• Korean Journal of Organic Agriculture
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• 제26권1호
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• pp.99-128
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• 2018

The cultivation area of rice as staple grains is decreasing in the domestic situation in Korea. Import volume of a duty in foreign rice is 409,000 tons for a year regardless increasing of production per unit area and decreasing of rice consumption. The total stock of rice is increasing cumulatively despite the effort for production mediation of rice. Therefore, maintenance of cultivation area and reduction of production are necessary for national foodstuffs security problems. Development of environment-friendly and low-carbon technology as alternative of global warming and aging of farm labor power is very important responsibility for descendants with creation of sustainable agriculture environment. As alternative for demand and supply stabilization of rice from all angles, first stage: extension of environment-friendly cultivation area as 17% Jeollanam-do level with maintenance of cultivation area under the present circumstances, second stage: extension of environment-friendly cultivation area as 25%, third stage: extension of environment-friendly cultivation area as 35%. From above mentioned scenario, reduction of rice production (60,000 tons), increases of production cost (59,200,000,000 Won), and reduction of income (201,500,000,000 Won) are estimated in first stage. Reduction of rice production (90,000 tons), increases of production cost (122,100,000,000 Won), and reduction of income (313,700,000,000 Won) are estimated in second stage. Reduction of rice production (380,000 tons), increases of production cost (222,000,000,000 Won), and reduction of income (464,500,000,000 Won) are estimated in third stage. From analysis results for partial tillage in transplanting cultivation complex (10ha), rice production is decreased 1.3~1.5 ton by complex. Production cost of rice is decreased and increases of income cultivation type. Gradual extension of environment-friendly agriculture and low-carbon partial tillage could be expected for environment maintenance of the territorial integrity, confidence of consumer, and high-efficiency of low-cost.

• Journal of agriculture & life science
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• 제50권2호
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• pp.73-82
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• 2016

Best drought tolerance index was determined through statistics analysis and growth appearance of drought tolerant plants was determined by cultivation in pot and sloping land. For determination of best drought tolerant indicators, RD(Resistant dry days), LD(Leaf area), UTR(Unit transpiration), RWC(Relative water content), RWL(Relative water loss), LA(Leaf area), SN(Stoma unmber) and SA(Stoma area) were carried out by correlation and PCA analysis. RWL and UTR were affected on plant drought tolerance according to comparison among six indices for resistant dry days. The PCs axes separated SA, LA, RD and RWC and SN. UTR was negatively correlated with SA, RWL were also negatively correlated with RWC and SN. RWL and UTR were proved best selection indicator for the selection of drought tolerant species. Ulmus parvifolia, Bidens bipinnata, Patrinia villosa, Kummerowia striata, Arundinella hirta, Artemisia gmelini etc. were selected drought tolerant plants. Shoot growth appearance of drought resistant plants was differed pot and sloping land. Shoot growth and leaf number was no significant differences between the pot and sloping land. However, root growth of drought tolerant plants was all the difference between two cultivation. T/R ratio of drought tolerant plants was also found a big difference. T/R ratio of drought tolerant plants in sloping land was lower than that of pot. These results will be served efficiently plant breeding.

• Clinical and Experimental Pediatrics
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• 제49권9호
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• pp.959-965
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• 2006

Purpose : The purpose of this study was to investigate the effect of prophylactic indomethacin on reduction of patent ductus arteriosus(PDA) and intraventricular hemorrhage(IVH) in extremely low birth weight infants(ELBWI). Methods : Retrospective review of 84 ELBWI who were admitted to our neonatal intensive care unit from June 2004 to April 2006 was performed. Patients were divided into prophylactic group(n=28) and control group(n=56), where prophylactic indomethacin were given within 6 hours after birth. Clinical outcomes were compared between these groups. Results : There were no significant differences in gestational age, birth weight, incidence of hemodynamically significant PDA and severe IVH, and mortality between prophylactic group and control group. However, there were more frequent indications for therapeutic indomethacin, higher incidence of intestinal perforation, and longer time to achieve full enteral feeding in prophylactic group than control group. The incidence of other adverse events attributed to indomethacin prophylaxis did not differ between two groups. Conclusions : Prophylactic indomethacin may not prevent hemodynamically significant PDA and severe IVH in ELBWI. On the contrary, it may be associated with increased risk of adverse events. Further efforts should be investigated to decrease PDA and severe IVH in ELBWI.

• Korean Journal of Poultry Science
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• 제35권4호
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• pp.367-373
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• 2009

This experiment was conducted to determine optimum dietary levels of dietary energy and protein for laying performance and egg quality in organic laying hens. In a $2{\times}3$ factorial arrangement, 360 Hy-Line pullets (21 wk of age) were randomly assigned to experimental diets with 2,800, 3,080, and 3,360 kcal of ME/kg of diet, each containing 16 and 18% CP, respectively. Each dietary treatment was replicated 4 times, and feed and water were provided ad libitum. Experimental birds were raised in floor and received 14h of light throughout 52 weeks of experimental period. The birds were observed for feed consumption, egg production, egg weight, egg mass, feed conversion ratio, Haugh unit, shell thickness, and shell color at 30, 50, and 70 wk of age. Egg production, egg weight, and egg mass were higher (P<0.05) in hens receiving diets with 2,800 kcal/kg of ME/kg of feed than those fed diets containing 3,080 and 3,360 kcal of ME/kg of diets. Eggshell breaking strengths were not significantly different among the dietary ME and CP concentrations. Eggshell thickness was higher (P<0.05) in hens receiving diets with 3,360 kcal of ME/kg of feed than those fed diets containing 2,800 and 3,080 kcal of ME/kg of diets at 50 and 70 week. With increasing in dietary energy levels, the concentrations of blood total cholesterol were also significantly increased. Overall, the laying hens fed organic diet of 2,800 kcal ME/kg and 16% CP showed superior egg production than those of other dietary regimens.

• Journal of the Mineralogical Society of Korea
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• 제16권3호
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• pp.223-232
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• 2003

The co-precipitation method is applied to synthesize the cathode material Li[L $i_{x}$M $n_{1-x-y}$C $r_{y}$ ] $O_2$ for lithium rechargeable batteries at $650^{\circ}C$ (CR650) and 8$50^{\circ}C$ (CR850), respectively. Rietveld indices indicate that $R_{wp}$ with respect to $R_{exp}$ ( $R_{wp}$/ $R_{exp}$) are 9.2%/10.1% for CR650 and 15.9%/9.76% for CR850, respectively. $R_{B}$ and S (GofF) shows 10.9%, 8.54% and 1.9, 1.6, respectively. Rietveld structure refinement reveals that layer structure of LiMn $O_2$ (R3m) coexists with lower symmetry of Li[L $i_{1}$3/M $n_{2}$3/] $O_2$ (C2/c) due to superlattice ordering of Li and Mn in metal-transition containing layers. Unit-cell parameters are calculated as a=2.8520(2)$\AA$, c=14.248(2)$\AA$, V=100.40(l)$\AA^3$ for CR650, and a=2.8504(1)$\AA$, c=14.2371(7)$\AA$, V=100.179(8)$\AA^3$ for CR850. Final chemistry is obtained as Li[L $i_{0.35}$M $n_{0.56}$C $r_{0.09}$] $O_2$ (CR650) and Li[L $i_{0.27}$M $n_{0.61}$C $r_{0.13}$] $O_2$ (CR850), respectively.y...y..vely.y...y..

• Korean Journal of Medicinal Crop Science
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• 제1권2호
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• pp.115-119
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• 1993

This study was carried out to determine optimum harvest time of in vitro multiplied tuber Pinellia ternata(Thunb.)Breit from 1990 to 1992. Tuber yield and its related traits were observed with four harvest times. Plant height was 7.2cm at 6 months and 19.3cm at 24 months after planting. The number of tubers per unit area was significantly increased with the passage of growing time after planting$(78\;tubers/m^2)$, those were increased by 2.3 times in 6 months, 5.6 times in 12 months, 13.3 times in 18 months and 20.0 times in 24 months. The tuber sizes(length, width and weight) were highly enlarged during 12 to 18 months after planting compared with before or after this time. There were smaller tubers and lower tuber yields with shorter growing period, while large tubers above 7.1mm and higher yields with longer growing. It was suggested that the optimum harvest time was 18 months after planting, before over wintering rather than next year of spring, 24months after planting.

• Journal of the Mineralogical Society of Korea
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• 제19권1호통권47호
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• pp.15-29
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• 2006

Synthetic Mn-tourmalines (tsilaisite) were obtained by hydrothermal synthesis under the condition of 2 Kbar, $375{\sim}700^{\circ}C$, and 50 day-run-time with complete substitution of Mg in dravite by Mn (Mn%=0, 25, 50, 75, and 100%). They are all 6 samples containing Mn-tourmaline with some amounts of albite, spessartine, rhodocrosite, phlogopite etc, showing different synthetic condition of temperature and Mn composition. Synthetic Mn-tourmalines are of site deficiency in X-site ($0.53{\sim}0.68$) more than that of natural ones (approx. $0.2{\sim}0.3$) and show Mn cations occupying Y-site less than expected with initial experiments, leading to failure in synthesis of end-member tsilaisite. Rietveld structural refinements reveal that $R_{wp}$ ($R_{p}/R_{exp}$) is in the range of 13.35 and 18.62%, $R_{B}$ and S (CofF) are $4.85{\sim}6.25%$ (S-18: 8.57%), $1.31{\sim}1.59$ (S-18: 1.81), respectively. Unit cell parameters (space group R3m, z=3) are ${\alpha}=15.8994\;{\AA}$ and $c=7.1846\;{\AA}$ in average (S-18: ${\alpha}=15.9491\;{\AA},\;c=7.1773\;{\AA}$). Average bond lengths of and are $2.67{\sim}2.69\;{\AA}$ (S-18: $2.65\;{\AA}$) and $2.00{\sim}2.02\;{\AA}$ (S-18: $1.96\;{\AA}$), respectively. Ditrigonality (${\delta}$) are in the range of 0.022 and 0.031 (S-18: 0.061), indicating degrading symmetry with increase of Mn content.

• Korean Journal of Environment and Ecology
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• 제26권3호
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• pp.412-425
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• 2012

This study investigated the actual vegetation and plant community structure of Geumsun valley and Weonjeok valley of Naejangsan(Mt.) National Park to provide the data for park management. As a result of analysis of actual vegetation, Quercus variabilis community(47.3%) and Quercus serrata community(17.0%) are widely distributed but Carpinus tschonoskii community(7.5%) and Zelkova serrata community(6.9%) are distributed in valley forests. Plant communities were divided into 6 communities of Fraxinus mandshurica, Carpinus tschonoskii, Carpinus tschonoskii-Platycarya strobilacea-Zelkova serrata, Zelkova serrata, deciduous broad-leaved mixture(Zelkova serrata-Lindera erythrocarpa-Acer palmatum), and Lindera erythrocarpa-Cornus walteri according to the analysis of TWINSPAN of classification using 20 plots($400m^2$). Geumseon valley is composed of boulder stone area of average slope $20^{\circ}$, and there were distributed Fraxinus mandshurica community of 86 years old, Carpinus tschonoskii community in age from 56 to 79, and Carpinus tschonoskii-Platycarya strobilacea-Zelkova serrata community in age from 48 to 71. Weonjeok valley is composed of boulder stone area of average slope $11^{\circ}$, and there were distributed Zelkova serrata community in age from 52 to 71, deciduous broad-leaved mixture community in age from 49 to 70, and Lindera erythrocarpa-Cornus walteri community in age from 43 to 51. Ecological succession of each community was predicted to maintain same state. The Shannon's species diversity showed from 0.8220(Fraxinus mandshurica community) to 1.3850(Carpinus tschonoskii community) per unit area of $400m^2$.

• Korean Journal of Organic Agriculture
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• 제24권3호
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• pp.525-537
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• 2016

This study was aimed to grow organic forage as a prime requirement for organic Hanwoo cattle production over a period of 3 years (2012~2015) in Gyeongbuk region, Korea through mixed cropping of winter fodder barley with legume and application of fermented cattle manure. The effect of barley-legume mixed cropping and application of different levels of fermented cattle manure was studied on forage productivity of whole-crop barley (WCB) and evaluation of feeding capacity of Korean native cattle (Hanwoo) per unit area. The collected data was analyzed using SAS 9.3 software. Barley-legume mixed cropping increased (P<0.05) yields of dry matter (DM), crude protein (CP) and total digestible nutrients (TDN) as compared to those of sole WCB as monoculture. Similarly, acid detergent fiber (ADF) contents and relative feed value (RFV) were also higher (P<0.05) in barley-legume mixed sowing forage compared with those of sole WCB as monoculture. In case of manure application, yields of DM, CP and TDN were also found (P<0.05) highest in 100~150 kg N/ha. However, varying cattle manure levels did not influence (P>0.05) CP and neutral detergent fiber (NDF) contents. In response to increasing nitrogen application level, ADF content increased (P<0.05) but TDN content and RFV decreased (P<0.05). The Barley-legume mixed sowing and increasing application levels of fermented cattle manure also significantly enhanced (P<0.05) feeding capacity of organic Hanwoo (head/ha) having 450 kg body weight with 400 g of daily gain. Findings of present study indicated that barley-legume biculture not only cut nitrogen application level of fermented cattle manure by over 50 kg per ha but also increased their feed value and productivity of forage as compared to WCB monoculture. This would be contribution to the diversity of forage resources as well as production of organic animal product by creating low cost and high quality organic forage.

• Korean Journal of Poultry Science
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• 제35권1호
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• pp.21-27
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• 2008

This study was conducted to evaluate the effects of mineral and vitamin-enhanced supplementation on egg production, egg quality and concentrations of calcium and phosphorus in serum of spent laying hens. A total of 240 (72-wk-old) Hyline brown commercial hens were used in the current trial for 4 weeks. Dietary treatments included 1) CON (basal diet), 2) ESS1 (basal diet + Egg shell strengthen 0.1%), 3) ESS2 (basal diet + Egg shell strengthen 0.2%) and 4) FESS (basal diet + Fe egg shell strengthen 0.2%). During the overall period, egg production was increased in CON and ESS2 treatments compared with ESS1 treatment (P<0.05). Egg shell breaking strength and final egg shell thickness were significantly higher in ESS2 treatment than CON and FESS treatments (P<0.05). Egg yolk color index was significantly lower in ESS1 treatment than other treatments (P<0.05). Moreover, Haugh unit was significantly lower in ESS1 and FESS treatments than CON treatment (P<0.05). Mineral- and vitaminenhanced supplementation did not affect either egg shell color or calcium and phosphorus concentration in serum. In conclusion, mineral- and vitamin- enhanced supplementations of laying hens diet are helpful in improving egg shell breaking strength and thickness by supplementation of Egg shell strengthener 0.2%.