• Journal of the Korean housing association
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• v.24 no.1
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• pp.61-68
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• 2013

This study tries to provide fundamental policy information for one-room housing by analyzing current living conditions of one-room housing near a university. For this purpose, this study conducts on-site survey as well as residents' survey. The main findings are follows. First, some one-room houses have been converted from single-family houses. Pilotis are often used as parking lots in newly built one-room houses. There are illegal equipments and illegal parkings around one-room village. Second, residents satisfy with proximity to workplace. However, they show strong dissatisfaction with physical environment such as noise, air flow, waste disposals. In particular, they feel very uncomfortable with gloomy lights and fear about potential crime. Third, residents like their independent lives, but complain about narrow living space and unprotected privacy. In addition, many of them feel lonely due to lack of public space in which residents can communicate.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.8
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• pp.208-215
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• 1999

Using the orthogonal arrays and the occupant analysis software based on the multi-body dynamics , two interactive design algorithms are proposed to improve the initial design of the occupant protection systems. Algorithm 1 sequentially moves the narrow design space within the upper and the lower design limit. Algorithm 2 sequentially reduces the relatively wide design space. Each design algorithm is composed of two levels . The first level is to improve the characteristics of the crash performance considering the noise factors. In order to obtain the robust design, the second level reduces the variations the noise factors. In order to obtain the robust design, the second level reduces the variations due to the tolerance of the design variable. To utilize the algorithm 1, HIC(Head Injury Criterion) , 3 msec criterion value of the chest acceleration and the femur load decreased by 27.4%, 10.4% and 55.8%, respectively. To utilizer the algorithm 2 , the results decreased by 38.0%, 10.5% and 3.0% , respectively.

• International Journal of Aeronautical and Space Sciences
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• v.14 no.3
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• pp.210-214
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• 2013

The sensitivity of transonic flow past a Whitcomb airfoil to deflections of an aileron is studied at free-stream Mach numbers from 0.81 to 0.86 and vanishing or negative angles of attack. Solutions of the Reynolds-averaged Navier-Stokes equations are obtained with a finite-volume solver using the $k-{\omega}$ SST turbulence model. The numerical study demonstrates the existence of narrow bands of the Mach number and aileron deflection angles that admit abrupt changes of the lift coefficient at small perturbations. In addition, computations reveal free-stream conditions in which the lift coefficient is independent of aileron deflections of up to 5 degrees. The anomalous behavior of the lift is explained by interplay of local supersonic regions on the airfoil. Both stationary and impulse changes of the aileron position are considered.

• Journal of The Korean Astronomical Society
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• v.39 no.4
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• pp.151-155
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• 2006

Long slit spectrometers are widely used in optical and infrared bands in astronomy. Absolute flux calibration for extended sources, however, is not straightforward, because a portion of the radiation energy from a flux calibration star is blocked by the narrow slit width. Assuming that the point spread function(PSF) of the star is circularly symmetric, we develop a robust method to extrapolate the detected stellar flux to the unobscured flux using the measured PSF along the slit-length direction. We apply this method to our long slit data and prove that the uncertainty of the absolute flux calibration is less than a few percents.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.68.2-68.2
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• 2011

We present the detailed image decomposition of Hubble Space Telescope archival images for 235 nearby (z < 0.35) unobscured type 1 AGNs. It allows us to perform robust measurements of host galaxy properties and AGN luminosity contribution. We examine how the host properties correlate with AGN properties. Broad line type 1 and radio-loud AGNs are hosted preferentially by early type galaxies. Narrow line type 1 AGNs show a low fraction of tidal interaction, that might suggest the secular evolution may play an important role for triggering AGN activity, while the fraction of merging hosts is rather higher in luminous AGNs. We compare the nucleus luminosity and bulge luminosity and find that either our sample might have a smaller zero point in the M(BH)-L(bulge) relation (i.e. less massive black hole at a given bulge luminosity) relation compared to the normal galaxies or Eddington ratio of our sample could be systematically overestimated.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.89-92
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• 2002

In this paper we present a barcode reader to decode two-dimensional symbology PDF-417 and propose a novel method to extract the bar-space patterns directly from the gray-level barcode image, which employs the location and the distance between extreme points of each row of the barcode image. This algorithm proves to be very robust from the high convolution distortion environments such as defocussing and warping, even under badly illuminating condition. If the scanned barcode image is a result of the convolution of a Gaussian-shaped point spread function with a bi-level image, popular image segmentation methods such as image thresholding can not distinguish between very narrow bar-space patterns with a couple of pixels wide. The proposed algorithm shows improved performance over current barcode readers.

• Journal of electromagnetic engineering and science
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• v.17 no.1
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• pp.34-38
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• 2017

In this paper, we propose an active tunable bandpass filter (BPF) for efficient spectrum sensing in the TV White Space (TVWS) band. By designing a narrow bandwidth, it is possible to improve the sensing probability. The basic circuit configuration involves switching the PIN diode compromising capacitor bank to change the capacitance of the LC resonant circuit. To cover the whole TVWS band effectively, we add a varactor diode, and the bandwidth is set to 25-MHz. We improve the insertion loss by using the active capacitance circuit. The tunable BPF in the TVWS band with a 20-MHz interval is designed to have 11 channels with a bandwidth of 25 MHz and a low insertion loss of 1.7-2.0 dB.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.43.3-43.3
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• 2016

Most globular clusters are now known to have two or more stellar populations with different chemical properties. In order to understand the origin and evolution of multiple stellar populations in these globular clusters, it is necessary to study not only the chemical property, but also the dynamical property. In our previous works (Lim et al. 2015; Han et al. 2015), we have shown that Ca narrow-band photometry can be combined with low-resolution spectroscopy to effectively study the chemical properties of globular clusters. In this talk, we will show our observations are also useful to study the radial distribution of stars in globular clusters with multiple stellar populations, and report our preliminary results.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.52.1-52.1
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• 2016

We introduce the characteristics and performance of the 0.25m telescope at Mangpo high school Unmanned Robotic Observatory (MURO) which was established in Yangpyeong-gun, Gyeongi-do, KOREA in 2015 January. MURO system included Astrohaven 2.1m non-rotation fiberglass clamshell dome, Paramount MEII mount, Takahashi CCA 0.25m wide field telescope, FLI PL 16803 4K CCD with 7-positions filter wheel system, all sky camera and point grey wide field camera, IR 4 chanel heat sensor camera for security, DAVIS realtime weather cast, and power controled by ARS system. All control softwares are from off-the-shelf products based on Windows 7 OS to be easily operated and maintained. We expect to perform variety of science programs ranging from supernovae follow-up observation to narrow band imaging survey as well as science class activities at Mangpo high school.

• International Journal of Aeronautical and Space Sciences
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• v.3 no.1
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• pp.30-38
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• 2002

In multi-dimensional systems, various solution schemes for radiative transfer are suggested but the applicabilities and accuracies of these schemes have not yet fully tested due to the lack of reference solutions especially for nongray gases. In this paper we present some precise radiative transfer solutions for a black walled 3-dimensional cylindrical system filled with nongray gases having uniform temperature and concentration. The ray-tracing method with the $T_N$ quadrature set and the SNB model are used to obtain the radiative transfer solutions by the nongray gases. The solutions presented in this paper are proved to be quite accurate and can be regarded as the reference solutions for the radiative transfer by nongray gases.