• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.5
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• pp.69-74
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• 2010

In this paper, we proposed a compact arbitrary dual-band band-stop filter using CRLH transmission line. The proposed filter used CRLH transmission line as stub and it developed dual-band band-stop characteristics using non-linear phase response of CRLH transmission line. The size of proposed filter is compact. And it can control arbitrary dual stop band. In this paper, designed band-stop filter at GPS band and ISM band As result, the S(2,1) is about -30dB at GPS band and about -29dB at ISM band. The fabricated filter is very compact. Its dimension is 10mm*15mm.

• Korean Journal of Remote Sensing
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• v.27 no.5
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• pp.613-623
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• 2011

This study assessed the feasibility to apply Two-band and Three-band reflectance models for chlorophyll-a estimation in turbid productive waters whose scale is smaller and narrower than ocean using a high spatial resolution image. Those band ratio models were successfully applied to analyzing chlorophyll-a concentrations of ocean or coastal water using Moderate Imaging Spectroradiometer(MODIS), Sea-viewing Wide Field-fo-view Sensor(SeaWiFS), Medium Resolution Imaging Spectrometer(MERIS), etc. Two-band and Three-band models based on band ratio such as Red and NIR band were generally used for the Chl-a in turbid waters. Two-band modes using Red and NIR bands of RapidEye image showed no significant results with $R^2$ 0.38. To enhance a band ratio between absorption and reflection peak, We used red-edge band(710 nm) of RapidEye image for Twoband and Three-band models. Red-RE Two-band and Red-RE-NIR Three-band reflectance model (with cubic equation) for the RapidEye image provided significance performances with $R^2$ 0.66 and 0.73, respectively. Their performance showed the 'Approximate Prediction' with RPD, 1.39 and 1.29 and RMSE, 24.8, 22.4, respectively. Another three-band model with quadratic equation showed similar performances to Red-RE two-band model. The findings in this study demonstrated that Two-band and Three-band reflectance models using a red-edge band can approximately estimate chlorophyll-a concentrations in a turbid river water using high-resolution satellite image. In the distribution map of estimated Chl-a concentrations, three-band model with cubic equation showed lower values than twoband model. In the further works, quantification and correction of spectral interferences caused by suspended sediments and colored dissolved organic matters will improve the accuracy of chlorophyll-a estimation in turbid waters.

• Applied Biological Chemistry
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• v.27 no.2
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• pp.129-134
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• 1984

Change of protein component in soybean sprout grown at four temperatures was investigated by polyacrylamide gel electrophoresis. Main bands were identified using purified seed globulins. Electrophoretogram showed 5 main bands (a. b, c, d, and p) and 10 minor bands in seed and maximum number (19) of bands (8 main band including 0 and 11 minor) at 4th day after germination in cotyledon. All bands appeared in axis protein but resolution was poor. In cotyledon, a component (most rapidly) and b+c+d component decreased while o+p component and other minor components were increased at 6th day and decreased thereafter. In axis all components increased rapidly, especially in minor components and b+c+d component. High growing temperature accelerated decrease in cotyledon and increase in axis of protein, especially for 11S. The a component was identified as 7S, b+c+d as 11S and o+p as 2S globulin.

• ETRI Journal
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• v.23 no.1
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• pp.1-8
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• 2001

The performance of a long wavelength-band erbium-doped fiber amplifier (L-band EDFA) using 1530nm-band pumping has been studied. A 1530nm-band pump source is built using a tunable light source and two C-band EDFAs in cascaded configuration, which is able to deliver a maximum output power of 23dBm. Gain coefficient and noise figure (NF) of the L-band EDFA are measured for pump wavelengths between 1530nm and 1560nm. The gain coefficient with a 1545nm pump is more than twice as large as with a 1480nm pump. It indicates that the L-band EDFA consumes low power. The noise figure of 1530nm pump is 6.36dB at worst, which is 0.75dB higher than that of 1480nm pumped EDFA. The optimum pump wavelength range to obtain high gain and low NF in the 1530nm band appears to be between 1530nm and 1540nm. Gain spectra as a function of a pump wavelength have bandwidth of more than 10nm so that a broadband pump source can be used as 1530nm-band pump. The L-band EDFA is also tested for WDM signals. Flat Gain bandwidth is 32nm from 1571.5 to 1603.5nm within 1dB excursion at input signal of -10dBm/ch. These results demonstrate that 1530nm-band pump can be used as a new efficient pump source for L-band EDFAs.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.8 no.1
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• pp.18-23
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• 2009

The conventional channel selection method for a ZigBee communication network basically detects the energy values in all channels. In the ISM band, no license is required to use channels in this band, so there may exist various interference factors in this band. It is well known that WLAN is the major interference factor degrading the performance of ZigBee in the ISM band. In this paper, we propose an efficient channel selection algorithm which uses the pattern of two types of WLAN channel uses as the a priori information of IEEE 802.11 band IEEE 802.11g. By using the proposed algorithm, we may save the time required to select channels for the ZigBee communications.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.5
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• pp.784-792
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• 1990

In this paper, attempts have been made to compare the subjective performance of sub-band coding (SBC) techniques incorporating four representative modulation transfer functions (MTF's) of th human visual system(HVS): Sakrison, Nill, Ngan, and Rao. In SBC, the frequency band of input signal is split into 16 equal sub-bands. In addition, 28 sub-band splitting schemd which splits more sub-bands in low spatial frequency is considered to compare the 4 MTF's effectively. In encoding of each sub-band, the weight of each sub-band obtained from the MTF of HVS is applied to bit allocation process which minimize the weighted mean square error (WMSE). The differential pulse code modulation(DPCM) coder is used to encode the lowest sub-band and the pulse code modulation(PCM) coder is used for the rest of sub-bands. It is found that the images incorporating the MTF of Rao yields the best results in subjective criteria, followed by Ngan, Nill, Sakrison, and the images not employing the HVS.

• Advances in nano research
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• v.9 no.2
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• pp.105-112
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• 2020

Silicene is a two-dimensional (2D) derivative of silicon (Si) arranged in honeycomb lattice. It is predicted to be compatible with the present fabrication technology. However, its gapless properties (neglecting the spin-orbiting effect) hinders its application as digital switching devices. Thus, a suitable band gap engineering technique is required. In the present work, the band structure and density of states of uniformly doped silicene are obtained using the nearest neighbour tight-binding (NNTB) model. The results show that uniform substitutional doping using aluminium (Al) has successfully induced band gap in silicene. The band structures of the presented model are in good agreement with published results in terms of the valence band and conduction band. The band gap values extracted from the presented models are 0.39 eV and 0.78 eV for uniformly doped silicene with Al at the doping concentration of 12.5% and 25% respectively. The results show that the engineered band gap values are within the range for electronic switching applications. The conclusions of this study envisage that the uniformly doped silicene with Al can be further explored and applied in the future nanoelectronic devices.

• Journal of Satellite, Information and Communications
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• v.8 no.3
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• pp.47-51
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• 2013

In this paper, we present design and test results of a Ka-band dual-band ortho-mode transducer (OMT) for use in a feed assembly for the very small aperture terminals (VSATs). The designed ortho-mode transducer have wideband characteristics to separate the signals that have two orthogonal linear polarizations operating at 20GHz of receive frequency band and at 30GHz of transmit frequency band. In addition, in order to reduce the volume of the feed assebly, a Boifot based ortho-mode transducer has been designed with a dual-band. Experimental results for the design verification, the return loss in the receive band and in the transmit band for the horizontal polarization showed over 20dB and 21dB, respectively, and for the vertical polarization showed over 20dB and 24dB, respectively. The port isolation for the horizontal polarization and the vertical polarization showed over 43dB and 52dB, respectively, in the receive band and in the vertical band.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.385-386
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• 2008

In this paper, a simple dual band filter chip is designed with 0603 case size using IPD technology. The dual-band filter achieves high frequency band at 2.5 GHz and low frequency band at 1.8 GHz. The insertion losses in high frequency band and low frequency band are -0.195 dB and -0.146 dB, respectively. The return losses in these bands are -22.7 dB and -22.8 dB, respectively. The simple dual-band filter based on SI-GaAs substrate is designed within die size of about 1.3 $mm^2$.

• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.101-104
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• 2001

In this paper, we have analyzed algorithm about physical layer, data link layer and MAC layer of out-of-band specified in the DVS 178 and designed architecture of Out-of-band processor. Out-of-band processor extracts session key information from EMM packet to descramble MPEG-2 TS packet scrambled. Also, analyze EAS Packet including emergency alert information to provide emergency communications such as national emergency. In this paper, we have implemented prototype board for out-of-band processor.