin and U-tube is about $25\%$ better than those of the other models.

• 대한두경부종양학회지
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• 제15권1호
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• pp.22-28
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• 1999

Purpose: We performed this study retrospectively to evaluate local control, survival, prognostic factors, and failure patterns in patients with non-Hodgkin's lymphoma of Waldeyer's ring. Materials and Methods: From April 1984 to November 1996,41 patients with non-Hodgkin's lymphoma of Waldeyer's ring were treated with combined chemotherapy and radiation therapy. Age was ranged from 19 to 73 years old with a median age of 55 years, and there were 26 male and 15 female patients. Primary site was tonsil in 26 and base of the tongue in 7 and nasopharynx in 8, and stage distribution showed stage I in 12 and stage II in 29 patients. Pathologic classification was done according to Working Formulation. There were 1 with follicular mixed small cleaved and large cell, 8 with diffuse small cleaved cell, 7 with diffuse mixed small and large cell, and 25 cases with diffuse large cell. All patients were treated with combination of chemotherapy and radiation therapy. Chemotherapy regimen consisted of either CHOP-Bleo(cyclophosphamide, adriamycin, vincristine, prednisolone, bleomycin) or COP-BLAM III(cyclophosphamide, vincristine, prednisolone, bleomycin, adriamycin, procarbazine). Radiation dose ranged from 3600cGy to 6620cGy with a median dose of 5040cGy. Follow-up time was ranged from 15 months to 159 months(median 55 months). Results: The complete response was achieved in 98%(40/41) and partial response in 2%(1/41). The complete response rate were the followings: 66.7% for stage I and 51.7% for stage II after chemotherapy, 100% for stage I and 96.6% for stage II after overall treatment respectively. The overall survival rate and disease-tree survival rates at 5 years were 82.6% and 79.5%, respectively. Prognostic factors for overall survival were age(p=0.007), stage(p=0.03), nodal status(p=0.006) and radiation dose(p=0.003). The factors associated with disease-tree survival were stage(p=0.04), nodal status(p=0.004) and radiation dose(p=0.009). The failure patterns were analized in evaluable 35 patients with complete response. Locoregional failure was noted in 2 patients and distant metastasis in 5 patients. Conclusion: Our results suggest that combined modality therapy is the appropriate treatment for stage I-II intermediate grade non-hodgkin's lymphoma of the Waldeyer's ring. However, our material is small and the analysis is retrospective. Randomized prospective studies for combined therapy, radiation therapy alone and chemotherapy alone are needed.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2001년도 추계학술대회 논문집
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• pp.335-335
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• 2001

Direct-normal, total horizontal and diffuse horizontal irradiance data obtained from a multi-filter rotating shadowband radiometer over seven different wavelength bands (416nm, 151nm, 616nm, 675nm, 870nm and 940nm and the entire spectrum) has been analyzed at Kwangju, South Korea from June 1998 December 2000. The maximum hourly global radiation flux ranged from 0.44 MJ/$m^2$ to 2.68 MJ/$m^2$ at around 11:00-12:00 Hr local time while the maximum hourly diffuse radiation flux ranged from about 0.96 MJ/$m^2$ to 1.37 MJ/$m^2$. The maximum hourly direct irradiance ranged from 1.42 MJ/$m^2$ to 2.92 MJ/$m^2$ from June1998-2000. During the period under consideration, the average monthly global radiation recorded were 13.09 MJ/$m^2$/day, 10.58MJ/$m^2$/day and 9.78MJ/$m^2$/day for years 1998, 1999 and 2000 respectively, while the diffuse irradiance were 6.54 MJ/$m^2$/day, 5.33 MJ/$m^2$/day and 5.14 MJ/$m^2$/day for f998, 1999 and 2000 respectively. The direct irradiance values at the site were 11.63 MJ/$m^2$/day, 8.24MJ/$m^2$/day and 7.75 MJ/$m^2$/day for 1998, f999 and 2000 respectively. It was observed that each of the years has its own unique meteorological parameters that affect the quality and quantity of radiation received for each month. The annual average daily fractions of the diffuse to the global radiation (KD) were 0.51, 0.61 and 0.59 for years 1998, 1999 and 2000 respectively. Analysis indicated that the average daily KD ranged from 0.13 to a maximum value of 0.99 in May for irradiance measured at the broadband channel while the maximum and minimum KD value of 0.91 and 0.23 was recorded at wavelength band 870nm and 940nm in January and September respectively. The lowest average daily clearness index (Kt) value recorded was 0.03 in May (Spring) and the annual average daily clearness indexes are 0.45, 0.34 and 0.35 for years 1998, f999 and 2000 respectively. The frequency of clear days annually at Kwangju is 67.95%, 29.57% and 40.72% for years 1998, 1999 and 2000 respectively.

• 천문학회지
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• 제37권5호
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• pp.307-313
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• 2004

Clusters of galaxies are believed to constitute a population of astrophysical objects potentially able to emit electromagnetic radiation up to gamma-ray energies. Evidence of the existence of non-thermal radiation processes in galaxy clusters is indicated from observations of diffuse radio halos, hard X-ray and EUV excess emission. The presence of cosmic ray acceleration processes and its confinement on cosmological timescales nearly inevitably yields in predicting energetic gamma-ray emission, either directly deduceably from a cluster's multifreqency emission characteristics or indirectly during large-scale cosmological structure formation processes. This theoretical reasoning suggests several scenarios to actually detect galaxy clusters at gamma-ray wavelengths: Either resolved as individual sources of point-like or extended gamma-ray emission, by investigating spatial-statistical correlations with unidentified gamma-ray sources or, if unresolved, through their contribution to the extragalactic diffuse gamma-ray background. In the following I review the situation concerning the proposed relation between galaxy clusters and high-energy gamma-ray observations from an observational point-of-view.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1294-1299
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• 2004

Transient radiative heat transfer is analyzed in a one-dimensional slab using finite volume method (FVM). In this study, the step, $2^{nd}$ order upwind, and QUICK schemes are used for incident diffuse radiation and collimated beam, respectively. The results for diffuse radiation show that all schemes applied in this study give good agreements with available published results. In case of collimated beam, however, the results show deviations from the analytical solutions. To successfully describe the propagations of collimated beam, shock capturing schemes such as TVD scheme are need to be developed.

• 대한기계학회논문집B
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• 제30권3호
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• pp.201-207
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• 2006

Transient radiative heat transfer is analyzed in a one-dimensional slab using finite volume method (FVM). In this study, the step, $2^{nd}$ order upwind, and QUICK schemes are used for incident diffuse radiation and collimated beam, respectively. The results fer diffuse radiation show that all schemes applied in this study give good agreements with available published results. In case of collimated beam however, the results show deviations from the analytical solutions. To successfully describe the propagations of collimated beam shock capturing schemes such as TVD scheme are need to be developed.

• 천문학회보
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• 제14권
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• pp.12.1-12.1
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• 1989