• Journal of Korea Water Resources Association
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• v.53 no.6
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• pp.427-436
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• 2020

It is uncertain how global climate change will influence future drought characteristics over the Korean peninsula. This study aims to project the future droughts using climate change and land use change scenarios over the Korean peninsula with the land surface modeling system, i.e., Weather Research and Forecasting Model Hydrological modeling system (WRF-Hydro). The Representative Concentration Pathways (RCPs) 2.6 and 8.5 are used as future climate scenarios and the Shared Socio-economic Pathways (SSPs), specifically SSP2, is adopted for the land use scenario. The using Threshold Level Method (TLM), we identify future hydrological and ecological drought events with runoff and Net Primary Productivity (NPP), respectively, and assess drought characteristics of durations and intensities in different scenarios. Results show that the duration of drought is longer over RCP2.6-SSP2 for near future (2031-2050) and RCP8.5-SSP2 (2080-2099) for the far future for hydrological drought. On the other hand, RCP2.6-SSP2 for the far future and RCP8.5-SSP2 for the near future show longer duration for ecological drought. In addition, the drought intensities in both hydrological and ecological drought show different characteristics with the drought duration. The intensity of the hydrological droughts was greatly affected by threshold level methods and RCP2.6-SSP2 for far future shows the severest intensity. However, for ecological drought, the difference of the intensity among the threshold level is not significant and RCP2.6-SSP2 for near future and RCP2.6-SSP2 for near future show the severest intensity. This study suggests a possible future drought characteristics is in the Korea peninsula using combined climate and land use changes, which will help the community to understand and manage the future drought risks.

• Proceedings of The Korean Society of Health Promotion Conference
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• 2005.09a
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• pp.91-119
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• 2005

오타와 헌장에 따르면 건강증진은 건강형평성을 성취하는 것이다. 건강격차를 감소시키고, 모든 사람들이 건강잠재력을 달성할 수 있도록 동등한 기회와 자원이 제공되어야 한다. 또한 각 개인들은 자신의 건강에 대한 결정요인들에 대한 통제능력을 가져야 한다. 미국의 조기사망은 40%가 행동양식에 의하여, 30%가 유전적인 문제로, 15%가 사회적 환경에 의하여, 10%는 의료적 치료의 부족으로, 그리고 5%는 환경위해 물질에 대한 노출로 발생한다. 건강불평등을 발설시키는 사회적 요인으로는 경제적 요인을 들 수 있다. 이러한 요인으로 야기되는 건강불평등의 문제를 해결하여 건강형평성을 달성하기 위해서는 절대적 목표들과 평등관련 목표들이 모두 필요하다. 건강형평성은 인구집단의 건강과 함께 향상되는 것으로 나은 건강상태에 있는 사람들의 건강을 악화시키면서 건강형평성을 달성하는 것은 아니다. 각자의 관심이 형평성을 어떻게 규정하는가에 영향을 미친다. 혜택을 받은 사람들은 성과/투입의 정의를 선호하며, 소외계층은 똑같은 성과 또는 요구에 기반한 정의를 선호한다. Healthy People 2010은 미국의 국가적 예방체계를 의미하며, 가장 중요하며 예방 가능한 건강위협들을 파악하고 이러한 위협들을 감소하기 위한 목적들이 설정되어 있다. 궁극적인 목적은 건강한 삶의 질적인 면과 양적인 측면을 향상시키는 것이며, 건강불평등을 제거하는 것이다. 그러나 미국이 유럽의 국가들에 비해서 사회 프로그램에 대한 투자가 적은 이유는 재분배는 소수인종만을 위한 것이라는 믿음과, 우리는 개방되고 공정한 사회에 살고 있기 때문에 가난하다는 것은 가난한 사람들 자신들의 잘못으로 인한 것이라는 믿음 그리고 재분배를 방지하는 정치체계 때문이다. 국가기관인 CDC의 예방연구센터(Prevention Research Centers)는 지역사회 파트너들과 함께 건강증진, 질병예방, 그리고 질병과 상해로 인한 합병증을 관리하게 위한 효과적인 예방 전략을 개발하고 있다. 예방연구센터의 프로그램들은 지역사회 기반 참여연구와 소외된 계층에 중점을 두며, 다학제 간 접근방법을 활용하고, 교육기관, 공공보건기관 그리고 지역사회의 파트너들 간의 네트웍을 형성을 통한 협력관계를 강조하고 있다. 지역사회 위원회가 구성되어 있으며, 또한 근거중심 프로그램을 개발하고 있다. 이들은 건강 결정요인에 관한 연구, 형성적 연구, 개입 프로그램 및 프로그램의 확산에 관한 연구를 진행한다. UC Berkeley의 가족/지역사회 보건센터(Center for Family & Community Health)는 1993년에 설립되었다. 사업의 대상이 되는 주요 지역사회는 한국교민사회이며, 한국교민사회 자문위원회(Korean Community Advisory Board, KCAB)가 구성되어 있다. 1993년부터 2003년까지는 'Health is Strength' 사업이 시범연구사업으로 진행되었는데, 그 내용은 유방암과 자궁경부암 검진 프로그램이었다. 2003년부터 2009년까지 진행될 'Quitting is Winning'이라는 두 번째 시범연구사업은 남성들의 금연에 중점을 둔 사업이다. 'Health is Strength'는 아시아 보건서비스 및 한국교민사회 자문위원회가 함께 협력하여 진행된 사업으로, 주요 목표는 18세 이상 여성의 자궁암 조기 검진(Pap test)과 자가 유방검진 실천을 증가시키는 것이며, 50세 이상여성의 유방 임상검사와 유방 X선촬영 비율을 증가시키는 것이었다. 한 지역의 카운티에 거주하는 한국 여성들은 4년간의 개입프로그램의 대상이 되었으며, 이들을 대상으로 횡단적인 전화조사를 3번(사전, 중간, 사후)실시하였다. 개입 프로그램은 교회에서 워크샵 개최, Tell-A-Friend Form 작성하기, 포스터 및 책자 발행, 신문광고 등과 함께 자궁암 조기 검진(Pap test)과 유방 X선 촬영권을 무료로 제공하는 것으로 구성되었다. 'Quitting is Winning'은 지역사회 기반 참여 연구모형으로 한국교민사회 자문위원회는 흡연을 1순위의 사업으로 선정하였고, 근거에 기반한 금연 프로그램에 대한 연구들을 검토하여, 기존의 보편적 방법이 아닌 인터넷을 활용하는 프로그램을 진행하는 것으로 결정되었다. 이는 무작위 임상실험으로 연구대상으로 미국에 거주하는 한국인 남성흡연자 2300명을 모집하였다. 이들의 1/2은 실험군인 인터넷 프로그램 집단에, 또 다른 1/2은 대조군인 인쇄책자 집단에 무작위 할당되었다. 12개월 동안 11번의 진단이 인터넷을 통하여 진행되었으며, 참여와 참여유지에 대한 금전적인 보상이 제공되었다.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.167.2-168
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• 2003

현대 사회는 서구적인 식생활의 변화로 인해 조리가 간편하고 조리 시간이 짧은 즉석식품과 영양 기호식품을 동시에 충족시켜주는 음식에 대한 소비가 늘고 있는 실정이다. 또한 최근 미곡의 공급량에 비해서 소비량이 해마다 감소하여 재고미의 증가를 볼 때, 쌀의 새로운 이용방법 모색이 절실히 요망된다. 따라서 쌀의 소비촉진과 현대사회의 소비형태를 접목시켜서 쇠고기와 야채를 이용한 즉석쌀죽을 개발하고자 하였다. 쇠고기, 야채 및 쌀가루를 이용한 soup mix의 최적 배합비를 설정하기 위하여 제조조건에 따라 다르게 제조한 쇠고기 야채 쌀죽의 이화학적 및 관능적 특성에 미치는 변화를 조사하였다. 이때 야채의 배합비에 따른 이화학적 및 관능적 특성을 모니터링 하고자 반응표면분석법 (response surface methodology, RSM)을 이용하였다. 요인변수(Xn)를 쌀의 양에 대한 버섯의 비율 (X$_1$), 당근의 비율 (X$_2$), 대파의 비율 (X$_3$)로 하여 중심합성계획에 따라 17실험구로 구분하여 조리실험을 실시하였고, 반응변수(Yn)는 soup mix를 이용하여 제조한 쇠고기 야채 쌀죽의 이화학적 특성인 색도의 L＊값 (Y$_1$), a＊값 (Y$_2$), b＊값 (Y$_3$), 점도(Y$_4$), 퍼짐성 (Y$_{5}$), 고형분 함량(Y$_{6}$), PH (Y$_{7}$)으로 하였으며 관능적 특성인 색 (Y$_{8}$), 향 (Y$_{9}$), 점성 (Y$_{10}$), 맛 (Y$_{11}$), 전체적인 기호도 (Y$_{12}$)를 종속변수로 하여 회귀분석에 이용하였다. 회귀분석에 의한 모델식의 예측에는 SAS (statistical analysis system)program을 사용하였으며, 3차원 반응표면 분석법으로 해석하였다. 야채의 배합비에 따라 제조한 쇠고기 야채 쌀죽의 물리적 특성인 색도의 L＊, a＊, b＊ 값에 대한 반응표면 회귀식의 $R^2$은 각각 0.6098(p＞ 0.05), 0.8803 (p ＜0.05), 0.6781(p＞ 0.05)로서 b값에 있어서 그 유의성이 5%수준에서 인정되어 b값에 미치는 영향이 크다는 것을 알 수 있었다. L＊값은 63-68사이로, a＊값은 0.13에서 -0.89사이를 b＊값은 2-5값 사이에서 변화하여 제조한 죽의 색이 옅은 황색임을 알 수 있었다. 고형분 함량, 퍼짐성과 pH에 대한 $R^2$은 각각 0.4280, 0.5433과 0.2406임을 볼 때 버섯, 당근, 대파의 비율에 따라 제조한 쇠고기 야채 쌀죽의 고형분 함량, 퍼짐성과 pH는 설정된 범위내에서 그 유의성이 인정되지 않아 큰 영향을 미치지 않음을 알 수 있었다. 관능검사 결과, 색과 향에 대한 반응표면 회귀식의 $R^2$은 각각0.6000과 0.7825이고 P-value는 각각 0.4290과 0.0942로서 5% 수준에서 유의한 상관성이 없음을 확인할 수 있었다. 맛과 점성에 대한 $R^2$은 0.8717과 0.8068이고 P-value는 각각 0.0195 (p ＜0.05)와 0.0612로서 야채의 배합비에 따라 맛에 있어서 유의확률 5%수준에서 그 유의성이 인정되었으며, 전체적인 기호도에 대한 유의성은 $R^2$이 0.8463이고 P-value는 0.0344 (p ＜0.05)임을 볼 때, 설정된 범위내에서 야채의 배합비에 따라 제조한 쇠고기 야채 쌀죽의 맛과 기호도에 큰 영향을 미치는 것을 알 수 있었다. 그리고 최대 임계점이 버섯의 첨가량은 0.99%, 당근의 첨가량은 0.97%, 대파의 첨가량은 0.59%에서 최적 반응표면을 나타내었다. 이상의 결과로 볼 때, 야채의 배합비에 따른 맛과 전체적인 기호도에 있어서 그 유의성이 5%수준에서 모두 유의한 상관관계를 보였으며, soup mix 제조시 쌀가루 양에 대한 야채의 최적 배합비는 버섯, 당근, 대파에 있어서 각각 0.99, 0.97과 0.59%임을 알 수 있었다.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.80-80
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• 2003

${\beta}$-lapachone(${\beta}$-Lap), a natural o-naphthoquinone, presents in the bark of the Lapacho tree. ${\beta}$-Lap is cytotoxic against a variety of human cancer cells and it potentiates the anti-tumor effect of Taxol. In addition, ${\beta}$-Lap has been reported to radiosensitize cancer cells by inhibiting the repair of radiation-induced DNA damage.In the present study, we investigated the cytotoxicity of ${\beta}$-Lap against RKO human colorectal cancer cells as well as the combined effect of ${\beta}$-LaP and ionizing radiation. An incubation of RKO cells with 5 ${\mu}$M of ${\beta}$-Lap for 4 h killed almost 90％ of the clonogenic cells. An incubation of RKO cells with 5 ${\mu}$M of ${\beta}$-Lap for 4 h or longer also caused massive apoptosis. Unlike other cytotoxic agents, ${\beta}$-Lap did not increase the expression of p53 and p21 and it suppressed the NFkB expression. The expression of Caspase 9 and 3 was minimally altered by ${\beta}$-Lap. Radiation and ${\beta}$-Lap acted synergistically in inducing clonogenic cell death and apoptosis in RKO cells when ${\beta}$-Lap treatment was applied after but not before the radiation exposure of the cells. Interestingly, a 4 h treatment with 5 ${\mu}$M of ${\beta}$-Lap starting 5 h after irradiation was as effective as that starting immediately after irradiation. The mechanisms of ${\beta}$-Lap-induced cell killing is controversial but a recent hypothesis is that ${\beta}$-Lap is activated by NAD(P)H: quinone-onidoreductase (NQO1) in the cells followed by an elevation of cytosolic Ca$\^$2+/ level and activation of proteases leading to apoptosis. It has been reported that NQO1 level in cells is markedly up-regulated for longer than 10 h after irradiation. Indeed, using immunological staining of NQO1, we observed a significant elevation of NQO1 expression in RKO cells 5h after 2-4 Gy irradiation. Such a prolonged elevation of NQO1 level after irradiation may be the reasons why the ${\beta}$-Lap treatment applied S h after irradiation was as effective as that applied immediately after irradiation in killing the cells. In view of the fact that the repair of radiation-induced damage is usually completed within 1-2 h after irradiation, it is highly likely that the ${\beta}$-Lap treahment applied 5 h after irradiation could not inhibit the repair of radiation-induced damage. For in vivo study, RKO cells were injected S.C. into the hind-leg of Nu/Nu mice, and allowed to grow to 130 mm3 tumor. The mice were i.p. injected with ${\beta}$-lapachone or saline 2 h after irradiation of tumors with 10 Gy of X-rays. The radiation induced growth delay was increased by 2.4 $\mu\textrm{g}$/g of ${\beta}$-lapachone. Taken together, we may conclude that the synergistic interaction of radiation and ${\beta}$-Lap in killing cancer cells is not due to radiosensitization by ${\beta}$-Lap but to an enhancement of ${\beta}$-Lap cytotoxicity by radiation through an upregulation of NQO1. The fact that NQO1 is elevated in tumors and that radiation causes prolonged increase of the NQO1 expression may be exploited to preferentially kill tumor cells using ${\beta}$-Lap in combination with radiotherapy.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.37-37
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• 2003

We have shown the $Ca^{2+}$-activated chloride current is present in cardiac myocyte in rabbit pulmonary vein (Kim et al., 2002). This current amplitude was increased as [N $a^{+}$]$_{i}$ was increased and we suggested this chloride current may be involve in the spontaneous action potential frequency change. Since this current is activated by the increase of intracellular $Ca^{2+}$, we would like to test what is the inducer of the increase of [C $a^{2+}$]$_{i}$ between a L-type $Ca^{2+}$-current or a reverse mode of N $a^{+}$-C $a^{2+}$ exchange current. White rabbit (1.5 kg) was used and anesthetized with Ketamin (100 mg/kg). Pulmonary vein (PV) was isolated and sleeve area between left atrium and PV was dissected. Using collagenase (Worthington 0.7 mg/cc), single cardiac myocytes were isolated. In the presence of 15 mM of N $a^{＋}$, three steps of voltage pulses were applied (holding potential : -40 ㎷, -80 ㎷ for 50 msec, 30 ㎷ for 5 msec, 10 ㎷ steps from -70 ㎷ to 60 ㎷). The inward and outward tail current was activated after brief 5 msec prepulse. The outward tail current was blocked by the removal of extracellular chloride substituted by glucuronic acid or by a chloride channel blocker, 5 mM 9-AC. But the inward tail current was still remained even though the amplitude was decreased. The reversal potentials were changed to the direction of the change of chloride equilibrium potential ( $E_{Cl}$ ) but the shift of equilibrium potential was not enough to match to the theoretical equilibrium potential shift. In the presence of L-type $Ca^{2+}$ channel blocker, nifedipine 1 uM, inward tail currents were greatly reduced but the outward current tail currents were still remained. In the presence of N $a^{+}$-C $a^{2+}$ exchange current blocker, 10 uM KB-R7943, the inward and outward tail currents were blocked almost completely. We tried to test the $Ca^{2+}$sensitivity of the chloride current with various [C $a^{2+}$]$_{i}$ in pipette solution from 100 nM to 1 uM but we failed to activate $Ca^{2＋}$-activated chloride currents even though the cell became contracted in the presence of 1 uM $Ca^{2+}$. From these results, we could conclude that the increase of [C $a^{2+}$]$_{i}$ to activate the outward $Ca^{2+}$-activated chloride current was mainly induced by the activation of the reverse mode of N $a^{+}$-C $a^{2+}$ exchanger, But for the increase of [C $a^{2+}$]$_{i}$ to activate the inward tail current, L-type $Ca^{2+}$ current may be the major provoking current. Since the cytosolic increase of [C $a^{2+}$]$_{i}$ through pipette solution have failed to activate $Ca^{2+}$-activated chloride current, this chloride current may have very low $Ca^{2+}$ sensitivity or a comparmental increase $Ca^{2+}$ such as in subsarcolemmal space may activate the chloride current. Since there are several reports and models that the increase of $Ca^{2+}$ in subsarcolemmal space would be over several to tens of uM, both possibility may be valid together.uM, both possibility may be valid together.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.12
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• pp.715-732
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• 2009

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2008. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends in thermal and fluid engineering have been surveyed in the categories of general fluid flow, fluid machinery and piping, new and renewable energy, and fire. Well-developed CFD technologies were widely applied in developing facilities and their systems. New research topics include fire, fuel cell, and solar energy. Research was mainly focused on flow distribution and optimization in the fields of fluid machinery and piping. Topics related to the development of fans and compressors had been popular, but were no longer investigated widely. Research papers on micro heat exchangers using nanofluids and micro pumps were also not presented during this period. There were some studies on thermal reliability and performance in the fields of new and renewable energy. Numerical simulations of smoke ventilation and the spread of fire were the main topics in the field of fire. (2) Research works on heat transfer presented in 2008 have been reviewed in the categories of heat transfer characteristics, industrial heat exchangers, and ground heat exchangers. Research on heat transfer characteristics included thermal transport in cryogenic vessels, dish solar collectors, radiative thermal reflectors, variable conductance heat pipes, and flow condensation and evaporation of refrigerants. In the area of industrial heat exchangers, examined are research on micro-channel plate heat exchangers, liquid cooled cold plates, fin-tube heat exchangers, and frost behavior of heat exchanger fins. Measurements on ground thermal conductivity and on the thermal diffusion characteristics of ground heat exchangers were reported. (3) In the field of refrigeration, many studies were presented on simultaneous heating and cooling heat pump systems. Switching between various operation modes and optimizing the refrigerant charge were considered in this research. Studies of heat pump systems using unutilized energy sources such as sewage water and river water were reported. Evaporative cooling was studied both theoretically and experimentally as a potential alternative to the conventional methods. (4) Research papers on building facilities have been reviewed and divided into studies on heat and cold sources, air conditioning and air cleaning, ventilation, automatic control of heat sources with piping systems, and sound reduction in hydraulic turbine dynamo rooms. In particular, considered were efficient and effective uses of energy resulting in reduced environmental pollution and operating costs. (5) In the field of building environments, many studies focused on health and comfort. Ventilation. system performance was considered to be important in improving indoor air conditions. Due to high oil prices, various tests were planned to examine building energy consumption and to cut life cycle costs.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.13-13
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• 2018

The anti-inflammatory (INF) compounds (1-15) were isolated from Agrimonia pilosa Ledeb. (APL) by activity-guided isolation technique. The isolated compounds (1-15) were identified as quercetin-7-O-rhanmoside (1), apigenin-7-O-glycoside (2), kaempferol-7-O-glycoside (3), apigenin-7-O-[6"-(butyl)-glycoside] (4), querceitn (5), kaempferol (6), apigenin (7), apigenin-7-O-[6"-(pentyl)-glycoside] (8), agrimonolide (9), agrimonolide-6-O-glucoside (10), desmethylagrimonolide (11), desmethylagrimonolide-6-O-glucoside (12), luteolin (13), vitexin (14) and isovitexin (15). Flavonoids, compound 2, 3, 11, and 14-15 have been found in APL for the first time. Furthermore, two novel flavone derivatives, compound 4 and 8, have been isolated inceptively in plant. In the no cytotoxicity concentration ranges of $0-20{\mu}M$, nitric oxide (NO) production level of 1-15 was estimated in LPS-treated Raw 264.7 macrophage cells. The flavone aglycones, 7 (apigenin, $IC_{50}=3.69{\pm}0.34{\mu}M$), 13 (luteolin, $IC_{50}=4.62{\pm}0.43{\mu}M$), 6 (kaempferol, $IC_{50}=14.43{\pm}0.23{\mu}M$) and 5 (quercetin, $IC_{50}=19.50{\pm}1.71{\mu}M$), exhibited excellent NO inhibitory (NOI) activity in dose-dependent manner. In the structure activity relationship (SAR) study of apigenin-derivatives (APD), apigenin; Api, apigenin-7-O-glucoside; Api-G, apignenin-7-O-[6"-(butyl)-glycoside]; Api-BG and apignenin-7-O-[6"-(pentyl)-glycoside]; Api-P, from APL on INF activity was investigated. The INF mediators level such as NO, INF-cytokines, NF-KB proteins, iNOS and COX-2 were sharply increased in Raw 264.7 cells by LPS. When pretreatment with APD in INF induced macrophages, NOI activity of Api was most effective than other APD with $IC_{50}$ values of $3.69{\pm}0.77{\mu}M$. And the NOI activity was declined in the following order: Api-BG ($IC_{50}=8.91{\pm}1.18{\mu}M$), Api-PG ($IC_{50}=13.52{\pm}0.85{\mu}M$) and API-G ($IC_{50}=17.30{\pm}0.66{\mu}M$). The NOI activity of two novel compounds, Api-PG and Api-BG were lower than their aglycone; Api, but more effective than Api-G (NOI: Api-PG and Api-BG). And their suppression ability on INF cytokines such as $TNF-{\alpha}$, $IL-1{\beta}$ and IL-6 mRNA showed the similar tendency. Therefore, the anti-INF mechanism study of Api-PG and Api-BG on nuclear factor-kappa B ($NF-{\kappa}B$) pathway, representative INF mechanism, was investigated and Api was used as positive control. Api-BF was more effectively prevent the than phosphorylation of $pI{\kappa}B$ kinase (p-IKK) and p65 than Api-PG in Raw 264.7 cells. In contrast, Api-PG and Api-BG were not reduced the phosphorylation of inhibitor of kappa B alpha ($I{\kappa}B{\alpha}$). Moreover, pretreatment with Api-PG and Api-BG, dose-dependently inhibited LPS-induced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) mRNAs and proteins in macrophage cells, and their expression were correlated with their NOI activity. Therefore, APL can be utilized to health promote agent associated with their AIN metabolites.

• Journal of Korea Water Resources Association
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• v.47 no.5
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• pp.459-468
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• 2014

Groyne to control the direction and velocity of flow in rivers is generally installed for the purpose of protecting riverbanks or embankments from erosion caused by running water. In particular, as interest in river restoration and natural river improvement increases, groynes are proposed as a key hydraulic structure for local flow control and riparian habitat establishment. Groynes are installed mainly in groups rather than as individual structures. In case of groynes installed as a group, flow around the groynes change according to spacing in between the groynes. Therefore, groyne spacing is regarded as the most important factor in groyne design. This study aimed at examining changes of flows around and within the area of groynes that take place according to the spacing of groynes installed in order to propose the optimal spacing for upward groynes. To examine flow characteristics around groynes, this study looked at flows in main flow area and recirculation flow area separately. In main flow area, it examined the impact of flow velocity increasing as a result of conveyance reduction that is exerted on river bed stability in relation to changes in the maximum flow velocity according to installation spacing. As a factor causing impacts on scouring and sedimentation within the area of groynes, recirculation flow in the groyne area can lead problems concerning flow within the area and stability of embankment. As for recirculation area, an analysis was conducted on the scale of rotational flow and the flow around embankment that exerts impacts on stability of the embankment. In addition, a comparative analysis was carried with reference to changes of the central point of rotational flow that occur within the area of groynes. As a result of compositely examining the results, the appropriate installation spacing is proposed as min. four times-max. six times considering a decrease in flow velocity according to the installation of upward groynes, river bed stability and stability of embankments against counterflow within the area of groynes.

• Journal of Korea Water Resources Association
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• v.46 no.4
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• pp.401-412
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• 2013

Water footprint of a product and service is the volume of freshwater used to produce the product, measured in the life cycle or over the full supply chain. Since water footprint assessment helps us to understand how human activities and products relate to water scarcity and pollution, it can contribute to seek a sustainable way of water use in the consumption perspective. For the introduction of WFP scheme, it is indispensable to construct water inventory/accounting for the assessment, but there is no database in Korea to cover all industry sectors. Therefore, the aim of the study is to develop water footprint inventory within a nation at 403 industrial sectors using Input-Output Analysis. Water uses in the agricultural sector account for 79% of total water, and industrial sector have higher indirect water at most sectors, which is accounting for 82%. Most of the crop water is consumptive and direct water except rice. The greatest water use in the agricultural sectors is in rice paddy followed by aquaculture and fruit production, but the greatest water use intensity was not in the rice. The greatest water use intensity was 103,263 $m^3$/million KRW for other inedible crop production, which was attributed to the low economic value of the product with great water consumption in the cultivation. The next was timber tract followed by iron ores, raw timber, aquaculture, water supply and miscellaneous cereals like corn and other edible crops in terms of total water use intensity. In holistic view, water management considering indirect water in the industrial sector, i.e. supply chain management in the whole life cycle, is important to increase water use efficiency, since more than 56% of total water was indirect water by humanity. It is expected that the water use intensity data can be used for a water inventory to estimate water footprint of a product for the introduction of water footprint scheme in Korea.

• Journal of Korea Water Resources Association
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• v.46 no.6
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• pp.597-611
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• 2013

This paper presents the methodology for construction of time-area curve via the width function and thereby rational estimation of time of concentration and storage coefficient of Clark model within the framework of method of moments. To this end time-area curve is built by rescaling the grid-based width function under the assumption of pure translation and then the analytical expressions for two parameters of Clark model are proposed in terms of method of moments. The methodology in this study based on the analytical expressions mentioned before is compared with both (1) the traditional optimization method of Clark model provided by HEC-1 in which the symmetric time-area curve is used and the difference between observed and simulated hydrographs is minimized (2) and the same optimization method but replacing time-area curve with rescaled width function in respect of peak discharge and time to peak of simulated direct runoff hydrographs and their efficiency coefficient relative to the observed ones. The following points are worth of emphasizing: (1) The optimization method by HEC-1 with rescaled width function among others results in the parameters well reflecting the observed runoff hydrograph with respect to peak discharge coordinates and coefficient of efficiency; (2) For the better application of Clark model it is recommended to use the time-area curve capable of accounting for irregular drainage structure of a river basin such as rescaled width function instead of symmetric time-area curve by HEC-1; (3) Moment-based methodology with rescaled width function developed in this study also gives rise to satisfactory simulation results in terms of peak discharge coordinates and coefficient of efficiency. Especially the mean velocities estimated from this method, characterizing the translation effect of time-area curve, are well consistent with the field surveying results for the points of interest in this study; (4) It is confirmed that the moment-based methodology could be an effective tool for quantitative assessment of translation and storage effects of natural river basin; (5) The runoff hydrographs simulated by the moment-based methodology tend to be more right skewed relative to the observed ones and have lower peaks. It is inferred that this is due to consideration of only one mean velocity in the parameter estimation. Further research is required to combine the hydrodynamic heterogeneity between hillslope and channel network into the construction of time-area curve.