• Clinical and Experimental Pediatrics
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• v.59 no.sup1
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• pp.25-28
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• 2016

Phelan-McDermid syndrome is a rare genetic disorder caused by the terminal or interstitial deletion of the chromosome 22q13.3. Patients with this syndrome usually have global developmental delay, hypotonia, and speech delays. Several putative genes such as the SHANK3, RAB, RABL2B, and IB2 are responsible for the neurological features. This study describes the clinical features and outcomes of Korean patients with Phelan-McDermid syndrome. Two patients showing global developmental delay, hypotonia, and speech delay were diagnosed with Phelan-McDermid syndrome via chromosome analysis, fluorescent in situ hybridization, and multiplex ligation-dependent probe amplification analysis. Brain magnetic resonance imaging of Patients 1 and 2 showed delayed myelination and severe communicating hydrocephalus, respectively. Electroencephalography in patient 2 showed high amplitude spike discharges from the left frontotemporoparietal area, but neither patient developed seizures. Kidney ultrasonography of both the patients revealed multicystic kidney disease and pelviectasis, respectively. Patient 2 experienced recurrent respiratory infections, and chest computed tomography findings demonstrated laryngotracheomalacia and bronchial narrowing. He subsequently died because of heart failure after a ventriculoperitoneal shunt operation at 5 months of age. Patient 1, who is currently 20 months old, has been undergoing rehabilitation therapy. However, global developmental delay was noted, as determines using the Korean Infant and Child Development test, the Denver developmental test, and the Bayley developmental test. This report describes the clinical features, outcomes, and molecular genetic characteristics of two Korean patients with Phelan-McDermid syndrome.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.167-175
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• 2018

Natural gas is a clean fuel that discharges almost no air-contaminating substances. This study examined the simultaneous reduction of $CH_4$ and NOx of NGOC/LNT catalysts for CNG buses related to the improvement of the $de-CH_4/NOx$ performance, focusing mainly on identifying the additive catalysts, loading of the washcoat, stirring time, and types of substrates. The 3wt. % Ni-loaded NGOC generally exhibited superior $CH_4$ reduction performance through $CH_4$ conversion, because Ni is an alkaline, toxic oxide, and exerts a reducing effect on $CH_4$. A excessively small loading resulted in insufficient adsorption capacity of harmful gases, whereasa too high loading of washcoat caused clogging of the substrate cells. In addition, with the economic feasibility of catalysts considered, the appropriate amount of catalyst washcoat loading was estimated to be 124g/L. The NOx conversion rate of the NGOC/LNT catalysts stirred from $200^{\circ}C$ to $550^{\circ}C$ for 5 hours showed 10-15% better performance than the NGOC/LNT catalysts mixed for 2 hours over the entire temperature range. The NGOC/LNT catalysts exhibitedapproximately 20% higher $de-CH_4$ performance on the ceramic substrates than on the metal substrates.

• Journal of Korea Water Resources Association
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• v.46 no.9
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• pp.921-932
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• 2013

Runoff data availability is a substantial factor for precise flood control such as flood frequency or flood forecasting. However, runoff depths and/or peak discharges for small watersheds are rarely measured which are necessary components for hydrological analysis. To compensate for this discrepancy, a lumped concept such as a Storage Function Method (SFM) was applied for the partitioned Choongju Dam Watershed in Korea. This area was divided into 22 small watersheds for measuring the capability of spatial extension of runoff data. The chosen total number of flood events for searching parameters of SFM was 21 from 1991 to 2009. The parameters for 22 small watersheds consist of physical property based (storage coefficient: k, storage exponent: p, lag time: $T_l$) and flood event based parameters (primary runoff ratio: $f_1$, saturated rainfall: $R_{sa}$). Saturated rainfall and base flow from event based parameters were explored with respect to inflow at Choongju Dam while other parameters for each small watershed were fixed. When inflow of Choongju Dam was optimized, Youngchoon and Panwoon stations obtained average of Nash-Sutcliffe Efficiency (NSE) were 0.67 and 0.52, respectively, which are in the satisfaction condition (NSE > 0.5) for model evaluation. This result is showing the possibility of spatial data extension using a lumped concept model.

• Journal of Korea Water Resources Association
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• v.35 no.5
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• pp.525-539
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• 2002

Effects of Yongdam Dam discharge conditions on water quality of the Keum River and Daechung Lake inflow were analyzed for various scenarios using WASP5 water quality model. Three different groups of scenarios were tested: 1) Two different weather conditions; the lowest flow year and the highest flow year since the beginning of Daechung Dam operation in 1981, 2) Fine discharge flow rates; 5.4, 8.9, 12.4, 16.4 ㎥/s and field observed flow during the study period, 3) Three conditions of discharge water quality; first grade, second grade by Korean water quality standard and field observed water quality. Effect of changes in Yongdam Dam discharges was greater for dry year. The increase of discharge from the Yongdam Dam will improve water quality of downstream areas only when the water quality of the discharge is equal or better than that of downstream areas. Field observed water qualify data show that BOD concentrations are lower than first grade level but TN and TP concentrations are exceeding 5th and 3rd grade level in Korean standard, respectively. Considering that nutrient control methods in watershed areas of Yongdam dam are limited, it is expected that nutrient concentrations from Yongdam Dam discharge will be higher than 2nd grade water quality standard level. Therefore, it would be important to develop practical management strategies in the watershed area of Yongdam Dam based on field conditions for conservation of water quality in downstream areas.

• Journal of Korea Water Resources Association
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• v.49 no.5
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• pp.451-458
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• 2016

In order to infer regional flood frequency for ungauged watersheds, index flood method was applied for this study. To pursuit this given purpose, annual peak flood data for 22 watersheds located at the upstream of the Chungju Dam watershed were obtained from the spatial extension technique. The regionalization of mean annual flood was performed from extended flood data at 22 points. Based on the theory that flood discharge and watershed size follows the power law the regionalization generated the empirical relationship. These analyses were executed for the full size of the Chungju Dam watershed as one group and three different mid-size watersheds groups. From the results, the relationship between mean annual flood and watershed sizes follow the power law. We demonstrated that it is appropriate to use the relationship between specific flood discharges from the upper and lower watersheds in terms of estimating the floods for the ungaged watersheds. Therefore, not only the procedure of regional frequency analysis but also regionalizaion analaysis using finer discretization of the regions interest with respect to the regional frequency analyisis for the ungauged watersheds is important.

• Journal of Korea Water Resources Association
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• v.48 no.3
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• pp.209-220
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• 2015

In this study, the effects of changed environment on spatial extension of flood discharge data which is generating discharge data at ungauged watersheds. Especially, effects of dams on spatial extensions of flood discharge data and on natural flow generation were studied. This is somehow an intial trial of flood discharge data generation for heterogeneous watersheds because of dam installation. Data extensions have been performed based on the flood discharge data from YeoJoo water gauge station located on the Nam-Han River. For the evaluation of flood discharge data spatial extension under dam effects and producing natural flow, 41 flood events associated with YeoJoo water gauge station were selected from 1986 to 2010. When flood discharge data were extended based on YeoJoo water gauge station, 77% of selected flood events were over the satisfaction ranges (NSE>0.5) of Nash-Sutcliffe Efficiency for model validation. Extended flood discharge data at Yangpyung has 0.84 NSE obtained from spatial data extension based on YeoJoo water gauge station. Generated natural flow at YeoJoo was influenced strongly by Chungju Dam which has larger effects on streamflow at YeoJoo than Hoangsung Dam. Observed peak discharges after the 1986 of Chungju Dam installation were smaller than those of the obtained natural flow. Through these results, spatial extension of flood discharge data with installed dams works efficiently for ungauged watersheds and natural flow can be generated using extended flood discharge data.

• Journal of Korea Water Resources Association
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• v.48 no.3
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• pp.185-196
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• 2015

A conceptual watershed model HSPF (Hydrological Simulation Program-Fortran) was applied to the Hwangryong river watershed to evaluate climate change effects on pollution loads of the river. For modeling purposes, the Hwangryong river watershed was divided into 7 sub-watersheds. The model was calibrated and validated for the river discharges against the data observed in 2011 at several monitoring stations. The RCP scenarios were set up for the model simulations after being corrected by change factor method. The simulation results of the RCP 4.5 scenario indicate that the annual river discharge and concentrations of BOD, TN, TP of the Hwangryong river will continually increase during the second-half of the 21st century. As for the RCP 8.5 scenario, the simulations results imply that the pollution loads will increase during the middle of the 21st century reflecting the pattern of precipitation. Monthly distributions of the pollution loads for the RCP 4.5 and the RCP 8.5 scenarios show it will increase the most in September and February, respectively.

• Journal of Korea Water Resources Association
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• v.40 no.12
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• pp.957-968
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• 2007

It is essential to obtain accurate and highly reliable streamflow data for quantitative management for water resources. Thereafter such real-time streamflow gauging methods as ultrasonic flowmeter and index-velocity are introduced recently. Since these methods calculate flowrate through entire cross-section by measuring partial velocities of it, rational and theoretical basis are necessary for accurate estimation of discharge. The purpose of the present study lies in analysis on the applicability of Chiu#s(1987, 1988) two dimensional velocity distribution equations by applying them to natural rivers and by comparing simulated velocity distributions with observed ones obtained with ADCP. Maximum and mean velocities are calculated from observed data to estimate entropy parameter M. Such isovel shape parameters as h and $\beta_i$ are estimated by object function based on least squares criterion. In case optimized parameters are applied, Chiu#s velocity distributions fairly well simulate observed ones. By using 14 simulated data sets which have relatively high correlation coefficients, properties of parameters are analyzed and h, $\beta_i$ are estimated for velocity-unknown river sections. When estimated parameters are adopted for verification, simulated velocity distributions well reproduce real ones. Finally, calculated discharges display rough agreement with measured data. The results of the present study mean that if parameters related are properly estimated, Chiu#s velocity distribution is likely to reproduce the real one of natural rivers.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.2
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• pp.50-59
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• 2020

Superabsorbent Polymer (SAP) expands inside concrete by absorbing water and contracts as it discharges water. Through this process, concrete can achieve the internal curing effect, but the space occupied by the expanded SAP remains as a void. In this study, the effects of SAP internal curing and voids were evaluated by evaluating the fundamental properties and chloride penetration resistance of SAP mixed concrete. Also, to evaluate the internal curing effect by SAP, the tests were carried out under water and sealed curing conditions, respectively. From the result, the compressive strength of water curing did not differ significantly according to the mixing ratio of SAP. In the case of sealed curing, however, the compressive strength tended to increase as the mixing ratio of SAP increased. The internal curing effect of sealed curing was considered to have influenced the increase in compressive strength. In the case of the chloride diffusion coefficient, the diffusion coefficient tended to decrease as the mixing ratio of SAP increased. In particular, as the sealed curing is applied, the chloride penetration resistance is further improved due to internal curing effect. If the curing conditions are different, it is considered inappropriate to estimate the chloride penetration resistance by the surface electrical resistivity.

• Ocean and Polar Research
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• v.23 no.2
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• pp.109-119
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• 2001

Meiobenthic community structure of tidal flats near the Yeonggwang Nuclear Power Plant have studied during summer (June) and fall (October) 1997. Examination of sediment samples collected along the transects showed that there were 18 different types of meiobenthos in the study area. The most abundant meiobenthic animals belonged to Phylum Nematoda in both seasons and all transects. However, sediment samples collected near discharge areas, transects A and B, showed relatively lower abundance than other general coastal areas. Another abundant meiobenthic organism is benthic Harpacticoids which is very sensitive to any environmental changes. Polycheats and Ostracods were next abundant meiobenthos which also showed the difference between the study area and other general coastal areas. Only transect C maintained similar meiobenthic abundance and diversity to other coastal areas. Horizontal distribution for transects A and B showed higher densities in upper and mid tidal flat zones. On the other hand, transect C which is located furtherest from the discharges showed an increasing trend in abundance from upper to lower areas. For size distribution analyses showed that animals which fit into the meshsize of 0.125 mm were abundant, Vertical distribution of meiobenthic animals within the sediments for both sampling seasons showed the highest individual numbers in the surface sediment layers of 0-1 cm depth and showed a decreasing trend as sediment gets deeper. Each class of meiobenthos had different vertical profiles. When comparing survey transects A and B with other similar tidal flat areas, this sites seems to a very unstable environment of tidal flats near the Yeonggwang Nuclear Power Plant.