• Journal of the Korean Ceramic Society
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• v.18 no.4
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• pp.257-261
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• 1981

The tendency of glass containing titanium-dioxide to separate into two phases can be attributed to a change of the coordination number of titanium from six to four on increase of temperature and to "freezing" of the high temperature four fold coordination on cooling of the melt. Addition of TiO2 to the basic glass 8.7 $Na_2O$ 22.4B2O3 68.9 $SiO_2$ was varied 5 to 25 parts. The phase separation in the temperature range of transformation was examined with each heating temperature and soaking time. As the experimental results, the most distinct phase separation were obtained from alkali extraction method when $TiO_2$ was added 15 parts. The apparant activation energy was 30.5 Kcal/mole by alkali extraction method derived from Arrhenius plots.ius plots.

• Journal of Plant Biology
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• v.17 no.2
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• pp.95-98
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• 1974

This experiment was undertaken with the purpose of investigating effect of gibberellin on the growth and electron microscopic ultrastructure of hop(Humulus lupulus var. Hallertau) shoot apex. The results are as follows. 1) The growth of stem in the plots treated with GA(10, 25, and 50ppm) is more predominant than control. The leaves and cones of treated plots turn to pale green. 10ppm plot of GA treatment is the most effective in growth and yield than the others. 2) Under the GA-treated condition, it is believed that the nucleoplasmic index (NP) are higher than the control, and so nucleus, nucleolus, mitochondria, primary cell wall, middle lamella, and etc. tends to be larger than the control. 3) Mitochondria contained in the cell of shoot apex treated with concentration of 10ppm GA was seemed to increases in number and be larger in size than the control.

• Korean Journal of Plant Resources
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• v.17 no.2
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• pp.102-106
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• 2004

To determine the optimal planting density of wanggol in southern areas of Korea, Gangsan early local, the highest yielding variety was grown under four different plant density. Yield components such as stem length, number of tiller, stem diameter were highest at the plots with 18 cm row spacing and 18 cm plant spacing. Dry cortex and medulla yield were highest at the plots of 18 cm row spacing and 18 cm plant spacing. Judging from the results reported above, at optimum planting density of wanggol seemed to be 18 cm row spacing and 18 cm plant spacing.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.1
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• pp.100-103
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• 2007

A field experiment was conducted in Agronomy farm at an altitude of 1350 m. above sea level in a randomized complete block design with three replications and eight treatments on vegetable type soybean in 2005. The objective was to see the effect of vermicompost alone and in combination with Rhizobium inoculum and mineral fertilizers on the yield of vegetable soybean. The result showed higher number of nodules from the non inoculated plot, however, the nodules weight was highest from the inoculated plots. No significant difference was notice statistically on roots and shoots dry weight. Soybean grain was obtained highest (32.3%) over the non inoculated plot followed by vermicompost plus inoculated, however, there was non significant difference. There was a slight increment on grain and straw yield from the inoculated plots over the non inoculated.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.4
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• pp.117-126
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• 1988

This paper attempts to characterize general tendency in water level fluctuations at paddy fields, that may be important to efficient irrigation water uses Banweol district was chosen to be the study area, and water levels among irrigation practice parameters were measured daily throughout the irrigation periods of 1985-1986. Time series analyses showed that water levels at fields have strong serial correlationships. A rather long term periodicity was also observed from spectral analyses. Correlationships between water levels at adjacent fields ranged 0.4-0.9, indicating wide variations in irrigation practices. The water levels showed little correlationships with meteorological factors like evapotranspiration, nor with irrigation practices like water supply rates. Standard errors of the average water levels were computed for different number of field plots within a block. The results indicated that low level areal coverage of gauging plots may be applied for field monitoring of daily water level fluctuations.

• Asian Journal of Turfgrass Science
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• v.1 no.1
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• pp.18-29
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• 1987

This study was carried out to examine the effect of nitrogen application and clipping interval on the characteristics of several turf components of korean lawngrass for the basic data of lawn management. It was treated by Split plot design with three replications. The main plots were nitrogen levels with 0, 350, and 700kgN / ha, and the sub plots were clipping intervals with 10, 20, and 30 days The results obtained are summarized as follows ; 1. Increasing the rate of nitrogen fertilizer and frequent clipping increased tiller number of korean lawngrass and the maximum number of tillers obtained in October were recorded from 700kgN application and clipping treatment of 10 days interval. Meanwhile, treatment of 350kgN with 10 days clipping interval increased tillers much more than those of 700kgN with 20 and 30 days clipping intervals. 2. The average number of green leaves occurred during the growth period maximized by applying 700 kgN and clipping 10 days interval. 3. Increasing tiller numbers significantly decreased tops DM weight per tiller by clippng plants at interval of 10 and 20 days, irrespective of nitrogen applied, and with nil N, at the interval of 30 days. By applying 700kgN however, tops DM weight per tiller increased as the number of tillers increased consistently. 4. The highest tops DM weight was achieved from late August to early September by applying 350 and 700kgN. 5. During the growth period, nitrogen application increased unders(stolon+root) DM weight, and, at the same level of nitrogen applied, the increase in stolon DM weight enhanced by lengthening the clipping interval to 30 days. 6. Nitrogen efficiency to green leaves, stolon nodes and DM weight of root with high nitrogen was achieved as clipping interval was shortened.

• Applied Biological Chemistry
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• v.15 no.1
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• pp.85-92
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• 1972

The field experiment was performed to investigate the effects of various kinds of phosphorus fertilizers such as double superphosphate, fused magnesium phosphate and Simagcarin (both the Kyun-gi Chemical Co, products) on the physiological roles in development of root system, growth and yield compositions of rice plant. Radioactive phosphoric acid $(H_3\;^{32}PO_4)$ was applied to measure the root activity. 1. The number of total tillers was significantly increased in double superphosphate plots, but the rate of fruitful tillers was more numerous in the fused magnesium phosphate and the Simagcarin plots than that of the other plots. 2. The grain yield was much more obtained in the fused magnesium phosphate and Simagcarin plots (no significant difference were found between both of plots) than the double superphosphate and control plots. It seemed due to the increasing of seedbearing rate and number of fruitful tillers. 3. In double superphosphate plots, root system was mostly developed near topsoil areas, but fused magnesium phosphate and the Simagcarin plots, root system was uniformly distributed from topsoil to subsoil areas. 4. As the results of those experiments, fused magnesium phosphate and Simagcarin was demonstrated to be soil amendmentical materials rather than the phosphorus fertilizers, especially in low productive paddy soils which lack the special mineral nutritions.

• Journal of Korean Society of Forest Science
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• v.23 no.1
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• pp.17-27
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• 1974

In order to investigate the variation of nutritive value, fertilizer value, productivity and growth performance by the number of cutting times in Lespedeza bicolor, Lespedeza maximowiczii and Lespedeza japonica var. intermedia, the plots of one, two and four cutting times in a year had been made through 1972 to 1973. The results are summarized as follows. 1. Lespedeza bicolor, Lespedeza maximowiczii and Lespedeza japonicavar. var. intermedia showed increase of growth and productivity in two plots excluding the plots of four time cuttings. 2. Significant differences at 1% level were shown among the species and the number of cutting times in total grass yield. Lespedeza bicolor showed the greatest production, and followed by Lespedeza maximowiczii and Lespedeza japonica var. intermedia. The plots of one cutting time a year produced more dry weight than that of two and four cutting times. The production in plots of fourth cutting showed less growth and yield. 3. The ratios of dry weight to fresh weight and of leaf weight to stem weight were decreased when the number of cutting times increased in Lespedeza bicolor, Lespedeza maximowiczii and Lespedeza japonica var. intermedia. 4. Crude protein was decreased, though crude fiber content was increased when the grasses were growing more and more. Conent of crude fat showed great variation by the number of cutting times and cutting period seoson. 5. Early cut tings of Lespedeza showed higer fertizer value than late cuttings in all the species. 6. It is suggested that two and three time cutting through a year in Lespedeza bicolor and Lespedeza japonica var. intermedia having high nutritive and fertilizer value is good when using the Lespedeza species as a fodder or manuers, and one time cutting a year will be good when using the Lespedeza species as a fuel.

• The Korean Journal of Ecology
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• v.20 no.5
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• pp.367-373
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• 1997

The effects of salinity on the growth and production of rice were studied at Seosan reclaimed land from July to October, 1995. The plant height, the number of living aleaves, dead leaves and total leaves, the number of the grains and the dry weight of the grains per individual, and the dry weight of above the ground in $25cm{\times}25cm$ quadrat were investigated on 5 plots whers were different salinity. The plant height, the number of living leaves and total leaves and the number of grains and the dry weight of grains per individual, and the dry weight of above the ground decreased as the salinity of water increase and the number of dead leaves of rice increased as the salinity of water decrease. The effect of salinity on the reproductive production is severer than the vegetative production. Because of the salinity, the growth and the production of the rice at Seosan reclaimed land are worse than the normal rice field.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.323-326
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• 2006

Numerical solutions for spin-up problem of a thermally stratified fluid in a cylinder with an insulating sidewall and time-dependent rotation rate are presented. Detailed results are given for aspect ratio of O(1), fixed Ekman number $10-^{4}$, Rossby number 0.05 and Prandtl number O(1). Angular velocity of a cylinder wall changes with following formula, $\Omega_f=\Omega_i+\Delta\Omega[1-\exp(-t/t_c)]$. Here, this $t_c$, value, which is very significant in present study, represents that how fast/slow the angular velocity of the cylinder wall reaches final angular velocity. The normalized azimuthal velocity and meridional flow plots for several tc value which cover ranges of the stratification parameter S(1 ~ 10) are presented. The role of viscous-diffusion and Coriolis term in present study is examined by diagnostic analysis of the azimuthal velocity equation.