• Journal of Environmental Science International
• /
• v.4 no.2
• /
• pp.121-139
• /
• 1995

Based on the Results of Marine Meteorological and Oceanographical Observations (1966 -1987), the phenomenon of chimney is found as a candidate for the formation of the Japan Sea Proper Water (JSPW). The chimney phenomenon occurs twelve times Inuring 1966∼ 1987. The water types in the chimney denoting the deep convection are similar to those of the JSPW 0∼ 1℃ in potential temperature, 34.0∼34.1 ‰ in salinity and 68∼80 cl/t in potential thermosteric anomaly from the sea surface to the deep layer. The static stabilities in the chimney stations are unstable or neutral. This indicates that the winter time convection occurs. The JSPW sunken from the surface layer of chimney in winter spreads out under the Tsushima Warm Current area, following the isosteric surface of about 76 cl/t in Potential thermosteric anomaly. The formation of the deep water of the JSPW is mainly affected by the cooling of the sea surface than the evaporation of winds because the temperature and the salinity on the isoteric surface of about 76 cl/t in potential thermosteric anomaly ate cold and low The phenomenon of chimney occurred in here and there of the area in the north of 40" 30'N, west of 138" E. This suggests that the deep water of the JSPW is formed not in a limited area but probably in the overall region of the northern open ocean.

• Journal of the Korean association of regional geographers
• /
• v.16 no.5
• /
• pp.590-609
• /
• 2010

The purpose of the study is to propose and evaluate Exploratory Spatial Data Analysis(ESDA) methods for examining age-specific population migration characteristics. First, population migration pyramid which is a pyramid-shaped graph designed with in-migration, out-migration, and net migration by age (or age group), was developed as a tool exploring age-specific migration propensities and structures. Second, various spatial statistics techniques based on local indicators of spatial association(LISA) such as Local Moran''s $I_i$, Getis-Ord ${G_i}^*$, and AMOEBA were suggested as ways to detect spatial dusters of age-specific net migration rate. These ESDA techniques were applied to age-specific population migration of Daegu Metropolitan City. Application results demonstrated that suggested ESDA methods can effectively detect new information and patterns such as contribution of age-specific migration propensities to population changes in a given region, relationship among different age groups, hot and cold spot of age-specific net migration rate, and similarity between age-specific spatial clusters.

• Nuclear Engineering and Technology
• /
• v.26 no.1
• /
• pp.63-77
• /
• 1994

The objective of this work is to investigate fluid mixing phenomena related to pressurized thermal shock(PTS) in a pressurized water reactor(PWR) vessel downcomer during transient cooldown with direct vessel injection(DVI) using test models. The test model designs were based on ABB Combustion Engineering(C-E) System 80＋ reactor geometry. A cold leg small break loss-of-coolant accident(LOCA) md a main steam line teak were selected as the potential PTS events for the C-E System 80＋. This work consist of two parts. The first part provides the visualization tests of the fluid mixing between DVI fluid and existing coolant in the downcomer region, and the second part is to compare the results of thermal mixing tests with DVI in the other test model. Row visualization tests with DVI have clarified the physical interaction between DVI fluid and primary coolant during transient cooldown. A significant temperature drop was observed in the downcomer during the tests of a small break LOCA Measured transient temperature profiles agree well with the predictions by the REMIX code for a small break LOCA and with the calculations by the COMMIX-1B code for a steam line break event.

• Atmosphere
• /
• v.21 no.4
• /
• pp.391-404
• /
• 2011

This study investigates the impact of cumulus parameterization scheme (CPS) with different horizontal grid sizes on the simulation of the local heavy rainfall case over the Korean Peninsula. The Weather Research and Forecasting (WRF)-based real-time forecast system of the Joint Center for High-impact Weather and Climate Research (JHWC) is used. Three CPSs are used for sensitivity experiments: the BMJ (Betts-Miller-Janjic), GD (Grell-Devenyi ensemble), and KF (Kain-Fritsch) CPSs. The heavy rainfall case selected in this study is characterized by low-level jet and low-level transport of warm and moist air. In 27-km simulations (DM1), simulated precipitation is overestimated in the experiment with BMJ scheme, and it is underestimated with GD scheme. The experiment with KF scheme shows well-developed precipitation cells in the southern and the central region of the Korean Peninsula, which are similar to the observations. All schemes show wet bias and cold bias in the lower troposphere. The simulated rainfall in 27-km horizontal resolution has influence on rainfall forecast in 9-km horizontal resolution, so the statements on 27-km horizontal resolution can be applied to 9-km horizontal resolution. In the sensitivity experiments of CPS for DM3 (3-km resolution), the experiment with BMJ scheme shows better heavy rainfall forecast than the other experiments. The experiments with CPS in 3-km horizontal resolution improve rainfall forecasts compared to the experiments without CPS, especially in rainfall distribution. The experiments with CPS show lower LCL(Lifted Condensation Level) than those without CPS at the maximum rainfall point, and weaker vertical velocity is simulated in the experiments with CPS compared to the experiments without CPS. It means that CPS suppresses convective instability and influences mainly convective rainfall. Consequently, heavy rainfall simulation with BMJ CPS is better than the other CPSs, and even in 3-km horizontal resolution, CPS should be applied to control convective instability. This conclusion can be generalized by conducting more experiments for a variety of cases over the Korean Peninsula.

• Atmosphere
• /
• v.17 no.1
• /
• pp.55-68
• /
• 2007

Future climate changes over East Asia are projected by anthropogenic forcing of greenhouse gases and aerosols using ECHO-G/S (ECHAM4/HOPE-G). Climate simulation in the 21st century is conducted with three standard SRES scenarios (A1B, B1, and A2) and the model performance is assessed by the 20th Century (20C3M) experiment. From the present climate simulation (20C3M), the model reproduced reliable climate state in the most fields, however, cold bias in temperature and dry bias of summer in precipitation occurred. The intercomparison among models using Taylor diagram indicates that ECHO-G/S exhibits smaller mean bias and higher pattern correlation than other nine AOGCMs. Based on SRES scenarios, East Asia will experience warmer and wetter climate in the coming 21st century. Changes of geographical patterns from the present to the future are considerably similar through all the scenarios except for the magnitude difference. The temperature in winter and precipitation in summer show remarkable increase. In spite of the large uncertainty in simulating precipitation by regional scale, we found that the summer (winter) precipitation at eastern coast (north of $40^{\circ}N$) of East Asia has significantly increased. In the 21st century, the warming over the continents of East Asia showed much more increase than that over the ocean. Hence, more enhanced (weakened) land-sea thermal contrast over East Asia in summer (winter) will cause strong (weak) monsoon. In summer, the low pressure located in East Asia becomes deeper and the moisture from the south or southeast is transported more into the land. These result in increasing precipitation amount over East Asia, especially at the coastal region. In winter, the increase (decrease) of precipitation is accompanied by strengthening (weakening) of baroclinicity over the land (sea) of East Asia.

• The Journal of Pediatrics of Korean Medicine
• /
• v.18 no.1
• /
• pp.105-129
• /
• 2004

Methods: It was studied on the 47 kinds of oriental medical literature for fecal blood. Results: Fecal blood means bleeding with faces from anus and indicates all the three cases such as blooding before and after evacuation, evacuation of feces mixed with blood, and simple melena. The main causes are fire(火) and deficiency of spleen qi (脾氣虛). According to the color of fecal blood and the region of the bleeding, first, if the blood color is dark-red and blood discharges after emptying the bowels, it is called deposited poison into Jang(臟毒) or distant bleeding(遠血), and if the color of blood is clear and bowel emptying occurs after bleeding, it is bloody stool due to intestinal wind(腸風) or nearby bleeding(近血). For treating methods(治法). removing heat from the blood and stopping bleeding(淸熱凉血止血), removing dampness and stopping bleeding(淸熱除濕止血), invigorating Ki for promoting Hul-controJ(益氣攝血), warming the spleen and stomach to dispel cold and stopping bleeding(溫中散寒止血) etc are applied. As for the treating prescriptionl(治法), a Hwangtotang(黃土湯). Jeoksodudanggwitang(赤小豆當歸散). Gwihwasan(槐花散). Wipungtang(胃風湯). Hwangnyeonhwan modifying(黃連丸加減). Samultang modifying(四物湯加減). Paedoksan modifying(敗毒散加減) etc are used. As for acupuncture and moxibustion(鍼灸療法). if etiology(病因) is damp-heat(濕熱), acupuncture(刺鍼) at Janggang(長强); Charyo(BL 32); Sangeoheo(ST 37)(上巨虛); Seungsan(BL 57)(承山穴), and in case of deficiency of spleen Gi(脾氣虛), acupunture(刺鍼) with tonification(補法) at I Baek(EX-UE 2)(二白); Gwanwon(CC 4)(關元); Joksamni(ST 36)(足三里) Taebaek(SP 3)(太白); Hoeeum(CC 1)(會陰穴), or mxibuston(灸) at Baekoe(GC 2O)(百會); Myeongmun9GC (命門) or the point of opposite to umbilicus among spinal vertebrae(脊中對臍穴) are used. The external treatment(外治療法) was consisted of plastering umbilicus therapy(敷臍法) and enema therapy(灌腸法).

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.16 no.6
• /
• pp.1195-1204
• /
• 1992

The natural convection from upward and downward facing horizontal isothermal plate immersed in water is studied numerically. The temperature of the plate is from 0.0 .deg. C to 8.0 .deg. C and the ambient water temperature is from 1.0 .deg. C to 10.0 .deg. C. Numerical results are presented for the velocity profiles, temperature profiles, local heat transfer coefficients, and average Nusselt numbers over the entire flow fields. Flow patterns are shown in the upward and downward facing surfaces at different ambient water temperatures. For the upward facing surface, there are upflow and unsteady flow. And the regions of the ambient water temperatures which give rise to the upflow are more extensive as the temperatures of the isothermal surface become more distant from the density extremum temperature. For the downward facing surface, only the downflow region is shown. For the upward facing horizontal isothermal surface, the average Nusselt number(= N $u_{1}$$^{*}$) is 28.86(Ra)$^{0.01}$. And for the downward facing surface, the average Nusselt number(= N $u_{2}$$^{*}$) is $C_{2}$(Ra)$^{0.2}$ and the values of $C_{2}$ are enlarged in the range of 0.785 .leq. $C_{2}$ .leq. 1.250 as increasing of the temperatures of the isothermal surface.ace.ace.

• Journal of Energy Engineering
• /
• v.2 no.3
• /
• pp.268-275
• /
• 1993

A series of parametric investigations are performed in order to resolve the flow characteristic of a Quebec city stoker incinerator. The parameters considered in this study are five internal configurations of the Quebec city stoker itself and its modified ones, primary air velocity, the injection velocity and angle of the secondary air, and the reduction of the stoker exit area. A control-volume based finite-difference method by Patankar together with the power-law scheme is employed for discretization. The resolution of the pressure-velocity coupling is made by the use of SIMPLEC algorithm. The standard, two equation, k-$\varepsilon$ model is incorporated for the closure of turbulence. The size of recirculation region, turbulent viscosity, the mass fraction of the secondary air and pressure drop are calculated in order to analyze the characteristics of flow field. The results are physically acceptable and discussed in detail. The flow field of the Quebec city stoker shows the strong recirculation zone together with the high turbulence intensity over the upper part of the incinerator.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.7 no.3
• /
• pp.259-267
• /
• 2005

This paper analyzed characteristic of temperature change as well as bottom of tunnel with thermometer according to tunnel length and region during one year. And it measured temperature distribution near tunnel portal. In the paper it was known that tunnel entrance and exit have different characteristic temperature distribution in accordiance with bottom of tunnel per tunnel length. Temperature of tunnel changed from tunnel exit to fifty meter and distribution of tunnel temperature was established uniform regardless of tunnel length. But temperature distribution of tunnel changed in tunnel entrance differ from tunnel exit in the location of one hundred twenty five meter and one hundred fifty meter. Cold air inflowed from tunnel entrance have influenced with the location of one hundred twenty five meter and one hundred fifty meter.

• The Korean Journal of Physiology and Pharmacology
• /
• v.13 no.3
• /
• pp.257-263
• /
• 2009

This study aimed to investigate whether selective serotonin reuptake inhibitors (SSRIs) attenuate brain injury and facilitate recovery following photothrombotic cortical ischemia in mice. Male ICR mice were anesthetized and systemically administered Rose Bengal. Permanent focal ischemia was induced in the medial frontal and somatosensory cortices by irradiating the skull with cold light laser. The animals were treated with fluoxetine or sertraline once a day for 14 d starting 1 h after ischemic insult. Treatment with fluoxetine and sertraline significantly reduced the infarct size. The Evans blue extravasation indices of the fluoxetine- and sertraline-treated groups were significantly lower than that of the vehicle group. Treatment with fluoxetine and sertraline shifted the lower limit of the mean arterial blood pressure for cerebral blood flow autoregulation toward normal, and significantly increased the expression of heme oxygenase-1 (HO-1) and hypoxia-inducible factor-1 ${\alpha}$ (HIF-1 ${\alpha}$) proteins in the ischemic region. These results suggest that SSRIs, such as fluoxetine and sertraline, facilitate recovery following photothrombotic cortical ischemia via enhancement of HO-1 and HIF-1 ${\alpha}$ proteins expression, thereby providing a benefit in therapy of cerebral ischemia.