• Bulletin of the Korean Chemical Society
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• v.35 no.3
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• pp.949-952
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• 2014

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3524-3526
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• 2011

• Journal of the Korean Chemical Society
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• v.30 no.2
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• pp.259-262
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• 1986

• Korean Journal of Pharmacognosy
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• v.8 no.2
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• pp.49-53
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• 1977

A triterpenoid compound$(C_{30}H_{50}O)$ was isolated from the hydrocarbon and alcohol fraction of the roots of $Codonopsis\;lanceolata\;B_{ENTH}$. et $H_{OOK}$. (Campanulaceae) and it was identified as cycloartenol by physico- chemical data.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10c
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• pp.226-228
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• 2001

본 논문에서는 설치가 용이하고, 이동이 자유로우며 능동적으로 연결을 맺을 수 있는 문선 LAN환경 특성에 대해 알아보고, 무선LAN에서의 TCP 버전별 특성을 분석해 보았다. 또한 지연과 오류 확률이 높은 무선 LAhN 환경에서 여러 가지 버전의 TCP가 동시에 사용되는 경우에 각 TCP 버전의 트래픽 특성을 모의 실험하였다. 이 실험을 위해 가장 많이 사용되어지고 있는 네트워크 시뮬레이터2(NS2)를 이용하였다.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.917-920
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• 2004

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.11
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• pp.1088-1093
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• 2014

The structure of the fire control system(FCS) of a light armed helicopter and effective logistics support was taken into account in the proposed common weapon interface module(CWIM) for a distributed FCS. The pros and cons of a distributed FCS and a centralized FCS were analyzed, then a CWIM which can be applied to the weapon interface module of a distributed FCS was designed and fabricated. Integration tests between the proposed CWIM and a weapon simulator were conducted to ascertain whether or not the proposed CWIM could be applicable to a distributed FCS. We expect that the CWIM design approach method secured through this study will be helpful in mitigating cable work of the FCS which will be applied to a Light Armed Helicopter and controlling various weapons.

• Bulletin of the Korean Chemical Society
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• v.14 no.4
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• pp.469-475
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• 1993

The approximate rates and stoichiometry of the reaction of excess lithium tris(diethylamino)aluminum hydride (LTDEA) with selected organic compounds containing representative functional groups under standardized condition (tetrahydrofuran, 0$^{\circ}C$) were examined in order to define the characteristics of the reagent for selective reductions. The reducing ability of LTDEA was also compared with those of the parent lithium aluminum hydride (LAH) and lithium tris(dibutylamino)aluminum hydride (LTDBA). In general, the reactivity toward organic functionalities is in order of LAH${\gg}$LTDEA${\geq}$LTDBA. LTDEA shows a unique reducing characteristics. Thus, benzyl alcohol and phenol evolve hydrogen slowly. The rate of hydrogen evolution of primary, secondary, and tertiary alcohols is distinctive: 1-hexanol evolves hydrogen completely in 6 h, whereas 3-hexanol evolves hydrogen very slowly. However, 3-ethyl-3-pentanol does not evolve any hydrogen under these reaction conditions. Primary amine, such as n-hexylamine, evolves only 1 equivalent of hydrogen. On the other hand, thiols examined are absolutely inert to this reagent. LTDEA reduces aldehydes, ketones, esters, acid chlorides, and epoxides readily to the corresponding alcohols. Quinones, such as p-benzoquinone and anthraquinone, are reduced to the corresponding diols without hydrogen evolution. However, carboxylic acids, anhydrides, nitriles, and primary amides are reduced slowly, where as tertiary amides are readily reduced. Finally, sulfides and sulfoxides are reduced to thiols and sulfides, respectively, without evolution of hydrogen. In addition to that, the reagent appears to be an excellent partial reducing agent to convert esters, primary carboxamides, and aromatic nitriles into the corresponding aldehydes. Free carboxylic acids are also converted into aldehydes through treatment of acyloxy-9-BBN with this reagent in excellent yields.

• Journal of Aerospace System Engineering
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• v.17 no.4
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• pp.110-117
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• 2023

In this paper, the optimal placement of the rotary wing's communication and navigation antennas was evaluated by measuring their performance through ground simulations and flight tests. To select the mounting position of the communication and navigation antenna on the helicopter, after considering the shape and characteristics of the airframe, the radiation patterns, coupling analysis, equipment operation profiles, and antenna type analysis were performed for the aircraft-mounted antenna. Based on the analysis results, a procedure for sequentially performing voltage standing wave ratio (VSWR) measurement and antenna pattern test was established through ground and flight tests of the antenna. The systematic performance measurement method and procedure proposed in this paper were verified through ground and flight tests of the Light Armed Helicopter (LAH) system.

• Archives of Pharmacal Research
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• v.10 no.1
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• pp.29-35
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• 1987

The effect of drug addition on the bovine serum albumin (BSA)-edible dye complex was studied by spectrophotometric method. The edible dyes tested were amranth, erythrosine, tatrazine and sunset yellow. The moles of bound dye per protein mole and free energies for edible dyes bounded were determined at pH 7.4. The values of free energy change by the addition of drughs to BSA-edible dye were ranged fro -6, 260 to 08030 cal/mole. In the wide range of edible dye concentration (0.3-$7{\times}10^{-5}$$^{-5}$ M), acetylsalicylic acid (ASA) showed pattern of displacement different from that of dye. It was assumed that ASA has different binding mechanisms from edible dye.