• Title/Summary/Keyword: Water model

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Interactions between Soil Moisture and Weather Prediction in Rainfall-Runoff Application : Korea Land Data Assimilation System(KLDAS) (수리 모형을 이용한 Korea Land Data Assimilation System (KLDAS) 자료의 수문자료에 대한 영향력 분석)

  • Jung, Yong;Choi, Minha
    • 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.

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A Study of Dexibuprofen Loaded Solid Dispersion Using Rotary Hot-melt Granulation (회전식 고온용융과립법을 이용한 덱시부프로펜 함유 고체분산체 연구)

  • Kim, Dong-Wook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.2
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    • pp.595-600
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    • 2020
  • The purpose of this paper was to prepare and evaluate solid dispersions (SD) that can increase the dissolution rate of dexibuprofen as a model drug with low solubility in water using saccharides and sugar alcohols as dispersion materials. DSC, XRD, content and content uniformity test, dissolution test, and disintegration test were conducted for physicochemical evaluation of the prepared SD. For the results, it was confirmed using differential scanning calorimetry that fructose, which has a melting point around 120 ℃ of the device operating temperature range, is a suitable excipient for the preparation of SD by the rotary hot-melt granulation (RHMG) method. X-ray diffraction analysis was conducted to confirm that the crystallinity of dexibuprofen was reduced. Disintegration test of the prepared tablet using SD-containing dexibuprofen and fructose confirmed a very fast disintegration time within 1~2 seconds and also showed that the dissolution rate was about 20% faster than that of the dexibuprofen raw material. Dexibuprofen with reduced crystallinity by SD confirmed through the RHMG method can be used to increase the dissolution rate of the drug and increase the disintegration time of the tablet. Thus, it can be used in the manufacturing of various solid preparations.

Study on the Effects of Jiaweicitaowan (加味慈桃丸) Ingredients on Angiogenic Inhibition (가미자도환(加味慈桃丸) 구성약물(構成藥物)의 혈관신생(血管新生) 억제효과(抑制效果)에 관한 연구(硏究))

  • Wang, Teh-Chung;Kang, Hee;Shim, Bum-Sang;Kim, Sung-Hoon;Choi, Seung-Hoon;Ahn, Kyoo-Seok
    • Journal of Korean Traditional Oncology
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    • v.11 no.1
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    • pp.75-93
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    • 2006
  • Jiaweicitaowan (JWCTW) has been used to inhibit recurrence and metastasis of cancer in clinical practice. Further study has shown its anti-metastatic and anti-angiogenic effects. By applying in vitro and in vivo anti-angiogenic evaluation model, the author assayed the each ingredients of JWCTW. The author performed the following experiments and the results are listed as below: Cell viability assay showed that the viability was almost identical between that of the control and that of the ingredients extract 40 ${\mu}g/m{\ell}$ treated, except of hexane fraction of Curcumae Radix (40 ${\mu}g/m{\ell}$, 2.0% of control), ethylacetate fraction (40 ${\mu}g/m{\ell}$, 26.7%), butanol fraction (20 ${\mu}g/m{\ell}$, 87.2%; 40 ${\mu}g/m{\ell}$, 12.5%) of Cremastrae appendiculatae Tuber, water fraction of Persicae Semen (40 ${\mu}g/m{\ell}$, 82.7%), ethylacetate fraction of Hippocampus (40 ${\mu}g/m{\ell}$, 85.3%). The results of gelatin zymogram assay showed that the ingredients of JWCTW decreases the gelatinolytic activity of MMP-9 from ECV304, at the concentration of 10 ${\mu}g/m{\ell}$. In in vitro invasion assay, the ingredients of JWCTW effectively inhibited the invasion of cancer cells as compared with the control (+PMA) groups. In capillary-like tube formation assay, the hexane and ethylacetate fractions of Curcumae Radix, Cremastrae appendiculatae Tuber and Persicae Semen showed the dramatic inhibition effects on tube formation of ECV304 at the concentration of 40 ${\mu}g/m{\ell}$. In ex vivo rat aortic ring assay, the hexane and ethylacetate fractions of Curcumae Radix, Cremastrae appendiculatae Tuber and Persicae Semen showed the inhibition effects on angiogenesis of rat aorta at the concentration of 40 ${\mu}g/m{\ell}$. According to the above research, the anti-angiogenic effects of the ingredients of JWCTW was proved and it suggested that the more effective prescription for anti angiogenesis could be developed.

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The Effect of UV Intensity and Wavelength on the Photolysis of Triclosan (TCS) (광반응을 이용한 Triclosan 분해에서의 UV 광세기와 파장의 효과)

  • Son, Hyun-Seok;Choi, Seok-Bong;Khan, Eakalak;Zoh, Kyung-Duk
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.9
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    • pp.1006-1015
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    • 2005
  • We investigated the effect of hydroxyl radicals on the photolysis of triclosan (TCS), which is a potent broad-spectrum antimicrobial agent. TCS degradation during the initial reaction time of 5 min followed a pseudo-first order kinetic model ai all light intensities at a wavelength of 365 nm and at the low light intensities at a wavelength of 254 nm. The photodegradation rate significantly increased with decreasing wavelength and increasing the UV intensities. The activity of hydroxyl radicals was suppressed when methanol was used as the solvent instead of water. An increase in the photon effect was observed when the UV intensity was higher than $5.77{\times}10^{-5}$ einstein $L^{-1}min^{-1}$ at 254 nm, and lower than $1.56{\times}10^{-4}$ einstein $L^{-1}min^{-1}$ at 365 nm. The quantum yield efficiency for the photolysis of TCS was higher at 365 nm than at 254 nm among the above mentioned UV intensities. Dibenzodichloro-p-dioxin (DCDD) and dibenzo-p-dioxin were detected as intermediates at both UV intensities of $1.37{\times}10^{-4}$ and $1.56{\times}10^{-4}$ einstein $L^{-1}min^{-1}$ at 365 nm. Dichlorophenol and phenol were also detected in all cases. Based on our findings, we presented a possible mechanism of TCS photolysis.

The study on Installation Areas of Permeable Pavement for Stormwater Control (우수유출 저감을 위한 투수성 포장의 설치 면적에 관한 연구)

  • Jang, Young-su;Shin, Hyun-suk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.11
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    • pp.104-109
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    • 2017
  • The flooding and deterioration of water quality caused by urbanization and climate change are becoming more serious. In order to respond to this, studies on low impact development (LID) technology, which is designed to restore the hydrological system of the urban basin to its natural state, have been actively pursued all over the world, The announcement of the low carbon green growth law, hydrophilic area special law, etc., highlights the importance of technology such as the LID method. However, whereas various developments have been made in relation to the current LID element technology, there has been little research designed to verify its effectiveness. In this study, we analyzed the optimum spatial distribution of pitcher fire pitcher packing in parking lots using the K - LIDM model to verify the effectiveness of the low impact development (LID) method in the early stages. Using the eight package scenario and the three rain intensity scenarios, it was found that the lower 40% pitcher packaging results in an approximately 90% spill reduction effect, as in the case of the whole pitcher's package. The confirmation of these analyses and experimental verification is expected to ensure that the actual pitcher packaging will be used as a basis for arranging LID facilities such as urban planning and housing development in the future.

Cavitation Analysis on Ship Seawater Pump Using CFD (CFD를 이용한 선박용 해수펌프의 공동현상에 대한 분석)

  • Kim, Bu-Gi;Kim, Hong-Ryeol;Yang, Chang-Jo;Kim, Jun-Ho
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.23 no.4
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    • pp.400-406
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    • 2017
  • The model used in this study was reversed to analyze the cause of excessive damage that occurred inside the rotating system and pipe system of a centrifugal-type seawater pump on a ship. For this purpose, internal flow analysis on a cooling seawater pump was performed using CFD. As a result, the shape and boundary conditions of the target pump were set by reverse engineering, and pump efficiency at a design operating point of $125m^3/h$ was calculated as 85.3 % with a head of 32.0 m. The maximum efficiency point of the target pump was estimated to be 86.2 % at $150m^3/h$, but this differed from the actual operating point. At $112.5m^3/h$, which was the lowest flow point, flow was unstable due to the characteristics of the low flow point and analysis convergence was not good. The purpose of this study was to clarify the cause of ongoing cavitation in seawater pumps and piping systems in operation. Future research will be needed to clarify causes for pipe systems in the future by performing calculations for the total piping system of an inlet and outlet, in addition to measuring the flow rate of each branch pipe.

Dynamic analysis of slack moored spar platform with 5 MW wind turbine

  • Seebai, T.;Sundaravadivelu, R.
    • Ocean Systems Engineering
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    • v.1 no.4
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    • pp.285-296
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    • 2011
  • Spar platforms have several advantages for deploying wind turbines in offshore for depth beyond 120 m. The merit of spar platform is large range of topside payloads, favourable motions compared to other floating structures and minimum hull/deck interface. The main objective of this paper is to present the response analysis of the slack moored spar platform supporting 5MW wind turbine with bottom keel plates in regular and random waves, studied experimentally and numerically. A 1:100 scale model of the spar with sparD, sparCD and sparSD configuration was studied in the wave basin ($30{\times}30{\times}3m$) in Ocean engineering department in IIT Madras. In present study the effect of wind loading, blade dynamics and control, and tower elasticity are not considered. This paper presents the details of the studies carried out on a 16 m diameter and 100 m long spar buoy supporting a 90 m tall 5 MW wind turbine with 3600 kN weight of Nacelle and Rotor and 3500 kN weight of tower. The weight of the ballast and the draft of the spar are adjusted in such a way to keep the centre of gravity below the centre of buoyancy. The mooring lines are divided into four groups, each of which has four lines. The studies were carried out in regular and random waves. The operational significant wave height of 2.5 m and 10 s wave period and survival significant wave height of 6 m and 18 s wave period in 300 m water depth are considered. The wind speed corresponding to the operational wave height is about 22 knots and this wind speed is considered to be operating wind speed for turbines. The heave and surge accelerations at the top of spar platform were measured and are used for calculating the response. The geometric modeling of spar was carried out using Multisurf and this was directly exported to WAMIT for subsequent hydrodynamic and mooring system analysis. The numerical results were compared with experimental results and the comparison was found to be good. Parametric study was carried out to find out the effect of shape, size and spacing of keel plate and from the results obtained from present work ,it is recommended to use circular keel plate instead of square plate.

Study on Behaviour of Flood Wave-front Varied with Levee Breach Speed in Flat Inundation Area (평탄지형 제내지에서의 제방붕괴속도에 따른 범람홍수파 선단 거동에 관한 연구)

  • Yoon, Kwang Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.1
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    • pp.537-544
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    • 2017
  • An experimental study was carried out to investigate the characteristics of the propagation distance of a flood wave considering the levee failure speed in a flat inundation area. The Ritter solution for one dimensional flow was considered to formulate the experimental results and a representative form with coefficients of k and m, which consider the three dimensional flow characteristics, was applied. The experiments showed that the propagation velocity of the wave front in the inundation area was influenced by the levee breach speed as well as the initial water level, which is a significant variable representing the flood wave behavior. In addition, coefficients k and m are not constants, but variables that vary with levee breach speed. An empirical formula was also suggested using the experimental results in the form of the relationships between k and m. In this study, a large-scale experiment for flood inundation was carried out to examine the behavior of flooding in the inundated area and the relationships between the levee breach speed and wave-front propagation velocity were suggested based on the experimental results. These research results are expected to be used as the baseline data to draw a flow inundation map, establish an emergency action plan, and verify the two-dimensional numerical model.

Corni Fructus attenuates testosterone-induced benign prostatic hyperplasia by suppressing 5α-reductase and androgen receptor expression in rats

  • Hwangbo, Hyun;Kwon, Da He;Choi, Eun Ok;Kim, Min Yeong;Ahn, Kyu Im;Ji, Seon Yeong;Kim, Jong Sik;Kim, Kyung-Il;Park, No-Jin;Kim, Bum Hoi;Kim, Gi-Young;Hong, Su-Hyun;Park, Cheol;Jeong, Ji-Suk;Choi, Yung Hyun
    • Nutrition Research and Practice
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    • v.12 no.5
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    • pp.378-386
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    • 2018
  • BACKGROUND/OBJECTIVES: Benign prostatic hypertrophy (BPH) is a major cause of abnormal overgrowth of the prostate mainly in the elderly. Corni Fructus has been reported to be effective in the prevention and treatment of various diseases because of its strong antioxidant effect, but its efficacy against BPH is not yet known. This study was designed to evaluate the therapeutic efficacy of Corni Fructus water extract (CF) in testosterone-induced BPH rats. MATERIALS/METHODS: To induce BPH, rats were intraperitoneal injected with testosterone propionate (TP). Rats in the treatment group were orally administered with CF with TP injection, and finasteride, which is a selective inhibitor of $5{\alpha}$-reductase type 2, was used as a positive control. RESULTS: Our results showed that the increased prostate weight and histopathological changes in BPH model rats were suppressed by CF treatment. CF, similar to the finasteride-treated group, decreased the levels of testosterone and dihydrotestosterone by TP treatment in the serum, and it also reduced $5{\alpha}$-reductase expression and concentration in prostate tissue and serum, respectively. In addition, CF significantly blocked the expression of the androgen receptor (AR), AR co-activators, and proliferating cell nuclear antigen in BPH rats, and this blocking was associated with a decrease in prostate-specific antigen levels in serum and prostate tissue. CONCLUSIONS: These results suggest that CF may weaken the BPH status through the inactivation of at least $5{\alpha}$-reductase and AR activity and may be useful for the clinical treatment of BPH.

Re-reading Chuncheon G5 International Design Competition from a Viewpoint of Landscape Urbanism (랜드스케이프 어바니즘의 관점으로 본 춘천 G5 국제설계경기 출품작 분석)

  • Kim Ah-Yeon;Koh Mi-Jin;Oh Hyung-Seok
    • Journal of the Korean Institute of Landscape Architecture
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    • v.34 no.3 s.116
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    • pp.120-138
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    • 2006
  • A city evolves over time. It grows, transforms, and sometimes degrades. Chuncheon is at a turning point from a city souggling with regulations regarding clean water supply and a military encampment to a masterpiece city with a sustainable vision. The city is getting ready to restructure itself to become a world-famous culture and tourism complex expanding its physical boundary across the Camp Page site and absorbing Jungdo as a major tourist attraction. The landscape in the future blueprint of Chuncheon will play a great role in restructuring urban form. The regenerated in will have a new networked open space system as well as re-evaluated landscape resources. The hybrid theoretical practice called 'landscape urbanism' burgeoning in the fields between 'landscape architecture' and 'urbanism' can guide us in considering the terms of the relationship between a city and landscape when we design a future city Landscape urbanism is considered to be an effective framework by which we can diagnose the current status of a landscape in our contemporary urban design practice in Korea. This paper tries to provide a different perspective from the viewpoint of landscape urbanism to decipher the hidden implications of the social agreement on the role of landscape in urban structure by re-reading eight design proposals presented for the ChunCheon G5 international design competition based on the main principles of landscape urbanism. The G5 design competition is a great opportunity to test out new ideas on a city, demonstrating the relative values among various urban-design professional realms. First, this paper provides an overview of the main ideas of landscape urbanism based on the literature review and case studies. Second, framework categories are suggested in order to extract the explicit and implicit ideas on the landscape. Third, eight proposals are reviewed according to the suggested categories to situate the current landscape design of Korea within the mainstream of contemporary practice of landscape urbanism. Based on the review of eight proposals, the following diagnostic conclusions are made; first, the ideas of landscape urbanism have not been actively introduced in large-scaled urban landscape projects in Korea like Chuncheon G5. Second, it remains to be a big task for landscape professions to be able to participate in design consortiums on an equal footing. Third, In order to introduce and reify the ideas of landscape urbanism in Korea, it is inevitable and critical to test the ideas in both academic fields and professional practices to find the appropriately adjusted model of landscape urbanism.