• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.114-114
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• 2014

We present our activities linking to planning of possible forms of large program to study on circumstellar H2O and SiO maser sources with KaVA. A great advantage of KaVA for the stellar maser observations is the combination of the unique capability of the multi-frequency phase referencing technique of KVN and the dual-beam astrometry of VERA with the KaVA's relative dense antenna configuration. We have demonstrated this advantage through the test observations conducted by the KaVA Evolved Stars Sub-working Group since 2012 March. Snapshot KaVA imaging is confirmed to be possible in integration time of 0.5 hour at the 22 GHz band and 1.0 hour at the 43 GHz band in typical cases. This implies that large snapshot imaging surveys towards many H2O and SiO stellar masers are possible within a reasonable machine time (e.g., scans on ~100 maser sources within 200 hours). This possibility enables us to select the maser sources, which are suitable for future long-term (10 years) intensive (biweekly-monthly) monitoring observations, from 1000 potential target candidates selected from dual-frequency band (K/Q-bands) KVN single-dish observations. The output of the survey programs will be used for statistical analysis of the structures of individual stellar maser clumps and the spatio-kinematical structures of circumstellar envelopes with accelerating outflows. The combination of astrometry in milliarcsecond(mas) level and the multi-phase referencing technique yields not only trigonometric parallax distances to the masers but also precise position reference for registration of different maser lines. The accuracy of the map registration affects interpretation of the excitation mechanism of the SiO maser lines and the origin of the variety of the maser actions, which are expected to reflect periodic behaviors of the circumstellar envelope with stellar pulsation. Currently we are checking the technical feasibility of KaVA operations for this combination. After this feasibility test, the long-term monitoring campaign program will run as one of KaVA's legacy projects.

• Biomedical Science Letters
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• v.11 no.3
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• pp.281-287
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• 2005

Although actinomycin D (AMD) is known to induce apoptotic cell death to various cell lines, the mechanism of apoptosis induced by AMD is still unclear. Understanding this mechanism may improve its therapeutic efficacy. The present study has been performed to elucidate expression of Bcl-2 and Caspase-3 proteins related to apoptosis in human leukemia K-562 cells. Five different assays were performed in this study; DNA fragmentation analysis by agarose gel electrophoresis, quantitative assay of fragmented DNA, morphological assessment of apoptotic cells, quantification of apoptosis by annexin V (AV) and propidium iodide (PI) staning, and expression of Bcl-2 and Caspase-3 proteins by the western blot analysis. The number of apoptotic cells and amount of fragmented DNA in this cell line treated with AMD was increased at 6 hour. DNA ladder pattern was also appeared at 6 hour. The expression of Bcl-2 was decreased, and disappeared from 12 hours after AMD treatment. Precursor of Caspase-3 was degraded, and 20 kDa cleavage products were detected. These results suggest that AMD induced apoptosis of K-562 cells is Caspase-3-dependent fashion, and this apoptosis is related to the degradation of Bcl-2 proteins.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.1
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• pp.55-70
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• 2001

It was unusual crop weather for 1998 and 1999 compared with normal in Korea. The consecutive days of the optimum ripening period for rice plant that had daily mean temperature 21~23$^{\circ}C$ for 40 days after flowering, increased with long anomalies in 1998~99. The air temperature during ripening period was much higher than the optimum temperature and lower sunshine hour than norm in the local adaptability tests of newly developed rice lines during those years. In response of rice cultivation to warming and cloudy weather during crop season, the yield shall be decreased. Most scientists agree that the rate of heating is accelerating and temperature change could become increasingly disruptive. Weather patterns should also become more erratic. Agrometeorologists could be analyzed yearly variations of temperature, sunshine hour and rainfall pattern focused on transient agroclimate change for last a decade. Rice agronomists could be established taking advantage of real time agricultural meteorology information system for fertilization, irrigation, pest control and harvest. Also they could be analyzed the characteristics of flowering response of the recommended and newly bred rice cultivars for suitable cropping plan such as cultural patterns and sowing or transplanting date. Rice breeders should be deeply considered introducing the characteristics of basic vegetative type of flowering response like Togil rices as prospective rice cultivars corresponding to global warming because of the rices needed higher temperature at ripening stage than japonica rices, photoperiod-sensitive and thermo-sensitive ecotypes.

• The Korean Journal of Applied Statistics
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• v.30 no.5
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• pp.719-731
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• 2017

In September 2010, the Korea government increased the speed limit on the Gyeongbu Expressway (Cheonan IC.-Yangjae IC) from 100 to 110 km per hour. This paper considers ARIMA-Intervention model to analyze the effects of the speed limit change on the incidences of traffic accidents and injuries. In addition, in order to investigate the effects more clearly, we also analyze the difference between the two lines of Cheonan IC-Yangjae IC and Busan IC-Cheonan IC. As a result, we observe that the numbers of accidents and injuries have increased after the speed limit change. The increases are strikingly distinctive in comparison to other lines (Busan IC-Cheonan IC) where there have been no changes in the maximum speed limit.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.81-85
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• 2012

Purpose: To study enhancing effects of paclitaxel in the thermochemotherapy of osteosarcoma cell lines and related mechanisms. Materials and Methods: Paclitaxel and carboplatin were used alone or jointly on OS732 cell lines in the presence of hyperthermia. Inhibition of proliferation was measured by MTT assay and cellular changes were assessed with inverted phase contrast and fluorescence microscopy. Apoptosis was analyzed with flow cytometry (FCM) and Fas expression by immunocytochemistry. Results: At $43^{\circ}C$, one hour after the application of 10ug/ml paclitaxel and $5{\mu}g/ml$ carboplatin on OS732 cells jointly, the survival rate was 15.8% which was significantly lower than with $10{\mu}g/ml$ paclitaxel (45.8%) and $5{\mu}g/ml$ carboplatin (47.7%) respectively (P<0.01). Moreover, changes of morphology and apoptotic rates indicated that the apoptosis-inducing effect of combined application was also much enhanced, as evident also regarding Fas expression. Conclusion: Paclitaxel is conducive to thermochemotherapy of osteosarcoma cell lines, possibly accomplished by up-regulation of Fas expression with induction of apoptosis.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.27 no.1
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• pp.107-122
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• 1997

Radiation sensitivity data was generated for two human cancer cell lines(KB, RPMI 2650) and human primary gingival fibroblast was tested three times using a viable cell number counting with a hemocytometer, MTT(3-[4,5-Dimethylthiazol2-yl]-2,5-diphenyl tetrazolium bromide) assay, and LDH(Lactate dehydrogenase) assay. Single irradiation of 2, 4, 6, 10, 15, 20Gy were applied to the tumor cell lines and the primary cultured gingival fibroblast The two fractions of 4Gy and 10Gy were seperated with a 4 hour time interval. The irradiation was done with 241.5cGy/min dose rate using /sup 137/Cs MK cell irradiator at room temperature. The obtained results were as followed : 1. There was significantly different viable cell numbers as the amount of radiation dose on the tested cells were cell number counted with a hemocytometer. In fractions, there were more viable cells remaining. 2. Phase-contrast microscopically, radiation-induced morphologic changes were pronounced on the tumor cells, however, almost no differences on the gingival fibroblast. 3. There was significantly different absorbance at 2Gy on RPMI 2600, 4Gy on KB and GF in MTT assay. In fractions, the absorbance was significantly higher on KB. 4. The level of extracellular LDH activity in the experimental group was significantly higher in the 2-4Gy than the control group. 5. The total level of extracellular and intracellular LDH activity was decreased as increased amounts of radiation dose was applied.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.6
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• pp.158-169
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• 2004

A method for predicting the short-term dynamic line ratings in overhead transmission lines using real-time weather forecast data is proposed in this paper. Through some inspections for the 3-hour interval forecasting factors such as ambient temperature, wind speed grade and weather code given by KMA(Korea Meteorological Administration), correlation properties between forecast weather data and actual measured data are analyzed. To use these variable in determining the dynamic line ratings, they are changed into suitable numerical values. Furthermore adaptive neuro-fuzzy systems to improve reliabilities for wind speed and solar heat radiation ate designed It was verified that the forecast weather data can be used to predict the line rating with reliable. As a result it can be possible that the proposed predicting system can be effectively utilized by their anticipation a short-time in advance.

• Journal of Industrial Technology
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• v.20 no.A
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• pp.229-238
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• 2000

Simulation analysis for an auto body manufacturing system has been performed in this study. The major goal is to figure out the condition yielding the production rate, 70 per hour. It is, however, very difficult to maintain this rate due to inherent system factors such as machine failure rates, machine repair rates, number of carriers between manufacturing lines(shops), carrier speed etc. We first carefully examined the system and developed a simulation model using ARENA. We then applied statistical experimental design concepts for performance analysis. Our results indicate that the buffer size of 30 and quick repair of failed robots are required for the desired production rate. Other factors, on the other hand, are seen to have minor effects on the throughput. The approach taken in this study and the results obtained may provide a practical guideline for performance analysis and thus be applied without trepidation for similar cases.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.644-647
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• 2003

This paper describes a neural network based machine vision system designed for inspecting yellow beans in real time. The system consists of a camera. lights, a belt conveyor, air ejectors, and a computer. Beans are conveyed in four lines on a belt and their images are taken by a monochrome line scan camera when they fall down from the belt. Beans are separated easily from their background on images by back-lighting. After analyzing the image, a decision is made by a multilayer artificial neural network (ANN) trained by the error back-propagation (EBP) algorithm. We use the global mean, variance and local change of gray levels of a bean for the input nodes of the network. In an our experiment, the system designed could process about 520kg/hour.

• Journal of the Korean Society for Heat Treatment
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• v.20 no.6
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• pp.306-310
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• 2007

Changes in microstructure and damping capacity with aging time for solutionized Mg-Al alloy have been investigated. Discontinuous ${\beta}\;(Mg_{17}Al_{12})$ precipitates form along the primary grain boundaries, the amount of which increases as the aging time increases. The hardness of the matrix with respect to aging time shows a typical "S" shape, indicating a generation of fine continuous precipitates in the matrix during the aging. The peak level of damping capacity is obtained after 1 hour of aging, over which the damping capacity becomes deteriorated continuously. The formation of optimum density of continuous ${\beta}$ precipitates with fine morphology which would act as pinning points for dislocation lines, might be responsible for the improvement of damping capacity.