• Title/Summary/Keyword: D-H Method

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Analysis of Cyclic Adenosine Monophosphate (cAMP) Separation via RP-HPLC (reversed-phase high-performance liquid chromatography) by the Moment Method and the van Deemter Equation (역상 크로마토그래피에서 모멘트 방법과 van Deemter 식을 이용한 고리형 아데노신 일인산의 분리특성 연구)

  • Lee, Il Song;Ko, Kwan Young;Kim, In Ho
    • Korean Chemical Engineering Research
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    • v.53 no.6
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    • pp.723-729
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    • 2015
  • The moment analysis of cyclic adenosine monophosphate (cAMP) was performed using chromatograms that were obtained with the pulse input method from an octadecyl silica (ODS) high-performance liquid chromatography (HPLC) column. The general rate (GR) model was employed to calculate the first absolute moment and the second central moment. Three important coefficients for moment analysis, which are molecular diffusivity ($D_m$), external mass transfer coefficient ($k_f$), and intra-particle diffusivity ($D_e$), were estimated by the Wilke-Chang equation, Wilson-Geankoplis equation, and comparing van Deemter equation to theoretical plate number equation, respectively. Experiments were conducted by various conditions of flow rates, methanol volume ratio of the mobile phase, and solute concentration. After the moment analysis, results were organized by van Deemter plots. Also van Deemter coefficients were compared each other to effect $H_{ax}$, $H_f$, and $H_d$ on height equivalent to a theoretical plate (HETP, $H_{total}$). The value of intraparticle diffusion ($H_d$) was the primary factor which makes for HETP whereas external mass transfer ($H_f$) was disregardable factor.

Three-Dimensional Medical Visualization Method on PC (PC기반의 3차원 의학영상 가시화 방법에 관한 연구)

  • Lee, J.H.;Lee, S.H.;Lee, T.S.;Choi, I.T.;Park, S.K.
    • Proceedings of the KOSOMBE Conference
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    • v.1998 no.11
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    • pp.259-260
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    • 1998
  • In this paper, we present a 3D visualization method of medical image on PC. Using morphological method, we used to segment 2D medical images (X-ray CT, MRI). Presented method is treating in some detail two operations : dilation and erosion. Also known as an isosurface, using a constant density surface make a target organ in 3D. In the whole procedure for visualization. The medical images are implemented by using Visual C++ 5.0 in activeX and IDL(interactive data language) under PC environment.

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[ $H{\infty}$ ] Control of Level Maintaining Device (수평유지장치의 $H{\infty}$ 제어)

  • Oh, Young-Jin;Suh, Young-Soo
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.52 no.2
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    • pp.77-84
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    • 2003
  • This paper is concerned with level control of a upper plate in a vehicle. The objective of control is to maintain the upper plate at level regardless of road slopes. The road slope is detected using an accelerometer-type inclinometer and H infinity control method is used to simultaneously reduce effects of road slopes and sensor noises. By the simulation, it is shown that the upper plate is successfully maintained at level.

Comparison of Bentgrass Recovery Speed on Golf Green Followed by Methods of Ball Mark Repair Practise (골프장 그린의 볼마크 수리방법에 따른 벤트그래스의 회복속도 비교)

  • Park, Jong-Hwa;Lee, Jae-Phil;Kim, Doo-Hwan;Joo, Young-Kyoo
    • Asian Journal of Turfgrass Science
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    • v.24 no.2
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    • pp.211-217
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    • 2010
  • This study was conducted to investigate a proper method of ball mark repair by comparing the creeping bentgrass recovery speed on golf course green treated by various methods of ball mark repair. Nine general repairing methods were tested and compared; control (no repair, A type), two common methods of USGA (B type) and GCSAA (C type), three methods with fork shaped hand set performing at Korean golf courses (Ansung Benest, D; Sky72, E; Lakeside, F type), and three methods using the repair machine with 6, 8, or 14 teeth (G, H, I type, respectively). Three creeping bentgrass cultivar of 'Penncross', 'T-1', and 'CY-2' were tested in this field experiment. This test was carried out from September to November in 2009 at the nursery on the Seoul Lakeside Golf course. The average speed of turfgrass recovery after various ball mark repairing methods have been ranked as in the order of E, D, C, B, F, I, H, G, and A. The methods of hand practise showed more effective results than repair method using machines. The ball mark recovery speeds of 'Penncross' were in the order of E, D, B, C, F, I, H, and A. In the case of 'T1' and 'CY-2', similar orders were showed as D, E, B, F, C, H, I, A, G and the order of D, E, C, F, B, H, G, I, A, respectively. The ball mark recovery speed among creeping bentgrass cultivar resulted in the order of 'CY-2', 'Penncross', and 'T-1'. The most proper method of ball mark repair was repair method using a hand set tool especially the method of the Sky72 Golf course (E type). At the first, remove a damaged grass area with fork and tap. And then gather the side grasses into the center area with pulling the grasses with fork. After that, make harden and flat on the turf surface by pounding and rolling with the round wooden stick. The final Nstep, water the repaired grass surface. This ball mark repairing practise showed a most rapid and proper recovery method on creeping bentgrass green.

A Simple Method for the Monitoring of Photo-induced Alignment of the Azobenzene Molecules in a Poly(malonic ester)

  • Shin, H.D.;Hwang, U.J.;Oh, C.H.;Song, S.H.;Kim, P.S.;Han, Y.K.
    • Journal of Korean Vacuum Science & Technology
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    • v.6 no.1
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    • pp.1-4
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    • 2002
  • A simple method for real-time monitoring the molecular orientation in a polymeric film was suggested. This method was examined in the polarization holograms by two recording beams on a poly(malonic ester) containing disperse red 1. The spatial distributions of the photo-induced alignment were measured and analyzed at various polarization states of two recording beams. As the result, the directions of molecular alignments could be identified easily by our method.

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Behavior of Hydroxide Ions at the Water-Ice Surface by Low Energy Sputtering Method

  • Kim, S.Y.;Park, E.H.;Kang, H.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.338-338
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    • 2011
  • The behavior of hydroxide ions on water-ice films was studied by using $Cs^+$ reactive ion scattering (RIS), low energy sputtering (LES) and temperature-programmed desorption (TPD). A $Cs^+$ beam of a low kinetic energy (<100 eV) from $Cs^+$ ion gun was scattered at the film surface, and then $Cs^+$ projectiles pick up the neutral molecules on the surface as $Cs^+$-molecule clusters form (RIS process). In LES process, the preexisting ions on the surface are desorbed by the $Cs^+$ beam impact. The water-ice films made of a thick (>50 BL) $H_2$O layer and a thin $D_2O$ overlayer were controlled in temperatures 90~140K. We prepared hydroxide ions by using Na atoms which proceeded hydrolysis reaction either on the ice film surface or at the interface of the $H_2O$ and $D_2O$ layers.[1] The migration of hydroxide ions from the $H_2O/D_2O$ interface to the top of the film was examined as afunction of time. From this experiment, we show that hydroxide ions tend to reside at the water-ice surface. We also investigated the H/D exchange reactions of $H_2O$ and $D_2O$ molecules mediated by hydroxide ions to reveal the mechanism of migration of hydroxide to the ice surface.

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Multi-Objective Optimization Technique Using Genetic Algorithm and Its Application to Design of Linear Induction Motor (유전알고리즘을 이용한 선형유도전동기의 다중목적 최적설계)

  • Ryu, K.B.;Choi, Y.J.;Kim, C.E.;Kim, S.W.;Park, Y.C.;Kim, J.H.;Im, D.H.
    • Proceedings of the KIEE Conference
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    • 1994.07a
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    • pp.165-167
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    • 1994
  • This paper presents a new method for multiobjective optimization using Genetic Algorithm-Sexual Reproduction Model(SR model). In SR model, each individual consists of chromosome pairs. Sex cells(gametes) are produced through artificial meiosis in which crossover and mutation occur, The proposed method has two selection operators, one, individual selection which selects the individual to fertilize, and the other, gamete selection which makes zygote for offspring production, The two selection schemes are repectively conducted according to different fitness(or objective) function and consequently give a solution which is unbiased to any objectives. We apply the proposed method to optimization of the design parameters of Linear Induction Motor(LIM) and show its effectiveness.

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