• 한국토양비료학회지
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• 제50권4호
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• pp.259-274
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• 2017

To get some informations for sustainable paddy use, the productivities of soils with two years of cropping systems were estimated through pot experiment using two pretreated groups of not autoclaved 'natural'- and 'autoclaved'-soils without any fertilization. And then the relationship between the productivities, called yield potentials, and the characteristics of soils as affected by cropping systems, such as rice-rice (R-R), ricebarley-rice-barley (R-B-R-B), rice-barley-rice-wheat (R-B-R-W), soybean-barley-soybean-barley (S-B-S-B), of which barley and wheat were composted at a level of $10MT\;ha^{-1}$, and S-B-S-B without compost, was analyzed. These treatments were established in mid-mountainous loam paddy, which contained exchangeable Ca of $11.8cmol_c\;kg^{-1}$, located at the altitude of 285 m above sea level in Sangju of Korea. Crops for the estimation of soil productivity were rice cv. 'Seolemi' and soybean cv. 'Chamol'. As a result, under the natural soils condition, rice grain and straw were highly produced in composted S-B-S-B soils (p < 0.05) and lowly in R-R soils (p < 0.05). While soybean grain and stem were higher in R-R soils (p < 0.05) than other soils which not significantly different each other. In case of autoclaved soils, the yield potentials of rice and soybean were high together in either composted R-B-R-B/W or S-B-S-B soils compared to R-R and uncomposted S-B-S-B soils (p < 0.05). In especial, these yield potentials under the natural soils condition were commonly influenced by soil porosity showing negative correlation for rice (p < 0.01); positive for soybean (p < 0.05). And the porosity possibly reversed even the symbiotic contribution of indigenous Bradyrhizobium japonicum for soybean. Under autoclaved soils condition the potentials of rice and soybean showed negative correlations with soil C:N ratio (p < 0.05) similarly to the case of rice in the natural soils.

• Bulletin of the Korean Chemical Society
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• 제29권1호
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• pp.85-88
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• 2008

A direct application of the WKB quantization to the three-dimensional Coulomb potential does not yield the exact eigenenergies. The three-dimensional Coulomb potential is converted to a Morse potential by using the point canonical transformation. Then the WKB quantization is applied to the Morse potential to find a relationship between the eigenenergies of the Coulomb and those of the Morse potentials. From the relationship the exact eigenenergis of the Coulomb potential are determined. The same method is found to be also valid for the three-dimensional harmonic oscillator potential. And the Langer modified WKB quantization is algebraically derived.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1994년도 춘계 학술대회지
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• pp.150-151
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• 1994

• 한국작물학회지
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• 제46권1호
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• pp.64-67
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• 2001

Snap bean is a new corp in Korea but believed to have a great deal of potentials for both domestic and overseas markets. The present study was performed to obtain the basic information about growth- and quality-related characteristics and to determinate the optimum seeding date and harvesting time for snap bean. Pod yield was significantly affected by seeding date. The highest pod yield was obtained from March 20 for determinate type and April 4 for indeterminate one, respectively, with the range of 13.0-23.7 t/ha. The pod length of indeterminate type was over 13cm, and the pod length was over 5 grams. The pod width for tested varieties was less than 1.0cm. Considering the pod growth characters such as pod length, pod width, and pod weight, the optimum harvesting time for immature pods of snap bean was supposed to be from 15 to 20 days after flowering. The daily yield of snap bean was begun to sharply increase from 15 days after the first flowering and the maximum yield was recorded at 30 days after flowering. For the accumulated yield, nearly 90% of total yield was obtained in 42 days after flowering.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 추계학술대회논문집
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• pp.156-159
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• 2004

Most formulations for a forming limit diagram (FLD) have been based on yield stress potentials defined in the stress field. Nevertheless, there are formulations where potentials defined in the stain-rate field are especially convenient to formulate the rigid plastic material. Based on a strain-rate potential proposed for materials exhibiting planar anisotropic, the formulations for the forming limit diagram has been developed applying M-K theory. As verification example, the formulation is applied for anisotropic AA5182-O sheet. The good verification results show that the formulation for the forming limit diagram has been successfully developed.

• 한국토양비료학회지
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• 제16권2호
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• pp.98-105
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• 1983

토양수분조건에 따른 시비반응을 구명(究明)하기 위하여 본량(本良) 사양토(砂壤土)에서 토양수분처리($M_0$무관수, $M_1$-0.1~-1.0bar, $M_2$-0.1bar~-0.5bar, $M_3$-0.1~-0.2bar)와 시비수준(施肥水準)(N-P-Kkg/10a, 0-0-0, 11.5-10-12.5, 23-20-25, 34.5-30-37.5)을 달리하여 봄배추의 생육상태(生育狀態), 물소모량(消耗量), 양분흡수량, 비료이용율(肥料利用率), 수량 등을 조사(調査)한 결과(結果)는 다음과 같다. 1) 20cm 깊이에서 토양수분 Potential이 -2.0bar 이하(以下)일 때 물소모량은 감소(減少)하였고 비료(肥料)에 의(依)한 생장량(生長量)의 증가는 없었다. 2) 배추의 양분흡수량(養分吸收量)은 시비량(施肥量)의 증가에 따라 토양수분 Potential이 낮을 때는 감소(減少)하는 경향(傾向)이었고, 토양수분 Potential이 높을 때는 증가하는 경향(傾向)이었다. 3) 질소(窒素)와 가리(加里)의 이용율(利用率)은 토양수분 Potential과 시비수준(施肥水準)이 정비례관계(正比例關係)에 있어야 이용율(利用率)이 증대되었다. 4) 봄배추의 수량(收量)은 토양수분 Potential이 낮을 때에는 시비량(施肥量)을 증가시켜도 증수가 없었으며, 토양수분 Potential이 높을 때에는 각(各) 시비수준(施肥水準) 공(共)히 증수효과(增收效果)가 있었고 그 효과(效果)는 다비수준(多肥水準)에서 더욱 뚜렷하였다. 5) 토양수분 Potential을 높게 유지(維持)시킬 경우(境遇)에는, 시비량(施肥量)을 증가시킴에 따라 봄배추 수량(收量)이 거의 직선적(直線的)인 증가경향을 보여, 최대수량을 낼 수 있는 비료요구량(肥料要求量)이 크게 증가되었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.19-19
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• 2017

The indica ${\times}$ japonica rice (Oryza sativa L.) cultivars released in Japan since 1980 are high-yielding. However, occasionally in these cultivars their high yield potentials cannot be realized, particularly depending on climate conditions. The objectives of this study were to identify the reason for yield instability and the critical yield component factor causing lower grain yield in these high-yielding cultivars. Standard-yield japonica, high-yielding japonica-dominant, and indica-dominant cultivars were grown in western Japan. Rough grain yield (RY) in these high-yielding cultivars ranged from 450 to $980g\;m^{-2}$, and was positively correlated with potential grain yield (PRY). By fluctuations of solar radiation, RY changed with spikelet number (SNO), and SNO was correlated with cumulative radiation during the panicle formation period of 30 days before heading. Even if higher SNO was achieved under higher radiant conditions, RY was lower than PRY. The lower grain-filling in plants bearing higher SNO resulted from a lower filling percentage of spikelets (%F, RY/PRY), and %F was strongly correlated with spikelet fertility (%S) across all cultivars. %S was highly influenced by cumulative radiation per PRY during pollen development and establishment around heading. Inhibition of assimilation by leaf removal lowered %S. Conversely, stem thinning and removal of upper panicles around heading increased %S in spikelets of the lower part of the panicle in which sterility was higher. These results suggest that limitation of assimilate-supply due to low irradiance at the spikelet-formation and flowering stages restrains the potential of the high-yielding cultivars, depending on reduction of SNO and %S, respectively.

• 한국작물학회지
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• 제38권4호
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• pp.336-342
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• 1993

1. 개화성기까지의 지상부와 지하부 대부분 생육형질은 전에서 보다 답에서 더 큰값을 보였으나, 근류수는 다에서 현저히 작아 윤환답 콩재배에서는 근류접종이 필요하다고 생각되어 진다. 2. 조파 단작(4월 20일 파종)으로 윤환답에 콩을 재배하면, 만파재배시 양저바이러스(SMV-N)에 저항성을 보였던 대부분 현재의 장려품종들이 심하게 이병되었다. 그러나 경미한 모자이크바이러스(SMV) 이병정도를 보이는 일부 장려품종(장백콩과 은하콩 등)과 대부분의 도입품종들은 양저바이러스에 전연 이병이 되지 않고 대부분 높은 수량성을 보였다. 3. 콩의 토양별 평균 종실수량은 전보다 답에서 높았으나, 동일 토양내의 파종시기 또는 동일 파종기내의 토양간 평균 수종간에는 차이가 없었다. 4. Ha당 4톤 이상의 수량을 보인 품종은 답에서는 Williams79, 남해콩, Union 및 SS77053이었고, 전에서는 Union뿐이었다. 공시품종중 장엽콩과 단엽콩은 답의 모든 파종기에서 종실수량이 ha당 3톤 이상이고 변이계수가 10% 이하로 안정 다수이었다. 5. 답전윤환답의 조파에서 다수성인 품종들은 황금콩에 비하여 경장이 크고 주경전수가 많으며 분지수가 SS77053을 제외하고는 적은 일반적으로 초기발아 및 입묘에 유리한 중소입종들로 내병성, 특히 양저 바이러스에 저항성이 높은것들이었다.

• 한국정밀공학회지
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• 제19권11호
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• pp.37-45
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• 2002

This paper presents the field-dependent Bingham characteristics and damping force control of an electro-rheological (ER) fluid under squeeze mode operation. The squeeze force of the ER fluid due to the imposed electric field is analyzed and an appropriate size of the disk-type electrode is devised. On the basis of the theoretical model of the ER fluid under squeeze mode operation, the yield stress and response speed of the ER fluid are distilled from the time responses of squeeze force to the step electric potentials. Measured squeeze forces under various excitation conditions are compared with the predicted ones from Bingham model and time constant obtained at the transient response test. In addition, the controllability of the field-dependent damping force of the ER fluid under squeeze mode is experimentally demonstrated by implementing simple PID controller.

• 한국방재학회 논문집
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• 제7권1호통권24호
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• pp.67-72
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• 2007

본 연구에서는 토사에 대한 질량보존의 법칙을 이용하여 자연유역 내 토양의 침식 및 퇴적 잠재능을 산정할 수 있는 모델을 개발하였다. 이 프로그램은 각 셀 별 토사에 대한 질량보존의 법칙을 적용하여 GIS환경하에서 구동 가능하도록 구성되어있으며 셀 별 토사발생량은 RUSLE 공식을 이용하여 산정하였다. 토양의 침식 및 퇴적 잠재능은 토사의 유출량과 유입량의 차에 의해 각 셀이 침식되거나 퇴적된다는 질량보존의 법칙을 이용하여 산정하였다. 질량보존의 법칙을 적용하기 위한 셀 별 토사유출량은 토사발생량과 토사전달률을 곱하여 산정하였으며 이 토사 유출량이 흐름방향 알고리즘에 의해 결정되는 하류 셀의 토사유입량이 된다. 본 연구에서 개발된 모델을 이용하여 국내 소유역에 대해 적용하였으며 그 결과를 실측치와 비교함으로써 모델을 검증하였다.