• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.920-924
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• 2012

This study was performed to estimate total contents of arsenic (As) by stepwise multiple-regression analysis using chemical properties and extractable contents of metal in paddy soil adjacent to abandoned mines. The soil was collected from paddies near abandoned mines. Soil pH, electrical conductively (EC), organic mater (OM), available phosphorus ($P_2O_5$), and exchangeable cations (Ca, K, Mg, Na) were measured. Total contents of As and extractable contents of metals were analyzed by ICP-OES. From stepwise analysis, it was showed that the contents of extractable As, available phosphorus, extractable Cu, exchangeable K, exchangeable Na, and organic mater significantly influenced the total contents of As in soil (p<0.001). The multiple linear regression models have been established as Log (Total-As) = 0.741 + 0.716 Log (extractable-As) - 0.734 Log (avail-$P_2O_5$) + 0.334 Log (extractable-Cu) + 0.186 Log (exchangeable-K) - 0.593 Log (exchangeable-Na) + 0.558 Log (OM). The estimated value in total contents of As was significantly correlated with the measured value in soil ($R^2$=0.84196, p<0.0001). This predictive model for estimating total As contents in paddy soil will be properly applied to the numerous datasets which were surveyed with extractable heavy metal contents based on Soil Environmental Conservation Act before 2010.

• Korean Journal of Food Science and Technology
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• v.43 no.6
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• pp.791-794
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• 2011

The aim of this study was to investigate the antimicrobial characteristics of citral against Salmonella Typhimurium and Staphylococcus aureus. Antimicrobial activities were determined according to the citral concentration and initial pH. The tested citral concentrations were 0-1,000 ppm in tryptic soy broth (TSB) and 0-5,000 ppm in Angelica keiskei juice (NokJeup). The initial pHs tested were 4-7. Antimicrobial activities increased as citral concentration increased. S. aureus was more susceptible than S. Typhimurium during culture in TSB. But S. aureus was less susceptible to pH changes. Citral caused about 1-2 log reduction of S. aureus and 2-5 log reduction of S. Typhimurium after 10 min exposure at different pHs. As the citral concentration in the Algelica keiskei juice increased, S. aureus was easily inactivated but S. Typhimurium was not inactivated.

• Korean Journal of Food Science and Technology
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• v.45 no.6
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• pp.796-800
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• 2013

Soybean-based fermented foods have been used as traditional condiments in Korea, Japan and China. Thirteen Korean types of soybean sauce that had been manufactured and sold in China were examined to evaluate their quality. The pH, salinity, and moisture content of the samples were pH 5.17-6.86, 8.0%-23.0%, and 46.446-70.40%, respectively. The amino-type nitrogen content was in the range of 199.18 to 736.46 mg%. The total aerobic bacterial counts were 4.83-7.89 Log CFU/g. The coliform count of gochujang (CNH-2) was 2.31 Log CFU/g, but none were detected in the other samples. Moreover, Bacillus cereus counts from samples of doenjang and gochujang were in the range 2.00-4.09 Log CFU/g. The protease and amylase activity of samples were 379.02-781.36 unit/g and 5.29-63.27 unit/g, respectively.

• Food Science and Preservation
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• v.19 no.1
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• pp.12-18
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• 2012

In this study, 0, 20, 40, 60, 80, and 100% $Ulmus$ $pumila$ L. nonglutinous and glutinous sikhe were added to $Ulmus$ $pumila$ L. extracts for 15 days at $4^{\circ}C$, and for seven days at $25^{\circ}C$, to examine the extracts' storage properties and sensory characteristics. The results are as follows: (1) On the changes of pH and acidity during storage of $Ulmus$ $pumila$ L. nonglutinous and glutinous sikhe, both of them showed lower pH values with lower additive $Ulmus$ $pumila$ L. extract contents. The pH value continuously decreased with a longer storage period, and the acidity was higher with a lower concentration of $Ulmus$ $pumila$ L. extract. (2) The total microbial cell count during storage of $Ulmus$ $pumila$ L. nonglutinous and glutinous sikhe at $4^{\circ}C$ was 4.6-5.0 log CFU/g at 0 day. The sikhe to which $Ulmus$ $pumila$ L. extract was not added increased to 8.8-9.0 log CFU/g on the seventh storage day, while the sikhye to which 80 and 100% $Ulmus$ $pumila$ L. extracts were added were 7.8 and 6.9 logCFU/g, respectively. Thus, the total cell count was lower with a higher additive content of $Ulmus$ $pumila$ L. extract. The total cell count of the sikhe to which 0-60% $Ulmus$ $pumila$ L. extracts reached the maximum value on the seventh storage day and did not show any change thereafter. The total cell count of the sikhe to which 80 and 100% $Ulmus$ $pumila$ L. extracts were added, however, reached the maximum value on the 10th to 13th storage days, thus showing that the storage period was increased by $Ulmus$ $pumila$ L. At $25^{\circ}C$, the total cell count was 4.6-5.0 log CFU/g on 0 day and continuously increased during the storage period. It had increased to 8.9-9.5 log CFU/g on the seventh storage day, and no differences were shown according to the additive content of $Ulmus$ $pumila$ L. extract. (3) On the sensory characteristics of $Ulmus$ $pumila$ L. nonglutinous and glutinous sikhe, the $Ulmus$ $pumila$ L. nonglutinous sikhe to which 20% $Ulmus$ $pumila$ L. extract was added showed the highest overall-acceptability value ($4.23{\pm}0.95$), whereas the $Ulmus$ $pumila$ L. glutinous sikhe to which 40% $Ulmus$ $pumila$ L. extract was added showed the highest overall-acceptability value ($3.95{\pm}0.95$). The sikhe to which 20 and 40% $Ulmus$ $pumila$ L. extracts were added showed significantly high taste, flavor, sweetness, and overall-preference values (p<0.05).

• Journal of the Korean Geotechnical Society
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• v.21 no.5
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• pp.111-122
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• 2005

The data on the pile load tests performed on 35 large drilled shafts are analyzed to investigate the load-settlement characteristics of large drilled shafts embedded in bed rocks. Generally, the settlement of large drilled shafts embedded in bed rocks is too small to determine the ultimated load with application of the regulation in design code for either the total settlement or the residual settlement. Therefore, to determine the yield load of large drilled shafts embedded in bed rocks, p(load)-logS (settlement) curve method, which has been proposed originally for the driven pile, was applied to the investigation on the data of the pile load tests. This technique shows that the yield load can be determined accurately and easily rather than other conventional techniques such as P-S, logp-logS, S-logt, and P-S curve methods. An empirical equation is proposed to represent the relationship between pile load and settlement before the yield loading condition. And the settlement of piles was related with the depth embedded in rock as well as rock properties. Based on the investigation on the data of pile load tests, the resonable regulations f3r both the total settlement and the residual settlement are proposed to determine the yield load of large drilled shafts embedded in bed rocks.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.146.1-146
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• 2003

관능성과 기능성이 증진된 김치를 제조하기 위해 polyphenol 성분의 함량이 높은 녹차를 부재료로 첨가하는 방법에 따른 김치의 발효특성을 조사하였다. 김치의 발효특성을 비교 조사하기 위하여 1%의 녹차 물추출물를 함유하는 소금물로 절인 후 담근 김치(I), 절임배추를 1% 녹차 물추출물에 일정시간 침지 후 제조한 김치(II), 녹차 물추출물 1%를 양념과 혼합하여 담근 김치(III)의 3가지 방법으로 김치를 제조한 후 1$0^{\circ}C$에서 숙성시키면서 pH, 산도, 균수, 총 페놀함량 및 관능적 품질을 조사하였다. 대조구의 pH는 숙성중 I~III의 경우보다 낮았고, 산도의 경우도 pH와 역으로 pH의 결과와 일치하였다. 그러나 녹차처리방법에 따른 큰 차이는 보이지 않았다. 대조구의 총균수와 젖산균수는 각각 6.27~9.22 및 4.50~8.28 log cfu/mL로 I~III의 5.46~8.47 및 4.55~8.00 log cfu/mL보다 높았다. 총 폴리페놀 함량은 김치의 적숙기에 높게 나타났으며 control

• Journal of Korean Ophthalmic Optics Society
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• v.21 no.1
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• pp.47-51
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• 2016

Purpose: The purpose of this study was to investigate the change of contrast sensitivity by prescribing tinted lenses and to provide the clinical manual. Methods: Contrast sensitivity was measured for twenty adults with normal vision while they wore yellow, orange and green tinted lenses. To measure contrast sensitivity, the 5 spatial frequencies (2, 4, 6, 8 and 10 cpd) were used for 33 ms and 233 ms, respectively. Results: The contrast sensitivity was overall higher with 233 ms than 33 ms (p<0.05). The peaks of contrast sensitivity with 33 ms and 233 ms were 1.75 log unit with the yellow lens and 1. 85 log unit without the color respectively. However, there was no significance between the yellow and orange tinted lens (p>0.64) Conclusions: Yellowish tinted lens that reduces chromatic aberration and the scattering is prescribed for the various purposes to improve visual functions. Before prescribing tinted lens, identifying characteristic of user and tinted lens for cut off wavelengths is recommended.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.8
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• pp.1176-1181
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• 2012

This study was conducted to examine changes in the microbial and physicochemical properties of single-brewed Makgeolli in response to high hydrostatic pressure (HHP) treatment during various fermentation stages. HHP was applied in 2-day intervals at 400 MPa for 5 min during fermentation at $25^{\circ}C$. As a result, lactic acid bacteria showed 5~6 log reduction and reappeared at approximately 3~6 log cfu/mL as fermentation proceeded. Yeast also showed 5~6 log reduction but did not reappear during later fermentation period. HPP treatment did not result in any alcohol production on day 0 and 2. However, HPP treatment altered the pH and titratable acidity by reducing the number of microorganism. Reducing sugar contents of the samples increased continuously to 8.99% in 0 day treated sample and 5.01% in 2 day treated sample, whereas untreated Makgeolli contained 1.53% reducing sugars on 6 day due to alcohol conversion by yeast. Based on these results, HPP treatment during various fermentation stages altered the physicochemical properties of Makgeolli by changing the microbial community.

• Journal of Digital Contents Society
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• v.12 no.1
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• pp.133-139
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• 2011

Structured P2P (peer-to-peer) networks have received much attention in research communities and the industry. The data stored in structured P2P networks can be located in a log-scale time without using central severs. The link-structure of structured P2P networks should be maintained for keeping log-scale search performance of it. When nodes join or leave structured P2P networks frequently, some links become unavailable and search performance is degraded by these links. To sustain search performance of structured P2P networks, periodic link recovery scheme is generally used. However, when the link recovery period is short or long compared with node join and leave rates, it is possible that sufficient number of links are not restored or excessive messages are used after the link-structure is restored. We propose the adaptive link recovery determination algorithm to maintain the link-structure of structured P2P networks when the rates of node joining and leaving are changed dynamically. The simulation results show that the proposed algorithm can maintain similar QoS under various node leaving rates.

• Journal of Animal Science and Technology
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• v.44 no.3
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• pp.361-368
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• 2002

The Korean frozen pork loins in vacuum packaged were obtained from three different Korean export companies and investigated for pH, proximate composition, cooking loss, physico-chemical and sensory characteristics. The frozen pork loins were stored at -20$^{\circ}C$ for 40 days. The results were as follows: The protein contents were relatively higher in the samples from the company II and the ash contents were relatively higher in the samples from the company I than those from the other companies. The samples from the company Ⅱ had highest pH and water-holding capacity, and cooking loss and shear force were lowest in the company II. The total plate counts and coliform bacteria for loins from 3 companies were in the range of 3.04${\sim}$3.75 log cfu/$cm^2$ or g and 0.37${\sim}$1.32 log cfu/$cm^2$ or g in average, respectively. The TBARS values were 0.35${\sim}$0.38 mg malonaldehyde/kg sample. There were no significant differences in sensory characteristics for raw and cooked loins from all companies.