• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.3
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• pp.213-232
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• 2009

This document was prepared to review and summarize the analytical methods for airborne and bulk asbestos. Basic principles, shortcomings and advantages for asbestos analytical instruments using phase contrast microscopy(PCM), polarized light microscopy(PLM), X-ray diffractometer (XRD), transmission electron microscopy(TEM), scanning electron microscopy(SEM) were reviewed. Both PCM and PLM are principal instrument for airborne and bulk asbestos analysis, respectively. If needed, analytical electron microscopy is employed to confirm asbestos identification. PCM is used originally for workplace airborne asbestos fiber and its application has been expanded to measure airborne fiber. Shortcoming of PCM is that it cannot differentiate true asbestos from non asbestos fiber form and its low resolution limit ($0.2{\sim}0.25{\mu}m$). The measurement of airborne asbestos fiber can be performed by EPA's Asbestos Hazard Emergency Response Act (AHERA) method, World Health Organization (WHO) method, International Standard Organization (ISO) 10312 method, Japan's Environmental Asbestos Monitoring method, and Standard method of Indoor Air Quality of Korea. The measurement of airborne asbestos fiber in workplace can be performed by National Institute for Occupational Safety and Health (NIOSH) 7400 method, NIOSH 7402 method, Occupational Safety and Health Administration (OSHA) ID-160 method, UK's Health and Safety Executive(HSE) Methods for the determination of hazardous substances (MDHS) 39/4 method and Korea Occupational Safety and Health Agency (KOSHA) CODE-A-1-2004 method of Korea. To analyze the bulk asbestos, stereo microscope (SM) and PLM is required by EPA -600/R-93/116 method. Most bulk asbestos can be identified by SM and PLM but one limitation of PLM is that it can not see very thin fiber (i.e., < $0.25{\mu}m$). Bulk asbestos analytical methods, including EPA-600/M4-82-020, EPA-600/R-93/116, OSHA ID-191, Laboratory approval program of New York were reviewed. Also, analytical methods for asbestos in soil, dust, water were briefly discussed. Analytical electron microscope, a transmission electron microscope equipped with selected area electron diffraction (SAED) and energy dispersive X-ray analyser(EDXA), has been known to be better to identify asbestiform than scanning electron microscope(SEM). Though there is no standard SEM procedures, SEM is known to be more suitable to analyze long, thin fiber and more cost-effective. Field emission scanning electron microscope (FE-SEM) imaging protocol was developed to identify asbestos fiber. Although many asbestos analytical methods are available, there is no method that can be applied to all type of samples. In order to detect asbestos with confidence, all advantages and disadvantages of each instrument and method for given sample should be considered.

• Science of Emotion and Sensibility
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• v.17 no.2
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• pp.35-44
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• 2014

The purpose of this paper is to investigate the readability of Nearly White background color in display environment. To perform the experiment, warmup experiment was carried out to for cognitive of whiteness using a Tablet PC. The experiment environment was by a indoor window seat under a mixture of fluorescent light and sunlight. The result of previous test was that the most whiteness perception was a color white a medium wavelength and followed by the short wavelength. The main experiment was to find readability, color combination and visual strains using 4 nearly whites background colors (Reddish, Greenish, Blueish, Yellowish) and one white background color, also text color is limited on black. As a result, readability and color combination had the highest score against a Greenish white background. Visual strain is also the lowest against a Greenish background. On the contrary, readability and color combination preference has the lowest score against the Reddish background. Visual strain is also the highest against a Reddish background. We propose the background color, which improves readability and reduces visual strain in visual display terminals environment through the research results.

• Korean Journal of Medicinal Crop Science
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• v.9 no.2
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• pp.124-129
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• 2001

Crotalaria sessiflora is one of a few medicinal herbs among the legumes used as antitumor herb medicine but has lower seed germination and afterward seedling emergence. This study was carried out to elucidate the effects of cold stratification as presown treatment as well as $GA_3$, $KNO_3$ and acetone on its seed germination and seedling emergence. Cold stratification, $GA_3$, $KNO_3$ and acetone treatments were performed with different concentrations and period levels. Cold treatment was done under 14 hour red light illumination a day or darkness and the two others under darkness. On the basis of the best germination rate of each treatment, $GA_3$ and cold stratification treatments showed the highest germination rates at 0.1 mM but 12 hours and 2 week periods under darkness, respectively. $KNO_3$ and acetone treatments came out at 400 mM and 200 mM lasted for, respectively. The best germination rates from $KNO_3$ and acetone were comparatively higher than those from the former $GA_3$ and cold treatments. In evaluation of seedling emergence using the last two treatments, $KNO_3$ treated seeds were better performed than acetone treated seeds showed somewhat higher germination rate, implying that presown seed treatments must be evaluated by the combination with indoor and field tests.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.1
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• pp.129-135
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• 2015

The Ubiquitous City (U-City) spatial information technology aimed to provide services freely anytime and anywhere by converging high-tech information & communication technology in urban infrastructure has been available in diverse patterns. In particular, there have been studies on the development of 3D spatial information after selecting and matching key points with stereo images from the many Closed Circuit TV (CCTV) in the U-City. However, the data mostly used in extracting matching points haven't considered external environmental impacts such as illuminance. This study tested how much the matching points needed to construct 3D spatial information with the CCTV whose image quality is dependent upon changes in illuminance fluctuate under the same hardware performances. According to analysis on the number of matching points by illuminance, the number of matching points increased up to 3,000Lux in proportion to the illuminance when IRIS, shutter speed and ISO were fixed. In addition, a border between an object and background became more distinctive. When there was too much light, however, the page became brighter, and noise occurred. Furthermore, it was difficult to name key points because of the collapse of an inter-object border. It appears that if filmed with the study results, the number of matching points would increase.

• Journal of Aquaculture
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• v.19 no.3
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• pp.216-221
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• 2006

The Effect of different temperatures and photon irradiance on the growth of crust and the regeneration of tissue fragments of the commercially important red alga Grateloupia acuminat Okamura were examined in laboratory cultures. The tetraspore developed into basal crusts and produced upright thalli. Crust grew very fast at $25^{\circ}C$ and $80{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ after one week in indoor culture. However, they stopped growing after three weeks. Maximum growth was $275{\mu}m$ in diameter. They required four weeks to get upright thalli at $5^{\circ}C$, while only three weeks were required at $10^{\circ}C$. When different light intensities were compared at $15^{\circ}C$, cells of the crusts were well differentiated $80{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and consistently divided so that upright thalli were produced. In aeration culture, the upright thalli grew up to 6.5 cm in length within 4 months. Thus, it is possible to produce mass cultures of Grateloupia in the field. In addition, female and male gametophytes developed from the tetraspores and they were fertilized to produce tetrasporohyte thalli. By this procedure, the normal life cycle of the red alga G. acuminata was completed.

• Journal of the Korean Wood Science and Technology
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• v.43 no.1
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• pp.112-121
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• 2015

In this study, Copper Azole (CuAz), a domestically available wood preservative for pressure treatment, was employed to perform an experimental research on its infiltration and decay properties in Japanese Red Pine. Test specimens were pressure-injected with CuAz-2 preservative to measure its preservative effectiveness, and then its impact on weight and mass losses. Furthermore, wood specimens were treated with CuAz-2 preservatives of various concentration levels before they were decayed with brown-rot-fungi in order to observe decay properties on light microscope (LM) and field emission scanning electron microscope (FE-SEM). As a result, untreated specimen by Fomitopsis palustris showed the mass loss of more than 40%, and the value of preservative effectiveness of CuAz-2 by indoor decay was $1,73-3.32kg/m^3$. The concentration levels of CuAz-2 preservative were shown to cause significant variations in terms of decay progresses in the cross section, radial section, and tangential section. By contrast, untreated specimens had underwent serious decays in early wood, late wood, longitudinal resin canals, and ray, which led to vertical destruction of wood texture. As for the radial section, ray tracheid, ray parenchyma cell, and window like pits were decayed and destroyed. In the case of tangential section, uniseriate rays and vertical resin canals were seriously decayed. In conclusion, this study indicates that the adequacy of the current CuAz injection amount should be reviewed in the domestic environment because there are significantly different decays at different decay conditions.

• Particle and aerosol research
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• v.13 no.4
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• pp.151-158
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• 2017

Electrostatic precipitator is widely used to remove particulate matters in indoor air and industrial flue gas due to low pressure drop and high collection efficiency. However, it has a low collection efficiency for the submicrometer sized particles. Electrospraying is a potential method to increase the particle charging efficiency, which results in increased collection efficiency. Although particle charging efficiency is highly dependent upon droplet size, the effective measuring method of the droplets is still uncertain. Tap water was electrosprayed in this study, and the images of electrosprayed droplets were taken with a high speed camera coupled with several visualization methods in order to measure the droplets size. The droplet size distribution was determined by an image processing with an image-J program. As a result, a droplet measured by a laser visualization, had a half size of that by a Xenon light visualization. In addition, the experimentally measured droplet sizes were a good agreement with the predicted values suggested by $Fern{\acute{a}}ndez$ de la Mora and Loscertales(1994).

• Korean Journal of Remote Sensing
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• v.35 no.5_2
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• pp.841-850
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• 2019

The purpose of this study is to strengthen the capability of rapid mapping for disaster through improving the positioning accuracy of mapping and fusion of multi-sensing point cloud data derived from Unmanned Aerial Vehicles (UAVs) and disaster investigation vehicle. The positioning accuracy was evaluated for two procedures of drone mapping with Agisoft PhotoScan: 1) general geo-referencing by self-calibration, 2) proposed geo-referencing with optimized camera model by using fixed accurate Interior Orientation Parameters (IOPs) derived from indoor camera calibration test and bundle adjustment. The analysis result of positioning accuracy showed that positioning RMS error was improved 2~3 m to 0.11~0.28 m in horizontal and 2.85 m to 0.45 m in vertical accuracy, respectively. In addition, proposed data fusion approach of multi-sensing point cloud with the constraints of the height showed that the point matching error was greatly reduced under about 0.07 m. Accordingly, our proposed data fusion approach will enable us to generate effectively and timelinessly ortho-imagery and high-resolution three dimensional geographic data for national disaster management in the future.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.59-59
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• 2019

본 연구는 몇 가지 광량 조건하에서 자생 동백나무속 상록활엽 목본 2종의 생육 및 엽록소 형광 반응을 조사함으로써 실내 도입가능 여부를 판단하고자 수행되었다. 연구재료는 2년생 차나무[Camellia sinensis (L.) Kuntze] 삽목묘와 3년생 동백나무(C. japonica L.) 실생묘를 사용하였다. 실내 광환경의 사전조사를 토대로 광량을 10, 50, 100 및 200 PPFD (${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$)로 달리하였으며, 실험기간 동안 광 주기(12/12 h), 온도($25{\pm}1^{\circ}C$) 및 습도($55{\pm}3%$)를 통일하였다. 총 8주간 재배하였으며, 유리온실에서 동일기간 동안 재배중인 식물을 대조구로 비교하였다. 연구의 결과, 차나무는 50 PPFD 이상의 조건에서 초장, 줄기직경, 엽수 및 엽장 등의 생육이 대조구와 유사한 수준이었다. 그러나 10 PPFD에서는 모든 식물체의 잎이 말리거나 떨어지는 등의 관상가치가 저하되었으며, 엽록소 함량은 유의적으로 광량에 반비례하는 경향을 보였다. 엽록소 형광 반응은 100, 200 PPFD의 광량에서 모든 조사 항목이 대조구와 유사하였다. 동백나무는 50 PPFD에서 25%의 고사율이 나타냈다. 100 또는 200 PPFD에서 전반적인 생육이 대조구와 유사하거나 우수하였으며, 엽폭과 SPAD는 광량에 관계없이 유의적인 차이가 없었다. 또한 100, 200 PPFD의 엽록소 형광 반응은 모든 조사 항목에서 대조구와 비슷하거나 우수한 결과를 보였다.

• Korean Journal of Optics and Photonics
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• v.26 no.2
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• pp.73-82
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• 2015

This work demonstrates the indoor SI-traceable calibration of a transmissometer with a 75-m baseline for the measurement of visibility in MOR (Meteorological Optical Range). The calibration is performed using a set of neutral density (ND) filters (OD 0.1-2.5) and a set of high-transmission quartz glass plates (a bare quartz glass plate and antireflective-coated quartz glass plates), the collection consisting of 20 artifacts in total. The luminous transmittance values of the reference artifacts had been calibrated traceable to the KRISS spectral transmittance scale, which ranges from 0.2 % to 99.5 %. The transmissometer to be calibrated typically consists of a loosely collimated light source based on a white LED (CCT ~5000 K) and a luminous intensity detector with a CIE 1924 V(${\lambda}$) spectral response. As a result of calibration, we obtained the MOR error and its uncertainty for the transmissometer in 20 m - 40 km of MOR. Based on the results, we investigated the applicability of the calibration method and the conformity of the transmissometer to the ICAO's (International Civil Aviation Organization) accuracy requirement for meteorological visibility measurement. We expect that this work will establish the standard procedure for the SI-traceable calibration of a transmissometer.