• Journal of Biosystems Engineering
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• v.2 no.2
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• pp.37-45
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• 1977

Solar energy is a potential source of power that offers much promise being used for low-temperature applications like drying farm crops, space heating, and water heating for domestic uses. Already much of it are being used for those purpose in foreign countries. However, very little research has been done to determine the possibility of using the solar energy in Korea. This study was conducted to develop the general prediction equation of the total radiation on a horizontal surface in Daejeon area based on 5 years 91972, Jun.1-1976. Dec.31) meteorological data (bright sunshine hours, average total horizontal radiation), and to obtain experimentally the thermal efficiency of solar air and water collectors, which will be used as a basic data of designing flat-plate solar collector system.In addition to the thermal efficiency of the collectorsthe relationship among those factors affecting it such as weather condition, orientation factor, and tilted angle of collector was analyzed. The results of this study were as follows. 1. The general predicted equation of the total radiation on a horizontal surface in Daejeon area based on bright sunshine hours was developed as $H_{av} =(1.546\frac{n}{N}-0.582)H_o$. Predicting the total radiation on a horizontal surface by the above equation was thought to be possible because to values of 0.882 was smaller than any t values at above 0.05 level on the basis of two tailed test of the difference between the calculated and the recorded values. 2.It was observed that optimum tilt angle of the collector in the summer and the autumn drying season was 13 degrees and 51 degrees respectively, these values could be obtained by adding or substracting approximately 25 degrees from the latitude of this area $(36.3^{\circ}N)$ .The relationship between orientation factor and declination of sun at suitable tilt angle of 33 degrees $(s=0.9\O)$ was shown at Fig.4. 3.The thermal efficiency of solar wdter collector was shown 13.4-51. 6% on Aug. 15 (the minimum radiation recorded) and 43.8 ~537% Aug.20 (the maximum radiation recorded), and 13.8~ 46.6 and 44.3~ 49.7 were shown on each corresponding day. 4.The thermal efficiency of the collectors according to the weather condition was shown a big difference of about 10% between the day of the maximum radiation recorded and the minimum, but the differen of efficiency between the air and the water collector was at most 2 ~ 3%. 5. Even if the efficiency of the solar water collector was a little higher than the solar air collector, for drying farm products, the solar air collector was thought to be more effective because the air heated by collector could be directly used for drying them.

• Korean Journal of Veterinary Research
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• v.50 no.4
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• pp.297-302
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• 2010

This study was conducted to investigate the effects of feeding probiotics (gene modified yeast) on the growth performances in pigs. In pigs, this study investigated the effects of dietary probiotics which contained antibacterial probiotics (OR-7, bacteriocin, gene modified yeast) on growth performances and feed efficiency in pig farm. A total of 150 pigs were studied. The treatments are probiotics yeast (PY) 0.3% (basal diet + 0.3% plasmid modified probiotics), PY 0.5% (basal diet + 0.5% plasmid modified probiotics), yeast (Y) 0.3% (basal diet + 0.3% probiotics), Y 0.5% (basal diet + 0.5% probiotics) and control (basal diet). Weight gain, feed intake and feed efficiency were periodically recorded for 90 days. The treatment group trended higher weight gain, feed intake and feed efficiency than control. And, the PY group trended higher weight gain, feed intake and feed efficiency than Y group.

• Journal of the Korean Society of Tobacco Science
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• v.19 no.2
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• pp.83-91
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• 1997

The vein-necrosis strain or potato virus Y (PVY-Vff) and black shank (Phytophlhora parasitica roar. nicotianae) causes severe damage on burley tobacco(Wicotiana tabacum L.) in Korea, A new burley tobacco resistance to PVY and black shank, KB 110, was developed by Korea Ginseng and Tobacco Research Institute. It was developed from the cross of Burley 21 with TC 591 in 1990, and was backrossed to Burley 21 in the following season. TC 591 has resistance to PVY and moderate resistance to race 0 of black shank, but it is susceptible to tobacco mosaic vim (TMV). KB 110 was evaluated for its resistance to PVY, TMV and black shank in the greenhouse and at fields for preliminary and performance trials. KB 110 which has secreting glandular trichomes was resistant to PVY-VN, TW and black shank. It had an erect growth habit and two more leaves per plant than that of Burley 21, and matures two to three days later. It yielded approximately 3 percent more cured leaf than the standard cultivar Burley 21, but other plant characteristics were very similar to those of Burley 21. It had acceptable standards for chemical and physical characteristics of lured leaf on regional farm test in 1995-1997. KB 110 produced average yields of good quality tobaccos and was appeared to be resistant to PVY inwhere occurrence of the virus are severe chronic at burley growing area.

• The Plant Pathology Journal
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• v.18 no.3
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• pp.142-146
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• 2002

The effect of potassium phosphonate ($KH_2PO_3 or $K_2 HPO_3$) on the control of Phytophthora root rot of lettuce was evaluated in a liquid hydroponic culture. Phosphonate 100 ppm strongly inhibited mycelial growth of Phytophthora species in vitro but did not affect normal growth of lettuce in a greenhouse test. Application of the chemical before infection showed over 94% control value, while it was less than 35% when applied after infection. In a field trial, phosphonate 100 ppm, which was directly supplemented into the nutrient solution, satisfactorily controlled the disease as it did not develop until 28 days after transplanting and remained at less than 2% infection rate at the end of cultivation. Meanwhile, in the control plot, the disease initiated at 7 days after transplanting and developed rapidly reaching over 70% infection rate at 28 days. Population density of the causal pathogen, R drechsleri, in a heavily infested farm was 22.0-25.0 cfu/100 ml of nutrient solution. However, it decreased to 1.3-2.0 cfu/100 ml at 7 days after treatment with phosphonate 200 ppm.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.2
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• pp.153-159
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• 1998

The vein necrotic strain of Potato Virus Y (PVY - VN) and black shank (Phyto-phthora parasitica var. nicotianae) are the two major diseases causing severe damages especially in burley tobacco (N. tabacum L.) area in Korea. A new tobacco variety, KB 111, resistant to PVY and black shank disease, was developed by Korea Ginseng & Tobacco Research Institute in 1997. It is a male sterile(MS) F$_1$ hybrid of the cross between MS TC 613 and KB 108. KB 111 was compared to Burley 21 on the agronomic characteristics and disease resistances in performance tests: It possessed upright growth habit and flowered two days later than Burley 21. It was resistant to both PVY and black shank and yielded about 3% more cured leaf than Burley 21, but other characteristics are very simiar to those of Burley 21. The chemical composition and physical properties of the cured leaf of KB 111 were as much acceptable as those of Burley 21 while it produced average yield of good quality leaf and appeared to resistant to PVY and black shank disease on regional farm test in 1998.

• Journal of the Korean Solar Energy Society
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• v.29 no.2
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• pp.22-30
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• 2009

In order to clarify predictive accuracy for the wind resource predicted by running WindPRO(Ver. 2.5) which is software for wind farm design developed by EMD from Denmark, an investigation was carried out at the northeast region of Jeju island. The Hangwon, Susan and Hoichun sites of Jeju island were selected for this study. The measurement period of wind at the sites was for one year. As a result, when the sites had different energy roses, though the two Wind Statistics made by STATGEN module were used for the prediction, it was difficult to exactly predict the energy rose at a given site. On the other hand, when the two Wind Statistics were used to predict the average wind speed, the wind power density and the annual energy production, the relative error was under ${\pm}20%$ which improved more than that when using only one Wind Statistics.

• Journal of the Korean Solar Energy Society
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• v.33 no.6
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• pp.70-76
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• 2013

Recently industrial control systems have been required to ensure intelligent, high tech automation, interconnection and interoperability demands. Therefore, there is a need to redefine the structure concepts of SCADA system for wind power. Also, at this time, the integrated management system is required for the distributed development of wind farms where are needed often interoperability features and exchange information between different wind farms, wind turbines or SCADA systems. In this paper, an integrated structural concepts for SCADA system are defined. Based on this definition of an integrated SCADA system, the basic designs are analyzed on physical layer, system layer and application layer which are corresponded to wind turbine controller, the SCADA server and the SCADA client, and implement HMI. Between the implementation SCADA server and the client, their normal functions were verified at the small scale wind energy test facilities.

• Journal of Environmental Science International
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• v.31 no.11
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• pp.967-980
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• 2022

Mentha spicata, Ocimum basilium L., and Rosemarinus officinalis L. were selected as subjects for the study, and analysis of rosmarinic acid contents by HPLC analysis and the fragrance components of each herb were compared by GC-MS analysis. It was prepared and cultivated in a herb farm located in Sacheonjin-ri, Gangneung-si in 2022 (Fig. 1) before flowering, collected in the summer, stored at minus 20℃, and dried 50 g each. The analysis was requested to the NICEM analysis room of Seoul National University to obtain the test results. Through the above study, HPLC showed that the content of rosmarinic acid was 555.53 mg/Kg, which was absolute, 27.12% in rosemary for 1,8-cineol in GC-MS, and 32.44% in linalool in sweet basil. For eugenol, 23.11% in sweet basil and 19.92% in rosemary were found in α-pinene. Through this study, it was verified that spearmint, sweet basil, and rosemary contain a large amount of major ingredients that act on concentration or brain activation.

• Journal of Biosystems Engineering
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• v.35 no.1
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• pp.10-14
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• 2010

Biodiesel of 20% (BD20) and 100% (BD100), alterative fuels for tractor, were tested for its power and competitiveness in the various farm operations including plowing and rotary tilling in the paddy fields. No troubles such as engine ignition or abrupt stopping were monitored during the works of plowing, rotary tilling and travelling on the road. According to the tractor PTO test in accordance with OECD tractor PTO test codes, no significant PTO output difference was found between the three fuels. However, fuel consumption rates were different between the biodiesels and diesel fuel in the paddy works, where as biodiesel percentage increased more fuels were spent than the diesel fuel. The reason for this phenomenon seems came from density difference of the three fuels. Maximum fuel consumption difference occurred between BD100 and diesel fuel was about 10% in the plowing. More energy was spent on the rotary tilling operations than the plowing, where 35~40 % more fuel needed on rotary tilling than plowing. Of the exhaust gases, more $CO_2$ was discharged from diesel fuel than biodiesels, but more NOx from biodiesels and CO was hard to determine which fuel produce more amount.

• Journal of Life Science
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• v.19 no.9
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• pp.1304-1308
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• 2009

To investigate the infection patterns of porcine epidemic diarrhea virus (PEDV) in Korean pig farms, a total of 4,768 swine sera samples from 159 pig farms were taken twice, in June (n=82) and October (n=77) in 2007. In each farm selected for the survey, 10 samples from breeding pigs and 4 from each of the 5 age groups (30, 60, 90, 120, and 150 days) were taken, and all serum samples were tested for PEDV by the serum neutralization test. The overall seroprevalence was 62.6% (2,983/4,768), with the highest prevalence in breeding pigs (93.5%, 1,485/1,589). The prevalence showed an increasing trend with increasing age (30.8, 27.2, 44.7, 61.6, and 71.2% respectively in the 30, 60, 90, 120, and 150 days age groups) (p<0.0001 for $x^2$ trend test). The association between age and PEDV prevalence was similar in both surveys, indicating that the infection of PEDV seemed to be occurring repeatedly in the farms surveyed. This inference could also be explained by the fact that prevalence in sows was very high despite low vaccination coverage, as they are continuously exposed to PEDV in potentially infected farms for a longer period. Based on the neutralizing antibody levels in sows and growing pigs, the majority of farms (91.8%, n=146 farms) were endemically infected with PEDV, and most of pigs seemed to be intensively infected with PEDV at around early growth (41.8%) and weaning (31.5%). On the other hand, serum neutralizing antibodies were not detected in pigs older than 30 days of age in farms classified as having no PEDV infection (n=13 farms), indicating the level of maternal antibody against PEDV is decreased on a non-detectable level before the piglet is 60 days old in the field situation. The results indicated that most farms surveyed in 2007 were affected with endemic PEDV infection. Therefore, a national monitoring and control program for the endemic type PEDV infection needs further attention.