• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.5
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• pp.548-555
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• 1995

This study was aimed to provide understanding on the eco-physiological response of barley tillers as affected by sowing method. Yield and yield contribution rates of tillers were investigated with the data of field experiments in the Honam Crops Experiment Station of Iri, Korea from October 1986 to July 1987. Narrow-seeding (each row placement 40cm$\times$seeding width of each row 18cm), drill-seeding (20cm$\times$5cm) and broadcasting on wide ridge (each ridge placement 120cm$\times$ridge width 90cm) were applied to examine the effects of various sowing methods. Primary tillers such as mainstem, 1 and 2 produced ears in all treatments, but the ear from a secondary tiller of 11 was observed only in broadcasting on wide ridge. Drill-seeding was the highest in number of spikelet, grain and plump grain per ear, while narrow-seeding being the lowest. The plump grain yield per square meter was 679.8g in narrow-seeding, while drill-seeding and broadcasting produced more than narrow seeding by 28.7% and 16.8% respectively. The actual yields per l0a for sowing methods showed a similar pattern to plump grain yield per square meter in which the yield was 567.6kg by narrow-seeding and the increments of drill-seeding and broadcasting were 30.6% and 15.4%, respectively.

• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.138-143
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• 2011

BACKGROUND: This study was conducted to investigate growth and yield of organically grown rice under a typhoon during a fall. The treatments included NPK chemical fertilizer, compost, oilcake, oilcake 2X, hairyvetch, and vetch+rye. METHODS AND RESULTS: Nutrient applications were made at rates equivalent to approximately 0.9 kg of actual N per acre. Oilcake and hairyvetch treatments had the lowest C:N ratio, but compost had the highest C:N ratio of 34:1. Rice treated by organic nutrient sources had great growth and development at the beginning of the growing season but had depressed growth and yield at the harvest. Oilcake 2X-treated rice in early growing season, especially, showed better growth and development than rice treated by other nutrient sources but was severely lodged at the harvest season due to the typhoon. Compost treatment with high C:N ratio slowly released inorganic N and produced poor rice growth and yield; however, it recued rice lodging. N uptake was the greatest for the oilcake 2X and vetch+rye treatments but the lowest for the compost, which was the similar pattern to the N use efficiency; the greatest and lowest N use efficiency was observed for the oilcake 2X (55%) and compost (5%), respectively. CONCLUSION(s): Rice lodging should be prevented by reducing the excessive nitrogen supplement, resulting from the lower C:N ratio of the organic materials as well as prevented by the radical midsummer drainage. Vetch+rye treatment with 25:1 of C:N had optimum vegetative growth and reduced rice lodging, which increased N use efficiency and yield.

• Korean Journal of Applied Biomechanics
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• v.17 no.1
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• pp.191-199
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• 2007

This study was conducted to examine the biomechanical characteristics of open spike in the volleyball to improve the technique of the volleyball spike. The subjects were six male college and high school athletes. The motions of volleyball spike were filmed by using two Sony VX 2000 Video Cameras. The mechanical factors were angle and angular velocity of body segments in the upper and the lower limbs. The conclusions were as follows; 1. The angle of the shoulder joint of the skilled showed larger than that of the unskilled in impacting of the volley ball spike. 2. The angle of the elbow joint of the skilled showed larger than that of the unskilled in impacting of the volley ball spike. 3. The angle of the wrist joint of the skilled showed smaller than that of the unskilled in impacting of the volley ball spike. 4. The angle of the hip joint of skilled showed larger than that of unskilled in impacting of the volley ball spike. 5. The angle of the knee joint of the skilled and the unskilled showed same in take off and impacting of the volley ball spike, and that of the skilled showed smaller than that of the unskilled in take-off touchdown and touchdown after impact of the volley ball spike. 6. The angle of the ankle joint of skilled showed larger than unskilled in take-off of the volley ball spike. 7. The angular velocity of the shoulder joint, elbow joint, wrist joint of the skilled showed faster than that of the unskilled in impacting of the volley ball spike. Taken together the result of them, I have come to conclusion that knee joint angle in touchdown of the take off should be decreased and knee joint angle in take off should be increased, and then stability of the take off should be made and, and that extension of the elbow joint should be made and wrist joint angle decreased and shoulder and hip joint angle increased, and then C.O.G of the arm and hand should be positioned ahead C.O.G of the body in impacting for effective impact of the spike, and that the transfer of the angular velocity of body segments for effective impact of the spike make from the proximal segment to the distal segment at spike in volleyball.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.1
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• pp.33-39
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• 1996

The aim of this study is to estimate the prevalence of obesity and factors with it Ulsan secondary school girls. A cross-sectional study involving a sample of 485 students aged 12 to 15 years was obtained form secondary schools. Obesity was determined using body mass index(BMI=wt/Ht$^2$). The findings revealed that the average BMI was 19.3, and 4.5% of girls were either overweight and obese(BMI$\geq$25). Subjects were grouped into three categories based on the BMI, sibling obesity, self-consciousness of obesity, eating patterns such as eating snack after dinner and prejudice in food selection, and food frequency score were significantly associated nth BMI, while nutrition knowledge score was not associated with BMI. The fact that several social, environmental and health factors are associated with obesity means that a multisectorial intervention program must be considered in order to decrease the problem of overweight among secondary girls. Such program should include dietary intervention to modify food habits, nutrition education through mass media, introducing information on prevention and control obesity in school curriculum, and allocating sufficient time in the school schedule for exercise activities.

• Korean Journal of Environmental Agriculture
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• v.9 no.2
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• pp.143-151
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• 1990

This study was carried out to investigate the influence of different types of nutrient solutions and culture media on the growth and quality of cucumber(Cucumis sativus L.) and tomato(Lycopersicon esculentum Mill.). The results are summarized as follows : 1. The growth and yield of cucumber and tomato were best in rockwool culture with Cooper solution. 2. In sand-sack culture, growth and yield of cucumber and tomato were higher with compound fertillzer solution. 3. Growth and yield of cucumber and tomato were more effective in rockwool culture than in soil culture in early growth stages, and vice versa in later growth stages. 4. Vitamin C contents of cucumber and tomato showed no differences between soil cultures and hydroponics, except rockwool culture with compound fertilizer solution. 5. The dry weight, total-N, and mineral content of cucumber and tomato showed no differences among all types of hydroponics.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.699-705
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• 1997

This experiment was conducted to find out an optimum direct seeding date for rice in the southern alpine area of Korea as direct seeding method being considered as the most labor-saving method. A cultivar which was sprouted, Keumobyeo, was sown on the surface of flooded paddy from April 25 to May 15 with 5-day interval. The growth characters such plant height, tiller numbers, yield and its components as well as air temperatures were observed. Earlier sowing showed longer plant height and greater tillers than later sowing. Accumulated temperatures in the different growth stages varied from 1,010 to 1,052$^{\circ}C$ during the period from seeding date to maximum tillering stage, and from 1,785 to 1,846$^{\circ}C$ during the period from seeding to heading dates. The growth of rice sown up to May 5 showed comparatively good when compared to that of machine-transplanted rice, even though the grain yield was not competitive to that of machine-transplanted rice. Highly negative correlation coefficients were found between accumulated temperature during the period of first 30 days after seeding dates and the number of panicles, the number of spikelets per square meter, and grain yield. Regression equation between direct seeding date(X) and yield(Y;MT /ha) was $\hat{Y}$ =3.80990＋0.06207X-0.00174 $X^2$($R^2$=0.704), from which optimum seeding date for direct seeding method in alpine area was estimated to be on April 25 to May 1.

• Korean Journal of Organic Agriculture
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• v.27 no.1
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• pp.77-86
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• 2019

This study was carried out to investigate the effect of legume cover crop culture on earthworm fauna in organic farmland. We compared sod culture with two kinds of legume crops of hairy vetch and crimson clover on organic citrus orchard to natural sod culture and conventional orchards in Jeju Island. We analyzed the soil characteristics and investigated the density of earthworms from the orchards. Organic matter content did not show much difference in soil analysis between organic and conventional orchard. But the biomass of earthworms in organic orchards is 3.8 times to 7.0 times higher than that in conventional cultivated orchards, and individuals of earthworms on organic orchards were 2.3~18 times higher than conventional orchards. The biomass of earthworms on hairy vetch and crimson clover cultivation was 44.8 g, 47.2 g in 2016, and 78.7 g, 31.8 g in 2017, respectively, which were higher than 32.8 g and 9.5 g of those on natural sod cultivation. Through this study, we found that hairy vetch and crimson clover cultivation improve the earthworm occurrence density in the soil on organic citrus orchard.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.4
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• pp.323-330
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• 2008

This study was carried out to evaluate the effect of application of cattle manure and chemical fertilizer on dry matter productivity and nutritive values of rye and hairy vetch according to two different sowing methods such as single or mixed-sowed cultivation. Dry matter and TDN yields for rye single culture, and rye and hairy vetch mixed culture were 7.2 and 4.0 ton/ha, and 8.0 and 4.4 ton/ha, respectively. They were significantly (p<0.05) higher than that (4.5 and 2.7 ton/ha) of hairy vetch single culture. Moreover, plots produced by mixed-sowing cultivation had a higher crude protein (CP) as 7.7% than that of only rye plot, and higher TDN and RFV as 55.8 and 79.4%, respectively. Within rye alone plots, completely cattle slurry application produced significantly higher annual DM and TDN yields (7.4 and 4.1 ton/ha) than those of P+K fertilization (7.2 and 3.9 ton/ha) as a chemical fertilizer and non-fertilizer (5.5 and 3.1 ton/ha). Cattle slurry application plot revealed 75.52 and 78.97% of N+P+K fertilization plot for annual DM and TDN, respectively. Within mixed-sowing cultivation with rye and hairy vetch, completely cattle slurry application produced 7.6 ton/ha DM and 4.5 ton/ha TDN, showing 79.50 and 86.77% of N+P+K fertilization plot, respectively. Furthermore, the CP content for cattle slurry plots was 8.5%, which was significantly (p<0.05) higher than those of other plots, and it was also highest in TDN (58.3%) and RFV (86). Overall, rye mixed-sowing with hairy vetch rather than rye alone sowing reduced DM yields, but leaded to enhancement of feed value and nutritive yields. And also, it would be expected that cattle slurry application in comparison with chemical fertilizers might result in reutilization of resources, improved forage quality and, extended harvest period by preventing feed value from rapidly deteriorating.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.3
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• pp.156-164
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• 2004

This study was conducted to evaluate the effect of the application of green manure in the form of either green barley and Chinese milkvetch in reducing the amounts of N fertilizers and conventional fertilizers needed for paddy rice. Prior to rice transplanting, the green barley and Chinese milkvetch as a green manure produced respectively $668kg\;10a^{-1}$ and 3,492kg\;$10a^{-1}$ in fresh shoot weight basis. Calculated nitrogen content from harvested green manures was 3.9 and $17.8kg\;10a^{-1}$, respectively. Plant height and tiller number of rice increased when two kinds of green manure incorporated into soil. Above mentioned parameters also increased with increasing amounts of N fertilizers at both ear formation and heading stage of rice. Rice grain number was not affected by green manures treatment but increased when N fertilizers were applied. Although rice panicle and grain number increased with green manure treatments and fertilizer applications, whereas the percentage of ripened grain decreased. Chinese milkvetch with additional N fertilizer applications increased brown rice yield from 1 to 5% compared to rice yields in plots where non-green manure with the conventional amount of fertilizer application was applied. Rice treated with Chinese milkvetch and 30% of the conventional N fertilizer rate yielded the same as rice fertilized conventionally. During the rice growing season, $NH_4-N$ content of paddy soil was higher in green manures treatment than non-green manure one. Average $NH_4-N$ content in paddy soil drastically decreased after heading stage below $5.7mg\;kg^{-1}$ in non-green manure treated plots. While on the other, $NH_4-N$ content in soil slowly decreased in plots those were treated with green manures at harvesting stage, average $NH_4-N$ content was still greater than $5.5mg\;kg^{-1}$. Nitrogen content of rice shoot and brown rice seed was higher in green manure treatment.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.3
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• pp.127-133
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• 2005

The measurement technique using laser distometer to estimate soil erosion on sloped upland was assessed for its possibility for application. This technique was practiced in lysimeter installed in Chuncheon and Pyeongchang in 2001. The lysimeter installed at Chuncheon has 12% slope, 10 m slope length, 2 m width, and soil texture was sandy loam, while the lysimeter installed at Pyeongchang showed 23% slope, 15 m slope length, 5 m width, and sandy loam soil. Change of surface soil height was monitored using laser distance meter before and after rainy season on same spots. The Investigated periods in Chuncheon and Pyeongchang were from 22 June to 22 September and from July to October, respectively. Precipitation in Chuncheon and Pyeongchang in this period was 892.2 and 931.9 mm, respectively. Rainfall over 60% of annual precipitation was concentrated on July and August in Chuncheon and September and October in Pyeongchang, respectively. By monitoring the change of surface soil height using laser distance meter before and after rainy season, eroded soil surface in up-down fallow field in Chuncheon was 0.874 cm, while eroded soil surface in slant furrow field in Pyeongchang was 1.127 cm, which correspond to 79.5 and $98.0MT\;ha^{-1}$. Soil erosion increased as furrow length increased. Amounts of estimated soil loss using laser distance meter was 0.98-1.18 times higher compared to the estimated values through Iysimeter experiment, which implies possibility for application to monitor soil loss particularly in up-down and slant furrowed field. However, in the lysimeter with contoured tillage, amount of estimated soil loss using laser distance meter was approximately a half compared to that from lysimeter experiment, which implies inadequacy of distance meter application in contour- tillage field. The great soil loss difference between distance meter and lysimeter might be caused by disruption of some of the contoured furrows in lysimeter. The measurement technique using distometer in this study could be useful to estimate soil loss especially in up-down and slant-tillage fields.