• Journal of electromagnetic engineering and science
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• v.17 no.3
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• pp.159-164
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• 2017

This article proposes a design of chipless RFID tag with dipole array structure that is fully printable using conductive ink. The proposed tags encode data based on spectral signature modulations. The reading range is considerably increased (2 m) while maintaining low transmission power (1 mW). Several prototype chipless RFID tags were fabricated and measured in the SHF and UHF bands. The proposed dipole array structure enhances the antenna gain of the passive tags and contributes to overcoming the low conductivity of conductive ink. In order to verify the utility of our proposal, the tags are manufactured on paper, using conductive ink, for the purpose of economic mass production.

• Journal of the Korean earth science society
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• v.26 no.2
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• pp.160-165
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• 2005

A series of high resolution spectra of CH Cygni obtained at the Bohyunsan Optical Astronomy Observatory (BOAO) in April 2004 has been analyzed. The emission components of the [O I] 6300 A lines are de-convoluted and fitted with Gaussian functions in order to investigate the characteristics and the structure of CH Cygni system along with the analysis for $H{\alpha}$ and [O III] lines. A present geometrical structure of the components of CH Cygni system is suggested.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.54.3-55
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• 2016

We model the spectral energy distribution (SED) of the Class 0 protostar L1527 IRS using a dust continuum radiative transfer code RADMC-3D to study the initial condition of gravitational collapse. To constrain the envelope structure, we use the data obtained by Herschel /PACS, which covers the far-infrared regime ($55-190{\mu}m$) where the SED of L1527 IRS peaks. According to our modeling, a more flattened density profile fits the far-infrared SED of L1527 IRS better than the density profile of a rotating and infalling envelope. Thus, we employ the density structure of a Bonnor-Ebert sphere, which consists of the inner flat-topped and the outer power-law regions and is often used for describing the density structure of the youngest sources in the low mass star formation process. A Bonnor-Ebert sphere fits very well the observed SED at ${\lambda}$ > $10{\mu}m$, suggesting that L1527 IRS might collapse from an unstable Bonnor-Ebert sphere rather than a singular isothermal sphere.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.12
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• pp.1725-1729
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• 2013

In this paper, the modeling and simulation of infrared absorption in an infrared absorbing structure with the cascaded transmission line model were carried out. Each layer in the infrared absorbing structure can be modeled as a characteristic impedance of the cascaded transmission line model. The simulation results show that the cavity thickness to get a maximum absorption should be less than a quarter wavelength, which is somewhat different from prevalent thickness. It can be assured that the sheet resistance of an absorbing layer to get a maximum absorption is $377{\Omega}/{\square}$, that the thickness of the absorbing layer dose not affect the spectral characteristics of absorption. It is also shown that the thickness of the active layer is not critical to the IR absorption. It can also be assured that the validation of this modeling is proved in comparison with the previous results from similar absorbing structures.

• Structural Engineering and Mechanics
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• v.8 no.1
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• pp.53-72
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• 1999

The most important features of linear soil-foundation-structure interaction are reviewed, using stochastic modeling and considering kinematic interaction, inertial interaction, and structural distortion as three separate stages of the dynamic response to the free-field motion. The way in which each of the three dynamic stages modifies the spectral density of the motion is studied, with the emphasis being on interpretation of these results, rather than on the development of new analysis techniques. Structural distortion and inertial interaction analysis are shown to be precisely modeled as linear filtering operations. Kinematic interaction, though, is more complicated, even though it has a filter-like effect on the frequency content of the motion.

• Nuclear Engineering and Technology
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• v.34 no.3
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• pp.202-210
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• 2002

The details of the electronic structure of the perfect crystal provides a critically important foundation for understanding the various defect states in uranium dioxide. In order to understand the local defect and impurity mechanism, the calculation of electronic structure of UO$_2$ in the one-electron approximation was carried out, using a semi-empirical tight-binding formalism(LCAO) with and without f-orbitals. The energy band, local and total density of states for both spin states are calculated from the spectral representation of Green’s function. The bonding mechanism in Perfect lattice of UO$_2$ is discussed based upon the calculations of band structure, local and total density of states.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.8
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• pp.1740-1746
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• 1997

In this paper, a waveguide-fed slot-coupled microstrip antenna is proposed as enhanced feeding structure of microstrip antenna and an analysis is presented. The presence of dielectric substrate between a stripand a slot is explicitly taken into account in this analysis. The evaluation of the antenna characteristics is carried out using the method of mements and the spectral domain approach in terms of the electric current distribution on the strip and the magnetic current distribution on the slot. From the results, we can conclude that the proposed structure is adequate for array antennas, due to ease of mass porduction and enhanced anteena performance.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1640-1644
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• 2011

Water-soluble mutant of intrinsically insoluble protein, crambin, was produced by mutagenesis based on the sequence analysis with homologous proteins. Thr1, Phe13, and Lys33 of crambin were substituted for Lys, Tyr, and Lys, respectively. The resultant mutant was soluble in aqueous buffer as well as in dodecylphosphocholine (DPC) micelle solution. The $^1H-^{15}N$ spectrum of the mutant crambin showed spectral similarity to that of the wild-type protein except for local regions proximal to the sites of mutation. Solution structure of water-soluble mutant crambin was determined in aqueous buffer by NMR spectroscopy. The structure was almost identical to the wild-type structure determined in non-aqueous solvent. Subtle difference in structure was very local and related to the change of the intra- and inter-protein hydrophobic interaction of crambin. The structural details for the enhanced solubility of crambin in aqueous solvent by the mutation were provided and discussed.

• Earthquakes and Structures
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• v.2 no.3
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• pp.257-277
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• 2011

An evaluation is presented of the response of a 3-storey R/C structure during the destructive Lefkada earthquake of 14/08/2003. Key aspects of the event include: (1) the unusually strong levels of ground motion (PGA = 0.48 g, $SA_{max}$ = 2.2 g) recorded approximately 10 km from fault, in downtown Lefkada; (2) the surprisingly low structural damage in the area; (3) the very soft soil conditions ($V_{s,max}$ = 150 m/s). Structural, geotechnical and seismological aspects of the earthquake are discussed. The study focuses on a 3-storey building, an elongated structure of rectangular plan supported on strip footings, that suffered severe column damage in the longitudinal direction, yet minor damage in the transverse one. Detailed spectral and time-history analyses highlight the interplay of soil, foundation and superstructure in modifying seismic demand in the two orthogonal directions of the building. It is shown that soil-structure interaction may affect inelastic seismic response and alter the dynamic behavior even for relatively flexible systems such as the structure at hand.

• Sleep Medicine and Psychophysiology
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• v.15 no.2
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• pp.71-76
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• 2008

Introduction: In this study, we compared sleep structure, EEG characteristic of pediatric obstructive sleep apnea (OSA) and normal controls which were matched in sex and age. Methods: Fifteen children (male：female=4：11) who complained snoring and were suspected to have sleep apnea and their age and sex matched normal controls (male：female=5：10) have been done nocturnal polysomnography (NPSG). Sleep parameters, sleep apnea variables and relative spectral components of EEG from NPSG have been compared between both groups. Results: Pediatric OSA group were distinguished from normal controls in terms of apnea index, respiratory disturbance index and nadir of oxyhemoglobulin desaturation. Pediatric OSA group showed increased percent of sleep stage 1, decreased rapid eye movement sleep percent and increased delta power in O1 EEG channel. However other sleep parameters and spectral powers were not different between two groups. Conclusion: In pediatric OSA group, sleep structure parameter disruption may be not prominent as the previous studies for adult OSA group because of including mild OSA data in diagnostic criteria. In addition, EEG changes might not be distinct due to low arousal index compared to adult OSA patients. We can observe general characteristics and particularity of pediatric OSA through this study.