• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.4
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• pp.291-297
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• 2013

Automated weather stations were installed at 9 locations with, three different elevations, (i.e., 50m, 100m, and 300m a.s.l.) with different slope and aspect in a small watershed ($50km^2$ area). Air temperature at 1500 LST and solar radiation accumulated for 1100-1500 LST were collected from January to December 2012. Topography of the study area was defined by a $30{\times}30$ m digital elevation model (DEM) grid. Accumulated solar irradiance was calculated for each location with the spatially averaged slope and aspect of surrounding circles with 5, 10, 15, 20, 25, and 30 grid cell radii, respectively. The 1500 LST air temperature from clear sky conditions with zero cloud amount was regressed to the 1100-1500 LST solar irradiance at 9 locations. We found the highest coefficient of determination ($r^2$ = 0.544) at 25 grid cell radius and the temperature variation in this study was explained by Y = 0.8309X + 0.0438, where Y is 1500 LST temperature (in $^{\circ}C$) and X is 1100-1500 LST accumulated solar irradiance (in $MJ/m^2$).

• Journal of Korean Society for Atmospheric Environment
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• v.26 no.6
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• pp.591-605
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• 2010

Recirculation of airmass in coastal region occurs because of the change from land to sea breeze and was shown to produce a contrary result on air quality. This study examines the numerical simulation to analyze the effect of recirculation flow in Gwangyang Bay, Korea. For this purpose two case studies are performed by the WRF-FLEXPART-CMAQ modeling system, each for a different Meso-Synoptic Index. Additionally this research make a comparative study of large domain (Domain L) and small domain (Domain S). The horizontal wind fields are simulated from WRF. Changes in the land-sea breeze have an effect on the particle dispersion modeling. The numerical simulation of air quality is carried out to investigate the recirculation of ozone. Ozone is transported to eastward under strong synoptic condition (Case_strong) because of westerly synoptic flow and this pattern can confirm in all domain. However ozone swept off by the land breeze and then transported to northward along sea breeze under conditions of clear sky and weak winds (Case_weak). In this case re-advected ozone isn't simulate in Domain S. The study found that recirculation of airmass must be concerned when numerical simulation of air quality is performed in coastal region, especially on a sunny day.

• Physical Therapy Korea
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• v.12 no.1
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• pp.63-70
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• 2005

To compare the effects of forward walking and backward walking on surface electromyographic analysis of quadriceps muscles at treadmill grades of 0%, 5% and 10%, subjects were randomized to eleven athletics (5 females, 6 males), with a mean age of 17.8 years, and a SD of 4.66 years. The values of the surface electromyographic (SEMG) activity of the rectus femoris (RF), vastus lateralis (VL) and vastus medialis oblique (VMO) were measured during forward walking and backward walking on a treadmill at grades of 0, 5 and 10%. The subjects walked for approximately 10 seconds at 4.0 km/h. The data were analyzed by repeated measuring of the two-way ANOVA and analyzed by a paired t-test between forward walking and backward walking. The SEMG activity levels of the RF, VL and VMO were the highest when both the forward walking and backward walking increased incrementally for treadmill grades of 0% to 10%, but the VMO/VL ratio had no significant changes. The SEMG activity levels of the RF, VL and VMO were significantly different between directions. However, SEMG activity levels of the RF, VL, VMO and VMO/VL ratio did not show significant difference among the treadmill grades. No statistically significant interactions were detected between the direction of walking and treadmill grade. Backward walking on the treadmill at 4 km/h and grades of 0%, 5%, 10% elicited a greater SEMG activity on the quadriceps muscles than did forward walking under the same conditions. The results suggest that the quadriceps may be effectively activated by performance at treadmill grades of 10%. This investigation confirms that backward walking up an incline may place additional muscular demands on individuals.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.279-281
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• 2015

We adopt the PASTEL catalog combined with SIMBAD radial velocities as a testing standard to validate the stellar parameters (effective temperature $T_{eff}$, surface gravity log g, metallicity [Fe/H] and radial velocity $V_r$) from the first data release (DR1) of The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) survey. After applying data reduction and temperature constraints to the sample obtained by cross-identification, we compare the stellar parameters from DR1 and PASTEL. The results show that the DR1 results are reliable under certain conditions. We derive a dispersion of 110 K, 0.19 dex, 0.11 dex and $4.91kms^{-1}$ in specified effective temperature ranges, for $T_{eff}$, log g, [Fe/H] and $V_r$ respectively. Systematic errors are negligible except for those of $V_r$. In addition, for stars with PASTEL [Fe/H] < -1:5, the metallicities in DR1 are systematically higher than those in PASTEL.

• Aerospace Engineering and Technology
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• v.1 no.1
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• pp.173-176
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• 2002

This report summarizes the results of MODTRAN model that are used for the calculation of input radiance of the KOMPSAT-2 Multispectral Camera (MSC). We have calculated the input radiances for four months: January 15, April 15, July 15 and October 15. Annual averages are the arithmetic mean of results from four months. We used the mid-latitude winter and summer for the month of January and July, respectively, while US standard atmospheres are used for April and October. The orbital characteristics of KOMPSAT-2 and the seasonal variations of solar zenith angle over the Korean peninsula were incorporated as inputs to the model. The tropospheric aerosol extinction (visibility = 50 km) was assumed. The surface albedo used in the model calculation represents the global annual mean clear-sky albedo. MSC contract values are found to be considerably greater in the MSC spectral range than the total radiances calculated with the above general conditions. From these results, it can be inferred that the forthcoming MSC images would be somewhat dark. We certainly need a countermeasure for this issue.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.4
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• pp.545-552
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• 2013

This paper is a part of developing a computer code that can be used to generate IR images of a naval ship by considering the emitted and reflected infrared signals. The spectral radiance received by an IR sensor is consisted of the self-emitted component from the ship surface, the reflected component of the solar/sky irradiance at the ship surface, the emitted radiance from the ship surface and the exhaust plume gas, and the scattered radiance by the atmosphere. The plume gas radiance occupies a large part of the emitted radiance from a naval ship in operation. Therefore plume gas radiance must be taken into account when calculating the radiance from a naval ship for reliable IR images. In this paper, IR images of a naval ship with the exhaust gas effect in various environmental conditions are generated by using an exhaust gas prediction model called the JPL model. The contrast radiance (CR) values of the IR images are calculated to analyze the effect of the exhaust gas radiance quantitatively. The results obtained by quantitative analysis show that the IR signatures with the exhaust plume gas are 2.26 times larger than those neglecting the plume gas effect. The effect of the exhaust plume gas is shown to be more eminent in winter than in summer in the daytime.

• The Journal of Industrial Distribution & Business
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• v.12 no.11
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• pp.33-50
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• 2021

Purpose: In South Korea, two kinds of mandatory insurance, Fierce Liability Insurance and Outdoor Advertising Liability Insurance sells as of February 2021 according to relevant codes. This study analyzed third party liability and personal living liability insurance in terms of various risks not corporation side but personal side arising from normal living and life. Research design, data and methodology: Some cases of drone accident hit man and fierce dog accident were taken into analysis to verify blame ratio and insurance claim money. The former case is that on the way down the elevator, the dog, American pit bull terrier rushed in and bit the lower part of the knee against the visitor. The latter case is that while flying in the sky as usual, the drone suddenly crashed, fell, and hit the head of a young child while walking on the street. Further previous studies such as third party liabilities, liability insurance, mandatory insurance were deeply analyzed. Results: Based on some case studies and previous studies, the author suggested valuable comments in turn realization of insurer as provider, exhaustive creation and operation of mandatory insurance, realization of insured as demanded, and arrangements of laws and systems in special consideration of amendment of companion animal and exhaustive execution of mandatory insurance by the government. Conclusions: This study was about third party liability, personal living liability insurance and expansion of mandatory insurance caused by relevant laws by the government. In this study the author verified what issues were observed from two cases drone accident and fierce dog accident and then suggested some valuable comment as above both systemic plans and practical plans. First of all, the individual should get Comprehensive Property Insurance(CPI) that covers the risks of his/her own property arising from the everyday life. And then the individual should further buy Personal Living Liability Insurance(PLLI) in order to prepare 'accidents that may happen when, where, or how' and overcome the said accidents. Moreover, the individual should take a look every single insurance contract whether he/she has a special terms and conditions of Personal Living Liability Insurance(PLLI) or not.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.4_2
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• pp.561-570
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• 2023

This study was to evaluate the effect of different rinsing times and methods on the accuracy of temporary prostheses fabricated by 3D printing method. Sixty temporary prostheses were fabricated with LCD types of 3D printer(Halot-Sky, Creality, Shenzhen, China) and divided into six groups (n = 10) based on rinsing times and methods. All specimens were rinsed with 99% isopropanol alcohol for 5 and 10 min using three methods-hand washed, ultrasonic cleaning, and automated washing. All specimens were polymerized for 3 minutes under the same conditions. The marginal and internal gaps of specimens were examined using a replica technique. The light-body silicone thickness was measured at 6 reference points(Absolute marginal discrepancy, Marginal, Chamfer, Axial, Angle, and Occlusal gap). All measurements were performed by a stereomicroscope. Reference point images were taken at 100× magnification and then measured using an image analysis program. Statistical analysis was performed using Two-way ANOVA, One-way ANOVA, and the Kruskal-Wallis test (p = .05). The marginal and internal gaps were statistically different according to the rinsing methods and rinsing times(p < .001). In the rinsing time, the temporary prosthesis rinsed for 5 minutes group showed higher accuracy than 10 minutes group. In the rinsing method, the hand washing group showed higher accuracy than the automated washing group.

• Atmosphere
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• v.33 no.3
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• pp.307-317
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• 2023

This study investigates the physical mechanisms that contributed to the 2022 European record-breaking heatwave throughout May-August (MJJA). The European climate has experienced surface warming and drying in the recent decade (1979~2022) which influences the development of the 2022 European heatwave. Since its spatial pattern resembles the 2003 European heatwave which is a well-known case developed by the strong coupling of near-surface conditions to land surface processes, the 2022 heatwave is compared with the 2003 case. Understanding heatwave development is carried out by the European Centre for Medium-Range Weather Forecasts (ECMWF) Reanalysis version 5 (ERA5) and daily maximum surface temperature released by NCEP (National Centers for Environmental Prediction) CPC (Climate Prediction Center). The results suggest that the persistent high pressure along with clear sky tends to increase the downward shortwave radiation which leads to enhanced sensible heat flux with the land surface dryness. Terrestrial Coupling Index (TCI), a process-based multivariate metric, is employed to quantitatively measure segmented feedback processes, separately for the land, atmosphere, and two-legged couplings, which appears to the development of the 2022 heatwave, can be viewed as an expression of the recent trends, amplified by internal land-atmosphere interactions.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.39.1-39.1
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• 2021

The Local Volume Mapper(LVM) project in the fifth iteration of the Sloan Digital Sky Survey (SDSS-V) will produce large integral-field spectroscopic survey data to understand the physical conditions of the interstellar medium in the Milky Way, the Magellanic Clouds, and other local-volume galaxies. We are developing the LVM Instrument control software. The architecture design of the software follows a hierarchical structure in which the high-level software packages interact with the low-level and mid-level software and hardware components. We adopt the spiral software development model in which the software evolves by iteration of sequential processes, i.e., software requirement analysis, design, code generation, and testing. This spiral model ensures that even after being commissioned, the software can be revised according to new operational requirements. We designed the software by using the Unified Modeling Language, which can visualize functional interactions in structure diagrams. We plan to use the SDSS software framework CLU for the interaction between components, based on the RabbitMQ that implemented the Advanced Message Queuing Protocol (AMQP).