• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1860-1864
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• 2006

본 연구는 강우시 발생되는 강우유출수와 합류식하수관거월류수에 의해 하천으로 유입되는 오염부하를 저감시키기 위한 공법으로, 고수부지 및 제방사면부와 둔치부를 형상화하여 pilot를 제작하였고, 연속적으로 시운전을 한 SRTS(Stormwater Runoff Treatment System)에 관한 것이다. SRT system 내부의 사면수처리부와 평면수처리부에는 다공성 콘크리트를 충진하였다. system 상부에는 식생을 조성하여 뿌리가 수면에 닿아 영양물질을 흡수하는 목적으로 사면수처리부와 평면수처리부에 각각 정육각형과 직사각형인 식생포트를 탈.부착이 가능하도록 고안하였다. 내부에서는 토양과 수처리조 사이에 연결관을 부착하였고, 모세관현상에 의해 토양이 수분을 흡수하도록 구성하였다. pilot plant는 유입부, 사면 수처리부, 평면 수처리부, 유출부로 나누었다. 유입부는 유입펌프와 V-notch로 구성하였고, 유입펌프는 2대를 설치하여 1시간 간격으로 연속적 유입으로 유량조절이 가능하도록 상호교대 운전을 하였다. 평면 수처리부$(W(1.0m){\times}(L(2.4m){\times}H(0.6m))$는 장방형의 접촉산화조로서 하부에 슬러지 침전 및 저류를 위한 hopper를 설치하여 슬러지의 원활한 수집 및 인발이 가능하도록 하였다. 유출부는 사각weir를 설치하였다. 강우유출수의 pH는 $7.27{\sim}7.92$이고, DO농도는 $7.12{\sim}7.88mg/l$로 관측되었다. 2차처리수의 pH는 평균7.4이고 DO농도는 최저 4.5 mg/l에서 최고 8.9 mg/l로 평균 6.8 mg/l로 관측되었다. 또한 강우유출수의 유입수의 T-N, T-P 농도는 각각 $17.5{\sim}22.5mg/l,\;8.9{\sim}11.4mg/l$의 범위이고, 2차 처리수의 유입수의 T-N, T-P 농도와 유사하였다.적인 방법론을 제시할 수 있을 것으로 사료된다.첨두홍수량을 저류하기 위해서 상대적으로 넓은 저류면적이 필요한 것으로 나타난다. 대등한 수위감소값의 홍수저감효과를 발휘하기 위해서 본 연구에서는 On-Line 저류지 면적은 Off-Line 저류지에 비 두배 이상이 필요한 것으로 보여졌다.들에 관한 정보는 종종 현장관측에서 조차 무시되는 경우가 많다. 이에 본 연구에서는 수질모형의 매개변수 중 특히 수리특성에 관련된 매개변수들이 수질에 미치는 영향을 파악하는 것을 목적으로 하고 있다. 이를 위해 적용된 수질모형은 QualKo를 사용하였으며, 대상 하천은 낙동강 본류 경남구간 시점 부근인 회천 합류 전부터 낙동강 본류 경남구간 종점 부근인 밀양강 합류 전까지의 경남 오염총량관리 기본계획 시 구축된 모형 매개변수를 바탕으로 분석을 수행하였다. 일차오차분석을 이용하여 수리매개변수와 수질매개변수의 수질항목별 상대적 기여도를 파악해 본 결과, 수리매개변수는 DO, BOD, 유기질소, 유기인 모든 항목에 일정 정도의 상대적 기여도를 가지고 있는 것을 알 수 있었다. 이로부터 수질 모형의 적용 시 수리 매개변수 또한 수질 매개변수의 추정 시와 같이 보다 세심한 주의를 기울여 추정할 필요가 있을 것으로 판단된다.변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였다. 이상의 행태적 측면과 투자성과측면의 실증결과를 통하여 한국주식시장에 있어서 시장수익률을 평균적으로 초과할 수 있는 거래전략은 존재하므로 이러한 전략을 개발 및 활용할 수 있으며, 특히, 한국주식시장에 적합한 거래전략은 반전거래전략이고, 이 전략의 유용성은 투자자가 설정한 투자기간보다 더욱 긴 분석기간의 주식가격정보에 의하여 최대한 발휘될 수 있음을 확인하

• The Korean Journal of Mycology
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• v.49 no.3
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• pp.337-349
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• 2021

This study aimed to isolate wild yeasts from water and soil sample of the Nonsan stream and Sapgyoho (lake) in Chungcheonnam-do, Korea, and to further characterize previously unrecorded wild yeast strains. In total, 102 strains, representing 55 different species of wild yeast were isolated from 95 samples collected from the Jangseoncheon and Ipchoncheon of Nonsan stream in Jellabuk-do and Chungcheonnam-do. Among these, 33 strains were isolated from alkalophilic yeast extract-peptone-dextrose (YPD) medium (pH 9.0), and 9 strains were isolated concurrently on general YPD medium (pH 6.5) and alkalophilic medium. Seventeen strains of Cryptococcus laurentii were predominantly isolated. Additionally, 65 strains, representing 27 different species of wild yeast were isolated from 58 samples obtained from Sapgyoho (lake). Among the 82 isolated wild yeast strains, 8 strains, including Candida fructus JSC 72-1(JSL-GGU 015), had not previously been recorded. All 8 previously unrecorded yeasts were oval in shape except C. fructus JSC72-1(JSL-GGU-015), and only the Filobasidium chernovii JSC39-1(JSL-GGU-013) strain formed spores. All strains except Pseudosydowia eucalypti JSC23-6(JSL-GGU-012) grew well in yeast extract-peptone-dextrose (YPD) and yeast extract-malt extract media and grew in vitamin-free medium. Four strains, including P.eucalypti JSC23-6(JSL-GGU-012) grew well in 15% NaCl-containing YPD medium. F.chernovii JSC39-1(JSL-GGU-013) and Sirobasidium intermedium JSC7-3(JSL-GGU-014) assimilated lactose, and five strains, including F. chernovii JSC39-1(JSL-GGU-013) also assimilated starch. All strains were resistant to 800 ppm of Ca, Cu, Li, and Mg ions.

• Journal of Animal Science and Technology
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• v.47 no.6
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• pp.985-1000
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• 2005

In vitro anaerobic incubations of timothy (Phleum pretense L.) forage with bovine rumen fluid were conducted at 39℃ for 0, 3, 6, 9, 24, and 36 h in three trials to examine the biohy- drogenation of linolenic (C18:3) and linoleic acids (C18:2) and their bypass from the rumen. The objectives of the first trial was to study the effect of growth stage (stem elongation, early heading, late heading, and early flowering) and N-fertilization (0 and 120 kg N ha－1) on in vitro biohydrogenation of C18:2 and C18:3. The hydrogenable fraction, the effective disappearance and the bypass of C18:2 and C18:3 were high in timothy harvested at stem elongation, and decr- ease linearly with maturity. The N-fertilization increased the hydrogenable fraction of C18:3, the effective disappearance and the bypass of C18:2 and C18:3. However, the rate of disappearance of C18:2 and C18:3 were not affected by maturity and N-fertilization (P>0.1). In trial 2, the effect of timothy conservation method on in vitro C18:2 and C18:3 biohydrogenation was determined. Silage had the highest effective disappearance of C18:2 and C18:3, and grass hay had lowest one. The amounts of C18:2 and C18:3 biohydrogenated were higher in haylage and silage than in grass hay. Comparative to haylage timothy, the bypass of C18:3 was higher in fresh grass, wilted grass and grass hay. The bypass of C18:2 was higher in fresh grass and silage in comparison to grass hay and haylage. In trial 3, the effects of formic acid and Lactobacillus plantarum inoculum addition to timothy haylage and silage on C18:2 and C18:3 disappearance and bypass were studied. Haylage and silage additives had no effect (P>0.1) on effective disappearance and bypass of C18:2 and C18:3. The addition of formic acid increased the rate of biohydrogenation of C18:3 in haylage and silage, but it decreased the hydrogenable fraction of C18:2 in silage. The results of these three incubation trials show that the hydrogenable fraction and the bypass of C18:2 and C18:3 in timothy decreased with maturity and increased with N-fertilization. Higher amount of C18:2 and C18:3 were biohydrogenated in haylage and silage than in grass hay, and C18:3 ruminal disappearance was higher in fresh grass, wilted grass and grass hay than in haylage.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.6
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• pp.906-914
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• 2009

The Korean Society of Animal Science (KSAS) was officially born on October 8, 1956 under the leadership of Professor Sang W. Yun of Seoul National University, Seoul, Korea a few years after the end of the Korean War. At that time, there were 0.9 million Korean native cattle, 1.3 million pigs and 8.9 million chickens in Korea. Per capita income for Korea (US$ 66) or China (US$ 59) was about 10% of Asian's average income (US$ 513) in 1956. Korea produced less than 0.2 million M/T of formula feed and consumed 6.1 kg/person/year of animal products. One could say that Korea was an example of an under-developed country in the world. Although the first issue of the Proceedings of the KSAS was published on October 28, 1958, regular quarterly journals of the KSAS were not published until March 1, 1969. Major activities other than publishing its journal were: holding an annual meeting and/or scientific forum at national or international level. The Asian-Australasian Association of Animal Production Societies (AAAP) was founded on September 1, 1980 at Kuala Lumpur, Malaysia with founding members from Australia, Indonesia, Japan, Korea, Malaysia, NZ, Philippines and Thailand. Thirteen AAAP Animal Science Congresses have been held in its 28 year history. Hosting countries were Malaysia (1980), Philippines (1982), Korea (1985), NZ (1987), Taiwan (1990), Thailand (1992), Indonesia (1994), Japan (1996), Australia (2000), India (2002), Malaysia (2004), Korea (2006) and Vietnam(2008). In 1988, significant progress of the AAAP was made by creating an official English journal of the AAAP entitled "Asian-Australasian Journal of Animal Sciences (AJAS)" under the initiative of the KSAS. This journal is now published monthly and distributed to more than 50 countries in the AAAP region and the world. It should be mentioned that the KSAS was able to successfully host the $3^{rd}$ AAAP Animal Science Congress in 1985 and the 12th in 2006, as well as the $8^{th}$ WCAP in 1998. During the last 50 years of KSAS history, per capita income of Korea increased to US$ 17,690 (268 fold), formula feed production increased to 15 million M/T (97 fold) and consumption of animal products increased to 105 kg/person/year (17 fold). Cattle, pig and chicken numbers also increased to 2.5 million (2.8 fold), 9 million (7.4 fold) and 119 million (13 fold). This trend was also found for China and Asia, even if the rate of growth was slightly lower than that of Korea. It is expected that a similar rate of growth in economics, animal numbers, formula feed production and animal protein intake will likely be achieved by other Asian countries in the $21^{st}$ century with somewhat lower rate of development than that of Korea.

• Korean Journal of Organic Agriculture
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• v.26 no.3
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• pp.381-391
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• 2018

This study was carried out to determine whether cage traps can be used to capture wild boars successfully, and to assess their response to different bait materials and the number of wild boars caught. Steel cage-traps ($4.0m{\times}1.5m{\times}1.2m$, $L{\times}W{\times}H$) were installed at two sites in Damyang County and at one site in Sunchang County, South Korea. To identify preferred bait-diet, baits were prepared with dry corn and fermented sour corn and placed in equal amounts at the sites close to wild boar pads at 200 m intervals. Before selecting trap locations where sufficient activity was observed, pre-baiting was undertaken and steel-framed traps were installed with gates open. Preference for bait materials was not clearly defined. After providing the bait for the first time, the number of days until wild boars ate all the food were counted. In the Damyang and Youngam areas, where hunting was allowed, total bait consumption took 6 to 12 days; in contrast, in the Sunchang area, where no hunting took place, total food consumption took only 5 days. In addition, after pre-baiting with the mixture of dry and sour corn for diet for about 8.7 days and then opening the trap gates for 3 more days, 13.7 days were necessary to catch 4.3 wild boars per trap. These results suggest that hunting intensity around trapping places was an important factor in determining the success of the traps.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.2
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• pp.141-146
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• 1999

This experiment was conducted to investigate the effects of application seasons and the level of cattle slurry on nitrate contents in soils of rye cultivation under climatic conditions of Korea. The main plots were appliaction seasons(100% application in spring, 100% application in autumn, 50% application in spring and autumnn after dividing cattle slurry into two equal parts) and subplots were the levels of cattle slurry-N application(0, 50, 100 and $200kgN\;ha^{-1}\;year^{-1}$). Cattle slurry was spred evenly over the soil surface in spring (end of March) and autumn(early of November). The experiment was done at Gongiam, Kwangju, Kyung-gi for 3 years, from 1994 to 1996. The results obtained are summarized as follows; 1. Nitrate content in soils was not influenced by application seasons of cattle slurry. 2. Nitrate content in soils increased as the level of cattle slurry application increased, and the average nitrate content became 3.6mg per liter. 3. Nitrate content in the soil depth from 0 to 20cm increased as the level of cattle slurry application increased, and the average nitrate content became 28.9mg per liter. However, nitrate content in the soil depth from 40 to 60cm was the lowest(7.5-8.3mg per liter).

• Korean Journal of Materials Research
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• v.15 no.6
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• pp.413-418
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• 2005

Perovskite $Pb(Ni_{1/3}Nb_{2/3})O_3-Pb(Zr,Ti)O_3[PNN-PZT]$ ceramics were synthesized by conventional ceramic processing technique. In order to modify piezoelectric properties for sensor application in this system, NiO addition was considered to provide $Ni^{+2}$ as an acceptor, which was known to occupy with B site in the structure. The effect of NiO addition up to $8\;mol\%$ on the following piezoelectric properties as well as sintering properties was investigated. When NiO added more than $1\;mol\%$, average grain size was decreased and second phase was found to form. Moreover, the second phase caused decrease in relative dielectric constant $(\varepsilon_{33}T/\varepsilon0)$, electro-mechanical coupling factor $(k_p)$, and piezoelectric charge constant $(d_{33})$, while increasing mechanical quality factor $(Q_m)$. When $1\;mol\%$ NiO was added, density, dielectric properties and piezoelectric properties were abruptly increased.

• Radiation Oncology Journal
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• v.22 no.3
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• pp.217-224
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• 2004

Purpose: It is well known that the radiosensitivity of tumor cells can be significantly reduced under hypoxic conditions. Hypoxia-inducible factor-1 $\alpha$ (HIF-1 $\alpha$) plays a pivotal role in the essential adaptive responses to hypoxia. Therefore this study investigated the relationship between HIF-1 $\alpha$ expression and radiosensitivity. M Mouse hepatoma cell line hepafcic7 and HIF-1 $\beta$-deficient mutant cell line hepa1C4 were used to analyze the role of HIF-1 a. on radiosensitivity. These cells were exposed for 6 h to desferrioxamine (DFX) before radiation. HIF-1$\alpha$. expression was examined by Western blot. Apoptosis was assessed by DNA fragmentation, propidium iodide staining, and apoptotic cell death detection ELISA kit. Radiation sensitivity was determined using MTT assay. The radiobioiogical parameters, surviving fractions at 2 Gy and 8 Gy, and mean inactivation dose (MID) from the linear-quadratic model were used to assess radiation sensitivity in the statistical analyses. Results: The expression of HIF-1 $\alpha$. was Increased, whereas apoptosis was decreased, by radiation In the presence of DFX In hepal cl c7, but not In hepal C4. The radlosensitivity of hepal C4 cells was not significantly affected by DFX treatment. The radiosensitivlty of hepal cl c7 cells was significantly decreased in the presence of DFX Conclusion: The expression of HIF-1 w by hypoxia-mimic agent DFX reduced apoptosls and radiosensitlvity in mouse hepatoma cell line hepafclc7. These results suggested that HIF-1 u could be Induced by irradiation in hypoxic ceils of tumor masses, and that this mlght Increase radioresistance in hypoxic cells.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.62-62
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• 2018

Pt is still considered as one of the most active electrocatalysts for ORR in alkaline fuel cells. However, the high cost and scarcity of Pt hamper the widespread commercialization of fuel cells. As a strong candidate for the replacement of Pt catalyst, silver (Ag) has been extensively studied due to its high activity, abundance, and low cost. Ag is more stable than Pt in the pH range of 8~14 as the equilibrium potential of Ag/Ag+ being ${\approx}200mV$ higher than that of Pt/PtO. However, Ag is the overall catalytic activity of Ag for oxygen reduction reaction(ORR) is still not comparable to Pt catalyst since the surface Ag atoms are approximately 10 times less active than Pt atoms. Therefore, further enhancement in the ORR activity of Ag catalysts is necessary to be competitive with current cutting-edge Pt-based catalysts. We demonstrate the architectural design of Ag catalysts, synthesized using plasma discharge in liquid phase, for enhanced ORR kinetics in alkaline media. An attractive feature of this work is that the plasma status controlled via electric-field could form the Ag nanowires or dendrites without any chemical agents. The plasma reactor was made of a Teflon vessel with an inner diameter of 80 mm and a height of 80 mm, where a pair of tungsten(W) electrodes with a diameter of 2 mm was placed horizontally. The stock solutions were made by dissolving the 5-mM AgNO3 in DI water. For the synthesis of Agnanowires, the electricfield of 3.6kVcm-1 in a 200-ml AgNO3 aqueous solution was applied across the electrodes using a bipolar pulsed power supply(Kurita, Seisakusyo Co. Ltd). The repetition rate and pulse width were fixed at 30kHz and 2.0 us, respectively. The plasma discharge was carried out for a fixed reaction time of 60 min. In case of Ag nanodendrites, the electric field of 32kVcm-1 in a 200-ml AgNO3 aqueous solution was applied and other conditions were identical to the plasma discharge in water in terms of electrode configuration, repetition rate and discharge time. Using SEM and STEM, morphology of Ag nanowires and dendrites were investigated. With 3.6 kV/cm, Ag nanowire was obtained, while Ag dendrite was constructed with 32 kV/cm. The average diameter and legth of Ag nanowireses were 50 nm and 3.5 um, and thoes values of Ag dendrites were 40 nm and 3.0 um. As a results of XPS analysis, the surface defects in the Ag nanowires facilitated O2 incorporation into the surface region via the interaction between the oxygen and the electron cloud of the adjacent Ag atoms. The catalytic activity of Ag for oxygen reduction reaction(ORR) showed that the catalytic ORR activity of Ag nanowires are much better than Ag nanodendrites, and electron transfer number of Ag nanowires is similar to that of Pt (${\approx}4$).

• Journal of the Korean Vacuum Society
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• v.19 no.4
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• pp.243-248
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• 2010

Sonic nozzles have been a standard device for measurement of steady state gas flow, as recommended in ISO 9300. This paper introduces two sonic nozzles of diameter ${\Phi}$ 0.03 mm and ${\Phi}$ 0.2 mm precisely machined according to ISO 9300. The constant volume flow meter(CVFM), readily set up in the Vacuum center of KRISS. was used to calibrate the discharge coefficients of both nozzles. The calibration results were shown to determine them within the 3% expanded measurement uncertainty. Calibrated sonic nozzles were found to be applicable for precision measurement of steady state gas flow in the vacuum process in the ranges of 0.6~1,800 cc/min. Those flow conditions are equivalent to the fine gas flow with Reynolds numbers of 26~12,100. Those encouraging results confirm that calibrated sonic nozzles enable precision measurement of extremely low gas flow encountered very often in th vacuum processes. Both calibrated sonic nozzles are proven to provide the precision measurement of the volume flow rate of the dry vacuum pump within one percent difference in reference to CVFM. Calibrated sonic nozzles are applied to a new 'in-situ and in-field' equipment designed to measure the volume flow rate of vacuum pumps in the semiconductor and flat display processes. Furthermore, they can provide other applications to flow control devices in vacuum, such as MFC, etc.