• Economic and Environmental Geology
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• v.55 no.1
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• pp.97-109
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• 2022

This study focused on the physicochemical effects of bottom ash dissolved precipitation on the soil and groundwater environment. The iced column and percolation experiments showed that most of the bottom ash particles were drained as the ash-dissolved solution, while the charcoal powder was filtered through the soil. Ion species of Al, As, Cu, Cd, Cr, Pb, Fe, Mn, Ca, K, Si, F, NO₃, SO₄ were analyzed from the eluates collected during the 24 h column test. In the charcoal powder eluates, a high concentration of K was detected at the beginning of the reaction, but it decreased with time. The concentrations of Al and Ca were observed to increase with time, although they existed in trace amount. In the bottom ash eluates, the concentrations of Ca and SO₄ decreased by 30 mg·L^-1 and 67 mg·L^-1, respectively, over 24 h. It is regarded that the infiltration patterns of the bottom ash and biochar in the unsaturated zone were different owing to their particle sizes and solvent properties. It is expected that a significant amount of the bottom ash will mix with the precipitation and percolate below the water table, especially in the case of thin and highly permeable unsaturated zone. The biochar was filtered through the unsaturated zone. The biochar did not dissolve in the groundwater, although it reached the saturation zone. For these reasons, it is considered that the direct contamination by the bottom ash and biochar are unlikely to occur.

• Korean Journal of Agricultural Science
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• v.8 no.2
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• pp.164-170
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• 1981

In order to develop feed source from shrubby area of mountain for dairy cow, some shrub and grass were harvestied by stage of maturity and analyzed the chemical composition of herbage, and fed to milking cow to know the effect on the body weight and milk production. And the results were summarized as follow. 1. The dry matter content of green herbage was ranged average 25~50% and Smilax china and Cocculus thunbergii were the lowerest as 26.25% and 26.36% respectively and Quercus serrata was the highest as 47.19% of the species. 2. The average protein content of herbage was widely ranged from about 5% to 20%. And Pueraria thunbergiana and Albizzia julibrissin were higher as nearly 20% and Miscanthus sinesis and Arundinella hirta were lower as nearly 5~7%. 3. The average crude fiber content of most species was rarged 20~30%. And Corylus heterophylla and Smilax china were lower as about 20% and Miscanthus sinensis and Arundinella hirta were higher as nearly 37%. 4. The crude protein content of most species was decreased and the fiber content was increased by abvanced the stage of maturity. And also moisture content of green herbage was decreased by seasonal changed. 5. When air dry herbage of 5 kg per head/day was substituted for rice straw, the weight of cows and milk yield and solid not fat content were Slightly increased.

• Progress in Medical Physics
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• v.8 no.1
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• pp.25-29
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• 1997

Ir-192 source activity for high dose rate brachytherapy is measured using Farmertype ionization chamber. The source-to-chamber distance is 10 cm and the measured charge unit is converted to activity unit. The measured values are compared to the values provided from vendor. Because of time dependency of Ir-192 source activity, the activities are regularly checked and compared to calculated values. As the accuracy of Ir-192 source activity is depend on the mechanical measurement setup, we estimated the precision of remote controlled source dwell position using home-made device and film scanner. The difference between measured and predicted dwell position is within 1 mm. As a result, the errors of source activity are 0.7${\pm}$1.5 ％ for measured and vendor-provided values and 0.l${\pm}$1.2％ for measured and time-dependent calculated vlaues. In conclusion, our measured activity has been comparable to the values provided from vendor and our brachytherapy unit has been very accurate until now. Regular quality control of brachytherapy is essential for successful treatment which depends on the accuracy of source position and activity.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.4
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• pp.373-378
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• 1999

This study was conducted to investigate the effects of application of the dolomite particles and the shell powder on soil characteristics, dry matter yield and nutritive value of forage in sandy loam soil at the Experimental Field of National Livestock Research Institute, Suweon, from 1994 to 1996. This was compared with control, lime, dolomite 0.5mm, 2.0mm, 4.0mm, and shell powder in mixed pasture. Although there was no significant difference, average dry matter yield for 3 years was increased with the application of lime, dolomite 2.0mm, 0.5mm, control, 4.0mm and shell powder in order. Average crude protein yield of forages was increased with the application of dolomite 2.0mm, 0.5mm, control, lime, shell powder and 4.0mm in order. Lime requirement was slightly increased from 2,410 to 4,853kg per ha with the lapse of time. Although soil hardness was optimum level by second year, it was apt to become hard little by little. Solid phase of soil was lowered with dolomite 0.5mm treatment. The results demonstrated that dolomite and shell powder could be settled a dust problem in farms and a coast pollution as lime substitutes for soil improvement. Therefore, it is desirable for dry matter yield and crude protein yield to applicate the dolomite 2.0mm every 3 years and the shell powder more frequently in sandy loam soil.

• Journal of KIISE:Software and Applications
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• v.36 no.10
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• pp.777-785
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• 2009

Collaborative filtering is a technique used to predict whether a particular user will like a particular item. User-based or item-based collaborative techniques have been used extensively in many commercial recommender systems. In this paper, a hybrid collaborative filtering method that combines user-based and item-based methods using a low-dimensional linear model is proposed. The proposed method solves the problems of sparsity and a large database by using NMF among the low-dimensional linear models. In collaborative filtering systems the methods using the NMF are useful in expressing users as semantic relations. However, they are model-based methods and the process of computation is complex, so they can not recommend items dynamically. In order to complement the shortcomings, the proposed method clusters users into groups by using NMF and selects features of groups by using TF-IDF. Mutual information is then used to compute similarities between items. The proposed method clusters users into groups and extracts features of groups on offline and determines the most suitable group for an active user using the features of groups on online. Finally, the proposed method reduces the time required to classify an active user into a group and outperforms previous methods by combining user-based and item-based collaborative filtering methods.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.4
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• pp.121-131
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• 2006

This study was designed to determinate the effects of dried leftover food and green tea by-product on laying hens performance and egg quality in hens. A total of 210 "Tetran Brown" layers 50-weeks of age were assigned to 7 treatments in a completely randomized design. Each treatment had five replicates per treatment with six layers per replication. Seven dietary treatments were a control diet (formula diet) and dried leftover food (DLF) mixed in 10, 20, 30 and 40% to the control diet substituting the corn grain and soybean meal, control diet containing 1.0% GTB without DLF supplementation and control diet containing 30% DLF plus 1.0% GTB supplementation. The trial period was for 8 weeks. The egg production rate of layers was significantly increased in 10, 20 and 40% DLF treatments compared to that of the control treatment (P<0.05). The egg weight was significantly decreased in 10% DLF treatment compared to that of the control (P<0.05). The feed intake of layers was higher in 20% DLF and 30% DLF plus 1.0% GTB treatment than that of the control (P<0.05). The feed conversion ratio significantly decreased in 10% DLF and control plus 1.0% GTB treatments compared to that of the control (P<0.05). The egg yolk cholesterol not varied among the DLF and control treatments (P>0.05). However, the linolenic acid content of egg yolk was significantly increased in DLF and control treatments both containing 1.0% GTB supplementation.

• Journal of Life Science
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• v.22 no.3
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• pp.324-331
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• 2012

Bacteriological examination of spring water in Jeju City was conducted. A total of 21 spring water samples were collected from January to April, 2010. During the study period, the range of temperature was 0.6 to $15.4^{\circ}C$, and the results of the analyses showed that hydrogen ion concentrations (pH) for spring water were 0.43 to 7.9. Salinity levels for the samples averaged from 3.0 to 1.64%, and levels of water-dissolved oxygen were 1.85 to 6.06 mg/l. The range of total coliforms in spring water samples at 21 stations located in the designated spring water were <1.8->1,600 MPN/100 ml. Furthermore, the range of geometric means of total coliforms was 9.9-151.6 MPN/100 ml, while the range of fecal coliforms in spring water samples at 21 stations located in the designated spring water area was <1.8->1,600 MPN/100 ml. Finally, the range of geometric mean of fecal coliforms was 3.1-151.6 MPN/100 ml. The level of microbial contamination was examined in 21 samples for indications of bacterial contamination such as heterotrophic bacteria, Escherichia coli O157:H7, Salmonella spp., Vibrio parahaemolyticus, Staphylococcus aureus, and Shigella spp. were frequently detected in the spring water. Salmonella spp., Shigella spp., Vibrio parahaemolyticus, and S. aureus were detected in the range of $0-0.5{\times}10^1$, $0-0.1{\times}10^1$, $0-0.1{\times}10^1$, and $0-0.3{\times}10^1$ CFU/ml, respectively, while E. coli O157:H7 was not detected in the examined spring water samples.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.59-59
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• 2019

벼룩이울타리(Arenaria juncea M.Bieb.)는 7~8월에 백색의 꽃이 취산화서로 아름답게 피며, 산지, 산비탈 또는 메마른 초지에 자생한다. 청열 및 양혈의 효능이 있고, 은시호의 대용으로 쓰이며, 뿌리에는 triterpenoid saponins과 sapogenin이 함유되어 있다. 본 연구는 분화용 식물로 벼룩이울타리를 활용하기 위한 효율적인 포트 정식방법을 개발하기 위하여 수행되었다. 실험은 2018년 선행연구에서 생산된 유묘를 7월 2일에 정식하여 10월 15일까지 약 15주 동안 재배하였다. 대조구는 플라스틱 화분 10호($9{\times}9cm$)에 원예상토를 충진하고 200구 트레이에 셀 당 4립씩 파종하여 생산된 1셀을 정식하였다. 재배 실험은 용기종류[비닐포트(3, 4치), 플라스틱 포트(8, 10, 12호)], 토양 종류[원예상토, 중화 피트모스:펄라이트(3:1, 4:1), 마사토:중화 피트모스(2:1, 3:1)], 묘의 소질[파종 립수(1, 2, 4, 6립), 파종 용기(162, 200, 288구 트레이)] 등을 달리하여 진행하였다. 연구의 결과, 벼룩이울타리는 토양의 양이 많을수록 생육이 양호한 결과를 보여, 플라스틱 12호에 재배하는 것이 분화용으로 가장 효과적이었다. 한편, 비닐 4치와 플라스틱 10호의 경우, 플라스틱 12호와 생육에 큰 차이가 없어 경제적인 것으로 판단된다. 벼룩이울타리는 원예상토에서 재배하는 것이 전반적으로 생육이 우수하였으며, 다음으로 마사토와 피트모스 혼용토 순이었다. 그러나 피트모스와 펄라이트 혼용토는 비율과 관계없이 생육이 감소하며, 잎에 황백화 현상이 나타났다. 셀당 파종량을 달리하여 육묘한 후 정식한 결과, 전반적인 생육은 1립 파종묘에서 양호하였으나, 2, 4, 6립 파종묘가 1립 처리구에 비해 포트당 엽수가 약 1.35, 1.44, 2.01배 증가하는 경향을 보였다. 그러므로 유묘 생산시 셀당 파종량을 늘려 재배하는 것이 분화용으로 효과적일 것으로 판단된다. 파종용기별 유묘의 생육은 162, 200, 288구 트레이 순이었으나, 정식 후 약 15주 동안 재배한 결과, 162, 200구에서 생산된 유묘를 정식하는 것이 288구보다 양호하였다. 따라서, 육묘 단계에서 토양 및 공간을 절약할 수 있는 200구에 파종하여 재배하는 것이 효율적인 방법으로 생각된다. 결론적으로, 벼룩이울타리의 분화용 재배는 플라스틱포트 12호에 원예상토를 충진하고 200구 트레이에 4립 또는 6립을 파종하여 육묘한 묘를 정식하는 것이 가장 효과적이다. 한편, 경제적인 측면을 고려할 때, 재배면적을 적게 차지하는 비닐포트 4치 또는 플라스틱 포트 10호에 마사토와 중화 피트모스를 혼용하여 충진한 다음 유묘를 이식하는 것도 하나의 방법으로 판단된다.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.5
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• pp.160-168
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• 2012

This study generated regression models to estimate the carbon storage and uptake from the urban deciduous landscape trees through a direct harvesting method, and established essential information to quantify carbon reduction from urban greenspace. Tree species for the study included Acer palmatum, Zelkova serrata, Prunus yedoensis, and Ginkgo biloba, which are usually planted as urban landscape trees. Tree individuals for each species were sampled reflecting various diameter sizes at a given interval. The study measured biomass for each part including the roots of sample trees to compute the total carbon storage per tree. Annual carbon uptake per tree was quantified by analyzing radial growth rates of stem samples at breast height. The study then derived a regression model easily applicable in estimating carbon storage and uptake per tree for the 4 species by using diameter at breast height(dbh) as an independent variable. All the regression models showed high fitness with $r^2$ values of 0.94~0.99. Carbon storage and uptake per tree and their differences between diameter classes increased as the diameter sizes got larger. The carbon storage and uptake tended to be greatest with Zelkova serrata in the same diameter sizes, followed by Prunus yedoensis and Ginkgo biloba in order. A Zelkova serrata tree with 15cm in dbh stored about 54kg of carbon and annually sequestered 7 kg, based on a regression model for the species. The study has broken new grounds to overcome limitations of the past studies which substituted, due to a difficulty in direct cutting and root digging of urban landscape trees, coefficients from the forest trees such as biomass expansion factors, ratios of below ground/above ground biomass, and diameter growth rates. Study results can be useful as a tool or skill to evaluate carbon reduction by landscape trees in urban greenspace projects of the government.

• Journal of Food Hygiene and Safety
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• v.24 no.1
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• pp.69-77
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• 2009

This study was performed to investigate the effect of dried powder of chestnut on lipid metabolism, anti-thrombotic effect in rats. Thirty 5-week-old male Sprague Dawley (SD) rats were randomly allocated into five groups and used for experiment. We examined the lipid metabolism and antithrombotic capacity of SD rats administered for 5 weeks with 0.16 g/kg, 0.5 g/kg chestnut flesh powder and 0.16 g/kg, 0.5 g/kg chestnut inner shell and flesh powder mixture, respectively. Food intake, body weight gain and food efficiency ratio were also checked. The levels of serum triglyceride and tree fatty acid were not statistically significant between the all experimental groups. However, the antithrombotic capacity and total lipid levels of the treatment groups were significantly lower than those of the negative control group. These results suggest that the supplementation of chestnut on diet lower the total lipid level in SD rats.