• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.220-220
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• 2009

In case of favourable irradiation conditions, the ratio of irradiation to the total irradiation went up and then the irradiation increased in the area with high angle of inclination. The study showed that on a clear day with the irradiation of more than $800[W/m^2]$, the pattern of alternating current power change in the fixed system was similar with that in the single-axis tracker. On the contrary, in case of unfavourable irradiation conditions, the ratio of diffuse irradiation to the total irradiation went up and then the horizontal irradiation increased. In the demo system, the fixed system, the single-axis tracker and the dual-axis tracker all had low generation power and similar generation pattern with each other. The study showed the generation power varied with the irradiation in the fixed system, while in the single-axis tracker and the dual-axis tracker, the amount of the generation power variation was much more than the irradiation variation. The demo system was operated from 11:00 AM to 2:00 PM for generating power, during which time, 46[%] to 56[%] of the total generation power was produced. In this study. the generation power was increased by 147[%] in the fixed system, by 136[%] in the single-axis tracker, and by 164[%] in the dual-axis tracker, and the pattern of generation power was similar with the generation power variation in the situation where the irradiation increased by 140[%] in the spring with plenty of insolation. The alternating current power was more sensitive to variation of the irradiation than to that of the surface temperature of a module. The variation of the irradiation had a more positive effect on the generation power than the type of array.

• Proceedings of the KIEE Conference
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• 2009.04a
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• pp.43-45
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• 2009

In case of favourable irradiation conditions, the ratio of irradiation to the total irradiation went up and then the irradiation increased in the area with high angle of inclination. The study showed that on a clear day with the irradiation of more than 80$[W/m^2]$, the pattern of alternating current power change in the fixed system was similar with that in the single-axis tracker. On the contrary, in case of unfavourable irradiation conditions, the ratio of diffuse irradiation to the total irradiation went up and then the horizontal irradiation increased. In the demo system, the fixed system, the single-axis tracker and the dual-axis tracker all had low generation power and similar generation pattern with each other. The study showed the generation power varied with the irradiation in the fixed system, while in the single-axis tracker and the dual-axis tracker, the amount of the generation Power variation was much more than the irradiation variation. The demo system was operated from 11:00 AM to 2:00 PM for generating power, during which time, 46[%] to 56[%] of the total generation power was produced. In this study, the generation power was increased by 147[%] in the fixed system, by 136[%] in the single-axis tracker, and by 164[%] in the dual-axis tracker, and the pattern of generation power was similar with the generation power variation in the situation where the irradiation increased by 140[%] in the spring with plenty of insolation. The alternating current power was more sensitive to variation of the irradiation than to that of the surface temperature of a module. The variation of the irradiation had a more positive effect on the generation power than the type of array.

• Journal of Institute of Convergence Technology
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• v.7 no.1
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• pp.11-14
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• 2017

At present, the Korea Meteorological Administration (KMA) measures the horizontal solar irradiation with time in 33 areas. Among these measured data, this study analyzed the tendency of applying the new analysis method by using the horizontal solar irradiation with the time which was measured in 18 regions across the country for ten years from 2005 to 2014. The method applied to the analysis is to compare the value of the annual total horizontal solar irradiance for one year with the value of that for the previous year of each year, and give +1 when it is higher than the reference ratio, 0 if it is within the reference ratio, and -1 when it is lower than the reference ratio. The characteristics of each region and nationwide characteristics according to the change of each reference ratio were evaluated and analyzed. Through the analysis results, the analysis method applied in this study could be well describe the characteristics of the solar irradiance during some years.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.200.1-200.1
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• 2010

Solar energy is one of the most promising energy resources in the future. For the application and dissemination of solar energy technologies in various fields, reliable data sets of solar irradiation are needed for engineers, researchers, businessmen, and policy makers. Global horizontal solar radiation is needed for the use of flat plate collector, solar domestic hot water system, photovoltaic devices and passive systems like green house. In many countries, solar radiation data accumulated for more then 40 or 50 years and typical weather data are published with average of more then 30 years. In Korea, those global total radiations are measured for about 30 years. With the connections of computer network, measured data could be transmitted to the central control system at key station through Ethernet lines. The data acquisition systems are connected to be automatically controlled by the monitoring network. Global horizontal solar radiation data 16 locations were measured and averaged from 1982 to 2008.

• Journal of Radiation Industry
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• v.6 no.1
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• pp.101-110
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• 2012

This paper is described the review of several selected accelerators and the use of accelerators in various purposes. The electrostatic accelerators and RF accelerators have been developed before the second world war for the purpose of basic research of physics mainly. RF driven accelerators have been achieved higher energy and applied in medical and industrial use after 1980's. Accelerators have improved incorporating new technologies : axial and horizontal injection, stripping extraction, superconducting RF, computer control, superconducting magnet etc.. Also recent key technologies as BT and NT make the expansion of applications of the accelerators.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.1025-1029
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• 2000

This study was conducted to investigate whether a DNA comet assay could be applied for identifying irradiated pork and beef. Pork and beef were irradiated with Co-60 gamma rays at 0.1, 0.3, 0.5, 0.7 and 1.0 kGy, and stored in a freezer Cells separated from the samples were embedded in agarose gel on a slide, dissolved in a lysis solution, and electrophoresed at 2 V/cm for 2.0 min by horizontal electrophoesis. The cells were then stained with a silver staining in order to visualize the DNA using a micro-scope. The DNA fragments of the irradiated cells stretched or migrated out of the cells and formed tails towards the anode, giving the appearance of comets, while unirradiated cells formed very short or no tails. The distance of DNA migration increased with irradiation dose. Since the statistical analysis showed a significant correlation between tail length and irradiation dose, a DNA comet assay could provide not only identification but also estimation of the irradiation dose for irradiated beef and pork.

• Nuclear Engineering and Technology
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• v.7 no.4
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• pp.277-284
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• 1975

A result of measurement for the relative dose distribution of neutron gamma mixed radiation field in the biological irradiation facility installed at TRIGA Mark-III reactor is described. The relative dose distributions of neutron-gamma mixed radiation field in the biological exposure room have been experimentally determined using a thermoluminescent dosimeter. Presented herein in graphical forms are the experimental results obtained. It as observed that the region commonly having the characteristics of rather homogeneous horizontal and lateral dose distributions is confined to the area bounded by the two planes horizontally parallel to the beam direction with heights of about 40 cm and 130 cm, respectively, at distances beyond 100 cm from the segmentary surface of the aluminum pool liner projected into the the exposure room, while other areas show a steeper gradient in dosage, especially the places adjacent to the segment of the aluminum pool liner and near the inner po${\gamma}$lion of the concrete walls of the exposure room.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.7 no.1
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• pp.9-15
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• 1977

The author observed the effect of X-ray irradiation on the secondary palate formation of the rat fetuses. The mothers were exposed to X-radiation on the 10½th, 11½th and 12½th day of gestation with respectively 150, 200, 250, 300 and 350 rads. The fetuses were removed from mothers on 15½h, 16½th and 18½th day of gestation. Morphological changes in palate formation were examined and histochemical preparations were made. 1. In control fetuses, the secondary palates were fully developed on the 15½th to 18½th day of gestation. But in experimental fetuses, many cleft palates were observed in accordance with increase of X-radiation dose. 2. Frequency of incidence of horizontal position of both palated shelves in cleft palate was highest. 3. Accordig to the dislocation of palatal processes, the stain ability of palatal crest was varied. 4. The thickened area of palatal epithelium of palatal crest showed intense methyl green-pyronin and PAS reaction 5. Mesenchymal cell condensation was appeared under the thickened epithelium of palatal process and this mesenchymal tissue showed strong colloidal iron reaction. 6. The stain ability of alizarin red S and alkaline phosphatase reaction of tectal ridge were decreased, in accordance with increase of irradiation doses.

• Journal of the Korean Society of Safety
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• v.23 no.5
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• pp.73-78
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• 2008

The fire hazards and combustion heat of puzzle mats in group day care home were analysed using variable external irradiation level. The fire hazards such as ignition time, ignition temperature, mass loss rate, and flame temperature profile were measured. Incident heat fluxes of $15kW/m^2$, $20kW/m^2$, $25kW/m^2$, $35kW/m^2$, $50kW/m^2$ and $75kW/m^2$ were selected for these experiments. All samples were tested in the horizontal orientation and were wrapped in a single layer of aluminium foil. Each sample was nominally 20mm thick and 100mm square. Five samples of puzzle mat were tested in the study : Type A, B, C, D and E. Type A, B and C are all general grades whereas Type D and E are both Flame retardant grades. As results, Type E of FR-grade showed the best characteristics in safety of the early fire from ignition time, critical heat flux, and ignition and flame temperature data of this study. All specimen of G-grade(Type A, B and C), however, showed the weak in safety of fire.

• Journal of the Korean Solar Energy Society
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• v.32 no.3
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• pp.123-128
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• 2012

Computer simulation of buildings and solar energy systems is being used increasingly in energy assessments and design. The purpose of our work is to predict the surface temperature on inclined surfaces based on ISO-TRY typical weather data. To reach this goal, three studies were performed. They consisted of quantifying the accuracy of various well-known three models. The first type of models calculated diffuse horizontal irradiations from global ones and the second type models computed global irradiations on inclined planes from diffuse and global components on a horizontal surface. The third type of model calculated long-wave radiation and surface temperature from ISO-TRY typical weather data. The proposed model can provide an alternative to building designers in estimating the surface temperature and solar irradiation on inclined surfaces where only the typical meteorological data are available.