검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 19

        1.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The objective of this study was to determine the changes in content of polyphenolics, flavonoids, amino acids, especially γ-aminobutyric acid (GABA), and the antioxidant activities in the methanol extracts of four different pigmented rice seeds (white, black, red, and green color) at different germination stages, dry seeds (DS), imbibed seeds (IS), and germinated seeds for 1 (GS1), 2 (GS2) and 3 days (GS3). Total phenolics content at 1000 mg/kg extract was highest in black rice, ranging from 208.3 to 257.3 mg/kg, and followed by red rice 144.7 to 185.7 mg/kg, brown rice 151.3 to 194.2 mg/kg and green rice 125.7 to 160.7 mg/kg (lowest). Total flavonoid level had same tendency to total phenolics among colored rices with significant differences, showing highest amounts (45.2 to 56.8 mg/kg) in black rice and lowest (18.8 to 23.0 mg/kg) in green rice. Total phenolics and total flavonoids levels in black and brown seeds were highest when soaked, and in red rice when nonsoaked, and in green rice when germinated for 1 day. These results showed that content of physiologically- active substances were differ depending on seed coat color, soaking or germinating degree. Content in total amino acids during germination was ranged from 136.5 to 232.0 mg/kg in green rice (highest), and 98.9 to 176.0 mg/kg in red rice (lowest). Total content of amino acids and GABA level in all seed colors were high in order of GS3 > GS1 > IS > DS. The antioxidant activity of the methanol extracts from all the seed colors concentration-dependently increased. DPPH free radical scavenging activity at 2,000 mg/kg was highest in black rice by 83.0 to 87.7%, and lowest in green rice by 44.3 to 65.7%.
        4,000원
        2.
        2007.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The aim of this study was to evaluate the effects of orvus es paste(OEP) on the sperm characteristics during freezing in boar semen. Semen quality was evaluated the motility, membrane integrity, mitochondria function, acrosome status, viability and abnormality. Boar semen were frozen until 5℃ for 2 hours using cell freezer and making the straws, and then freezing by lowing the straws into styrofoam box on the 8cm above the LN2 and plunged into LN2 for cryopreservation. In different concentration of OEP (0, 0.25, 0.5 and 1.0%) into cryo-extender, sperm motility, membrane integrity, acrosome status, viability and mitochondria function were significantly higher in 0.5% OEP than those of any other groups, but sperm abnormality were highest in 1.0% OEP group among all treatment groups (P<0.05). In the relationships of the evaluation methods for sperm viability, CBB vs membrane integrity, CBB vs HO/PI and CBB vs mitocondria function were positively correlated (0.67~0.92). Among the evaluation methods, CBB vs membrane integrity, CBB vs HO/PI and CBB vs mitocondria function were significantly correlated (P<0.001). These results of this study indicate that supplementation of 0.5% OEP in boar semen cryo-extender can improve the semen quality.
        4,000원
        3.
        2005.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        이 연구는 글루코만난과 유청칼슘의 혼합물이 1%-Cholesterol을 식이한 후 혈청콜레스테롤에 미치는 영향과 70%-Sucrose를 식이한 후 혈당에 미치는 영향을 알아보았다. 1%-Cholesterol을 식이한 쥐를 일반식이군(ND)과 비교하였으며, 고콜레스테롤식이군(HCD)에 글루코만난식이군(HCDG)과 글루코만난과 유청칼슘군식이군(HCDGW)으로 나누어 관찰하였다. 또한 70%-Sucrose를 식이한 쥐를 일반식이군(ND)과 비교하였으며, 고혈당식이군(HGD)에 글루코만난식이군(HGDG)과 글루코만난과 유청칼슘군식이군(HGDGW)으로 나누어 관찰하였다. 이를 비교 조사한 결과를 요약하면 다음과 같다. 1. 혈청콜레스테롤수치는 HCD> HCDG> HCDGW> ND의 순서로 감소하였다. 2. HCD의 혈청콜레스테롤증가량에 비하여 HCDG는 약 23.84% HCDGW는 약 42.38% 감소하였다. 3. 혈당수치는 HGD >HGDG> HGDGW> ND의 순서로 감소하였다. 4. HGD의 혈당증가량에 비하여 HGDG는 약 6.63% HGDGW는 약 63.14% 감소하였다.
        3,000원
        4.
        2001.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In the present study, the effect of Ni content on densification and grain growth in Ni doped W compacts was investigated by using the dilatometric analysis. The Ni-doped W compacts with various amount of Ni activator from 0.02 to 0.4 wt% were sintered in hydrogen atmosphere up to 140. As the amount of Ni and heating rates, the Ni-doped W compacts show a greatly different dilatometric behavior during the sintering. The sintered specimen was densified over 98% of theoretical density by adding only 0.06 wt% Wi in sub-micron W powder and the appropriate heating rate. It was also observed that the microstructure development strongly depended on the change of the Ni amount. In addition, it was found that the critical content of Ni showing large grain growth in microstructure was below 0.1 wt%.
        4,000원
        6.
        1997.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        An experiment of alum sludge application was carried out on a mountainous site, to know its effect on the growth of forage sorghum hybrid, Pioneer 93 1 (Sorghum bicolor x S. bicolor). When alum sludge with 80% water content was applied at the level of 133
        4,000원
        7.
        2018.10 서비스 종료(열람 제한)
        Background : Cirsium setidens is a perennial wild herb that belongs to the Asteraceae family. It grows in the mountainous region of Gangwon-do in Korea and is also called gondre. The bioconversion technology applied in this study has the same meaning as biosynthesis, biocatalyst, etc., and refers to a technique for producing desired products from precursors using enzymatic functions of microorganisms. Therefore, useful microorganisms having immunological activity were selected and Cirsium setidens fermentation products were prepared by applying bioconversion technology. And fermented product extracts were prepared to consider as a good sources of natural immune enhancement and functional food ingredients. Methods and Results : Lactobacillus fermentum, Lactobacillus plantarum, Saccharomyces cerevisiae, Weissella cibaria, and Lactobacillus plantarum were used as isolates from traditional foods. The fermentation product was set to a condition that the inherent physical properties did not change and did not generate a unique odor during fermentation. Cirsium setidens was fermented at 37℃ for 24 hours. And the fermented material was sterilized at 9 0℃ for 1 hour and then dried at 70℃ and pulverized. The contents of pectolinarin and pectolinarigenin, which are non - glycosides, were analyzed before and after fermentation using HPLC. Also NO production was measured in RAW264.7 cells after extract treatment at various concentrations using Griess reagent kit . The content of pectolinarin was increased in fermented Crisium setidens before fermentation, but the content of pectolinarigenin was increased after fermentation. In addition, the water extract of the fermented material accelerated the NO production compared to the pre - fermented material. Conclusion : As a result, relatively high immunostimulating effect were observed in dried Crisium setidens after fermentation, and it was confirmed that it could be a ingredient material for health functional food.
        9.
        2005.06 KCI 등재 서비스 종료(열람 제한)
        컨테이너 크레인의 제어방법에 관한 기존 연구는 피제어 변수의 최종목표치의 오차를 최소화하는 목적함수를 사용하여 제어계산을 하였기 때문에 계산에서 얻어진 입력은 실제 운전에 적합하지 않은 과도한 변화를 가지게 되었다. 본 연구에서는 컨테이너 크레인의 비선형 모델을 사용하여 4차 Chevyshev 함수로 근사한 제어입력을 계산하는 새로운 제어계산 방법을 제안하였다. 제어 목적식은 편차의 절대치의 합을 최소화하도록 구성하였고 최적화 계산에는 심플렉스 알고리듬을 활용하였다. 본 제안의 제어방법으로 계산된 제어 입력과 출력을 기존의 제어방식으로 계산된 결과와 비교하여 본 제안의 제어방식의 결과가 기존 제어방식에 비해 안정된 컨테이너 크레인 운전성능을 보였다.
        10.
        2004.12 KCI 등재 서비스 종료(열람 제한)
        본 연구에서는 사행하는 자연하천에 유입된 오염물질의 2차원 확산 특성을 모의하기 위하여 2차원 수심적분 모형인 RMA2와 RMA4를 사용하였다. 먼저 2차원 동수역학적인 모형인 RMA2를 사용하여 흐름장을 모의한 후 이 결과를 2차원 수질모형인 RMA4에 입력하여 농도장을 모의하였다. 수치모형을 S자형 사행수로에서 측정한 흐름 및 추적자 농도자료를 이용하여 검증한 결과, RMA4 모형은 최대유속선이 만곡의 내측에 치우쳐 나타나는 현상을 잘 모의하고 있었
        11.
        2004.08 KCI 등재 서비스 종료(열람 제한)
        해조류의 증식에 가장 큰 영향을 주는 것은 증식에 필요한 영양소와 적절한 수온 등 성장환경을 적절하게 유지시킬 필요가 있으나 해조류의 종류가 매우 다양하여 이들 각각에 개별적으로 대처하는 것이 매우 어렵다. 그러므로 본 연구에서는 실제의 미생물이 서식하고 있는 원수를 이용하여 적절한 온도를 유지시켜 미생물의 증식을 촉진시키고 이러한 미생물의 개체수를 측정하는 센서를 개발하였다. 이 센서를 이용하면 해조류의 양이 갑자기 증가하는 초기상황을 찾아낼 수 있으므로 해조류의 급격한 증식을 미리 예측할 수 있다.
        12.
        2003.10 KCI 등재 서비스 종료(열람 제한)
        본 연구에서는 사류 및 부압이 발생하는 자유수면을 가진 댐 상류 및 여수로에서 물의 흐름의 동수역학적인 거동을 파악하기 위하여 수치모형을 적용하였다. 댐 건설시, 댐 상류에서의 유동을 알아보기 위하여 2차원 수치모형인 RMA2를 이용하였고, 접근부에서의 3차원적 흐름과 여수로, 방류관 등에서의 흐름분포를 평가하기 위하여 3차원 CFD 프로그램인 FLUENT를 사용하였다. 수치모의에서는 지형 및 구조물에 관한 세부인자들이 수치모형을 구성하는 데 사용되었다
        13.
        2002.12 KCI 등재 서비스 종료(열람 제한)
        해수의 염도와 온도를 현장에서 측정할 수 있는 침적식 온라인 굴절계를 제작하고 실제 해수와 유사한 2 % 내지 4 %의 염수를 사용하여 그 성능을 조사하였다. 굴절률과 온도를 동시에 측정함으로 온도보상을 신속하게 할 수 있어 염도의 직접측정을 가능하게 하였다. 각기 다른 농도의 염용액에서 측정된 염도의 결과로부터 본 실험의 장치는 안정성과 재현성을 모두 갖는 염도 측정이 가능함을 알았다.
        14.
        2001.03 서비스 종료(열람 제한)
        An on-line refractrometer made of easily obtainable materials is built to determine the salinity and temperature of sea water, and its performance is examined by applying the refractometer to known salt solution. Since refractive index and temperature are measured simultaneously, it is possible to compensate the effect of temperature for accurate measurement. The outcome of salinity measurement for the different concentrations of salt solution indicates that the device is suitable for the salinity measurement by yielding stable and reproducible reading.
        15.
        2000.12 서비스 종료(열람 제한)
        A possibility of the implementation of a quartz crystal sensor to the determination of chemical oxygen demand is examined by checking the electrochemical behavior of the sensor in a glucose solution. Since the surface of a quartz crystal has to be oxidized, a relatively active metal is coated on the surface of a usual 9 MHz AT-cut crystal. The electrochemical behavior is investigated by measuring the changes of current, resonant frequency and resonant resistance while a constant potential is applied. The crystal is installed in a specially designed container, and a quartz crystal analyzer is utilized to measure the frequency and resistance simultaneously. The variations of the measurements are examined at different concentrations of glucose solution, and a proper relation between the concentrations of glucose solution, and a proper relation between the concentration and the measurements is analyzed. As a result, it is found that a linear relation between the concentration of less than 900 ppm and the peak current when a constant potential of -180 mV (SSCE) is applied. The relation can be utilized for the determination of glucose concentration in sea water, and considering a direct relation between gluose concentration and chemical oxygen demand tells a possibility of the measurement of chemical oxygen demand using quartz crystal oscillators.
        16.
        2000.09 서비스 종료(열람 제한)
        Oil spill in sea water is the most frequent and significant problem of marine pollution. As an early detection sensor of the pollution, an activated carbon coated quartz crystal is prepared and examined for its performance of detection sensitivity and stability. Powdered activated carbon and phenol resin is coated on the surface of the sensor and the sensor is baked for an hour. Adsorption of acetone dissolved in water and salt water is measured using frequency shift of quartz crystal at different concentrations of solute material. The outcome indicates that the sensor preparation is adequate and the measurement of solute concentration is stable and sensitive enough to be implemented on the monitoring of solute concentration is stable and sensitive enough to be implemented in the monitoring of organic pollution of sea water.
        17.
        1998.12 서비스 종료(열람 제한)
        A quartz crystal analyzer is utilized to monitor the corrosion process of an aluminum surface of a quartz crystal for marine sensor by sea water. A quartz crystal having 2000 a of aluminum layer is installed in a specially designed cell and is in contact with sea water imitated electrolyte solution. While a constant potential is applied to the cell, the resonant frequency and resonant resistance are simultaneously measured using the quartz crystal analyzer. In addition, surface topographs are taken with an atomic force microscope(AFM) and the element analysis of the surface is conducted using an energy dispersive X-ray spectrometer(EDX). The simultaneous measurement of resonant frequency and resonant resistance during the corrosion process explains the change of surface structure caused by the corrosion. The variation of resonant frequency addresses the amount surface metal dissolution. As a conclusion, it is found that a simple measurement using the quartz crystal analyzer can replace the complex monitoring employing large equipments in the investigation of a corrosion process of sensor surface.
        18.
        1998.10 KCI 등재 서비스 종료(열람 제한)
        본연구에서는 Einstein과 Chien(1954)의 이론은 토대로 하여 하천의 모형연구에 적합한 이동상 모형이론을 수립하였다. 흐름의 상사 ()와 유사이동의 상사 ()의 변화에 따른 총 하상변동량의 거동을 비교함으로써 적용성을 검토하였다. 그 결과 의 값 또는 의 값이 작을 수록 총 사항변동량은 크게 발생하는 것으로 나타났다. 본 연구에서 수립된 모형이론은 각 모형이론의 제한조건을 완화한 것으로서 실험장소 또는 모형사의 제한으로 모형이론을 이상적으로