• Korean Journal of Environmental Biology
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• v.32 no.4
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• pp.389-394
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• 2014

This study was conducted to find out the soil $CO_2$ emission characteristic due to rain fall pattern and intensity changes. Using Automatic Opening and Closing Chambers (AOCCs), we have measured annual soil respiration changes in Pinus koraiensis plantation at Seoul National University experimental forest in Mt. Taehwa. In addition, we have monitored heterotrophic respiration at trenching sites ($4{\times}6m$). Based on the one year data of soil respiration and heterotrophic respiration, we observed that 24% of soil respiration was derived from root respiration. During the rainy season (end of July to September), soil respiration at trenching site and trenching with rainfall interception site were measure during portable soil respiration analyzer (GMP343, Vaisala, Helsinki, Finland). Surprisingly, even after days of continuous heavy rain, soil water content did not exceed 20%. Based on this observation, we suggest that the maximum water holding capacity is about 20%, and relatively lower soil water contents during the dry season affect the vital degree of trees and soil microbe. As for soil respiration under different rain intensity, it was increased about 14.4% under 10 mm precipitation. But the high-intensity rain condition, such as more than 10 mm precipitation, caused the decrease of soil respiration up to 25.5%. Taken together, this study suggests that the pattern of soil respiration can be regulated by not only soil temperature but also due to the rain fall intensity.

• Journal of Fashion Business
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• v.9 no.4
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• pp.59-78
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• 2005

This study aims to know the deferences of hair fashion feeling group in accordance with hair styling activities, general characteristics, life styles objecting to capital area university women students and aid to hair fashion design. So the results are as belows. 1. Frequency Analysis of Categories A. Hair fashion feeling - Natural, sexy, romantic pretty, sophisticate, ethnic are 90% in total hair fashion feeling variables in sequence of frequency, so it can be said these are in vogue. B. Hair styling activities - The objections visit the hair salon once 1-2months, spend about 42,000 won a month, perform cut & wave perm to sentimental reasens & hair style changes, determine the hair style well coordinated in her image and managed easily. In her home, they manage her hair style 12 minutes a day, spend 17,000 won to buy hair aids, do hair blow dry or pin or pony tail mainly in the morning, scarcely use the hair styling aids but if use, essence or wax mainly. And the degree of interest to hair style is high. C. General Characteristics - The objections's average age is 21.1, residence is seoul kangnam 23.3%, seoul kangbook 18.4%, other capital areas 58.4%, the degree of education is university students 94.9%, graduated student 5.1%, marriage is married 96%, unmarried 2.8%, family who live with is married are mainly man & woman and living with father & mother in low in man's, unmarried are mainly live alone & nuclear family, personal expenses a month is 300,000 won in average, income of home is 4,000,000 won a month. D. Life style - The objections are not in interest of physical exercises but if are, do yoga & health, like drama & comedies program, watch TV or meet friend in leisure time, like balad & dance music, fashion magazine, meet friend in cafe or college. 2. Relationship of hair fashion feeling & other variables Using the $x^2$-test, level p<0.05, Hair styling activities(frequency of hair salon coming in and out, ordinary time representing hair style, preferred hair styling aids, the amount of hair style interest), General Characteristics(age), Life style(leisure time) variables are meaningful.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.3
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• pp.161-168
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• 2002

A behavioral investigation in deer equipped with EMG telemetry system was carried out to examine the chewing behavior pattern for efficient feeding management of Korean spotted deer(Cervus nippon). There was more frequent and irregular eating and rumination behavior pattern in deer than those in other ruminants. Time spent on eating and ruminating was 261 and 291 min., respectively. Total number of boli regurgitated was 647 times per a day and deer regurgitated an average boil of 21.6 times per a rumination period. Total rumination time was 291 min. and deer have an average rumination time of 26.9 sec. per a boli. Deer had 245.3 min. for total chewing time, 20,405 times fur number of chews, 31.5 times for number of chews per bolus, and 53.4 times for number of chews per minute during rumination period. An average regurgitation bolus an hour was lower with 15.3 numbers in the 09∼15 hours subperiod and higher with 26 numbers in the 15∼21 hours subperiod and it had been gradually trended to become to low after 15∼21 hours subperiod. An average numbers of chews a bolus at every 6 hours subperiod increased gradually according to time. A deer spent 23.3 min. on eating and 26.2 min. on ruminating per 100g ingested dry matter. Consequently, since deer have a different chewing behavioral pattern to other ruminants such as more frequent and irregular eating and ruminating patterns, small bolus and low number of chew, it is likely to needed to establishment and development efficient feeding system for deer.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.1
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• pp.49-54
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• 2000

A field experiment was carried out to determine the effects of seeding methods and rates on the growth characteristics, forage yield and nutritive value of sorghum X sudangrass hybrid (Sorghum bicolor (L.) Moench, cv. Pioneer 988) grown under application of animal manure in 1995. The application amount of animal manure were 40MT in cattle manure, 30MTha in swine and poultry manure. The methods and rates of seeding treated in this study were drill of 30kg, and broadcast of 30, 60 and 100kgha of seeding rates. The plant height was 180cm, 191cm and 204cm in cattle, swine and poultry manure, respectively. Plant height in the plot of drill was higher by about 15cm than those of broadcast plots. The dry matter(DM) yield was 7.73, 8.87 and 9.80MTha in cattle, swine and poultry manure, respectively. A significant higher forage yield was produced in the plot of drill, compared with broadcast(Pc0.05). DM yields in broadcast of 60kg and lOOkg of seeding rates were higher than that of 30kg of seeding rate of broadcast. However, no significant difference in forage yield was found between 60kg and IOOkg of seeding rates. The average DM yield was 11.16, 6.94, 8.26 and 8.83MTIha in drill(30kg), broadcast 30, 60 and 100kgIMT of seeding rates, respectively. The nutritive value of sorghum x sudangrass hybrid was very similar among treatments. The crude protein yields were 1,010kg in cattle manure, 1,180kg in swine manure, and 1,592kg in poultry manure. The protein yield was significantly high in the plot of drill. In conclusion, seeding by drill was recommended for forage production and protein yield of sorghumxsudangrass hybrid, and proper seeding rates were 30kg in drill and 60kg in broadcast. (Key words : Sorghumxsudangrass hybrid, Seeding rate, Seeding method, Forage yield, Nutritive value, Animal manure)

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.2
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• pp.129-136
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• 2007

To investigate the effect of large patch infection on oxidative stress induction, growth, $H_2O_2$ concentration and lipid peroxidation were compared between pathogen-infected and healthy (control) zoysiagrass. The sampling for leaves and roots were carried out every 2 days for a period of 6 days. Pathogen-infection increased root mortality by 30% compared to control. Dry mass was not significantly affected by pathogen-infection until day 4, but significant decreases in both leaves (-14%) and roots (-20%) were observed at day 6. The $H_2O_2$ concentration in pathogen-infected leaves rapidly increased within the first 2 days(+28%) and then slightly decreased. The increase of $H_2O_2$ in pathogen-infected roots was distinct, showing 1.7-fold higher level than control at day 6. The extent of lipid peroxidation caused by pathogen-infection continuously increased for the first 4 days. This was then stagnated until day 6. In roots, the significant increase of lipid peroxidation was observed only at day 2. These results indicate that large patch-infection induces oxidative stress, and that the oxidative stress responsive pattern was plant organ specific.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.4
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• pp.419-428
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• 2012

This study was carried out to analyze winter cereal crops for harvest time, proper drying time and haylage quality in order to investigate the possibility of the production of good quality haylage substitute for hay. As a result, in case of productivity and feed value, dry matter yield and TDN yield was increased with late harvest and crude protein and NDF, ADF was decreased (p<0.05). To make haylage for whole crop barley, oats, triticale, whole crop wheat need more than 32 hour wilting time in the milk ripe stage, yellow ripe stage need about 8~24 hour, and wilting time did not need the full ripe stage. Rye does not suitable for making haylage because of difficulty pre-wilting time. In case of fermentative quality on haylage, pH was increased with late harvest on all winter cereal crop forage. Lactic acid content was decreased with late harvest (p<0.05), and highest in the milk ripe stage. Acetic acid was also decreased with late harvest, and butyric acid was not detected. In conclusion, to harvest sooner of winter cereal crops could be an efficient way when making haylage in terms of protein content and fermentation quality. Ray can used as fresh and silage, because difficulty for pre-wilting time in Korea. Whole crop barley, oats, triticale, wheat can be used haylage when harvested yellow ripen stage and pre-wilting time for 8~24 hours.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.4
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• pp.397-404
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• 2012

This study was carried out to investigate the effects of stocking density on eating and ruminating behavior of Hanwoo steers (Bos taurus coreanae) in the finishing period. A total of 30 finishing Hanwoo steers ($631.3{\pm}11.4$ kg, 25 months old) were allocated to one of four stocking density groups comprising 1, 2, 3, and 4 steers per 32 $m^2$ pen [G1 (32 $m^2$), G2 (16 $m^2$), G3 (10.7 $m^2$) and G4 (8 $m^2$), respectively] in triplicate. Eating, rumination behaviors, as well as dry matter intake of steers were measured, and the results were subjected to analysis of variance with stocking density as the main effect. The results of eating behaviors over 48 hours are summarized as follows: Total intake was significantly (p<0.01) higher in G1, G2, and G3 compared to G4. Eating time was not different among the treatments, whereas ruminating time increased in the order of G1 > G2 > G3 > G4 (p<0.01). However, resting time and chewing time (sum of eating and ruminating) were not significantly different among the treatments. Number of boluses and number of total chews were highest in G1 (p<0.01), whereas number of chews per bolus was highest in G3 (p<0.01). Ruminating time per bolus as well as number of boluses per minute was not significantly different among the treatments. Number of defecations was higher in G1 and G2 animals compared to G3 and G4 animals (p<0.01). However, stocking density had no effect on drinking or urination. In conclusion, increasing stocking density (i.e. G4) per pen decreased voluntary intake, ruminating time, and total chewing number in the finishing period of Hanwoo steers. However, care must be taken in discussing stocking density in the present study as the space allowance per animal was satisfactory to meet the current animal welfare regulation in Korea and in Europe, although the beef production system in Korea is more intensive than in Europe.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.2
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• pp.111-116
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• 2013

This experiment was carried out to select a resistant corn variety for rice black-streaked dwarf virus (RBSDV) disease in a RBSDV prevalent area (Gochang of Jeollabukdo) from 2006 to 2008. Ten corn varieties for silage preparation were cultivated with first cropping and second cropping system in an RBSDV field, and were tested outbreak rates of RBSDV and dry matter (DM) yield of forage. The outbreak rates of RBSDV were significantly different between corn varieties. Therefore, the resistance degree of corn varieties for RBSDV were divided into 4 groups; very resistant ('Kwangpeyongok' and 'Kwanganok'), resistant ('P3156' and 'P3394'), mildly resistant ('Cheonganok' and 'P32P75') and susceptible ('Suwon19', 'DK697' and 'GW6959') groups respectively. DM yield of forage in RBSDV fields exhibited comparatively significant differences between varieties (p<0.05). DM yield of resistant varieties ('Kwangpeyongok', 'Kwanganok', 'P3156' and 'P3394'), were higher (14~26%) than those of susceptible varieties ('Suwon 19', 'DK697' and 'GW6959'). Therefore, resistant varieties were recommended for increasing forage productivity in field of RBSDV prevalent areas.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.1
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• pp.92-99
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• 2017

This experiment was carried out to compare the growth characteristics and productivity between sudangrass and sorghum-sudangrass hybrid under the same cultivation condition in Cheonan and Kimje of Korea from 2010 to 2011. Sudangrass hybrids(Choice, Sunstar and Piper) and sorghum-sudangrass hybrids(SX-17, Jumbo and Revolution) were planted $5^{th}$ May in Cheonan and $7^{th}$ May in Kimje. Heading date of sudangrass hybrids was $12^{th}$ July which was about 2 week fast more than that of sorghum-sudangrass hybrids. Stem diameter of sudangrass hybrids was about 6mm which was about 5 mm smaller than that of sorghum-sudangrass hybrids. Disease resistance of sudangrass hybrid, "Choice" was similar to that of sorghum-sudangrass hybrids. Dry matter yield of "Choice" was 15ton/ha which was 10% less than that for sorghum-sudangrass hybrids(SX-17). Feed value of "Choice" was similar or slightly lower than that of sorghum-sudangrass. For increasing the productivity in forage cropping systems all around year, sudangrass hybrid is recommended for prolong by the middle ten day of May in the harvesting time of italian ryegrass.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.1
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• pp.44-49
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• 2017

This experiment was carried out to study the effect of rice black-streaked dwarf virus(RBSDV) infection rate on forage productivity of corn varieties in Cheonan of chungcheongnamdo from 2006 to 2008. Forage corn varieties of 10 were cultivated with first cropping(seeding in the last ten days of April) and second cropping(seeding in the last ten days of May) system in field and tested the infection rates of RBSDV and productivity of forage. The Infection rate of RBSDV was significant difference between corn varieties in middle district of Korea. Resistant corn varieties for RBSDV were 'Kwanganok', 'P3156', 'Kwangpeyongok' and 'P3394' but susceptible varieties were 'Suwon19', 'DK697', 'GW6959' and NC+7117. Dry matter(DM) yield of forage corn according with infection rates of RBSDV in field was significant difference between varieties(p<0.05). DM yield of susceptible varieties, 'Suwon 19', 'DK697' and 'GW6959' was lower about 20% than that of resistant varieties, 'Kwangpeyongok' and 'P3156'. For increasing the productivity of forage corn, recommend of resistant varieties for RBSDV and control of seeding time are very important in middle district of Korea.