• Journal of Korea Water Resources Association
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• v.37 no.8
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• pp.687-693
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• 2004

The MODFLOW simulated results with varying input parameter values were compared and analyzed. To understand the relative importance of the input parameters, sensitivity analysis was carried out. The amount of sustainable yield was analyzed with respect to the hydraulic conductivity, specific yield, specific storage, aquifer thickness and the distance of the wells from the river. The results of sensitivity analysis showed that inflow from the river and the aquifer storage were sensitive to the specific yield and aquifer thickness. Sustainable yield was sensitive to the hydraulic conductivity and aquifer thickness. The results of this study can be used as a basic information for groundwater development and management plannings considering regional characteristics.

• Plant Resources
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• v.5 no.3
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• pp.196-201
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• 2002

This study was conducted to investigate the relationships between yearly variations of climatic elements and yearly variations of productivity in sesame. In addition, correlation coefficients among yield and yield components were estimated. The data of yield and yield components were investigated for 10 years from 1992 to 2001. The meteorological data gathered at the Yeosu Weather Station for the same period were used to find out the relationships between climatic elements and productivity. Yearly variation of the amount of precipitation in July and September were large with coefficients of variation(c.v.) of 64.59, 92.47%, respectively, but the variation of the average temperature in June and August were relative small. Yield and plant height greatly with c. v. of 26.24, 23.41 %, respectively, 1, 000 grain weights show more or less c.v. of 3.83% and length capsule setting show still less variation. Correlation coefficients between maximun temperature in period of cultivation(from June to September) and yield are positively significant at the level of 5.1 %, respectively. Correlation coefficients amount the plant height, length capsule setting, number of capsules per plant, weight of 1, 000 grains and seed yield were positively significant at the level of 1 %, respectively. Simple linear regression equations by the least square method are estimated for number of capsules per plant(Y$_1$) and the maximun temperature in August(X) as $Y_1$=10.1255+0.1725X, and for yield(Y$_2$) and the maximun temperature in August(X) as $Y_2$=21.6151 + 1.3724X.

• Plant Resources
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• v.6 no.2
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• pp.134-139
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• 2003

This study was conducted to investigate the relationships between yearly variations of meteorological elements and yearly variations of productivity in rice. In addition, correlation coefficients among yield and yield components were used to find out the relationships between meteorological elements and productivity. Yearly variation of the mean air temperature in May was large with coefficients of variation(C.V.) of 25.0%, but the variation of the duration of sunshine in May were relative small. No. of panicles per hill and 1,000 grains wt. of brown rice were great with C.V. of 21.1, 19.7%, respectively, brown rice yield show more or less C.V. of 5.5% and milled rice show still less variation. Correlation coefficients between temperatures in period of cultivation from May and yield were positive correlations. Correlation Coefficients between precipitation in period of cultivation from Sep. to Oct. and yield are positive correlations. Correlation coefficients amount the panicle length, no. of panicles, no. of spikelets, ratio of ripened grains, 1,000 grains wt. of brown rice, milled rice yield, brown rice yield and milled rice yield were positively significant at the level of 1 %, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.3
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• pp.127-132
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• 2006

This experiment was conducted to evaluate the effect of manure and chemical fertilizer on the forage yield and quality of oat at no-tillage. The experimental design was a randomized complete block design. The three treatments were: chemical fertilizer, manure fertilizer, and chemical and manure mixture. Seedling vigor was higher at chemical fertilizer than manure, but more greener at manure application than chemical fertilizer. Dry matter (DM) content of oat at manure was higher than chemical and mixture fertilizer (p<0.05). There was no difference in DM yield, TDN (total digestible nutrients) yield, and CP (crude protein) yield of oat at no-tillage system, but the fresh yield was significantly higher in chemical fertilizer compared to manure. The CP content for oat was significantly higher in manure than chemical fertilizer. However, no significant effects were observed for NDF (neutral detergent fiber), ADF (acid detergent fiber), TDN and RFV (relative feed value) in different fertilizer application. Based on the results of this study, manure don't affected forage production and quality of no-till oat except CP content because forage oat is used off-season crop.

• Journal of Plant Biotechnology
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• v.39 no.3
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• pp.154-162
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• 2012

This study was conducted to evaluate agronomic characteristics such as growth, quality, and yields of StMyb1R-1 transgenic potato and also to obtain the basic data for establishing assessment guidelines of transgenic potato. Three transgenic lines (Myb 1, Myb 2, and Myb 8) were cultivated under conventional irrigation, drought condition, and severe drought condition and were analyzed by comparing with wild type, non-transgenic cv. Superior. Myb 2 showed a different flower color from wild type and Myb 1 had much bigger secondary leaflets than wild type. Myb 1 and Myb 2 showed higher $P_2O_5$ content in both top and root zone and longer shaped tubers than wild type. In yield factors, transgenic lines had more tubers than wild type, however their yield decreases were severe because of the poor enlargement of tuber under water deficit condition. This tendency was noticeable in Myb 1 and Myb 2. In TR ratio, chlorophyll content, dry matter rate, and relative water content, there were no big differences between transgenic lines and wild type. Meanwhile, in phenotype, growth, quality, and yield factors, substantial equivalent was confirmed between Myb 8 and wild type. Then, Myb 8 showed the highest marketable tuber yield under conventional irrigation, while showed lower level than wild type under water deficit. Judged by this result, the enhancing droughttolerance by StMyb1R-1 gene might actually not mean the enhancement of photosynthesis or starch accumulation in tuber and, furthermore, not the yield improvement. More detailed research will be required to accurately understand the relationship between StMyb1R-1 and yield factors.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.11
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• pp.142-149
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• 2003

Domain switching effect on crack growth in ferroelectric ceramics under combined electric and mechanical loading is investigated. The shape and size of the switching zone is shown to depend strongly on the relative magnitude between the applied electric field and stress field as well as on the ratio of the coercive electric field to the yield electric field. The toughening mechanism is thought to be ferroelectric domain switching leading to the development of a process zone around the crack. Crack-tip stress intensity factor induced by domain switching for the steady state crack growth is numerically obtained.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.820-823
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• 2002

The asymptotic problem of a semi-infinite conducting crack parallel to the poling direction in ferroelectric ceramics subjected to electric fields is analyzed. The main mechanism for the conducting crack growth behavior is thought to be ferroelectric domain switching leading to the development of a process zone around the crack. The shape and size of the switching zone is shown to depend strongly on the relative magnitude on the ratio of the coercive electric field to the yield electric field. It is shown that the crack growth can be either enhanced or retarded depending on the ratio of the coercive electric field to yield electric field.

• Journal of Plant Biology
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• v.19 no.2
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• pp.37-40
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• 1976

The experiment designed to obtain information relative to the favourable levels to apply N.P.K fertilizer was conducted at the hop garden of College of Agriculture, S.N.U. in 1975. The varieties used were 1-year-old Cascade, Hallertau and Shinshuwase. The design of the experiment was a split plot design with 3 replications. Yields were recorded as fresh weight of harvested cones in gram per split plot. The results obtained from the experiment were as follows: 1. The results from analysis of the data for 3 varieties indicated that significant increase in yield were found due to the application of 46g N, 20g P2O5 and 60kg K2O per plant, although higher level thn the above caused a remarkable reduction of yield. 2. The individual fresh weight of harvested cones was significantly increased with application of nitrogen, phosphorus and potash, regardless of fertilizer levels. 3. Analysis of variance for yields showed that there were no significant interaction between fertilizer level and variety, i.e., all varieties used might require the same fertilizer level.

• Journal of Plant Biology
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• v.18 no.2
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• pp.45-52
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• 1975

Effects of air pollutants on vegetation were reviewed and discussed with special reference to sulfur dioxide. Main contents were on the sources, meteorological factors, injury symptoms, relative sensitivity, growth/yield, indicator/diagnosis, combined effects, injury mechanism and effects on plant metabolism, injury diminishing measures, and future research needs.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.4
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• pp.226-231
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• 1992

This experiment was carried out to estimate the dry matter accumulation using growth analysis in spring growth of perennial ryegrass varieties grown under space planting conditions, based on the data of previous paper9'. The results obtained were as follows: 1. Growth parameters of leaf area ratio(LAR), specific leaf area(SLA) and leaf weight ratio(LWR) were recognized siginificant differences between varieties. But, specific leaf area(SLA), leaf weight ratio (LWR) and relative tiller appearance rate(RTAR) were recognized significant differences between growth stages. Specific leaf area(SLA) was significant difference for the interaction of variety Xgrowth stage. 2. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlations with relative growth rate of shoot(RGR) and root(RWGR), and net assimilation rate(NAR) as affected by the varieties and growth stages. 3. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlation with nct assimilation rate(NAR) in all varieties. Leaf area ratio(LAR) had significantly positive correlation with specific leaf area(SLA) in all varieties, but shows a significant negative correlation with leaf weight ratio(LWR) of Maprima variety. 4. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlations with the absolute growth rates of yield components.