• Proceedings of the Plant Resources Society of Korea Conference
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• 2000.05a
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• pp.60-61
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• 2000

• Information Display
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• v.22 no.3
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• pp.34-42
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• 2021

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.1
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• pp.221-228
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• 2018

Big data is an important keyword in World's Fourth Industrial Revolution in public and private division including IoT(Internet of Things), AI(Artificial Intelligence) and Cloud system in the fields of science, technology, industry and society. Big data based on services are available in various fields such as transportation, weather, medical care, and marketing. In particular, in the field of sports, various types of bio-signals can be collected and managed by the appearance of a wearable device that can measure vital signs in training or rehabilitation for daily life rather than a hospital or a rehabilitation center. However, research on big data with vital signs from wearable devices for training and rehabilitation for baseball players have not yet been stimulated. Therefore, in this paper, we propose a system for baseball infield and outfield players, especially which can store and analyze the momentum measurement vital signals based on big data.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.4
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• pp.627-639
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• 1996

Charateristics of Ansan and Boryong coal fly ashes collected at different seasons were investigated for the recycling them as ceramic raw materials. The effect of pH treatment on the classification of Ansan coal fly ashes by elutriation was discussed. Charateristics of ansan and boryong coal fly ashes were not significantly changed with power plants and seasons. major crystalline phases were mullite and quartz. These results suggested that coal fly ashes cab be used as raw materials instead of clay minerals. However, particle size distribution was very broad from a few $\mu\textrm{m}$ to over $100\;\mu\textrm{m}$. Especially, ansan coal fly ashes have various morphologies. Therefore, coal fly ashes should be classified before using as raw materials. Because of higher dispersion by pH treatment, spherical cenospheres were mainly collected in the 4th step and particle size distribusion was also decreased by elutriation for the ansan coal fly ashes. The specific surface area of the sample collected in the 4th step was $1.24\;m^{2}/g$ which was smaller than that of not treated Ansan coal fly ashes.

• Journal of the Korean Geotechnical Society
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• v.18 no.5
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• pp.261-269
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• 2002

The objectives of this paper are to study the use of geotextile tribes for dewatering high water content sludges and sediments and to evaluate their feasibility and affecting fsctors. To accomplish these objectives, pressure filtration tests were conducted on woven geotextile (Geotex$\circledR$ 46T and 1212T) fir high water content materials with a modified experimental apparatus. Test results indicate that 1) the filter cake formed on the inside of the geotextile tube is the major contributor to the retention of fine particles, but also causes a decrease in permeability, 2) controlling the formation of the filter cake and thus achieving a balance between soil retention and permeability is vital to a successful project, and 3) geotextiles, sludge properties, and filtration pressures have some effects on the dewatering efficiency and dewatering rate.

• The Korean Journal of Applied Statistics
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• v.28 no.5
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• pp.1003-1011
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• 2015

We studied indices to explain runs lost for Korean professional baseball teams. Kim and Kim (2014) studied batting indices to explain run productivity of teams; subsequently, we studied fielding indices to explain runs lost. We considered several combined indices made by combining fielding indices closely connected with the runs lost of teams. Data analysis from all games in the regular seasons of 1982~2014 show that weighted WPH (defined as weighted average of WHIP and number of home runs allowed per game) best explain runs lost. Weighted WPH consisting of WHIP (with weight 81%) and number of home runs allowed per game (with weight 19%) was found optimal weighted WPH having correlation coefficient 0.95033 with average runs lost per game. Analysis by chronological periods gave results not much different.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.5 s.39
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• pp.35-43
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• 2004

Small-scale models have been frequently used for seismic performance tests because of limited testing facilities and economic reasons. However, there are not enough studies on similitude law for analogizing prototype structures accurately with small-scale models, although conventional similitude law based on geometry is not well consistent in the inelastic seismic behavior. When fabricating prototype and small-scale model of reinforced concrete structures by using the same material, added mass is demanded from a volumetric change and scale factor could be limited due to aggregate size. Therefore, it is desirable that different material is used for small-scale models. Thus, a modified similitude law could be derived depending on geometric scale factor, equivalent modulus ratio and ultimate strain ratio. In this study, compressive strength tests are conducted to analyze the equivalent modulus ratio of micro-concrete to normal-concrete. Then, equivalent modulus ratios are divided into multi-phase damage levels, which are basically dependent on ultimate strain level. Therefore, an algorithm adaptable to the pseudodynamic test, considering equivalent multi-phase similitude law based on seismic damage levels, is developed. Test specimens, consisted of prototype structures and 1/5 scaled models as a reinforced concrete column, were designed and fabricated based on the equivalent modulus ratios already defined. Finally quasistatic and pseudodynamic tests on the specimens are carried out using constant and variable modulus ratios, and correlation between prototype and small-scale model is investigated based on their test results. It is confirmed that the equivalent multi-phase similitude law proposed in this study could be suitable for seismic performance tests on small-scale models.

• Korean Journal of Cognitive Science
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• v.22 no.3
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• pp.255-270
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• 2011

The purpose of this study was to examine the effects of nonspecific and specific cue on decision making during situation awareness. Participants were 36 male college students who were randomly assigned to one of three groups: (1) nonspecific situation awareness, (2) specific situation awareness, and (3) a control group. Every participant was in the level 3-4.5 according to American National Tennis Level Program. Participants were asked to watch tennis single defence, single offence, double defence rally and when the screen stops, they were required to push the button(left, middle, or right) appropriate for the ball's direction to return as soon as possible. The experiment was designed to be analyzed for group(3)${\times}$condition(3)${\times}$area(7) using three-way ANOVA. The dependent variables were reaction time, accuracy rate, and amplitude and latency of P300. The result showed that the latency of the nonspecific situation awareness group and the specific situation awareness group was shorter and their amplitudes were higher than the control group. Fz, Cz, Pz were prominent among areas, and the single defence condition was more prominent than the single offence and the double defence condition. As a result of the study, it can be suggested that the information about situation awareness provided beforehand directly affects the brain's information processing. In addition, it shows that ERP can be a useful index for studying situation awareness.

• Journal of the Korean Geotechnical Society
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• v.28 no.2
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• pp.33-42
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• 2012

The purpose of this study is to determine the effect of soil grain size and its distribution on soil-water characteristic. To do this, soil-water characteristic tests were conducted on Saemangeum silt using the axis translation technique. For comparison, the test was also conducted on Jumunjin sand. Using the test results, the soil-water characteristic curves (SWCCs) of Saemangeum silt and Jumunjin sand were predicted by Van Genuchten model. By comparison and analysis between two SWCCs, the silt shows higher values of matric suction, water content, and air entry value than the sand. On the other hand, the sand has higher values of Van Genuchten model parameters of ${\alpha}$, $n$, $m$ than the silt. It indicates that the SWCC is significantly dependent on the structure of soils. In other words, if a soil has relatively high grain size and poor grain size distribution curve, the values of saturated volumetric water content, residual volumetric water content, and air entry value are small, and the variation of volumetric water content is high in accordance with the matric suction variation, and consequently it shows a narrow range of funicular region.

• Korean Journal of Cognitive Science
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• v.16 no.2
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• pp.141-154
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• 2005

The purpose of this study was to investigate the effects of implicit and explicit situation awareness instruction on decision making and event related brain potentials. Psychophysiological data obtained from 36 intermediated level tennis players whose National Tennis Rating Program(NTTP) belong 2 to 2.5 were compared. Participants were randomly assigned to one of three experimental groups: (1) implicit situation awareness, (2) explicit situation awareness, and (3) control group. A total of 90 clips were presented via a beam project screen, and participants pressed one of three jelly bean buttons to indicate the direction of ball hit. Dependent measures were the latencies and amplitudes of P300 on Pz, Cz, and Fz. The results of this study indicated that participants in the implicit situation awareness produced tenser P300, than participants in the explicit situation awareness group. The findings also indicated that single defense showed longer P300 latencies than single attack as well as double defense. The P300-amplitude of treatment groups were longer than control group. The Cz area showed shorer P300 latencies than Pz and Fz areas. In addition, single defense situation demonstrated longer P300 latencies than single attack and double defence situations. Based on this study, it is believed that implicit and explicit situation awareness instruction influence decision making in different ways.