• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.5
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• pp.652-659
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• 2012

Shielding effectiveness(SE) of metallic rectangular enclosure with rectangular slit apertures at horizontal polarization (HP) and vertical polarization(VP) is investigated. The magnetic polarizability of the rectangular slit apertures and the resonance modes of the metallic rectangular enclosure are analyzed theoretically. The simulation results based on these theoretical analyses are compared with the measured ones. The dependence of the shielding effectiveness on the location of the calculation probe inside the enclosure is also investigated.

• Journal of the Korean Chemical Society
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• v.24 no.4
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• pp.269-279
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• 1980

A method for calulation of the magnetic moments for both octahedral and distorted octahedral $[V(III)A_3B_3]$ type complexes, all with $t^2_2$ configuration, has been developed [A and B = O, Cl, N, F or Br]. The calculated magnetic moments by this method are in reasonable agreements with the experimental values. The calculated magnetic moments for distorted octahedral $[V(III)A_3B_3]$/TEX> type complexes decrease as the extent of tetragonal distortion increases.The effects of k (orbital reduction faction factor), $\xi'$/TEX> and temperature on the magnetic moments are also investigated.A new method for calculation of the contribution of $^3T_1$ molecular orbitals to the dipole moment and polarizability has also developed. The calculated contribution of $^3T_1$ molecular orbitals falls in the reasonable range of values.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.5 no.1
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• pp.31-39
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• 1991

The polarization properties of low birefringent optical fiber due to intrinsie birefringence and magnetooptic effects are theoretically analyzed and experimented. The low birefringent fiber is fo¬und to have more excellent polarization maintaining properties than normal single mode optical fiber. As the experimental results, the polarizability of low birefringent optical fiber is measured over 0.818. The variation of output polarization angle with input polarization angle is measured within $9^{\circ}$. Imple¬mented magnetic field measuring system using low birefringent optical fiber can linearly measure the magnetic field strength up to lOkAT generated by solenoid. The maximum error is 1.95% in the magnetic field strength of 4kAT.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.11
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• pp.70-77
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• 1996

In this paper, a modifed TE$_{113}$/TM$_{012}$ triple-mode bandpass filter is implemented by using a modified inter-cavity iris in which the number of slots are reduced upto 50%. In a coventioanl iris two prirs of slot apertures are used to independently couple three resonant modes between two adjacent cavities. However, if transverse magnetic polarizability of a pair of veritcal slot apertures is used to control weak horizontal TE$_{h}$-TE$_{h}$ mode coupling, the width of novel iris slots would substitute for the slot length of the conventional iris, causing to eliminate the horizontal slot apertures. The measured data of two filters, which are the modified filter and ocnventional one, are compared. Experimental result shows that the characteristics of the novel triple-mode filter matches well that of the conventional filter.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.8
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• pp.7-15
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• 1994

In this paper, the directional coupler for Ku-band, which is designed is of the crossguide type with a coupling value of about 3-dB. The apertures chosen for this design are crosses. We used polynomial approximations of rounded end slot to obtain the electric and magnetic polarizability of crossed-slot and compared the results with Cohn's experimental results. The optimized dimensions and positions of the cross aperture are obtained by a trial-and-error reiteration of the program. This paper presents the measurement results for the designed coupler. The very flat coupling shows a total variation of only 29.80$\pm$0.04dB for the design frequency ranges of 12.25GHz-12.75GHz. The measured minimum directivity is 25dB. The aperture attenuation for the finite diaphragm thickness is about 2dB pr 0.5mm, which is in agreement with the theoretical value. The transmission loss and input return loss at center frequency are 0.0564dB and 48.16dB respectively. We obtained the measured minimum directivity of the coupler. Whose apertures are both circles is better than that containing holes in the performance of directivity.

• Korean Journal of Materials Research
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• v.20 no.7
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• pp.370-373
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• 2010

In fabricating plasma display panels, the photolithographic process is used to form patterns of barrier ribs with high accuracy and high aspect ratio. It is important in the photolithographic process to control the refractive index of the photosensitive paste. The composition of this paste for photolithography is based on the $B_2O_3-SiO_2-Al_2O_3$ glass system, including additives of alkali oxides and rare earth oxides. In this work, we investigated the density, structure and refractive index of glasses based on the $B_2O_3-SiO_2-Al_2O_3$ system with the addition of $Li_2O$, $K_2O$, $Na_2O$, CaO, SrO, and MgO. The refractive index of the glasses containing K2O, Na2O and CaO was similar to that of the [BO3] fraction while that of the SrO, MgO and Li2O containing glasses were not correlated with the coordination fraction. The coordination number of the boron atoms was measured by MAS NMR. The refractive index increased with a decrease of molar volume due to the increase in the number of non-bridging oxygen atoms and the polarizability. The lowest refractive index (1.485) in this study was that of the $B_2O_3-SiO_2-Al_2O_3-K_2O$ glass system due to the larger ionic radius of $K^+$. Based on our results, it has been determined that the refractive index of the $B_2O_3-SiO_2-Al_2O_3$ system should be controlled by the addition of alkali oxides and alkali earth oxides for proper formation of the photosensitive paste.