• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.1
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• pp.55-63
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• 2016

Temperature lapse rate within the planetary boundary layer shows a diurnal cycle with a substantial variation. The widely-used lapse rate value for the standard atmosphere may result in unaffordable errors if used in interpolating hourly temperature in complex terrain. We propose a simple method for estimating hourly lapse rate and evaluate whether this scheme is better than the conventional method using the standard lapse rate. A standard curve for lapse rate based on the diurnal course of temperature was drawn using upper air temperature for 1000hPa and 925hPa standard pressure levels. It was modulated by the hourly sky condition (amount of clouds). In order to test the reliability of this method, hourly lapse rates for the 500-600m layer over Daegwallyeong site were estimated by this method and compared with the measured values by an ultrasonic temperature profiler. Results showed the mean error $-0.0001^{\circ}C/m$ and the root mean square error $0.0024^{\circ}C/m$ for this vertical profile experiment. An additional experiment was carried out to test if this method is applicable for the mountain slope lapse rate. Hourly lapse rates for the 313-401m slope range in a complex watershed ('Hadong Watermark 2') were estimated by this method and compared with the observations. We found this method useful in describing diurnal cycle and variation of the mountain slope lapse rate over a complex terrain despite larger error compared with the vertical profile experiment.

• Journal of the Korean Solar Energy Society
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• v.35 no.2
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• pp.73-83
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• 2015

When it comes to these buildings for business use, cooling load during summertime was reported to have great importance which, as a result, impressively increased interest in Solar Heat Gain Coefficient (SHGC). Such SHGC is considered to be lowered with the help of colors and functions of glass itself, internal shading devices, insulation films and others but basically, these external shading devices for initial blocking that would not allow solar heat to come in from outside the buildings are determined to be most effective. Of many different external shading devices, this thesis conducted an analysis on Exterior Venetian Blind. As for vertical shading devices, previous researches already calculated SHGC conveniently using concepts of sky-opening ratios. However in terms of the Venetian Blind, such correlation is not possibly applied. In light of that, in order to extract a valid correlation, this study first introduced a concept called shape factor, which would use the breadth and a space of a shade, before carrying out the analysis. As a consequence, the concept helped this study to find a very similar correlation. Results of the analysis are summarized as follows. (1) Regarding SHGC depending on the surface reflectance of a shade, an average of 2% error is observed and yet, the figure can always be ignored when it comes to a simple calculation. (2) As for SHGC of each bearing, this study noticed deviations of 4% or less and in the end, it is confirmed that extraction can be achieved with no more than one correlation formula. (3) When only the shape factor and nothing else is used for finding a correlation formula, the formula with a deviation of approximately 5% or less is what one would expect. (4) Since the study observed slight differences in bearings depending on ranges of the shape factors, it needed to extract a weighted value of each bearing, and learned that the smaller the shape factor, the wider the range of a weighted value. The study now suggests that a follow-up research to extract a simple calculation formula by dealing with all these various inclined angles of shade, solar radiation conditions of each region (the ratio of diffuse radiation to direct radiation and others) as well as seasonal features should be carried out.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.283-294
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• 2021

Solar radiation is an important meteorological factor in the agricultural sector. The ground exposed to sunlight is highly influenced by the surrounding terrains especially in South Korea where the topology is complex. The solar radiation on an inclined surface is estimated using a solar irradiance correction factor for the slope of the terrain along with the solar radiation on a horizontal surface. However, such an estimation method assumes that there is no barrier in surroundings, which blocks sunlight from the sky. This would result in errors in estimation of solar radiation because the effect of shading caused by the surrounding terrain has not been taken into account sufficiently. In this study, the shading effect was simulated to obtain the brightness value (BV), which was used as a correction factor. The shaded relief images, which were generated using a 30m-resolution digital elevation model (DEM), were used to derive the BVs. These images were also prepared using the position of the sun and the relief of the terrain as inputs. The gridded data where the variation of direct solar radiation was quantified as brightness were obtained. The value of cells in the gridded data ranged from 0 (the darkest value) to 255 (the brightest value). The BV analysis was performed using meteorological observation data at 22 stations installed in study area. The observed insolation was compared with the BV of each point under clear and cloudless condition. It was found that brightness values were significantly correlated with the solar radiation, which confirmed that shading due to terrain could explain the variation in direct solar radiation. Further studies are needed to accurately estimate detailed solar radiation using shaded relief images and brightness values.

• Journal of Korean Historical Folklife
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• no.34
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• pp.253-281
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• 2010

This study has its purpose on figuring it out to the religious notion in Vietnam with the material of the divinity construction of Den Hang Pho in Sapa where is the northern region of Vietnam. To make this, the study divides the type of Vietnamese temples into four parts; Chua, Den, Dinh, and Mieu. Among them, the study pays attention to 'Den' because Vietnamese historical heroes are seated as divinity. This reason makes a reasonable case to this study to figure out a typically and generally religious faith. First of all, the study analyzes immaculate divinity, which generally consists of three and four layered system. The study confirms that the immaculate divinity started from the goddess and then extended to the concept to dominate the sky, the ground, the sea(river), and the mountain(forest). General Tran Hung Dao is the best historical hero in Vietnam and has been placed in temples called Den. The study exams the context that the divinity extended to the religious beliefs, for examples, the belief related in a childbirth by lots of narrations and ceremonies and the belief to treat a sickness, and also exams the context that the divinity placed in a divinity to make a symmetrical relation with immaculate faith. The study exams the divinity construction of Den Hang Pho as its authentic case. In this case, the study could verify a case emphasized by mountain Holy Mother among immaculate faiths. Especially, the study can confirm that General Tran Hung Dao was apotheosized as a concept to be symmetrized with immaculate divinity, and futhermore, a couple of snakes was emphasized by their positioning to every room. Tri-system lays stress on the aboriginality(locality) centered on minority races in the northern Vietnam, the national identity of Vietnam, and the ecological condition of rivers flowing the valley of high and steep peak. The confirmed facts could be said to a construction what the religious notion of tri-system makes. The study makes a conclusion that this kind of conversion-oriented religious notion naturally corresponded with region, nation, and ecologically environmental condition, and extended to the Vietnamese faith with polytheistic divinity.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.5
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• pp.65-73
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• 2015

The purpose of this study was to compare the Mean Radiant Temperature(MRT) under two landscaping shade membranes, white and black, with those of natural outdoor spaces at summer midday. An additional perforated black shading net was applied and compared for the consideration of the practical application. The average MRT at the height of 2.4m, 10cm below the membranes of black, white, and perforated black were $49.1^{\circ}C$, $41.6^{\circ}C$ and $36.8^{\circ}C$ respectively, while that of open sky was $41.8^{\circ}C$. This indicates that a closer position to the darker membrane caused a higher MRT. At the height of 1.1m and 1.7m, the difference of MRT between the black and the white membranes was slight, while the value of white was unexpectedly higher than the black. The MRT of black perforated net showed the lowest value at every height. The black membrane absorbed more solar radiation than the white, which caused the greater release of long wave radiation and higher temperature near the membrane itself. In spite of the higher albedo of the white membrane, the higher solar radiation transmittance rate of which seemed to cause the slightly higher MRT than the black at the hight of 1.1m and 1.7m. In summary, the performance of the black membrane was slightly better than the white in terms of the air conditioning of the human related space around the height of 1.1m and 1.7m, when the shading membranes were at 2.5m height.

• Journal of the Korean earth science society
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• v.27 no.4
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• pp.450-463
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• 2006

Seasonal threshold values for fog detection over the ten airport areas within the Korean Peninsula have been derived from the data of polar-orbit Aqua/Terra MODIS and geostationary GOES-9 during a two years. The values are obtained from reflectance at $0.65{\mu}m\;(R_{0.65})$ and the difference in brightness temperature between $3.7{\mu}m\;and\;11{\mu}m\;(T_{3.7-11})$. In order to examine the discrepancy between the threshold values of two kinds of satellites, the following four parameters have been analyzed under the condition of daytime/nighttime and fog/clear-sky, utilizing their simultaneous observations over the Seoul metropolitan area: brightness temperature at $3.7{\mu}m$, the temperature at $11{\mu}m,\;the\;T_{3.7-11}$ for day and night, and the $R_{0.65}$ for daytime. The parameters show significant correlations (r<0.5) in spatial distribution between the two kinds of satellites. The discrepancy between their infrared thresholds is mainly due to the disagreement in their spatial resolutions and spectral bands, particularly at $3.7{\mu}m$. Fog detection from GOES-9 over the nine airport areas except the Cheongju airport has revealed accuracy of 60% in the daytime and 70% in the nighttime, based on statistical verification. The accuracy decreases in foggy cases with twilight, precipitation, short persistence, or the higher cloud above fog. The sensitivity of radiance and reflectance with wavelength has been analyzed in numerical experiments with respect to various meteorological conditions to investigate optical characteristics of the three channels.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.1
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• pp.1-10
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• 2012

Digital Forecast of the Korea Meteorological Administration (KMA) represents 5 km gridded weather forecast over the Korean Peninsula and the surrounding oceanic regions in Korean territory. Digital Forecast provides 12 weather forecast elements such as three-hour interval temperature, sky condition, wind direction, wind speed, relative humidity, wave height, probability of precipitation, 12 hour accumulated rain and snow, as well as daily minimum and maximum temperatures. These forecast elements are updated every three-hour for the next 48 hours regularly. The objective of this study was to construct Forest Fire Danger Rating Systems on the Korean Peninsula (FFDRS_KORP) based on the daily weather index (DWI) and to improve the accuracy using the digital forecast data. We produced the thematic maps of temperature, humidity, and wind speed over the Korean Peninsula to analyze DWI. To calculate DWI of the Korean Peninsula it was applied forest fire occurrence probability model by logistic regression analysis, i.e. $[1+{\exp}\{-(2.494+(0.004{\times}T_{max})-(0.008{\times}EF))\}]^{-1}$. The result of verification test among the real-time observatory data, digital forecast and RDAPS data showed that predicting values of the digital forecast advanced more than those of RDAPS data. The results of the comparison with the average forest fire danger rating index (sampled at 233 administrative districts) and those with the digital weather showed higher relative accuracy than those with the RDAPS data. The coefficient of determination of forest fire danger rating was shown as $R^2$=0.854. There was a difference of 0.5 between the national mean fire danger rating index (70) with the application of the real-time observatory data and that with the digital forecast (70.5).

• Journal of the Korean Society of Costume
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• v.20
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• pp.31-47
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• 1993

1. The relationship between Korea and Buk-Song had maintained for 164 years(964 1126 A.D). The period of relationship was from KwangJong Year 13(4years after establishing Buk-Song), Song Tae-Cho 1 year, to HeumJong Cheong Dang 1st year(InJong 4years in Koran). Author divides into three periodic terms, and remarkable diplomatic facts are as follows. 1) KwangJong year 13(963 A.D) SungJong year 13(994 A.D) : Normal relations, Song needed Korea's armed support. 2) MokJong year 6(1003 A.D) HyunJong year 9(1018 A.D) : Not steady relations and broke up, by MunJong year 26, Dang requested to resume the diplomatic relations. 3) MunJong year 25(1017 A.D) InJong 4(1126 A.D) : Song utilized Korea as a back supporter, but Song destructed by Keum. 2. Korea was donated knightage without offcial clothing by BukSong 10 times(KwangJong year 13 SungJong year 11). However during 164 years. Song presented some clothings Korea friendly. 3. Even though Korea cound not continue the steady diplomatic relations, Korea had been influenced the social systems including cloth-ing systems by Dang. Song dynasty. 4. The author studys historical materials which show that TongilSh-Shinra adapted social systems of Dang dynasty including clothing systems, which was succeeded to Korea for 200 years. Details are as follows ; 1) Original clothing color-systems which were Ja(purpil), Cheong(blue), Hwang(yellow), Pi, called 4-clored-system, of Tongil-Shinra, was suceeded to Korea, Above mentioned clothing systems of three countries of Korean peninsula. 2) When Korea unified the certificate of Pisam holders were superior from those of Tongil-Shinra and Hoo-Bakjae. There two classes used same seried-color 'ja, (Dan, Pi), Cheong(blue), Hwang(yellow)', or 'ja, (Dan, Pi), Cheong' and lasted to KwangJong year10 as a of-ficial clothing. 3) KwangJong year 7, according to the three colored official clothing system of Hooju, accepted Hooju's KwangJong year 11, that shifted 'Ja, (Dan, Pi), Cheong, Hwang', or, Ja, (Dan, Pi) Cheong', to 'Ja, Dan, Pi, Rok(green)'. 4) The clothing systems which are ja, (Dan, Pi), Rok which established KwangJong year 11 shifted to Song's, Ja, Ju(orange), Rok, Cheong, which had happened SungJong year 14 to MokJong 1st year. 5) 4-colored systems ('Ja, Pi, Rok, Cheong (distictable : sky blue, ocean blue)' shifted to 3 colored system which established Song ShingJong 1st year, which succeeded to Nam-Song and Keum. 5. The relationship between Korea and Yo had maintained for 207 years(918 1125 A.D). The period of relationship was from TaeJo 1st year to InJong year 3. 6. Yo, and Korea were called for king(15 times), prince(7 times). 7. Korea was donated knightage by Yo. The time when HyunJong year 13, Yo donated official clothing. From that time had used to do. The author divides into three periodic terms and discrives the shifting the formal clothing systems. Details were as follows ; 1) HyunJong year 13 MunJong year 8 : Even donating clothing systems from Yo had maintained for 35 years, Yeo, Song, Yo, three countries had not have formal cloth-ing, because they had been on the strug-gling. So that Korea had followed the same way of informal clothing. 2) MunJong year 918 : Yo donated the formal clothing to Korea for the King. Diplomatic condition was in the control, so that whole three countries used formal clothing. 3) MunJong year 19 YeaJong year 3 : Korea was donated 'Kuryumyun Kujangbokje', which became the formal clothings vs China.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.1
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• pp.29-33
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• 2011

Background and Purpose: Uniformity is the one of the important quality control features with respect to gamma cameras. To maintain adequate uniformity, we must acquire suitable flood table (=flood map) data because the flood table effects energy, and the type or dose of input radiation. Therefore, in this study we evaluated the difference in uniformity when uniformity does not match between the type of input radiation and the flood table data or collimator type. Subjects and Methods: For input radiation, we prepared 370 MBq of $^{57}Co$, $^{99m}Tc$, and $^{201}Tl$. Using SKYLight (Philips) and Infinia gamma cameras (GE), we acquired nine uniformity data that were corrected by technetium, cobalt flood table and did not corrected image for the three sources. Additionally, we acquired two uniformity images with a collimator that were corrected by intrinsic and extrinsic flood tables. Using this data, we evaluated and compared the uniformity values. Results: In the case of the SKYLight gamma camera, the uniformities of the images that matched between the input radiation and flood table with respect to $^{99m}Tc$ and $^{57}Co$ were better than the unmatched uniformity (3.96% vs. 5.69% ; 4.9% vs. 5.91%). However, because there was no thallium flood table, the uniformities of images at Tl were significantly incorrect (7.49%, 7.03%). The uniformities of the Infinia gamma camera had the same pattern as the SKYLight gamma camera (3.7% vs. 4.5%). Moreover, the uniformity of the $^{99m}Tc$ image acquired with a collimator and corrected by an extrinsic flood table was better than the intrinsic flood table (3.96% vs. 6.28%). Conclusion: Correcting an image by a suitable flood table can help achieve better uniformity for a gamma camera. Therefore, we have to acquire images with suitable uniformity correction, and update the flood table periodically. Whenever we acquire a nuclear medicine image, we always have to check the appropriate flood table according to the acquired condition.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.4
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• pp.76-84
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• 2010

Darangyi paddy in Namhae Gachon village provides natural beauty with its distinct location. Darangyi is a traditional Korean landscape, shaping a circular form to serve continuous cultivation. Despite the paddy's landscape, it is difficult to preserve its natural scenery due to many factors such as inadequate visual analysis. Under the belief that there is a necessity to preserve Darangyi paddy, the research in visual features of the paddy began to illustrate the relevance between its viewpoint and landscape objects. First, we researched typical view structures. When considering the visual features, Darangyi paddy landscape objects has a viewpoint from the horizontality to its below, which its center area is about $-5^{\circ}{\sim}-30^{\circ}$. From the analyzed data, the scenary of Darangyi paddy, which most people agree its decency, is formed in a visually decent location. The above type of measure of visual structure in Darangyi paddy is expected to be applied in maintenance of foothold of views in the future. Second, the surrounding elements play important parts to form the whole landscape of Gachon Darangyi paddy. Although Darangyi paddy is the principal part of the scenary, the landscape analysis showed a high relevance with the paddy's identity, forest around the paddy, sky, ocean, settlements, and the roads in terms of visual perception. It was affirmed that those elements around the paddy play important parts in structuring and providing the beauty of the whole landscape. Various viewy objects are seen obvious especially in a long distance, and the splendid scenary proved that those viewy objects are in indispensable location. In order to preserve the paddy, it seems necessary to consider the surrounding envrionment of Darangyi paddy, not just the paddy's sole landscape form. Third, Darangyi paddy has a distinct seasonal characteristics. According to the survey analysis, the full heading time in spring and time when people can take a picture against the sun light proved magnificence of Darangyi paddy. Thus, it would be ideal to maintain Darangyi paddy by securing the sunlight condition with decent landscape view and the views from its surrounding environments or researching the ways to principally maintain the surrounding environments.