• Natural Product Sciences
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• v.18 no.4
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• pp.233-238
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• 2012

Nine compounds (1 - 9), ${\alpha}$-linolenic acid (1), cis-5,8,11,14,17-elcosapentaenoic acid (2), phytol (3), loliolide (4), uridine (5), thymidine (6), deoxyadenosine (7), adenine (8), and adenosine (9), were isolated from the n-hexane, methylene chloride, ethyl acetate and n-butanol fractions of Capsosiphon fulvescens. The structures of these compounds were elucidated on the basis of spectroscopic evidence. Compounds 1 - 9 exhibited acetylcholinesterase (AChE) inhibitory activities with $IC_{50}$ values ranging from 114.91 to $252.40{\mu}M$, whereas 2 - 4 showed butyrylcholinesterase (BChE) inhibitory activities with $IC_{50}$ values ranging from 251.18 to $499.16{\mu}M$.

• Journal of the Optical Society of Korea
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• v.20 no.1
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• pp.204-211
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• 2016

Oil pollution seriously endangers the biological environment and human health. Due to the diversity of oils and the complexity of oil composition, it is of great significance to identify the oil contaminants. The 3-D fluorescence spectrum combined with a second order correction algorithm was adopted to measure an oil mixture with overlapped fluorescence spectra. The self-weighted alternating trilinear decomposition (SWATLD) is a kind of second order correction, which has developed rapidly in recent years. Micellar solutions of #0 diesel, #93 gasoline and ordinary kerosene in different concentrations were made up. The 3-D fluorescence spectra of the mixed oil solutions were measured by a FLS920 fluorescence spectrometer. The SWATLD algorithm was applied to decompose the spectrum data. The predict concentration and recovery rate obtained by the experiment show that the SWATLD algorithm has advantages of insensitivity to component number and high resolution for mixed oils.

• The Plant Pathology Journal
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• v.23 no.3
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• pp.219-222
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• 2007

A total of the 261 Phytophthora infestans isolates collected from 2003 to 2005 in Korea were investigated for their physiological race composition. Among the isolates, we detected 18 physiological races and the dominant races were R0.1.3.5.6.10.11 and R0.1.3.5.6.7.10.11 with frequencies of 18.4% and 11.4%, respectively. All of the P. infestans races carried multiple virulence genes and showed virulence to the potato resistance genes R1, R3, R5, R6, R7, R10 and R11, but not to R8 and R9. Therefore, it is likely that the physiological races of P. infestans were diverse in Korea.

• Proceedings of the KIEE Conference
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• 2006.04a
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• pp.126-128
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• 2006

For pattern matching, an object image should be segmented and analyzed for the first time. Thresholding is a fundamental approach to segmentation that utilizes a significant degree of pixel popularity or intensity. Otsu's thresholding is one of the most veil-known methods proposed in the literature. However, the method has a disadvantage of repeatedly searching the optimal thresholds for the entire region. To overcome this problem, a number of methods have been proposed. In this paper, we propose a simple and fast thresholding method of finding multi-level threshold values by extending the Otsu's method. Our experimental results for the benchmak images show a possibility that the proposed method could be used efficiently for pattern matching.

• Smart Structures and Systems
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• v.19 no.4
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• pp.415-429
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• 2017

This paper focuses on the impact of the wave passage effect on the long-span bridge. In order to make the wave passage effect more obvious, ground motion samples are selected from the near-fault ground motion of the 1999 Chi-Chi earthquake and an arch bridge with a 280m main span is selected as a bridge sample. The motion ground samples are divided into two groups according to the characteristics of near-fault. A sequence of fragility curves is developed. It is shown that the seismic damage is increased by the wave passage effect and the increase is more obvious in the near-fault ground motion.

• Proceedings of the Korean Information Science Society Conference
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• 2010.06b
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• pp.283-288
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• 2010

본 논문은 VTK를 이용한 3차원 무릎 MRI 가시화에 대한 프로그램 기술을 제안한다. 기존의 많은 연구에서는 VTK를 사용하여 의료영상에 대한 3차원 가시화 프로그램을 제안하였으나 골관절염 진단을 목표로 한 무릎 3차원 가시화 방법은 아직 많이 제안되지 않고 있다. 본 논문에서는 볼륨렌더링(Volume redering) 기술과 다각형렌더링(Polygonal rendering)기술을 융합하여 무릎 및 연골을 효과적으로 가시화 할 수 있는 방법을 제안한다. 프로그램은 사용자 상호작용이 가능하고 VTK를 이용한 GPU기반의 프로세싱을 기반으로 하기 때문에 실시간 렌더링이 가능하다. 실험결과로부터 제안한 3차원 가시화 기술은 연골과 무릎의 관계를 직관적으로 표현할 수 있어 골관절염 조기진단에 유용하게 사용될 것으로 기대한다.

• Journal of Power Electronics
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• v.16 no.5
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• pp.1735-1742
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• 2016

This paper proposes an interleaved five-level boost converter based on a switched-capacitor network. The operating principle of the converter under the CCM mode is analyzed. A high voltage gain, low component stress, small input current ripple, and self-balancing function for the capacitor voltages in the switched-capacitor networks are achieved. In addition, a three-loop control strategy including an outer voltage loop, an inner current loop and a voltage-balance loop has been researched to achieve good performances and voltage-balance effect. An experimental study has been done to verify the correctness and feasibility of the proposed converter and control strategy.

• Journal of Community Nutrition
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• v.8 no.4
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• pp.207-213
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• 2006

The present study was conducted to investigate the effect of oolong tea extract on blood glucose level and antioxidant system in diabetic rats. The Sprague-Dawley rats were fed on AIN-76 based experimental diets containing 1 % oolong tea extract for 6 weeks. They were induced to be diabetic by receiving streptozotocin (45mg/kg BW) intramuscularly. Blood glucose, blood and hepatic concentration of vitamins A and E, and antioxidant enzyme activities were measured. Oolong tea extract feeding decreased the plasma glucose in diabetic rats. Dietary supplementation of oolong tea extract did not affect antioxidative enzyme activities such as superoxide dismutase, glutathione peroxidase and catalase in diabetic rats. The plasma level of retinol was increased in diabetic rats by feeding oolong tea extract. Plasma and hepatic levels of ${\alpha}$-tocopherol were higher in diabetic rats fed oolong tea extract. In conclusion, these results suggest that oolong tea extract consumption might reduce the plasma glucose in diabetic rats and protect the oxidative damage from diabetic stress to some extent.

• Proceedings of the Korea Contents Association Conference
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• 2017.05a
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• pp.57-58
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• 2017

중국 경극에서 얼굴에 다양한 분장을 하는 것을 검보라 하며, 극 중에서는 다양한 상징성을 갖는다. 검보는 민족적 특색을 내재하며, 극중 캐릭터를 위한 "영혼의 화면"이라 불린다. 반면, 일본 노극은 가면을 쓰고 연기하는 독특한 고전 가무극으로 히타멘(直面, 가면을 쓰지 않음)과 가면을 쓰는 공연으로 나뉘며, '유현(幽玄)의 예술" 이라고 불린다. 이러한 경극의 검보와 노극의 가면은 애니메이션에 캐릭터에 차용되며, 극의 서사와 상징성을 드러내는 매개 역할을 하고 있다. 이에, 본 연구에서는 경극의 검보와 노극의 가면이 연출된 애니메이션 영화를 중심으로 사례 비교연구를 진행하고자 한다.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.230-235
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• 2000

In this paper, a surface generation model is presented to simulate surface roughness profile in turning operation. The simulation model takes into account the effect of tool geometry, process parameters, rotational errors of spindle, and the relative vibration between the cutting tool and workpiece. The surface roughness profiles are simulated based on the surface-shaping system. The model has been verified by comparing the experimental values with the simulation values. It is shown that the surface simulation model can properly predict the surface roughness profile.