• 지질공학
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• 제10권1호
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• pp.27-38
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• 2000

강원도 흥호리 지역의 수리지질과 지하수의 오염취약성을 평가하였다. 연구지역의 주 대수층은 피압 단열암반 대수층으로 지하수 유동과 재충진이 주로 단열을 통해 이루어진다. 순간수위변화시험, 순간 간섭시험 그리고 양수시험을 통해 얻은 대상 대수층의 평균 투수량계수와 저유계수는 각각 3.2$\times$$10^{-3}$~2.0$\times$$10^{-2}$$m^2$/min, 1.3$\times$$10^{-7}$~9.15$\times$$10^{-4}$이다. 거주지역 상부에 위치한 축산단지의 오수로 인해 단열대의 지하수가 오염되었고 오염지하수가 단열대를 통해 이동함에 따라 하부 주민거주지역의 음용 지하수의 오염취약성을 드러내고 있다.

• 센서학회지
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• 제26권6호
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• pp.379-385
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• 2017

In this study, an amperometric non-enzymatic glucose sensor was developed on the surface of a glassy carbon electrode by simply drop-casting the synthesized homogeneous suspension of hexagonal boron nitride (h-BN) nanosheets with a copper metal-organic framework (Cu-MOF) composite. Comprehensive analytical methods, including field-emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), cyclic voltammetry, electrochemical impedance spectroscopy, and amperometry, were used to investigate the surface and electrochemical characteristics of the h-BN-Cu-MOF composite. The FE-SEM, FT-IR, and XRD results showed that the h-BN-Cu-MOF composite was formed successfully and exhibited a good porous structure. The electrochemical results showed a sensor sensitivity of $18.1{\mu}A{\mu}M^{-1}cm^{-2}$ with a dynamic linearity range of $10-900{\mu}M$ glucose and a detection limit of $5.5{\mu}M$ glucose with a rapid turnaround time (less than 2 min). Additionally, the developed sensor exhibited satisfactory anti-interference ability against dopamine, ascorbic acid, uric acid, urea, and nitrate, and thus, can be applied to the design and development of non-enzymatic glucose sensors.

• 식물병연구
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• 제16권1호
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• pp.10-20
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• 2010

Root-knot nematodes cause billions of dollars in crop losses annually have a broad range of host over 2,000 species of plants. These nematodes are known as obligate, sedentary endo-parasites in a plant host to feed upon to complete their life cycle. To prevent the plant parasitic nematode, methyl bromide was widely applied as a soil fumigant. Other strategies to prevent or control nematodes involve RNAi-mediated suppression, R gene transformation, natural products or chemical treatments, the expression of peptide or proteins in susceptible plants, and others. Over the last decade, the entry in GenBank for Meloidogyne reveals 73,340 ESTs and recently two complete Meloidogyne spp. genomes sequences have simultaneously been presented by two groups. Recent works have demonstrated the effect of RNAi suppression to nematode target genes. These results will provide novel members of genes as a foundation for studies focused on understanding the function of M. incognita nematode genes as well as for the development of novel target genes for parasite control. Thus the successful development of biotechnology-derived plants with nematode resistance will result in large yield benefits for producers as well as environmental benefits and will accelerate the research related to pathogensresistant crops.

• Journal of Photoscience
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• 제12권3호
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• pp.137-141
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• 2005

The chemiluminescence reaction of lophine with $H_2O_2$ in alkaline solution has been investigated for use in determination of $Cu^{2+}$ ions. The observed chemiluminescence intensity is found to be a function of the concentration of $Cu^{2+}$. Under the optimum reagent concentrations such as $4{\times}10^{-4}M$ lophine, 0.8 M KOH, 0.2M $H_2O_2,{\lambda}_{em}$, 533nm, the linear range and the detection limit were found to be 0.048ug/ml-48.32ug/ml (R=0.99897) and 0.005ulg/ml respectively. Relative standard deviation for five determinations of 24.16ug/ml $Cu^{2+}$ is 2.35%. The interference from other species was investigated. The proposed method was applied to the determination of $Cu^{2+}$ in different water samples.

• Wind and Structures
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• 제16권3호
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• pp.249-261
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• 2013

Flexible stay cables on cable-stayed bridges are three-dimensional. They sag and flex in the complex wind environment, which is a different situation to ideal rigid cylinders in two-dimensional wind flow. Aerodynamic interference and the response characteristics of wake galloping of full-scale parallel cables are potentially different due to three-dimensional flows around cables. This study presents a comprehensive wind tunnel investigation of wake galloping of parallel stay cables using three-dimensional aeroelastic cable models. The wind tunnel study focuses on the large spacing instability range, addressing the effects of cable separation, wind yaw angle, and wind angle of attack on wake galloping response. To investigate the effectiveness of vibration suppression measures, wind tunnel studies on the transversely connected cable systems for two types of connections (flexibility and rigidity) at two positions (mid-span and quarter-span) were also conducted. This experimental study provides useful insights for better understanding the characteristics of wake galloping that will help in establishing a guideline for the wind-resistant design of the cable system on cable-stayed bridges.

• 한국응용과학기술학회지
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• 제31권2호
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• pp.190-196
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• 2014

The sol-gel method was used to prepare binary metal oxide ($IrO_2-RuO_2$) pH sensor. The electrodes that mole percent compositions (mol%) of $IrO_2$ and RuO2 were 70:30 and 30:70 were selected. The characterizations of Nernstian response over pH range, response rate, interference on alkaline metals and reproducibility were investigated. Also the electroanalytical properties of these electrodes were evaluated in comparison with a commercial glass pH electrode. The composition of $IrO_2:RuO_2$ 70:30 mol% was chosen as better electrode formulation. The electrode was not susceptible to the action of interfering ions such as $Li^+$, $Na^+$ and $K^+$.

• 한국음향학회지
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• 제20권5호
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• pp.14-20
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• 2001

힘평형 서보 가속도계의 성능특성을 결정하는 4개의 팔로 구성된 질량지지 장치를 설계·제작하였다. 팔의 두께와 인가질량의 변화에 따른 질량지지 장치의 응답특성을 유한 요소법을 이용하여 계산하고, 레이저 간섭계를 이용하여 간섭무의 수의 변화와 응답 전압값을 이용하여 가속도계의 응답특성을 측정하였다 팔의 길이와 두께가 변화함에 따라 응답특성은 크게 변화하였으며, 인가질량의 변화는 질량지지 장치의 응답특성변화에 큰 영향을 미치지 못함을 알 수 있었다. 수치해석과 레이저 간섭계로 측정한 공진주파수가 5%차이의 근사한 값을 얻을 수 있었다.

• 폴리머
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• 제30권1호
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• pp.1-9
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• 2006

생체의료용 기능성 고분자재료의 개발에 관한 연구를 고분자의 기능성, 생체적합성 및 생분해성을 토대로 다루었다. 본 연구실에서 합성한 기능성 생분해 고분자들을 비롯하여 생분해성 고분자 생체재료, 온도 감응성 고분자재료, 양이온성 고분자재료, 비축합성 고분자 생체재료, 조직공학을 위한 생체고분자 DNA 매트릭스 및 RNAi 기법을 위한 고분자 등의 기능성 고분자 생체재료에 관련된 연구들을 정리하고, 가까운 장래에 의료용으로 이용될 수 있는 기능성 생체고분자에 대한 연구들을 제안하였다.

• 전력전자학회논문지
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• 제5권6호
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• pp.632-637
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• 2000

본 논문에서는 조광 제어 신호를 기존의 전용선(신호선)이 아닌 일정한 전략선(전원선)를 이용하여 형광등의 밝기를 조절하였다. 전력선에 인가하는 제어선호의 변, 복조는 전력선과 같이 열악한 잡음특성에 강한 내성을 가지고 저속 데이터 전송에 유리한 FSK(Frequency Shift Keying) 디지턴 변조 방식블 채택하여 bit error rate룹 감소시켰디. 안정기의 스위칭 동작에 의해 발생하는 EMI는 일정한 대역의 노이즈를 발생시키므로 본 논문에서는 2단 필터를 사용하여 해딩 대역의 EMI를 50dB로 감쇄시켰다. 전자식 안정기를 이용한 조광제어 방식은 형광등 주변의 회로를 구성시킨 뒤 인버터의 발진 주파수를 18kHZ ~ 25kHz 대역으로 제어함으로써 FL032/T8 램프를 사용하여 실험한 결과 5 ~ 100% 조광이 가능하였다.

• Ocean and Polar Research
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• 제24권3호
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• pp.263-266
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• 2002

Gravity waves have been searched for with a new all-sky camera system over Korean Peninsular. The all-sky camera consists of a 37mm/F4.5 Mamiya fisheye lens with a 180 dog field of view, interference filters and a 1024 by 1024 CCD camera. The all-sky camera has been tested near Daejeon city, and moved to Mt. Bohyun where the largest astronomical telescope is operated in Korea. A clear wave pattern was successfully detected in OH filter images over Mt. Bohyun on July 18, 2001, indicating that small scale coherent gravity waves perturbed OH airglow near the mesopause. Other wave features are since then observed with Na 589.8nm and OI 630.0nm filters. Since a Japanese all-sky camera network has already detected traveling ionospheric disturbances (TID) over the northeast-southwest range of Japanese islands, we hope our all-sky camera extends the coverage of the TID's observations to the west direction. We plan to operate our all-sky camera all year around to study seasonal variation of wave activities over the mid-latitude upper atmosphere.