• Journal of The Korean Society of Grassland and Forage Science
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• v.9 no.2
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• pp.96-102
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• 1989

This field experiment was conducted to determine the effect of grazing and cutting management on the forage production and botanical composition at different legumes sown swards of the experimental field of Livestock Experiment Station. in Suweon, from Aug. 1985 to Oct. 1988. The results obtained are as follows: 1. Dry matter yield of cutting management (1213.0 kg/lOa) was higher by 19% than that of grazing management (1016.8 kg/lOa). Yield of pasture mixtures including alfalfa both cutting and grazing were higher than those including ladino clover and red clover. Yield under grazing was inferior to cutting in the first year but superior in the second year. 2. Seasonal dry matter production under grazing showed 5 1% in spring, 33% in summer and 16% in autumn, but under cutting showed 46% in spring, 42% in summer and 12% in autumn. 3. Daily dry matter production per 10a under grazing is decreased 5.9 kg in spring, 5.5 kg in summer and 3.7 kg in autumn. But under cutting is decreased 8.7 kg in summer, 6.6 kg in spring and 3.4 kg in autumn. 4. Botanical compositions of mixtures swards involving ladino clover and red clover were not influenced by method of defoliation. But mixtures swards including alfalfa were highly influenced by method of defoliation. Alfalfa ratio at the time of final utilization under grazing was about 30%, but under cutting was about 70-80%.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.1
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• pp.121-132
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• 2011

Removal rates of $NO_3$-N and TN in the free-water surface wetland system during winter; December, January, February and March, spring and fall; April, May, October and November, and summer; Jun, July, August and September were investigated. The system was established on floodplain in the downstream reach of the Gwangju Stream in 2008. It measures 50 meters in length and 5.5 meters in width. Iris pseudacorus L. grown in pots for about two years were planted in the system. The water stream was funneled in by gravity and its effluent was discharged back in. Volumes and water quality of inflow and outflow were analyzed from December 2008 to November 2010. The inflow was averaged approximately 350 $m^3/day$ and hydraulic residence time was about 3 hours. Average influent and effluent $NO_3$-N concentration was 3.75 and 3.35 mg/L, respectively and $NO_3$-N retention was amounted to 10.6%. Influent and effluent TN concentration were averaged 4.93 and 4.30 mg/L, respectively and TN abatement reached to 12.9%. One-way ANOVA statistics claimed that the average removal rates of $NO_3$-N and TN during winter, spring and fall, and summer were not always the same (p<0.001). The t-Tests of three pairs among $NO_3$-N removal rates of winter, spring and fall, and summer illustrated that the removal rates of winter ($5.04{\pm}1.94$), spring and fall ($10.53{\pm}2.24$), and summer ($18.61{\pm}2.26$) were significantly different each others (p<0.001). Among TN removal rates, the three pairs of t-Tests of three seasons showed that the removal rates of winter ($5.21{\pm}2.51$), spring and fall ($11.71{\pm}3.12$), and summer ($21.53{\pm}4.86$) were significantly different from each others (p<0.001).

• Journal of The Korean Society of Grassland and Forage Science
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• v.10 no.2
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• pp.89-95
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• 1990

This experiment was carried out to determine the effects of nitrogen(N) fertilizer levels (0, 120, 240 and 360kg $ha^{-1}Y^{-1}$ Y-') on seasonal grass growth, dry matter (DM) yield and botanical composition in pasture under shade condition. Investigation date was on 7 , 14, 21, 28 and 35 days after harvesting in spring (May), summer (July) and autumn (Sept.), 1988, respectively. Shade degree was controlled artificially ca. 45-50%, and each annual level of N was distributed 5 times equally. Grass growth and DM productivity were most vigorous in spring. Higher DM yield was produced with N 240 kg spring, and Nl2Okg in summer and autumn. Higher significant relationships, in spring, were found between grass height and DM, and N level and DM yield. However, low relationships were observed between those in summer and autumn. In botanical composition, grass coverage was decreased in summer and autumn, and bareland was increased, especially in higher N plots. Based on the results, it is suggested that 200kg $ha^{-1}$ of N in this experiment is more effective for forage production and pasture persistence. Also a littie more amount of N (50-70kg $time^{-1}$) in spring, and low level of N (20-30kg $time^{-1}$) in summer and autumn may be desirable.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.4
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• pp.586-597
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• 2008

The purpose of this study is to find out the relationship between the personal color types and personality types and analyze the differences in color preference according to the personal color types and personality types. This study was conducted by using questionnaire method and drape diagnosis method in parallel. The results are as follows. First, in case of introversion (I), the summer type took the most and spring, fall, and winter type followed respectively. Also in the case of extroversion (E), the summer type took the most and spring, fall, and winter type followed respectively. Second, the spring type preferred yellow, the summer type, blue, the fall type, brown, and winter type, blue the most. For the preference of the tone of color, all 4 types preferred the pastel tones the most. For the lipstick colors, the spring and summer type preferred the pink color, the fall type, orange and winter type, red the most. For eye shadows, the spring type preferred orange, summer type, blue, fall type, orange and winter type, pink. For nail colors, all 4 types preferred pink the most. Third, the most preferred color for introversion (I) was red group. In contrast, the most preferred color for extroversion (E) was yellow group. In the tone of preferred colors, both introversion and extroversion preferred the pastel tones the most. In lipstick colors, eye shadow colors, and nail colors, both introversion and extroversion preferred the pink group colors the most.

• Korean Journal of Veterinary Service
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• v.20 no.3
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• pp.261-279
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• 1997

The study for a effect of monitoring on bovine mastitis was conduced for improvement of raw milk from Jan. to Dec. in 1996. Sampling the milk of 367 cows(1, 406 quarters) from 5 herds in Inchon and were carried out California mastitis test(CMT), somatic cell count(SCC), isolation of pathogens and antibiotic sensitivity tests. The results were summarized as follows, 1. The number of bovine mastitis was 177 cows(48.2%) and 371 quarters(26.4%) : clinical mastitis : 25 cows(6.8%), 32 quarters(2.3%) and subclinicsl mastitis : 152 cows(41.4% ), 339 quarters(24.1%). Incidence rate of mastitis by season were Summer 52.0%, Fall and Winter 48% and Spring 41%. Incidence rate of mastitis by quarters were Summer 30%, Fall 28%, Winter 25% and Spring 21%, respectively. 2. In the distribution of CMT degree by quarter, CMT positive(CMT$\pm$) of 1, 406 quarters milk were 50.1% (704 quarters). The ratio of CMT positivity by quarter were left front quarter 55.8%, right front quarter 48.9%, right hind quarter 48.6% and left hind quarter 47% The ratio of CMT positivity by season were Summer 54.1%, Fall 49.7%, Spring 48.5% and Winter 48% 3. The highest mean SCC by season among 5 herds was "A" herd. Mean SCC (cell/ml) of A herd were Summer 2, 032, 000cells/ml, Fall 1, 109, 000cells/ml, Winter 782, 000cells/ml and Spring 577, 000cells/ml. The lowest mean SCC by season among 5 herds was "E" herds. Mean SCC of E herd were Summer 1, 064, 000cells/ml, Spring 795, 000cells/m1, Fall 429, 000cells/ml and Winter 400, 000cells/ml. Mean SCC of the other herds by season were little difference. 4. The milk samples of "A" herd were collected from 10 cows. In 3 seasons, mean SCC of No. 2 and 3 cows were than 1, 000, 000cells/ml. In 1 season, mean SCC of No. 6, 7 and 8 cows were than 1, 000, 000cells/ml. The more than mean SCC 1, 000, 000cells/ml of cows by season were distributed Summer 4 cows, Winter 3 cows, Spring and Fall 1 cow respectively. The milk samples of "B" herd were collected from 14 cows. In 3 seasons, mean SCC of No. 1 cow was more than 1, 000, 000cells/ml. In 2 seasons, mean SCC of No. 5, 9 and 14 cows were more than 1, 000, 000cells/ml. In 1 season, No. 3, 6 and 7 cows were more than 1, 000, 000cells/ml. The more than mean SCC 1, 000, 000cells/ml of cows by season were distributed Fall and Winter 4 cows respectively, Summer 3 cows and Spring 1 cow. The milk samples of "C" herd were collected from 18 cows. In 2 seasons, mean SCC of No. 16 cow was more than 1, 000, 000cells/ml. In 1 season, mean SCC of No. 1, 2, 6, 7, 13, 15 and 18 cows were more than 1, 000, 000cells/ml respectively. The more than mean SCC 1, 000, 000cells/ml of cows by season were distributed Summer 5 cows, Fall 3 cows, Spring 2 cows and Winter 1 COW. The milk sampes of "D" herd were collected 24 cows. In 3 season, mean SCC of No. 14 cow was more than 1, 000, 000cells/ml. In 2 seasons, mean SCC of No. 14 and 18 cows were more than 1, 000, 000cells/ml. In 1 season, mean SCC of No. 1, 2, 3, 8, 12, 17, 19, 20 and 21 cows were more than 1, 000, 000cells/ml. The more than mean SCC 1, 000, 000cells/ml of cows were distributed Fall 15 cows, Spring and Winter 4 cows respectively and Summer 3 cows. The milk samples of "E" herd were collected from 27 cows. In 2 seasons, mean SCC of No. 6, 7 and 21 cows were more than 1, 000, 000cells/ml. In 1 season, mean SCC of No. 2, 4, 7, 11, 14, 16 and 23 cows were more than 1, 000, 000cells/ml. The more than mean SCC 1, 000, 000cells/ml of cows were distributed Spring and Fall 5 cows respectively, Summer and Winter 2 cows, respectively. 5. The rate of isolated pathogenic microorganisms from bovine mastitis were summarized as follows : Staphylococcus sp 168 strains(45.8%), Streptococcus sp 82 strains(22.3%), Gram(-) sp 45 strains(12.3%), Gram(＋) sp 51 strains and the other sp 21 strains(5.7%). 6. The highest of antibiotic sensitivity test of each microorganism was summarized as follows : Staphyolcoccus sp - cephalosporin 76%, gentamicin 55%, Streptococcus sp - ampicillin 61%, cephalosporin 63%, Gram(-) sp - gentamicin 58%, Gram(＋) sp - cephalosporin 63%, The other sp - cephalosporin 90%. Microorganisms showed the highest sensitivity(68%) to cephalospsorin. Microorganisms showed the highest sensitivity(68%) to cephalospsorin.

• Journal of Environmental Health Sciences
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• v.22 no.2
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• pp.90-95
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• 1996

This study was performed to calculate the degration rate coefficient, operating parameters to meet the effluent standards, and the temperature adjustment coefficients to each parameter of pollution by seasonal variation of concentration and temperature of influent in livestock wastewater treatment by sequencing batch reactor process in field scale. The followings are the conclusions that were derived from this study. 1. In the field, temperature of livestock wastewater in reactor was 20.3$\circ$C in summer and 6.0$\circ$C in winter. The ratio of BOD:TKN: T-P in influent was 100:80:7. BOD loadings in winter and spring were 0.26 and 0.43 kg $BOD/m^3$ day, respectively. Those in summer and fall were 0.25 and 0.13 kg $BOD/m^3$ day, respectively. 2. The degradation rate coefficient for TKN was larger in summer and fall in which temperature was high than that in which temperature was high than that in winter and spring in which concentration was high. On the contrary, the phosphorus uptake rate was larger in winter and spring than that in summer and fall. 3. The hydraulic retention time in winter and spring was longer than that in summer and fall. Especially, in order to meet the standard for TKN of 120 mg/l in winter in which temperature of wastewater was 6.0$\circ$C, as the MLSS concentration was increased from 4, 000 to 7, 000 mg/l, the hydraulic retention time was increased from 212 to 121 hours. But, in order to shorten that less than 121 hours for the economical wastewater treatment, countermeasure to increase temperature of wastewater in the reactor should be considered. 4. the temperature adjustment coefficients for BOD, $COD_{Mn}$, TKN and T-P were 1.0241, 1.0225, 1.0541 and 1.0495, respectively. Namely, the treatment of TKN was most sensitively affected by temperature. For the purpose of the effective removal of nitrogen and phosphorus which are sensitive to temperature, it is necessary to keep the temperature of livestock wastewater more than 20$\circ$C which is the temperature of it in summer.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.2
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• pp.104-110
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• 1992

This experiment was carried out to determine the effects of nitrogen(N) fertilization levels(0. 120, 240 and 360 kg/ha/y) on seasonal nitrate nitrogen($NO_3$-N) concentration and water soluble carbohydrate (WSC) content of grasses grown under shading condition. The plants were sampled on 7. 14, 21, 28 and 35 days after harvesting in spring(May), summer(July) and autumn(September), 1988. respectively. Shading degree was controlled artificially ca. 45-50%, and each annual level of N was distributed 5 times equally. The $NO_3$-N concentration of grasses was very low(0.064 %) in spring, high in summer(O.l98 %) and autumn(0.234%), and NO,-N was slightly decreased with growing of grasses. Also the NO,-N concentration of grasses was increased significantly with increasing level of N. In spring, the $NO_3$-N of grasses was very safety(less than 0.1 %), regardless of plant height and N level. In summer and autumn, however, plant heights of below 40 cm(summer) and 44 cm(autumn), and N levels of over 210 kg(summer) and 140 kg(autumn) were over toxic level to animals, respectively. The WSC content of grasses was slightly decreased with grass growth. and significantly decreased with high level of N. From the above results, it is suggested that 200 kg/ha of N in this experiment is effective for forage quality. Also a little more amount of N(50-70kgltimes) in spring. and low level of N(20-30 kgltimes) in summer and autumn season may be desirable on woodland posture.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.60 no.1
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• pp.37-46
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• 2024

This study was conducted to provide the basic information on environment effects on appearance of ichthyoplankton in the Yeongsan River Estuary in Spring and Summer from 2018 to 2020. Data were obtain from the database of 'Coastal Ecosystem' in "National Survey of Marine Ecosystem." Among the abundance ichthyoplankton species, the Gobiidae spp. dominated, accounting for 85% of the total abundances with the secondary dominant species being the Parablennius yatabei, representing 3% of the abundances. Cluster analysis results revealed a composition differentiated between spring and summer. The Yeongsan River Estuary is known to be significantly influenced by the opening and closing of estuarine gates. In this study, the fluctuation in the number of occurrence groups and abundance among the years and season is attributed to the phenomenon of high water temperature period and the freshwater discharge.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.2
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• pp.103-112
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• 2000

Elemental carbon(EC) and organic carbon(OC) in fine particles (PM2.5) were collected from October 1995 through August 1996 in the Chongju area. The annual mean concentrations of EC and OC were 4.44 and 4.99 $\mu\textrm{g}$/m3 respectively. EC showed seasonal variation (p<0.01) The magnitude of the seasonal mean EC concen-tration progresses in the following manner : fall>winter>spring>summer. However OC was not statistically seasonal difference(p=0.20) The annual average OC/EC ratio was 1.12 suggesting that organic carbon measured may by emitted directly in particulate form(primary aerosol) The contribution of EC to PM2.5 mass follows a general pattern in which fall(14.6%) > winter (9.8%) >spring(7.8%) =summer(7.8%) and the contribution of OC to the PM2.5 mass varies in order fall(13.8%) >winter(11.3%) >spring(10.5%) >summer (9.4%) Total carbona-ceous particles(EC and OC) accounted for 17-28% of the PM2.5 mass.

• The Korean Journal of Ecology
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• v.18 no.4
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• pp.471-481
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• 1995

The weed population dynamics as affected by contrasting conventional tillege (CT) and no-tillage (NT) practices with a minimum herbicide application was studied in Athens, Georgia, U.S.A. Common chickweed (Stellaria media) was the most common spring weed while johnsongrass (Sorghum halepense), sicklepod (Cassia obtusifolia), and pigweed (Amaranthus retroflexus) accounted for 89∼97％ of net production during summers of 1983 and 1984. Total weed production in summer of 1984 was 2∼5 times greater than that of 1983. Weed production was greater in NT plots than in CT plots in summer of 1983, but reverse was the case in summer of 1984. In spring, net production in NT plots was greater than that in CT plots, especially, in 1985. Species diversity was consistently higher in NT plots, but in the wet summer of 1984 the pattern was different, with higher diversity in CT plots. Weed species diversity was higher in the spring rye crop than in the summer grain sorghum crop. The larger but less diverse weed populations in summer of 1984 indicated that these populations experienced competitive exclusion. Under the favorable summer moisture conditions the three dominant species grew so vigorously and quickly as to exclude many less common species that were able to survive under the drier conditions in 1983. The three dominant species not only excluded other weeds in 1984 but also greatly reduced crop production. The perennial johnsongrass was equally successful, or even more so, in CT plots as in NT plots. Plowing did not kill johnsongrass rhizomes but tended to break them up, thus increasing the number of individual plants that appear after the plowing. It means that johnsongrass was not controlled by the plowing. In summer of 1983, a moderate amount of weedy growth was maintained with a minimum amount of gerbicide application in NT and CT plots. It is possible that a small mixed weed population would be beneficial by providing cover for predatory and parasitic arthropods, and by reducing soil temperature and moisture losses.