• Korean Journal of Plant Resources
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• v.26 no.3
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• pp.370-373
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• 2013

Korean ginseng has been used for thousands of years as an important medicinal plant. Lime-Bordeaux mixture (LBM) was made with copper sulfate and quicklime, which was sprayed instead of pesticides in ginseng field. Net photosynthesis ($P_N$) was compared between Treatment and Non-treatment of LBM in 3 Year Old Ginseng. $P_N$ in control plot recorded $2.94{\mu}mol\;(CO_2)\;m^{-2}s^{-1}$ at the first day of experiment, which was similar until the last day of experiment. However, The $P_N$ in LBM recorded $2.23{\mu}mol\;(CO_2)\;m^{-2}s^{-1}$, which was lower than that in control plot. As time goes by, The $P_N$ in LBM was gradually increased up to $3.21{\mu}mol\;(CO_2)\;m^{-2}s^{-1}$ and finally, it was similar with that in control plot at 7th day as a $3.20{\mu}mol\;(CO_2)\;m^{-2}s^{-1})$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.4
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• pp.214-222
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• 1998

These experiments were conducted to investigate water uptake, electrical conductivity, germination percentage, seedling growth, and seedling establishment rate in direct seeding cultivation of rice. The rice seeds of six japonica type varieties were coated with 12 kinds of polymers in a standard concentration of 0.2% using seed coating machine. The water absorption of the polymer-coated seeds under saturation conditions was not different among varieties, and was the highest in kulcel, maltrin, and waterlock on the polymer-coated seeds. The electrical conductivity with waterlock (55.0 $\mu scm^{-1}g^{-1}$) was higher than the control plot (45.6 $\mu scm^{-1}g^{-1}$) and other treatments. The germination of the polymer-coated seeds was 95.9% at control plot, 92.7% at low temperature and 35.7% at high temperature. The total dry weight of seed decreased in the order of low temperature, control plot, and high temperature, and was effective in pvp (polyvinyl pyrrolidone), opadry, and sacrust. The seedling establishment rate in direct seeding cultivation ranged from 74.9 to 81.0% in flooded paddy surface, and ranged from 64.7 to 76.6% in dry paddy. In both cases, it decreased in the order of early, medium and medium-late varieties, but was enhanced in daran 8600, sepirect, and sacrust. According to this study the recommended polymers for direct seeding cultivation of rice are daran 8600, sepirect, and sacrust.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.3
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• pp.259-265
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• 1991

This experiment was carried out to find of shortening degree of plant height and seed yield of sesame by different treatment of fertilizer and regulator application. Treatment of higher yield was compost, foliar spraying of Tachigaren chemicals and pinching + 1. 5 times as much as control application of 3 elements which was nitrogen, phosphate, potassium. Especially, Tachigaren chemicals plot was showed increasing lodging resistance because of shortening stem of 6cm compare with control plot and more 8% than control plot in seed yield. Expectant treatment of seed yield was application of compost 2,000Kg per l0a. Foliar spraying of Tachigaren chemicals at 6 leaves full-open of main stem was expected higher yield as well as shortening stem.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.6
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• pp.845-851
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• 1986

This Paper presents micro-computer simulation programs for a pneumatic control system. The simulation programs have been written in BASIC language which is suitable for 6502CPU with 48KB memory and consist of 11 programs which describe the time response and frequency response of the pneumatic actuation system. This simulation package is stored in 51/4 inch floppy diskette. The user requires no simulation expertise on the part of designer. As the result of using this simulation programs for the pneumatic control system with stabilizing tank, it has shown that the response time of the system using air as working medium takes more time to be settled but relatively stable rather than the system using helium.

• Journal of the Korea Safety Management & Science
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• v.10 no.1
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• pp.191-195
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• 2008

The present study contributes reviewing and suggesting various models for measurement system analysis (MSA). Measurement errors consist of accuracy, linearity, stability, part precision, repeatability and reproducibility (R&R). First, the major content presents split-plot design, and the combination method of crossed and nested design for obtaining gage R&R. Second, we propose $\bar{x}-s$ variable control chart for calculating the gage R&R and number of distinct category. Lastly, investigating the determination of gage performance curve which establishes the control specification propagating calibration uncertainties and measurement errors is described.

• The Korean Journal of Ecology
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• v.19 no.4
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• pp.341-351
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• 1996

In order to elucidate the differences in early successional development among similary aged old-fields having different soil nitrogen (N), caused by the land use history before at abandonment, the response of plant community along an experimental nitrogen gradient (control plot (No), plot NI with 5.8g $N/m^2$, plot N2 with 11.7g $N/m^2$ and plot N3 with 23.3g $N/m^2$) was investigated in a five-year-old abandoned field. Although the N content in soil among treatments was similar at the end of the growing season, N concentrations in plant tissue increased with the amount of N supplied. These results suggest that almost all the N contained in N-enriched soil might be absorbed by plants during the growing season after N supply. Vegetation tended to grow vigorously by nitrogen supply, and the standing biomass increased significantly in plots NI and N2 . Species richness of plants, especially of annuals and perennials, was more reduced than the control plot, and the species diversity was also reduced by N supply. The importance value (IV) of species by N supply differed in each species along the position on the successional sere: Artemisia princeps var. orientalis as the dominant species in this old-field decreased slightly; annuals as the earlier successional species decreased clearly along nitrogen gardients; Erigeron annuals as the earlier successional species and as a strong competitor with Artemisia princeps var. orientalis had the highest IV by small N supply; Miscanthus sinensis and Rubus crataegifolius as the later successional species increased by large N supply. These results suggest that old-fields with high soil N might show the structural and functional characteristics of the earlier successional stages, but community composition in those old-fields might be changed more quickly from the sarlier successional species than the later successional species.

• The Korean Journal of Ecology
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• v.27 no.3
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• pp.155-159
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• 2004

In order to gain a better understanding of how forests participate in the cycling of carbon, effects of nitrogen addition on soil respiration were investigated on the oak forest in Kongju, Korea. Study site was divided into control, treatment f and treatment 2 plots, with 5 replication in each plot. In each replicate of treatment 1 and treatment 2 were fertilized with ammonium nitrate (NH$_4$NO$_3$), 30 g/$m^2$ and 60 g/$m^2$, respectively. Soil respiration, soil temperature, ammonium-N and nitrate-N were measured during the experimental period. Ammonium-N and nitrate-N in Ta were higher than those in control and T$_1$. Ammonium-N and nitrate-N in top-soil and sub-soil decreased sharply in August after bi9 rainfall in July in T$_1$ and T$_2$, however, those in control plot increased. Soil respiration in T$_2$ Plot showed consistently higher than those in control and T$_1$ until the end of July. However, soil respiration was similar among the control, T$_1$ and T$_2$ in mid-August and September The amount of Co$_2$ released from soil respiration in control, T$_1$ and T$_2$ in mid-August was 8.0$\pm$0.4, 9.3$\pm$0.6 and 10.2$\pm$0.5 $\mu$mol$^{-1}$ ㆍm$^{-2}$ ㆍs$^{-1}$ , respectively. However, those in control, T$_1$ and T$_2$in mid-August was 13.0$\pm$0.4, 13.5$\pm$0.5, 13.3$\pm$0.6 $\mu$mol$^{-1}$ ㆍm$^{-2}$ ㆍ$^{-1}$ , respectively. The results suggest that nitrogen addition in this oak forest has a positive effect on soil respiration.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.1
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• pp.53-57
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• 1990

Among the 6 treatment of not topped and suckered, topped and not suckered, hand suckered, maleic hydrazide treated, fatty alcohol treated to normal Hyangcho, and male sterile line, yield and Quality by price was lower at not topped and suckered, topped and not suckered or male sterile line plot. The content of petroleum ether extracts and ash was lower in hand suckered, maleic hydrazide and fatty alcohol plot, but the trends of reducing sugar, nicotine, and pH were in reverse. Reducing sugar was higher, nicotine and pH was lower in maleic hydrazide plot than in hand suckered or fatty alcohol plot. Filling value and combustibility was lower in maleic hydrazide plot than in hand suckered.

• Korean Journal of Organic Agriculture
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• v.23 no.1
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• pp.113-121
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• 2015

This study was conducted to evaluate the effect of crop rotation cultivation on the suppression of garlic white rot caused by Sclerotium cepivorum in the mini plot ($2^*1^*$ 0.5 m). Six crops, soybean, sesame, mung bean, squash, crotalaria and spring onion, were previously transplanted in the mini-plots infested with S. cepivorum before garlics were planted. After cultivation of the previous crops, garlic was sown in the mini-plot. Non-cultivation plots and non-infested plots with white rot pathogen were used as control. The effect of crop rotation cultivation on the suppression of garlic white rot was evaluated by investigating comparatively the disease incidence (the percentage of infected plants) and yields. As a results, infection rate of garlic white rot was recorded lower in the non-infested plot, crotalaria and soybean cultivation than in the plot of the other crop cultivation. Especially when squash was previously cultivated and garlics were planted in 2013, infection rate of garlic white was recorded the highest score. In 2014, the infection rate of garlic white were low in the garlic on soybean, crotalaria and spring onion treatment whereas it was high in squash treatment, as well. In 2013, garlic yield was the highest in no inoculation plot, followed by crotalaria, soybean, no crop cultivation, sesami, mungbean, squash cultivation plot. In 2014, the yield in the plot of crotalaria and soybean was much higher than that in no inoculation plot. Based on above-described results, it is considered that soybean-garlic and crotalaria-garlic cultivation system can be good crop rotation systems to control garlic white rot.

• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.6
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• pp.129-136
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• 2011

To measure effects of surface cover on runoff and sediment discharge reduction using rainfall simulator, four(5 m${\times}$30 m scale) plot experiments were conducted in this study. Surface covers made with straw mat, Polyacrylamide (PAM), chaff, and sawdust were simulated 4 times under 31.1~44.4 mm/hr rainfall intensities. Compared with results from control plot, the time of runoff generation is delayed and outflow volume decreased with surface cover. Effects on runoff reduction of straw mat, PAM, sawdust and chaff ranged 4.7~81.5 % and runoff rate reduced by 6.5~76.1 % respectively, when compared with those from control plot. The percentage of decrease in sediment discharge were 99.7~99.8 % from straw mat+sawdust+PAM plots, 85.9~95.6 % from straw mat+PAM plots, and 98.5~99.4 % from straw mat+chaff+PAM plots. The runoff, sediment discharge, and SS concentration reduction efficiencies of the cover materials were outstanding when compared to control plot. It was analyzed that reduction of runoff and sediment discharge were mainly contributed by decrease in rainfall energy impact and flow velocity and increase of infiltration due to the surface cover materials. The results could be used as a base for the development of best management practices (BMPs) to reduce runoff, sediment discharge from sloping field.