• Transactions of the Korean hydrogen and new energy society
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• v.13 no.3
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• pp.169-180
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• 2002

Rayleigh scattering and laser induced predissociative fluorescence are used to obtain two-dimensional images of temperature and species concentration in a laminar non-premixed flame of a diluted hydrogen jet. Rayleigh scattering cross-sections are experimentally obtained at 248nm. Planar images of OH and $O_2$ with tunable KrF excimer laser which has a) $0.5cm^{-1}$ linewidth, b) 0.5nm tuning range, c) 150mJ pulse energy, and d) 20ns pulse width are obtained to determine spatial distributions of OH and $O_2$. The technique is based on planar laser induced predissociative fluorescence (PLIPF) in which collisional quenching is almost avoided because of the fast predissociation. Dispersed LIPF spectra of OH and $O_2$ are also measured in a flame in order to confirm the excitation of single vibronic state of OH and $O_2$. OH and $O_2$ are excited on the $P_2$(8) and $Q_1$(11) line of the $A^2{\Sigma}^{+}({\nu}^{'}=3)-X^{2}{\Pi}({\nu}^{''}=o)$ band and R(17) line of the Schumann-Runge band $B^{3}{\Sigma}_{u}{^-}(\nu^{'}=0)-X^{3}{\Sigma}_{g}{^-}({\nu}^{''}=6)$, respectively. Fluorescence spectra of OH and Hot $O_2$ are captured and two-dimensional images of the hydrogen flame field are successfully visualized.

• The Korean Journal of Nuclear Medicine
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• v.33 no.6
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• pp.475-483
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• 1999

Purpose: Complete fibrovascular ingrowth within the hydroxyapatite ocular implant is necessary for peg drilling which is performed to Prevent infection and to provide motility to the ocular prosthesis. We compared planar bone scintigraphy and SPECT for the evaluation of the vascularization within hydroxyapatite ocular implants. Materials and Methods: Seventeen patients (M:F: 12:5, mean age; $50.4{\pm}17.5$ years) who had received a coralline hydroxyapatite ocular implant after enucleation surgery were enrolled. Patients underwent Tc-99m MDP planar bone and SPECT imaging by dual head gamma camera after their implant surgery (interval: $197{\pm}81$ days). Uptake on planar and SPECT images was graded visually as less than (grade 1), equal to (grade 2), and greater than (grade 3) nasal bridge activity. Quantitative ratio of implanted to non-implanted intraorbital activity was also measured. Vascularization within hydroxyapatite implants was confirmed by slit lamp examination and ocular movement. Results: All but three patients were considered to be vascularized within hydroxyapatite implants. In visual analysis of planar image and SPECT, grade 1 was noted in 9/18 (50%) and 6/18 (33%), respectively. Grade 2 pattern was 7/18 (39%) and 4/18 (22%), and grade 3 pattern was 2/18 (11%) and 8/18 (44%) respectively. When grade 2 or 3 was considered to be positive for vascularization, the sensitivity of planar and SPECT imaging were 60% (9/15) and 80% (12/15), respectively. In 3 patients with incomplete vascularization, both planar and SPECT showed grade 1 uptake The orbital activity ratios on planar imaging were not significantly different between complete and incomplete vascularization ($1.96{\pm}0.87$ vs $1.17{\pm}0.08$, p>0.05), however, it was significantly higher on SPECT in patients with complete vascularization ($8.44{\pm}5.45$ vs $2.20{\pm}0.87$, p<0.05). Conclusion: In the assessment of fibrovascular ingrowth within ocular implants by Tc-99m MDP bone scintigraphy, SPECT image appears to be more effective than planar scintigraphy.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.3
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• pp.115-121
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• 2001

In micro automation technology, the concurrent realization of a high resolution and a large operating rage has been achieved by a dual actuator, usually called by piggy-back system, conventionally. But, because of its manufacturing cost, the complexity of control, and the limit of overall bandwidth, the contract-free and single servo actuators have been suggested with specific applications. In this paper, we suggest a novel non-contact surface actuator suing combination of the Lorentz force and the magnetized force, and discuss the actuating principles including an analytical approach. Differently from the existing planar system, an operating range of the suggested system can be expanded by an additional attachment of active elements. Therefore, it is estimated to be suitable for the next-generation moving system.

• Bulletin of the Korean Chemical Society
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• v.17 no.4
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• pp.331-334
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• 1996

New copper(Ⅱ) complex of the pentaaza non-macrocyclic ligand 1-(2-aminoethyl)-3-(N-{2-aminoethyl}aminomethyl)-1,3-diazacyclohexane (2) and a dinuclear copper(Ⅱ) compex of the bis(macrocyclic) ligand 3, in which two 1,5,8,10,12,15-hexaazabicyclo[11.3.11.5]heptadecane subunits are linked together by an ethylene chain through the uncoordinated nitrogen (N10) atoms, have been prepared selectively by the reaction of the metal ion, 1,4,8-triazaoctane, ethylenediamine, and formaldehyde. The dinuclear complex [Cu2(3)]4+ has been also prepared by the reaction of [Cu(2)]2+ with ethylenediamine and formaldehyde. The reaction products largely depend on the molar ratio of the reactants employed. The mononuclear complex or each macrocyclic subunit of the dinuclear complex contains one 1,3-diazacyclohexane ring and has a square-planar geometry with a 5-6-5 or 5-6-5-6 chelate ring sequence. In acidic solution, the copper(Ⅱ) complex of 2 dissociates more slowly than those of other related non-cyclic polyamines.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.451-454
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• 1999

An existing plasticity model using multiple failure criteria is modified to describe the behavior of reinforced concrete planar members under cyclic load. Multiple failure criteria are used to define both isotropic damage of compressive crushing and anisotropic damage of tensile cracking. A numerical method is developed to define multi-directional and non-orthogonal crack directions. The material model is implemented in the finite element analysis and verified by comparison with existing experiments of reinforced concrete shear wall.

• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.6
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• pp.635-644
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• 2003

To ensure the reliability of ultrasonic nondestructive testing techniques for modern structural materials, the effects of anisotropy and inhomogeneity and the influence of non-planar component geometries on ultrasonic wave propagation have to be taken into account. In this article, fundamentals and applications of two analytical approaches to three-dimensional elastic beam field calculation are presented. Results for both isotropic materials including curved interfaces and for anisotropic media like composites are presented, covering field profiles for various types of transducers and the modeling of time-dependent rf-signals.

• Proceedings of the Korean Vacuum Society Conference
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• 2005.02a
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• pp.78-78
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• 2005

• 제어로봇시스템학회:학술대회논문집
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• 1988.10a
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• pp.125-130
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• 1988

This study presents a method to determine the ground reation forces of a quadruped walking machine on its foot ends caused by the body weight and the inertia forces from the commanded acceleration. The method shows the same result as the Pseudo-Inverse Method when the 4 feet stand on a plane. However method can be applied even when the 4 feet stand on a non-planar surface for which, no feasible solution can be obtained by the Pesudo-Inverse Method.

• Journal of Mechanical Science and Technology
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• v.19 no.8
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• pp.1649-1661
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• 2005

We consider. a horizontal static liquid layer on a planar solid boundary. The layer is evaporating when the plate is heated. Vapor recoil and thermo-capillary are discussed along with the effect of mass loss and vapor convection due to evaporating liquid and non-equilibrium thermodynamic effects. These coupled systems of equations are reduced to a single evolution equation for the local thickness of the liquid layer by using a long-wave asymptotics. The partial differential equation is solved numerically.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.29B no.1
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• pp.67-75
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• 1992

A new method of driving the PDP(Plasma Display Panel) was proposed and its characteristics were investigated. Applying high frequency non-discharge pulses to an auxiliary anode resulted an increased region of stable operation, decreased delay time and increased light intensity. It is suggested that PDP with DPM (Double Pulse Memory) drive technique improves the delay time, luminance, region of stable operation and luminous efficacy compared to PDP with PPM(Planar Pulse Memory) drive technique developed by NHK Lab. in Japan.