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Formation of Medium Chain Fatty Acid by Wine Yeasts (포도주 효모에 의한 중간크기의 지방산 생성)

  • Lee, Soo-O
    • Korean Journal of Food Science and Technology
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    • v.21 no.6
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    • pp.832-837
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    • 1989
  • It has been suggested that medium chain fatty acid(MCFA) may be toxic to yeast and bacteria and thus play a role in the inhibition of alcoholic and malolactic fermentations and also important contributors to wine flavour We measured, by the use of GLC, the concentrations of octanoic, decanoic and dodecanoic acids produced by 12 wine yeast strains during the alcoholic fermentation of a grape juice-like medium. In general, there was a high production of MCFA at first, dropping dramatically later. The formation of MCFA is largely dependent on yeast strain but it also depends upon temperature, sugar concentration, stirring and carbon dioxide sparging.

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Magnetic Characteristics of an InSb Hall Device of Multilayerd Structure (다충구조 InSb 홀소자의 제작과 특성)

  • 이우선;김상용;서용진;박진성;김창일
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.8
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    • pp.681-687
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    • 2000
  • Magnetic Characteristics of an InSb hall device of multilayered structures were investigated. For the measurement of electrical properties of the hall device InSb thin films fabricated with series and parallel multilayers wee evaporated. Hall coefficient hall mobility carrier density and hall voltage were measured as a function of the intensity of magnetic field. We found that the XRD analysis of InSb thin film showed good properties at 20$0^{\circ}C$ 60 minutes. Resistance of ohmic contact was increased linearly due to increasing current. Hall voltages at 0.01 T showed 5$\times$10$^{-4}$ [V] and $1.5\times$10$^{-3}$ [V]. Some of device fabrication technique and analysis of magnetic characteristics were discussed.

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유리섬유/에폭시 복합절연재료의 계면 접착력 개선에 관한 연구 1

  • 이종호;황영한;이규철
    • Electrical & Electronic Materials
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    • v.8 no.2
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    • pp.136-143
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    • 1995
  • With the contact angle of phase dropping epoxy resin on the inorganic filler(glass plate) surface treated with air plasma, we have studied about the interfacial wettability between epoxy resin and glass plate as a simple model of glass fiber reinforced composite materials. The contact angle on the inorganic filler surface varied with surface treatment conditions. The contact angle significantly depends on plasma treating time and environment temperature in the oven. From the view point of plasma treatment condition in this work, when discharge conditions were pressure 200mtorr, voltage 800V, magnetic flux density 8OGauss, optimum treatment time were proved as 3,4 and 5 minutes for the environment of >$80^{\circ}C$, >$100^{\circ}C$ and >$120^{\circ}C$, respectively.

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Comparison of Transient Stability Enhancement by Series/Shunt Compensation and PSS Application for Step Out Instability Phenomena (동기 탈조 불안정 현상의 직.병렬 보상과 PSS에 의한 안정화 효과 분석)

  • Oh, Tae-Kyoo;Kim, Hak-Man;Lee, Young-Woon;Kim, Young-Ju;Chu, Jin-Boo
    • Proceedings of the KIEE Conference
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    • 1997.07c
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    • pp.844-847
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    • 1997
  • Countermeasure for instability due to sudden changes like electric short circuit, line switching, generation/load dropping etc. in power systems have been sought in terms of intentional or controlled network changes such as series/shunt compensation and generation/load rejection etc. This paper presents the comparison of stability improving effects by series and shunt compensation for the first swing step out phenomena of a large capacity generating station.

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The Control of Temperature of Green Roof System with the Roof Slab Insulation Method (옥상슬래브 단열조건에 따른 옥상녹화의 열환경 조정효과)

  • Yeo, In-Ae;Cho, Hong-Je;Yoon, Seong-Hwan
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.869-872
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    • 2008
  • On this study, the Control of Temperature is specified on the view of indoor comfort and building energy consumption. It is estimated by Dynamic heat load simulation which has the factors of insulation method and the soil thickness of the green roof system. The fact that the model which has no insulation has the greatest effect of dropping high temperature and the cooling load decrease is confirmed.

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Synthesis of New ${\alpha}$-Amidoketenes Using Malonyl Dihalide (Malonyl Dihalide를 이용한 새로운 ${\alpha}$-Amidoketenes의 합성)

  • Oh, Mi-Jung;Park, Myung-Sook
    • YAKHAK HOEJI
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    • v.55 no.2
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    • pp.127-130
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    • 2011
  • We synthesized new ${\alpha}$-amidoketenes using dehydrochlorination from anilines, triethylamine and malonyl dichloride under $0^{\circ}C$. The utility of ketenes in both laboratory and industrial practice was quickly recognized, and these species have been extensively utilized, including as pharmaceutical intermediates and anti-cancer agents. All synthetic process from anilines to ${\alpha}$-amidoketenes could be carried out by one-pot reaction. Synthetic ketenes 2a~f were identified using NMR and IR spectrum. Formation of ketenes was undertaken with dropping of malonyl dichloride at $0^{\circ}C$ in methylene chloride for 0.5~4 h. Using malonyl dichloride was better than using diethyl malonate as a synthetic reagents for the ketenes.

Production of Ag- Ni fine powder by coprecipitation (공침법을 이용한 Ag-Ni 초미분 제조)

  • Kim, Bong-Seo;Woo, Byung-Chul;Byun, Woo-Bong;Lee, Hee-Woong
    • Proceedings of the KIEE Conference
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    • 1994.07b
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    • pp.1342-1344
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    • 1994
  • Silver-Nickel alloy has been used as a electrical contact material for low voltage, low current. Since the solubility between Ag and Ni is very low, it is difficult to produce Ag-Ni alloy by using conventional melting method and disperse Ni powder homogeneously in Ag matrix. In this study we have been produced fine Ag-Ni alloy powder by using coprecipitation method. Firstly, we have produced silver-nickel nitrate solution by dissolving the Ag and Ni ingot in nitric acid solution and then, coprecipitate (Ag, Ni)carbonate dropping Ag-Ni nitrate solution to sodium carbonate solution. (Ag, Ni) carbonate is heat-treated in $H_2$ atmosphere, $400^{\circ}C$ and it has been analysed by TGA, SEM, XRD, ICP. It is represented Silver-Nickel alloy powder in the particle range of $0.1{\sim}0.5{\mu}m$.

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The Mechanism for TCP-UDP Fairness Improvement in the Assured Service of the Diffserv Network (차등 서비스 네트워크의 확신 서비스에서 TCP-UDP 공평성 향상 기법)

  • 모상덕;정광수
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.04a
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    • pp.481-483
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    • 2004
  • 본 논문에서는 차등 서비스 네트워크(Diffserv network)의 확신 서비스(assured service)에서 발생할 수 있는 TCP와 UDP 플로우 사이의 공명성 문제를 해결하기 위한 TRBD(Target Rate-based Dropping) 기법을 제안한다. 차등 서비스 네트워크의 확신 서비스에서의 공평성 향상에 대한 기존 연구는 마킹 확률을 변경하여 공평성을 향상시키는 연구가 중심이 되어 왔다. 이러한 연구들은 코어노드에서의 큐 관리를 위하여 주로 MRED(Multiple RED)골 이용하기 때문에 TCP 및 UDP, 목표 전송률 등에 대한 고려가 부족하다. 본 논문에서 제안하는 TRBD 기법은 코어노드에서 목표 전송률에 따라 UDP의 폐기 확률을 조정하여 TCP-UDP 공평성 및 목표 전송률을 고려한 공평성을 향상시킬 수 있다. ns 시뮬레이터를 이용한 실험을 통하여 TRBD 기법의 TCP-UDP 공평성 향상을 확인하였다.

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Evaluation of Floor Impact Sound Performance according to the Reduction Methods (바닥충격음 저감방안에 따른 성능평가)

  • Choi Gyoung-Seok;Choi Hyun-jung;Yang Kwan-Seop;Kim Kyoung-Woo
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.14 no.9 s.90
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    • pp.811-818
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    • 2004
  • Impact sounds, such as those created by footsteps, the dropping of an object or the moving of furniture, can be a source of great annoyance in residential buildings. The character and level of impact noise generated depends on the object striking the floor, on the basic structure of the floor, and on the floor covering. This study base on the evaluate of isolation performance of impact sound according to the impact noise reduction methods. Reduction methods consist of four ways. First way is increase thickness of bare floor and other ways are using the soft coverings on the floor and ceiling assembles. Last way is make floating floor with shock absorbing materials.

A Methodology and Reliability for Selecting the Optimal Model among Ten Models of Crushing Machine with Various Constraints (다양한 제약조건을 갖는 열개의 파쇄장비 모델들 중 최적 모델 선정을 위한 방법과 신뢰성)

  • Leem Young Moon;Hwang Young Seob
    • Journal of the Korea Safety Management & Science
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    • v.7 no.1
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    • pp.159-166
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    • 2005
  • It is not difficult to see the road repairing. There are many and various machines which crush road surface. The efficiency and power of the machine depend on crushing head-shape, crushing interval, crushing load, crushing stress, machine's dropping height and roller's kind. The objective of this study is to select the optimal model among ten models of crushing machine with constraints such as crushing depth, variation, and crushed particle size. And then this paper provides the valid theoretical base on selected model. The data for this study are chosen from the site of construction in Kangnung during three months (2004. 6. 1${\~}$2004. 8. 31). The provided methodology in this paper will be fruitful not only for the selection of crushing machine but also for the aspects of construction period, cost, work efficacy according to the condition from the various sites of construction.