• Journal of the Korea Institute of Military Science and Technology
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• v.24 no.2
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• pp.211-218
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• 2021

This paper deals with the computational work to characterize the formation and pinching of a plasma in an X-pinch configuration. A resistive magnetohydrodynamic model of a single fluid and two temperature is adopted assuming a hollow conical structure in the (r,z) domain. The model includes the thermodynamic parameter of tungsten from the corrected Thomas-Fermi EOS(equation of state), determining the average ionization charge, pressure, and internal energy. The transport coefficients, resistivity and thermal conductivity, are obtained by the corrected Lee & More model and a simple radiation loss rate by recombination process is considered in the simulation. The simulation demonstrated the formation of a core-corona plasma and intense compression process near the central region which agrees with the experimental observation in the X-pinch device at Seoul National University. In addition, it confirmed the increase in radiation loss rate with the density and temperature of the core plasma.

• Journal of Digital Convergence
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• v.19 no.5
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• pp.461-468
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• 2021

The purpose of this study is to collect official records of the 2019 Men's and Women's Handball World Championships to identify important shooting variables that determine the team's record of winning or losing. After collecting 192 games of men's and women's national teams from 24 countries and verifying the difference in competition records according to the winning and losing groups, the decision tree method, one of the data mining techniques, is analyzed. According to the analysis, the 9m shooting success rate and Near shooting success rate were the most important factors for both men and women. Men win 83.3% if the 9m shooting success rate is 32.5% or higher and the Near shooting success rate is 67.5%, and women win 75% if the 9m shooting success rate is 75% or more and the Near shooting success rate is 51%. Also, the women's yellow cards are considered important variables that determine victory or defeat. In conclusion, both men and women were able to identify the factors of winning and losing decision shooting, but follow-up studies are needed considering the relativity of various record variables and performance in future handball.

• Environmental and Resource Economics Review
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• v.28 no.1
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• pp.61-93
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• 2019

This study is to apply Hedonic Price Method in analyzing residents' preferences for three types of urban green space (UGS, rivers, urban parks, and forests) near the apartment complexes in Seoul. Based on hedonic price function estimation results, residents in Seoul preferred for the urban amenity that was provided by the view and accessibility (in terms of both within 10 minutes and distance) of rivers and urban parks near the apartment complexes, but not forests. The annual benefits calculated using the shadow prices are about 550~600 thousand won for the urban park views and about 800 thousand won for the accessibility, which is 2-3 times higher than river views and accessibility. On the other hand, forest views and accessibility did not have significant effects on apartment prices, except the view of Bukhan mountain for the residents of Gangbuk area. Based on the empirical results, Seoul residents' preferences for urban parks would have important implications for the urban park sunset program that will be initiated from July 2020.

• Journal of the Korean Institute of Navigation
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• v.11 no.2
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• pp.33-52
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• 1987

The disasters of wet bound vessels have been more frequent than those of east bound ones on the sea routes of the North Pacific Ocean in winter season. M/V Hanjin-Inchon was also west bound in her missing voyage. The container vessel of 17, 676 gross tons, M/V Hanjin-Inchon owned by Hanjin Shipping Co.Ltd in Seoul Korea left seattle in west coast of U.S.A for Pusan , Korea on the 5th Feb., 1987 and sailed along the exact courses recommended by Ocean Routes until she reported her position and speed as 49-30N, 158-00E and 8 knots to her head office in Seoul by this ship's time 2200 hours on the 13th Feb., 1987. The above message turned out to be last message from her because she had been missing since then leaving no message but only two life boats of her name, three containers cases, large scale of oil slicks and the corpse of her 3rd mate drifting on the sea near the position reported by her last message.

• Agricultural and Biosystems Engineering
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• v.3 no.1
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• pp.1-9
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• 2002

Garlic is one of the major seasoning vegetables in Korea and consumed mostly in a form of peeled cloves. Conventional Korean standards for garlic grading consist of four classes according to the size of bulb and its shape. Sorting and grading of garlic are manually done but could be in the process of automated mechanization using machine vision system in the near future. The proportion of mass of cloves in a garlic bulb to the volume of the bulb (g/ml) was determined to find out the best way of representing both the quantity and quality of cloves in each bulb. Garlic bulb was assumed as an ellipsoid and its major and minor axis and its height were measured to calculate its volume. The mass proportions and density of a garlic bulb and cloves were measured for four domestic varieties of garlic to propose it as a standard for Korean garlic grading machine.

• Journal of The Korean Astronomical Society
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• v.14 no.1
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• pp.1-11
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• 1981

Photoelectric drift scans of nearby galaxies, M106, M31 and M33 have been made at diurnal rate with the 61cm Cassegrain Reflector at Sobacksan Observing Station. Luminosity profiles of M106 and M31 show the asymmetries between east and west sides of the galaxies and the near side of each galaxy exhibits a larger B-V color than the far side. B-V color distribution in the central part of MI06 shows somewhat unusual feature of a blue center with red surrounding regions, and this is an opposite trend to the ordinary color distribution of most of external galaxies. B-V color of M31 is nearly constant in the central part of the galaxy while U-B color decreases as the distance from the center increases.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.563-570
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• 2011

This study analyze the transfer patterns of passengers in Seoul based on transit smart card data that was observed in 2010. The smart card records maximum four times of transfer and reports that approximately 90% of trips were less than one transfer and the remains were more than 2 transfers. We focus on trips with more than 3 transfers to figure out the relationship between transit service and regional connectivities. The results show that the average travel time, distance, fare are 45 minutes, 18.3km, and 1,119(KW) respectively. We develope a map for investigating transfer patterns at a regional level(dong and gu). By doing this, three types of transfers are observed as: 1) trips of which origin and destination is either same or near, 2) trips with short distance, and 3) long distance trip with low transit connectivities.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.3
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• pp.49-54
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• 2001

It is common that the soil layer is a few meters below the earth's surface and the rock mass is below the soil layer in the view of geological characteristics in Korea. And the boundary between rock and soil is clearly divided. When dealing with the stability of rock masses, as in the case of rock slopes or dam foundations, the majority of the collapses is not within the soil layer, but within the soil-rock boundary. Therefore it is important to identify the shear strength characteristics between soil-rock boundary. And then in the method of reinforcement on landslide this chose a cut slope near Daemo elementary school in Seoul, surveyed shear strength between soil-rock contacts and considered a large scale collapse using a limit equilibrium method.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.503-525
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• 2012

Consumers are increasingly concerned about the origin of foods, so the geographical origin of foods has been a major topic of debate and extensive research. Various instrumental methods (e.g. high performance liquid chromatography (HPLC), gas chromatography (GC), capillary electrophoresis (CE), electronic nose, near-infrared spectroscopy (NIRS), nuclear magnetic resonance spectroscopy (NMR), DNA analysis, multi-isotope analysis) in conjunction with statistical analysis, were developed and applied in attempt to provide reliable answers to their geographical origin. This study reviews current developments in the application of various methods for a clear geographical origin of foods. The limitation of discrimination analysis for geographical origin was also discussed.

• Publications of The Korean Astronomical Society
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• v.1 no.1
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• pp.21-37
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• 1984

The origin of five small satellites (1980 S1, 1980 S3, 1980 S26, 1980 S27 and 1980 S28) and F-ring of Saturn which were recently discovered inside the orbit of Mimas, is proposed in terms of the resonant effects by external satellites in the Saturnian primordial extended ring. From the calculations of resonance locations and strengths, the following conclusion could be derived. Assuming that present two objects 1980 S1 and 1980 S3 were originally a single object 1980 S1+S3, 1980 S1+S3 had been formed due to Enceladus' 2/1 resonance and 1980 S26 due to Mimas' 3/2 resonance at first and then 1980 S28. 1980 S27 and F-ring were formed in the next due to 1980 S1+S3's 8/7, 9/8 and 10/9 resonances, respectively.