• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1623_1624
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• 2009

The use of arc tubes made of ceramic material further enhanced some of the metal halide lamp’s properties. These properties translate into higher efficacy with better color rendering, stable color through lamp long life. Recently, due to an increase in the application of the ceramic metal-halide lamp, the study for the property etc. according to Ballast's driving scheme and the study for arc tube material, optimization of gas and so on are being proceeded to improve the property of the lamp. Especially, to control ceramic metal-halide lamp, the vigorous study and practical use with respect to Electronic Ballast, which has been improved in the disadvantages of the conventional Magnetic Ballast are made. In this paper, Electrical characteristics and gas insulation destroy time are analyzed by comparing magnetic ballast with electronic ballast.

• Nuclear Engineering and Technology
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• v.3 no.4
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• pp.198-202
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• 1971

Kinetic studies on the halide exchange reactions of some substituted benzyl chlorides have been carried out using radioisotope tracer halide ions. Results are consistent with our previous conclusion that the rates of halide exchange reactions in acetone with arylmethy halides are dictated by the porarizabilities of both substrate and nucleophile.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1495-1496
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• 2008

The Ceramic Metal Halide lamp is different from optical characteristic on shapes of arc-tube and driving method of ballast. In this paper, we measured optical characteristics of the Ceramic Metal Halide lamp that uses arc tubes which are spherical and cylindrical shapes, and analyzed the Ceramic Metal Halide lamp connecting ballast that is electronic and magnetic types through the lamp measurement system that is given for stabilization period of fifteen minutes. In result, the arc-tube of spherical shape is more improvement in the optical properties than the arc tube of cylindrical shape, moreover, the electronic ballast is more efficient than the optical properties of the magnetic ballast.

• Nuclear Engineering and Technology
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• v.5 no.1
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• pp.20-25
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• 1973

Kinetics of halogen exchange reactions of phenacyl halides using radioisotope tracer halide ions in anhydrous acetone have been studied. The reactions wore believed to be SN2 processes and the orders of relative nucleophilicity of halide ions were Cl->I->Br- for the phenacyl chloride and I->Cl->Br- for the phenacyl bromide. These were interpreted in terms of solvation effect of halide ions and HSAB principle.

• Journal of the Korean Chemical Society
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• v.34 no.6
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• pp.658-662
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• 1990

A method for regioselective mono-carbonylation of halobenzyl halide is described. Alkyl halophenylacetate is easily prepared by carbonylating a benzylic halide of halobenzyl halide in the presence of catalytic amount of cobalt carbonyl, a base, and an alcohol under atmospheric pressure of carbon monoxide. The base plays a decisive role in the selectivity of product and NEt$_3$ is the best one among bases used.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.9
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• pp.1-7
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• 2010

Ceramic metal halide lamps have been widely used due to long lifetime, high luminous efficiency and good colour rendering. 35[W] ceramic metal halide lamps has very different characteristics between ignition state and steady state. The developed electronic ballast is satisfied to both ignition state and steady state characteristics by using a micro-controller. The proposed electronic ballast is consists of EMI filter, Full-wave rectifier, Active PFC, DBI(Dual Buck Inverter), Igniter and control circuit. It enables to supply both low-frequency rectangular wave voltage and current to the lamp by using DBI(Dual Bcuk Inverter) structure.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.12
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• pp.2238-2243
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• 2008

The use of arc tubes made of ceramic material further enhanced some of the metal halide lamp's properties. These properties translate into higher efficacy with better color rendering, stable color through lamp long life. Recently, due to an increase in the application of the ceramic metal-halide lamp, the study for the property etc. according to Ballast's driving scheme and the study for arc tube material, optimization of gas and so on are being proceeded to improve the property of the lamp. Especially, to control ceramic metal-halide lamp, the vigorous study and practical use with respect to Electronic Ballast, which has been improved in the disadvantages of the conventional Magnetic Ballast are made. In this paper, Electrical, optical and thermal characteristics are analyzed by comparing magnetic ballast with electronic ballast.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.12
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• pp.2244-2248
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• 2008

High intensity metal halide discharge lamp performance, specifically the generated luminous flux and light color content, depends critically on the arc tube design. Factors influencing the design and consequent lamp efficacy include : lamp size, geometry, arc tube composition, fill chemistry, electrode design and excitation modes. Shaping of Polycrystalline Alumina(PCA) can be realized by conventional ceramic processes. Several processes are applied nowadays. Well-known in the ceramic high pressure field for decades are the pressing and the extrusion method. Newly developed slurry and precious forming technologies give the one-body seamless tubes, which improve thickness uniformity and lighting performance. Now, we reported some optical properties with different arc tube structures of ceramic metal halide lamps.

• Proceedings of the KIEE Conference
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• 2001.10a
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• pp.208-211
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• 2001

This paper presents the considerations of the high frequency modulation method for the metal halide lamp electronic ballast. The acousitc resonance phenomenon is occurred, if the metal halide lamp is driven at constant high frequency. The frequency modulation method therefore, is used to avoid the acoustic resonance phenomenon, but the crest factor of lamp current is increased. In this paper, the driving characteristic of the metal halide lamp according to the waveshape and frequency variations of modulating signal is considered with a viewpoint of crest factor.

• Journal of the Korean Chemical Society
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• v.68 no.2
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• pp.65-73
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• 2024

The halide-acetylene anions, X^--HCCH (X = F, Cl, and Br) have been studied by using several different ab initio and DFT methods to determine structures, hydrogen-bond energies, vibrational frequencies of the anion complexes. Although the halide-acetylene complexes all have linear equilibrium structures, it is found that the fluoride complex is characterized with distinctively different structure and interactions compared to those of the chloride and bromide complexes. The performance of various density functionals on describing ionic hydrogen-bonded complexes is assessed by examining statistical deviations with respect to high level ab initio CCSD(T) results as reference. The density functionals employed in the present work show considerably varying degrees of performance depending on the properties computed. The performances of each density functional on geometrical parameters related with the hydrogen bond, hydrogen-bond energies, and scaled harmonic frequencies of the anion complexes are examined and discussed based on the statistical deviations.