• The Journal of Korean Association of Computer Education
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• v.16 no.6
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• pp.1-10
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• 2013

Until now, the study of Internet addiction have focused on (1)Internet overuse (2)addiction (3)the real situation of disability in order. This approach have given a social awareness about Internet addiction as well as have been used as base for introduction of psychological and emotional means to prevent and treat Internet addiction. However, There are very few an ethical approach that is related in human values that what purpose does people use Internet for and how to use Internet. Accordingly, This study provides teleological, deontological, virtue and responsible ethics of Internet addiction. And, this study insist that Internet addiction is a wrongdoing on the basis of four ethical views. Based on these claims, this study stress the needs for Internet ethical education as a program to prevent and treat Internet addiction and se to tu1rn pop1 computer ethics into theoretical computer ethics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.04b
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• pp.7-7
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• 2009

Lead telluride (PbTe) is a very promising thermoelectric material due to its narrow band gap (0.31 eV at 300 K), face-centered cubic structure and large average excitonic Bohr radius (46 nm) allowing for strong quantum confinement within a large range of size. In this work, we present the thermoelectric properties of individual single-crystalline PbTe nanowires grown by a vapor transport method. A combination of electron beam lithography and a lift-off process was utilized to fabricate inner micron-scaled Cr (5 nm)/Au (130 nm) electrodes of Rn (resistance of a near electrode), Rf (resistance of a far electrode) and a microheater connecting a PbTe nanowire on the grid of points. A plasma etching system was used to remove an oxide layer from the outer surface of the nanowires before the deposition of inner electrodes. The carrier concentration of the nanowire was estimated to be as high as $3.5{\times}10^{19}\;cm^{-3}$. The Seebeck coefficient of an individual PbTe nanowire with a radius of 68 nm was measured to be $S=-72{\mu}V/K$ at room temperature, which is about three times that of bulk PbTe at the same carrier concentration. Our results suggest that PbTe nanowires can be used for high-efficiency thermoelectric devices.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.5
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• pp.612-624
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• 2007

The real-time monitoring of radon ($^{222}Rn$) concentrations has been carried out to evaluate its ambient background concentration levels in Gosan site, Jeju Island between January 2001 and December 2004. In addition, the atmospheric TSP aerosols have been sampled, and their ionic and metallic components were analyzed to understand the characteristics of air pollution. The mean concentration of radon was $3,121{\pm}1,627\;mBq/m^3$, and the seasonal mean concentrations for spring, summer, fall and winter seasons were 2,898, 2,398, 3,571 and $3,646\;mBq/m^3$, respectively, The hourly concentrations have shown the highest value at 7 a.m. and the lowest value at 2 p.m. From the backward trajectory analyses, the radon concentrations have increased, when the air parcels were moved from the Chinese continent to Jeju area. On the other hand, they have decreased, when the air parcels from the North Pacific Ocean. In the analytical results of ionic species and metal elements of TSP aerosols, the concentrations of $nss-{SO_4}^{2-}$ and S were higher in June and March. Meanwhile, the concentrations of other anthropogenic species as well as soil components were mostly higher in March and April. On the basis of factor analysis, the TSP aerosols at Gosan area were largely influenced by soil sources, followed by anthropogenic sources and marine sources. From the result of backward trajectory analyses, the concentrations of $nss-{SO_4}^{2-},\;{NO_3}^-$, Al and Ca were mostly higher, when the air parcels moved from Chinese continent to Jeju area. On the other hand, their concentrations were lower, when the air parcels drifted from the North Pacific Ocean.

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.2
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• pp.174-183
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• 2017

The background level and timely variation characteristics of atmospheric $^{222}Rn$ concentrations have been evaluated by the real time monitoring at Gosan site of Jeju Island, Korea, during 2008~2015. The average concentration of atmospheric radon was $2,480mBq\;m^{-3}$ for the study period. The cyclic seasonality of radon was characterized such as winter maximum and summer minimum, consistent with the reduction in terrestrial fetch going to summer. On monthly variations of radon, the mean concentration in October was the highest as $3,041mBq\;m^{-3}$, almost twice as that in July ($1,481mBq\;m^{-3}$). The diurnal radon concentrations increased throughout the nighttime approaching to the maximum ($2,819mBq\;m^{-3}$) at around 7 a.m., and then gradually decreased throughout the daytime by the minimum ($2,069mBq\;m^{-3}$) at around 3 p.m. The diurnal radon cycle in winter showed comparatively small amplitude due to little variability in atmospheric mixing depth, conversely, large amplitude was observed in summer due to relatively a big change in atmospheric mixing depth. The cluster back-trajectories of air masses showed that the high radon events occurred by the predominant continental fetch over through Asia continent, and the radon concentrations from China continent were about 1.9 times higher on the whole than those from the North Pacific Ocean. The concentrations of $PM_{10}$ also increased in proportion to the high radon concentrations, showing a good linear correlation between $PM_{10}$ and radon concentrations.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.4
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• pp.707-715
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• 2010

In this study, meridian massage is developed and applied on post menopausal Women with Hemodialysis to identify the effects of Menopausal Symptoms, Mood, Estradiol($E_2$), and Pain. The study was a nonequivalent control group pre-post test Quasi-experimental design. There were 17 people in the experimental group and 17 people in the control group. Meridian massage was performed for 4 weeks, 3 times a week for 20 minutes each sessions. The data were collected at pretest and posttest. SPSS win. 11.5 program was used. Fisher's exact test and Mann Whitney U-test were used to analyze the Pre-treatment homogeneity. Wilcoxon Sign Rank test was used to find out the effectiveness within each groups. Mann Whitney U-test was used in comparing between the two groups. After meridian massage, there were significant differences in menopausal symptoms in experimental group(z=-2.583, p=.010) and pain between groups(U=86.00, p=.040). $E_2$ was not effective in both groups. The mood was effective in both groups, since the mood had influenced by interviewer's collecting data. Meridian massage was effective in alleviating menopausal symptoms and pain of post menopausal women with Hemodialysis, but it is desirable to perform meridian massage to the patients for enough time.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.2
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• pp.221-230
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• 1997

In hydrology analysis, the result of a slope analysis for terrain have an very important effect on water quality and water quantity Recently, a slope analysis tend to use the digital elevation model rater than the traditional map sheet. But a terrain slope analysis by the digital elevation model depends on grid size of the digital elevation model. Hence the effect of a slope analysis by the digital elevation model is a important factor. In this study, therefor, in order to determine a hydrological parameter and a terrain parameter for simulation of the water quality and the hydrological property, we adapted two sample area that are the Nerin stream of the basin of the Soyang lake and a Osip stream of Samchuk, and its individual coverages are $640\;km^2$ and $33\;km^2$. Also to analyze the effect of grid size in the slope of a basin, we apply DEM changing a grid size respectively at intervals of 100 m from 100 m to 1.000m for the Nerin stream basin and at intervals of 10 m from 20 m to 300 m for the Osip stream basin.

• Magazine of the Korean Society of Agricultural Engineers
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• v.35 no.1
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• pp.50-58
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• 1993

The sedimentation patterns at a reservoir, important to the reservoir capacity curve were simulated using a depth averaged, two-dimensional sediment transport model, that is capable of depicting velocity distributions and sediment transportation. The Banweol reservoir, whose stage capacity relationships have been surveyed before and after the construction, was selected and the daily inflow rates and stages were simulated using a reservoir operation model(DI-ROM). The applicability of the transport model was tested from the comparisons of simulated sedimentation patterns to the surveyed results. The simulated inflow rates and water level fluctuations at the reservoir during twenty-one years from 1966 to 1986, showed that water levels exceeding 80 percent of the total capacity occurred for 70 percent of the periods and inflow rates less than 5000rn$^3$/day sustained for 54 percent of the spans. Dorminant flow directions were simulated from two streamflow inlets to the dam site. And simulated sediment concentrations were higher near the inlets and lower at the inside of the reservoir. Sediment was deposited heavily near the inlets, and portions of sediments were distributed along the flow paths within the reservoir. The comparisons between the simulation results and the surveyed depositions were partially matched. However, it was not possible to compare two results at the upper parts of the reservoir where dredging was carried out few times for the purpose of reservoir maintenance. This study demonstrates that sedimentation patterns within the reservoir are closely related to incoming sediment and flow rates, water level fluctuations, and flow circulation within the reservoir.

• Journal of Soil and Groundwater Environment
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• v.16 no.6
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• pp.133-142
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• 2011

A total of 247 samples were collected from groundwater being used for drinking-water supply, and hydrogeochemistry and radionuclide analysis were performed. In-situ analysis of groundwaters resulted in ranges of $13.7{\sim}25.1^{\circ}C$ for temperature, 5.9~8.5 for pH, 33~591 mV for Eh, $66{\sim}820{\mu}S/cm$ for EC, and 0.2~9.4 mg/L for DO. Major cation and anion concentrations of groundwaters were in ranges of 0.5~227.6 for Na, 1.0~279.3 for Ca, 0.0~9.3 for K, 0.1~100.1 for Mg, 0.0~3.3 for F, 0.9~779.1 for Cl, 0.3~120.4 for $SO_4$, 0.0~27.4 for $NO_3$-N, and 6~372 mg/L for $HCO_3$. Uranium-238 and radon-222 concentrations were detected in ranges of N.D-$131.1{\mu}g/L$ and 18-15,953 pCi/L, respectively. In case of some groundwaters exceeding USEPA MCL level ($30{\mu}g/L$) for uranium concentration, their pH ranged from 6.8 to 8.0 and Eh showed a relatively low value(86~199 mV) compared to other areas. Most groundwaters belonged to Ca-(Na)-$HCO_3$ type, and groundwaters of metamorphic rock exhibited the highest concentration of Na, Mg, Ca, Cl, $NO_3$-N, U, and those of plutonic rock showed the highest concentration of $HCO_3$, and Rn. Uranium and fluoride from granite areas did not show any correlation. However, uranium and bicarbonate displayed a positive relation of some areas in plutonic rocks($R^2$=0.3896).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.2
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• pp.94-104
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• 2020

An ecological study for species composition and abundance of the fish assemblages in the coastal waters of Gujora and Mangchi of Geoje, Korea was conducted using monthly larval collection by an RN80 net from June, 2018 to May, 2019. A total of the 5 Orders, 15 Families, 21 species were collected. The dominant species were Ammodytes japonicus and Engraulis japonicas. Gobiidae was the most dominant species in June, Spratelloides gracilis in July, Chelidonichthys sp. in August, Gobiidae in September, Repomucenus beniteguri in October, Sebastiscus marmoratus in November, Sebastiscus marmoratus and Hexagrammos otakii in December of 2018, Pleuronectes yokohamae in January, Ammodytes japonicus in Febraury, Engraulis japonicus in March, Sebastes sp. and Gobiidae in April and Engraulis japonicus in May of 2019. The highest number of species and individuals were found in July and the smallest in August. Thus, the diversity index was the highest in July and the lowest in August. As a result of the similarity by month was divided into Group I in January and February and Group II in April, June and September. The most dominant species in the Group I were the Ammodytes japonicus and Sebastes inermis, and the most dominant species in the Group II was Gobiidae.

• Ocean and Polar Research
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• v.27 no.4
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• pp.463-476
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• 2005

Mesozooplankton samples were collected to investigate the spatial distribution in the Chuuk lagoon of the Federated States of Micronesia through three surveys from 2002 to 2004. Average temperature was $28.70^{\circ}C$ in August 2002, $30.17^{\circ}C$ in October 2003 and $29.18^{\circ}C$ in July 2004 at a water depth of 2rn. Average salinity was 33.95 psu in August 2002, 33.56 psu in October 2003 and 33.77 psu in July 2004. Total rnosozooplankton consisted of 70 taxa during the study period, among which copepods were the most diverse group. Foraminiferans, radiolarians, copepods and appendicularians, which comprised about 70% of total zooplankton abundance, were important components in the zooplankton community. Within the copepod group, Acartia spp., Centropages spp. and Undinula spp. were dominant in August 2002, Acartia spp., Centropages spp., and Oithona spp. in October 2003, and Acartia spp., Undinula spp., and Oithona spp. in July 2004. Total zooplankton abundance was high around Weno Island, while low in stations located in the northern part of Weno Island. High abundances of appendicularians were found in the southern part of weno Island as well as around Weno Island. Appendicularians foraminiferans, radiolarians, Sagitta spp. and immature copepods accounted for most of the distribution pattern of the mesozzoplankton community throughout the study area. These results suggest that appendicularians may be potential food items for fish larvae around Weno Island in the Chuuk lagoon states.