• Atmosphere
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• v.30 no.4
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• pp.421-437
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• 2020

The effects of the terminal fall velocity-diameter relationship for raindrops, which is prescribed based on the measurement, on the simulated surface precipitation over Korea during summer season were investigated in our study. Two rainfall cases, 1-month summer precipitation and mesoscale rainfall, have been simulated using the Weather Research and Forecasting (WRF) model. The selected cloud microphysics parameterizations are WRF Single-Moment 5-class (WSM5) and WRF Single-Moment 6-class (WSM6) in the WRF model. The measured terminal fall-diameter relationship for raindrops by Gunn and Kinzer (1949) was applied in both WSM5 and WSM6. The sensitivity experiments with WSM5 and WSM6, applying the measured fall-diameter relationship, presents the different responses in simulated precipitation amount for the 1-month summer precipitation case. Precipitation increases with WSM5, thus enhancing the precipitation statistical skills. However, precipitation decreases with WSM6 leading to the deterioration of precipitation statistical skills. For the mesoscale rainfall case, precipitation increases with both WSM5 and WSM6, which further enhances the positive bias in precipitation amount.

• Journal of the Korean earth science society
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• v.41 no.1
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• pp.1-18
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• 2020

This study presented the effects of the assumed mass-size relationship for snow on the simulated surface precipitation by using cloud microphysics parameterizations in Weather Research and Forecasting (WRF) model. The selected cloud microphysics parameterizations are WRF Double-Moment 6-class (WDM6) and WRF Single-Moment 6-class (WSM6) in the WRF model. We replaced the mass-size relationship for snow in WDM6 and WSM6 with Thompson's mass-size relationship retrieved from measurement data. The sensitivity of the modified WDM6 and WSM6 was tested for the idealized 2-dimensional squall line and winter precipitation system over the Korean peninsula, respectively. The modified WDM6 and WSM6 resulted in the increase of graupel/rain mixing ratios and the decrease of snow mixing ratio in the low atmosphere. The changes of hydrometeor mixing ratio and surface precipitation could be due to the collision-coalescence process between raindrops and snow and the graupel melting process.

• Journal of Korean Society of Rural Planning
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• v.14 no.2
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• pp.55-64
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• 2008

This study aims to analyze the sensitivity of WSM(weighted scenario method)-AHP method according to variation of nonlinear exponent for accessibility criteria, which are used to make urbanization potential maps with the optimal weighting value for multiple criteria in grid-based GIS technique. Besides this study tried to develop WSM-AHP2 which is simplified by using rank of the potential value for each scenario. The two methods were applied to the test area, Suwon city located south area of Seoul, with time series land-use maps of 1986 and 1996. The evaluation system of urbanization potential have 7 criteria including 6 accessibility criteria. The results of WSM-AHP2, the optimal weighting values and their corresponding potential maps, have almost similar with those of WSM-AHP. In the application of CA(cellular automata) model for expansion of urbanized area using the three potential maps by WSM-AHP, WSM-AHP2, and specialists's AHP evaluation, it also showed that the accuracy of simulation for actual urban area is the highest in the potential map of WSM-AHP, followed by WSM-AHP2 and specialists's AHP evaluation. From the results of this study, WSM-AHP and simplified WSM-AHP2 will be used to generate the optimal potential maps for land-use planning in urban fringe area.

• Food Science and Preservation
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• v.15 no.6
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• pp.903-908
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• 2008

This study investigated protein changes in soymilk and whole soymilk due to enzymatic hydrolysis. The total free amino acid contents of low molecular weight soymilk (LSM) and low molecular weight whole soymilk (LWSM) were higher than soymilk (SM) and whole soymilk (WSM). The essential amino acid content was similar in SM and LSM, but was higher in LWSM than WSM. In SDS-PAGE performed to tendency of becoming low molecules, the soy protein molecular weights were 3372 kDa for SM and WSM, but 17 kDa or less for LSM and LWSM. Also, high molecular weight protein spots were evident in 2-D electrophoresis of SM and LSM, but only low molecular weight protein spots of various sizes were evident in WSM and LWSM. This suggests that the high molecular weight protein in SM and WSM is changed to low molecular weight protein by enzymatic hydrolysis. Further investigations of the separation and qualities of these proteins are required.

• Food Science and Preservation
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• v.15 no.3
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• pp.361-366
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• 2008

This study was investigated the functional characteristic change by the enzymatic hydrolysate to improve the functionality of soybean milk. The soymilk (SM), hydrolysates of soy milk (HSM), whole soy milk (WSM) and hydrolysates of whole soy milk (HWSM) revealed composition difference whether the bean-curd removal was included or not, but nearly no change was found by the low molecule enzyme treatment. The chromaticity revealed clear difference whether the bean-curd was removed or not, but did not show any difference by the hydrolyzation. Total free sugar and oligosaccharide content was found to be 1,389.88 mg% in SM, 1,013.51 mg% in HSM, 1,539.51 mg% in WSM, and 1,331.53 mg% in HWSM by showing the reduction after the enzyme hydrolyzation. DPPH free radical scavenging activity revealed to show high activity in HSM and in HWSM which were enzymatically hydrolyzed by 49.26% and 45.34%, respectively. And the ACE inhibition activity of HSM and HWSM was found to be approximately 1.6 times higher than the control SM and HSM The superoxide radical scavenging activity revealed to show high activity at HSM and HWSM, and no difference was found by the removal of bean-curd from raw soybean. Based upon these results, the functional characteristics of HSM, WSM and HWSM were found to be excellent compared to SM and it is expected to be used as various functional sources in a future.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.674-683
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• 2017

The frequency and intensity of soil moisture stress associated with climate change has increasing, and the stability of field crop cultivation has decreasing. This experiment was conducted to investigate the effect of soil moisture management method on growth and yield of corn. Soil moisture was managed at the grade of WSM (wet soil moisture, 34.0~42.9%), OSM (optimum soil moisture, 27.8~34.0%), DSM (dry soil moisture, 20.3~27.8%), and ESM (extreme dry moisture, 16.6~20.3%) during V8 (8th leaf stage)-VT (tasseling stage). After VT, irrigation was limited. The treated amount of irrigation was 54.1, 47.7, 44.0 and 34.5% of total water requirement, respectively. The potential evapotranspiration during the growing period was $3.29mm\;day^{-1}$, and upward movement of soil water was estimated by the AFKAE 0.5 model in the order of ESM, DSM, OSM, and WSM. We could confirm this phenomenon from actual observations. There was no significant difference in leaf characteristics, dry matter, and primary productivity depending on the level of soil moisture, but leaf development was delayed and dry weight decreased in DSM. However, dry weight and individual productivity of DSM increased after irrigation withdrawal compared to that of OSM. In DSM, ear yield and number of kernels per ear decreased, but water use efficiency and harvest index were higher than other treatments. Therefore, it is considered that the soil moisture is concentratedly managed before the V8 period, the V8-VT period is controlled within the range of 100 to 500 kPa (20.3~27.8%), and no additional irrigation is required after the VT.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.172-172
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• 2011

The interaction between land surface and atmosphere is essentially affected by hydrometeorological variables including soil moisture. Accurate estimation of soil moisture at spatial and temporal scales is crucial to better understand its roles to the weather systems. The KLDAS(Korea Land Data Assimilation System) is a regional, specifically Korea peninsula land surface information systems. As other prior land data assimilation systems, this can provide initial soil field information which can be used in atmospheric simulations. For this study, as an enabling high-resolution tool, weather research and forecasting(WRF-ARW) model is applied to produce precipitation data using GFS(Global Forecast System) with GFS embedded and KLDAS soil moisture information as initialization data. WRF-ARW generates precipitation data for a specific region using different parameters in physics options. The produced precipitation data will be employed for simulations of Hydrological Models such as HEC(Hydrologic Engineering Center) - HMS(Hydrologic Modeling System) as predefined input data for selected regional water responses. The purpose of this study is to show the impact of a hydrometeorological variable such as soil moisture in KLDAS on hydrological consequences in Korea peninsula. The study region, Chongmi River Basin, is located in the center of Korea Peninsular. This has 60.8Km river length and 17.01% slope. This region mostly consists of farming field however the chosen study area placed in mountainous area. The length of river basin perimeter is 185Km and the average width of river is 9.53 meter with 676 meter highest elevation in this region. We have four different observation locations : Sulsung, Taepyung, Samjook, and Sangkeug observatoriesn, This watershed is selected as a tentative research location and continuously studied for getting hydrological effects from land surface information. Simulations for a real regional storm case(June 17~ June 25, 2006) are executed. WRF-ARW for this case study used WSM6 as a micro physics, Kain-Fritcsch Scheme for cumulus scheme, and YSU scheme for planetary boundary layer. The results of WRF simulations generate excellent precipitation data in terms of peak precipitation and date, and the pattern of daily precipitation for four locations. For Sankeug observatory, WRF overestimated precipitation approximately 100 mm/day on July 17, 2006. Taepyung and Samjook display that WRF produced either with KLDAS or with GFS embedded initial soil moisture data higher precipitation amounts compared to observation. Results and discussions in detail on accuracy of prediction using formerly mentioned manners are going to be presented in 2011 Annual Conference of the Korean Society of Hazard Mitigation.