• 한국융합학회논문지
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• 제11권5호
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• pp.209-217
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• 2020

본 연구의 배경은 드론 시장이 거대해짐에 따라 정부는 '드론 촬영 자유구역 지정'을 논의하고 있으나 법 제도 및 절차, 관련 환경요건들이 상충되거나 명확하지 않아 선행되어야 할 요건들을 정립할 필요성이 제기되었다. 연구목적은 촬영 불가지역 범위를 설정하고 자유구역 지정 및 절차에 관한 선결조건을 제시하는 것이다. 연구방법은 문헌연구를 통해 설문서 구성, 인터뷰를 통해 항목 구체화, 전문가 선택 및 참여자 토의를 통해 조건을 제시한다. 연구결과는 항공안전법 등 개정 2개, 자유구역 지정 기준 및 절차 8개, 안내소 운용 등 4개를 도출하였다. 기대효과는 첫째, 드론 촬영을 항공안전법에 포함으로 자유구역 지정에 관하여 국토부와 협의체 구성이 가능하다. 둘째, 촬영금지 영역을 공중까지 확대하여 입체적인 드론 보안이 가능하다. 셋째, 자유구역 지정을 쉽게 적용할 수 있도록 '용인지역 표준모델'을 제시하였다. 향후 연구방향은 드론 촬영 관련 항공안전법 우선 개정과 국가정보원과 연계한 33개 관할지역의 자유구역지정 절차를 준용하여 추진이 필요하다.

• Bulletin of the Korean Chemical Society
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• 제26권11호
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• pp.1689-1691
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• 2005

1-Butyl-4-aza-1-azoniabicyclo[2.2.2]octane dichromate (BAABOD) 3 is a useful reagent for the selective cleavage of trimethylsilyl ethers and tetrahydropyranyl ethers to their corresponding aldehydes and ketones in the presence of $AlCl_3$ under solvent-free conditions. This method is very simple and efficient and the reaction has been carried out under solvent-free conditions in the presence of a catalytically amount of aluminum chloride.

• Journal of Nutrition and Health
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• 제2권1호
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• pp.19-27
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• 1969

(1) Control values of the hepatic lipids of mouse analysed by means of thin-layer chromatography were as follows: Total cholesterol $5.23{\pm}0.46\;mg/g$ Free cholesterol $4.29{\pm}1.23\;mg/g$ Esterified cholesterol $0.94{\pm}0.30\;mg/g$ Triglycerides $15.56{\pm}1.84\;mg/g$ Free fatty acids $1.26{\pm}0.56\;mg/g$ Phospholipids $29.84{\pm}6.11\;mg/g$ Total lipids $62.44{\pm}12.13\;mg/g$ (2) The garlic administration brought significant elevations in the hepatic contents of free and esterified cholesterds, triglycerides, free fatty acids, and phospholipids in the mouse, when it was injected in excess (2%, 10% suspension) intraperitoneally. (3) The total hepatic lipids of mouse were increased in corelation with the amount of the garlic administered to the animals. (4) A brief discussion was made on the results obtained.

• Journal of Electrochemical Science and Technology
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• 제4권3호
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• pp.89-92
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• 2013

Poly (3,4-ethylenedioxythiophene) (PEDOT) polymers with different electric conductivities were synthesized directly on a FTO substrate via a chemical polymerization method and applied as a platinum (Pt)-free counter electrode for dye-sensitized solar cells (DSSCs). The catalytic properties of the PEDOT as a function of electrical conductivity were studied using cyclic voltammograms, J-V measurements and impedance spectroscopy. The PEDOT counter electrode with around 340 S/cm conductivity exhibited the best performance as a counter electrode for tri-iodide reduction. The ability to modulate catalytic activity of PEDOT with changes in conductivity shows one of promising routes for developing new counter electrode of Pt-free DSSCs.

• Structural Engineering and Mechanics
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• 제13권4호
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• pp.355-368
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• 2002

In this paper, we address the numerical investigation on the effect of liquid compressibility onto the natural frequency of liquid-filled containers. Traditionally the liquid motion has been treated as an ideal fluid motion. However, from the numerical experiments for the axisymmetrical free-vibration of cylindrical liquid-storage tanks, we found that the relative difference in natural frequencies between ideal and compressible motions becomes remarkable, as the slenderness of tank or the relative liquid-fill height becomes larger. Therefore, in such cases of dynamic systems, the liquid compressibility becomes an important parameter, for the accurate vibration analysis. For the free-vibration analysis of compressible liquid-structure interaction we employed the coupled finite element formulation expressed in terms of the acoustic wave pressure and the structure deformation.

• 한국생산제조학회지
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• 제25권6호
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• pp.440-444
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• 2016

Owing to the introduction of various IT devices with emphasis on portability and design, the TFT (thin film transistor liquid crystal display) panel applied to IT devices has the same shape as the product, and the portability requirement of IT devices has resulted in a need for panels with higher rigidity. In this study, the effect of grinding conditions such as the feed rate and edge speed of edge grinding on the surface roughness and chipping of the machined surface is investigated using a metal bond wheel. During edge grinding of alkari-free glass, weak mechanical property of glass results in big chipping owing to generation of tensile stress at the end of grining operation. The results of this study show that the grinding characteristics of alkali-free glass are obtained and meet industry requirements.

• EDISON SW 활용 경진대회 논문집
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• 제4회(2015년)
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• pp.452-459
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• 2015

Thanks to the development of applications, many people are using a smart phone cradle these days. But it has some problems. First of all, it is hard to fix on automobiles. Also, it is vulnerable to external vibration. Recognizing these problems, we decided to improve this device by using FreeCAD and ANSYS. Because FreeCAD is newly invented software, we used another 3D modeling software to cover shortages of tools in FreeCAD. Also, we used famous analysis software 'ANSYS' to analyze bending deformation, modal analysis, and harmonic analysis.

• Advances in Traditional Medicine
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• 제8권1호
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• pp.32-38
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• 2008

Galgeuntang water extract exhibited a strong free radical scavenging activity and reducing power determination. However, a gradual increase in the free radical scavenging activity and reducing power determination was obtained with increasing concentrations. The highest radical scavenging activity was shown by the water extract from Galgeuntang (116.93 ${\mu}g$/mL) and the water extract from Cinnamonum cassia Presl. (95.01 ${\mu}g$/mL). These results of phenolic and flavonoid contents of the extracts indicated that the strong radical scavenging activity of the Cinnamonum cassia Presl. extract might be in part due to the phenolic compounds. The correlation coefficient between TPC and DPPH ($r^2$ = 0.9312), TFC and DPPH ($r^2$ = 0.9677), showed positive correlation among total phenolic/flavonoid contents and antioxidant activity. These results suggest that Galgeuntang has a potential antioxidant activity.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1998년도 Advances in Ginseng Research - Proceedings of the 7th International Symposium on Ginseng -
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• pp.57-62
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• 1998

We hypothesized the primary effect of ginseng was to protect cell membrane fatty acids from decomposition caused by free radicals. To confirm the antioxidant effect of ginseng, we measured the inhibitory effect on the formation of thiobarbituric acid-reactive substances, an indicator of lipid peroxidation, and evaluated the free radical scavenging effect of ginseng by electron spin resonance spectrometer, and gas chromatography. The results showed that thiobarbituric acid-reactive substances formed and the loss of arachidonic acid during lipid peroxidation, and that hydroxyl (-like) radical peak formed by the iron complex (ferric nitrilotriacetate, an known free radical generator in vitro) were completely inhibited by ginseng extract. This antioxidant effect of ginseng may be responsible for its wide pharmacological actions in clinical practice. As the free radical reactions in general are rapid and non-specific, ginseng seems to act as a normalizer, rather than a general tonic, at the stages of acute or chronic active phase of the various diseases.

• Steel and Composite Structures
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• 제32권5호
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• pp.687-699
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• 2019

In this paper, free and force vibration behaviors of graphene-reinforced composite functionally graded (GRC-FG) cylindrical shells in thermal environments are investigated based on Reddy's third-order shear deformation theory (HSDT). The GRC-FG cylindrical shells are composed of piece-wise pattern graphene-reinforced layers which have different volume fraction. Based on the extended Halpin-Tsai micromechanical model, the effective material properties of the resulting nanocomposites are evaluated. Using the Hamilton's principle and the assumed mode method, the motion equation of the GRC-FG cylindrical shells is formulated. Using the time- and frequency-domain methods, free and force vibration properties of the GRC-FG cylindrical shell are analyzed. Numerical cases are provided to study the effects of distribution of graphene, shell radius-to-thickness ratio and temperature changes on the free and force vibration responses of GRC-FG cylindrical shells.