• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.4
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• pp.312-318
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• 2010

This study was carried out to develop and test a prototype program that recommends the nitrogen topdressing rate using the color digital camera image taken from rice field at panicle initiation stage (PIS). This program comprises four models to estimate shoot N content (PNup) by color digital image analysis, shoot N accumulation from PIS to maturity (PHNup), yield, and protein content of rice. The models were formulated using data set from N rate experiments in 2008. PNup was found to be estimated by non-linear regression model using canopy cover and normalized green values calculated from color digital image analysis as predictor variables. PHNup could be predicted by quadratic regression model from PNup and N fertilization rate at panicle initiation stage with $R^2$ of 0.923. Yield and protein content of rice could also be predicted by quadratic regression models using PNup and PHNup as predictor variables with $R^2$ of 0.859 and 0.804, respectively. The performance of the program integrating the above models to recommend N topdressing rate at PIS was field-tested in 2009. N topdressing rate prescribed for the target protein content of 6.0% by the program were lower by about 30% compared to the fixed rate of 30% that is recommended conventionally as the split application rate of N fertilizer at PIS, while rice yield in the plots top-dressed with the prescribed N rate were not different from those of the plots top-dressed with the fixed N rates of 30% and showed a little lower or similar protein content of rice as well. And coefficients of variation in rice yield and quality parameters were reduced substantially by the prescribed N topdressing. These results indicate that the N rate recommendation using the analysis of color digital camera image is promising to be applied for precise management of N fertilization. However, for the universal and practical application the component models of the program are needed to be improved so as to be applicable to the diverse edaphic and climatic condition.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.9
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• pp.2172-2180
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• 1993

Under general loadings, including body forces, crack-face tractions and thermal loading, the energy release rate equation for a two-dimensional cracked body is presented. Defining the virtual crack extension as the variation of the geometry, the equation is directly derived by a shape design sensitivity of the potential energy. Although the form of the derived energy release rate equation is different from other researchers's results, the three example show that the former is exactly the same as the latter. However, the final integral equation do not involve the derivative of the displacement on the crack surface and crack tip region, thereby improving the numerical accuracy in the computation of the energy relase rate. Moreover, as it was derived from the governing equation including non-linear elasticity without special assumptions, the energy release rate of a elasto-plastic fracture can be obtained and any numerical stress analysis method can be applied.

• Structural Engineering and Mechanics
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• v.50 no.5
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• pp.665-677
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• 2014

A numerical method, using a special mixed finite element associated with the virtual crack extension technique, has been developed to evaluate the energy release rate for kinking cracks. The element is two dimensional 7-node mixed finite element with 5 displacement nodes and 2 stress nodes. The mixed finite element ensures the continuity of stress and displacement vectors on the coherent part and the free edge effect. This element has been formulated starting from a parent element in a natural plane with the aim to model different types of cracks with various orientations. Example problems with kinking cracks in a homogeneous material and bimaterial are presented to assess the computational accuracies.

• Korean journal of applied entomology
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• v.58 no.4
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• pp.281-282
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• 2019

We have developed a composition containing three kinds of plant extracts (Deris, Citronella, and Cinnamon) and supplements (xanthan gum and silicone-based compounds) having high control effects on Metcalfa pruinosa. This composition had more than 90% of the nymph bug control effect in the ginseng plantation. In addition, since the insecticidal rate is high for other absorptive pests, it is considered that it can be used as a countermeasure against the implementation of the PLS (positive list system).

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.5
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• pp.286-290
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• 2003

The effect of thinned fruits, apple, pear and peach, on the mycelial growth of mushrooms was investigated. The growth of mycelia with the addition of thinned fruit was clearly better than that in the control for all the tested mushrooms. The growth rate of Pleurotus ostreatus was faster than any other mushroom. The optimal concentrations of thinned apple, pear, and peach in a solid culture were 1.0%, 1.0%, and 3%, respectively, while in a liquid culture the optimal concentrations were 5,0%, 3.0%, and 5.0%, respectively. When Pleurotus ostreatus was incubated in a 20-L pilot scale fermenter with 10 L of a liquid medium containing 3% thinned fruit at 25$^{\circ}C$ and 6 vvm for 10 days, the mass-production of mycelia was 74.2 g/10 L (apple), 96.2 g/10 L (pear), and 86.3 g/10 L (peach). The mycelial yield of Pleurotus ostreatus in a medium containing thinned fruit was 2 ∼ 3 times higher than that in the control.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.6-8
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• 2011

In order to produce the organic foods in accord with international standard, organic seeds should be used in organic farming. This study was conducted to establish the stable production of organic seed of waxy com by examining the growing characteristics, seed yield, and the economy for seed production by organic farming. The optimal sowing timing for organic seed production of waxy com hybrid was within 10 days of the $1^{st}$ of May with yield of 88~90% of conventional seed production. The optimal planting density was 41,600 plants/ha ($80{\times}30$ cm) for organic seed production of waxy com. The weight of 100 seeds and seed productivity increased at the planting ratio of 2:1 mother plant:male plant. Growth and seed production were improved by removing male plant at 7~10 days after silking. Organic fertilizer (mixed oil cake) was applied at a rate of 4~6 Mg/ha before sowing. Black plastic mulching was used for weed control. In addition, sex pheromone trap and bio-control agents were used for safe pest control and low labour cost.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.203-205
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• 2011

Investigation on oriental melon was carried out for 30 minutes starting at 7 PM every day from March 21 to May 24 to find out the effect of light emitting diode on seedling quality, grafting, growth and flowering of oriental melon. According to the result of the investigation, plant height was longer in Blue, Infrared, Red+Blue and Red treatment and leaf number was higher in Blue, Red+Blue and Infrared treatment than those of control. No big difference was identified between control and Yellow, Green, Ultraviolet treatments. Grafting rate was high in Green, Red+Blue and Green treatment. The number of flower every week in control was nine, the number was almost 1 higher in White and Ultraviolet A treatments, but it was 1 to 4 lower in the rest of treatments. The number of female flowers of control was 10, however, it was 21 in Infrared treatment, 17 in White, 15 in Ultraviolet, 13 in Red+lnfrared, 12 in Blue and Red+Blue, 11 in Yellow and 8 in Green.

• International Journal of Industrial Entomology and Biomaterials
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• v.26 no.1
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• pp.61-66
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• 2013

Baculum elongatum has several peculiarities such as parthenogenesis, unique external features, changing body color, and dropping oviposition, which makes it a potential economically useful insect. Oviposition was performed by females without fertilization by the sperm of males. The oviposition period was $42.2{\pm}22.7$ days and the number of eggs per female was $109.5{\pm}70.5$ eggs. The hatch rate was 73.3% at $25^{\circ}C$ and 66.7% after low temperature treatment ($8^{\circ}C$ for 60 days). In nature, B. elongatum overwinters as an egg, but it can be assumed from the results that cold temperatures were not required for hatching. The hatch rate was 98.2% in the treatment using floral foam, fermented sawdust, and leaves. The developmental period was $100.9{\pm}4.2$ days for eggs, $55.3{\pm}4.6$ days for nymphs, and $49.7{\pm}16.0$ days for adults. The length of the eggs was $0.33{\pm}0.0$ cm and the lengths of the nymphs were clearly distinguishable according to the instar stage. Clover(Trifolium repens) was an excellent diet as it was similar to the host plant and could be used as an alternative diet. The rate of reaching adulthood for the insects was 66.7% on an artificial diet containing 25% acacia leaves. For sustainable mass rearing of nymphs or adults of B. elongatum, a natural diet could be used such as acacia (Robinia pseudoacacia), white oak (Quercus aliena), chestnut (Castanea crenata var. dulcis), and bush clover (Lespedeza bicolor), or an alternative diet such as clover or artificial diet.

• Journal of Digital Contents Society
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• v.18 no.1
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• pp.141-147
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• 2017

Scalable extension of High Efficiency Video Coding (SHVC) standard uses the up-sampled residual data from the base layer to make a residual data in the enhancement layer. This paper describes an efficient algorithm for improving coding gain by using the filtered residual signal of base layer in the Scalable extension of High Efficiency Video Coding (SHVC). The proposed adaptive filter selection mechanism uses the smoothing and sharpening filters to enhance the quality of inter-layer prediction. Based on two filters and the existing up-sampling filter, a rate-distortion (RD)-cost fuction-based competitive scheme is proposed to get better quality of video. Experimental results showed that average BD-rate gains of 1.5%, 2.1%, and 1.7% for Y, U and V components, respectively, were achieved, compared with SHVC reference software 5.0, which is based on HEVC reference model (HM) 13.

• Research in Plant Disease
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• v.21 no.2
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• pp.89-93
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• 2015

This study was carried out to develop the economic thresholds for the control of bacterial spot of red pepper. The correlation between diseased leaf rate and yield in field was Y=-0.724X+281.58, $R^2=0.78$, $r=-0.88^{**}$. The correlation between diseased leaf rate and yield loss in field was Y=0.813X+15.95, $R^2=0.78$, $r=0.88^*$.We found that control thresholds was below 30.3% diseased leaves rate per plant in field. The economic control thresholds for bacterial spot of red pepper was below 16.3%.