• Journal of Food Hygiene and Safety
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• v.31 no.5
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• pp.342-348
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• 2016

The objective of this study was to compare the change of S. Enteritidis with S. Typhimurium populations in liquid egg products. S. Enteritidis or S. Typhimurium was inoculated into egg white and egg yolk and stored at 8, 10, 15, 25, and $35^{\circ}C$, respectively. In egg white, no growth of S. Enteritidis and S. Typhimurium was observed at 8, 10, 15, and $35^{\circ}C$, while both S. Enteritidis and S. Typhimurium in egg white stored grew more than 1 log CFU/ml after 50 hours storage at $25^{\circ}C$. In egg yolk, there was no growth of S. Enteritidis and S. Typhimurium at $8^{\circ}C$ but growth of both strains was observed at 10, 15, 25, and $35^{\circ}C$. Since growth of S. Enteritidis and S. Typhimurium was only observed in egg yolk, primary growth models for both strains were developed using modified Gompertz equation and then secondary models for lag time (LT), specific growth rate (SGR), and maximum population density (MPD) were developed as a function of temperature. At all temperatures, more rapid growth of S. Enteritidis than S. Typhimurium was observed in egg yolk, indicating the greater risk of S. Enteritidis than S. Typhimurium in egg products. In conclusion, the results indicate that temperature control less than $8^{\circ}C$ is very important to ensure safety of liquid egg products, especially liquid egg yolk.

• Korean Journal of Plant Tissue Culture
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• v.22 no.5
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• pp.261-266
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• 1995

This study was carried out to develop new varieties which are dwarf and tolerant to winter cold in the Aurantioideae by intergeneric crossing. to do that, the reciprocal crosses of Hwanggeumyooza and trifoliate orange, yooza and trifoliate orange were done and in vitro immature ovule culture of their hybrid was carried out .The callus formation from immature ovule was good in order of Hwanggeumyooza, Hwanggeumyooza $\times$ tifoliate orange, yooza, and trifoliate orange and best at 1 to 3 mg/L NAA+0.5mg/L zeatin on MT medium. In vitro germination percentage of 20week old hybrid of Hwanggeumyooza $\times$ tifoliate orange and trifoliate orange $\times$ Hwanggeumyooza were 41.3% and 37.7, respectively. The phenotype of hybrid (95%) of Hwanggeumyooza $\times$ trifoliate orange and that (100%) of trifoliate orange $\times$ Hwanggeumyooza were similar to that of trifoliate orange. After Hwanggeumyooza was pollinated by pollens of trifoliate orange, the pollen tubes grew on stigma after 3h of pollination and entered into micropyle after about 24~28 h. One gamete in pollen was fused with polar nuclei after 2 days and other one fused with egg nucleus at 3days after pollination. The fruit set percentage by intergeneric crossing was 14.0% in Hwanggeumyooza $\times$ trtfoliate orange and 17.5% in trifoliate orange $\times$ Hwanggeumyooza. The fruit set percentages of Hwanggeumyooza. and trifoliate orange were 34.2% and 39.5% by artificial self-fertilization, 34.2% and 39.5% by artificial cross fertilization, 3.1% and 1.4% by parthenocarpy and 13.0% and 3.0% by natural fertilization, respectively. The somatic and gametic chromosome numbers of Hwanggeumyooza, yooza, and trifoliate orange were 2n=18 and n=9.

• Journal of Korean Society of Transportation
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• v.26 no.1
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• pp.215-223
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• 2008

Due partly to lack of actual lane-changing data and partly to few studies on simulation functions to consider the lane-changing behavior, it may result in significant difference between simulation-based and real conditions. The objectives of this study are to estimate the set of mandatory lane-changing models and to analyze their features, depending on the merge control strategies under the lane-closed work zone operations. To achieve them, first, the elaborated calibration is required to simulate the mandatory lane-changing behaviors with the actual field data. Second, one can estimate their models with the logistic regression models, to obtain traffic variables as well as the lane-changing frequencies under the various levels of work zone traffic conditions. As a result, one can state that the well-calibrated simulation has the potential to properly reflect the target mandatory lane-changing behaviors. In addition, it should be mentioned that the set of proposed models is not practicable but preliminary result needed to identify the relations between the actual traffic conditions and lane-changing maneuvers and to develop their practical models for the actual applications.

• Journal of Korea Water Resources Association
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• v.44 no.4
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• pp.305-314
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• 2011

Imnam Dam construction and inter-basin water transfer use by North Korea have caused several problems including water resources management aspects in the downstream reach of North Han River. Therefore, cooperative works between North and South Korea are required to make a reasonable management situation of the shared river for water quantity and quality. However, efforts by the North and the South has done not enough to achieve equitable water use in the shared river. This study analyzes main impacts caused by Imnam Dam in key sectors for reviewing water use right regarded as the most important decision-making criterion in international rivers. As the results, water deficit by Imnam Dam is calculated at 379 million $m^3$/year when river drought year for water assessment is set in 1978 in the Han River basin. Additionally hydropower production is decreased by 234 GWh/year in exclusive hydropower generation dams. In respective of water quality, BOD concentration is increased by 0.065 ppm at Sambongli in North Han River. Finally it is identified that unequitable water use based on the absolute territorial sovereignty by North Korea in North Han River has directly and indirectly affected severe impacts to South Korea as the downstream user.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3135-3140
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• 2010

A 5 kWh composite flywheel rotor was designed and manufactured, and its spin test was performed to monitor strain distribution and burst speed. Strain distribution in radial and circumferential directions of the rotor were measured using a wireless telemetry system based on bluetooth technology for real-time strain measurement. The strains was compared with pre-calculated design values to verify the initial rotor design. We noticed the rotor failed at 19,499 rpm in the spin test, 11 % lower than the predicted burst speed of 22,000 rpm. Failure occurred at the hub which connects the shaft and the composite rotor. The performance of the composite rotor was confirmed in a general sense, and the danger of unexpected failure of composite rotor during high-speed spinning was also demonstrated in this paper. Special attention should be paid to not only composite rotor but also hub when designing a flywheel energy storage system. The telemetry system needs to be further developed, especially enduring the high centrifugal forces, and can be used in a real time monitoring system for the flywheel energy storage system.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.624-627
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• 2004

본 연구는 동일한 병렬기계에서의 총 납기지연의 합을 최소화하는 일정계획 문제에 대해 다룬다. 이 문제는 Lenstra et al. (1977)에 의해 NP-hard로 알려져 있으며, 작업의 수와 기계의 수가 큰 현실적 문제에 대해 적절한 시간 내에 최적해를 찾는다는 것은 사실상 불가능하다. 따라서 본 연구에서는 이 문제를 해결하기 위하여 혼합형 유전 알고리즘(hybrid genetic algorithm)을 제안한다. 혼합형 유전 알고리즘에서는 임의로 발생시킨 모집단에 대해 먼저 유전 알고리즘(genetic algorithm)이 세대를 진행하며 해를 개선한다. 유전 알고리즘이 일정기간동안 더 이상 해를 개선하지 못하면, 부분탐색 알고리즘(local-search algorithm))이 유전 알고리즘의 모집단의 개체들에 대해 해의 개선을 시도한다. 즉, 부분 탐색 알고리즘은 모집단 속의 각각의 개체를 초기해로 하여 모집단 내의 개체 수만큼의 부분 최적해(local optimum)들을 구한다. 이렇게 구한 부분 최적해들로 새로운 모집단을 구성하면 다시 유전 알고리즘이 진행된다. 이 과정을 종료조건에 이를 때까지 번갈아가며 반복 수행한다. 본 연구에서 제안한 유전 알고리즘에서는 Bean(1994)이 제안한 Random key 방법으로 개체를 표현하였으며 Park(2000)이 제안한 3가지 교차 연산자들을 채용하였다. 부분탐색 알고리즘을 위해서는 쌍대교환(pair-wise interchange) 방법을 통해 이웃해를 생성하였다. 선행실험을 통하여 제안한 혼합형 유전알고리즘에서 사용하는 다양한 모수(parameter)값들을 최적화하였으며 알고리즘의 성능을 비교하기 위하여 기존의 알고리즘과도 비교실험을 수행하였다.복적인 지표가 채택되는 경우를 포함하고 있다. 셋째는 추상적이며 측정이 어려운 지표를 채택하고 있는 경우이다. 여기에는 지표에 대한 정확한 정의가 이루어져 있지 않아 피 평가자가 불필요하거나 과다한 평가 자료를 준비해야 하거나 평가자로 하여금 평가 시 혼돈을 유발할 가능성이 있거나, 또는 상위개념의 평가항목과 하위개념의 평가항목이 혼재되어 구분이 모호한 경우를 포함하고 있다. 바탕으로 '생태적 합리성'이라는 체계적인 지식교육을 거쳐서, '환경정의' 의식의 제고로 이어가고, 굵직한 '환경갈등'의 상황에서 뚜렷한 정치적 태도와 실천을 할 수 있는 '생태적 인간상'의 육성으로 나아갈 수 있어야 한다는 것이 필자의 생각이다. 이를 위해서는 어찌되었건 체험학습 영역에서는 환경현안에 대한 사회적 실천을 '교육 소재'로 삼을 수 있어야 하며, 교과학습 영역에서는 한국사회의 환경현안에 대한 정치경제적 접근을 외면하지 말고 교과서 저작의 소재로 삼을 수 있어야 하며, 이는 '환경관리주의'와 '녹색소비'에 머물러 있는 '환경 지식교육'과 실천을 한단계 진전시키는 작업으로 이어질 것이다. 이후 10년의 환경교육은 바로 '생태적 합리성'과 '환경정의'라는 두 '화두'에 터하여 세워져야 한다.배액에서 약해를 보였으나, 25% 야자지방산의 경우 50 ${\sim}$ 100배액 어디에서도 액해를 보이지 않았다. 별도로 적용한 시험에서, 토마토의 경우에도 25% 야자지방산 비누 50 ${\sim}$ 100배액 모두 약해를 발생하지 않았으나, 오이에서는 25% 야자지방산 비누 100배액에도 약해를 나타내었다. 12. 이상의 결과, 천연지방산을 이용하여 유기농업에 허용되는 각종의 살충비누를 제조할 수 있었으

• Food Science and Preservation
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• v.17 no.4
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• pp.563-570
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• 2010

We sought to ferment wine from mulberry (Morus alba) juice. The soluble solid content was $9.5{\sim}14.5^{\circ}brix$ on day 6 of fermentation, and gradually fell later; sugar was not further consumed when $3^{\circ}brix$ was attained. Alcohol content rose dramatically on day 6 of fermentation, being 4.5% (v/v) at fermentation temperatures of 16C and 18C, 6.5% (v/v) at 20C, and 8.0% (v/v) at 25C, rising further to 10.5~11.5% (v/v) on day 48, at higher culture temperatures. Citric acid, malic acid, and oxalic acid were present in mulberries. The levels of both citric and oxalic acid fell after fermentation, whereas malic acid concentration increased. All of fructose, glucose, maltose, and sucrose were fermented. Electron-donating ability (EDA) was elevated to over 90% of the control value in mulberry juice diluted to 40% (v/v). SOD-like activities in juice and wine were 80.1% and 72.1% of the control value. Nitrite-scavenging abilities (NSAs) were 86.2% and 85.2% of control in undiluted juice and wine, respectively. Mulberry juice had an activation level higher than that of mulberry wine, but functionality neither rose nor fell after fermentation. Insensory evaluation, the overall wine score was better than average, at 5.00, demonstrating the commercial potential of mulberry wine.

• Food Science and Preservation
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• v.17 no.4
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• pp.547-554
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• 2010

We developed watermelon (Citrullus vulgaris Schrad) wine to increase the market for the fruit, which is currently sold only in fresh form. The pH of watermelon wine was pH 2.8~3.4, the total acid level 0.48~0.55%, and the soluble solid $5{\sim}6^{\circ}brix$ alcohol content was 9.5~10.5%. Fermentation of watermelon juice was satisfactory at both 20C and 25C. All of citric acid, malic acid, and oxalic acid were detected in watermelon wine citric acid was the most abundant. All of glucose, fructose, sucrose, and maltose were present in juice, and both fructose and glucose were used in fermentation. Electron-donating ability (EDA) was high, being 80% of the control value when watermelon wine was diluted to $400\;{\mu}l/ml$. SOD-like activities were present in both watermelon juice and wine, being 55.2% and 49.2% of control values, respectively. Nitrite-scavenging ability (NSA) was 70.2% and 53.2% of control values in undiluted juice and wine, respectively. Watermelon juice showed higher activation than did wine, but functionality neither fell nor rose after fermentation. In sensory evaluation of wine, the overall score was better than average, at 4.15, thus establishing the commercial potential of watermelon wine.

• Journal of the Korean Society of Radiology
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• v.3 no.4
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• pp.13-21
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• 2009

The Magnetic Resonance Imaging (MRI) systems consist of various parameters. Among them, the image quality can be arguably the most important part of the systems. As the other components in MRI systems have been developed and evolved, the MRI image quality has been advanced remarkably. And, the radiation imaging system is being converted from the Film to the digital method, which drives the computerization of many hospitals. The management of the tremendous radiation images becomes more critical. The data compression is used to store such large data in a network server. When the image files are compressed, the image quality degrades comparing to its original images. Even slight quality degradation of a medical image could cause an erroneous diagnosis, so the images must be handled carefully. This thesis studied the image assessment methods of comparing the quality of the compressed image to its original, and the quality of the original and the displayed images of the MRI systems via PSNR with actual medical images used in hospitals. As a result, no noticeable quality degradation was found comparing the compressed images with various digital compression methods and the original images. However, it was a different story comparing the original images and the displayed images on MRI monitors. Some noise or image distortion was visible using any regular CRT or LCD monitors were used while the special monitors designed for the MRI imaging and medical images displayed high definition images.

• Journal of Science Education
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• v.37 no.1
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• pp.170-185
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• 2013

The purpose of this study is to investigate a cognitive model of task commitment on biology classification inquiry. To achieve this goal, first, this study analyzed several literatures on task commitment in biology inquiry, and invented the tentative model of the task commitment. To investigate a tentative model invented, 2 main tasks were developed. These tasks were administered to 8 high-school students, first grade. Raw protocols were collected by thinking aloud method and a retrospective interview method. Collected protocols were converted to segmented protocols and coded by analyzing frame based invented model. The codes were analyzed. As a result, some problems were discovered, tentative model were revised. New analyzing frame based on Improved model were composed, and raw protocols were re-analyzed. Finally, a cognitive model of task commitment on biology classification inquiry was investigated. The investigated cognitive model of task commitment on biology classification inquiry was constructed 3 steps, 'Task commitment Induction', 'Task commitment Reinforcement', 'Task commitment Maintenance'. And each steps were consisted of several sub-factor. And commitment component were changed in each steps. Through this results, base information for strategy that improvement task commitment on biology classification inquiry is provided. Furthermore, the cognitive model of task commitment on biology classification inquiry will assist on evaluation and feedback by stage on task commitment.