• Korean Journal of Organic Agriculture
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• v.16 no.2
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• pp.219-230
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• 2008

This trial was conducted to assess effects of cattle slurry application on productivity and feed values of barley and hairy vetch when they were influenced by single or mixed-sowed cultivation in paddy fields, and to obtain good quality of organic forage resources. The results summarized are as follows. For barley and hairy vetch, single-sowed cultivation was lower in annual dry matter (DM) and total digestible nutrients (TDN) yields than mixed-sowed (P<0.05). Although crude protein (CP) contents for the barley within single-sowed treatments were lowest as 6.5%, those of hairy vetch within the same sowed method were highest as 16.7%. However, mixed-sowed cultivation with barley and hairy vetch, showing 13.8% CP content, was significantly (P<0.05) higher than CP and relative feed value (RFV) of barley alone treatment. For barley alone treatment, cattle slurry application significantly increased annual DM and TDN yields in comparison with treatments of P+K fertilization as chemical fertilizers and no fertilizer as controls. Results from cattle slurry application showed 84% and 82% in contrast with chemical fertilizer for annual DM and TDN yields, respectively. For mixed-sowed cultivation with barley and hairy vetch, cattle slurry application showed 90% and 94% annual DM and TDN yields, respectively as compared with N+P+K fertilization as chemical fertilizers. Crude protein contents ($14.2{\sim}15.9%$) for cattle slurry application treatments were significantly (P<0.05) higher than those of other treatments. Moreover, cattle slurry application treatment had the highest TDN and RFV among treatments, showing $60.7{\sim}61.8%$ and $112.2{\sim}118.1$, respectively. For hairy vetch alone treatments, annual DM and TDN yields of cattle slurry alone application treatment were highest among fertilization treatments. Furthermore, CP, TDN and RFV of cattle slurry alone application treatments were significantly (P<0.05) higher than those of other treatments. The results showed that mixed-sowed cultivation rather than single-sowed for barley or hairy vetch improved their nutritive value and quality, and also within mixed-sowed cultivation, cattle slurry application increased production yield per ha and CP contents. In the application of above system to organic livestock farming, it would be expected that forages produced by cattle slurry application under mixed-sowed method might become a substitute for foreign organic grain as protein sources.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.4
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• pp.244-251
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• 1991

This study was undertaken to assess the effectiveness of magnesium-and boron-enriched complex fertilizer(CF, N-P$_2$O$_{5}$-K$_2$O-MgO-B$_2$O$_3$: 14-10-12-3-0.2) on the maintenance and management of hilly pasture. The effectiveness of CF was compared to those of some straight fertilizers (SF). This first part of the study was concerned with the soil chemical properties and the mutural balances of mineral nutrients in the soils of a mixed grass-clover and a pure grass swards. The results of a two-year field experiment are summarized as follows: 1. The Mg contents in the soils of the CF plots were higher than those of the SF plots. On the other hand, the Ca contents were higher in the SF plots than in the CF plots. The contents of Mg and Ca, and CEC, except K, in both the CF and SF plots were considerably below the optimum levels. At the normal application rate of NPK, the contents of available P$_2$O$_{5}$ were close to the optimum level in both the CF and SF plots. 2. The contents of exchangeable Mg were lower than the K contents in soils of all the plots. At the normal application rate of NPK, the Mg contents in the CF plots, but not in the SF plots, were close to the critical level for general crops (0.29me Mg/100g soil). The Mg contents in soils of all the plots, however, were considerably below the critical level for pasture forages and grazing cows (0.41me/100g). 3. Considering the desirable base saturation level of soil, the saturation levels of Ca and Mg were insufficient in both the CF and SF plots. The saturation levels of Mg in the CF plots, however, were relatively good compared with the SF plots. The equivalent ratios or Mg/K, Ca/Mg. Ca:Mg:K, and %Mg of CEC in soils were generally unfavorable in all the plots. These ratios of the CF plots, however, were relatively better than those of the SF plots. 4. Considering the contents of exchangeable Ca and Mg in soils, it is suggested that the application of slaked magnesium lime as a soil amelioration might be desirable for the fundamental increment of those contents at pasture establishment.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.3
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• pp.159-170
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• 2006

This study was conducted to investigate the effects of two dry matter levels of liquid swine manure on dry matter yield and nutritive value of Italian ryegrass, rye and oats, and the chemical characteristics of soil in Jeju. This experiment tested in split plot design. Three forage crops (Italian ryegrass, rye and oats) were the main plot and four fertilizers (no fertilizer=T0, chemical fertilizer=T1, liquid swine manure with DM 2.7%=T2 and liquid swine manure with DM 5.9 %=T3) were the sub plots. Yield and nutrient contents of forage crops and soil properties were determined. Application of liquid swine manure containing 5.9% dry matter resulted in highest DM yield in all three forage crops species compared with the other treatments (p<0.01). Crude protein content(%) and crude protein yield(kg/ha) of forage crops were highest in rye compared with the other forage crops species(p<0.01). K and Mg contents of soil were higher(p<0.01) in rye than in the other species while Na contents was higher(p<0.01) in Italian ryegrass than others. Mg content of soil appeared higher in rye than in the others and higher(p<0.05) in forage crops applied with liquid manure containing 2.7% DM compared with the other species. $NO_3-N$ contents in soil was lower in rye than the other species and higher in species with chemical fertilizer. These findings indicate that most of liquid swine manure produced on local pig farms containing low levels of dry matter and other nutrients suggest a low efficiency of its use as a fertilizer. The liquid swine manure is recommended as a fertilizer for rye production in winter, compared with Italian ryegrass or oat.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.4
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• pp.233-238
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• 2006

The experimental work was conducted to determine the growth characteristics, yield and feed value of sorghum-sudangrass hybrid and $NO_{3^-}N$ leaching by application of various types of livestock manure (LM) at National Livestock Research Institute, Suwon, for 3years (2003-3005). The growth characteristics in chemical fertilizer (CF) was better than others in general. The growth characteristic of sorghum-sudangrass hybrid by the various type of LM was good in order of composted swine manure (CSM) > liquid swine manure (LSM) > composted cattle manure (CSM), whereas the growth characteristics by application level of LM was good in order of LM 100%+CF 25%>LM 75%+CF 25%>LM 100%. Dry matter(DM) yield in LSM and CSM increased by 23% and 18% respectively while DM yield in CCM decreased 24% as compared to CF. Moreover total digestible nutrients (TDN) in LSM and CSM increased by 24% and 18% respectively while TDN in CCM decreased 12% as compared to CF. Crude protein and relative feed value in LM decreased compared to those in CF. $NO_{3^-}N$ leaching by application level of LM showed that there was an increase in order of LM 100%+ CF 25%>LM 75%+CF 25%>LM 100%. Also the high concentration of $NO_{3^-}N$ occurred shortly after application of LM.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.2
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• pp.124-130
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• 1986

To find out the optimum split application ratios of fertilizer nitrogen and potassium in the newly opened pasture at spring, a field experiment was conducted. Two levels of nitrogen and potassium application and three split application ratios of both fertilizer were treated by split design with 4 replications. The experiment was carried out from March, 1984 to October, 1985 on the experimental field of the Livestock Experiment Station in Suweon. The results obtained are summarized as follow: 1. Total DM yield was not showed signigicant difference among split application ratios of nitrogen and potassium. 2. DM yield of grasses was 4,854 kg/ha in heavy basal application of N and $K_2$O (160 kgN: 140 kg $K_2$O/ha), it was significantly increased by 16% than of conventional dressing (80 kg N: 70 kg $K_2$O/ha). But there was almost no difference in dry matter among N and $K_2$O split application ratios. 3. Dry matter yield of legume in heavy basal dressing was decreased by 23% than that of conventional dressing. In the methods of NK application, dry matter yield of legume was tended to decrease by 3% with equal application and 9% with heavy dressing in autumn, when compared with that of heavy dressing in spring. 4. There was no significant difference in dry matter yield of native species between different basic fertilization levels, but dry matter yield of native species was decreased by 6% with equal application and more increased by 11% with heavy dressing in autumn, when compared with the yield of heavy dressing in spring. 5. In aspect of the botanical composition, the percentage distribution of grasses was increased and the ratio of legume was greatly decreased by heavy dressing at basal fertilization. Also for good maintenance of botanical composition, it is suggested that the equal split application of N and $K_2$O was desirable.

• Journal of the Korea Concrete Institute
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• v.19 no.1
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• pp.121-130
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• 2007

To investigate the enhancement in strength and deformation capacities of concrete confined by FRP composites, tests under axial loads were carried out on three groups of thirty six short columns in circular section with diverse GFRP confining reinforcement. The major test variables considered include fiber content or orientation, wrap or tube type by varying the end loading condition, and continuous or discontinuous confinement depending on the presence of vortical spices between its two halves. The circumferential FRP strains at failure for different types of confinements were also investigated with emphasis. Various analytical models capable of predicting the ultimate strength and strain of the confined concrete were examined by comparing to observed results. Tests results showed that FRP wraps or tubes provide the substantial increase in strength and deformation, while partial wraps comprising the vertical discontinuities fail in an explosive manner with less increase in strength, particularly in deformation. A bilinear stress-strain response was observed throughout all tests with some variations of strain hardening. The failure hoop strains measured on the FRP surface were less than those obtained from the tensile coupons in all tests with a high degree of variation. In overall, existing predictive equations overestimated ultimate strengths and strains observed in present tests, with a much larger scatter related to the latter. For more accuracy, two simple design- oriented equations correlated with present tests are proposed. The strength equation was derived using the Mohr-Coulomb failure criterion, whereas the strain equation was based on entirely fitting of test data including the unconfined concrete strength as one of governing factors.

• Journal of The Korean Association For Science Education
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• v.38 no.3
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• pp.305-317
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• 2018

In this study, we investigated the characteristics of participant students' modeling with the blackbox simulation program and epistemic criteria. For this research, we developed a blackbox simulation program, which is an ill-structured problem situation reflecting the scientific practice. This simulation program is applied in the activities. 23 groups, 89 second year students of an education college participated in this activity. They visualized, modeled, modified, and evaluated their thoughts on internal structure in the blackbox. All of students' activities were recorded and analyzed. As a result, the students' models in blackbox activities were categorized into four types considering their form and function. Model evaluation occurred in group model selection. Epistemic criteria such as empirical coherence, comprehensiveness, analogy, simplicity, and implementation were adapted in model evaluation. The educational implications discussed above are as follows: First, the blackbox simulation activities in which the students participated in this study have educational implications in that they provide a context in which the nature of scientific practice can be experienced explicitly and implicitly by constructing and testing models. Second, from the beginning of the activity, epistemic criteria such as empirical coherence, comprehensiveness, analogy, simplicity, and implementation were not strictly adapted and dynamically flexibly adapted according to the context. Third, the study of epistemic criteria in various contexts as well as in the context of this study will broaden the horizon of understanding the nature of scientific practice. Simulation activity, which is the context of this study, can lead to research related to computational thinking that will be more important in future society. We expect to be able to lead more discussions by furthering this study by elaborating and systematizing its context and method.

• The Journal of the Korean bone and joint tumor society
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• v.11 no.2
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• pp.168-174
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• 2005

Purpose: We experienced 8 cases of osteoid osteoma arising around hip joint which had some characteristics that differ from those arising on long bone. we reports the characteristics of osteoid osteoma arising around the hip joint. Materials and Methods: 8 cases of osteoid osteoma were diagnosed during 1985 to 2004 at hanyang university hospital. all cases were comfirmed patholgically. 6 cases were male, 2 cases were female patients. The mean age was 17 years old (ranged from 8 to 29). They occurred in intertrochanteric area (4 cases), subtrochanteric area (2 cases), acetabulum (1 case) and femoral neck (1 case). We used radiologic tools including magnetic resonance image, computed tomography, bone scintigraphy. clinicopathologic test including erythrocyte sedimentation rate and Creactive protein. Results: The patients expressed various symptoms including thigh pain, knee pain, low back pain and radiating pain respectively. 2 patients had experienced operation on knee joint. 3 patients showed limping gait. Aspirin relieved the pain in 3 patients. The difference in circumference was 1cm between both thighs in 2 cases. Conclusion: Patients with osteoid osteoma arising around hip joint which have various symptoms such as severe knee pain and claudication, differ from infectious disease by clinicopathologic test including erythrocyte sedimentation rate and C- reactive protein and had better diagnostic result in computed tomography.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.1
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• pp.1-9
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• 1999

To find pertinent soil type and maintenance method for artificial planting ground, the effects of soil compositions{sandy loam(S), vermiculite(V), sandy loam+vermiculite+sand(SVS), sandy loam+ carbonized rice husk+sand(SCS), sandy loam+humus sawdust+sand(SHS)}, and fertilizers (organic, chemical) on plant(kentuckyblue grass) growth were measured and compared from the field experiment. The results are summarized as follows 1. the highest germination rate is found from "vermiculite(V)" and the lowest from "sandy loam(S)" among tested 5 soil compositions. 2. "sandy loam+vermiculite+sand(SVS)" composition shows the highest plant height growth effect (5cm growth during tested 3 months) comparing to other 4 compositions. 3. "sandy loam+vermiculite+sand(SYS)" composition shows the highest ground covering rate after first two months, but it concede its order to "sandy loam+humus sawdust+sand(SHS)" composition after next one month growing. 4. the effects of fertilizers are follows 1) Among the blocks where no fertilizer was tried, the predominant height growth was obvious in "sandy loam+carbonized rice husk+sand(SCS)" and "sandy loam+humus sawdust+sand(SHS)" composition. 2) Among the blocks where chemical fertilizer was tried, relatively positive results were found from "vermiculite(V)" and "sandy loam+vermiculite+sand(SYS)" blocks on germination and growth rate. But on the ground coverage ratio, the effect of "sandy loam+carbonized rice husk+sand(SCS)" composite precede that of those 2 composites. 3) Among the blocks where organic fertilizer was tried, "sandy loam+humus sawdust+sand(SHS)" and "vermiculite(V)" blocks show relatively high ground coverage rate, growth rate than others. 4) When compositional differences were not considered, the block where organic fertilizer was tried shows most positive effects on all 3 measurements-germination ratio, height growth and ground covering.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.4
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• pp.254-261
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• 2014

This study was to assess the effect of sowing mixed legume forage and applying cattle manure on the productivity and feed value of whole-crop barley (WCB) as a representative of winter crops and to estimate feeding capacity of Korean native cattle (Hanwoo) per unit area by defining optimal application level of cattle manure for more fertile soil and manure recycling for the purpose of reduced environmental pollution and efficient production of organic forage contributable to production of organic animal products. Sowing mixed legume forage significantly (p<0.05) increased yields of dry matter (DM), crude protein (CP) and total digestible nutrients (TDN) for WCB compared to WCB alone sowing, but there was no difference between mixed sowing treatments. The yields of DM, CP and TDN were significantly (p<0.05) highest in 100~150 kg N/hg. The CP and acid detergent fiber (ADF) contents were highest in mixed sowing with hairy vetch, followed by sowing mixed forage pea and WCB alone (p<0.05). There were no differences in CP and neutral detergent fiber (NDF) contents among cattle manure application levels. As nitrogen application level increased, ADF content increased (p<0.05), but TDN content decreased (p<0.05). Feeding capacity of organic Hanwoo (head/ha) weighing 450 kg of body weight with 400 g of daily gain significantly (p<0.05) increased due to mixed sowing with legume forage, and with increasing application levels of fermented cattle manure, feeding capacity significantly (p<0.05) increased. The results indicate that mixed-sowing of WCB and legume forage not only cut nitrogen application level of fermented cattle manure by over 50 kg per ha but also increased their feed value and productivity, and feeding capacity. This would be contributable to diversity of forage resources as well as production of organic animal product by creating low cost and high quality of forage.