• Title/Summary/Keyword: 환상

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Selective Epoxidation and Reduction of Rigid Cyclic ${\alpha},{\beta}$-Unsaturated Carbonyl Compounds (환상 ${\alpha},{\beta}$-불포화 카르보닐 화합물의 선택적 에폭시화 및 환원)

  • Ma, Eun-Sook
    • YAKHAK HOEJI
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    • v.49 no.6
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    • pp.443-448
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    • 2005
  • Diosgenin (25 (R) - spirost-5-en-3$\beta$ -ol) was oxidized with 2,3-dichloro -5,6-dicyano-1,4-benzoquinone to form 25(R)-1,4,6-spirostatrien-3-one (1) as rigid cyclic $\alpha$,$\beta$-unsaturated carbonyl compound. This compound was reacted with $H_{2}O_{2}$, m-chloroperoxybenzoic acid (mCPBA), NaOCl in the presence with (R,R)- or (S,S)-Jacobsen catalyst, tert-butyl-hydroperoxide (TBHP) in Mo$(CO)_{6}$, and in VO $(acac)_{2}$ catalyst, respectively, 25(R) -1,4,6-spirostatrien -3-one (1) was reduced with $NaBH_{4}$ L-Selectride, $LiAIH_{4}$,$BH_{3}$ $\cdot$$(CH_{3})_{2}S$, Superhydride, Red-Al, and lithium tri-tert-butoxyaluminium hydride. And 25(R)-4,6-spirostadien-3$\beta$-ol (4) was treated with $H_{2}O_{2}$, mCPBA, TBHP in D - (-) - and L-(+)-diisopropyltar-trate and $Ti(OiPr)_{4}$ condition (Sharpless asymmetric epoxidation), TBHP in $Mo(CO)_{6}$, and in $VO(acac)_{2}$ catalyst, respectively.

Sedative Activity of Aporphine and Cyclopeptide Alkaoids Isolated from the Seeds of Zizyphus Vulgaris var. Spinosus, and the Fruits and Stem Bark of Zizyphus Jujuba var. Inermis in mice (산조인 및 대추, 대추나무로부터 단리한 아포르핀과 환상 펩티드 알칼로이드의 생쥐에 대한 진정작용)

  • 한병훈;박명환;한용남
    • YAKHAK HOEJI
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    • v.37 no.2
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    • pp.143-148
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    • 1993
  • The objective of this study was to evaluate the sedative activity of four aporphine alkaloids (APA) and nine cyclopeptide alkaloids(CPA), which had been isolated from the seeds (sanjoin) of Zizyphus vulgaris var. spinosus, and the fruits and stem bark of Zizyphus jujuba var. inermis. The assessment of sedative activity was carried out, employing a hexobarbital-induced sleeping time method in mice. When the relative sedative potency of sanjoinine-A(CPA) was given as one unit, those of nuciferine (APA), lysicamine (APA), chlorpromazine (positive control), and sanjoinine -Ahl (an epimer of sanjoinine-A) were 13, 6.5, 5, and 3, respectively. The sedatvie activities of other CPAs were much lower than those of sanjoinine-A and -Ahl, and other APAs were not active. On heat treatment, nuciferine and lysicamine were degraded into some artifacts which exhibited no sedative activity, while sanjoinine-A was converted into sanjoinine-Ahl which showed more potent sedative activity. These results suggested that nuciferine and sanjoinine-A were major sedative components of native sanjoin, and that sanjoinine-A and its epimeric artifact, sanjoinineAhl were the active principles of roasted sanjoin. It provides a scientific basis for heat-processing (roasting) of this Oriental medicine.

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A Study on the Mythological Image expressed Modern Fashion (현대패션에 나타난 신화적 이미지에 관한 연구)

  • Yang Sook-Hi;Yang Hee-young
    • Journal of the Korean Society of Costume
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    • v.55 no.1 s.91
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    • pp.151-164
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    • 2005
  • In the modern popular culture, a significant code is not the truth itself but the seeming truth. To fulfill this function, it is a mythology that has a transcendental power to eliminate any doubt and mystery. That is to say, cultural uniqueness is understood as an identical thing through mass communication, and people perceive it as a similar cultural community. In this process, mythology form and accumulate the matrix of mythological meaning by eliminating the difference between the reality and the illusion. Such a matrix forces a meaningless and unconditional truth and practice without any criticism and reconsideration. This paper tries to extract art and cultural characteristics of mythological image through examining the relationship among mythological image, history, and ideology. For this aim, we make use of Roland Barthes' signs and Daniel Boorstin's image as a basic analytical tool. After that we examine the characteristics of mythological image appeared in modern cultural discourses and the relationship between mythological image and modern popular culture. Furthermore, we consider the mythological image expressed in modern fashion, which has the nature of commodity aesthetics.

A Study on the Internal Flow Patterns and Heat Transfer Characteristics for a Cylindrical Rotating Heat Pipe (원통형 회전 히트파이프의 내부 유동 및 열전달 특성에 관한 연구)

  • Lee, Jin Sung;Lee, Jae Jun;Kim, Chul Ju
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.9
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    • pp.1217-1228
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    • 1998
  • In order to elucidate the operational characteristics of rotating heat pipes, the internal flow patterns and heat transfer performance are investigated. Flow patterns and its transition are studied with various rotational speeds by visualizing flows established inside a rotating tube. To verify those results of analysis, 2 heat pipes of the same geometries but fill charge rates of 7, 30% were manufactured and submitted to operating tests. Comparison of experimental results on heat transfer rate show a fairly good agreement with the analytical results. The analysis reveals that the optimum charge ratio is ranged in 4~7% depending on the quantity of thermal loads. but the heat pipe with 7% of fill charge ratio reached dry-out limitation at heat flux of $q^{{\prime}{\prime}}=6.2kW/m^2$ lower than that of analytic results. Transition of flow regime was well related to the correlation by Semena & Khmelev on transient centrifugal Froude Number Frc. But hysteresis phenomenon was observed in transition of flow regime, when the rotational speed was stepwisely changed in the way to undergo 1 cycle.

A Numerical Study on Refrigerant Distribution according to the Insertion Depth of the Distributor-Outlet Pipes in an Air-Conditioning System (공조 시스템 내의 분배기 출구관의 삽입깊이에 따른 유량분포연구)

  • Lee, Hee Won;Park, Il Seouk
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.27 no.9
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    • pp.491-496
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    • 2015
  • Generally, the phase of the refrigerants that circulate in air-conditioning systems is repeatedly changed from liquid to gas and from gas to liquid. In vapor-compression refrigeration, the refrigerant at the inlet of the evaporator is in a gas-liquid two-phase state; therefore, to enhance the heat-transfer performance of the evaporator, the even distribution of the refrigerant across multiple passages of the evaporator is essential. Unlike the distribution of a single-phase refrigerant, multi-phase distribution requires further considerations. It is known that the multi-phase distribution at the outlet of the distributor is affected by factors such as the operating condition, the distributor's shape, and the insertion depth of the outlet pipes; here, the insertion depth of the outlet pipes is especially significant. In this study, for a cylindrical distributor with a 90-degree bend entrance and three outlet pipes, the flow uniformity at the outlet pipes was numerically tested in relation to variations of the insertion depth of the outlet pipes.

A Case of Neonatal Sepsis after Operation of Annular Pancreas in Newborn (환상췌장 수술 후 합병된 신생아 패혈증 증례보고)

  • Lee, Chul-Ho;Kim, Wan-Sup;Chung, Eul-Sam
    • Advances in pediatric surgery
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    • v.2 no.1
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    • pp.72-76
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    • 1996
  • Annular pancreas is a rare congenital anomaly with the descending duodenum encircled by a ring of pancreatic tissue, which may cause partial or complete obstruction of the duodenum. In newborn, the symptoms can be those of duodenal stasis resulting from partial intestinal obstruction secondary to some degree of duodenal stenosis. A male newborn weighing 2.0 Kg was born by C-section delivery at 37 weeks' gestation to a 27-year-old mother who had a hydramnios. He was in relatively good condition at birth except regurgitation of saliva and intermittent apnea. A plain film of the abdomen showed the double-bubble of gas filled stomach and proximal duodenum, and upper gastrointestinal series showed a dilated proximal duodenum, with a complete obstruction of the descending duodenum. Intraoperative finding revealed encirclement of the duodenal second portion by pancreatic tissue. Duodenojejunostomy was performed. After the operation, he had developed two serious complications, neonatal septicemia by Enterobacter cloacae on postoperative day 12 and systemic candidiasis on postoperative day 19, and been managed with ventilatory support, antibiotics, and antifungal agents with recovery.

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Rotordynamic Characteristics Analysis for API 610 BB5 Pump Development (API 610 BB5 펌프 개발을 위한 로터다이나믹 특성분석)

  • Kim, Byung-Ok;Lee, An-Sung;Kim, Sung-Ki
    • The KSFM Journal of Fluid Machinery
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    • v.14 no.4
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    • pp.38-44
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    • 2011
  • This paper deals with the detail rotordynamic analysis for BB5 eight stages pump as development of API 610 BB5 type pump. Dry-run analytical model, not considering operating fluid, and wet-run analytical model, considering operating fluid are established. In addition, plain circular and pressure dam bearings are chosen and it was discussed that each bearing has an effect on dynamic characteristics of pump rotor system. A rotordynamic analysis includes the critical speed map, Campbell diagram, stability, and unbalance response. As results, it was predicted that rated speed of the pump rotor passes through 1st critical speed in dry-run condition regardless of bearings, however, it was verified that, in wet-run condition, the rotor system doesn't have critical speeds even if more than twice rated speed. Hence the resonance problem caused by the critical speeds does not happen since actual operating is in wet-run condition including operating fluid. As a result of unbalance response analysis, the pump rotor has stable vibration response at rated speed, regardless of operating fluid and the proposed bearing types.

Group Key Transfer Protocol Based on Shamir's Secret Sharing (Shamir의 비밀 공유 방식의 그룹 키 전송 프로토콜)

  • Kim, Young-Sik
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39B no.9
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    • pp.555-560
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    • 2014
  • Recently, there are many researches on sharing group session key for members in a group. Among them, Harn and Lin proposed a scheme based on the Shamir's group session key and Liu, Cheng, Cao, and Jiang improved it to reduce the specific weakness. Especially, these schemes are based on the finite integer ring to protest the insider attack, in which a valid member can derived another member's secret using known information. In this paper, it is shown that the finite integer ring implies the failure of the reconstruction of group session key depending on the adopted parameters. We fix this problem and propose new group session key transfer scheme using the Shamir's secret sharing.

Uncertainty in the Course of Calibration of RF Multimeter using TVC (열전압변환기를 이용한 고주파전압계의 교정과 측정불확도)

  • 박정규;박석주;이환상;장경승;박명선
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.13 no.1
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    • pp.47-52
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    • 2002
  • It was virtually declared that measurement science must abandon the error analysis of measurement when ISO had published "Guide to Expression of uncertainty in Measurement" International inclination of measurement field in order to guarantee the traceability and confidence of measurement results discards the error concept and instead analyzes the measurement uncertainty. In this paper we establish a mathematical model of measurement and analyze all uncertainty factors as possible as for yielding the measurement uncertainty in the course of the calibration of RF multimeter using Transfer Standard, Thermal Voltage Converter We produce the expanded uncertainty by analyzing cable effects, correlation of thermocoupler and DC meter, DC source, RF source, attenuator, reflection coefficients and DUT.s and DUT.

A Study on the Desire Structure through the Desire Type of Interior Architecture -Focus on the Lacan's Desire-theory- (실내건축의 욕망유형을 통한 욕망구조 특성에 관한 연구 -라깡의 욕망이론을 중심으로-)

  • An, Eun-Hee;Lee, Jung-Wook
    • Korean Institute of Interior Design Journal
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    • v.16 no.4
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    • pp.21-30
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    • 2007
  • `Desire` in this study is not something desire in the used to be-way we can deal with it. This study is to figure out 'desire structure' of interior architecture as a significant measure to interpret the Lacan's desire theory. It is also examines Lacan's concept of desire as defined in the mechanisms of language, in relation to architecture and interior architecture, and in the concept of the objet a(the unattainable object of desire), in the structure of desire as it can be seen in interior architecture. In particular, it analyzed that the desire structure have influenced on some kind of specific desire types what is expressed a characteristic to interior spaces of intimacy, perpetuity, representation, expression. These types reveal the characteristics of desire structure in inner space of interior architecture through negativing and fantasying. The focus on the structure becomes a major issue in almost many kinds of contemporary knowledge-system that starts from the mind to go out to the space in a material or non-meterial(spiritual) way. Therefore, the desire structure reconstructs the Real to make itself through negative and fantastic creation-process. It is important that desire characteristics help detect behind beneath the singularity of interior spaces more than what we know.