• The Journal of Korean Association of Computer Education
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• v.12 no.1
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• pp.45-55
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• 2009

The purpose of this study was to examine the possibility of development of flow level and problem-solving ability by Using robots in the programming classes. For this purpose, a course has been developed which consists of (1) strategies to motivate students and to improve flow level (2) Creative Problem Solving (CPS) teaching model to improve their problem solving abilities. We experimented the course with 30 second-grade middle school students and we could observe that the robot programming learning considered gender differences helps improving their problem solving abilities and flow level. Specially, the group of the female student was greater improvement than the group of the male student on flow level.

• Journal of the Korean Society of Clothing and Textiles
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• v.45 no.5
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• pp.907-921
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• 2021

This study aims to predict causal relationships between experience economy, perceived flow, and continuous use intention in the mixed reality (MR) environment. A virtual fitting mirror with two modes (i.e., avatar and self-image) was selected for this study. A total of 200 samples was obtained in two sample frames: virtual fitting users in avatar mode (group 1, n = 119) and self-image mode (group 2, n = 81). The results showed that the experience economy consists of entertainment, education, esthetic, and escapism. The entertainment and esthetic experiences had positive effects on perceived flow, leading to continuous use intentions. For avatar mode, the entertainment and esthetic experiences had positive effects on continuous use intentions through the mediating effect of flow; and the education experience had a positive effect on the continuous intentions to use the MR technology. For self-image mode, the flow mediated the effect of entertainment on continuous use intentions, whereas education and escapism directly affected the intention to use the MR technology. The paper also discusses the theoretical and managerial implications of using MR technologies in fashion retailing.

• Nuclear Engineering and Technology
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• v.55 no.5
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• pp.1742-1756
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• 2023

The hydrogen behavior in a nuclear containment vessel is a significant issue when discussing the potential of hydrogen combustion during a severe accident. After the Fukushima-Daiichi accident in Japan, we have investigated in-depth the hydrogen transport mechanisms by utilizing experimental and numerical approaches. Computational fluid dynamics is a powerful tool for better understanding the transport behavior of gas mixtures, including hydrogen. This paper describes a Large-eddy simulation of gas mixing driven by a high-buoyancy flow. We focused on the interaction behavior of heat and mass transfers driven by the horizontal high-buoyant flow during density stratification. For validation, the experimental data of the Containment InteGral effects Measurement Apparatus (CIGMA) facility were used. With a high-power heater for the gas-injection line in the CIGMA facility, a high-temperature flow of approximately 390 ℃ was injected into the test vessel. By using the CIGMA facility, we can extend the experimental data to the high-temperature region. The phenomenological discussion in this paper helps understand the heat and mass transfer induced by the high-buoyancy flow in the containment vessel during a severe accident.

• Speech Sciences
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• v.15 no.2
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• pp.177-189
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• 2008

This study was to investigate diadochokinetic (DDK) rate, regularity and mean flow rate of articulation valves in dysarthria. DDK rate, mean airflow rate (MFR) and regularity of DDK syllable repetitions of vocal function /ihi/, tongue function /ta/, velopharyngeal function /bm/, and labial function /pa/ in 24 normal and dysarthric speakers were measured. Aerophone Ⅱ and Motor Speech Profile were used for data recording and analysis. The results of the findings were as follows: First, there were significant differences between the dysarthria and the normal group in DDK rate. DDK rates in ataxic dysarthria were the lowest and spastic, flaccid, and hypokinetic dysarthria followed in sequence. Second, there was a significant difference between the dysarthria and the normal group in DDK regularity. Third, there was a significant difference between dysarthria groups and normal group in DDK MFR. Finally, there was a significant difference between the 4 groups of dysarthria and the normal group in DDK air flow tracking. The results of this study can be guidelines for normal DDK rate, regularity and flow rate in dysarthria groups. In addition, their differential diagnoses and descriptions are important to make a decision on medical and behavioral management of the individuals with disorders according to DDK characteristics.

• The Journal of Korean Medicine
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• v.17 no.2 s.32
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• pp.161-167
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• 1996

For the purpose of developing a new drug against cerebral infarction, we chose Ijintang which is frequently applied in the field of Jung Pung of traditional medicine. From this formula, water extract and methanol extract were prepared respectively. Animals were divided into three groups; control group, water extract medicated group, methanol extract treated group. water extract was given 195mg／kg orally and methanol extract, 165mg／kg for 2 weeks in case of cerebral edema and 1 month in regional cerebral blood flow. On the regional cerebral blood flow, the drug medicated groups showed no significant changes as compared gith control group. There was no significant difference on the cerebral edema among the groups. According to the results above, it is suggested that oral medication of water extract and methanol extract from Ijintang have no effect on the change of rCBF and edema after acutely induced cerebral infarction. However, it is thought that modification of administration method and development of new animal model for traditional medicine are needed.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.10a
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• pp.481-486
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• 1997

The interfacial shear stress is experimentally investigated for co-current air-water stratified flow in inclined rectangular channels having a length of 1854mm, width of 120mm and height of 40mm at almost atmospheric pressure. Experiments are carried out in several inclinations from $0^{\circ}\;up\;to\;10^{\circ}$. The local film thickness and the wave height are measured at three locations, i.e., L/H = 8,23, and 40. According to the inclination angle, the experimental data are categorized into two groups; nearly horizontal data group ($0^{\circ}\;{\leq}\;{\theta}\;{\leq}\;0.7^{\circ}$), and inclined channel data group ($0.7^{\circ}\;{\leq}\;{\theta}\;{\leq}\;10^{\circ}$). Experimental observations for nearly horizontal data group show that the flow is not fully developed due to the water level gradient and the hydraulic jump within the channel. For the inclined channel data group, a dimensionless wave height, $\Delta$h/h, is empirically correlated in terms of $Re_{G}$ and h/H. A modified root-mean-square wave height is proposed to consider the effects of the interfacial and wave propagation velocities. It is found that an equivalent roughness has a linear relationship with the modified root-mean-square wave height and its relationship is independent of the inclination.

• Journal of the Semiconductor & Display Technology
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• v.7 no.4
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• pp.35-39
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• 2008

We studied deposition of low-k SiOCH dielectric film by PECVD. DEMS(diethoxymethlysilane) precursor, which has two ethoxy groups along with one methyl group attached to the silicon atoms, was used as precursor. The SiOCH film was deposited as a function of oxygen flow rates ranging from 0 to 100sccm. The deposition rate($\AA$/min) of SiOCH film was increased due to the increase of oxygen radical as a function of $O_2$ flow rates. The dielectric constant was decreased from 3.0 to 2.77, as the film was annealed at $450^{\circ}C$ for 30 min. So, it could account that the dielectric constant changes sensitively with $O_2$ flow rates. Also, the leakage current of the annealed film exhibited stable curve than that of asdeposited. These results were caused by the increase of Si-O-Si group and decrease of Si-CH group and OH group within the film by annealing.

• Proceedings of the Korean Institute of Landscape Architecture Conference
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• 2007.10b
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• pp.214-219
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• 2007

Psychological and physiological effects of plants were studied by investigating human responses while observing plants. Eighteen healthy adult male(aged between $19{\sim}25$ years) participated in this study. Semantic differential method(SD method) and multi-channel near-infrared spectroscopy(NIRS) were used to survey verbal and non-verbal response, respectively. Cerebral hemodynamics as a new evaluation index of brain activity was recorded for right brain hemisphere where visual information is mainly delivered. Thirty seconds of cerebral blood flow in forty seven channels were calculated when watching five types of picture images with different rates of hedge against gray block wall; 0:10, 3:7, 5:5, 7:3, 10:0. In the SD results, similar evaluations were found in all subjects. However, the change of cerebral hemodynamics as a non-verbal response varied among subjects. Largely two patterns of hemodynamics change were found with increasing plants rate in picture images; group A showed significant decreases of blood flow volume in many cortical regions, Group B had significant increase of blood flow volume in the occipital region for the scenes seen comparatively more plant. Our findings on the cerebral hemodynamics may indicate that there are two patterns of brain activity during observation of plants; group A in which brain areas associated with visual information and thinking work simultaneously to the visual stimuli; group B in which brain areas associated only with visual information work.

• YAKHAK HOEJI
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• v.44 no.2
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• pp.149-154
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• 2000

Flavin mononucleotide (1,4-butanediamine) Pt(II) complex (7FMN) was synthesized and screened anticancer activity [J. Pharm. Soc. Korea 43(6),762-770 (1999)]. 7FMN have good water solubility and moderate anticancer activiy In this paper cell-cycle specificity and nephrotoxicity were studied. Interaction of DNA with cisplatin and synthesized 7FMN was analyzed by flow cytometry and showed G2 arrest in L1210 cell line. It means that cell-cycle on L1210 was inhibit in S phase by cisplatin and 7FMN. In order to biochemically analyze nephrotoxicity of cisplatin and 7FMN, after injecting each agent intraperitoneally, blood was exsanguinated after 6 hours, 1 day, 3 days and 7 days, respectively. Then, serum was separated from the blood. The serum level of BUN, creatinine and uric acid in cisplatin and 7FMN administated mice (25~35 g, ICR strain, a dose each 8,12 and 16 times of the $IC_{50}$/ value, cisplatin; 7 times) were determined by autochemistry analyzer. In cisplatinadministered mice group, BUN level was elevated than normal control group at 3rd day and repaired at 7th day. In 7FMN administrated group was not elevated. Creatinine and uric acid level were no difference with the normal control group. Therefore synthesized 7FMN is less toxic than cisplatin in nephrotoxiciaty.

• Journal of Families and Better Life
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• v.32 no.5
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• pp.125-143
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• 2014

The purpose of this study was to gain a better understanding of households with a negative cash flow. The Household Budget Survey conducted in 2000, 2005, and 2010 by the Bureau of Statistics in South Korea were used for this study. The households used in this study were divided into four groups according to their income levels; they were categorized the lowest, low, middle, and high income groups. This study made several findings regarding households with a negative/positive cash flow. Firstly, the demographic and economic characteristics were different between those who have a negative cash flow and those with a positive cash flow. A female household head, a household head age 65 and older, a household head with a lower educational attainment, an unemployed household head, and the presence of a child/children in schools were related with the household deficit. Secondly, the households with a positive cash flow had a higher income level compared to the households with a negative cash flow, while the households with a negative cash flow had a much higher consumption level compared to the households with a positive cash flow. Thirdly, the household deficit to total income ratio of the lowest income group was higher when compared to any other income group. Lastly, the multivariate statistics showed that households including a child/children in schools are more likely to be a household with a negative cash flow. Especially, the expenditures on education and transportation were related with the likelihood of a household deficit.