• Journal of Information Display
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• v.10 no.2
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• pp.62-67
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• 2009

To understand panel driving more accurately, the optical properties and their distributions in the LCD panel itself, excluding the backlight, were investigated by measuring the transmittance of a one-dot pixel as a function of time. First, the behavior of time-dependent transmittance was analyzed, and it was found that the off-state TFT was not in a steady state but in a transient state during the holding period. Second, the time average, max, min, and range values of the transmittance curves were examined by varying the common voltage level and gray scale. Third, the analysis of such properties was expanded to cover those of the entire panel in all the gray scales. Lastly, the relationship between their properties and distributions was also investigated along with the contour plots.

• Journal of Korea Society of Digital Industry and Information Management
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• v.12 no.4
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• pp.107-114
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• 2016

Recently, 3D related technology has become a hot topic for IT. 3D technologies such as 3DTV, Kinect and 3D printers are becoming more and more popular. According to the flow of the times, the goal of this study is that the general public is exposed to 3D technology easily. we have developed a web-based application program that enables 3D modeling of facial front and side photographs using a mobile phone. In order to realize 3D modeling, two photographs (front and side) are photographed with a mobile camera, and ASM (Active Shape Model) and skin binarization technique are used to extract facial height such as nose from facial and side photographs. Three-dimensional coordinates are generated using the face extracted from the front photograph and the face height obtained from the side photograph. Using the 3-D coordinates generated for the standard face model modeled with the standard face as a control point, the face becomes the face of the subject when the RBF (Radial Basis Function) interpolation method is used. Also, in order to cover the face with the modified face model, the control point found in the front photograph is mapped to the texture map coordinate to generate the texture image. Finally, the deformed face model is covered with a texture image, and the 3D modeled image is displayed to the user.

• Journal of Astronomy and Space Sciences
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• v.29 no.4
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• pp.407-411
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• 2012

Space-borne remote sensing is an effective and inexpensive way to identify crop fields and detect the crop condition. We examined the multi-temporal spectral characteristics of rice fields in South Korea to detect their phenological development and condition. These rice fields are compact, small-scale parcels of land. For the analysis, moderate resolution imaging spectroradiometer (MODIS) and RapidEye images acquired in 2011 were used. The annual spectral tendencies of different crop types could be detected using MODIS data because of its high temporal resolution, despite its relatively low spatial resolution. A comparison between MODIS and RapidEye showed that the spectral characteristics changed with the spatial resolution. The vegetation index (VI) derived from MODIS revealed more moderate values among different land-cover types than the index derived from RapidEye. Additionally, an analysis of various VIs using RapidEye satellite data showed that the VI adopting the red edge band reflected crop conditions better than the traditionally used normalized difference VI.

• Applied Science and Convergence Technology
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• v.24 no.6
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• pp.257-261
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• 2015

We report on GaAs/AlGaAs quantum well infrared photodetectors (QWIPs) that can cover the spectral range of $3.6-25{\mu}m$. One advantage of the GaAs QWIPs is the wavelength tenability as a function of their structural parameters. We have performed a systematic calculation on the detection wavelength of a typical $GaAs/Al_xGa_{1-x}As$ multi-quantum-well photodetector, with the aluminum mole fraction (x) of $Al_xGa_{1-x}As$ barrier in the range of 0.15-0.43 and the quantum-well width range from 30 to 60 $60{\AA}$. Design and fabrication of a QWIP based on $GaAs/Al_{0.23}Ga_{0.77}As$ structure with $37{\AA}$-thick well width has been carried out. The calculated operation wavelength of the QWIP is in a good agreement with the experimental data taken by photo response and activation energy calculation from thermal quenching of integrated photoluminescence.

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.08a
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• pp.100-113
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• 2005

Leaf color and plant vigor are key indicators of crop health. These visual plant attributes are frequently used by greenhouse managers, producers, and consultants to make water, nutrient, and disease management decisions. Remote sensing techniques can quickly quantify soil and plant attributes, but it requires humans to translate such data into meaningful information. Over time, scientists have used reflectance data from individual wavebands to develop a series of indices that attempt to quantify things like soil organic matter content, leaf chlorophyll concentration, leaf area index, vegetative cover, amount of living biomass, and grain yield. The recent introduction of active sensors that function independent of natural light has greatly expanded the capabilities of scientists and managers to obtain useful information. Characteristics and limitations of active sensors need to be understood to optimize their use for making improved management decisions. Pot experiments involving sand culture were conducted in 2003 and 2004 in a green house to evaluate corn and red pepper biomass. The rNDVI, gNDVI and aNDVI by ground-based remote sensors were used for evaluation of corn and red pepper biomass. The result obtained from the case study was shown that ground remote sensing as a non-destructive real-time assessment of plant nitrogen status was thought to be a useful tool for in season crop nitrogen management providing both spatial and temporal information.

• Archives of Reconstructive Microsurgery
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• v.25 no.2
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• pp.69-71
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• 2016

Reconstruction of the lower extremities is difficult due to a lack of skin laxity and muscular tissues. Here, we present a case of lower extremity reconstruction via the anterior tibial artery perforator based segmental muscle island flap. Our patient was a 75-year-old male with a chronic ulcerative wound on the right lower leg from an old car accident. A $5.0{\times}0.5cm$ size ulcerative wound with tibial bone exposure was noted. We planned to reconstruct the lower extremity defect with a free flap, but the vessel status was severely compromised intraoperatively. Thus, we found the anterior tibial artery perforator using Doppler ultrasound, elevated the tibialis anterior muscle segment flap, and transposed it to cover the defect successfully. The flap presented with a nice contour and the skin graft covering the flap survived completely. There were no complications of the surgical site at three months follow-up and no gait morbidity. This is a meaningful case applying the concept of segmental muscle flap based on a perforator that had advantages including proper bulkiness, vascularization, and preservation of function, which were well applied, leading to great success.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.3
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• pp.69-75
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• 2014

The priority of repair areas are chosen with the probability distribution of 0.3mm wide crack and carbonation induced corrosion. Data is analyzed and evaluated based on the 28 section of Precise Inspection for Safety and Diagnosis (PISD) in seoul. As the crack is distributed in log-normal, the carbonation and cover are in normal distribution. To have rational in repair sections among 503 sheets of underground structure, it is adopted the reliability index as well as the environment factors: strength, sonic speed, $CO_2$ concentration, corrosion, and content of chloride.

• Journal of the Korean Society for Railway
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• v.12 no.5
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• pp.656-662
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• 2009

In general, the analysis of travelers' mode choice behavior is accomplished by developing the utility functions which reflect individual's preference of mode choice according to their demographic and travel characteristics. In this paper, we propose a methodology that takes the spatial effects of individuals' departure locations into account in the mode choice model. The statistical models considered here are spatial logistic regression model and conditional autoregressive model taking a spatial association parameter into account. We employed the Bayesian approach in order to obtain more reliable parameter estimates. The proposed methodology allows us to estimate mode shares by departure places even though the survey does not cover all areas.

• Atmosphere
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• v.14 no.2
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• pp.11-22
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• 2004

A technique on atmospheric correction algorithm to the multi-band reflectance of Landsat TM imagery has been developed using an atmospheric radiation transfer model for eliminating the atmospheric and surface diffusion effects. Despite the fact that the technique of satellite image processing has been continually developed, there is still a difference between the radiance value registered by satellite borne detector and the true value registered at the ground surface. Such difference is caused by atmospheric attenuations of radiance energy transfer process which is mostly associated with the presence of aerosol particles in atmospheric suspension and surface irradiance characteristics. The atmospheric reflectance depend on atmospheric optical depth and aerosol concentration, and closely related to geographical and environmental surface characteristics. Therefore, when the effects of surface diffuse and aerosol reflectance are eliminated from the satellite image, it is actually corrected from atmospheric optical conditions. The objective of this study is to develop an algorithm for making atmospheric correction in satellite image. The study is processed with the correction function which is developed for eliminating the effects of atmospheric path scattering and surface adjacent pixel spectral reflectance within an atmospheric radiation model. The diffused radiance of adjacent pixel in the image obtained from accounting the average reflectance in the $7{\times}7$ neighbourhood pixels and using the land cover classification. The atmospheric correction functions are provided by a radiation transfer model of LOWTRAN 7 based on the actual atmospheric soundings over the Korean atmospheric complexity. The model produce the upward radiances of satellite spectral image for a given surface reflectance and aerosol optical thickness.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1993.05a
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• pp.77-77
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• 1993

Laryngeal web is formed from various causes, and it is a scar tissue covered with epithelium on both sides. The purpose of the laryngeal web surgery is to cover the vocal cords with healthy epithelium and to achieve the normal or near normal function of respiration and phonation. Until now, a lot of surgical procedures were introduced, but have some merits and disadvantages. Recently authors tried this new surgical technique on 6 patients using the suspension laryngomicroscope under the intubation general anesthesia, which was to suture the upper and lower edges of the severed web. This new approach has several advantages; 1) familiar instruments and visual field 2) no unnecessary surgical trauma beyond the operation field 3) one stage operation 4) shorter operation time 5) no serious complications 6) short hospitalization, etc.