• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.29-45
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• 2017

This study explored spatiotemporal variability of water quality in correspondence with hydro-meteorological factors in the four stations of Euiam Reservoir located in the upstream region of the North-Han River from May 2012 to December 2015. Seasonal effect was apparent in the variation of water temperature, DO, electric conductivity and TSS during the study period. Stratification in the water column was observed in the near dam site every year and vanished between August and October. Increase of nitrogen nutrients was observed when inflowing discharge was low, while phosphorus increase was distinct both during the early season with increase of inflowing discharge and the period of severe draught persistent. Duration persisting high concentration of Chl-a (>$25mg\;m^{-3}$: the eutrophic status criterion, OECD, 1982) was 1~2 months of the whole year in 2014~2015, while it was almost 4 months in 2013. Water quality of Euiam Reservoir appeared to be affected basically by geomorphology and source of pollutants, such as longitudinally linked instream islands and Aggregate Island, inflowing urban stream, and wastewater treatment plant discharge. While inflowing discharge from the dams upstream and outflow pattern causing water level change seem to largely govern the variability of water quality in this particular system. In the process of spatiotemporal water quality change, factors related to climate (e.g. flood, typhoon, abruptly high rainfall, scorching heat of summer), hydrology (amount of flow and water level) might be attributed to water pulse, dilution, backflow, uptake, and sedimentation. This study showed that change of water quality in Euiam Reservoir was very dynamic and suggested that its effect could be delivered to downstream (Cheongpyeong and Paldang Reservoirs) through year-round discharge for hydropower generation.

• Fire Science and Engineering
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• v.31 no.4
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• pp.95-102
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• 2017

The fires in the traditional markets often occur recently with the most of them expanded into great fires so that the damage is very serious. The status of traditional markets handling the distribution for ordinary people is greatly shrunk with the aggressive marketing of the local large companies and the foreign large distribution companies after the overall opening of the local distribution market. Most of the traditional markets have the history and tradition from decades to centuries and have grown steadily with the joys and sorrows of ordinary people and the development of the local economy. The fire developing to the large fire has the characteristics of the problem that the fire possibility is high since all products can be flammable due to the deterioration of facilities, the arbitrary modification of equipment, and the crowding of the goods for sale. Furthermore, most of the stores are petty with their small sizes so that the passage is narrow affecting the passage of pedestrians. Accordingly, the traditional markets are vulnerable to fire due to the initial unplanned structural problem so that the large scale fire damage occurs. The study is concerned with systematically classifying and analyzing the result by applying the TRIZ tool to the fire risk factors to extract the fundamental problem with the fire of the traditional market and make the active response. The study was done for preventing the fire on the basis of it and the expansion to the large fire in case of fire to prepare the specific measure to minimize the fire damage. On the basis of the fire expansion risk factor of the derived traditional market, the study presented the passive measures such as the improvement of the fire resisting capacity, the fire safety island, etc. and the active and institutional measures such as the obligation of the fire breaking news facilities, the application of the extra-high pressure pump system, the divided use of the electric line, etc.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.3
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• pp.83-91
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• 2019

The purpose of this study is to assess a fire-damaged concrete structure using a digital camera and image processing software. To simulate it, mortar and paste samples of W/C=0.5(general strength) and 0.3(high strength) were put into an electric furnace and simulated from $100^{\circ}C$ to $1000^{\circ}C$. Here, the paste was processed into a powder to measure CIELAB chromaticity, and the samples were taken with a digital camera. The RGB chromaticity was measured by color intensity analyzer software. As a result, the residual compressive strength of W/C=0.5 and 0.3 was 87.2 % and 86.7 % at the heating temperature of $400^{\circ}C$. However there was a sudden decrease in strength at the temperature above $500^{\circ}C$, while the residual compressive strength of W/C=0.5 and 0.3 was 55.2 % and 51.9 % of residual strength. At the temperature $700^{\circ}C$ or higher, W/C=0.5 and W/C=0.3 show 26.3% and 27.8% of residual strength, so that the durability of the structure could not be secured. The results of $L^*a^*b$ color analysis show that $b^*$ increases rapidly after $700^{\circ}C$. It is analyzed that the intensity of yellow becomes strong after $700^{\circ}C$. Further, the RGB analysis found that the histogram kurtosis and frequency of Red and Green increases after $700^{\circ}C$. It is analyzed that number of Red and Green pixels are increased. Therefore, it is deemed possible to estimate the degree of damage by checking the change in yellow($b^*$ or R+G) when analyzing the chromaticity of the fire-damaged concrete structures.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.4
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• pp.83-89
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• 2020

For the past few decades, as part of efforts to protect the environment where fossil fuels, which have been a key energy resource for mankind, are becoming increasingly depleted and pollution due to industrial development, ecofriendly secondary batteries, hydrogen generating energy devices, energy storage systems, and many other new energy technologies are being developed. Among them, the lithium-ion battery (LIB) is considered to be a next-generation energy device suitable for application as a large-capacity battery and capable of industrial application due to its high energy density and long lifespan. However, considering the growing battery market such as eco-friendly electric vehicles and drones, it is expected that a large amount of battery waste will spill out from some point due to the end of life. In order to prepare for this situation, development of a process for recovering lithium and various valuable metals from waste batteries is required, and at the same time, a plan to recycle them is socially required. In this study, we introduce a nanoscale pattern transfer printing (NTP) process of Li2CO3, a representative anode material for lithium ion batteries, one of the strategic materials for recycling waste batteries. First, Li2CO3 powder was formed by pressing in a vacuum, and a 3-inch sputter target for very pure Li2CO3 thin film deposition was successfully produced through high-temperature sintering. The target was mounted on a sputtering device, and a well-ordered Li2CO3 line pattern with a width of 250 nm was successfully obtained on the Si substrate using the NTP process. In addition, based on the nTP method, the periodic Li2CO3 line patterns were formed on the surfaces of metal, glass, flexible polymer substrates, and even curved goggles. These results are expected to be applied to the thin films of various functional materials used in battery devices in the future, and is also expected to be particularly helpful in improving the performance of lithium-ion battery devices on various substrates.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.1
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• pp.77-81
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• 2009

Purpose: The PET of the PET/CT (Positron Emission Tomography/Computed Tomography) quantitatively shows the biological and chemical information of the body, but has limitation of presenting the clear anatomic structure. Thus combining the PET with CT, it is not only possible to offer the higher resolution but also effectively shorten the scanning time and reduce the noises by using CT data in attenuation correction. And because, at the CT scanning, the contrast media makes it easy to determine a exact range of the lesion and distinguish the normal organs, there is a certain increase in the use of it. However, in the case of using the contrast media, it affects semi-quantitative measures of the PET/CT images. In this study, therefore, we will be to establish the reliability of the SUV (Standardized Uptake Value) with CT data correction so that it can help more accurate diagnosis. Materials and Methods: In this experiment, a total of 30 people are targeted - age range: from 27 to 72, average age : 49.6 - and DSTe (General Electric Healthcare, Milwaukee, MI, USA) is used for equipment. $^{18}F$- FDG 370~555 MBq is injected into the subjects depending on their weight and, after about 60 minutes of their stable position, a whole-body scan is taken. The CT scan is set to 140 kV and 210 mA, and the injected amount of the contrast media is 2 cc per 1 kg of the patients' weight. With the raw data from the scan, we obtain a image showing the effect of the contrast media through the attenuation correction by both of the corrected and uncorrected CT data. Then we mark out ROI (Region of Interest) in each area to measure SUV and analyze the difference. Results: According to the analysis, the SUV is decreased in the liver and heart which have more bloodstream than the others, because of the contrast media correction. On the other hand, there is no difference in the lungs. Conclusions: Whereas the CT scan images with the contrast media from the PET/CT increase the contrast of the targeted region for the test so that it can improve efficiency of diagnosis, there occurred an increase of SUV, a semi-quantitative analytical method. In this research, we measure the variation of SUV through the correction of the influence of contrast media and compare the differences. As we revise the SUV which is increasing in the image with attenuation correction by using contrast media, we can expect anatomical images of high-resolution. Furthermore, it is considered that through this trusted semi-quantitative method, it will definitely enhance the diagnostic value.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.5
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• pp.353-360
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• 1984

As an effort to expand the utilization of mackerel which has been thought disadvantageous to processors due to the defects in bloody dark color of meat, high content of lipid, and low stability of protein, and to develope a new type of product, so called, preservative fish meat paste, the processing method was studied in which dielectric heating was applied by means of cooking, pasteurization, dehydration, and control of water activity. The principle of this method is based on that dielectric heating can initiate a rapid dispersion or displacement of moisture in the meat tissue so that the level of water acivity can be controlled by dehydration with hot air meanwhile the product is cooked, pasteurized, and texturized. And the product is finally heated with electric heaters and vacuum sealed to stabilize water activity and storage stability. In present paper, a formula for preparing the fish meat-stach paste, the conditions of dielectric heating and dehydration, shape and size of the product, and other parameters were tested to optimize the process operation. A formula of the fish meat-starch paste to provide proper textural properties and water activity was $10\%$ starch, $1.5\%$ salt, $3\%$ soybean, $0.6\%$ MSG, $2\%$ sucrose, and $3\%$ sorbitol against the weight of fish meat. A proper shape and size of the product to avoid foaming and case hardening during heating was sliced disc of 8 cm $diameter{\times}0.8$ cm thickness or $10{\times}10$ cm square plate with 1.0 cm thickness. The disc shape was recommended because it resulted more uniform heating, minimum foaming and case hardening. And it was also advantageous that disc was simply provided when the fish meat disc was stuffed in the same, solidified in boiling water for 2 to 3 minutes, and sliced. Condition of dielectric heating was critical to decide the levels of sterility, water activity, and textural property of the product. The temperature at the center of the meat disc slices was raised up to $95^{\circ}C$ in 1.5 minutes so that continuous exposure to microwave caused expanded tissue and hardening ending up with a higher water content. Heating for 5 to 6 minutes was adequate to yield the final water activity of 0.86 to 0.83(35 to $40\%$ moisture). It is important, however, that heating had to be done periodically, for instance, in the manner of 2.0, 1.5, 1.5, and 1.0 minute to give enough time to displace or evaporate moisture from the meat tissue. The product was dehydrated for 2 to 3 minutes by hot air of $60^{\circ}C$, 3 to 5m/sec and finally exposed to electric heaters for 5 to 6 minutes until the surface was roasted deep brown. These conditions of heating and dehydration resulted in a complete reduction of total plate count from an initial count of $5.3{\times}10^6/g$ to less than $3{\times}10^2/g$. General composition of the product was $40.1\%$ moisture, $20.8\%$ protein, $17.4\%$ lipid, $16.2\%$ carbohydrate, and $5.5\%$ ash. Textural properties revealed folding test AA, hardness 42, cohesiveness 0.53, toughness 4.6, and elasticity 0.8.

• Journal of Forest and Environmental Science
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• v.21 no.1
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• pp.34-58
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• 2005

This study was executed to find out how to improve the planting and use of landscaping plants in Weonju and Hoengseong. 1. The number of street trees were 22,068 and the species number were 10 species in Weonju in 2004. The major species of street trees were Ginkgo biloba(58%), Prunus sargentii(15%), Zelkova serrata(9%), Prunus armeniaca var. ansu(8%), and Acer palmatum(6%). The ratio of native species versus exotic were 50:50. In Hoengseong, the number of street trees was 13,500 and the species number were 15 species. The major species of street trees were Prunus sargentii(42%), Ginkgo biloba(23%), Acer triflorum(12%), Prunus armeniaca var. ansu(6%), and Prunus mume(4%). The ratio of native species versus exotic were 67:33. The species of which planting frequency within two areas was very high were Ginkgo biloba and Prunus sargentii. 2. It is necessary to select tree species suitable for the characteristics of the locality and to raise distinctive street trees that contribute to the tourist industry. For the purpose, the appropriate street trees in two areas are Cornus controversa, Quercus aliena, Zelkova serrata, Prunus padus, Sorbus alnifolia, Sorbus comixta, Albizzia julibrissin, Acer triflorum, Styrax japonica, Chionanthus retusus, Celtis sinensis, Prunus yedoensis, Malus sieboldii, Crataegus Pinnatifida, Prunus armeniaca var. ansu and Pyrus pyrifolia etc.. 3. Appropriate pruning adds to the aesthetic and prolongs the useful life, it also requires less managing of insects and diseases to maintain good healthy of street trees. Street trees were not properly pruned due to electric lines and shortage of pruning information. The pruning was controlled by Korea Electric Power Co, which has no pruning information. Pruning must be maintained by a professional landscape company to maintain good shape such as with Bonsai. The shrubs planting zone between street trees and other trees, and preservation plates were established for healthy of street trees. They have to be repaired and maintained well to keep better environmental conditions. The proper fertilization, the control of pests and diseases, the installation of drainpipe and the use of soil brought from another place were needed to improve the planting, use and maintenance of landscape plants. 4. The species number of school trees and flowers of 102 schools in Weonju and Hoengseong were 17species, 16species respectively. The major species of school trees in Weonju were Juniperus chinensis(24%), Ginkgo biloba(17%), Pinus densiflora(14%), Zelkova serrata(14%), and Pinus koraiensis(9%), and those of school trees in Hoengseong were Pinus koraiensis(44%), Abies holophylla(25%), Juniperus chinensis(8%), and Ginkgo biloba(8%). The major species of school flowers in Weonju were Rosa centifolia(47%), Forsythia koreana(24%), Magnolia kobus(12%), and Rhododendron schlippenbachii(6%), and those of school flowers in Hoengseong were Forsythia koreana(36%), Rhododendron schlippenbachii(33%), Magnolia kobus(6%) and Dicentra spectabilis(6%). 5. The species number of the protection trees designated by Woenju and Hoengseong were 15 species. The major species of protection trees were Zelkova serrata(100 trees), Ginkgo biloba(18) Pinus densiflora(7), Quercus spp. (5), Juniperus chinensis(4) and Alnus japonica(4). 6. The landscape plants planted around 2004 in weonju were Prunus yedoensis(2,563 trees), Betula platyphylla var. japonica(2,000), Abies holophylla(1,785), Diospyros kaki(1,100), Prunus sargentii(880) and Prunus armeniaca var. ansu(708) etc.. The shrubs planted were Rhododendron obutusum(21,559 plants), Rosa centifolia (7,150), Rhododendron yedoense var. poukhanense(5,950), Forsythia koreana(3,000) and Ligustrum obtusi[olium(2,500) etc.. The landscape plants planted in Hoengseong Acer triflorum(928trees), Prunus yedoensis(455), Zelkova serrata(327), Thuja orientalis(261), Prunus sargentii(257), Pinus koraiensis(200), Prunus persica for. rubro-plena(200) and Pyrus pyrifolia (200) etc.. The shrubs planted were Rhododendron yedoense var. poukhanense(15,936), Syringa dilatata(10,090), Forsythia koreana(9,660), Cercis chinensis(3,200), Buxus microphylla var. koreana(2,600) and Rosa centifolia(1,868) etc.. 7. The species numbers of the herbaceous plants planted in 2004 in Weonju were 24 species and the ratio of native species versus exotic were 7:17. The major species of perennial plants were Aster koraiensis(30,656 plants), Coreopsis drummondii(7,656), Rudbeckia bicolor(6,000), Chrysanthemum morifolium(4,850) and Chrysanthemum zawadskii var. latilobum(4,312). The major species of annuals and biennials were Cosmos bipinnatus(672,000 plants), Zinnia elegans(35,600), Petunia hybrida(26,920), Viola tricolor(23,000), Helianthus annuus(17,000), and Geranium cinereum var. pubcaulescens(5,200). In Hoengseong, the numbers of herbaceous plants were 906,310 plants and the species numbers were 15 species. The major species of perennials plants were Aster koraiensis(70,480 plants), Hemerocallis fulva(20,070), and Phlox drummondii(18,000). The major species of annuals and biennials were Phlox hybrida(174,000 plants), Cosmos bipinnatus(125,000), Zinnia elegans(109,000), Tagetes patula(96,700), Vinca rosea(89,000) and Calendula officinalis(70,000). 8. Through these result, it was thought that the diversification of planting species, the selection of plants suitable to each space and the generalization of use of native species were needed.

• Economic and Environmental Geology
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• v.39 no.4 s.179
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• pp.369-384
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• 2006

Korean Peninsula, located on the southeastern part of Eurasian plate, belongs to the intraplate region. The characteristics of intraplate earthquake show the low and rare seismicity and the sparse and irregular distribution of epicenters comparing to interplate earthquake. To evaluate the exact seismic activity in intraplate region, long-term seismic data including historical earthquake data should be archived. Fortunately the long-term historical earthquake records about 2,000 years are available in Korea Peninsula. By the analysis of this historical and instrumental earthquake data, seismic activity was very high in 16-18 centuries and is more active at the Yellow sea area than East sea area. Comparing to the high seismic activity of the north-eastern China in 16-18 centuries, it is inferred that seismic activity in two regions shows close relationship. Also general trend of epicenter distribution shows the SE-NW direction. In Korea Peninsula, the first seismic station was installed at Incheon in 1905 and 5 additional seismic stations were installed till 1943. There was no seismic station from 1945 to 1962, but a World Wide Standardized Seismograph was installed at Seoul in 1963. In 1990, Korean Meteorological Adminstration(KMA) had established centralized modem seismic network in real-time, consisted of 12 stations. After that time, many institutes tried to expand their own seismic networks in Korea Peninsula. Now KMA operates 35 velocity-type seismic stations and 75 accelerometers and Korea Institute of Geoscience and Mineral Resources operates 32 and 16 stations, respectively. Korea Institute of Nuclear Safety and Korea Electric Power Research Institute operate 4 and 13 stations, consisted of velocity-type and accelerometer. In and around the Korean Peninsula, 27 intraplate earthquake mechanisms since 1936 were analyzed to understand the regional stress orientation and tectonics. These earthquakes are largest ones in this century and may represent the characteristics of earthquake in this region. Focal mechanism of these earthquakes show predominant strike-slip faulting with small amount of thrust components. The average P-axis is almost horizontal ENE-WSW. In north-eastern China, strike-slip faulting is dominant and nearly horizontal average P-axis in ENE-WSW is very similar with the Korean Peninsula. On the other hand, in the eastern part of East Sea, thrust faulting is dominant and average P-axis is horizontal with ESE-WNW. This indicate that not only the subducting Pacific Plate in east but also the indenting Indian Plate controls earthquake mechanism in the far east of the Eurasian Plate. Crustal velocity model is very important to determine the hypocenters of the local earthquakes. But the crust model in and around Korean Peninsula is not clear till now, because the sufficient seismic data could not accumulated. To solve this problem, reflection and refraction seismic survey and seismic wave analysis method were simultaneously applied to two long cross-section traversing the southern Korean Peninsula since 2002. This survey should be continuously conducted.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.413-419
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• 2008

The susceptibility of five stink bugs species collected soybean fields in Milyang in 2006 to seven insecticides was evaluated using electric auto-sprayer. The insecticide deltamethirn had the lowest median lethal concentration ($LC_{50}$) of 0.4 to 2.3 ppm regardless of stink bugs species while phenthoate had the highest concentration for one-banded stink bug (Piezodorus hybneri), green stink bug (Nezara antennata), sloe bug (Dolycoris baccarum), and brown marmorated stink bug, (Halyomorpha halys); and fenthion for bean bug (Riptortus clavatus). The average $LC_{50}$ for stink bugs to seven insecticides was lowest at 7.5 ppm for R. clavatus, followed by 16.6 ppm for H. halys, 17.6 ppm for D. baccarum, 19.1 ppm for N. antennata, and 28.4 ppm for P. hybneri. The relative tolerance ratio (TR), which is the TR of 90 percent lethal concentration ($LC_{90}$) of stink bugs to the recommended concentration, was the lowest in fipronil for R. clavatus, P. hybneri and D. baccarum; fenitrothion for N. antennata; and fenthion for H. halys. The relative average TR was lowest at 0.09 for R. clavatus, followed by 0.26 for D. baccarum, 0.30 for N. antennata, 0.37 for P. hybneri, and 0.39 for H. halys. Therefore, insecticides susceptibility was highest for R. clavatus and lowest for P. hybneri while the relative average TR was lowest for R. clavatus and highest for H. halys. Accordingly, it is expected that stink bugs can be effectively controlled with by spraying insecticides in soybean field because the relative average TR value of stink bugs was below 1.0, indicating high susceptibility of stink bugs to insecticides.

• Journal of Bio-Environment Control
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• v.27 no.2
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• pp.166-172
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• 2018

This study set out to conduct a field survey with smart greenhouse-based farms in seven types to figure out the actual state of smart greenhouses distributed across the nation before selecting a system to implement an optimal greenhouse environment and doing a research on higher productivity based on data related to crop growth, development, and environment. The findings show that the farms were close to an intelligent or advanced smart farm, given the main purposes of leading cases across the smart farm types found in the field. As for the age of farmers, those who were in their forties and sixties accounted for the biggest percentage, but those who were in their fifties or younger ran 21 farms that accounted for approximately 70.0%. The biggest number of farmers had a cultivation career of ten years or less. As for the greenhouse type, the 1-2W type accounted for 50.0%, and the multispan type accounted for 80.0% at 24 farms. As for crops they cultivated, only three farms cultivated flowers with the remaining farms growing only fruit vegetables, of which the tomato and paprika accounted for approximately 63.6%. As for control systems, approximately 77.4% (24 farms) used a domestic control system. As for the control method of a control system, three farms regulated temperature and humidity only with a control panel with the remaining farms adopting a digital control method to combine a panel with a computer. There were total nine environmental factors to measure and control including temperature. While all the surveyed farms measured temperature, the number of farms installing a ventilation or air flow fan or measuring the concentration of carbon dioxide was relatively small. As for a heating system, 46.7% of the farms used an electric boiler. In addition, hot water boilers, heat pumps, and lamp oil boilers were used. As for investment into a control system, there was a difference in the investment scale among the farms from 10 million won to 100 million won. As for difficulties with greenhouse management, the farmers complained about difficulties with using a smart phone and digital control system due to their old age and the utter absence of education and materials about smart greenhouse management. Those difficulties were followed by high fees paid to a consultant and system malfunction in the order.