• Journal of Korean Society of Forest Science
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• v.57 no.1
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• pp.45-51
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• 1982

The environmental influence on cone crop of Pinus koraiensis has been studied by means of correlation and regression analysis of number of 1-year-old cone and meteorological data. A positive effect on cone crop is brought about by low air temperature during the year of flower bud differentiation and much sunshine duration for the year and the winter before flower bud differentiation. The weather of June before flower bud differentiation is very important for cone production.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.197-200
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• 1999

In order to get abundant germplasm for develop- ing new corn varieties, major morphological characteristics of ear were evaluated with a total of 210 Korean indigenous maize lines collected from various parts of Pusan City and Kyungnam Province, Korea. The ear shape of Korean indigenous maize was mainly cone type or similar to cone type. Cylinder type or similar to cylinder type of corn was collected from the north-west mountainous. region of Kyungnam Province, whereas cone type or similar to cone type was collected from the plain region. In the kernel colors of each ear, ears with mono colored kernels were 55.7% of the total, and ears with two to four mixed colors were 44.3%. Among the mono colored ears, brown was the most abundant at 16.8%. There was an average of 12∼14 rows per ear. Kernal rows per ear varied from 8∼20. Waxy corn was predominant at 67.2%, mixed corn with waxy kernel and common kernel at 11.0%, and common corn at 21.8%.

• Journal of Biosystems Engineering
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• v.6 no.1
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• pp.48-59
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• 1981

The major limiting factor on the determination of combine capacity is the frequent occurence of clogging over the some parts of machine when the crop is wet in the case of Japanese self-feeding type combine. And in the case of American conventional combine having big separating parts, the great grain loss and damage occur when the machine is used for rice harvesting. This experiment was carried out to develop the new type threshing and separating equipment. Proto-type thresher which consist of a conical threshing drum and a conical separating sieve rotating around the threshing cone was constructed and tested. In the case of 800 rpm of threshing cone speed, average threshing loss was below 1 percent, separating loss was about 1 percent, grain damage was about 0.4 percent, and average total power required was about 2.6 PS. This design has some problems such as higher power required or wrapping problems under the conditions of feeding long damp straw. But, compared with the conventional combine or thresher, this machine certainly has some potentials for this approach to combine development. The crop feed rate must be increased through improvement of the feeding portion of the threshing cone. And it is required to investigate further about some parameters causing wrapping phenomena.

• Journal of Biosystems Engineering
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• v.20 no.4
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• pp.313-322
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• 1995

This study was conducted to find the design factors of spraying device of the boom sprayer for low volume application. Specific objectives of this study were 1) to select proper nozzles for broadcast spraying and row crop spraying by the nozzle spray characterisic experiment, and 2) to investigate the coverage characteristic of rice plant at the row crop spraying. The results of this study are summarized as follows. (1) From the tested results on the droplet diameter spectrum and spray pattern the standard flat-fan nozzle and drift guard nozzle were judged as appropriate for the broadcasting. Even flat-fan nozzle showed similar span values to standard flat-fan nozzles and drift guard nozzle : however, the nozzles were found to be inappropriate for broadcasting because of their spray pattern. Hollow cone nozzle showed relatively small span values and uniform spray pattern. (2) For the upper and lower sides of the rice plants, coverage rates of even flat-fan nozzles and hollow cone nozzles were maximum at the second row, but decreased rapidly after the third row. For the middle side of the rice plants, coverage rates of them were maximum at the first row, but decreased rapidly. When one nozzle was tested, C.V. values were in the range of 90~160% and 60~160% on entire heights of rice plant for even flat-fan nozzles and hollow cone nozzles respectively. C.V. values at other parts were poor. Spray coverage rate at the middle part was improved by overlapping the nozzles whereas there was little difference on the upper and lower part of rice plants. (3) For spraying lower part of rice plant between rows, even flat-fan nozzles and hollow cone nozzle were judged as appropriate, but in order to ensure the uniform coverage, distance between nozzles, recommended to be less than 90cm.

• Proceedings of the Korean Society of Crop Science Conference
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• 1988.07a
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• pp.50-51
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• 1988

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.2
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• pp.157-160
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• 1988

This studies were conducted to obtain the basic information for the influencial plant age and cultural altitude in change of hop cone yield in Hoeongseong, Korea. The fresh cone yields per 10a were increased by the increase of plant age showing 181.0 kg in 1-year-old, 516.0 kg in 2-year-old, 670.0 kg in 3-year-old, 726.4 kg in 4-year-old and 761.0 kg in 5-year-old. The productivity of fresh cone at each plant age was significantly different from 1 age to 3 age but the productivity over 4-year-old hop plant was not significantly different. In the average hop cone yields, yearly variation was significant, but the yields among the altitudes studied were not significantly different.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.2
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• pp.141-146
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• 1982

In the vine training methods, main vine training yield was 36% higher than the non-training. Main vine training date was studied for increasing cone yield in hops. Training was done four different dates from May 14 to May 29 including non-training as a check. Earlier training increased cone yield from 12 to 43% due to more beared branches per plant, longer branch length caused by accelerating the branch growth, and an increased of number of cone per beared branch and total cone number.

• Agricultural and Biosystems Engineering
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• v.5 no.1
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• pp.10-20
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• 2004

Precision agriculture aims to minimize costs and environmental damage caused by agriculture and to maximize crop yield and profitability, based on information collected at within-field locations. In this process, quantification of soil physical properties, including soil strength, would be useful. To quantify and manage variability in soil strength, there is need for a strength sensor that can take measurements continuously while traveling across the field. In this paper, preliminary analyses were conducted using two datasets available with current technology, (1) cone penetrometer readings collected at different compaction levels and for different soil textures and (2) tillage draft (TD) collected from an entire field. The objective was to provide information useful for design of an on-the-go soil strength profile sensor and for interpretation of sensor test results. Analysis of cone index (CI) profiles led to the selection of a 0.5-m design sensing depth, 10-MPa maximum expected soil strength, and 0.1-MPa sensing resolution. Compaction level, depth, texture, and water content of the soil all affected CI. The effects of these interacting factors on data obtained with the soil strength sensor should be investigated through experiments. Spatial analyses of CI and TD indicated that the on-the-go soil strength sensor should acquire high spatial-resolution, high-frequency ($\ge$ 4 Hz) measurements to capture within-field spatial variability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.1
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• pp.1-8
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• 1986

Authors investigatigated the analysis heavy metals in corps at the Mankyung river area. Samples were digested with Cone. nitric acid and Cone. hydroc hrorico acid and analyzed by Varian 875 Atomic Absorption Atomic Absorption Spectrophotometer in 1984. The results were as follows: The contents of heavy metals in rice were in the range of $0.41{\sim}5.15,\;1.12{\sim}5.18,\;10.65{\sim}14.54,\;24.15{\sim}35.41ppm$ for Pb, Cu, Mn, Zn respectively. Those in barley were in the range of $0.48{\sim}0.8,\;1.39{\sim}2.81,\;9.69{\sim}14.89,\;30.14{\sim}34.84ppm$ for Pb, Cu, Mn, Zn respectively. Those in kidney bean were in the range of $0.06{\sim}0.13,\;3.65{\sim}6.25,\;.65{\sim}12.15,\;51.25{\sim}65.69\;ppm$ for Pb, Cu, Mn, Zn respectively. Those in corn were in the range of $0.59{\sim}0.89,\;2.15{\sim}2.83,\;6.01{\sim}10.15,\;29.31{\sim}36.15ppm$for Pb, Cu, Mn, Zn respectively. We might be concluded that the above values of heavy metals contained in crop at the sites near to Mankyung river were serious partially.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.3
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• pp.215-221
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• 1988

The hop yield prediction model developed based on meteorological elements in Hoeongseong was Y=6,042.846-17.665 $X_1$-0.919 $X_2$-96.538 $X_3$-138.105 $X_4$＋86.910 $X_{5}$ ＋ $X_{6}$ with MS $E_{p}$ of 25.258, $R_{p}$$^{2}$ of 0.9991, R $a_{p}$$^{2}$ of 0.9962 and $C_{p}$ of 7.00. The minimum air temperature at early growing stage ( $X_1$), the total precipitation at cone ripening stage ( $X_2$), the maximum air temperature at flower bud differentiation stage ( $X_3$) and the maximum air temperature at flowering stage ( $X_4$) influenced on hop yield as decrement weather elements. The average air temperature at early growing stage ( $X_{5}$ ) and the total sunshine hours at cone development stage ( $X_{6}$ ) influenced on hop yield as increment weather elements.lements.