• Journal of Life Science
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• v.20 no.9
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• pp.1353-1357
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• 2010

Quantification of the ecosystem respiration is essential in understanding the carbon cycling of natural and disturbed landscapes. Soil respiration and some environmental factors which affect soil respiration were investigated in a Larix leptolepis plantation inKongju, Korea. Soil respiration was measured at midday of the $15^{th}$ and $30^{th}$ day of every month from May to December in a non-cutting area (Control) and a cutting area (Treatment) with IRGA Soil Respiration Analyzer. Throughout the study period, average soil temperature and water content were $23.3{\pm}0.5^{\circ}C$ and $27.76{\pm}7.12%$ for control, and $25.9{\pm}3.1^{\circ}C$ and $24.55{\pm}5.12%$ for treatment, respectively. There was a positive correlation ($R^2$=0.8905) between soil respiration and soil temperature in the study area. However, there was no significant correlation between soil respiration and soil moisture ($R^2$=0.4437). The seasonal soil respiration increased in the summer and decreased in the winter. In August, maximum soil respirations in the control and treatment areas were $0.82{\pm}0.13$ and $1.32{\pm}0.10$ $gCO_2{\cdot}^{-2}{\cdot}r^{-1}$, respectively. Total amounts of $CO_2$ evolution in the control and treatment areas from May to December in 2008 were 2,419.2 and 3,610.8 $CO_2g{\cdot}m^{-2}$, respectively. The amount of soil respiration in the treatment area was 49.3% greater than in the control. Increased soil respiration in the treatment area may be due to increased soil temperature, which drives increased microbial decomposition. According to our present investigation, forest cutting will increase the atmospheric $CO_2$ by increasing soil respiration.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.6
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• pp.671-683
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• 1995

This study was aimed to provide understanding on the eco-physiological response of barley tillers as affected by sowing depth. Yield and yield contribution rate of tillers were investigated with the data of field experiments in the former Wheat and Barley Research Institute of Suwon, Korea from October 1983 to July 1984. When barley was sowed in various depth of 1, 3, 5, 7 and 9cm below the ground surface, 13 mainstem leaves appeared by 3 and 5cm treatments, and 11 leaves by 1, 7 and 9cm treatments. The effective tillers were observed from 8/0 in lcm depth, while 10/0 in 3-5cm depth and 9/0 in 7cm depth. There was no coleoptile tiller in 7cm depth sowing. Deep and shallow sowings produced fewer leaves and tillers, as early growth was hindered by deep sowing whereas cold damage was apparent in shallow sowing. Accordingly, more effective tillers per plant and higher grain weight per ear were observed in 3∼5cm depth sowing. Yield contribution by the tillers with various sowing depth was as follows: mainstem, 1, 2, 11, 3, 21, 4 and 12. The contribution of 1P, 13, 2P, 23 and 31 varied with the treatments.

• Journal of Animal Science and Technology
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• v.46 no.5
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• pp.821-832
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• 2004

A total of 80 pigs were used to investigate the effect of dietary glycine betaine(N,N,N-trimethylglycine) on pork quality during cold storage. About 70 kg pigs were randomly a1loted into one of four experimental diet groups(0%, 0.2%, 0.4% and 0.6% glycine betaine). Pigs were slaughtered at approximately 110 kg live weight, and pH, color(CIE $L^* a^* b^*$), shear force, sarcomere length, lipid oxidation and composition of fatty acid were measured in pork loin for 13 days of cold storage. The concentration of glycine betaine in pork loin was significantly increased(P<0.05) with increasing of glycine betaine level in diet. Pork loins from dietary betaine groups showed significantly higher muscle pH and lower CIE $b^*$ values compared to control group after 13 days of storage. There were significant differences in shear force values among pork loins from diet groups at 24 hrs postmortem. However, pork loins from control diet showed longer sarcomere length than those of dietary betaine groups. Dietary glycine betaine increased the ratio of saturated fatty acids and decreased unsaturated fatty acids in pork loins. Especially the ratios of linoleic and myristic acid were decreased with increasing dietary betaine level. However, dietary glycine betaine did not affect lipid oxidation (TSARS) and sensory evaluation during cold storage.

• Korean Journal of Poultry Science
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• v.16 no.3
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• pp.149-156
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• 1989

Two broiler experiments were carried out to determine whether supplementation of zeolite in the diet would affect broiler performance and economical efficiency. Day old male broiler chickens of Abor Acres strain were used. In the first experiment,60 birds were distributed into f groups of 10 birds each. Three groups of chickens were randomly placed on one of the following single-stage (0-6wks) experimental diets； control diet (non-supplemented) or 2% zeolite supplemented diet (supplemented to the control). In the second experiment,216 birds were distributed into 24 groups of 9 birds each. Eight groups of chickens were randomly placed on one of the 3 two-stage diet (starter；0-4wks, finisher；5-7wks)；control diet ($T_1$ , non-supplemented), 2% zeolite diet ($T_2$：isocaloric and isonitrogenous as $T_1$ ) and 2% zeolite supplemented diet ($T_3$, supplemented to the control). Birds were housed in the batteries, and feeds and water were fed ad libitum. The results of Experiment 1 showed that birds fed control diet were heavier than those fed 2% zeolite supplemented diet up to 4th wks of age. However, birds fed the latter grew more at 5th and 6th wk. Overall weight gain, feed intake and feed efficiency were not significantly different. The results of Experiment 2 showed that there were no significant differences in weight gains, feed intakes and feed efficiencies among treatments during starter, finisher to overall period. The moisture levels in excreta of the birds were significantly (P＜0.01) less when zeolite was included in the diets and those in excreta significantly (P ＜ 0.01) increased as the ambient temperature increased. Economical efficiency expressed in fed cost (won) required per kg weight gin were 346.55 (T$_3$),348.34 ($T_1$ ) and 359.85 ($T_2$).

• Weed & Turfgrass Science
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• v.3 no.4
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• pp.370-377
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• 2014

Research was initiated to evaluate cool-season grass (CSG) overseeding effects on coverage and species transition in Korean lawngrass (Zoysia japonica Steud.) and to determine CSGs and their seeding rate for a practical overseeding. Treatments were comprised of Kentucky bluegrass (KB, Poa pratensis L.), perennial ryegrass (PR, Lolium perenne L.), tall fescue (TF, Festuca arundinacea Schreb.) and their mixtures. Significant differences were observed in turfgrass coverage and species transition. Since overseeding, the coverage was highest in PR, followed by TF and lowest in KB. The highest coverage in polystand was associated with Mixture IV (TF 50 + PR 50) at a seeding rate of $150gm^{-2}$ which had highest PR and TF, but without KB. Regarding turfgrass transition, zoysiagrass recovery continued to come back up to 80% from late March. But it reduced after early October. Zoysiagrass in monostand was greatest in KB and lowest in TF, but variable in polystand. For the fast and great coverage in winter, it would be the best to apply with PR at $100gm^{-2}$ and equal combination of PR and TF by 1/2 in the mixture at $150gm^{-2}$. For the smooth spring transition to zoysiagrass, however, KB application at $50gm^{-2}$ is recommended.

• Korean Journal of Food Science and Technology
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• v.24 no.4
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• pp.376-381
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• 1992

In order to study the effect of modified atmosphere storage on extending shelf life of mushrooms, oyster mushroom and Shiitake were wrapped with polyethylene film (PE, $50\;{\mu}m$), and stored at $0.5^{\circ}C$. Mushrooms packed with conventional hardboard box (4kg) lost marketability within $5{\sim}6$ days due to weight loss, shrinkage, browning, spore formation and/or mycellium growth. PE-packing could prevent or retard the deterioration of the mushrooms in the aspects of appearance, texture, discoloration, and microbial contamination. This situation can be best characterized by the reduced respiration rate resulted from the elevated level of carbon dioxide and the reduced level of oxygen in the bag. Although the appearance of the oyster mushroom was maintained for one month, its shelf life was limited to 15 days because of tissue softening. Discoloration of the pileus of shiitake mushroom appears to be the most important factor to determine its marketability. For example, extension of shelf life of Dongo was limited to 15 days, principally due to the browning of the pileus. Shelf life of Hawgo whose color of the pileus changed little over the experimental period, however, could be extened to more than one month.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.454-458
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• 2005

여름철 집중강우시 유입되는 고탁수층은 저수지의 밀도성층으로 인하여 표수층 하부에 위치하며, 이를 적기에 배제하지 않을 경우에는 수평방향의 확산현상과 연직방향의 전도현상으로 인해 저수지 전역에 분포하게 되어, 탁수현상의 장기화를 유발한다. 일본 사메우라댐의 경우에는 1977년 9월 태풍 17호에 의한 집중호우로 대량의 고탁수가 유입되어 하류하천으로의 댐 방류수의 고탁도현상이 장기간 지속된 바 있다. 이와 같은 탁수장기화에 대한 저수지내 대책의 하나로서 홍수유입후 탁도가 높은 물을 단기간동안 방류하고, 갈수기에는 탁도가 낮은 물을 방류하는 선택취수 개념이 제안된 바 있다. 국내의 임하댐의 경우에도 2002년 태풍 '루사'와 2003년 태풍 '매미'로 인해 발생한 탁수가 전도현상을 거치며 저수지내 전수층에 확산됨으로써 댐방류수의 고탁도현상이 장기화된바 있다. 이로 인하여 댐하류에 위치한 안동시 용상정수장의 동절기 정수처리 장애로 2003년 11월이후 약 160여일동안 댐방류가 중단된 바 있다. 임하댐의 경우에도 탁수장기화에 대한 대책으로서 홍수기 고탁수층을 우선배제한 후, 저수지내에 유입되는 청수을 담수함으로써 이를 방지할 수 있다. 이러한 선택취수 기법은 동일한 수리동역학적 개념을 적용하여 하류하천의 냉해문제를 대비하기 위한 방법으로 표층의 온수를 선택방류하는 데에도 이용될 수 있다. 이와 같은 선택취수를 효율적으로 수행하기 위해서는 취수시설에 접근하는 밀도흐름을 정확하게 이해하고 있어야 한다. 또한 취수탑 인근에서의 온도 및 탁도 등의 연직분포를 실시간으로 파악할 수 있는 자동수질측정시스템이 구축되어 있어야 한다. 현재 임하댐의 경우, 하류하천의 수질을 고려한 효율적인 탁수배제를 위하여 상류 유입부 2개소, 발전취수탑 전면 1개소, 조정지댐 1개소 등 총 4개의 자동수질측정시스템이 설치되어 탁도와 온도가 실시간으로 모니터링되고 있으며, 향후 강우시 저수지에서의 밀도흐름을 보다 정밀하게 모니터링하기 위하여 저수지내 4개의 주요지점에 추가적으로 설치될 예정이다. 이와 같은 자동측정시스템과 더불어 주기적인 세부 수질조사를 실시하면 저수지내의 온도성층 변화와 탁수층 분포를 매우 정확하게 파악할 수 있으며, 호소의 수질모형과 연계하여 강우시 탁수 도달시간과 탁수량을 사전에 예측할 수도 있다. 또한 이와 같은 기초적인 정보를 바탕으로 하류하천의 탁수 피해를 최소화할 수 있는 선택취수탑의 운영방안을 수립할 수 있다 본 연구에서는 이를 위해 선택취수탑 주위의 성층흐름을 기존의 실험자료와 수치해석을 통하여 분석하였고, 온도성층구조나 취수구의 위치변화에 따른 방류수 수질특성을 조사하였다.

• The Korean Journal of Mycology
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• v.27 no.2 s.89
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• pp.170-174
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• 1999

Water-soluble polysaccharides from the fruiting bodies of Agaricus blazei Murill were extracted with 0.9% sodium chloride and hot water, successively. The purified polysaccharides showed a potent immunostimulating activity. Eight major polysaccharides, which were named from AG-l to AG-8, were fractionated and purified by ethanol precipitation, ion exchange chromatography on DEAE-cellulose and gel filtration on Toyopearl HW 65F. These polysaccharides were identified to be homogeneous by analysis of HPLC. Three major active polysaccharides (AG-2, -3, and -6) showed relatively strong immunostimulating activity. AG-2 and -3 were composed of glucose, galactose and mannose in the molar ratios of 74.0:15.3:10.7 and 63.6:17.6:12.7, respectively. AG-6 was composed of glucose and ribose in the molar ratios of 81.4:12.6.

• Journal of Applied Biological Chemistry
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• v.53 no.1
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• pp.37-43
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• 2010

This study was carried out to determine the chemical quality properties during processing treatment using the brown rice varieties with different amylose content. It was investigated using Hwaseonchalbyeo, Baegjinjubyeo, Ilpumbyeo and Goamibyeo varieties. As for the chemical properties of fried brown rice, phenolic compounds increased by the frying treatment. The component of aroma after the frying treatment, it showed that aldehydes sorts of benzaldehyde, phenylmethanal had the highest content. The content of vitamin B group during parboiling treatment and frying treatment decreased as a whole than the non-treatment brown rice. The higher the content of amylose was, the more the content of vitamin $B_2$ increased. The higher the content of amylose was, the more the content of vitamin $B_6$ and mineral contents decreased. The component of mineral during frying treatment, it showed that Mg had the highest content. The higher the content of amylose increased, the more the blue value increased. The 2,2-diphenyl-$\beta$-picryl-hydrazyl (DPPH) after the frying treatment was relatively increased.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.5
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• pp.335-342
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• 2015

In this study, data linking module called GeoSWMM was developed using a typical secondary flooding model SWMM in order to improve the accuracy of the input data of SWMM and to map hourly inundation estimation areas that were not represented in the conventional inundation map. GeoSWMM is a data linking module of GIS and SWMM, which can generate a SWMM project file directly from sewer network GIS data. Utilizing the GeoSWMM the project file of SWMM model was constructed in the study area, Seocho 2-dong, Seoul. The actual flooding has occurred September 21, 2010 and the actual rainfall data were used for flood simulation. As a result, the outflow started from 2 PM due to the lack of water flow capacity of the sewage system. Based on the results, hourly inundation estimation maps were produced and compared with flood train map in 2010. The comparison showed about 66% matching in the overlap of inundation areas. By utilizing GeoSWMM that was developed in this study, it is easy to build the sewer network data for SWMM. In addition, the creation of hourly inundation estimation map using SWMM will be much help to flood disaster prevention plan.