• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.328-330
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• 2005

Most of the water level controllers of the actual plant are PID controllers. But they have limitations in appling for tracking the set point and getting rid of disturbances, so there are some defects to apply in the actual ground even though many research works represented the resolution to solve it. In this paper, we design a fuzzy logic system (FLS) for controlling the steam generator water level in nuclear power plants. Some computer simulations reveal similar performance with the conventional PID controller.

• 생약학회지
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• 제37권3호
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• pp.169-176
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• 2006

This study was designed to observe the effects of Korean mistletoe(Viscum album L. var. coloratum Ohwi) hot-water extract administration on the improvement on the lipid components, apolipoprotein and blood pressure level in spontaneously hypertensive rats (SHR, Wistar strain, male) fed the experimental diets for 33 days. Concentrations of total cholesterol, triglyceride (TG), LDL-cholesterol, free cholesterol and atheroscieotic index in serum were significantly lower in the Korean mistletoe extract administration group [group KM(Korean mistletoe 10.0 g% hot-water extract)] than those in the control group. In the ratio of HDL-cholesterol concentration Korean mistletoe 10.0% hot-water extract administration group were higher percentage than in the control group. However, concentrations of total cholesterol and TG in liver and brain were significantly lower in the group KM than those in the control group. But the components of apolipoprotein (Apo) A-I and Apo A-II in serum were significantly higher in the KM group than in the control group. However, components of Apo C-II, Apo C-III, Apo E and ratio of Apo B to Apo A-I in serum were fairly reduced in the group KM than in the control group. The levels of systolic and diastolic blood pressure were significantly lower in KM cup than control group. From these results, Korean mistletoe hot-water extract administration were effective on the improvement of the lipid components, coronary heart disease and hypertension in spontaneously hypertensive rats. And particularly, Korean mistletoe extract administration were more effective as a therapeutic regimen for the control of blood pressure in hypertension.

• Journal of Forest and Environmental Science
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• 제30권1호
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• pp.76-84
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• 2014

This study was performed to monitor the effects of water level change on changes of landscape, vegetation community, and species diversity of riparian forest. Hantan river dam, study area, has been constructed in the area of Chansoo-myeon, Pocheon-si and Yeoncheon-eup, Yeoncheon-gun, Gyeonggi-do, which is a dam for flood control only in flooding season. Landscape changes were notable after the construction of coffer dam, and the changes were caused by water level increase in areas of riparian forests which consisted of mainly withered willow as a dominant species in the flooding season. It changed vegetation communities of riparian forest from Phragmites japonica and Salix koreensis to Phragmites japonica. Species diversity index was lowest in 2010 when the coffer dam was constructed and showed an increasing trend later. Thus, this study is well in agreement with a previous report that plants of the genus Salix wither by muddy water during flooding and also suggests, controlling water level of river and prediction of water level change's effects should be considered when any facilities are planned.

• 생명과학회지
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• 제10권4호
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• pp.326-332
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• 2000

In order to investigate the possibility of functional property improvement of meat products, four kinds of pork patties were prepared with water 10% as control, mugwort extract 10%, pine needle extract 10% and fatsia leaf extract 10%, respectively. In case of control moisture content was higher, but crude fat was lower, compared to patties treated with plant extracts. Crude ash content of pine needle extract treatment showed higher level than that of other patties. pH range of patties revealed to 5.92∼5.978. In raw patties Hunter's L-and a-value of control were higher than those of plant extract treatment, and a-value of raw patties showed higher level than that of cooked. Yield, water holding capacity, salt soluble protein extractability and gel strength among patties did not show significant differences. In control patty, fat retention was lower compared to other plant extract treatments, but water soluble protein extractability was higher compared to pine needle. Values such as hardness, springiness, cohesiveness, gumminess and chewiness were not significantly different among the patties. In sensory scores such as aroma, juiciness and palatability, significant differences were not observed among cooked patties, but texture score was higher in the order pine needle, mugwort, fatsia leaf and control.

• 공업화학
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• 제26권4호
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• pp.421-426
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• 2015

미세조류 Arthrospira platensis는 단백질 함량이 높고, 불포화 지방산 등을 다량함유하고 있어 건강보조식품 및 다양한 분야에서 활용되고 있다. 또한 phycocyanin, myxoxanthophyll, zeaxanthin 등의 색소를 함유하고 있어서 항산화물질, 식품 첨가물로도 이용되고 있다. 나노기포 수소수는 수소 기체를 나노기포 상태로 물속에 주입하여 포화용해도 이상으로 용해시킨 것이다. 이런 나노기포 수소수는 항산화능이 높고, 항암효과가 있는 것으로 알려져 있다. Arthrospira platensis를 일반 증류수 배지와 수소수로 제조한 배지에서 배양한 후 특성을 확인하였다. 배양 결과, 세포 성장 및 광합성으로 인한 색소인 chlorophyll과 carotenoid의 함량은 수소수 배지에서 배양하였을 경우 대조군에 비해 15% 정도 증가한 것으로 나타난다. 그리고 phycocyanin 역시 7% 정도 증가하였다. 하지만, 지질함량은 수소수 배지 배양과 일반 배지 배양 간에 큰 차이가 없는 것을 확인하였다. 항산화물질의 함량을 확인하기 위해 flavonoid 및 polyphenol의 함량을 측정하였다. Flavonoid는 수소수 배지에서 배양하였을 경우 대조군에 비해 70% 이상 증가함을 보이고 있다. 하지만 polyphenol은 대조군과 유사한 함량을 보이고 있다.

• 한국가시화정보학회지
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• 제12권1호
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• pp.30-34
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• 2014

Bluff bodies under the external periodic force vibrate at their own natural or forced frequency. Rectangular bodies or similar structures such as high-rise towers and apartments, and recently a well-cited application - offshore floating bodies, usually needs to reduce these vibrations for stability and the mode control. Therefore, this study is aiming to reduce or control the vibration of a structure by a passive control method, i.e., TLCD (Tuned Liquid Column Damper). Controlling a moving body with a TLCD based on a variety of the orifice shape has been preliminary studied. In order to get a proper control, an optimized study is made on the design of the orifice shape, which has internal plates with the holes. The results show the force acting on the body due to the periodic movement highly depends on the number of holes on the plate and the height of the water level. Therefore, the optimum shape of the orifice and the height of the water level should be confirmed by a series of experiments.

• 한국물환경학회지
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• 제26권6호
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• pp.903-909
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• 2010

The purpose of this study was evaluated on the applicability of Load Duration Curve Method (LDC Method) using HSPF watershed model and sampling data for efficient TMDLs in Korea. The LDC Method was used for assessment pollutant characteristics in watershed and water quality variation in each water flow level. Load Duration Curve is applied for judge the level of impaired water-body and can be estimated the impaired level by pollutant, such as BOD, T-N, and T-P in this study depending on variation of stream flow. As a result, BOD, T-P was usually exceed the standard value at low flow and dry hydrologic period. Improvement of effluent concentration from WWTP and riparian buffer protection zone are effective to improve the water quality. T-N showed the worst condition at mid-range hydrologic period and moist hydrologic period. Therefore, soil erosion control program and BMPs for non-point source pollution control is effective for recovery the water quality, which can be useful method for management of water quality in the plan of recovery water quality spontaneously. Applicability of LDC Method was evaluated in the Nakbon A watershed. However, we need to consider more detailed and accumulated data set such as accurate GIS data and detail pollution data, and WWTP discharge water quality data for accurate evaluation of watershed. Overall, The LDC Method is adequate for evaluation of watersheds characteristics, and its application is recommended for watershed management and TMDL Implementation.

• 한국콘텐츠학회논문지
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• 제6권6호
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• pp.16-25
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• 2006

운영되고 있는 대부분의 저수조는 사람의 오감에 의해 관리되고 있다. 이에 인적 물적 자원은 낭비되고 있다. 본 연구에서는 인적 자원의 낭비를 줄이고, 저수조를 온라인 실시간으로 관리하기 위하여 저수조 무선 통합 관리 시스템을 제안한다. 저수조 수위 센서가 저수위 감지시 저수조 콘트롤에서 무선을 통해 데이터를 무선 콘트롤로 보내어 펌프를 가동한다. 이때 저수조에서 일어나는 각종 데이터를 라인전송 모뎀으로 송신한다. 라인전송 모뎀에서 수신된 데이터는 각 시간 단위로 로그를 기록한 후 데이터베이스에 저장된다. 저장된 데이터를 기반으로 펌프동작, 펌프고장, 수위, 태양전지고장, 약품, 전화회선을 감지한 후 실시간으로 결과를 가시화한다. 저수조 무선 통합 관리 시스템을 개발하여 시스템의 논리적 타당성과 유효성을 검증하기 위해 실험적인 적용을 시도하고자 한다.

• Nuclear Engineering and Technology
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• 제36권1호
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• pp.73-82
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• 2004

The deaerator of a power plant is one of feedwater heaters in the secondary system, and it is located above the feedwater pumps. The feedwater pumps take the water from the deaerator storage tank, and the net positive suction head(NSPH) should always be ensured. To secure the sufficient NPSH, the deaerator tank is equipped with the level control system of which level sensors are critical items. And it is necessary to ascertain the sensor state on-line. For this, a model-based fault detection and diagnosis(FDD) is introduced in this study. The dynamic control model is formulated from the relation of input-output flow rates and liquid-level of the deaerator storage tank. Then an adaptive state estimator is designed for the fault detection and diagnosis of sensors. The performance and effectiveness of the proposed FDD scheme are evaluated by applying the operation data of Yonggwang Units 3 & 4.

• 한국습지학회지
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• 제13권2호
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• pp.275-289
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• 2011

파주시 민간인 통제구역 내에 존재하는 둠벙의 수문 지형학적 분류를 위해 둠벙의 특성을 조사하였다. 물을 논농사에 이용하는 둠벙을 조사한 결과 모두 85개가 존재하였다. 조사된 둠벙을 수문학적 특성 중 계절별 수위변화 정도에 따라 나누면, 계절에 따라 수위가 크게 변하는 둠벙은 52개, 계절에 무관하게 항상 일정한 둠벙이 33개였다. 수원에 따라 분류하면 강수 의존 지표수인 경우가 12개, 지하수와 지표수인 경우가 29개, 지하수만인 경우가 44개였다. 4개는 산지에 33개는 평지에 48개는 계곡에 위치하였다. 40개는 논과 물의 교환이 일어나지 않았으며, 45개는 수위가 변함에 따라 교환이 일어났다. 멸종위기종 또는 특산종이 서식하는 둠벙은 모두 26개였으며, 주로 수위가 일정하며, 지하수를 수원으로 가지는 둠벙에 해당하였다. 이와 같은 특징을 바탕으로 둠벙을 샘통형, 물흐름형, 괸물샘통형, 괸물형으로 나누는 방법을 새로이 제시하였다. 이와 같이 둠벙의 유형을 제시함으로써 이들을 체계적으로 조사 정리하여, 둠벙을 유형적으로 관리하는 데 도움을 주고자 하였다.