• 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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.303-313
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• 2020

Rice grain shape is one of the key components of grain yield and market value. An understanding of the genetic basis of the variation in grain shape could be used to improve grain shape. In this study, we developed a total of 265 F₂ individuals derived from a cross between japonica cultivars (Josaeng-jado and Langi) and used this population for quantitative trait locus (QLT) analysis. Correlation analysis was performed to identify relationships between grain traits (GL: grain length, GW: grain width, L/W: ratio of length to width, TGW: 1,000 grain weight). The grain shape was positively correlated with GL and TGW, and negatively correlated with GW. In QTL analysis associated with grain shape, one QTL for GL, qGL5, detected on chromosome 5, explained 20.3% of the phenotypic variation (PV), while two QTLs, qGW5 (PV=36.1) and qGW7 (PV=26.1), for GW were identified on chromosomes 5 and 7, respectively. Evaluation of the effects of each of the QTLs on the grain shape in the population showed a significant difference in the grain size in positive lines compared with the lines without the QTLs. According to the QTL combination of the allelic-types, the grain shape of the tested lines varied from semi-round type to long spindle-shaped type. The results of this study extend our knowledge about the genetic pool governing the diversity of grain shape in japonica cultivars and could be used to improve the grain shape of this species through marker-assisted selective breeding in Korea.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.4
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• pp.295-300
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• 2008

This experiment was conducted to compare forage production and feed value of winter forage crops at the experimental field of Livestock Division, National Institute of Animal Science from 2003 to 2004 in Jeju. The experiment was arranged in slit plot design with three replications. Main plots consisted of two cutting times, one time cutting and two times cutting. Sub plots consisted of 5 different seed combinations, T1 (Italian ryegrass), T2 (Oat), T3 (Italian ryegrass 25+Oat 75%), T4 (Italian ryegrass 50+Oat 50%), T5 (Italian ryegrass 75+Oat 25%). One time cutting showed the highest dry matter (DM) yield by 18,680 kg/ha. Tow times cutting showed the highest crude protein (CP) content by 11.97%. The all treatments have narrow range of total digestible nutrient (TDN) from 60.6% to 70.4%.

• Korean journal of food and cookery science
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• v.26 no.1
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• pp.18-25
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• 2010

This study was carried out to investigate the total polyphenol and flavonoid contents and antioxidative activities of enzymatic digests from dried Citrus unshiu and C. grandis peels. The yields of digests from dried C. unshiu and C. grandis peels were high in viscozyme (a carbohydrase) and kojizyme (a protease), and enzymatic digests from dried C. grandis peels appeared highly comparable to those of C. unshiu. Total polyphenol contents were high in ultaflo (a carbohydrase) and alcalase and flavourzyme (proteases), and the digests from dried C. unshiu peels appeared high in comparison to C. grandis. Total flavonoid contents were high in ultaflo, alcalase, and water extract. DPPH radical scavenging activities appeared very high in digests from dried C. grandis peels in comparison to C. unshiu, and was the highest in viscozyme and kojizyme. The viscozyme digest displayed particularly high activity. Hydrogen peroxide scavenging activities increased somewhat with increasing amounts of digests, but displayed very high activity, more than 91%, except kojizyme the digest from dried C. unshiu peel, at 2.0 mg/mL. Alkyl radical scavenging activities increased rapidly with increasing amounts of digest, and all enzyme digests from dried C. unshiu and C. grandis peels displayed very high activities at more than 0.5 mg/mL. Hydroxyl radical scavenging activities increased rapidly with increasing amounts of digests, and all enzymatic digests from dried C. unshiu and C. grandis peels displayed relatively low activities in comparison to other activated oxygen species.

• Korean journal of food and cookery science
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• v.26 no.1
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• pp.88-94
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• 2010

This study was carried out to investigate the total polyphenol and flavonoid contents and antioxidative activities of the methanol extracts of Citrus sunki, C. unshiu and C. natsudaidai peels before and after drying. Total polyphenolic content was high in the citrus peels before drying compared to the dried peels, and highest in the order of C. sunki, C. natsudaidai and C. unchiu. On the other hand, flavonoid content was high in the dried citrus peels than in the citrus peels before drying, and was highest in the order of C. unshiu, C. natsudaidai, C. sunki, but in dried peels it was highest in the order of C. natsudaidai, C. unshiu, C. sunki. DPPH radical scavenging activity was highest in the order of C. natsudaidai, C. unchiu, C. sunki, and that in the citrus peels before drying was higher than in the dried peels. Inparticular, C. natsudaidai peels before drying showed higher activity than vitamin C in 0.5 or 1.0 mg/100 g. Hydrogen peroxide scavenging activity was highest in the order of C. unshiu, C. natsudaidai, and C. sunki in the citrus peels before drying. The dried peels were highest in the order of C. unshiu, C. natsudaidai, C. sunki at 0.5 mg/100 g, but high in order of C. natsudaidai, C. unshiu and C. sunki at more than 1.0 mg/100 g. Inparticular, all C. natsudaidai peels displayed high activity more than 87% at 2.0 mg/100 g. Clear patterns in alkyl radical scavenging activity could not be confirmed in Citrus species whether before or after drying of peels. Hydroxyl radical scavenging activity was highest in the order of C. natsudaidai, C. unshiu and C. sunki but was relatively low compared to the scavenging activity of other activated oxygen species.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.2
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• pp.127-134
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• 2010

A study was conducted to determine the effects the of cattle manure application on forage yield, quality and soil in orchard grass pasture at the experimental field of Subtropical Animal Experiment Station, National Institute of Animal Science from 2008 to 2009. The experiment was arranged in a randomized complete block design with three replications. The treatment consisted of chemical fertilizer (CF N-200 kg/ha), cattle manure 50% (basis N, CM50%), CM100% (basis N), CM200% (basis N). The dry matter (DM) yield of CM200% was the highest among the other treatments. CF showed the highest average crude protein (CP) content by 12.4% and CM50% showed the lowest content by 11.0%. Average acid detergent fiber (ADF) and neutral detergent fiber (NDF) content were 30.4 and 69.7% respectively. All treatments have narrow range of total digestibility nutrient (TDN) from 64.0% to 69.1%. But there were big difference between treatment in forage nitrate content. Changes of physical and chemical properties of soils for applications of CF 200% and CM 200% was clearly in cattle manure application. Especially, CM application in pasture increased CF application with respect to soil pH, organic matter (OM), and avaliable phosphorous ($P_2O_5$) contents of soils.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.2
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• pp.151-158
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• 2010

This study was conducted to evaluate the feed value and growth characteristics of Sasa quelpaertensis Nakai by horse grazing in the woodland of Jeju. Crude protein (CP), NDF, ADF and minerals contents at different growth stages of Sasa quelpaertensis were analyzed. The apparent digestibilities of DM, CP, NDF and ADF were determined by total collection method using 5 Jeju horses. The yield and growth characteristics of S. quelpaertensis Nakai by horse grazing were investigated. CP contents in the currentand the previous-year-sprouted leaves of S. quelpaertenisis were $16.6{\pm}1.0%$ and $12.2{\pm}1.1%$, respectively. The digestibility of DM, CP, NDF and ADF in the current-year-sprouted leaves of S. quelpaertenisis were $47.2{\pm}1.2$, $67.8{\pm}1.0$, $47.0{\pm}1.3$ and $47.1{\pm}1.1%$, respectively. The current-year-sprouted S. quelpaertenisis tended to have high nutritional values and digestibilities compared to those of the previous-year-sprouted. The dry matter yield, plant length, leaf width and density of S. quelpaertensis Nakai were clearly decreased by horse grazing. These results show that considering the feed value and growth characteristics, the natural S. quelpaertenisis Nakai can be used as a feed source for horses.

• Economic and Environmental Geology
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• v.44 no.2
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• pp.135-152
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• 2011

Nitrate concentrations in springs at the southern slope of Jeju Island were predicted using multiple linear regression (MLR) of spatial variables including hydrogeological parameters and land use characteristics. Springs showed wide range of nitrate concentrations from <0.02 to 86 mg/L with a mean of 20 mg/L. Spatial variables were generated for the circular buffer when the optimal buffer radius was assigned as 400 m. Selected regression models were tested using the p values and Durbin-Watson statistics. Explanatory variables were selected using the adjusted $R^2$, Cp (total squared error) and AIC (Akaike's Information Criterion), and significance. In addition, mutual linear relations between variables were also considered. Small portion of springs, usually <10% of total samples, were identified as outliers indicating limitations of MLR using circular buffers. Adjusted $R^2$ of the proposed models was improved from 0.75 to 0.87 when outliers were eliminated. In particular, the areal proportion of natural area had the greatest influence on the nitrate concentrations in springs. Among anthropogenic land uses, the influence of nitrate contamination is diminishing in the following order of orchard, residential area, and dry farmland. It is apparent quality of springs in the study area is likely to be controlled by land uses instead of hydrogeological parameters. Most of all, it is worth highlighting that the contamination susceptibility of springs is highly sensitive to nearby land uses, in particular, orchard.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.1
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• pp.1-7
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• 2010

This study was carried out to investigate total polyphenol contents, total flavonoid contents and antioxidative activities of the methanol extracts from dried Citrus sunki and C. unshiu peels. The dried C. sunki peels displayed higher total polyphenol and flavonoid contents for older dried peels. In contrast, the dried C. unshiu peels displayed higher total polyphenol contents for more recently dried and displayed high total flavonoid contents by order of 2007, 2008 and 2006. DPPH radical scavenging activities of dried C. sunki peels were high by order of 2007 (0.25 mg/mL exception), 2006 and 2008, but C. unshiu peels could not confirm clear regularity. In particular, the dried C. sunki (2008, exception) and C. unshiu peels displayed very high activities of more than 86% in 1.0 mg/mL. Alkyl radical scavenging activities of dried C. sunki peels were higher for older dried peels (2007, 1.0 mg/mL exception), and that of dried C. unshiu peels were higher for more recently dried in below 0.5 mg/mL but were higher for older peels in 1.0 mg/mL. Hydrogen peroxide scavenging activities of dried C. sunki peels were higher for older peels (2007, 2.5 mg/mL exception), on the other hand, dried C. unshiu were higher for more recently dried. In particular, dried C. unshiu peels displayed high activities of more than 85% in 2.5 mg/mL. Hydroxyl radical scavenging activities of dried C. sunki and C. unshiu peels displayed low activities compared to other reactive oxygen species as the range of $49.9\pm2.2\sim63.5\pm0.9$% in 1.0 mg/mL.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.15 no.1
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• pp.38-53
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• 2007

In a seminal judgment of November 2002 (Case C-476/98) relating to the compatibility with Community laws of the 'nationality clause' in the 1996 amending protocol to the 1955 U.S.-German Air Services Agreement, the European Court of Justice(ECJ) decided that the provision constituted a measure of an intrinsically discriminatory nature and was thus contrary to the principle of national treatment established under Art. 52 of the EC Treaty. The Court, rejecting bluntly the German government' submissions relying on public policy grounds(Art. 56, EC Treaty), seemed content to declare and rule that the protocol provision requiring a contracting state party to ensure substantial ownership and effective control by its nationals of its designated airlines had violated the requirement of national treatment reserved for other Community Members under the salient Treaty provision. The German counterclaims against the Commission, although tantalizing not only from the perusal of the judgment but from the perspective of international air law, were nonetheless invariably correct and to the point. For such a clause has been justified to defend the 'fundamental interests of society from a serious threat' that may result from granting operating licenses or necessary technical authorizations to an airline company of a third country. Indeed, the nationality clause has been inserted in most of the liberal bilaterals to allow the parties to enforce their own national laws and regulations governing aviation safety and security. Such a clause is not targeted as a device for discriminating against the nationals of any third State. It simply acts as the minimum legal safeguards against aviation risk empowering a party to take legal control of the designated airlines. Unfortunately, the German call for the review of such a foremost objective and rationale underlying the nationality clause landed on the deaf ears of the Court which appeared quite happy not to take stock of the potential implications and consequences in its absence and of the legality under international law of the 'national treatment' requirement of Community laws. Again, while US law limits foreign shareholders to 24.9% of its airlines, the European Community limits non-EC ownership to 49%, precluding any ownership and effective control by foreign nationals of EC airlines, let alone any foreign takeover and merger. Given this, it appears inconsistent and unreasonable for the EC to demand, $vis-{\grave{a}}-vis$ a non-EC third State, national treatment for all of its Member States. The ECJ's decision was also wrongly premised on the precedence of Community laws over international law, and in particular, international air law. It simply is another form of asserting and enforcing de facto extraterritorial application of Community laws to a non-EC third country. Again, the ruling runs counter to an established rule of international law that a treaty does not, as a matter of principle, create either obligations or rights for a third State. Aside from the legal problems, the 'national treatment' may not be economically justified either, in light of the free-rider problem and resulting externalities or inefficiency. On the strength of international law and economics, therefore, airlines of Community Members other than the designated German and U.S. air carriers are neither eligible for traffic rights, nor entitled to operate between or 'free-ride' on the U.S. and German points. All in all and in all fairness, the European Court's ruling was nothing short of an outright condemnation of established rules and principles of international law and international air law. Nor is the national treatment requirement justified by the economic logic of deregulation or liberalization of aviation markets. Nor has the requirement much to do with fair competition and increased efficiency.