• Journal of Biosystems Engineering
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• v.30 no.6 s.113
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• pp.321-326
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• 2005

Tractor performance was analyzed using the data from 226 Korean-made and 107 imported tractors tested at the National Institute of Agricultural Engineering for the 25-year period from 1980 through 2004. The performance analysis included the specific volumetric fuel consumption (svfc), power per unit weight and traction coefficient evaluated from the viewpoint of PTO power level. No significant performance improvement has been made for the Korean-made tractors over the last 25 years. The average svfc for the maximum PTO power has increased by only $2.1\%$ from 1980 to 2004, resulting in 2.86 kW${\cdot}$h/L in 2004. The average maximum PTO and drawbar power per unit weight of ballasted tractors were 1.38 and 1.19 kW/kN in 2000-2004, indicating $14.0\%$ and $5.9\%$ decreases respectively from 1980 to 2004. The traction coefficient has increased by $23.1\%$ over the 25 years, resulting in 0.68 in the 2000-2004 period. Poor performance improvement was also observed from the imported tractors. In the 2000-2004 period, average svfc for the maximum PTO power, PTO power per unit ballasted weight, drawbar power per unit ballasted weight and traction coefficient of the imported tractors were respectively 3.0 kW${\cdot}$h/L, 1.34 kW/kN, 1.13 kW/kN and 0.68. PTO and drawbar power per unit weight were lower in imported tractors than the Korean-made tractors. Comparing the test results with those of tractors less than 37 kW tested at the Nebraska Tractor Test Laboratory from 1981 to 2002, the Korean-made tractors have exhibited better performance in terms of power per unit weight. However, poor performance in the svfc and traction coefficient was observed. The average svfc and traction coefficient of the Korean-made tractors were respectively $86.4\%$ and $83.7\%$ of the tractors tested at the NTTL over the same period.

• Magazine of the Korean Society of Agricultural Engineers
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• v.26 no.4
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• pp.37-51
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• 1984

The purpose of this study is to find out the determination method of designed duty of water in the rice fields through the comparison of the net unit duty of water at the late reduction division to heading stage with that at the planting stage. The data used for analysing this problem are the data of precipitation and gauge evaporation observed by Cheong-ju Meterological Center, the coefficient of evapotranspiration by College of Agriculture, Chung Buk University and the data of transplanting progressing in Boun area. The results obtained from this analysis are summarized as follows. 1.The occurring year of 1/10 probability value for available precipitation, gauge evaporation and mean maximum daily evapotranspiration during growing season is the year of 1977. 2.The 1/10 probability values of mean maximum evapotranspiration per day under the production rate of 1, 400kg/l0a and 1, 500kg/10a based on the weight of dry matters are 9. 2mm/day and 9. 6mm/day, respectively. 3.The net unit duty of water required in the fields that the maximum planting rate exists is more than the one in the fields that the planting rate is uniform in the planting stage. 4.The determination of net unit duty of water in the late reduction division to heading stage or the planting stage depends upon the daily evapotranspiration and percolation rate in the late reduction division to heading stage or the water depth required for planting and daily consumptive use of water after planting at the planting stage. Therefore the use of figure 5-(1) to figure 5-(6) can easily make the determination of the designed net unit duty of water out of above two kinds of net unit duty of water.

• Journal of Korean Society of Water and Wastewater
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• v.31 no.5
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• pp.447-457
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• 2017

This study derived the unit of industrial water usage reflecting the latest industry trends. Available for establishing plans such as the master plan for water supply system and analyzed changes in the basic unit by a comparison with the current basic unit values. This study analyzed 4,038 samples with a sampling error of less than 1.5 % at the 95 % confidence level after removing outliers according to a log-normal distribution. As a result, the unit of industrial water usage per site area in the whole manufacturing industry was 7.11 m3/1,000m2/d. The ten industrial categories (C10, C13, C20, C21, C22, C25, C27, C30, C32, C33) showed a similar unit value compared to before, and the four industrials categories (C11, C17, C22, C31) showed a more unit value than before. With regard to the nine industrial categories (C14, C15, C16, C18, C19, C24, C26, C28, C29), the unit value decreased. Cases that companies examined before were the same as the companies examined in this study were analyzed. The result that the changes in the unit industrial water usage were reasonable was obtained. However, in some industrial categories (C17, C14, C24, C29), the unit value was changed by a small number of companies with large-scale water use or unit value of sampling had a large deviation. It was considered necessary to survey them periodically. The unit of industrial water usage derived by the survey in this study reflects the current industrial trends in 2016. Water use in manufacturing companies has continuously changed by the development of manufacturing technologies and simplification of manufacturing processes. In order to deal with this, it is considered necessary to survey the usage of industrial water periodically from a long-term perspective.

• Korean Journal of Environment and Ecology
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• v.31 no.2
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• pp.202-219
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• 2017

The purpose of this study was to analyze the community structure of forest vegetation in Mt. Geumsusan belong to Woraksan National Park for providing basic information of ecological management. Data were collected by 41 plots from June to November in 2016 using Z-M phytosociology method, which was analyzed with vegetation types, mean importance value and coincidence method. As the results, the forest vegetation was classified into Quercus mongolica community group including Cornus controversa community, Castanea crenata community(Vegetation unit 3), Quercus variabilis community(Vegetation unit 4) and Q. mongolica community(Vegetation unit 5). C. controversa community was divided into two groups such as Ulmus davidiana var. japonica group(Vegetation unit 1) and Parthenocissus tricuspidata group(Vegetation unit 2). Mean importance percentage of vegetation unit 1 was showing Fraxinus rhynchophylla 14.9%, Morus bombycis 8.7% and Acer pictum subsp. mono 8.3%, that of unit 2 was Larix kaempferi 23.2%, C. controversa 20.1% and P. tricuspidata 6.5%, that of unit 3 was Q. mongolica 15.8%, C. crenata 13.4% and F. rhynchophylla 9.8%, that of unit 4 was Q. mongolica 26.6%, Q. variabilis 20.8% and Pinus densiflora 16.7%, that of unit 5 was Q. mongolica 48.3%, Styrax obassia 7.5%, F. rhynchophylla 5.3% in the order, respectively. Each vegetation unit was classified with dependance on environmental factors as 700m of altitude, $20^{\circ}$ of slope degree, middle slope of topography, 20% of bare rock, 30 taxa of present species, 80% of tree layer coverage rate and 20m of tree layer height. In conclusion, it was preferentially considered that development of peculiar and specific management methods with vegetation unit classified above should be needed for ecological and sustainable forest vegetation management.

• Journal of Korean Academy of Nursing
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• v.3 no.2
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• pp.45-51
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• 1973

Bacterial cultures of the transfer forceps, 4"$\times$4"mesh gauze and polluted air of nursing units of general surgery, internal medicine, gynecology and pediatrics of S.N.U.H. were carried on for S consecutive days (from 17th to 21s1 August, 1972) to investigate the degree of contamination of such instruments which were used in dressing the patients. 1. The average hospitalized patients for each nursing unit were 24 persons. 2. The frequency of dressing, and using forceps and gauze in surgical nursing unit were 25,316 and 66 times respectively. Actually the forceps were used most frequently. There was no dressing in the nursing unit of internal median. 3. Most of dressing were carried on from 11 : 00 to 13 : 59 o′clock. 4. Averagely 121.5 persons passed through each nursing unit. 549 visitors dropped in the nursing unit of gynecology in maximum, and 219 visitors in the nursing of internal medicine in minimum. The visitors rushed in from 11 : 00 to 13 : 59 o′clock to he 142.5 persons for each nursing unit in average. 5. Colony counts after the bacterial cultures of the forceps and gauze disclosed 1098.44 and 704.51 per plate respectively. 6. The degree of contamination was parallel to the duration and frequency of dressings. 7. The degree of contamination of the instruments was severest in the nursing unit of internal medicine, and !east in the nursing unit of gynecology. On the matter of gauze, the contamination was most extreme in the pediatric nursing unit. 8. There was no significant daily differences in terms of contamination throughout the week. 9. It was disclosed that empty forceps jars were less contaminated than the jars with solution of any kind. 10. Bacterial cultures of the polluted air in corridor showed 73,88 colony counts per plate.

• Journal of Life Science
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• v.14 no.3
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• pp.391-395
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• 2004

To overproduce the cyclodextrin glucanotransferase(CGTase) of Bacillus stearothermophilus NO2 in B. subtilis, the pJH-CGTl plasmid (8.14 kb) was constructed, in which the ORF of CGTase gene could be transcribed by strong constitutive promoter, P$\_$JH/. To overproduce CGTase from a recombinant B. subtilis, the effect of media on the cell growth and expression level of CGTase were investigated with various media (LB, 2${\times}$LB, 5% molasses+2% CSL, CS, LBG) in the flask culture. Among them, [5% molasses+2% CSL] medium revealed the maximum expression level of CGTase with 1.8 unit/$m\ell$ at 9 hr culture. In the batch culture on [10% molasses+5% corn steep liquor] medium the expression level of CGTase, the secretion efficiency, and plasmid stability were about 4.2 unit/$m\ell$, 90% and 90%, respectively, at 30 hr culture. The cell growth and expression level in the fermenter culture with the industrial molasses medium were increased by 2-folds over the flask culture.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.32 no.1
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• pp.7-15
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• 1996

Full scale experiment was carried out in the southern sea of Korea to compare some important factors tested in the model experiment. The results obtained can be summarized as follows ; 1. The changing aspect of mouth performance of the full scale net was almost coincided with the results obtained by the model experiment. The vertical opening(H) and the opening area(S) can be expressed as a function of the towing velocity(V) as H=48.78. $e^0.38V$(unit: m, k't) S= 1,443 .$e^-0.25V$(unit: $m^2V$, k't) 2. The changing aspect of working depth of the full scale net was almost coincided with the results obtained by the model experiment. The depth(D) can be expressed as a function of the towing velocity(V) and the warp length(L) as D=92.49.$V^1.37$(unit: m, k't, L= 150m) D= 12.07+0.32. L (unit: m, V=2k't) [)= - 7.90+0.22 . L (unit: m, V=3k't) 3. Some problems were found to operate A - type full scale net by common bottom pair trawlers. The problems can be summarized as follows; (1) Entangling of wing and square head ropes while net casting.(2) Man power needed and time spent for net hauling by common bottom trawlers increased considerably.( 3) Tearing of nettings caused by over -load of tension and entangling of net pendant while net hauling. To solve these problems, the trawlers are favorable to be equipped with variable pitch propeller and llet drum. While the net is favorable to be constructed with trifurcated net pendant in stead of quadrifurcated net pendant used at present.

• Journal of the Korean housing association
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• v.25 no.2
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• pp.27-36
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• 2014

The revision of regulations for apartment unit design, which are concerning the area calculating criteria (revised in 1998) and use of balcony (revised in 2005), considerably have increased livable space of apartment unit. This paper aims to verify its effect to apartment unit plan in the aspect of number of rooms and size of each room. For this purpose, 60 and 85 $m^2$ sized apartment unit plans in Seoul Gangnam district have been analysed by construction period, and a conclusion is drawn out as following; (1) The revison of regulations in 1998 and 2005 increased livable space of 60 and 85 $m^2$ sized apartment about 16.4~20.6 $m^2$ area. (2) Bedrooms, living room, dining room and kitchen have no change in size in nominal sense, actually, they increase their size after the fact by converting balcony to livable space. (3) Bathroom, dress room and entrance space have been considerably increased in size, which is possible for available area added in place of wall footprint according to 1998 revision.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2643-2647
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• 2013

Background: Despite anti-smoking campaigns, smoking prevalence among Thai males aged 30 or older is high, at around 50%. The purpose of this study was to determine the relationship between smoking and mortality in a rural Thai community. Materials and Methods: Subjects enrolled into the Khon Kaen cohort study between 1990 and 2001 were followed up for their vital status until $16^{th}$ March 2012. The death resource was from the Bureau of Policy and Strategy, Ministry of Interior, Thailand. A Cox proportional hazards model was used to analyse the association between smoking and death, controlling for age, education level and alcohol drinking, and confidence intervals were calculated using the floating risk method. Results: The study recruited 5,962 male subjects, of whom 1,396 died during a median 13.5 years of follow-up. Current smokers were more likely to die than never smokers after controlling for age, education level and alcohol drinking (HR, 95%CI: 1.41, 1.32-1.51), and the excess mortality was greatest for lung cancer (HR, 95%CI: 3.51, 2.65-4.66). However, there was no increased risk with increasing dose of tobacco, and no difference in risk between smokers of yamuan (hand-rolled cigarettes) and manufactured tobacco. Conclusion: Mortality from cancer, particularly lung cancer, and from all causes combined is dependent on smoking status among men in rural Thailand, but the relative risks are lower than have been reported from studies in high income countries, where the tobacco epidemic is more established.

• Parasites, Hosts and Diseases
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• v.59 no.3
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• pp.273-280
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• 2021

Biting midges (Culicoides: Ceratopogonidae) were collected using New Jersey light traps at Yongsan US Army Garrison (USAG;urban), Seoul Metropolitan city and Camp Humphreys USAG (rural), Pyeongtaek, Gyeonggi-do (province), Republic of Korea , from May-October 2010-2013 and 2015-2017, to determine species composition and seasonal distribution patterns in urban and rural habitats. A total of 9,958 female (53.85%) and 8,533 male (46.15%) Culicoides comprising 16 species were collected. Overall, the most commonly collected species was Culicoides arakawae (74.3%), followed by C. circumscriptus (16.2%), C. kibunensis (2.5%), C. nasuensis (2.2%), C. clavipalpis (1.4%), and C. pallidulus (1.3%), while the remaining 10 species accounted for <2.1% of all Culicoides spp. collected. The 2 predominant species collected were C. circumscriptus (47.4%) and C. arakawae (33.4%) at Yongsan, and C. arakawae (90.4%) and C. circumscriptus (3.9%) at Camp Humphreys. The seasonal abundance of these 2 species varied between years and between sites but on average peaked in August-September for C. arakawae and June-July for C. circumscriptus. Annual variations in abundance were observed for most species collected during this study. Unusually high proportions of male specimens were observed for most species at both sites which may be due to the use of the New Jersey trap.