• 환경위생공학
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• 제16권3호
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• pp.42-53
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• 2001

This study were conducted to estimate property of nitrogen dioxide concentration at industrial areas in Korea. The nitrogen dioxide concentrations were measured for 50 dwellings at Ulsan and Yeochon, respectively using the nitrogen dioxide filter badge forming the passive sampler from summer time 1998 to winter time 1999. The major results obtained from this study were as follows: 1. The mean indoor, outdoor, and personal concentrations of nitrogen dioxide during summer time 1998 in Ulsan were 28.9 ppb, 24.8 ppb, 24.8 pub, respectively. 2. The mean indoor, outdoor, and personal concentrations of nitrogen dioxide during winter time 1999 in Yeochon were 11.4 ppb, 12.5 ppb, 15.5 ppb, respectively. 3. The mean concentration of nitrogen dioxide during winter time 1998 were higher than the corresponding levels during summer time 1997 in Ulsan. 4. The mean concentration of nitrogen dioxide in Ulsan were in general higher than the corresponding levels in Yeochon. 5. This results in slightly positive correlation among indoor, outdoor, and personal nitrogen dioxide concentrations for summer time in Ulsan, then it statistical significance is showed(p <.05). These results suggest that nitrogen dioxide concentrations in industrial areas seem to be affected by traffic density and conditions of industrialization.

• Journal of the Korean Wood Science and Technology
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• 제25권1호
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• pp.28-36
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• 1997

Several thick board and dimension lumbers of Japanese larch(Larix leptolepis), Dahurian larch(Larix gmelini) and radiata pine(Pinus radiata) air-dried in four different seasons to compare air-drying process. Patterns of air-drying curves were influenced by climatological conditions and limber thickness. The initial drying rates of summer were the highest, followed those of fall, spring and winter. The drying times to equilibrium moisture contents for four seasons were nearly the same except for winter. However, the drying time for winter required twice more time than the other seasons. The drying time of dimension lumbers required 1.3 times more than boards. The final moisture contents were lowest during spring, highest during winter and similar between summer and fall.

• 한국초지조사료학회지
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• 제7권1호
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• pp.18-24
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• 1987

This experiment was carried out to investigate the effects of the final cutting time and cutting height on the winter survival, regrowth, and carbohydrate reserves in stubble, and early spring yield of orchardgrass-dominated pasture before and after the winter season. The experiment was conducted at the experimental field of the Livestock Experiment Station, in Suwon, from October 1985 to early 1986. The results obtained are summarized as follows: 1. Regrowth of plant after the final cut increased significantly (P<0.05) with plot of the early cutting time (Oct. 10) and high cutting height at the final. For winter survival, cut plant should regrow over 15cm in plant height. Therefore limit cutting time and cutting height were forced to be on Oct. 25 and at 6-9cm, respectively. 2. Total water soluble carbohydrate (TSC) content in stubble after the final cut was not significantly changed by different cutting time and cutting height. 3. The percentage of dead plant after wintering was found to be high with plot of the late cutting time and low cutting height at the final cut (P<0.05). And the correlation between the percentage of dead plant after wintering and final plant height before wintering was significantly negathe (r = -0.728**). 4. Fresh and DM yield at the early spring after wintering were increased in the plot of the early cutting time and high cutting height (P<0.05) at the final cut. And significantly positive correlation was observed between the early spring yield and final plant height before wintering (r = 0.720**).

• 대한방사선기술학회지:방사선기술과학
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• 제1권1호
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• pp.37-43
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• 1978

This Study was conducted, during the period of 8-16th, August in 1977 and 27th, January through 2, Feburury in 1978, to measure laking off and on time for patient's clothes at the radiologic department in general hospitals. The study dealt with three general hospitals which were classified into groups by ownerships; two university hospitals, one private hospitals. The scope of the study was limited to measurement's of taking off and on time except taking a radiograph. The results were summarized as follows: [1] In Summer, the average taking off ana on tine for male was 3 minutes and 7 seconds and 3 minutes and 43 seconds for female. The latter was longer than that for the former. [2] In Winter, the mean taking off and on time for male was 3 minutes 42 seconds, 4 minutes 17 seconds for female. [3] In this respect, the average taking off and on time for female was longer than that for male and that for winter was expended that for summer. [4] In Summer, regardless of age group and sex, the average taking off and on time for taking a radiograph was 3 minutes 25 seconds, and 3 minuteds 59 seconds in Winter. [5] Regardless of season, sen, and age, the mean time expended to take off and on for taking a radiograph was 3 minutes 43 seconds.

• 한국토양비료학회지
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• 제46권3호
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• pp.187-192
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• 2013

This study was carried out to investigate the incorporation effect of green manure crops (GMC) such as the hairy vetch on improvement of soil environment in reclaimed land during silage corn cultivation over the past two years. Plots consisted of conventional fertilization (CF) and incorporation of GMC were divided by addition rate of nitrogen fertilizer (100 kg $ha^{-1}$) with 30 - 100% of non nitrogen fertilization (NNF). Soil physico-chemical properties and growth and yield potential of silage corn were examined. The tested soils showed strong alkali and saline properties with low contents of organic matter and available phosphate while contents of exchangeable sodium and magnesium were high. Soil salinity increased during cultivation of summer crop. However, corn was not affected by salt content. The fresh weight of GMC at incorporation time was 18,345 kg $ha^{-1}$. Content of total nitrogen was 3.09% and the C/N ratio was 12.8 at incorporation time. Fresh and dry matter yield of silage corn were higher in the order of N30% reduction, CF, N50% reduction, N70% reduction, N100% reduction and NNF. Fresh and dry matter yield potential of silage corn for N30% reduction were comparable to those of CF. Bulk density of the soil decreased with incorporation of GMC, while porosity was increased. The soil pH decreased while content of exchangeable calcium, available phosphate, and organic matter increased. Also contents of exchangeable sodium and potassium decreased with incorporation of GMC. The data indicate that incorporation of hairy vetch can improve soil physical and chemical properties and reduce nitrogen fertilizer application especially for alkali saline reclaimed soil such as Saemangeum reclaimed land.

• 한국농공학회지
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• 제41권4호
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• pp.37-46
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• 1999

Field experimnet of constructed wetland for rural wastewater treatment was performed from July 1998 to April 1999 including winter to examine the seasonal effect on the wetland performance. The system worked without freezing even under $-10^{\circ}C$ of air temperature as long as watewater was flowing. BOD removal rates varied in similar pattern as the air temperature, and winter performance was relatively lower than that in the growing season. However, removing performance during winter was still significant, and BOD removal rates were almost the the same as in the growing season. SS removal rate was relativelyless affected by temmperature, but lower decay rate during the winter can result in accumulation of the SS in the system, which releases constituents in the next spring and can affect whole system performance. The winter removal rates of nutrients like T-N and T-P were decreased about half compared to the growing season and low temperature. To maintain stabilized wetland performanced including winter time, supplying minimum heating for plants could be an alternative in field application. Experimental data was compared with NADB(North Americal Wetlands for Water Quality treatment database), and general performance of the system was within the reasonable range. The pollutant loading and effluent concentration of the experimented system were in high margin. Base on the experiment and databases, the required effluent water quality could be achieved if loading rate adjusted as ilulstrated in the database.

• The Korean Journal of Physiology
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• 제3권1호
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• pp.29-32
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• 1969

Skinfold thickness measurement and total body fat calculation were made in summer (July) and winter (December or January) On 70 medical students (age: 20 yr),8 national team basketball players (age: 20 yr), and 9 middle-age men. Skinfold thickness measurements were made on 4 sites, namely, back, arm, waist and abdomen. The mean skinfold thickness (mm) of the 4 sites was substituted into the following formulae. For adult of 20 years old: % Fat=0.911x+8.1, and for middle-aged men % Fat=1.199x+1.41. In young medical students and ball players body weight decreased, mean skinfold thickness increased in winter season. As a result total body fat .(% body weight) increased in winter In middle-aged men both body weight and mean skinfold thickness increased in winter and resulted in an increase in the total body fat. The detailed data are as follows: 1. In medical students summer: winter values were: body weight, 59.7 :58.9 kg; mean skinfold thickness, 7.85 : 8.12 mm; and total body fat, 15.0 : 15.5% body weight (P<.30). 2. In national team basketball players summer: winter values were: body weight, 73.5 : 69.1 kg; mean skinfold thickness, 7.2 : 7.5 mm; total body fat, 11.6 : 12.1% (P:NS). 3. In middle-aged men summer vs winter values were: body weight, 61.5 : 63.0 kg; mean skinfold thickness, 10.3 : 11.8 mm; total body fat, 17.2 : 18.0% (P:NS). 4. Skinfold thickness on back showed no seasonal variation and on abdomen the thickness increased in winter. 5. It was concluded that the predominant factor in increasing total body fat in winter is the decrease in body exercise in the winter time.

• 한국작물학회지
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• 제58권4호
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• pp.362-366
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• 2013

이 연구는 조제방법에 따른 수확시기별 청보리의 사료가치 및 발효품질을 평가하기 위하여 실시하였다. 그 결과, 청보리 원재료의 사료가치는 수확시기가 늦어짐에 따라 조단백질, NDF와 ADF 함량은 감소하고, TDN 함량은 증가하였다(P<0.05). 이러한 수확시기별 사료가치의 변화는 사일리지에서도 제조 전과 같은 경향이었으며, 사일리지 제조 전후를 비교하여 볼 때, 조단백질과 섬유소 함량이 다소 증가되는 경향을 보였다. 조제방법별로 볼 때 베일과 초퍼에 따른 사료가치의 차이는 보이지 않았다. 사일리지의 pH는 모든 처리구에서 수확시기가 늦어질수록 높아지는 경향을 보였고, 유기산 함량은 사일리지 조제방법에 관계없이 수확시기가 늦어질수록 줄어드는 경향이었으며(P<0.05), 조제방법별로 볼 때 품종에 관계없이 일반수확보다 초퍼에서 젖산함량이 약 23%정도 증가하는 경향이었다(P<0.05). 이상의 결과를 종합하여 볼 때, 청보리는 황숙기에 수확하는 것이 유리하며, 베일보다는 초퍼로 사일리지를 제조하는 것이 발효품질을 향상시킬 수 있는 방법이라고 사료된다.

• 한국식품조리과학회지
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• 제14권4호
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• pp.367-374
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• 1998

The purpose of this study was to evaluate the microbiological quality of, and to assure the hygienic safety of, the kimbap production in the university foodservice facilities in accordance with the HACCP (Hazard Analysis Critical Control Point) Program. The time-temperature relationship and the microbiological quality (specifically, total plate count and coliform bacteria count) were assessed to find the critical control point (CCP) during each of the production phases. The average of the daily longest duration time of the kimbap at the facilities was 23.4 hours in summer, while 29.6 hours in winter. In the purchasing phase of the raw materials, the microbiological quality of laver, fish paste, carrot and cucumber in summer was not at an acceptable level according to the standard set by the Natick research center, especially the number of TPC and the coliform level of laver was higher than the threshold level. In the refrigerator storage phase, the temperature of the carrot was 7.4$^{\circ}C$. This temperature is far exceeding the standard so that the microbiological counts was increased by the 2 log cycle during the average storage time of 17 hours or more. In the preparation phase, the temperature of the blanching is too low compared to the standard. In the holding phase before serving, its time-temperature relationship was out of the FDA food code standard both in winter and summer. In the sewing phase, the number of microbiological count was higher than the threshold level in summer while that in winter was up to standard. According to the Harrigan and McCance standard, the number of microbiological count of the utensils was higher than the threshold level in summer while that in winter was up to standard.

• 한국초지조사료학회지
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• 제33권4호
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• pp.234-239
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• 2013

This study investigated the effects of drying methods and drying time on the changes in anthocyanin content in colored barley. Colored barley cultivar Boanchalbori was harvested at a time when the anthocyanin content was the most and dried in afield. The harvested barley was then treated by two methods, sun drying and shade drying, for 4, 8, 24, and 32 h. The moisture content of the sun-dried barley decreased slightly faster than shade-dried samples, but the difference was not statistically significant. Chemical analysis indicated that the samples dried under shaded conditions had slightly higher crude fiber and lower nitrogen free extract, but the difference was not statistically significant. There was no difference in the total digestible nutrients between the two methods. In the case of sun-dried barley, the anthocyanin content decreased compared to the control and shade-dried samples after drying for 4 h (p < 0.05), was maintained at a constant level at 24 h, and then decreased at 32 h. In case of shade-dried barley, the anthocyanin content decreased gradually with the drying time, and a significant decrease was found at 24 h of drying (p<0.05) as compared to the control. The shade-dried method was more successful in reducing anthocyanin loss than the sun-dried method (p<0.05). There was a slight decrease in 1,1-Diphenyl-2-Picrylhydrazyl radical scavenging with drying time in the shade-dried method, and a significant decrease after 4 h with the sun-dried method. These results showed that covering with a two-layer awning was advantageous to dry colored barley in the field conditions.