• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 2002.11a
• /
• pp.241-245
• /
• 2002

Dual-band microstrip antenna is designed for industrial-scientific-medical(ISM) band of 2.4㎓ and 5.8㎓ using finite-difference time-domain method(FDTD). Cross Patch fed by aperture in the ground plane of microstrip line is proposed as radiation element of antenna, which is 2 rectangular Patch is overlapped. To design antenna, change of input impedance by aperture and stub length change is examined. And it is investigated that center frequency and -10 ㏈ bandwidth by Length of radiation element and width change. Experimental result about reflection Loss confirmed that agree well with analysis results of FDTD and IE3D, And -3 ㏈ beam width, front to back ratio and gain in frequency 2.43㎓ and 5.79㎓ is presented by measuring radiation Pattern of antenna.

• Journal of Plant Biology
• /
• v.38 no.2
• /
• pp.159-164
• /
• 1995

The taxonomic note was given to the species of Ceramium from Ullungdo Island. Five species, Ceramium aduncum Nakamura, C. codii (Rhichards) G. Mazoyer, C. flaccidum (Harvey exK tzing) Ardissone, C. paniculatum Okamura, and C. tenerrimum (Martense) Okamura were collected during this study. C. aduncum was collected in the intertidal and upper subtidal zones from December to Feburary. They had a narrow internodal space showing 1/3-1/5 times as large as nodal band. C. codii had the spermatangial mother cells developed on abaxial cortical cells of cortical band C. paniculatum collected in summer and winter had a creeping thallus and alternative branching type in gross morphology. The axial cell of C. flaccidum showed 2.3-2.8 L/B ratio, smaller than those of plants from Chejudo Island.

• Proceedings of the Korea Society of Poultry Science Conference
• /
• 2000.11a
• /
• pp.85-87
• /
• 2000

To obtain the genetic information of Korean native livestock, the karyotyping of Korean native chick were performed by high-resolution banding technique. The chromosomes were prepared from lymphocyte culture and early embryos with 200 Korean native chick which have been raised at National Livestock Research Institute. There were no significant difference between Korean native chick and Leghorn in the number of chromosomes and chromosomal morphological pattern. Using high resolution banding technique, the yield of G-bands of prophase is much greater than that can be obtained by International System for Standardzed Avian Karyotypes(ISSAK, 1999). The G-band landmarks of Korean native chick were similar to those of ISSAK and Leghorn except some macrochromosomes. chromosome Z and 3 had C-band variants with heteromorphic patterns on distal and centromeric site. The proportion of constitutive heterochromatin, the heterochromatin ratio of Korean native chick was significantly more than that of Leghorn in all chromosomes.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.7 no.8
• /
• pp.132-142
• /
• 1999

In this paper, a new formula for primary and secondary thrust of metal belt CVT is proposed considering variation of band tension, block compression and active arc for each of the primary and secondary pulleys. For the secondary thrust, effective friction coefficient is introduced considering the effect of flange deflection. Nondimensional primary and secondary thrust of the metal belt CVT by the new formula agree well with the experimental results except for low torque range, $0\;<\;{\lambda}\;<\;0.2$ at speed ration i = 1.0. The new formula can be used in design of the primary and secondary thrusts control system for the metal belt CVT.

• Journal of Electrical Engineering and Technology
• /
• v.12 no.3
• /
• pp.1250-1256
• /
• 2017

This paper proposes the design of microstrip patch antennas for dual-band polarization adjustment. The antenna has a multi-layer structure for dual-band operation, and each layer contains a resonating patch with surrounding strips separated into two parts. The antenna polarization is adjusted by varying the separated positions of the strips, while fixing other design parameters. To demonstrate the feasibility, an antenna sample with right-hand circular polarization is fabricated, and its antenna characteristics are measured in a full anechoic chamber. The operating principle of polarization adjustment in the dual frequency bands is also verified by observing near electromagnetic fields and the magnetic surface current density around the antenna.

• Journal of the Korean Graphic Arts Communication Society
• /
• v.18 no.2
• /
• pp.1-12
• /
• 2000

This paper proposes a new algorithm classifing same hues in order toe estimate the spectral reflectance of object from 3 band color image information. To estimate the spectral reflectance of object, the conventional estimation methods are required of 5 or 9 band digital color values. The 5 or 9 band image acquisition systems are required of 5 or 3 times same work for color image acquisition process. To solve the above problems, we propose a new method that can be estimated spectra reflectance estimation of object. The proposed method is to classify same hues corresponding a color stimulus, by using hue angle and chroma vector of a color stimulus. The classified same hues are used as the population corresponding a color stimulus. The range of same hue is estimated by the cumulative proportional ration according to the number of basis function.

• Journal of Satellite, Information and Communications
• /
• v.1 no.1
• /
• pp.1-4
• /
• 2006

Ku band satellite signal repeating technology just altering a polarization of the repeated signal is applicable for any kind of satellite broadcasting service in geographically shadowed area due to high-rise buildings, trees, and so on. This paper focuses on the design of high polarization discrimination antenna satisfying polarization characteristics with respect to field pattern and frequency band. Designed antenna for the enhancement of axial ratio and polarization discrimination characteristic shows good performance for satellite broadcasting service repeating system.

• Bulletin of the Korean Chemical Society
• /
• v.8 no.2
• /
• pp.115-118
• /
• 1987

The angular dependence of polarization of the A-band emission from RbCl:$Pb^{2+}$ is measured at 13.4 K to determine the symmetry axes of the $Pb^{2+}-v^-_c$ dipoles. The results indicate that these centers posess tetragonal symmetry. This implies that $v^-_c$ is situated in the next-nearest-neighbor (nnn) position to the $Pb^{2+}$ ion. The polarization ratio of the A-band emission measured at various temperatures is found to be independent of the temperature. The temperature independence of polarization confirms that, for the ion, the Jahn-Teller effect reduced by strong spin-orbit interaction does not give rise to thermal depolarization.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.18 no.1
• /
• pp.32-41
• /
• 2014

Currently, the three major Korean mobile operators hold a total of 390MHz of bandwidth, but at the current data traffic increase of almost 6 times per year, more frequency bandwidth should be secured in order to meet the exploding data traffic in the future. It is believed that 2.1GHz frequency band is suitable for mobile communication in the light of frequency characteristics and continuity of the band. In this paper, we perform compliance analysis with the international radio regulation for coexistence with the adjacent region in order to use 2.1GHz band for LTE-Advanced. In addition, we verify that 2.1GHz band can coexist with the adjacent band by conducting an interference evaluation.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2007.04a
• /
• pp.440-443
• /
• 2007

In this paper, microstrip antenna is designed for industrial-scientific-medical(ISM)band of S-Band. We proposed that radiation element of antenna, which is rectangle patch shape. The feeding structure used L-shaped structure. Center frequency and -l0dB bandwidth are investigated by change of length and width in patch plane. And maximum gain, front to back ratio and 3dB beam width is presented by simulation radiation pattern of antenna in frequency ISM Band. The center frequency is 2.45GHz, band width is $2.314{\sim}2.577GHz$ with 263MHz(11%). And the antenna maximum gain is 9.3dBi, 3dB beam width E-plane is $52.5^{\circ}$, H-plane is $64.7^{\circ}$.