• The Transactions of the Korea Information Processing Society
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• v.13 no.6
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• pp.251-259
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• 2024

Fine particulate matter, especially PM2.5 with a diameter of less than 2.5 micrometers, poses significant health and economic risks. This study focuses on the Seoul region of South Korea, aiming to analyze PM2.5 data and trends from 2017 to 2022 and develop a mid-term prediction model for PM2.5 concentrations. Utilizing collected and produced air quality and weather data, reanalysis data, and numerical model prediction data, this research proposes an ensemble evaluation method capable of adapting to trend changes. The ensemble method proposed in this study demonstrated superior performance in predicting PM2.5 concentrations, outperforming existing models by an average F1 Score of approximately 42.16% in 2019, 58.92% in 2021, and 34.79% in 2022 for future 3 to 6-day predictions. The model maintains performance under changing environmental conditions, offering stable predictions and presenting a mid-term prediction model that extends beyond the capabilities of existing deep learning-based short-term PM2.5 forecasts.

• Korean Journal of Poultry Science
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• v.31 no.4
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• pp.299-306
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• 2004

The objective of this study was to investigate the influence of egg storage, broiler breeder age, and the change of egg weight during incubation on growth rate of chicks and 43-day-old dressing percentage. The trials involved hatching eggs obtained from 27-wk-old hens and stored for 6 d for the Young-EXP group, from 28-wk-old hens and stored for 0 d for the Young-CON group, from 51-wk-old hens and stored for 6 d for the Old-EXP group, and from 52-wk-old hens and stored for 0 d for the Old-CON group, The hens were two commercial broiler breeder flocks of the same strain (Cobb) but of different egg producing stages(early and middle stages of egg production). The chicks were grown on floor pens for 6 wks, The differences of setting egg weights between Old-CON and Old-EXP groups were 1 g, but those between Young-CON and Young-EXP groups were 2.9 g(P<0,05). The loss of egg weight during 18 d incubation did not greatly differ among four groups, but the loss of egg weight during 21 d incubation was significantly (P<0.05) more in the middle stage of egg production groups than in the early stage of egg production groups. The mean birth weights of the middle stage of egg production groups were significantly(P<0,05) heavier by 8,7 g than those of the early stage of egg production groups; however, the differences of 6-wk-old body weight were not significant between egg producing stages. The differences of body weights in both egg producing stages were not significantly influenced by egg storage period in overall wks of ages. Egg storage and hen age did not greatly influence to the 43 d dressing percentages, either, The correlations of the setting egg weight with 18 d egg weight during incubation, growth rate of chicks, or 43 d dressing percentage were not significant.

• Journal of Animal Science and Technology
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• v.50 no.2
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• pp.199-208
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• 2008

This study was undertaken to investigate the effects of ruminally protected amino acids (Methionine and Lysine) on in vitro ruminal parameters, and in vivo milk yield and milk composition in mid-lactating cows. In the first in vitro experiment, there were no statistical significances between treatments in ruminal pH and dry matter digestibility during various incubation times. In the second in vivo experiment, milk yield decreased by 11.92% in control and 5.68% in the treatment respectively, but decrease rate of milk yield in the treatment was lower than control. Milk yields naturally decreased as time goes by since the DIMs(Days in milk) of the cows in experiment were in mid-lactation period. 4% FCM(Fat corrected milk) and milk protein yields also, respectively, decreased by 11.25% and 11.09% in control and 6.16% and 5.47% in the treatment as compared with the intial. Milk protein and milk fat production were higher in the treatment(0.90kg, 1.10kg) than those of control(0.66kg, 0.79kg). Milk fat content significantly increased with supplementing protected amino acids as compared to control(P<0.05). From the above results, protected amino acids were positively utilized in the performances of mid-lactating cows without inhibiting rumen fermentation. Further investigation is suggested for essential amino acid composition and intestinal digestion rate out of rumen bypass protein in dietary protein to be estimated.

• Journal of Animal Science and Technology
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• v.48 no.1
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• pp.123-130
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• 2006

Principal aim of this study is to suggest the statistical equation model which can predict an amount of ammonia emission according to the degree of compost maturity during composting livestock manure. Composting process was classified with intial, midterm and final phase based on germination index of compost samples. Total Kjeldahl nitrogen(TKN) and organic matter(OM) were selected as the independent variables available to contribute to ammonia emission from composting pile. Ammonia concentration measured in the samples taken at the intial phase was about 10ppm, sharply increased to 50ppm at the midterm phase, and gradually decreased to about 10ppm. The contents of Total Kjeldahl nitrogen and organic matter through whole composting period were ranged from 0.6 to 1.2% and from 30 to 40%, respectively, were reduced slightly at the midterm phase, but generally showed no constant fluctuation pattern. In estimating ammonia emission with application of the statistical equation model, the coefficients of independent variables at the midterm phase when an average concentration of ammonia was highest showed a relatively high values whereas those at the initial phase when an that of ammonia was lowest indicated a relatively low values. However, no statistical significance was found in the coefficients of independent variables and the equation model. Additionally, the further research, which can include the considerable analysis data with more samples taken than this study, is needed in order to suggest the statistically significant equation model available to predict ammonia emission during composting process.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.2
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• pp.166-173
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• 1991

In order to determine the relationships between the rates of leaf senescence and photosynthate translocation during the grain filling periods in barley, field experiments were conducted through 1989/1990 crop year. Thirty barley varieties and lines having different leaf senescence were used for the experiments. Varieties differed significantly in the rate of leaf senescence and rate of grain filling. The rate of leaf senescence at early (10-20days after heading) and late period (20-30days after heading) during of grain filling were positively correlated with the rate of grain filling in same period, respectively. But the rate of leaf senescence at 10-20 days after heading negatively correlated with the rate of grain filling during the whole grain filling period (10-35 days after heading). Whereas, the rate of leaf senescence at late period was positively associated with the rate of grain filling during the whole grain filling period. Rates of grain filling at the late and whole periods have positively influence on grain weight(r=0.62**～-0.93**), but rate of leaf senescence at early period and duration of grain filling negatively correlated with the grain weight (r=-0.33～ -0.15). The patterns of leaf senescence index for the varieties tested were grouped by four. Among these patterns, the most ideal pattern was IV type.

• Management & Information Systems Review
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• v.28 no.4
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• pp.155-174
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• 2009

The purpose of this paper is to analyze the stock market performances CAR of reorganized firms and study the disclosure effect of completion of reorganization to examine whether there exists significant economic merit for the institutionalized continuation of unprofitable firms. The main results of this paper can be summarized as follows. First, the average stock market performances for +12 months after the completion of reorganization compared to those for -6 months before the proposal of reorganization show consistently negative returns. Second, to see whether there exist significant differences between the stock market performances of reorganized firms and those of normal firms with similar characteristics, CAR's measured from -6 months before the proposal of reorganization to +12 months after the completion of reorganization are statistically tested, which results in significantly negative values starting +5 months after the completion of reorganization. Finally, to see the disclosure effect of the news of completion of reorganization, daily CAR's are measured and tested, which shows positive values only for -20 days and -19 days before the disclosure, and shows negative values for the whole periods up to +20 days after the disclosure. The results of the paper imply consistently that the reorganized firms have no better performances compared to the similar normal firms, and the performances do not improve even after the completion of reorganization, which casts serious doubts upon the current forms of the institutionalized continuation of unprofitable firms.

• Journal of Chest Surgery
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• v.37 no.6
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• pp.530-535
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• 2004

Background: Thoracoscopic R3 (above the third rib)sympathicotomy has been performed as an effective method in treating palmar hyperhidrosis because it is effective in eliminating the symptoms of hyperhidrosis and has lower degree of compensatory hyperhidrosis than that of sympathectomy. Most of the results published were based on the short-term follow up. So we evaluated the intermediate term follow up results of the R3 sympathicotomy. Material and Method: From April 1999 to August 2001, ninety-four patients with palmar hyperhidrosis had been treated by R3 sympathicotomy at the Inha University Hospital. Follow-up study was completed for 76 patients (male 38, female 38) and average follow-up period were 25$\pm$9.1 (15∼50) months. The sympathetic trunk passing above the upper border of third rib was divided by electric cautery. The patient's satisfaction after surgery was estimated using the analogue scale from score 0 to 100 (100 means perfect satisfaction). Result. The scale of patient's satisfaction immediately after operation was 92.36$\pm$9.93. After 15 months, the scale of satisfaction was decreased to average 71.80$\pm$20.24 and it is statiscally significant. The cause of dissatisfaction were compensatory hyper-hidrosis and recurrence of symptom. The degree of sweating immediately after operation was mean 0 and after 15 months it increased to mean 1.5. The degree of the compensatory hyperhidrosis immediately after operation was mean 1 and it increased to mean 5 after 15 months. Conclusion: R3 sympathicotomy has excellent therapeutic results immediately after operation but therapeutic effectiveness is becoming to decrease 15 months after operation. The common causes of dissatisfaction are compensatory hyperhidrosis and recurrence of hyperhidrosis.

• Korean Journal of Animal Reproduction
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• v.18 no.2
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• pp.87-94
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• 1994

The objective of this study is to evaluate the developmental ability of mouse embryo in the presence of human amniotic fluid (hAF), The highest development rate was found in the culture media supplemented with 20% mid-term hAF but this rate was concomitantly reduced with more than 20% hAF. Furthermore, mouse two-cell embryos cultured in 20% mid-term hAF were developed more consistently to the expanded and hatched blastocyst stages compared to those cultured in simple medium. However, no significant differences in the embryo development rates were observed among the supplemented effects of 20% mid-term hAF, 0.3% bovine serum albumin (BSA), and 10% fetal calf serum (FCS), Development rates of two-ceiI mouse embryos cultured in 20% full-term hAF were declined compared to 20% mid-term hAF. Outgrowth of hatched blastocysts were observed when the embryos were cultured in medium containing 20% mid-term hAF or 10% FCS. But two-cell mouse embryos cultured in the presence of 20% full-term hAF or O.3% BSA was not observed their outgrowth. The kinetics of outgrowth processes in the presence of hAF were similar to those with 10% FCS. However, embryos with FCS showed a considerably greater extents of trophetodermal cell proliferation and outgrowth. Taken together, these data suggest that mid-term hAF may have a suitability for the mammalian embryos and induce embryonic outgrowth.

• Journal of Korea Technology Innovation Society
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• v.10 no.3
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• pp.509-530
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• 2007

This paper examined the relationship between innovation and firm performance by integrating industry competitive context and firm-level knowledge constructs. After controlling for firm site, age, and the presence of a union, cross-section analysis of survey data from 1,419 medium sized manufacturing firms yielded following findings. The first was the expected positive relationship between firm-level innovation and firm knowledge and also industry dynamism, as measured by the intensity of industry-level R&D. This results indicate that industries with greater aggregate levels of R&D intensity are home to higher rates of firm-level innovative activity and managers must increase their numbers of technical staff and the level of training. But the interaction between firm knowledge and industry dynamism was non-significant. Second, innovation was not significantly related to firm performance, as measured by revenue growth. This relationship was not moderated by industry dynamism and firm level knowledge. In high and low technology sectors, the relationship between innovation and performance was non-significant, consistent with the full-sample analysis. The results suggest that the effects of firm-level knowledge assets and investments in training don't work in different ways in different industry settings. This research used three control variables to analyze innovation and firm performance. Firm age was negatively associated with firm performance and did not significantly predict innovation. Firm size was positively associated with innovation and performance in the low-technology sector. The presence of a labor union was not a significant with respect to innovation.

• Journal of the Korean earth science society
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• v.22 no.6
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• pp.558-570
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• 2001

The Middle Carboniferous Manhang and Geumcheon Formations exposed in the Taebaek area, Kangwondo, Korea consist of sandstones and shales with some intercalation of limestone beds. The limestones of the formations contain abundant conodonts and other fossils. The purpose of this study is (1) to investigate the conodont fauna, (2) to assign conodont biozones of the Manhang and Geumcheon Formations, and (3) to refine their geologic age more exactly. The conodonts of the Manhang and Geumcheon Formations are 6 genera distributed into 11 species. Conodonts found from limestones of the Manhang Formation are Idiognathodus delicatus, Hindeodus minutus, Streptognathodus sp., Diplognathodus coloradoensis, N. bothorops, and N. medexultimus. This conodont fauna can be assigned to the Neognathodus bothrops Zone. This conodont biozone indicates that the geologic age of the Manghang Formation is the Atokan stage of the Middle Carboniferous Period. Conodonts came from limestones of the Geumcheon Formation are Idiognathodus delicatus, N. medexultimus, N. roundyi, N. dilatus, Diplognathodus edentulus, Hindeodus minutus, Streptognathodus elegantulus, and Gondolella bella. These conodonts permit them to be assigned to the Neognathodus roundyi Zone. This Conodont biozone indicates that the geologic age of the Geumcheon Formation is the Desmoinesian stage of the Middle Carboniferous Period.