• Journal of Korean Society for Atmospheric Environment
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• v.32 no.4
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• pp.422-434
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• 2016

This study was conducted to understand roles of $NO_x(=NO+NO_2)$ on high $O_3$ episodes at an urban monitoring station in Seoul. Concentrations of NO, $NO_2$, $NO_y$ and $O_3$ were measured intensively at KIST monitoring station which located at urban center in Seoul metropolitan area during May 18~June 13, 2015. Sampling period was planed because high $O_3$ and PM occurred frequently during from late spring to early summer months in Seoul. The experimental site locates in NW from center of Seoul and is surrounded by residential area. Belt highway of the city runs from north to west side nearby experimental site. Vehicle exhaust emissions due to heavy traffic influenced $NO_x$ concentration at the site during northwesterly wind. Specific $NO_2$ concentration was measured by Blue Light photolytic converter, and it was compared to $NO_2$ concentration measured by molybedenum converter. $[NO_2]_{phtolysis}$ was usually lower than $[NO_2]_{molybedenum}$ during the experiment period; however their diurnal variations were very similar. The linear relationship between these $NO_2$ concentrations was found to be $[NO_2]_{phtolysis}$=0.64 $[NO_2]_{molybedenum}$ - 2.6, $r^2$=0.83 during May 16~8, 2015. The difference between $NO_2$ by molybdenum converter and by photolytic converter (${\Delta}NO_2=[NO_2]_{molybedenum}-[NO_2]_{phtolysis}$) accounted for residual $NO_y$ which can represent $NO_z$ (=$NO_y-NO_x$). $O_3$ concentration showed typical daily trend which has maximum at late afternoon and minimum during the night. $O_3$ increased at a rate of 7 ppb/hr since 8 am. and reached the maximum concentration (~80 ppb) at 3 pm.. The diurnal pattern of $O_3$ was inversely related with that of $NO_2$, suggesting that the formation of $O_3$ was the result of photochemical activity of $NO_2$.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.4
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• pp.344-353
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• 2016

The cause of abnormal tidal residuals was examined by analyzing sea levels, sea surface atmospheric pressures, winds at ten tide stations, and current, measured at the coast of the Yellow Sea from the night of November $24^{th}$ to the morning of the $25^{th}$ in 2013, along with weather chart. Additionally, the cross-correlations among the measured data were also examined. The 'abnormal tidal residuals' mentioned in this study refer to differences between maximum and minium tidal residuals. The largest abnormal tidal residual was identified to be a difference of 176 cm occurring over 4 hours and 1 minute at YeongJongDo (YJD) with a maximum tidal residual of 111 cm and minimum of -65 cm. The smallest abnormal tidal residual was 68 cm at MoSeulPo (MSP) during 8 hours 52 minutes. The cause of these abnormal tidal residuals was not a meteo-tsunami generated by an atmospheric pressure jump but wind generated by the pressure patterns. The flow speed due to these abnormal tidal residuals as measured at ten tide stations was not negligible, representing 16 ~ 41 % of the annual average ebb current speed. From the cross correlation among the tidal residuals, winds, and tidal residual currents, we learned the northern flow, due to southerly winds, raised the sea level at Incheon when a low pressure center located on the left side of the Korean Peninsula. After passing the Korean Peninsula, a southern flow due to northerly winds decreased the sea level.

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.1
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• pp.17-24
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• 2009

This study was conducted to find out the effects of relationship between ocean-meteorological factors and snowfall at Incheon, Gunsan and Mokpo when cold and dry continental air mass passed through the West Sea of Korea in winter. Mean snowfall from December to February showed the order of Gunsan (12.7 cm), Mokpo (9.0 cm) and Incheon (7.8 cm). In particular, the snowfall in the three regions showed the regional difference in December and February. It was well consistent with the extension of continental high. Extension of continental high can cause effect on snowfall at the west regions (Inchoen, Gunsan, Mokpo) of the Korean Peninsula. The continental high extended from the southern China to western coastal region of the Korean Peninsula in December, it extended from the northern China to central area of the Korean Peninsula in January. It also extended from the north side of China through Bohai Sea and Yodong Peninsula to central area of the Korean Peninsula in February. Therefore, more snowfall recorded in Incheon is higher in February than December whereas Gunsan and Mokpo is the opposite. The heavy snowfall at the three regions was caused by loss of the heat from the ocean to air when the heat loss was higher than 100 $W/m^2$. The heavy snowfall was also observed when the arrangement of continental high atmospheric pressure and low pressure was high at the west and low at the east, which formed a front in West and when the wind blow from the North or North West at the speed of 4${\sim}$8 m/sec.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.5
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• pp.497-512
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• 2017

Temporal and spatial variations in surface water temperature were studied using data from temperature monitoring buoys deployed at 47 stations around Boryeong from 2011-2012 off the west coast of Korea. Temperature fluctuations are predominant at diurnal and semidiurnal periods for all seasons, and their amplitudes are large in spring and summer but small in autumn. The maximum annual change in air temperature takes place on August 2nd and August 22th for water temperature, which means the phase for air temperature precedes water temperature by 20 days. The diurnal period of water temperature fluctuation is predominant around Daecheon and Muchangpo Harbors, with the semidiurnal period around Wonsan Island, and the shallow water constituent period on the estuary around Daecheon River. On the whole, air and water temperatures fluctuate with wind. Spectral analyses of temperature records show significant peaks at the 0.5, 1 and 15 day marks with 7-10 day periods of predominant fluctuations. Cross-correlation analyses for the temperature fluctuation show that the waters around Boryeong can be classified into four areas: a mixed water zone around the southeast side of Wonsan Island, an off-shore area to the west, an off-shore area to the south and a coastal area along the shore from Song Island to Muchangpo Harbor.

• Journal of Physiology & Pathology in Korean Medicine
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• v.34 no.2
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• pp.102-116
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• 2020

The purpose of this study was to analyze the research trends of randomized controlled trials on herbal medicine treatment for atopic dermatitis in China for the last 5 years. We searched for randomized controlled trials with the intervention of herbal medicine for the treatment of atopic dermatitis in the CNKI (China National Knowledge Infrastructure) from January 2014 to December 2018. For the screening of the paper, we used '特应性皮炎' and '异位性皮炎' which mean atopic dermatitis and search was limited to three areas within Medicine & Public Health: Traditional Chinese Medicine, Traditional Chinese Medicinal Herbs, Combination of Traditional Chinese Medicine with Western Medicine. Among the 136 searched studies, we selected a total of 34 studies and analyzed a year of publication, subject characteristics, study design and intervention, prescribed herbal medicine and herbs, pattern identification, evaluation criteria, and outcomes. Longmu decoction (龍牡湯) and Polia Sclerotium (茯笭) was the most frequently prescribed medicine and herb. The most commonly used pattern identification was Blood deficiency and Wind-dryness (血虛風燥), and among them, the most frequently prescribed herb is Rehmanniae Radix (生地黃). In most studies using the total effectiveness and SCORAD index as an outcome measure, the herbal medicine treatment group showed statistically better results than the control group. As a result of the safety assessment, the herbal medicine treatment group was reported having significantly fewer side effects compared to the control group. Hence, it was confirmed that the intervention including herbal medicine had a significant effect on atopic dermatitis. This study would be able to provide the basis of clinical research on atopic dermatitis and applied to the treatment of atopic dermatitis.

• Smart Structures and Systems
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• v.4 no.2
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• pp.221-232
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• 2008

This paper represents the final results of a research program sponsored by the European Commission through project WIND-CHIME ($\underline{W}$ide Range Non-$\underline{IN}$trusive $\underline{D}$evices toward $\underline{C}$onservation of $\underline{HI}$storical Monuments in the $\underline{ME}$diterranean Area), in which the possibility of using advanced seismic protection technologies to preserve historical monuments in the Mediterranean area is investigated. In the current research, the dynamic characteristics of two outstanding Mamluk-Style minarets, which similar minarets were reported to experience extensive damage during Dahshur 1992 earthquake, are investigated. The first minaret is the Qusun minaret (1337 A.D, 736 Hijri Date (H.D)) located in El-Suyuti cemetery on the southern side of the Salah El-Din citadel. The minaret is currently separated from the surrounding building and is directly resting on the ground (no vaults underneath). The total height of the minaret is 40.28 meters with a base rectangular shaft of about 5.42 ${\times}$ 5.20 m. The second minaret is the southern minaret of Al-Sultaniya (1340 A.D, 739 H.D). It is located about 30.0 meters from Qusun minaret, and it is now standing alone but it seems that it used to be attached to a huge unidentified structure. The style of the minaret and its size attribute it to the first half of the fourteenth century. The minaret total height is 36.69 meters and has a 4.48 ${\times}$ 4.48 m rectangular base. Field investigations were conducted to obtain: (a) geometrical description of the minarets, (b) material properties of the minarets' stones, and (c) soil conditions at the minarets' location. Ambient vibration tests were performed to determine the modal parameters of the minarets such as natural frequencies and mode shapes. A $1/16^{th}$ scale model of Qusun minaret was constructed at Cairo University Concrete Research Laboratory and tested under free vibration with and without SMA wire dampers. The contribution of SMA wire dampers to the structural damping coefficient was evaluated under different vertical loads and vibration amplitudes. Experimental results were used along with the field investigation data to develop a realistic 3-D finite element model that can be used for seismic risk evaluation of the minarets. Examining the updated finite element models under different seismic excitations indicated the vulnerability of such structures to earthquakes with medium to high a/v ratio. The use of SMA wire dampers was found feasible for reducing the seismic risk for this type of structures.

• Journal of Environmental Science International
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• v.19 no.3
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• pp.295-304
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• 2010

Actual evapotranspiration (AET) in the Suyeong-gu was estimated and correlations between AET and meteorological factors were analyzed. The study area was Suyeong-gu lay at the east longitude $129^{\circ}$ 05' 40" ~ 129$^{\circ}$ 08' 08" and north latitude $35^{\circ}$ 07' 59" ~ $35^{\circ}$ 11' 01". The Kumryun mountain, the Bae mountain, the Suyeong river and the Suyeong bay are located on west, north, northeaster and south side in the study area, respectively. AET was estimated using precipitation (P), potential evapotranspiration (PET) and plant-available water coefficient. Meteorological factors to estimate PET were air temperature, dewpoint temperature, atmospheric pressure, duration of sunshine and mean wind speed (MWS). PET and AET were estimated by a method of Allen et al. (1998) and Zhang et al. (2001), respectively. PET was the highest value (564.45 mm/yr) in 2002 year, while it was the lowest value (449.95 mm/yr) in 2003 year. AET was estimated highest value (554.14 mm/yr) in 2002 year and lowest value (427.91 mm/yr) in 2003 year. Variations of PET and AET were similar. The linear regression function of AET as PET using monthly data was AET=0.87$\times$PET+3.52 and coefficient of determination was high, 0.75. In order to analyze relationship between the evapotranspiration and meteorological factors, correlation analysis using monthly data were accomplished. Correlation coefficient of AET-PET was 0.96 high, but they of AET-P and PET-P were very low. Correlation coefficients of AET-MWS and PET-MWS were 0.67 and 0.73, respectively. Thus, correlation between evapotranspiration and MWS was the highest among meteorological factors in Suyong-gu. This means that meteorological factor to powerfully effect for the variation of evapotranspiration was MWS. The linear regression function of AET as MWS was AET=84.73$\times$MWS+223.05 and coefficient of determination was 0.54. The linear regression function of PET as MWS was PET=83.83$\times$MWS+203.62 and coefficient of determination was 0.45.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.4
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• pp.263-273
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• 2016

The effect of recirculated exhaust gas on performance and exhaust emissions with FGR rate are investigated by using a natural circulation, pressurized draft and water tube boiler with FGR system operating at several boiler loads and over fire air damper openings. The purpose of this study is to apply the FGR system to a power plant boiler for reducing $NO_x$ emissions. To activate the combustion, the OFA with 0 to 20% is supplied into the flame. When the suction damper of two stage combustion system installed in the upper side of wind box is opened by handling the lever between $0^{\circ}$ and $90^{\circ}$, also, the combustion air supplied to burner is changed. It is found that the fuel consumption rate per evaporation rate did not show an obvious tendency to increase or decrease with rising the FGR rate, and $NO_x$ emissions at the same OFA damper opening are decreased, as FGR rates are elevated and boiler loads are dropped. While a trace amount of soot is emitted without regard to the operation conditions of boiler load, OFA damper opening and FGR rate, because soot emissions are eliminated by the electrostatic precipitator with a collecting efficiency of 86.7%.

• Journal of Oriental Neuropsychiatry
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• v.26 no.4
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• pp.383-406
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• 2015

Objectives: People with tension-type headache generally take pain relievers, but long term dependency causes problems as well as side effects. The present study aimed to provide clinical evidence of herbal medicine for tension-type headache by systematic review of randomized controlled trials on the effect of herbal medicine for tension-type headache. Methods: Randomized or quasi-randomized controlled trials that verified effects of herbal medicine intervention on patients with tension-type headache were included in the study. A literature search of English, Japanese, Chinese, Korean databases was performed. The selected literature were assessed by Jadad scale and Risk of Bias. Results: Herein, 40 reports were selected from a total of 157. Meta-analyses of 2 trials indicated that the effective rate was significantly higher in the herbal medicine treatment group, as compared to the placebo control (risk ratio: 1.49, 95% confidence interval (CI): 1.23 to 1.80, p<0.0001, I²=0%). Four trials that compared herbal medicine with routine care with routine care only group showed a significantly higher effective rate of benefits for herbal medicine with routine care, as compared to routine care only (RR: 1.57, 95% CI: 1.18 to 2.10, p=0.002, I²=0%). Conclusions: The effective rate was significantly higher than control and adverse events were less in the treatment group. Pattern analysis (辨證) indicated that the studies on wind-fire pattern (風火證) were highest. Yougeun-bang (柔筋方) in prescription and Paeoniae Radix Alba (白芍藥) in medicinal herbs were most used. This finding could be widely utilized in future clinical practice and form the basis for the development of clinical practice guidelines in advance.

• Journal of Korea Water Resources Association
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• v.46 no.11
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• pp.1115-1128
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• 2013

The purpose of this study is to evaluate the suspended solids and eutrophication processes relationships in Chungju lake using CE-QUAL-W2, two-dimensional (2D) longitudinal/vertical hydrodynamic and water quality model. For water quality modeling, the lake segmentation was configured as 7 branches system according to their shape and tributary distribution. The model was calibrated (2010) and validated (2008) using 2 years of field data of water temperature, suspended solids (SS), total nitrogen (TN), total phosphorus (TP) and algae (Chl-a). The water temperature began to increase in depth from April and the stratification occurred at about 10 m early July heavy rain. The high SS concentration of the interflow density currents entering from the watershed was well simulated especially for July 2008 heavy rainfall event. The simulated concentration range of TN and TP was acceptable, but the errors might occur form the poor reflection for sedimentation velocity of nitrogen component and adsorption-sediment of phosphorus in model. The concentration of Chl-a was simulated well with the algal growth patterns in summer of 2010 and 2008, but the error of under estimation may come from the use of width-averaged velocity and concentration, not considering the actual to one side inclination by wind effect.