• Progress in Medical Physics
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• v.20 no.3
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• pp.167-173
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• 2009

As the radiotherapy technique development, the needs for using of medical electronic chart in the department of radiation oncology is growing. However, the complexity of affairs of radiation oncology make it difficult to develop a electronic medical chart. In this study, we introduce the electronic medical chart developed by domestic hospital. The function and example of electronic medical chart designed as radiation treatment progress was showed and the future study was presented.

• Journal of Environmental Science International
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• v.15 no.8
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• pp.727-735
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• 2006

In this study, the PHYTO-PAM-fluorometric method was used to evaluate the ETR$_{max}$ in terms of sensitivity to DIN/DIP against 14 microalgae: Prorocentrum micans, Heterocapsa triquetra, Gymnodinium impudicum, Cymnodinium catenatum, Amphidinium caterae, Chlorella vulgaris, Chroococcus minutus, Microcystis aeruginosa, Chlorella ellipsoidea, Nannochloris oculata, Oocystis lacustris, Chroomonas salina, Gloeocystis gigas, and Prymnessium parvum. We found that P. micans, H. triquetra, and A. caterae exposed to the maximum level of DIN/DIP were significantly smaller in the ETR$_{max}$ than that of the minimum and moderate mixture. Unlikely the ETR$_{max}$, the initial slope alpha was not significantly different at the level of 60 DIN/DIP. In G. catenatum, the moderate levels of 15 and 20 in DIN/DIP were found to be significantly different from the ETR$_{max}$ at Chl-Ch4. Gymnodinium impudicum had a higher value than that of the ETR$_{max}$ than that of dinoflagellates used in this study, ranging from 306.1 (Ch4, DIN/DIP: 10) to 520.1 (Ch4, DIN/DIP: 30). The ETR$_{max}$ value obtained from other microalgae was similar to C. impudicum at any of the ratios of DIN/DIP and channels. Consequently, the influence of offshore water current assures us of the suppression of photosynthesis and electron transport rate in dinoflagellates. Gymnodinium impudicum has not been researched in the area of red tides in Korea, but it will be enough to creat the massive algal blooms in the future because of higher potential photochemical availability.

• Journal of Environmental Science International
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• v.16 no.7
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• pp.799-804
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• 2007

Oil spill caused severe effects on the marine fauna and flora due to direct contact of organisms with the oil and even in regions not directly affected by the spill. This study was conducted to understand the effects of the oil spill accidents and the use of dispersant on the red tide of Cochlodinium polykrikoides. Crude oil produced in Kuwait, bunker-C, kerosene and diesel oil, and a chemical dispersant produced in Korea, were added with a series of 10 ppb to 100 ppm in the f/2-Si medium at $20^{\circ}C$ under a photon flux from cool white fluorescent tubes of $100\;mol\;m^{-2}\;s^{-1}$ in a 14: 10 h L:D cycle for the culture of C. polykrikoides. In low concentrations of ${\leq}$ 1 ppm of examined oils no impact on the growth of C. polykrikoides was recorded, while in high concentration of ${\geq}$ 10 ppm, cell density was significantly decreased with the range of 10 to 80% in comparison with the control. The growth of C. polykrikoides after the addition of the dispersant and the mixtures combined with oils and a dispersant of ${\geq}$ 10 ppm appeared to decrease, whereas the growth of C. polykrikoides exposed to ${\leq}$ 100 ppb showed little serious impact. However, almost all the C. polykrikoides cells were died regardless of a dispersant and combined mixtures within a few days after the addition of high concentrations.

• Journal of Environmental Science International
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• v.16 no.10
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• pp.1119-1125
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• 2007

We examined the horizontal distribution of salinity and the concentrations of DIN and DIP after heavy rain-fall events in coastal areas of South Korea from Yeoja Bay to Narodo and from Gwangyang Bay to Geomodo to determine whether fresh water actually flows into areas of Cochlodinium polykrikoides red tides and to observe its effect on the growth of this organism after heavy rainfall. Following heavy rainfall (155 mm) in the Yeosu and Suncheon regions, the average salinity was 21 and 29 psu at Yeoja Bay and in the coastal waters of Narodo, respectively. After 126 mm of rainfall, the values were 19 and 25 psu in the coastal waters of Yeosu and Geomodo, respectively. This may have been caused by an influx of fresh water, after the rainfall event, into the open sea coastal areas around Narodo and Geomodo from the Dong and Seomjin Rivers, which are about 3540 km away. After the rainfall, the concentrations of $NH_4-N,\;NO_2-N$, and $PO_4-P$ were slightly increased; however, the concentration of $NO_3-N$ was greatly increased and diffused throughout the coastal areas of Narodo and Geomodo, which frequently experience C. polykrikoides blooms. The influence of $NH_4-N,\;NO_2-N$, and $PO_4-P$ on the occurrence of C. polykrikoidesred tides in coastal areas around Narodo and Geomodo after heavy rainfall does not appear to be great. Instead, the occurrence C. polykrikoides red tides in the coastal areas of Narodo and Geomodo seems to be facilitated by $NO_3-N$.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.31 no.3
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• pp.59-70
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• 2023

In order to predict low-level wind shear at Incheon International Airport (RKSI), a Low-Level Wind Shear prediction system (KMAP-LLWS) along the runway take-off and landing route at RKSI was established using Korea Meteorological Administration Post-Processing (KMAP). For the performance evaluation, the case of low-level wind shear cases calculated from Aircraft Meteorological Data Relay (AMDAR) from July 2021 to June 2022 was used. As a result of verification using the performance evaluation index, POD, FAR, CSI, and TSS were 0.5, 0.85, 0.13, and 0.34, respectively, and the prediction performance was improved by POD, CSI, and TSS compared to the Low-Level Wind Shear prediction system (LDPS-LLWS) calculated using the Korea Meteorological Administration's Local Data Assimilation and Prediction System (LDAPS). This means that the use of high-resolution numerical models improves the predictability of wind changes. In addition, to improve the high FAR of KMAP-LLWS, the threshold for low-level wind shear strength was adjusted. As a result, the most effective low-level wind shear threshold at 8.5 knot/100 ft was derived. This study suggests that it is possible to predict and respond to low-level wind shear at RKSI. In addition, it will be possible to predict low-level wind shear at other airports without wind shear observation equipment by applying the KMAP-LLWS.

• Journal of the Korean Geosynthetics Society
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• v.8 no.3
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• pp.45-52
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• 2009

The use of geogrid-reinforced earth wall technologies has progressed rapidly over the past 10 years in Korea because these technologies have advantages such as economical efficiency, graceful appearance, and easy construction. The geogrid used in the reinforced earth wall with concrete block facing can be subjected to damage among the upper and lower blocks and at the interface between the block and the geogrid. Therefore, when design of the geogrid-reinforced soil walls the required connection strength of the geogrid to the wall facing is an issue. In this study, new connection system between facing block and geogrid is developed to improve the damages of geogrid in the existing connection systems. The new connection devices are made of steel and have I-shape. This paper describes the test method and results of the laboratory testing for determination of connection strength in connection system using the I-type connection device.

• Journal of the Korean Geosynthetics Society
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• v.9 no.4
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• pp.75-84
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• 2010

In this study, the long-term performance tests, which have extensibility, creep deformation, installation resistance and durability characteristic, is conducted to apply geosynthetic strip in field. The strength reduction factors using the test results are evaluated in order to calculate long-term design tensile strength. First, the creep deformation was evaluated by both the stepped isothermal method(SIM) and the time-temperature superposition(TTS) method. The creep reduction factor is reasonable to apply 1.6. Second, the result of installation damage test had little damage of yarn, which affected strength of reinforcement. Therefore, it can be analyzed that the installation damage of geosynthetic strip has little effect of long-term design tensile strength. Finally, the durability reduction factor considering chemical, biological and outdoor exposure resistance is reasonable to apply 1.1, which is considered the stability and economic efficiency of reinforced earth wall using geosynthetic strip.

• Journal of the Korean Geosynthetics Society
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• v.11 no.4
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• pp.37-44
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• 2012

This paper describes large scale pullout test results, in order to evaluate extensibility effect of strip-type reinforcement. The same test for ribbed steel strip reinforcement also is conducted to compare the friction resistance reinforcements' evaluation results. The pullout resistance of the ribbed steel strip reinforcement, which has a small cross sectional areas, was better than the friction resistance reinforcements' due to the bearing (passive) resistance. In case of friction resistance reinforcements, the pullout resistance of extensible reinforcement was better than inextensible reinforcement' even though they have a similar cross sectional areas.

• Journal of the Korean Geosynthetics Society
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• v.5 no.1
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• pp.9-14
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• 2006

The reinforced soil retaining wall structures of serious types with environmental are widely expanding more and more in Korea, which divided conventional type's reinforced soil retaining wall on segmental retaining wall. The causes of most crack occurred at block in reinforced soil retaining wall structure caused by the differential settlement of foundation. It is difference of settlement for significant factor that with overall slope stability. In this study, design assessment of foundation bearing capacity related to differential settlement of foundation ground was considered. And, also, through case study, the countermeasure methods and its application were suggested that the bearing capacity of foundation had to stabilize. The foundation ground in charge of bearing capacity should be affected by the resisting force of sliding, because the foundation parts of reinforced soil retaining wall were belongs to potential slope sliding area in overall stabilizing including retaining wall structures. Therefore, the analyzing or the designing of bearing capacity for foundation should be considered control capacity on the overall slope sliding.

• Journal of the Korean Geosynthetics Society
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• v.4 no.2
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• pp.47-56
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• 2005

Recently, geosynthetic reinforced earth walls are gradually replacing conventional concrete retaining walls for reasons of economy, expediency of construction, and aesthetics. A number of reinforced soil walls having more than 10m heights have been constructed to make more effective development in the country. However, mistakes in design and construction of reinforced earth walls have resulted in many troubles such as failure of reinforced earth walls, horizontal deformationor breakdown of facings, and so forth during or after construction. In this paper, a case study on global sliding failure of a geogrid-reinforced tiered wall is carried out to investigate the causes of the failure and suggest the proper countermeasures. From the subsurface investigation and field instrumentation, It is found that the cause of the global sliding failure was occurred by decreasing of bearing capacity of foundation ground induced by infiltration of rainwater.