• Korean Chemical Engineering Research
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• v.58 no.1
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• pp.84-91
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• 2020

The efficiency of the synthetic magnesium silicate used in basic polyols and edible oil purification is evaluated by its purification ability and filtration rate and is affected by the particle size and surface area of magnesium silicate. In this study, it was investigated the change on the particle size of magnesium silicate was influenced by the reaction temperature, injection rate, injection order (Si, Mg) and Mg/Si reaction mole ratio. The synthesized magnesium silicate was compared and analyzed for the synthesis, grinding, and refining processes. In the synthesis process, the reaction temperature and feed rate did not affect the average particle size change of magnesium silicate, while the reaction molar ratio of Mg / Si and the order of injection acted as main factors for the change of average particle size. The average particle size of magnesium silicate increased by 8.7 ㎛ from 54.4 ㎛ to 63.1 ㎛ at Mg injection when Mg molar ratio increased from 0.125 to 0.500, and increased by about 4.8 ㎛ from 47.3 ㎛ to 52.1 ㎛ at Si injection. The average particle size according to the order of injection was 59.1 ㎛ for Mg injection and 48.4 ㎛ for Si injection and the difference was shown 10.7 ㎛, therefore the filtration rate was about 2 times faster under the condition of Mg injection. That is, as the particle size increases, the filtration time is shortened and washing filtration rate can be increased to improve the productivity of magnesium silicate. The cake form of separated magnesium silicate after filtration becomes a solid through drying process and is used as powdery adsorbent through the grinding process. As the physical strength of the dried magnesium silicate increased, the average particle size of the powder increased and it was confirmed that this strength was affected by the reaction molar ratio. As the reaction molar ratio of Mg / Si increased, the physical strength of magnesium silicate decreased and the average particle size after grinding decreased by about 40% compared to the average particle size after synthesis. This reduction of strength resulted in an improvement of the refining ability due to the decrease of the average particle size and the increase of the amount of fine particle after the pulverization, but it resulted in the decrease of the purification filtration rate. While the molar ratio of Mg/Si was increased from 0.125 to 0.5 at Mg injection, the refining ability increased about 1.3 times, but the purification filtration rate decreased about 1.5 times. Therefore, in order to improve the productivity of magnesium silicate, the reaction molar ratio of Mg / Si should be increased, but in order to increase the purification filtration rate of the polyol, the reaction molar ratio should be decreased. In the synthesis parameters of magnesium silicate, the order of injection and the reaction molar ratio of Mg / Si are important factors affecting the changes in average particle size after synthesis and the changes of particle size after grinding due to the changes of compressive strength, therefore the synthetic parameter is an important thing that determines productivity and refining capacity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.1
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• pp.65-71
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• 1991

The purpose of this survey was to study Nutrition Status related to eating behabvior health status and nutrient intake. this survey was conducted for 100 students at Mokpo National University from semptember 25 to 29 in 1989. Average height and weight of students were found to be increased for last thirty years from 1957 to 1989. the average height of male and female were 172.0cm 160.1cm and the average weight of those were 63.4kg 48.2kg respectively. Health status showed fair. but most of students had symptoms such as stress cold and disorder of stomach. The main purpose of eating is to satisfy hungry and routinal work. Most students have had dietary problems such as irregularity of meal time and skipping meal. Most nutrients was intaken properly but some were under percentae of RDA. For the male the average intake of Calorie(84.5%) and Vitamin B2(93.3%) were lower than RDA for the frmale that of Calorie(81.7%) and Iron(80.6%) The ration of percent calorie of Carbohyd-rate : Protein : Fat from total calories in male was 65:15:20 and that of female was 64 : 15: 21 this result was properly approached to the Recommend Calorie Composition(Based on Recommended Allwances 5th ed. Korea FAO Assoc. 1989)

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.9
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• pp.243-271
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• 1998

The changes of life-style by improving the standard of living produce the development of food service industry. But, the consequence is that food waste also increase. I think that the problems about the food waste become more critical. There are some reports about counting the amount of remaining foods until now. But, I can not find reports about the calory analysis of the remaining foods. So, I analysis the amounts and calories of the food and remaining food served at the restaurants for the purpose of groping how to reduce the remaining food and conclude as follows. First, the average amount of the food giving to one person is 1007gm(from 300gm to 1367gm), and the average amount of the remaining food is 126gm(from 29gm to 172gm). Second, the average calory of the food giving to one person is 795.5kcal(from 464kcal to 1225kcal), and the average calory of the remaining food is 140.8kcal(from 29kcal to 289kcal). So, we gain 130kcal more than recommending calory to woman. Therefore, we need to studies of developing menu, controlling the amount of supplied food, and improving how to supply. Also we need to study about the using of food bank and publish and use about recycling of food waste.

• Korean Journal of Agricultural Science
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• v.32 no.2
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• pp.151-167
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• 2005

In this study, certain factors influencing cherry tomato were estimated using system equations. In addition, the amount of influence to income from each factor was estimated from both direct and indirect effects. Based on OLS(Ordinary Least Squares) estimation, path analysis and factor analysis were employed to overcome multicollinearity problems. Data used in this study is interviewed cross sectional data of 65 cherry tomato producing farm in Chungnam-do area. Average age of the producers is 46.5. Average year of the production is 8 years. Average farm size, productivity, and income are 1,123 pyong, 7,439kg/10a, 8,112,000won/10a, respectively. The business performance of the sample farms were above average, in terms of the diagnosis by "Standard Business Diagnosis for Cherry tomato". To identify the factors influencing productivity, 15, 19, and 25 independent variables were selected for the dependent variables of yield, price(quality), and business cost, respectively. Finally, yield, quality, and business cost variables were set as independent variables to explain income as dependent variable. As a result of main factor analysis, 10, 12, 15, and 16 factors were identified as main factors for yield, quality, business cost, and income, respectively.

• IEMEK Journal of Embedded Systems and Applications
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• v.13 no.2
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• pp.83-91
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• 2018

With the development of IT (Information Technology) technology, embedded system and network technology are combined and used in various environments such as military environment as well as everyday life. In this paper, we propose a new airdropped distributed mobility model (ADMM) modeling the dispersion falling of the direct shot of a cluster bomb, and we compare and analyze some representative MANET routing protocols in ADMM in ns-3 simulator. As a result of the analysis, we show OLSR routing protocol is promising in ADMM environment in the view points of packet delivery ratio (PDR), end to end delay, and jitter. In addition, we propose a new adaptation scheme for OLSR, AND-OLSR (Average Node Distance based adaptive-OLSR) to improve the original OLSR in ADMM environment. The new protocol calculates the average node distance, adapts the period of the control message based on the average node distance increasing rate. Through the simulation study, we show that the proposed AND-OLSR outperforms the original OLSR in PDR and control message overhead.

• Korean Journal of Veterinary Service
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• v.25 no.1
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• pp.15-22
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• 2002

This experiment was carried out to investigate the changes of egg qualify during storage in order to find out the proper storage condition. Fresh eggs were stored at cold condition ($5^{\circ}C$, relative humidity ; RH :$65\pm$3%) and room condition($25^{\circ}C$, RH :$40\pm$3%) during 10 weeks and examined microbiological quality, weight loss and interior quality periodically. Weight loss was indicated 17.93% at room condition and 2.56% at cold condition. The pH of egg white and yolk were increased from 7.94 to 9.03(average 13.72%) and from 6.16 to 6.57(average 6.65%) at cold condition and from 7.94 to 9.54(average 20.15%) and from 6.16 to 6.90(average 12.01%) at room condition respectively. But pH of egg white and yolk did not showed significant difference between before molting and after molting. Haugh unit was decreased from 82.0 to <30 at room condition after 3 weeks. The most frequent bacteria isolated were E coli, Staphylococcus leutus, S saprophyticus, Citrobacter freundii, Klebsiella oxytoca, Providencia rettgeri, and Pontoea spp. It was recommended that shelf life of unrefrigerated eggs would not be longer than 21 days at room temperature in summer.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.227-229
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• 2021

The modern society is advancing from the analog era to the digital imaging era, and in line with the trend of this era, various imaging devices such as exploration robots, medical equipment, and CCTV are helping our daily life a lot. However, noises caused by various causes in digital images not only cause image deterioration, but also deteriorate and deteriorate image quality. A typical noise is AWGN, and types of filters to remove it include an average filter, a median filter, and an alpha-trimmed average filter, but these filters have a disadvantage in that they show somewhat inadequate noise reduction performance in the high frequency region. Therefore, in this paper, a modified spatial division average filter based on standard deviation is proposed to effectively reduce AWGN existing in the high frequency region of the image.

• Journal of Life Science
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• v.19 no.2
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• pp.174-178
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• 2009

The characteristics of the population genetic structure of the Japanese anchovy (Engraulis japonicus Temminck & Schlegel) were collected from the West, South and East Seas of Korea in August, 2006 and were compared using six microsatellite DNA loci. In the West Sea population, the range of allele number against 72 individuals was from 19 to 41, the average allele number was 28.5. In EJ9, the allele number had the highest value of 41, this was 1.4 times higher than the average number of allele. The average allele number of the South Sea population was 24.5 that was less than that of West Sea population. In EJ2, EJ9 and EJ27.1 loci, the allele number was higher than average allele number in the South Sea population. In the East Sea population, the average allele number was estimated at 25.0 that most of loci except for EJ35 were higher than average allele number. Allele frequency in the West, South and East Sea populations was below 0.24. The value of observed heterozosity for six loci was approximately 0.5 higher than that of expected heterozosity (p>0.05), but three populations similar values to these heterozosity. Although the genetic diversity was higher value of above 0.9, three populations had a similar value. Genetic differentiation and distance combined estimate of the six loci were 0.258 and 0.019 (p>0.05), respectively, but showed no significant distance between three populations. These results suggested that it is responsible for no differentiated gene pool between three populations.

• Reproductive and Developmental Biology
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• v.29 no.4
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• pp.213-221
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• 2005

We used nine decamer primers to generate DNA fragment sizes ranging from 100 bp to 1,600 bp from two bullhead (Pseudobagrus fulvidraco) populations of Dangjin in Korea. 376 fragments were identified in the cultured bullhead population, and 454 in the population of wild bullhead from Dangjin: 287 specific fragments $(76.3\%)$ in the cultured bullhead population and 207 $(45.6\%)$ in the wild bullhead population. On average, a decamer primer was used to generate 34.2 amplified products in a cultured bullhead. A RAPD primer was used to generate an average of 3.1 amplified bands per sample, ranging between 2.5 and 6.0 fragments in this population. Nine primers also generated 24 polymorphic fragments (24/376 fragment, $6.4\%$) in the cultured bullhead population, and 24 (24/454 fragments, $5.2\%$) in the wild bullhead population. The OPA-16 primer, notably, produced which 11 out of 11 bands $(100\%)$ were monomorphic in the wild bullhead population. 110 intra-population-specific fragments, with an average of 12.2 per primer, were observed in the cultured bullhead population. 99 fragments, with an average of 11.0 per primer, were identified in the wild bullhead. Especially, 55 inter-population-common fragments, with an average of 6.1 per primer, were observed in the two bullhead populations. The bandsharing value (BS value) of individuals within the wild bullhead population was substantially higher than was determined in the cultured bullhead population. The average bandsharing value was $0.596\pm0.010$ within the cultured bullhead population,. and $0.657\pm0.010$ within the wild bullhead population. The dendrogram obtained with the nine primers indicates two genetic clusters, designated cluster $1\;(CULTURED\;01\~CULTURED\;11)$, and cluster $2\;(WILD\;12\~WILD\;22)$. Ultimately, the longest genetic distance displaying significant molecular differences was determined to exist between individuals in the two bullhead populations, namely between individuals WILD no. 19 of the wild bullhead population and CULTURED no. 03 of the cultured bullhead population (genetic distance = 0.714). RAPD-PCR allowed us to detect the existence of population discrimination and genetic variation in Korean population of bullhead. This finding indicates that this method constitutes a suitable tool for DNA comparison, both within and between individuals, populations, species, and genera.

• Journal of Digital Convergence
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• v.10 no.9
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• pp.417-427
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• 2012

This study is to recognize the relationship between better life index, nursing performance and intents to leave among hospital nurses by comparison. From July 1to July 20, 2012. we collected survey results subjecting on total 700 nurses by random sampling of hospital-class medical institutes over 200 beds located on Busan & Gyeongnam, and analyzed final 677 copies. We recognized the degrees and the differences of happiness index, professionalism, intents to leave among hospital nerses and analyzed the factors impacting on intents to leave among hospital nerses through correlation analysis and multiple regression analysis between variables. The main result is as follows: First, the average of the item related to happiness index of nurse was 3.03 (5 points of scale) and the average score of professionalism was 3.09 (medium degree) but the average score of turnover intention was 3.35 (relatively high); Second, professionalism and turnover intention according to characteristics of subjects were significant statistically (p<0.05) and turnover intention indicated a significant negative relation with happiness index and professionalism; Third, a factor which mostly impact on turnover intention indicated a significant level (p<0.05) in professionalism, happiness index, general hospital, 2.01 to 2.5 million of average pay. Based on such results, as happiness index and professionalism are indicated as major factors to turnover intention, multi-dimensional viewpoint of follow-up study including further variables is required and the plan to apply nursing intervention program for reducing turnover intention is also required.