• Journal of Magnetics
• /
• v.18 no.2
• /
• pp.81-85
• /
• 2013

We investigate the electronic and magnetic properties in Cu-doped InN with the N vacancy ($V_N$) from first principles calculations. There is the long-range ferromagnetic order between two Cu atoms, attributed to the hole-mediated double exchange through the strong p-d interaction between the Cu atom and neighboring N atom. The system of $V_N$ defect in Cu-doped InN has the lowest formation energy. Due to the hybridization between the Cu-3d and $V_N$ states, the spin-polarization on the Cu atoms in the InN lattice is reduced by $V_N$ defect. So, it shows a weak ferromagnetic behavior.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.02a
• /
• pp.334-334
• /
• 2013

In the past decade, the infrared detectors based on intersubband transition in quantum dots (QDs) have attracted much attention due to lower dark currents and increased lifetimes, which are in turn due a three-dimensional confinement and a reduction of scattering, respectively. In parallel, focal plane array development for infrared imaging has proceeded from the first to third generations (linear arrays, 2D arrays for staring systems, and large format with enhanced capabilities, respectively). For a step further towards the next generation of FPAs, it is envisioned that a two-dimensional metal hole array (2D-MHA) structures will improve the FPA structure by enhancing the coupling to photodetectors via local field engineering, and will enable wavelength filtering. In regard to the improved performance at certain wavelengths, it is worth pointing out the structural difference between previous 2D-MHA integrated front-illuminated single pixel devices and back-illuminated devices. Apart from the pixel linear dimension, it is a distinct difference that there is a metal cladding (composed of a number of metals for ohmic contact and the read-out integrated circuit hybridization) in the FPA between the heavily doped gallium arsenide used as the contact layer and the ROIC; on the contrary, the front-illuminated single pixel device consists of two heavily doped contact layers separated by the QD-absorber on a semi-infinite GaAs substrate. This paper is focused on analyzing the impact of a two dimensional metal hole array structure integrated to the back-illuminated quantum dots-in-a-well (DWELL) infrared photodetectors. The metal hole array consisting of subwavelength-circular holes penetrating gold layer (2DAu-CHA) provides the enhanced responsivity of DWELL infrared photodetector at certain wavelengths. The performance of 2D-Au-CHA is investigated by calculating the absorption of active layer in the DWELL structure using a finite integration technique. Simulation results show the enhanced electric fields (thereby increasing the absorption in the active layer) resulting from a surface plasmon, a guided mode, and Fabry-Perot resonances. Simulation method accomplished in this paper provides a generalized approach to optimize the design of any type of couplers integrated to infrared photodetectors.

• Animal Systematics, Evolution and Diversity
• /
• v.26 no.3
• /
• pp.337-339
• /
• 2010

A hole dwelling holothurian symbiotic crab was collected in the low tidal mark in Namhae Island. The crab was identified as Asthenognathus inaequipes Stimpson, 1858 and found to be new to Korean waters. The species was briefly illustrated and described.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2008.10a
• /
• pp.1477-1479
• /
• 2008

We report the first TTF compounds having columnar LC phase at room temperature. Based on the thermal, structural, and morphological observations, it was concluded that TTF derivative with long alkyl chains has highly ordered oblique columnar LC at room temperature. The new TTF derivatives have excellent oxidative stability which is desirable for a p-type (hole transport) materials.

• 제어로봇시스템학회:학술대회논문집
• /
• 2002.10a
• /
• pp.46.4-46
• /
• 2002

This study was motivated how it might be possible to validate structured sampling with orthogonal array for optimal design of a pin. The Taguchi method by orthogonal array, one of the structured sampling methods, has much advantage that is row cost and time saving for experiments. But this method has been applied in limited areas especially for mechanical problems. In this study, we experimented whether the structured sampling is useful for applying optimal design of mechanical elements. For the experiment, we first set up a mechanical problem which was related to determining optimal parameters associated a pin's crack occurred inside a hole. We, then, calculated combination of...

• Journal of The Korean Astronomical Society
• /
• v.34 no.4
• /
• pp.305-307
• /
• 2001

Radiation hydrodynamics in high. velocity or high optical-depth flow should be treated under rigorous relativistic formalism. Relativistic radiation hydrodynamic moment equations are summarized, and its application to the near-critical accretion onto neutron star is discussed. The relativistic effects can dominate the dynamics of the flow even when the gravity is weak and the velocity is small. First order equations fail to describe the intricate relativistic effects correctly.

• The Journal of the Acoustical Society of Korea
• /
• v.1 no.1
• /
• pp.92-96
• /
• 1982

In this paper, the interaction of electron and phonon in metals is expressed using Hamiltonian operator as follows. By excahnging phonon energy with in the vicinity of isotropical Fermi surface and using following electron and hole operators. We obtain the interaction of electron and phonon. And new Feynman Graphs are tried with the following conditions on. First, when state transfer state, phonon cannot be created. Second, when state transfer state, phonon cannot be destroyed. Third, when state transfer state, phonon can be created or destroyed. Fourth, when state transfer state, phonon can be created or destroyed.

• Journal of the Korean Geotechnical Society
• /
• v.31 no.1
• /
• pp.15-24
• /
• 2015

This paper presents the results of a reduced-scale physical model investigation into the effect of drilling fluid with different mix designs for bore hole collapse prevention. The bore hole collapse prevention mechanism for the bentonite based drilling fluid was first discussed together with the effect of conditioning with different additives on engineering characteristics of bentonite based drilling fluid. Reduced-scale model tests were then carried out considering field procedures for cases with a decomposed granitic soil with 20% fines and a sand with various drilling fluids with different mix designs. The results indicated that the addition of polymer to the bentonite based drilling fluid decreases the amount of drilling fluid injected, the drilling fluid infiltration thickness and increases the final depth of excavation. Also revealed is that the effect of polymer on the performance of drilling fluid is more pronounced in the decomposed granite soil with 20% fines than the sand. Practical implications of the findings from this study are discussed in great detail.

• Korean Institute of Interior Design Journal
• /
• v.16 no.1 s.60
• /
• pp.3-10
• /
• 2007

In the 7th century, Sachunwang-sa temple had two extra building-sites behind the Main hall. These two building-sites were found to be in peculiar form different from any another existing stone bases. The stone bases of northern put of these building-sites were decorated to molding as the protruding comers of eaves, which was pierced into a circular hole, and was carved into a form of Gomeck-ii(the stone bases lot supporting the wall). The northern building of sachunwang-sa temple was found to be used as the altar following munduru(文豆婁) method, through the observations of the archives of Samkukyusa(三國遺事) and the Abhiseka stura(skt. 灌頂經). The molding as the protruding cornets of eaves of stone bases was shaped as the roof of a building and the carving of Gomeck-ii gives a proof of the existence of the wall between columns in the altar. The hole of the stone bases protected the wooden cylinder of munduru from the exterior world. The author concludes, through this research, that the altar of Schunwang-sa temple was used lot the religious service during the war for worthship and protecting from the enemies. Also he concludes that these buildings must have been in wooden pagodas constructed upon a square plan, that is with both front and side width equal, haying a quite small scaled and low floored building with its first floor closed on all sides, being different item the usual form.

• The Bulletin of The Korean Astronomical Society
• /
• v.41 no.2
• /
• pp.34.1-34.1
• /
• 2016

The ultra hard X-ray band (14-195 keV) provides an important and unbiased way to understand black hole growth and relationship to the host galaxy. The Burst Alert Telescope (BAT) instrument on the Swift satellite has surveyed sky to unprecedented sensitivity, improving the number of known hard X-ray sources by more than a factor of 20 to 836 nearby AGN. The BAT AGN Spectroscopic Survey (BASS) is a study for the first large (N>600) and complete sample of ultra hard X-ray selected AGN with optical spectroscopy. In this talk, I present the observed relationship between black hole mass, bolometric luminosity, and Eddington ratio with optical emission line ratios. We show that [NII]/Ha ratio exhibits a significant correlation with Eddington ratio. We propose that the [NII]/Ha ratio is a useful indicator of Eddington ratio with 0.6 dex of scatter, and that it can be used to measure Eddington ratio and thus black hole mass from the measured bolometric luminosity, even for high redshift obscured AGN.