• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.146-147
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• 2000

The electromagnetic wave scattering from active objects has only recently attracted attention.$^{(1).(3)}$ Theoretical studies have considered normal-incidence plane-wave interactions with active dielectric cylinders with the prediction of large enhancements in the scattered field for bound mode structures. According to the theory of the electromagnetic wave scattering from a dielectric cylinder, the eigenvector solutions are discrete and have both guided (non-radiative) and leaky (radiative) mode solutions. By using an anti-guiding (leaky) structure instead of a guided structure and scattering at oblique incident angles near critical angle, the scattering resonances predicted by theoretical studies were obtained for the first time. A fine-grained scan of the plane-wave incident angle a reveals the existence of discrete scattering resonances. The diameter and real part of the index of refraction determine the resonant conditions and the imaginary part of the refractive index has a threshold value to make mode up for its radiation loss. The cross coupling between transverse electric (TE) and transverse magnetic (TM) modes is clearly detected for both active and passive scattering as theoretically expected. (omitted)

• Proceedings of the Optical Society of Korea Conference
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• 2009.10a
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• pp.331-332
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• 2009

We present an analysis on the quality factors of the Fourier hologram generated from multiple orthographic view images of three-dimensional object. In the analysis, we analyze both the maximum size of the reconstructed object and its spatial resolution. For the maximum size of the reconstruction, we found that the main factor is the orthographic projection angle interval. Too large projection angle interval causes overlapping in the reconstruction space domain. For the spatial resolution, there are three factors, i.e. the capturing lens array pitch which determines the spatial sampling rate of the original three-dimensional objects, the maximum orthographic projection angle, and the spatial frequency bandwidth of the object. The dominant factor is determined by the relationship between those three factors.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.87.1-87.1
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• 2010

Main-belt comets (hereafter MBCs) are one of the hottest topics in the solar system astronomy. They are objects orbiting in the main asteroid belt which show cometary activity. Unlike most comets, which spend most of their orbit beyond 5AU from the Sun, MBCs follow near-circular orbits within the asteroid belt that are indistinguishable from the orbits of major population of the asteroids. P/2010 A2, the fifth MBC, was discovered by on January 6, 2010 by Lincoln Near-Earth Asteroid Research. It passed its perihelion at 2.01AU on December 3, 2009, about a month before it was discovered. With an aphelion of only 2.6 AU, P/2010 A2 spends all of its time inside of the frostline ~2.7 AU. We made observations of P/2010 A2 with Nishi-Harima Astronomical Observatory 2-m telescope only a week after the discovery. From the observed images, we found that the dust cloud was composed of large particles (>1mm) impulsively ejected between March and June, 2009. No coma was detected by our observations, suggesting that this object was no longer active. Consequently, we conjecture that these dust particles could be released by the impact collision among asteroids.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.53.3-53.3
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• 2017

While quasars are sparse in number density, they reside at relatively high-redshift as compared to galaxies. Hence, they are likely to be less non-linearly evolved than the galaxy population, and thus have a distribution that more closely mirrors the primordial density field. Therefore, they offer an intriguing opportunity to search for primordial non-Gaussianity (PNG). To this end, the 3-point correlation function (3PCF) is an excellent statistical tool to detect departures from Gaussianity, vanishing for a Gaussian field. In this work, we will make the first-ever measurement of the large-scale quasar 3PCF from the SDSS-IV DR14 quasar sample (spanning the largest volume to-date) to place constraints on PNG through the usual f_NL-type parametrization. This work will use the order N^2-time 3PCF algorithm of Slepian & Eisenstein (2015), with N the number of objects.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.66.3-67
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• 2018

We present distinct chemical and kinematic properties associated with the inner and outer halos of the Milky Way, as identified by metal-poor stars from the Sloan Digital Sky Survey. In particular, using carbon-enhance metal-poor (CEMP) giants, we first map out the fractions of CEMP-no stars (without strongly enhanced neutron-capture elements) and CEMP-s stars (with a large enhancement of s-process elements) in the inner- and outer-halo populations, separated by their spatial distribution of carbonicity ([C/Fe]). The CEMP-no and CEMP-s objects are classified by their different levels of absolute carbon abundances, A(C). We investigate characteristics of rotational velocity and orbital eccentricity for these sub-classes within the halo populations. Distinct kinematic features and fractions between CEMP-no and CEMP-s stars identified in each halo region will provide important clues on the origin of the dichotomy of the Galactic halo.

• Journal of the Korean housing association
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• v.14 no.5
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• pp.117-128
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• 2003

The purpose of this study is to investigate the effect of functional ability on relocation among the elderly. Longitudinal data from the Asset and Health Dynamics among the Oldest Old (1993, 1995) were analyzed for 6,225 respondents aged 70 or older. Among functional ability measures, difficulties in advanced activities of daily living (i. e., making telephone calls, taking medications, and managing money), lower body activities (i. e., walking several blocks, climbing one flight of stairs, pulling or pushing large objects, and carrying over 10 pounds), and household activities of daily living (i. e., preparing hot meals and shopping for groceries) were the predictors of increased residential move. Difficulties in basic activities of daily living (i. e., bathing, dressing, getting in and out, and using the toilet) were strongly related to increased entrance into an institutional care facility. Efforts to enhance the independent living of the elderly in the community setting should target the compensation of these functional difficulties.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2004.11a
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• pp.343-348
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• 2004

Since its foundation of Won-Buddhism in 1916 there established around 500 Temple-Halls in both domestic and overseas areas, and it is a native religion that currently on its development of edification activities. As for Won-Buddhism which being under rapid development likely as such going, together with its expansion of the religious influence, there required more broader spaced grand sanctum at where the large-scaled religious events are able to perform. According to this, Balcony-styled plane form is on increasing trend from the internal plane form of Won Buddhism Sanctum. On such viewpoint, this study hereby intends to grasp the character of room acoustics through on-the-spot survey about the objects of 3 Won Buddhism Sanctums which equipped with mutually different characters of the balconies already built, and willing to furnish the fundamental material which enables to improve acoustic capability when design Won Buddhism Sanctum equipped with balcony in the future.

• Journal of the Korea Computer Industry Society
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• v.2 no.6
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• pp.845-852
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• 2001

Electronic commerce and application service is to universal on the internet, and a large quantity information transmitted on the network, It's needs procedure to access only permit objects for the integrity of information. In order to provide regional services is authentication for control resource and client identification. In particular, public key system is to implement in distributed environment, it is able to insurance users convenience and integrity at the same time. In this paper designed mechanism of cross certification between realms in PKI based on X.509 associated with DNS (Domain Name System) that is presented.

• Journal of information and communication convergence engineering
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• v.8 no.6
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• pp.697-701
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• 2010

The numbers of digital video cameras are fast increased. Accordingly, digital video data management is becoming more important. Efficient storing method and fast browsing method still remains to be one of significant issue. In this paper, an optimized data storing process without losing information and an organized appearance features indexing method are proposed. Also, the data removing policy could be used to reduce large amount of space and it facilitates fast sequential search. The appearance features index constructs key information of moving objects to answer queries about what people are doing, particularly when, where and who they move. The evaluation results showed better performance in the transfer time and the saving in storage space.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.3
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• pp.358-367
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• 2012

A study on tidal turbine using CFD simulation has been an economical and reliable method. However, large flow fields with multi-turbine arrays require high computer performance. Actuator disc theory therefore is widely applied. Actuator disc is the concept that imitates actual turbine by means of an energy absorption disc which has the same dimension and characteristics. Turbines installed in array may have disturbance effects on one another. Thus, the subject of this study is to analyze the far wake of these tidal turbines and compare to single turbine case. The main objects are to analyze two turbines positioned longitudinally at different spaces.