• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1720-1723
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• 2000

Boron doped conducting diamond thin film were grown on Si substrate by microwave plasma chemical vapor deposition from a gaseous feed of hydrogen, acetone/methanol and solid boron. The doping level of boron was controlled from 0ppm to $10^4$ppm (B/C). The Si substrate was tilted ca. 10$^{\circ}$ to make Si substrate have different height and temperature. Experimental results show that same condition but different temperature of Si substrate by height made different crystalline of diamond thin film. There were appeared 3$\sim$4 step of different crystalline morphology of diamond. To characterize the boron-doped diamond thin film, Raman spectroscopy was used for identification of crystallinity. To survey surface morphology, microscope was used. Grain size was changed gradually by different temperature due to different height. The Raman spectrum of film exhibited a sharp peak at 1334$cm^{-1}$, which is characteristic of crystalline diamond. The lower position of diamond film position, the more non-diamond component peak appeared near 1550$cm^{-1}$.

• Journal of Power System Engineering
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• v.17 no.4
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• pp.72-78
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• 2013

Compacted graphite iron 340 was carried out the heat treatment from 873 to 1,273 K. Compacted graphite iron 340 was evaluated relationship between the sound velocity, the attenuation coefficient and the tensile strength. The obtained results are as following. The signal strength of C scan images were weak according to increasing of heat treatment temperature and time. The amplitude of A scan and B scan was also low. This can be cause that the graphite was grown into the type of vermicular, and the many of grain boundary with ultrasound scattering were increase. The sound velocity was depend upon the heat treatment temperature and time, the attenuation coefficient had nothing to do with the temperature and time. The higher the heat treatment temperature, the tensile strength and the sound velocity were decreased. However, the tensile strength was proportional to the sound velocity. The higher tensile strength, the faster the sound velocity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.11
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• pp.1-9
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• 1972

For a measure against late transplanting, this experiment was conducted to investigate a reasonable seeding rate in nursery bed and a proper nursery size. The treatments applied to this experiment are as follows a) seeding rates: 0.2ι, 0.4ι and 0.6ι per 3.3$m^2$ b) nursery sizes. for 10a-field area: 39.6$m^2$, 49.5$m^2$ and 59.4$m^2$ c) transplanting dates: June 5, June 25 and July 15. The seeding date was April 26 and planting density was determined by the number of sound seedlings based on the combination of seeding rate and nursery size. The results may be summarized as follows: 1. In seedlings both increased nursery period and decreased seeding rate showed a remarkable-increase in plant height, number of leaves, dry matter weight and the ratio of dry weight to plant height. But their number of tillers and live leaves did not show such tendency. 2. Delayed transplanting date shortened culm length and panicle length as well as number of days from transplating to heading and it also delayed heading date. On the other hand the transplanting of 80-day seedlings resulted in premature heading. 3. As a result late transplanting reduced number of spikelets per panicle, maturing rate and 1000-grain weight. In the last analysis it linearly reduced grain yield. The decreasing rate of yield by late transplanting was 15.6% in June 25 plot and 41. 3% in July 15 plot, compared with the yield in June 5 plot. Such a remarkable decrease in yield of the extremely late transplanted plot was mainly due to markedly decreasing number of spikelets per panicle and 1000-grain weight. 4. Both increased seeding rate and nursery size gave a rise in number of tillers per unit area as well as number of transplanting hills but gave a fall in culm length and panicle length. 5. Accordingly, though thick seeded - dense planted plot increased number of panicles per unit area, decrease in number of spikelets per panicle and 1000-grain weight made no differences in yield between thick seeded - dense planted plot and thin seeded - sparse planted one. However, the yield in the thick seeded - dense planted plot transplanted on July 15 was reduced owing to the remarkable decrease in maturing rate and 1000-grain weight. 6. We came to the conclusion that as a measure against the extremely late transplanting the suitable seeding rate was 0.4ι per 3.3$m^2$ and the proper nursery size was 59.4$m^2$ for 10a-field area.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.2
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• pp.78-83
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• 2012

The structural change and the electrical conductivity with Sr content in $La_{1-x}Sr_xMn_{0.8}Cu_{0.2}O_3$ (LSMCu) were studied. $La_{0.8}Sr_{0.2}MnO_3$ (LSM) and $La_{1-x}Sr_xMn_{0.8}Cu_{0.2}O_3$ ($0.1{\leq}x{\leq}0.4$) were synthesized by EDTA citric complexing process (ECCP). A decrease in the lattice parameters and lattice volumes was observed with increase of Sr content, and these results were attributed to the increasing $Mn^{4+}$ ions and $Cu^{3+}$ ions in B-site. The electrical conductivity measured from $500^{\circ}C$ to $1000^{\circ}C$ was increased with increase of Sr content in the $0.1{\leq}x{\leq}0.3$ composition range, and it was 172.6 S/cm (at $750^{\circ}C$) and 177.7 S/cm (at $950^{\circ}C$, the maximum value) in x = 0.3. The electrical conductivity was decreased in x = 0.4 because of the presence of the second phase in the grain boundaries. The lattice volume was contracted by increase of $Mn^{4+}$ ions and $Cu^{3+}$ ions in B-site according to increase of Sr content and the electrical conductivity was increased with increase of charge carriers which were involved in the hopping mechanism.

• Korean Journal of Materials Research
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• v.4 no.5
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• pp.556-565
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• 1994

Effects of Ag addition to 2090 and CP 276 Al-Li alloy systems on the microstructure and mechanical properties have been investigated. The addition of silver up to 0.16wt.% reduced the grain size of the alloys, and was responsible for the formation of finer and more uniform $\delta$'($AI_{3}Li$) and $T_{1}(AI_{2}CuLi$) precipitates in 2090 alloys, even though no variation of precipitates was found in CP 276 alloys. The addition of 0.16wt.% Ag improved the tensile strength of 2090 alloys about 40MPa with the expense of small reduction of percent elongation. However, the small addition of Ag to CP 276 containing Mg did not show any variation of tensile strength and elongation. The aging treatment of these alloys at $150^{\circ}C$ for 70 or 90 hours, depending on alloy systems, showed peak hardness value of about 92 $H_rB$.

• Journal of Technologic Dentistry
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• v.14 no.1
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• pp.55-65
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• 1992

The purpose of this study was to investigate the comparison of physical properties of nonprecious metal alloys colored goldish yellow. The experimental groups were copper based dental alloy and control group was Ni-Cr based dental alloy used crown and bridges frameworks. Hardness was tested by vickers hardness tester, tensile strength was tested by universal tension tester. After testing the tensile strength of castings, the microstrucure and the pattern of fracture were investigated by scanning electron microscope and metallurgical microscope. The results were as follows : Hardness of Ni based alloy was higher than Cu based alloys. Hardness number of A group was 200.41$\pm$16.10 Hv, B group was 194.33$\pm$1.69 Hv, C group was 139.29$\pm$2.19 Hv and D group was 293.81$\pm$27.17 Hv, respectively. Tensile strength of D group was 56.42$\pm$6.17 $kg/m^2$, A group was 50.39$\pm$5.68 $kg/m^2$, C group was 45.13$\pm$4.53 $kg/m^2$, B group was 45.25$\pm$9.25 $kg/m^2$, in order, and D group was maximum tensile strength. The fractured surfaces of tensile specimens in the all groups showed the tendency to form large voids in the center of specimens. Thus the ductile fracture was changed into the brittle fracture with the fine grain size.

• Journal of Agricultural Extension & Community Development
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• v.7 no.2
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• pp.257-277
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• 2000

The objectives of this study are to investigate the relationship between the growth of the horticultural sector and horticultural research and extension and to examine the socioeconomic returns to investment on research and extension in Korean horticulture. Data for horticultural production values, producer price indices and research and extension budgets for horticultural sector from 1965 to 1998 are collected from various sources. Multi-variate time series analysis technique with vector auto-regression model and Akino-Hayami Formula were employed for the analysis. This study finds (1) horticultural production responds about seven years later to the horticultural research investment shock. the magnitude of the impacts increases to a peak in seventeen years from the initial expenditures and then declines slowly thereafter until twenty years. and this peak gives a tip that horticultural research impact lasts much longer than grain's or agriculture's: (2) the social surplus from research investment benefits more to the consumer rather than to the horticultural producer: (3) B/C ratios in horticultural research are quite high with the range of 9 to 55 from 1965 to 1998. but these have been decreased since the early 1990s: (4) the socioeconomic returns to horticultural research is quite high with 56 percents of internal rate of return. It remains to be analyzed returns to investment on extension in horticulture because of no statistic significance in this study.

• Journal of the Korean Professional Engineers Association
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• v.1 no.1
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• pp.18-25
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• 1968

Higher yield in rice paddies is greatly dependent on adequately balanced and timely supply of water. A majority of rice paddy in Korea is generally irrigated by rainfall, but in many cases it has to be supplemented by artificial irrigation for optimum rice culture. Although the water requirement of rice plant is for higher Than that of athec crops, submerged condition of rice paddy is not Necessarily required. The moisture requirement of rice plant varies with its growing stages, and it is possible to increase the irrigation efficiency through reduction of water loss due to percolation in rice paddies. An experimental plots were set up by means of sandomized block design with three duplication; (a) All time submerged, (b) Economically controlled, and (c) Extremely controlled. Three different irrigation periods Were (a) Initial sage, (b) Inter-stage, and (c) Yast stage. The topsoil of the three plots were excavated to the depth of 30 cm and then compacted with clay of 6 cm thickness. There after, they were piled up with the excavated top soils, leveled and cored with clay of 6 cm thickness around footpath in order to prevent leakage. The results obtained from the experiments are as follows, 1. There is no difference among the three experiments plots in terms of physical and chemical conditions, soil properties, and other characteristics. 2. Culm length and ear length are not affected by different irrigation methods. 3. There is no difference in the mature rate and 1, 000 grain weight of rice for the three plots. 4. The control plot which was irrigated every three days shows an increased yield over the all the time submerged plot by 17.8 percent. 5. The clay lined plot whose water holding capacity was held 5 days long, needs only to be irrigated every 7 days. 6. The clay lined plot shows an increased yield over the untreated plot ; over all-the-time submerged plot by 18 percent ; extremely controlled plot by 18 percent, and economically controlled plot by 33 percent. 7. It may be saved in water requirement about one Thirds.

• Korean Journal of Agricultural Science
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• v.35 no.1
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• pp.101-118
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• 2008

This paper reviews the present situation of Triticale cultivation and examines the potentiality of contribution to livestock as well as poultry sector in Bangladesh Agriculture. Triticale is a human-made cross between rye and durum wheat that has the ability to produce quality green fodder, and then re-grow after first and second cutting to produce grain. In Bangladesh, it is a non-traditional cereal that grows well during the cool and dry Rabi season (November-March) when fodder and feed scarcity is a major limiting factor for ruminant livestock. In Bangladesh Triticale was started to grow in the late Ninety's. The scientists of Bangladesh Agricultural Research Institute (BARI) were first introduced triticale in Bangladesh. Still now the situation of Triticale is grown as fooder and feed in Bangladesh within the scientists under trial. High quality grass fodder was obtained by cutting green triticale plants twice, at 35 and 50 days after seeding, while later the ratooning tillers produced grain to a yield of 1.1-2.4 t/ha of grain for poultry feed or human food. Triticale straw was twice as nutritious as rice or wheat straw and its grain contained more protein than other cereals. Researchers and farmers have also successfully made triticale hay and silage from a mixture of triticale green cuttings, rice straw and molasses. A feeding trial at Bangladesh Livestock Research Institute(BLRI), Savar station showed a large(46%) increase in cow live weight gain and a 36% increase in milk yield (but no change in milk quality or dry matter intake) in cows fed triticale silage compared with those fed rice straw over a period of nine weeks. In another feeding trial, it was found that triticale grain was a good replacement for wheat in the feed blend for chickens in Bangladesh. So it will be a good chance to alive our livestock as well as poultry sector if triticale enters to our existing cropping system as fodder cum grain. The challenge in Bangladesh is to identify fodder technologies that match existing small-scale farmer cropping patterns without needing major inputs or increasing risks. Preliminary field experiments revealed that triticale is a crop with good potential to produce quality fodder and grain for small scale farmers in Bangladesh.

• The Korean Journal of Food And Nutrition
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• v.23 no.4
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• pp.641-648
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• 2010

This study attempted to estimate the dietary quality and the food diversity by analyzing the military foodservice menu. To evaluate the dietary quality, an analysis of NAR(Nutrient Adequacy Ratio) and MAR(Mean Adequacy Ratio) were carried out. DDS(Dietary Diversity Score), DVS(Dietary Variety Score) and DMGFV(Dairy Product, Meat, Grain, Fruit, Vegetable group) were used for assessment of food diversity. A Can-pro 3.0 and an excel were used for dietary data analysis and SPSS 12.0 program was used for statistical analysis. The results were as follows. The NAR of the 9 nutrients was above the RDAs and MAR was $1.71{\pm}0.19$. For 19 days(61.3%), DDS was 5 and for 12 days(38.7%), DDS was 4. The average of DDS was $4.6{\pm}0.25$. The Fruit & vegetable groups were not often served compared to other groups and especially fresh fruit were not given enough. The average of DVS and DVSS were $22.48{\pm}0.61$ and $29.26{\pm}0.66$ each. The most frequent food pattern was 'DMGFV=11111' which was served for 19 days(61.3%) and second frequent pattern 'DMGFV=11101' was served for 12 days(38.7%). DDS was significantly associated with Vit. C intake and DVS and DVSS was significantly related to Vit. $B_1$ and Vit. $B_2$ intakes. The MAR was significantly correlated with only DVSS. It could be interpreted that DVSS is a useful parameter for evaluating nutrient intakes as previous studies verified. Based on these findings, it can be said that military foodservice was provided with adequate nutrition and diversity. Menu was well composed of various foods which met the nutrition standards, but should provide more fresh fruits for adequate provision of vitamins and minerals.