• 한국초지조사료학회지
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• 제16권2호
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• pp.169-176
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• 1996

An experiment was carried out to determine the effect of cultivar and tedding frequency on changes of moisture content of oat(Avena sativa L.) hay during field drying and on quality of baled oat hay after storage. The experimental design was a split-plot with the four oat cultivm such as 'Magnum', 'Cayuse', 'West' and 'Murray' as main plots and the two tedding frequencies such as 1 or 3 times a day as subplots in three replications. Moisture content of fresh cut oat cultivar was higher in the order of 'Magnum', 'Cayuse', 'West', and 'Murray' and the moisture content difference among the cultivm was maintained to the final curing day(P< 0.05). Moisture loss from the oat hay during the last 3 curing days was greater with 3 tedding a day than I tedding a day. Temperature of baled oat hay began to rise critically from the 6th day of storage and wa5 highest in 'Magnum' oat cultivar($45.3^{\circ}C$). Total nitrogen and ADIN contents of late maturing oat hay 'Magnum' and 'Cayuse' were higher than those of early maturing 'Murray' and 'West'. Tedding frequency did not influence total nitrogen and ADIN contents. ADF and NDF contents of early maturing oat hay were higher than those of late maturing oat hay. Relative feed value (RFV) of 'Magnum' oat hay was the highest(l06) and classified as Grade 2 in forage quality standard. Quality grade difference between early and late maturing oat cultivan was only 1 or 2.

• 한국자원식물학회지
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• 제19권6호
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• pp.692-696
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• 2006

This study was conducted to evaluate the effect of seed disinfectant, in control of brown leaf blight, growth characteristics, and dry root yield in the cultivation of Alisma plantago after early maturing rice cropping. Experimental plot was laid out in split plots design with three replications. The major seed disinfectants were benomyl Wp, 20%, Captan Wp, 50%, Triferine Ec, 17%, Etridia zole Ec, 25%, and Thioplant-mythyl Wp, 50%. Even though seed disinfectant treated had no effect on the growth and flowering date of Alisma plantago, dry root yield was increased largely with benomyl Wp, 20%, in seed disinfectant than in the other seed disinfectants and contorl. All seed disinfectants had no injury with standard dosage. But all seed disinfectants had slight injury in the double dosage level for the Alisma plantago. On the basis of yield, vegetative and disease paramerer, benomyl Wp (20%) ($100g/20{\ell}$) had shown superior performance, however, all the seed disinfectants are effective as compare to without treatment.

• Structural Engineering and Mechanics
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• 제77권1호
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• pp.103-114
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• 2021

Ultra high strength concrete (UHSC) originally proposed by Richards and Cheyrezy (1995) composed of cement, silica fume, quartz sand, quartz powder, steel fibers, superplasticizer etc. Later, other ingredients such as fly ash, GGBS, metakaoline, copper slag, fine aggregate of different sizes have been added to original UHSC. In the present investigation, the combined effect of coarse aggregate (6mm - 10mm) and steel fibers (0.50%, 1.0% and 1.5%) has been studied on UHSC mixes to evaluate mechanical and fracture properties. Compressive strength, split tensile strength and modulus of elasticity were determined for the three UHSC mixes. Size dependent fracture energy was evaluated by using RILEM work of fracture and size independent fracture energy was evaluated by using (i) RILEM work of fracture with tail correction to load - deflection plot (ii) boundary effect method. The constitutive relationship between the residual stress carrying capacity (σ) and the corresponding crack opening (w) has been constructed in an inverse manner based on the concept of a non-linear hinge from the load-crack mouth opening plots of notched three-point bend beams. It was found that (i) the size independent fracture energy obtained by using above two approaches yielded similar value and (ii) tensile stress increases with the increase of % of fibers. These two fracture properties will be very much useful for the analysis of cracked concrete structural components.

• 한국초지조사료학회지
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• 제20권2호
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• pp.115-122
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• 2000

This study was carried out to determine a fertilization rate for productivity and nutritive value improvement of silage corn, using two kinds of composts, and to examine the potential possibility of utilization as an organic fertilizer. The experiment was conducted on the field plot at Gongiam, Kwangju, Kyunggi-Do for 3 years, from 1996 to 1998, and arranged in split-plot design with three replications. The main plots were two kinds of composts such as swine manure fermented with sawdust (SMFWS) and swine manure fermented without sawdust (SMF). Subplots were the nitrogen fertilization rates (0, 100, 200, 300 and 400kgN/ha/year). The dry matter (DM) yield increased as the nitrogen fertilization rate increased up to a rate of 300 kg N/ha, but decreased at rate of 400 kg N/ha. Dry matter yield in SMFWS treatment was higher than that of SMF treatment, but there was no significant difference between SMFWS and SMF treatments. Net energy for lactation (NEI) and total digestible nutrients (TDN) in corn increased as the fertilization rate of SMFWS and SMF increased, and crude protein (CP) content increased by the fertilization of SMFWS and SMF. No difference of CP, NEI and TDN was found between SMFWS and SMF treatments.

• 농업과학연구
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• 제42권3호
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• pp.151-158
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• 2015

This study was conducted to know the variation and relationship of rice grain quality and starch pasting properties by transplanting times. Two early maturing rice cultivars which accounted for the most area of early maturing rice cultivar in Chungnam province were used. The experiment was laid out in a split-plot design with 3 replications. The main plot consisted of three transplanting times viz. early (April 25), ordinary (May 25) and late (June 25) with sub-plots containing two cultivars. According to the transplanting times, most of rice grain quality and starch pasting properties showed significant difference and Joami showed higher grain quality than Unkwang in all transplanting times. Especially, rice grain quality was improved when transplanted late, showing high head rice and glossiness of cooked rice due to the lower mean temperature during grain filling stage. Glossiness of cooked rice was positively correlated with head rice ratio, amylose content and setback value, and negatively correlated with chalky rice ratio and protein content. The highest positive and negative correlation were observed between breakdown value and peak viscosity ($r=0.98^{**}$), and breakdown and setback ($r=-0.94^{**}$), respectively. These results provide some information for rice researchers and producers producing cultivars with an improved quality, suggesting that rice quality is highly influenced by temperature at grain filling stage, and transplanting times is crucial in improving rice quality. In addition, starch pasting properties are useful for determining rice quality because rice grain quality and starch pasting properties are dependent on each other.

• Journal of Ecology and Environment
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• 제33권4호
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• pp.299-306
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• 2010

The use of local seed provenance is often recommended in forest restoration. Early vigor is a combination of the performance of seed germination and emergence after planting. The ability of young Brant's oak plants to grow and develop after emergence and its dependence on local habitat conditions was investigated in this study. The effects of seed source and shade on early growing seedlings of Brant's oak (Quercus brantii L.) were determined in field measurements. Seeds of Quercus brantii L. were collected from 4 forest areas (seed sources) in southern Zagros (Provinces of Kohkilouyeh-Bouyer Ahmad and Fars) at altitudes of 850, 1,100, 1,500, 2,100 m a.s.l., and planted in a nursery constructed in southwestern Iran. According to a split-plot design consisting of four blocks, each containing two main treatment plots (no shading, partial shading), each main plot was sub-divided into four sub-plots (for elevations of 850, 1,100, 1,500 and 2,100 m). Results showed that shade treatments had significant effects on emergence percentage and rate, shoot length, shoot dry weight (SDW), root dry weight (RDW), leaf area (LA), and chlorophyll content. Ecological factors also had an effect on seed performance. Altitude of seed source had a very significant effect on root length, LA, SDW, and RDW. The seeds collected from 850 m a.s.l. elevation showed the highest performance, especially in leaf area, root length, shoot dry weight, and root dry weight. Our results showed that the altitude of 850 m a.s.l. was the best for collecting Brant's oak seeds.

• 한국초지조사료학회지
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• 제25권1호
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• pp.17-22
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• 2005

This experiment was conducted to investigate the effect of seeding dates and rates on the productivity and nutritive value of hairy vetch(Vicia villosa Roth) at experimental field of Grassland and Forage Crops Division, National Livestock Research Institute, RDA, Suwon from 1999 to 2000. The experimental design was consisted of split-plot design with three replications. The main plot was seeding dates(25 Aug., 15 Sep. and 5 Oct.) and the subplot was seeding rates(20, 30 and 40 kg/ha). Late seeding dates increased the plant height and delayed the flowering stage as 1 or 2 days. The dry matter(DM) content was decreased with low seeding rates, and the trend was same in the all plots. Average crude protein(CP) content was $24.1\%$ and increased with delayed seeding date and lower seeding rate. The content of acid detergent fiber(ADF) and neutral detergent fiber(NDF) was increased with higher seeding rate, but seeding date did not affect. In vitro dry matter digestibility(IVDMD) of hairy vetch tended to decrease with high seeding rate, and total digestible nutrient(TND) did not show significant difference among seeding rates. Average relative feed value(RFV) of hairy vetch showed 140 which means very high quality. Dry matter and CP yield was decreased with delayed seeding date. The results of this experiments indicated that seeding in middle-August with 40 kg/ha would be recommended to produce the highest yield and quality f3r the cultivation of hairy vetch in middle part of Korea

• Journal of Plant Biology
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• 제15권1호
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• pp.33-41
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• 1972

Nine shrub layer communities under two relatively well conserved natural summer green forests in the central region of Korean Peninsula were studied for the pattern of stem distribution in terms of Greig-Smith's multiple split-plot experiment and for the association between the population of the two main species in terms of Kershaw's covariance analysis respectively. Four contiguous belt transects, $4{\times}64m size with 1{\times}1m$ basic unit, were set in each shrub layer communities. Significant primary clumps with $1{\times}1m or 1{\times}2m$ dimension wer observed consistently throughout the nine study sites. The primary clumps themselves were significantly distributed either regularly or at random. The association between the two principal species of each shrub layer is highly significantly either positive or negative in $1{\times}1m or 1{\times}2m$ dimension. As the plot size increases from $1{\times}1m to 8{\times}8m$ the associational trends were changed from negative to positive direction in one forests. But the change from positive to negative direction and the consistent negative association were also observed from the other forest. All of the association trends were observed only from $1{\times}1m to 4{\times}4m$ dimension. These results are suggestive that the distributional pattern of the shrub layer species under the summer green forest is simple mosaic fashioned with $1{\times}1m or 1{\times}2m$ dimension. The rest of the principal species are located in that matrix. The simple mosaic pattern of two principal species are located in that matrix. The simple mosaic pattern of two principal species seems to be controlled by change in micro-environmental pattern. Differences between the primary random group and clumped group among sites also suggest that competition exists for light or/and soil between primary clumped groups.

• 한국초지조사료학회지
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• 제12권3호
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• pp.153-160
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• 1992

본 시험은 고령지 두과목초의 적응성을 구명하기 위하여 표고가 다른 3개지역(600,800,1000m a.s.l)에서 주구를 파종시기(추파.추파), 세구를 혼파조명(알팔파-화본과, 레드크로바-화본과, 화이트크로바-화본과)으로 두고 분할구 배치 3반복으로 수행하였다. 1.600m에서 두과목초의 적응성을 보면 알팔파, 레드클러버 및 화이트클로버 공히 추파를 했을 때 연차간 악화없이 약 30%를 유지하여 적응성이 매우 양호하였다.2. 800m에서는 화치트클로버를 춘파하므로써 연차간에 심한 감소없이 최종 예취시 약 14.0%를 점유하고 있었으며 또한 10a당 건물수량이 가장 많았다. 3. 1000m에서도 800m와 비슷한 경향으로 화이트클로버를 춘파했을 경우 어느정도 적응이 가능하였다. 4. 표고별 두과목초의 비솔 및 수량이 표고가 증가 할수록 현저하게 감소하였으며 알팔파는 800m 이상에서는 생육이 거의 불가능하였다.

• 한국작물학회지
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• 제7권1호
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• pp.133-137
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• 1969

This experiment was conducted to determine the optimum row width and plant spacing within row under the tropical environment for a leading soybean variety Palmetto and it was carried out at Eakmat Experiment Station in Vietnam. The experiments were arranged in a split plot design with four replications and the test was repeated twice in two years. Variations for seed yield due to the distance between rows were significant at 1 per cent level in 1967 test(dry season growing) and at 5 per cent level in 1968 test. Significant differences for plant height, lodging, maturity, number of branches per plant, and number of pods per plant due to the row width were not found in both tests, while significant differences in difference spacing within row was found in all traits studied. Interaction between width of row and spacing within row for seed yield and plant height were found at five percent level in 1967 test. These results indicate that close planting may increase in seed yield and plant height in both seasons, and decrease in loadging. From these studies, one could be understood that the plant population, particularly in dry season, plays decisive roles on seed yield in soybean culture, and the maximum plant height and minimum value of lodging index were also observed in closest spacing plots. The highest soybean yield in late planting would be expected by a combinations of 30 cm(between rows)${\times}$5cm(between hills) plot, while 40cm ${\times}$ 5cm planting method would be suggested for rainy season growing. Highest seed yield was obtained at closet spacing in both dry and rainy season, and these results led to drilling method in seeding where about 20 seeds per meter of row could be recommended. Besides the seed yield, the close planting may produce some advantages, such as increase plant height and decrease lodging, weeds and erosion of surface soil.