• Journal of Korea Water Resources Association
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• v.35 no.6
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• pp.737-751
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• 2002

Water quality in Daechung Lake was predicted for various discharge conditions of Yongdam dam. The same scenarios were applied as in the previous paper by the authors for Keum River water quality modeling. Effects in water quality due to changes in discharge conditions from Yongdam Dam were less distinct to the Daechung Lake than to the inflowing Keum River due to sink processes in the lake. For the minimum flow year, it is appropriate to maintain Yongdam dam discharge rate to 8.9 $m^3$/sec considering the current field conditions and future predictions of TN and TP concentrations of Yongdam dam. Effect of Yongdam dam discharge conditions to the Daechung Lake water quality were stronger for drier years. However it should be noted that the effects were dependent upon the water quality of Yongdam discharge at the same time. Therefore, water quality management effort should be emphasized before the discussion over the discharge volume of Yongdam dam. The input data sets for simulations in this study were formulated using the available data and assumptions based on authors experiences for the fields. Therefore, continued data collection effort will ensure the validity of this study.

• Korean Journal of Materials Research
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• v.7 no.3
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• pp.196-202
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• 1997

Perovskite lanthanum doped lead titanate ($(Pb,La)TiO_{3}$ or PLT) thin films were successfully fabricated on Pt/TijSiO.iSi substrates at the temperatures as low as $440~500^{\circ}C$ by eleclron cyclotron resonance plasma-enhanced chemical vapor deposition (ECR PECVII). Since the volatilities of the MC sources arid oxide molecules (especially Ph oxide) increased with increasing deposition temperature, the film deposition rate and the (I'b + La)/'Ti ratio decreased Stoichiometric perovskite PL'T films with good dielectric and leakeage current properties were obtained at the temperatures of $460~480^{\circ}C$. The lanthanum content of the film was nearly directly propotional to $La(DPM)_{3}$ flow rate. As the La/Ti ratio increased from 3.0 to 9.5%, the dielectric constant increased from 360 to 650 and the leakeage current density at 100kV/cm electric field decreased from $4{\times}10^{-5}$ to $4{\times}10_{-8}A/cm^2$.

• Fire Science and Engineering
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• v.31 no.5
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• pp.63-69
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• 2017

This study describes the development of a long-distance hose for ultra-high pressure operation, which can be used in conjunction with an ultra-high pressure pump and can be effectively applied to the fire suppression of high-rise buildings and a long, large tunnels. Also, it has phosphorescent properties, which can help to secure the withdrawal route of the fire-fighters when they are threatened by the fire. We developed an ultra-high pressure hose aiming at a pressure of 3 MPa and a flow rate of 2000 lpm and developed an ultra-high pressure fire hose that can withstand this very high pressure by using a double jacket, triple polyurethane coating and warf (Wp) of 52. In order to ensure the performance of the developed ultra-high pressure hose, its structure, appearance, leakage at high pressure, length and elongation were inspected by a certified certification agency, who also subjected it to a peeling test, friction test, breaking pressure test and free fall test. Also, it was studied in addition to the luminescent high-pressure hose for fire-fighting. In the phosphorescence test, the luminance measurement value was more than the reference value of the luminance test after 40 minutes, which confirmed that its performance was satisfactory for fire-fighting products. In the future, if such an ultra-high pressure fire hose were commercialized and applied in the field, it could contribute to securing improved fire suppression and safer exit from fires, as compared to the fire hoses currently used in the suppression of fires in skyscraper buildings and long tunnels.

• Fire Science and Engineering
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• v.32 no.3
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• pp.42-50
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• 2018

The effect of sub-grid turbulence and combustion models on the mean flame height in a heptane pool fire according to the Fire Dynamics Simulator (FDS) version (5 and 6) based on Large Eddy Simulation (LES) was examined. The heat release rate for the fire simulation was provided through experiments performed under identical conditions and the predictive performance of the mean flame height according to FDS version was evaluated by a comparison with the existing correlation. As a result, the Smagorinsky and Deardorff turbulence models applied to FDS 5 and 6, respectively, had no significant effects on the mean flow field, flame shape and flame height. On the other hand, the difference in pool fire characteristics including the mean flame height was due mainly to the difference in the mixture fraction and Eddy Dissipation Concept (EDC) combustion models applied to FDS 5 and 6, respectively. Finally, compared to FDS 6, FDS 5 provided the predictive result of a significantly longer flame height and more consistent mean flame height than the existing correlation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4460-4467
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• 2010

Recent advances in computer technology have brought more dependence on software to railway systems and changed to computer systems. Hence, the reliability and safety assurance of the vital software running on the embedded railway system is going to tend toward very critical task. Accordingly, various software test and validation activities are highly recommended in the international standards related railway software. In this paper, we presented an automated analysis tool and standard for software testing coverage in railway system, and presented its result of implementation. We developed the control flow analysis tool estimating test coverage as an important quantitative item for software safety verification in railway software. Also, we proposed judgement standards due to railway S/W Safety Integrity Level(SWSIL) based on analysis of standards in any other field for utilizing developed tool widely at real railway industrial sites. This tool has more advantage of effective measuring various test coverages than other countries, so we can expect railway S/W development and testing technology of real railway industrial sites in Korea.

• Journal of the Korean GEO-environmental Society
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• v.16 no.7
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• pp.43-53
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• 2015

More than 70 percent of the Korean territory consists of mountain area so development of mountain district is essential to urbanize continuously. Thus, technological developments for risk factors and standards and manuals must be needed to prevent mountain disaster. Risk Management Manual should be made and operated in government legislation related to national disaster, but there is still no Emergency Management Standard Manual and Emergency Response-Practical Manual to prevent mountain disaster. This study suggests the improvement plans that are legislated but not established cleary in the field of disaster in urban area. The main items are like as 1) adaptable standard and practical manual to prevent mountain disaster in urban area, 2) reinforcement between managing department and interagency vertically and horizontally in central and local government organization, 3) Personal SOP (Standard Operating Procedure) not EOP (Emergency Operation Plan), 4) considering 13 items selected by Ministry of Public Safety and Security, 5) schematization with personal action plan, 6) check list to do in the event of mountain disaster, and 7) regular practice per quarter.

• Journal of Yeungnam Medical Science
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• v.12 no.1
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• pp.96-104
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• 1995

The transarterial embolization has been widely used to control bleeding. It has a variety of clinical utility; to reduce bleeding on the surgical field, to reduce the size of malignant tumor as a preopearative treatment, to treat arteriovenous malformation or arterial aneurysm as a curative method and to promote life quality of patient with diffuse or multiple hepatocellular carcinoma as a palliative treatment, etc. With the advance of modem technology, various embolic materials have been also developed. However, it has not been fully investigated of histopathologic changes of the embolized organs according to the embolic materials used. This study was undertaken to investigate the histopathologic changes of embolized renal artery in rabbit by various embolic materials, according to each embolic material and to time passed by after embolization. Of the 5 arteries embolized by ethylene vinyl alcohol copolymer(EVAL), one showed abscess formation in embolized kidney. The other 4 allowed to perform further pathologic study: within a week after embolization there was no any specific change in vessels, however, minimal endothelial hypertrophy was observed following 2 weeks of embolization. Of the 8 renal arteries embolized by N-buthyl-2-cyanoacrylate(Histoacryl), 4 showed total occlusion of the main renal arteries as well as renal infarction, which reflects the strong adhesiveness of Histoacryl to vascular wall. The other 4 showed fibrinoid degeneration in vascular wall within a week. However, further change was not observed thereafter. In all the 5 renal arteries embolized by polyvinyl alcohol(Ivalon), there were infiltration of inflammatory cells along the vessel walls, within one week, which represents vasculitis. They showed some fibrosis with appearance of giant cells in the vessel wall two weeks after embolization and also showed marked fibrosis of connective tissues surrounding vessels two months after embolization, respectively. The results suggest that EVAL is useful for the embolization of hypervascular lesion with limited arteriovenous fistula, Histoacryl for the curative treatment of the lesion with high blood flow or severe arteriovenous fistula, and Ivalan for palliative treatment of malignant tumor or arteriovenous malformation, respectively.

• Journal of The Geomorphological Association of Korea
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• v.19 no.2
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• pp.31-49
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• 2012

Satae cheon, a tributary of the Suip cheon in Yanggu, Gangwon province, is an international river extended to North Korea. Most of drainage basin area of the river was the fierce battle field during the Korean War(1950-1953) and hard to access as it located between the MDL(Military Demarcation Line) and the CCZ(Civilian Control Zone: about 10km south from MDL). By the restriction of access to the sites, most of natural landscape have been well conserved except limited use for military activities. Even the landfoms in that area were not studied, except the government's heritage reports. Satae Cheon's channel follows the Imdang fault line(N-S) to Satae-ri and flow to west to the Dutayeon area. The river meanders along geological structure or weak line at the Dutayeon area. The meandering channel was shorten by the meander cut which linked the thalweg line of meander loop ant the meander neck. As a result of this cut, the river cliff formed by the Satae cheon became the part of newly formed channel bed and the S-forms are formed. After the channel route stabilized, channel incised the rock with large potholes and undulating walls were formed. The channel width changes from 1m to 10m with restriction of the undulating walls, so this part can be regarded as inner channel or inner gorge. From the point of planar forms it also can be slot-type canyon.

• Korean Journal of Comparative Education
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• v.27 no.3
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• pp.161-184
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• 2017

This study aims to draw implications by analyzing the direction of the reorganization of French teacher policy focusing on ESPE which was introduced in 2013 according to the flow of French education reform. When looking at the major changes in the French teacher training system, three revisions have been made over the last 25 years and starting from IUFM introduced in 1991 and through in 2009, ESPE, a new teacher training institute, has been introduced in 2013 and been running. ESPE is an independent professional teacher training institution for educating teachers (from kindergarten to university) as well as education specialists and the understanding of ESPE has a significance in that it can see the direction of reform of French teacher policy in the fact that all advantages of the former system is succeed at maximum and the disadvantages are complemented. When looking at the major reorganization direction of French teacher policy, first, it has strengthened its position as a research teacher by connecting teacher training with the master's degree program. Second, it pursued the balance between theoretical education and field training in teacher training. Third, eligibility criteria of teacher training become diversified and it's downgrading from master degree to bachelor degree. Fourth, teacher training, teacher recruitment exam, master degree in teaching and teacher certification are linked each other. Fifth, teacher training is made in two aspects, teachers as well as education specialists. In conclusion, French teacher policy has a great significance in terms of the fact that the will of reform improving the quality of education ultimately through establishing the status as research teacher and improving the quality of teachers can be seen.

• Journal of The Korean Association For Science Education
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• v.39 no.4
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• pp.535-544
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• 2019

In order to find out whether the traditional mass media in our society are sufficiently functioning as a vehicle of providing scientific information to the public outside the school education, public perception of science articles in mass media and scientific terms used in high frequency in science articles have been examined. To investigate the public perception on science articles, a questionnaire was constructed about the usefulness, importance, access frequency, and understanding of science articles. The questionnaires were conducted in areas with high flow populations such as train stations or subway stations. A total of 425 responses were used for analysis. In order to extract high frequency scientific terms used in science articles, two television companies and two newspapers were designated as target media, and their texts on science articles reported over the last 17 years were collected to investigate the frequency of scientific terms used. Based on the frequency, we conducted the self-report comprehension test for the top 100 scientific terms. The results of this study show that the public in our society has relatively high perception of the importance and usefulness of science articles, however, reading and understanding the articles seems to be somewhat difficult. In addition, the scientific terminology used in science articles has a high degree of comprehension for those of higher education, natural sciences majors, and men. In addition, scientific terms with high understanding degree were characterized according to gender, age, educational background, and field of major.