• Title/Summary/Keyword: Room Constant

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A Study on the Space Planning in the Foodservice Facility (음식서비스공간 개발방안에 관한 연구)

  • 진양호
    • Culinary science and hospitality research
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    • v.4
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    • pp.5-24
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    • 1998
  • Determination of the space requirements for a restaurant is a difficult task. Because the space required is dependent upon many factors which are not constant for all types of restaurants. Today, the guides and procedures that be given are to be regarded as tentative and subject to easy change. This study tired to present the efficient methods and procedures of the space planning of restaurant. Thus, this study is on the purpose of nexts. First, finding the variables involved in the development of the model. Second, describing the approach method of modeling the facility. Third, depicting the methods and procedures of estimating the sizing of serving facilities. Fourth, developing the alternatives of sizing the space required for the facility. As illustrated, this study used the results of the model estimates and emphasized the importance of accurately evaluating the following factors. First, total number of persons to be fe. Second, meal period. Third, number of persons I the dining room. Fourth, number of persons in the serving area. Fifth, vacancy ratio.

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Preparation of Ba2Ti9O20 by Coprecipitation Method (공침법에 의한 Ba2Ti9O20의 합성)

  • 이경희;이병하;오권오
    • Journal of the Korean Ceramic Society
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    • v.25 no.6
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    • pp.671-676
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    • 1988
  • Preparation of high purity ultrafine Ba2Ti9O20 powder was investigated by coprecipitation method. Formation of Ba2Ti9O20 powder from precipitate of coprecipitation takes place at 120$0^{\circ}C$, which is 20$0^{\circ}C$ lower than that from mechanical mixtures of BaCO3 and TiO2. This is apparently due to the nature of the compounds formed by the reaction of mixtures of aqueous solutions of BaCl2 and TiCl4 with an ammoniacal solution of ammonium carbonate and ammouium hydroxide. In this method, the Ba2Ti9O20 powders show low callcining and sintering temperature and it has good sintering and dielectric constant at room temperature.

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Effects of reactant gases on phosphoric acid fuel cell performance (인산형 연료전지의 발전성능에 미치는 반응기체 영향)

  • 송락현;김창수;신동렬
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.45 no.3
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    • pp.374-379
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    • 1996
  • Effects of reactant gas flow rates and starvation on phosphoric acid fuel cell performance were studied. As the reactant gas flow rates increased, the cell performance increased and then the cell maintained constant performance. The optimum flow rates of hydrogen, oxygen and air under galvanostatic condition of 150 mA/cm$_{2}$ are found to be 5cc/min cm$_{2}$ 5cc/min cm$_{2}$ and 15cc/min cm$_{2}$ at room temperature and 1 atm, respectively. Also the open circuit voltage of single cell decreased with increasing oxygen flow rate due probably to the decreased probably to the decreased oxygen pressure in the cathode side. Hydrogen and oxygen starvation resulted in voltage loss of about 5mV and 0-2mV, respectively. The voltage loss was independent of starvation time. These results were discussed from point of view of electrochemical reaction of the cell. (author). 9 refs., 8 figs.

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Electrochemical and Spectroscopic Studies on the Interaction between DNA and the Product of Enzyme-catalyzed Reaction of OPD-H2O2-HRP

  • Niu, S.Y.;Zhang, S.S.;Ma, L.B.;Jiao, K.
    • Bulletin of the Korean Chemical Society
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    • v.25 no.6
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    • pp.829-832
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    • 2004
  • The pure product of 2,3-diaminophenazine was prepared by the enzyme-catalyzed reaction of ophenylenediamine-$H_2O_2$-horseradish peroxidase and characterized by UV/Vis spectroscopy, IR spectroscopy and NMR spectroscopy. The electrochemical behaviour of 2,3-diaminophenazine on the glassy carbon electrode was studied. The interaction between 2,3-diaminophenazine and deoxyribonucleic acid was studied by cyclic voltammetry method and UV/Vis spectroscopy, which indicated that the interaction between them is intercalation. The influence of reacting time was also studied. The binding ratio of the 2,3-diaminophenazine-DNA complex is calculated to be 1 : 2 and the binding constant is to be $5.07{\times} 10^3L{\cdot}mol^{-1}$ at room temperature.

Propylene Hydrogenation over Cubic Pt Nanoparticles Deposited on Alumina

  • Yoo, Jung-Whan;Lee, Sung-Min;Kim, Hyung-Tae;El-Sayed, M.A.
    • Bulletin of the Korean Chemical Society
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    • v.25 no.6
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    • pp.843-846
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    • 2004
  • Pt nanoparticles loaded on alumina through an impregnation at room temperature was prepared using $K_2PtCl_4$ and acrylic acid as capping material. Transmission electron microscopy showed that the deposited Pt particles indicate ca. 80% cubic shapes with a narrow distribution of 8-10 nm in size. Propylene hydrogenation over the catalyst has been carried out to evaluate their catalytic performance by the values of activation energy. It is determined from the initial rate, reaction order, and rate constant and is found to be $9.7{\pm}0.5$ kcal/mol. This value has been discussed by comparing to those of encapsulated- and truncated octahedral Pt nanoparticles deposited on alumina, respectively, to study influence of the particle size and shape, and capping material used on the activation energy.

Raman Frequencies Calculated at Various Pressures in Phase I of Benzene

  • Tari, Ozlem;Yurtseven, Hamit
    • Journal of the Korean Chemical Society
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    • v.57 no.2
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    • pp.204-209
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    • 2013
  • We calculate in this study the pressure dependence of the frequencies for the Raman modes of A ($A_g$), B ($A_g$, $B_{2g}$) and C ($B_{1g}$, $B_{3g}$) at constant temperatures of 274 and 294K (room temperature) for the solid phase I of benzene. Using the mode Gr$\ddot{u}$neisen parameter of each lattice mode, which correlates the pressure dependence of the crystal volume and the frequency, the Raman frequencies of those modes are computed for phase I of benzene. Our results show that the Raman frequencies of the three lattice modes (A, B and C) increase as the pressure increases, as expected. The temperature effect on the Raman frequencies is not significant, which can be explained by the experimental measurements.

An Analysis of Indoor Thermal Environment by Macro Model (매크로 모델에 의한 실내온열환경 검토)

  • Jung, Jae-Hoon
    • Proceedings of the SAREK Conference
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    • 2008.11a
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    • pp.584-589
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    • 2008
  • It is known that slab thermal storage which uses concrete slab as thermal material is effective in the load leveling and using the nighttime electric power. The temperature distribution is not constant in plenum in thermal storage time by beams, ducts such as several factor. It is considered that this fact will effect on efficiency of thermal storage and indoor thermal environment. The purpose of this paper is to examine the thermal environment inside plenum. A macro model was made for the analysis of indoor thermal environment as the first step. The flow rate distribution and temperature distribution of object room model was examined by use of basic equations such as airflow by the pressure difference between unit cells, heat flow by air and heat transfer.

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Synthesis, Optical and Electrical Studies of Nonlinear Optical Crystal: L-Arginine Semi-oxalate

  • Vasudevan, P.;Sankar, S.;Jayaraman, D.
    • Bulletin of the Korean Chemical Society
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    • v.34 no.1
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    • pp.128-132
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    • 2013
  • L-Arginine semi-oxalate (LASO) single crystal has been grown by solution growth technique at room temperature. The crystal structure and lattice parameters were determined for the grown crystal by single crystal X-ray diffraction studies. Photoluminescence studies confirm the violet fluorescence emission peak at 395 nm. Optical constants like band gap, refractive index, reflectance, extinction coefficient and electric susceptibility were determined from UV-VIS-NIR spectrum. The dielectric constant, dielectric loss and ac conductivity of the compound were calculated at different temperatures and frequencies to analyze the electrical properties. The solid state parameters such as plasma energy, Penn gap, Fermi energy and polarizability were calculated to analyze second harmonic generation (SHG). Nonlinear optical property was discussed to confirm the SHG efficiency of the grown crystal.

Electrical Properties of (N-docosyl quinolinium)-TCNQ(1 :2) Charge Transfer Complex Langmuir-Blodgett Films ((N-docosyl quinolinium)-TCNQ(1:2) 전하 이동 착물 Langmuir-Blodgett막의 전기적 특성)

  • 정순욱;정회걸
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.11a
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    • pp.143-146
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    • 1999
  • In this study, Ultra-thin films of (N-ducosyl quinolinium)-TCNQ(1:2) complex were prepared on the hydrophilic substrate by Langmuir-Blodgett(LB) technique. By measure of UV-vis spectra and capacitance, deposition status was confirmed together with the thickness of natural oxidized aluminum film inside a device and dielectric constant of (N-docosyl quinolinium)-TCNQ(1:2) complex. The electrical properties of (N-docosyl 7uin7linium)-TCNQ(1:2) complex were investigated at room temperature. The conductivity of this film measured by the direction uf either vertical or horizontal axis is results in a quite different value.

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Fatigue Behavior of Alumina Ceramics under the Repeated Dynamic Loading (반복 동적하중에 의한 알루미나 세라믹스의 피로거동)

  • 이규형;박성은;이홍림
    • Journal of the Korean Ceramic Society
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    • v.35 no.8
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    • pp.850-856
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    • 1998
  • The dynaamic fatigue behavior of alumina ceramics was observed at room temperature using four-point bending method. Dynamic fatigue fracture strength was observed as function of down speed and notch length. The crack growth exponent of the specimens was calculated from the fracture strength and lifetime in dynamic fatigue test. After loading the stresses in the range of 0% to 105% compared with the average in-ert strength the value of residual fracture strength was measured for unnotched and 0.5mm notched speci-mens at the 0.001 and 0.0005 mm/min down speed respectively. After the 95% stress of the average inert strength was applied repeatedly the value of rsidual fracture strength was measured for 0.5mm notched specimens at the 0.001 and 0.0005 mm/min down speed respectively. The material constant A was found to be almost the same and not to depend on the loading mode or the down speed for unnotched and notched specimen. The value of fracture strength with time calculated from the constants n and A was in good agreement with the measured value.

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