• Journal of Korean Tunnelling and Underground Space Association
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• v.16 no.3
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• pp.269-285
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• 2014

In spite of the importance of the natural ventilation pressure(NVP) in tunnels for the optimal design of the ventilation system, there have been only few studies on the NVP because its measurement and quantitative analysis are not straightforward. This study aims at quantifying the amount of the NVP with the terrain and meteorological data for the local major tunnels. And ultimately this will lead to developing the guidelines for quantifying and applying NVP for the optimal design of tunnel ventilation system. 22 local tunnels in the major routes are studied for the NVP quantification. NVP derived from the meteorological data is in the range of 20~140 Pa, while NVP estimated from the terrain data ranges from 20 to 200 Pa. Since the jet fan pressure is about 10~15 Pa per unit, the minimum level of NVP expected in the local tunnels is larger than the pressure rise by one unit of the ordinary jet fan. This implies that NVP in local tunnels should be quantified and be taken into consideration for the economic and safe ventilation design. The barometric pressure difference between tunnel portals is found to be the most influential factor, accounting for 61% of the NVP, while the wind pressure acting on the portals and the chimney effects occupy 22% and 17%, respectively.

• Journal of the Korean Geotechnical Society
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• v.27 no.10
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• pp.25-33
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• 2011

Suction buckets have been widely used for offshore structures such as anchors for floating facilities, and the foundations of offshore wind energy turbines. However, the design guidelines for suction buckets have not been clearly suggested. Therefore, this study performed the numerical analysis by using ABAQUS (2010) to evaluate bearing capacities and load-movement behaviors of the suction bucket in NC clay. For the numerical analysis, the depth ratio L/D (L=embedded length of skirt; D=diameter of a bucket) was varied from 0.25 to 1.0. The analysis results showed that the L/D ratio has a significant effect on the bearing capacity, and the vertical and horizontal capacities respectively increased by about 40% and 90%, when L/D ratio increased from 0.25 to 1.0. At the vertical loading, the bucket showed the similar failure mode with a deep foundation, so the shaft and toe resistances can be separately evaluated. At the horizontal loading, the bucket with L/D=O.25 showed the sliding failure mode and the bucket with $L/D{\geq}0.5$ showed the rotational failure mode.

• Journal of the Korean Geographical Society
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• v.43 no.6
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• pp.824-842
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• 2008

The main objective of the study was to analyze the weather conditions of frost occurrence for protecting crops against frost damage in Korea. The primary data used for the analysis of meteorological characteristics of frost occurrence days are the airmass pattern, minimum temperature, grass minimum temperature, daily temperature range, relative humidity, minimum relative humidity, mean wind speed in autumn and spring. Frost often occurs when the migratory anticyclone passes the southwest of Korea. The importance of grass minimum temperature measurements for agricultural purposes has previously been recognized. The grass minimum thermometer is capable of detecting ground frosts which are often not recorded by the minimum thermometer. The minimum temperature of frost occurrence days is above $0^{\circ}C$ in the coastal area, but the grass minimum temperature of frost occurrence days is below $0^{\circ}C$ in the whole area. The daily temperature of frost occurrence days is about 9 to $12^{\circ}C$ in the coastal area and is over $14^{\circ}C$ in the inland area. The minimum relative humidity of frost occurrence days is about 30 to 50%. The mean wind speed of frost occurrence days is less than 2m/sec.

• Journal of the Korean earth science society
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• v.35 no.1
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• pp.41-53
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• 2014

The special observation using Radiosonde was performed to investigate precipitation events over the east coast of Korea during the winter season from 5 January to 29 February 2012. This analysis focused on the various indices to describe the characteristics of the atmospheric instability. Equivalent Potential Temperature (EPT) from surface (1000 hPa) to middle level (near 750 hPa) was increased when the precipitation occurred and these levels (1000~750 hPa) had moisture enough to cause the instability of atmosphere. The temporal evolution of Convective Available Potential Energy (CAPE) appeared to be enhanced when the precipitation fell. Similar behavior was also observed for the temporal evolution of Storm Relative Helicity (SRH), indicating that it had a higher value during the precipitation events. To understand a detailed structure of atmospheric condition for the formation of precipitation, the surface remote sensing data and Automatic Weather System (AWS) data were analyzed. We calculated the Total Precipitable Water FLUX (TPWFLUX) using TPW and wind vector. TPWFLUX and precipitation amount showed a statistically significant relationship in the north easterly winds. The result suggested that understanding of the dynamical processes such as wind direction be important to comprehend precipitation phenomenon in the east coast of Korea.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.141-142
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• 2007

In recent years, the rate of mean sea level rise is increasing rapidly from the phenomena of global warming, together with the increasing trend of the storm scale. The issue of sea level rise is multifaceted and produces a range of environmental problems. Especially, high tides and the tidal currents become higher, and wave base increases, so the energy received at the coastal boundary may increase. This brings that many coastal environments go into disequilibrium, such as damages to the structures, erosion, and deposition Similarly it was known that the problems of nearshore processes and damage of berth and counter facilities during storm period had appeared at the small fishery port. Here we try to analyze the impact of the rearrangement of counter facilities and berth layout adopted for tranquility of its'inner harbor. Because this harbor is being connected to channel and open sea, the rearrangement of the structures might affect to the current speed and direction and wave height, so do to the sea bottom undulation. Therefore, we made model test for the several layouts of the berth and breakwater in this area.

• Herbal Formula Science
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• v.22 no.1
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• pp.13-32
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• 2014

Objectives : Until now the study of Cnidii Rhizoma, hemorrhage, brain waves, such as ischemic brain injury, analgesic, effect overcome of the stress from pregnancy melanin formation and inhibiting effects skin whitening have been published regarding this article. Cnidii Rhizoma demonstrates its different abilities depending on the characteristics. This paper reported that effect of Cnidii Rhizoma in Dongeuibogam blended prescriptions as main medicine. In addition, by analyzing data, we studied about utilizing of Cnidii Rhizoma. Methods : Cnidii Rhizoma in Dongeuibogam Prescriptions as the main ingredient was built with database of 202 prescriptions. Thus analyzed data was summarized in detail.(Table-1) If there is no difference in the title of the prescription but in other case the configuration information is different, formulations 1 and 2 were divided by the table. Results : The following results were reached through investigations on the prescriptions usikng Cnidii Rhizoma as a key component. 1. Prescriptions taking Cnidii Rhizoma as a monarch drug are utilized for 40 therapeutic purposes. In particular, 12.3% of prescriptions appear in the chapter of head, and 10.8% of those appear in the chapter of women, and 9.4% of eye, 8.9% of child, 6.4% of wind disease respectively. 2. Prescriptions utilizing Cnidii Rhizoma as the main ingredient are used in the treatment of headache, dizziness and pregnancy hemorrhage fetal movement, premature birth and they are also used for treating 131 different types of disease. 3. The dosage of Cnidii Rhizoma in formulas is from 2pun(about 0.75g) to 5don(nearly 18.75g), however 1don(nearly 3.75g) has been taken the most for clinical application. 4. We find out that according to herbs or prescriptions, Cnidii Rhizoma has a variety of functions such as ascending & descending of energy. Samultang is the most useful base prescription which used the Cnidii Rhizoma as the main component. Conclusion : These results suggest that, Cnidii Rhizoma once-amount use (don nearly 3.75g) 4g in head, gynecology, ophthalmology, pediatrics and paralysis disease associated with oriental medicine resource development can be considered to be widely used These results suggest that Cnidii Rhizoma was used most with 1 don(4g) and can be widely used for the resource development to the disease such as brain, gynecology, ophthalmologhy, pediatrics and wind-associated symptoms.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.6
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• pp.59-64
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• 2010

Building a firebreak against surface forest fire is a typical indirect suppression method that stops spread of flame by removing surface fuel, such as fallen leaves and bushes. In the sense of fire dynamic, building a firebreak is to set a section which will block thermal energy from igniting on virgin fuel. This study suggests and evaluates a calculation method for width of firebreak against surface fire for variant wind and slope conditions by applying the Point Source Model (PSM) to fallen leaves of Pinus densiflora. Width of firebreak was measured based on the distance the threshold radiant heat igniting Pinus densiflora fallen leaves at the heat flux of $4.9\;kW/m^2$ reaches. As a result, at the wind velocity of 0~5 m/s and on the slope of $0{\sim}50^{\circ}$, the appropriate width of a firebreak was 0.35~0.65 m for the mean flame height and 0.75~1.05 m for the maximum flame height. Accordingly, considering the factor of safety, the most appropriate width of a firebreak is 1.05 m based on the maximum flame height. Additional comparative analyses through experiments and field surveys are deemed necessary to determine appropriate widths of firebreak for different types of surface fuel.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.2
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• pp.48-55
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• 2011

Solar radiation components reflected by the sea surface ($R_{ss}\uparrow$) are additional energy sources comprising the solar radiation regime. Previous studies, based on observational approaches, indicated that $R_{ss}\uparrow$ is an available climatological resource. However, an estimation process for $R_{ss}\uparrow$ has not been established. In this case study over Jeju Island in South Korea, we applied a new estimation process to solar radiation modeling and discussed the spatial distribution of $R_{ss}\uparrow$ and its seasonal variation. Our results showed that the illuminated area and the intensity of $R_{ss}\uparrow$ became greatest at the winter solstice and least at the summer solstice. We estimated the illuminated area of $R_{ss}\uparrow$ as it expanded over the southern slope of Jeju Island. At the winter solstice, on a daily basis, the area and intensity of illumination by $R_{ss}\uparrow$ were $182.3km^2$ and $0.41\;MJ\;m^{-2}\;day\;{-1}$, respectively. Comparing the daily accumulative and instantaneous values of $R_{ss}\uparrow$ intensity, the difference was about 20 times greater in daily cases than in instantaneous cases. On the other hand, for instantaneous values, the $R_{ss}\uparrow$ intensity accounted for up to 33% of the three components, i.e., direct, diffuse and reflected radiation in winter solstice. In addition, it was estimated that the sea surface reflectance depended on the wind speed. Therefore, in a practical use of this revised model, wind conditions should be considered as a critical factor in estimating $R_{ss}\uparrow$.

• Journal of the Korean Applied Science and Technology
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• v.29 no.2
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• pp.193-198
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• 2012

The following results are from the test of semi-gel electrolyte to store energy efficiently and use advanced VRLA batteries by photovoltaic and wind power generation. Semi-Gel electrolyte with Silica 5% became Gel after 1 and half hour. It shows it is the most suitable time that the electrolyte can be absorbed into the separator and active material of plate to be gel. The test also says that semi-gel electrolyte shows the much better performance for low-rate discharge and the liquid electrolyte is good for high-rate discharge because the reaction rate of gel electrolyte is slower than liquid one for high-rate discharge performance. The test with DOD10% and DOD100% says that 5% silica electrolyte shows much better performance for life efficiency than liquid one. Because semi-gel electrolyte increase the efficiency of gas recombination at the chemical reaction of VRLA battery and it makes minimizing the reduction of electrolyte. Using the 5% silica electrolyte in order to improve the stroage efficiency and life performance for photovoltic and wind power generation, it causes improving by 4.8% for DOD100% and 20% for DOD10%.

• Journal of Acupuncture Research
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• v.20 no.1
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• pp.131-143
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• 2003

Objective : The purpose of this study is to arrange the literature about acupuncture therapy on the hemorrhoids and hemorrhoid complicated by anal fistula. Methods : We arrange Huang Di Nei Jing and fifteen kinds of literature about the hemorrhoids and hemorrhoid complicated by anal fistula. Results : 1. The cause of hemorrhoids are overfatigue, overeating, imbalance of stool(const-ipation or diarrhea), uncontrol sexual excess or abstinence, pathgenic factors of wetness, heat, wind, dry, fire, chronical hemorrhoids that has not been treated, and general weakness. 2. Symptom of hemorrhoids is that skin is projected form the nine holes or varicose extension to become hemorrhoid. Hemorrhoids is small nodosity that projected on the anal inter or outer region, and hemorrhoid complicated by anal fistula is pus which comes out form one or some fistula on the anal around inter and outer region. 3. Therapy method of hemorrhoid and hemorrhoid complicated by anal fistula are elimination pathological heat from blood, promote blood flow to remove blood stasis, cold in nature and purge away fire, remove heat form the blood, promote blood flow to remove blood stasis, cold in nature and purge away fire, remove heat from the blood and eliminate dampness, tonify the spleen and replenish Ki, dispel wind and alleviate pain and so forth. Therapy method of hemorrhoid is to give the first consideration to relieve blood: eliminating pathological heat form blood complicated by anal fistula is to tonify the blood first, than after that eliminating pathological heat form blood. About external method are method of fumigation, method of ointment, method of close with medicine, necrotizing method and also operation(injection, bind etc.)was used for treatment. 4. The prescription are Gurgak-hwan, Wypi-hwan, Gunggyi-tang, Jingyochangchul-tang, Jingyobangpung-tang, Mokhyangbinrang-hwan, Ochi-san, Gamihyanso-san, Jojang-hwan, Sinyung-hwan used frequently. 5. food taboo on patient's diet of the hemorrhoid and hemorrhoid complicated by anal fistula are raw grain, cold or dampness food, alcohol, hot food, Singiberis rhizoma recens, Cinnamomi ramulus. 6. Acupuncture therapy on the hemorrhoid and hemorrhoid complicated by anal fistula are, in the first stage eliminating pathological heat form blood and eliminate dampness, and in the long term eliminate dampness, promote and remove meridian energy, remove that form the intestines, dispel channels and collaterals. 7. Acupuncture points at B2, CV1, B58, B36, B56, Sp5, S30, B25, B54, GV1, GV20, L6, B40 used frequently for the acupuncture therapy, and acupuncture point at GV4, GV1, B30, hemorrhoidal point used form moxibustion. Reduction blood at B40 and blue capillary of Sp9 and acupuncture Chungbaek, Ki-gack, Ki-jung, Ki-mun(Dongsh Kihyel) makes the treatment very effective.