• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.6
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• pp.481-487
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• 2009

This paper proposes a regulation method of DC line voltage for urban transit system fluctuated during the acceleration or deceleration by using supercapacitor. Supercapacitor is modelled electrically under the assumption of three different time constants of RC circuits with variable capacitances depending on the voltage. And its parameters are determined by the experimental measurements. The energy storage system using supercapacitors is installed based on this model, and the proposed model is tested through the simulations and experiments, and the controller for charging and discharging is designed. Finally, it is tested at Kyoungsan test site for the urban light rail road system and the energy saving effect is evaluated economically.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.49-49
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• 2017

최근 극한 홍수의 발생에 따른 내수배제 불량으로 인한 도시지역의 침수로 매년 많은 인명과 재산상의 손실이 크게 증가하고 있으며, 홍수피해 저감 및 복구대책으로 많은 국비가 지원되고 있으나 아직까지 예방보다는 복구비에 치중하고 있는 실정이다. 이에 본 연구에서는 도시지역에 시간 당 강우의 영향력에 대한 평가를 실시하여 상습적으로 일어나는 내수재해를 방지하고 자한다. 이를 위하여 서울시 저지대를 기준으로 상습침수 배수구역을 선택하여 1차원 SWMM모형을 구축하였다. 이때, 가장 중요한 인자 중 하나인 강우의 시간분포는 도시별 유역 규모 및 유출특성, 강우강도 특성 등에 따라 상이한 결과를 보일 여지가 다분하여 실제 침수를 일으킨 강우와 유사한 분포를 찾기 매우 어려운 실정이며, 이를 반영하기 위하여 Huff분포 모든 분위를 사용하여 SWMM 도시침수 해석을 실시하였다. 실시한 결과 맨홀의 월류량을 2차원 해석 입력자료로 사용하였으며, 2차원 해석 결과를 분위별 침수범위를 GIS를 이용하여 중첩시켜 상습 침수구역을 제시하였다. 본 연구 결과를 바탕으로 강우강도의 조건에 따라서 관로를 통하여 월류되는 시작 지점 및 그 지점을 통하여 맨홀에서의 월류량을 대략적 알 수 있었다. 또한, 능동적이며 준 실시간적인 대피지도와 우회도로설정 의사결정에 도움이 될 것으로 판단된다.

• Korean Journal of Environment and Ecology
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• v.27 no.3
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• pp.271-279
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• 2013

The species of Corydalis cornupetala Y.H.Kim et J.H.Jeong Which is belong to the Corydaliaceae is only distributed at the Gyaejeong Forest in Gyeongsan. As one of the spring ephemeral plants, this species has limited growing period. The present study is on site characteristics and vegetation structure in the wild habitats of Corydalis cornupetala Y.H.Kim et J.H.Jeong and offers basic information on habitat conservation including recovery plan. The soil texture is silty loam and soil acidity is ranged as pH 5.4~5.9. The electric conductivity was 0.22-0.50 ds/m and soil organic content is ranged as 7.61~15.78 %. Fifty nine vascular plants were identified from 5 quadrats. According to the two way cluster analysis applied by the PC-ORD, the community was classified as Acer ginnala, Vicia amoena and Stellaria aquatica. The habitat of Corydalis cornupetala Y.H.Kim et J.H.Jeong was determined by the dissimilarity indices rather than the species number of appearance. Species diversity was 1.26, and dominance and evenness were found to be 0.08 and 0.92, respectively.

• Korean Journal of Animal Reproduction
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• v.19 no.2
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• pp.147-152
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• 1995

The purpose of this study was to examine the estrus synchronization and superovulation of pigs with hormone treatments. Three different kinds of procedures for synchronization and superovulation were used as follow: I) gilts in natural estrus behavior (control): 2) gilts synchronized with 20mg altrenogest for 9 days regardless of the estrus cycle; 3) gilts received PG600 (400IU PMSG + 200 IU hCG) in 15 day of the estrus cycle; and then gilts administrated with PMSG (1,500 IU) and hCG (750 IU) after altrenogest and PG600 treatment for superovulation. Estrus was checked daily with a boar, in estrus synchronization, the intervals from hormone treatment to estrus were different between PG600 (43/47) and altrenogest (13/53) within 6 days. The percentage of animals displaying a estrus response were not different by hormone treatments. The average number of corpora lutea (C.L) and ovulated embryos were similar between PG600 25.4${\pm}$13.1, 19.0$\pm$12.8 and altrenogest 25.5${\pm}$0.7, 15.0${\pm}$4.2, respectively, but was increased (P<0.05) by hormone treatment compared to that 12.9${\pm}$1.8, 12.7${\pm}$3.9 in the control. The number of normal embryos after ovulation was higher in the control than hormone treatment. Therefore, these results suggest that altrenogest and PG600 treatment could be a valuable for cut down the labour and cost by synchronization.

• Korean Journal of Ecology and Environment
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• v.36 no.1 s.102
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• pp.48-56
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• 2003

This study was evaluated about the seasonal variations of ecosystem in Nammae Reservoir based on the interrelation of physico-chemical characteristics, nutrients, chlorophyll a, b, c and standing crops of phytoplanktons. The amounts of chlorophyll a, b, c were respectively maximum (295 mg/, 9.5mg/l and 48mg/l) at station 1 in June and the standing crop of phytoplanktons was the highest ($1.7{\time}10^5$ cells/1) at stations 3 in July. The range of temperature was $7{\sim}37.4^{\circ}C$. The maxium of pH was $9.9{\sim}10.1$ at all stations in August, the minimum was 7 in September. SS was maximum (308 mg/1) at station 1 in June, while it was minimum (4 mg/l) at the same station in November. The maximal COD and DOC were 33 mg/1 and 16 mg/1 respectively at station 1 in June. As for phytoplanktons, Microcystis aeruginosa, blue-green alga in July${\sim}$August, Scenedesmus acutus, green alga in March${\sim}$May and November${\sim}$January and Cyclotella orientalis, Diatoms in October were dominant species. The amounts of P and Si were generally high in summer, they were low in autumn and winter. Nammae Reservoir assessed by trophic state index was eutrophicated and overtrophicated. These results indicated that Nammae Reservoir was faced with heavy water pollution. As preceding management for the basin of the Reservoir, it will have to be continually studied for an ecosystem reservation.

• Korean Journal of Microbiology
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• v.38 no.1
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• pp.31-37
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• 2002

For elucidating the correlation between the eubacterial community structure and environmental parameters in Nammae Reservoir located in Kyungsan, Kyungbuk, the bacterial community structure and their structure affecting environmental parameters were analyzed using Fluorescent In Situ Hybridization (FISH) monthly over year. $\alpha$ . $\beta$ . $\gamma$-subclasses of Proteobacteria and Cytophaga-Flavobacterium (CF) group known as dominant bacterial group in freshwater were detected in 3 stations over year. The ratio of each subclass to total bacteria was determined; $\alpha$.$\beta$ . $\gamma$-subclasses and CF group varied in the range of 4.0~29.2%, 1.7~25.8%, 1.8~12.8%, 4.9~36.3%, respectively and there was no substantial differences between stations. In terms of the correlation between each group specific bacteria and environmental parameters such as temperature, SS, pH, DOC, NH$_4$-N, NO$_3$-N, PO$_4$-P, standing crops of algae, the results were as follows: 1) total bacterial numbers correlated positively with temperature, SS and DOC, 2) Eubacteria positively with DOC and Chl-$\alpha$, 3)${\gamma}$-subclass positively with DOC, and 4) CF group positively with standing crops of chlorophyceae, 5) whereas $\beta$-subclass bacteria correlated negatively with standing crop of cyanobacteria and that of total algae.

• Microbiology and Biotechnology Letters
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• v.40 no.3
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• pp.190-196
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• 2012

In this study, a total of more than 1,000 bacteria, including 739 species of aerobic bacteria, 80 species of urease producing bacteria and 303 species of photosynthetic bacteria, were isolated from red-pepper field soils located in the Gyeongsan Province of the Republic of Korea. Amongst these, 158 species of aerobic bacteria, 70 species of urease producing bacteria and 228 species of photosynthetic bacteria were found to be auxin producing soil bacteria through quantification analysis with the Salkowski test. The latter groupings were then tested for antifungal activities to ${\beta}$-Glucanase and siderophore using CMC congo red agar and CAS blue agar media. In addition, the selected strains were examined for antifungal activity against various phytopathogenic fungi on PDN agar media. Six strains; BCB14, BCB17, C10, HA46, HA143, and HJ5, were noted for their ability to both produce auxin and act as antifungal substances. 16S rDNA sequence comparison analyses of these six strains identified them as Bacillus subtilis BCB14, B. methylotrophicus BCB17, B. methylotrophicus C10, B. sonorensis HA46, B. subtilis HA143, and B. safensis HJ5.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.521-524
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• 2008

The purpose of this study is to identify the character and condition of Cr in the clinker and thereby contribute to the research for reduction in utilizing Cr in the cement manufacturing process. The concentration of chromium by cement particle size and the distribution of chromium by clinker mineral were measured. Next, correlation was considered between chromium and the soluble components in cement. As a result, in the range that cement particles were 20${\mu}$m or less, highest soluble hexavalent chromium was found. When the concentration of chromium was measured through mineral separation, belite and the interstitial phase were higher in chromium than in alite. soluble hexavalent chromium was contained in domestic cement less than 20ppm, and its conversion ratio was somewhat high as 10 to 40% or so.

• Journal of the Korean association of regional geographers
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• v.22 no.1
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• pp.25-35
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• 2016

This paper is to classify subregions of Yeongnam region, to realize their core area, and to provide the basis on studying inherent cultural characteristics in Yeongnam region. To do so, I made a overlay human factors of administrative district and dialect with physical factors of drainage basin and climate area. The limit of subregion is the range of possessing environmental factors similar to provincial center. The parcels possessing a equivalent combination of environmental factors are 27, the size of parcel is various from one-city/county to six-city/county. These parcels are classified to six subregions(Andong, Sangju, Kyeongju, Daegu, Kimhae, Jinju). The boundary of subregion is high mountains and large river which are obstacle to communication between subregions, and in case of little obstacle exists transitional zone.

• Journal of the korean veterinary medical association
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• v.46 no.9
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• pp.816-821
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• 2010

일반적으로 알려져 있는 소에 있어서의 제각은 화학적인 소락제, 송아지 제각기 (tube calf dehorner), 전기인두, 톱 및 선거(線鋸; wire saw) 등을 이용하고 있으나, 제각 처치시 소에 많은 스트레스를 주고 있는 실정에 있다. 2001년도에 일본의 요우카이치시(四日市) 소재 냉동 및 냉장창고업을 하는 일신냉장고(주)에 근무하는 직원이 현내의 비육농장에서 제각하는 것을 보고, 생산자나 소비자로부터 이야기를 나누던 중, 점차적으로 소 사육농장에서 다두사육화가 되면서 우군 무리중에서 순위싸움으로 인해 외상을 입거나, 경쟁에 밀린 소는 사료를 제대로 먹지 못하여 스트레스를 받는 다는 것에 착안하여, 끝이 뾰쪽한 뿔에 복싱 글러브(boxing glove)와 같은 커버를 장착하면 제각을 하지 않고 소 본래의 자연체형을 유지한 체로 안심, 안전, 위험방지가 가능한 소의 뿔 커버를 연구개발하게 되었다. 최초로 제작된 소의 뿔 커버는 고무 특유의 수축작용을 이용해서 소의 뿔에 장착하였으나, 소의 큰 압력에 눌려 하루도 못가 각상피(角上皮)와 같이 탈락하였으며, 그 후 약 3년간은 실패를 거듭한 끝에 4년째인 2005년 봄에 의외의 장소에서 힌트를 얻었는 데, 귀가시 가족중 우연히 이가 빠졌는 것을 보고, 소의 각돌기(角突起)의 각첨부(角尖部)에 고정하는 방법을 생각하게 되었다. 연구를 시작하면서부터 NOSAI 수의사들, JA 동일본조합사료 수의사, 전농축산 서비스 등의 도움을 받았으며, 이후 오리온기업육성기술개발지원사업에 채택되어 4년여간의 연구를 한 끝에 약 30초의 부착시간이 걸리는 1회성의 영구적인 소의 뿔 커버를 특허개발(2005년)하여 2008년도부터 판매하기 시작하여 거세 화우, 교잡종 화우암소, 화우 암소 등에 일본 전역에서 보급되어 시술되고 있다. 최근 수개월전에 제가 아는 지인이 일본서 뿔 커버 2두분을 직접 구입하여 왔는 바, 직접 한우 경산우 암소 2두에 극히 간편하고 쉽게 시술하였기에 소개하여 도움을 주고 저 한다.