• Atmosphere
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• v.28 no.2
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• pp.187-200
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• 2018

The heavy snowfall phenomenon with thunder and lightning occurred in Yeongdong coastal region on 20 January 2017. Amount of snow on that day was a maximum of 47 cm and was concentrated in a short time (2 hours) at the Yeongdong coastal area. The mechanism of thundersnow was investigated to describe in detail using observational data and numerical simulation (Weather Research and Forecast, WRF) applied lightning option. The results show that a convective cloud occurred at the Yeongdong coastal area. The east wind flow was generated and the pressure gradient force was maximized by the rapidly developed cyclone. The cold and dry air in the upper atmosphere has descended (so called tropopause folding) atmospheric lower layer at precipitation peak time (1200 LST). In addition, latent heat in the lower atmosphere layer and warm sea surface temperature caused thermal instability. The convective cloud caused by the strong thermal instability was developed up to 6 km at that time. And the backdoor cold front was determined by the change characteristics of meteorological elements and shear line in the east sea. Instability indexes such as Total totals Index (TT) and Lightning Potential Index (LPI) are also confirmed as one of good predictability indicates for the explosive precipitation of convective rainfall.

• Atmosphere
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• v.30 no.3
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• pp.257-276
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• 2020

Faithful evaluation of the meteorological input is a prerequisite for a better understanding of air quality model performance. Despite the importance, the preliminary meteorological assessment has rarely been concerned. In this study, we aim to evaluate the performance of the Weather Research and Forecasting (WRF) model conducting a year-long high-resolution meteorological simulation in 2016 over the Seoul metropolitan area. The WRF model was configured based on a series of sensitivity simulations of initial/boundary meteorological conditions, land use mapping data, reanalysis grid nudging method, domain nesting method, and urban canopy model. The simulated results of winds, air temperature, and specific humidity in the atmospheric boundary layer (ABL) were evaluated following statistical evaluation guidance using the surface and upper meteorological measurements. The statistical evaluation results are presented. The model performance was interpreted acceptable for air quality modeling within the statistical criteria of complex conditions, showing consistent overestimation in wind speeds. Further statistical analysis showed that the meteorological model biases were highly systematic with systematic bias fractions (f_SB) of 20~50%. This study suggests that both the momentum exchange process of the surface layer and the ABL entrainment process should be investigated for further improvement of the model performance.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.1 no.1
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• pp.19-30
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• 1968

An experiment on the culture of laver, Porphyra tenera, was carried out from September 26, 1965 to February 12, 1966 at a laver farm on the coast of Gae-do, Hwacheong-myeon, Yeocheon-gun, Jeonranam-do, using 'Sae-ol-bal' (triple-knotted blind) laver bed, resulting in the following data: 1. 'Sae-ol-bal' laver, bed was less destroyed compared to ordinary (dual knotted blind) laver bed, the destruction rate being $9.8\%$ in 'Sae-ol-bal' laver bed, while $35.3\%$ in ordinary laver bed (Table 5). 2. The quantity of laver yield is the greatest on the edge-part, the next on the basal part, and the smallest on the middle part of the 'Sae-ol-bal' laver bed (Table 6, Figs. $7\~8$). 3. The ordinary laver bed may yield better harvest on the calm farm but 'Sae-ol-bal' laver bed yields better harvest at a farm where the destruction of bed is remarkable by wind and wave action.

• The Journal of the Korea Contents Association
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• v.8 no.8
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• pp.90-102
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• 2008

One of the most distinctive characteristic of the animations of Miyazaki Hayao is appearance of heroines with firm beliefs as well as compassion and generosity.. This study aimed to conduct research into the common points and differences in personality structures targeting <Nausicca of the Valley of WInd>, <Laputa: the Castle in the Sky>, <Mononoke Hime>, and <The Spiriting Away of Sen and Chihiro>, in which heroines appear out of long animation films created and directed by Hayao, In order to analyze the personality types, the study applied the classification criteria of MBTI and enneargram, and it analyzed the personality structures in comprehensive consideration of organic relationships and external characteristics according to the roles of the characters. This study analyzes that their personality type could be created very indivisually by changing their behavior motives, though Miyazaki's heroines are both Savior and idealist. Also, the study defined the characteristics of the personality structures of heroines created by Miyazaki Hayao and prepared data about them based on the results.

• Atmosphere
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• v.21 no.1
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• pp.45-55
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• 2011

A definition on the tropical cyclone (TC) that influenced the Korean Peninsula (KP), the KP-influence TC, is widely used in the TC communities, but its criterion is not clear mainly due to the ambiguity and subjectiveness of the term such as 'influence', which led to the inconsistent TC statistical analysis. This study suggests a definition and criterion on the TC approaching to the KP (KP-approach TC) additionally, which is more obvious and objective than the KP-influence TC. In this study, the criterion on the KP-approach TC is determined when the TC's center from the RSMC best track data encounters the box areas of $28^{\circ}N{\sim}40^{\circ}N$ and $120^{\circ}E{\sim}138^{\circ}E$. The range is chosen by finding a minimum area that includes all official KP-influence TCs except three TCs that affected the KP as a tropical depression (TD). Statistical analysis reveals that, among total 1,537 TCs that occur in the western North Pacific during 1951-2008, the KP-approach TC was 472, the KP-influence TC was 187, and the KP-landfall TC was 87. August was the month that the largest TCs approach and influence to the KP. Finally, this paper suggests to determine the KP-influence TC by the strong wind and heavy rain advisories in the KP based on the observation after the storm's passage.

• Korean Journal of Remote Sensing
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• v.34 no.1
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• pp.25-43
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• 2018

The effects of hydro-meteorological and surface variables on the frequency of Asian dust events (FAE) were investigated using ground station and satellite-based data. Present weather codes 7, 8, and 9 derived from surface synoptic observations (SYNOP)were used for counting FAE. Surface wind speed (SWS), air temperature (Ta), relative humidity (RH), and precipitation were analyzed as hydro-meteorological variables for FAE. The Normalized Difference Vegetation Index (NDVI), land surface temperature (LST), and snow cover fraction (SCF) were used to consider the effects of surface variables on FAE. The relationships between FAE and hydro-meteorological variables were analyzed using Z-score and empirical orthogonal function (EOF) analysis. Although all variables expressed the change of FAE, the degrees of expression were different. SWS, LST, and Ta (indices applicable when Z-score was < 0) explained about 63.01, 58.00, and 56.17% of the FAE,respectively. For NDVI, precipitation, and RH, Asian dust events occurred with a frequency of about 55.38, 67.37, and 62.87% when the Z-scores were > 0. EOF analysis for the FAE showed the seasonal cycle, change pattern, and surface influences related to dryness condition for the FAE. The intensity of SWS was the main cause for change of FAE, but surface variables such as LST, SCF, and NDVI also were expressed because wet surface conditions suppress FAE. These results demonstrate that not only SWS and precipitation, but also surface variables, are important and useful precursors for monitoring Asian dust events.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.4
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• pp.47-56
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• 2005

In GPS/INS/barometer navigation system for UAV, vertical channel damping loop was introduced to suppress divergence of the vertical axis error of INS, which could be reduced to the level of accuracy of pressure altitude measured by a pitot-static tube. Because static pressure measured by the pitot-static tube depends on the speed and attitude of the vehicle, static pressure error models, based on aerodynamic data from wind tunnel test, CFD analysis, and flight test, were applied to reduce the error of pressure altitude. Through flight tests and sensitivity analyses, the error model using the ratio of differential pressure and static pressure turned out to be superior to the model using only differential pressure, especially in case of high altitude flight. Both models were proposed to compensate the effect of vehicle speed change and used differential and static pressure which could be obtained directly from the output of pressure transducer.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.30 no.3
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• pp.46-61
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• 2017

Objectives : Allergic contact dermatitis(ACD) is a type IV delayed hypersensitivity reaction that results from cumulative exposures and subsequent sensitization to an environmental chemical. Lonicerae Caulis(LC) can clear away heat and relieve toxin, disperse wind and heat, dredge the channel. The present study was designed to investigate the effects of LC on allergic contact dermatitis(ACD) induced by 2,4-dinitrochlorobenzene(DNCB) in mice. Methods : In this experiment, the effects of LC on changes in body weights, ear and dorsum skin thicknesses, ear weights, clinical aspects on the dorsum skin, histopathological changes, spleen/body ratio, cytokines were investigated. In addition, the effects on proliferations of splenocytes were also investigated in vitro and vivo study. Results : LC spread(SPR) group and LC spread and administered(SPR+ADM) group showed diminished ear thicknesses. In SPR+ADM group, ear weights were lowered significantly compared to contact dermatitis control(CTL) group. LC treatment diminished erythema, desquamation and keratosis which were induced by repeated painting of DNCB. In histopathological observation, spongiosis and edema were diminished in SPR and SPR+ADM group. In cytokines, SPR+ADM group were increased in IL-10, and SPR and SPR+ADM group were decreased in TNF-${\alpha}$ compared with control group. Conclusions : These data suggest that LC can decrease symptoms of ACD, then LC is useful to treat patient with ACD.

• Journal of Digital Contents Society
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• v.19 no.5
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• pp.1011-1019
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• 2018

Existing exploration robot is able to control its speed using technologies such as the remote control and deep learning. However its speed control method using weather information has not been proposed. To overcome the problem of conventional methods without using the weather information which is an useful ordinary life information, this paper proposes a new speed control method of exploration robot using weather information gathered from RSS service which is offered without cost by the Meteorological Agency. The exploration robot implemented in this paper is controled by the remote control through the TCP/IP communication and provides real-time real spot figure gathered from its camera sensor within the range of WiFi. Additionally, according to the weather information from URL of the Meteorological Agency, the implemented exploration robot autonomously controls it speed. The correct performance of the proposed method is verified by the experimental measurement data of its speed according to the precipitation probability and wind speed in this paper.

• Water for future
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• v.28 no.6
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• pp.183-191
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• 1995

Applying microwave, a velocity measurement system has been developed in order to measure the velocity of stream water surface. It's main purpose is the measurement for high velocity of flood water. It is under the developing stage of experimental measurement system. The microwave surface velocity meter uses Doppler effects of microwave. It consists of a radio frequency(RF) part and that of signal processing. Thr RF part has the function of microwave oscillation, reception of reflected wave, and determination of Doppler frequency, etc. Signal processing designates amplification, fast Fourier transform, etx. Various measuring experiments were performed at bridges and a spillway of Taechong re-regulation dam with the microwave velocity meter. Verification test was also made through water tank of ship model test at Research Institute of Ships and Ocean Engineering. It shows 4% error inherent in A/D converter and additional several percentage errors from measurement circumstance. The measuring ranges are from 0.5 to 3.5 m/s. The result shows good linear relationship between carriage velocity and measured velocity, thus proves usefulness as a measuring instrument for flood water velocity. The instrument requires overall re-engineering procedure and number of data should be accumulated and analyzed to treat wind effects and random fluctuations of water surface.