• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.1093-1098
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• 2007

In designing the high-speed railroad track, it is important to utilize appropriate track components to maintain uniform stiffness and ensure track alignment within the tolerance set for that system. In this regard, continuous welded rails (CWRs) were introduced to the Korean railways. Yet the installation of CWRs can result in an adverse impact due to the track/structure interaction on bridge sections yielding variations in the stiffness at the expansion joints. It may also impose additional axial force, generate excessive stress or deflection on track, and loosen the ballast at the ends as a bridge deck contracts or expands owing to a thermally-induced dynamic response. The risk is even greater in a long bridge deck, resulting in track longitudinal irregularities, deteriorating passenger's comfort, and increasing maintenance efforts. This study evaluates the performance of ZLR and their impact on track longitudinal irregularities through the track measuring results on a test section installed the ZLR in order to minimize the thermally-induced responses and the maintenance efforts for the high speed railway bridges.

• Earthquakes and Structures
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• 제1권3호
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• pp.253-267
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• 2010

A novel simple approach is presented for the seismic analysis of continuous buried pipelines subject to fault ruptures. The method is based on the minimization of the total dissipated energy during faulting, taking into account the basic factors that affect the problem, namely: a) the pipe yielding under axial and bending load, through the formation of plastic hinges and axial slip; b) the longitudinal friction across the pipe-soil interface; c) the lateral resistance of soil. The advantages and drawbacks of the proposed method are highlighted through a comparison with previous approaches, as well as with finite element calculations accounting for the 3D kinematics of the pipe-soil-fault systems under large deformations. Parametric analyses are also provided to assess the relative influence of the various parameters affecting the problem.

• Earthquakes and Structures
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• 제9권3호
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• pp.503-539
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• 2015

A new constitutive model for the representation of the seismic behaviour of steel bars including hardening phenomena is presented. The model takes into account relative slip between bars and concrete, necessary for the estimation of the structural behaviour of r.c. elements and of the level of strain induced by earthquakes on bars. The present work provides the analytical formulation of the post-yielding behaviour of reinforcements, resulting in a continuous axial stress-slip relationship to be implemented in engineering software. The efficacy of the model is proved through the application to a cantilever column, for whose bars the constitutive law is derived.

• Nuclear Engineering and Technology
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• 제49권6호
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• pp.1326-1338
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• 2017

The continuous energy Monte Carlo neutron transport code, MC21, was coupled to the CTF subchannel thermal-hydraulics code using a combination of Consortium for Advanced Simulation of Light Water Reactors (CASL) tools and in-house Python scripts. An MC21/CTF solution for VERA Core Physics Benchmark Progression Problem 6 demonstrated good agreement with MC21/COBRA-IE and VERA solutions. The MC21/CTF solution for VERA Core Physics Benchmark Progression Problem 7, Watts Bar Unit 1 at beginning of cycle hot full power equilibrium xenon conditions, is the first published coupled Monte Carlo neutronics/subchannel T-H solution for this problem. MC21/CTF predicted a critical boron concentration of 854.5 ppm, yielding a critical eigenvalue of $0.99994{\pm}6.8E-6$ (95% confidence interval). Excellent agreement with a VERA solution of Problem 7 was also demonstrated for integral and local power and temperature parameters.

• 한국육종학회지
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• 제41권4호
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• pp.539-542
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• 2009

A new gerbera variety "Pink Swan" was released by the National Horticultural Research Institute (NHRI) in 2007. A cross was made between "Royal" with orange and single and 'Himalaya' with white and semi-double in 2004. After investigation of the characteristics for 4 years (from 2004 to 2007), it was selected specially for the use of cut-flower. "Pink Swan" is a vigorous medium-sized cultivar with pink (RHS R48D), yellow green center and semi-double. The average flower diameter is 10.6 cm. And inner ray floret and disc diameter is 5.99cm and 1.83cm, respectively. It produces a large yield with continuous supply of flowers and has adequate peduncle height. We believe that "Pink Swan" has a great potential for expanding cultivated area of domestic gerbera cultivar and increasing farmers-income.

• 한국육종학회지
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• 제40권4호
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• pp.499-502
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• 2008

A new gerbera variety 'Yellow Wing' was released by the National Horticultural Research Institute (NHRI) in 2007. A cross was made between 'Gold Finger' with yellow and single and 'Yellow Springs' with yellow and spider in 2004. After investigation of the characteristics for 4 years (from 2004 to 2007), it was selected specially for the use of cut-flower. 'Yellow Wing' is a vigorous cultivar with yellow (RHS YO14B), green center and spider type. The flower diameter is 10.6cm. And inner ray floret and disc diameter is 2.83cm and 2.03cm, respectively. It produces a large yield with continuous supply of flowers and has adequate peduncle height and brilliant color. We believe that 'Yellow Wing' has a great potential for expanding cultivated area of domestic gerbera cultivar and increasing farmers-income.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1986년도 추계학술대회
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• pp.509.2-509
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• 1986

Owing to the growing interest in the production of fuels and chemicals from biomass the well-know butanol-acetone fermentation as carried out by Clostridium acetobutylicum has been intensely studied again in recent years. Several solvent-yielding fermentation processes were established which are operated by using batch cultures or continuous cultures. 1 could be shown that under conditions of phosphate limitation an asporogenous mutant of C. acetobutylicum establishes itself in a chemostat which produces the solvents continuously. Attempts have been made to change the butanol/acetone ratio in favor of butanol production. A corresponding shift of the product spectrum can be achieved by carbon monoxide addition to the head space of the fermentation (B.H. Kim et al., App. Envioron. Microbiol. 48, 764-770 1984) or by iron limitation. Progress has been made in understanding the mechanism underlying the shift from acid to solvent prodcction. Experimental results are in agreement with the view that intracellular accumulation of acetic and butyric acid results in a shortage of phosphate and coenzyme A. This shortage may serve then as signal for the synthesis of the enzymes involved in the formation of acetone and butanol.

• 대한기계학회논문집
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• 제11권6호
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• pp.913-922
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• 1987

본 연구에서는 Sn-15% Pb 재료에 대하여 실험에 의한 쌍 로울식 연속 주조의 주조특성을 구하고 로울러 열팽창과 열응력에 대한 유한요소해석을 통하여 제품 두께 와 로울러 변형과의 관계를 밝히고자 한다.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2002년도 창립 10주년 기념 국제학술심포지움
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• pp.46-53
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• 2002

The self-sufficiency of rice production was attained in 1975 through development of Tongil-type high-yielding rices and rapid dissemination to farmers and innovation of cultivation technologies, so-called "green revolution" in Korea. It can be continued during the last twenty seven years except some years with meterological disasters. The national average of milled rice yield per ha was only 3.1 ton at the first half of 1960′s, but it drastically increased to 5.0 ton at the 2nd half of 1990′s. Also, the rice quality was highly improved through the continuous varietal improvement of high-yielding japonica rice cultivars. The amounts of rice stock will go beyond about 1.9 million tons in 2002 due to the recent continuos bumper rice crop and relatively rapid reducing in rice consumption. There are so many rice brands over 1,200 in Korea, but most of rice commodities are not enough controlled in terms of marketing quality and palatability of cooked rice. Although the most rice brands are not properly controlled in quality management, its average level of grain quality is largely improved through the continuously increased diffusion of newly-developed high-quality rice cultivars since 1991. The rapid construction of rice processing complex(RPC) since 1992 also accelerates the production and distribution of brand rices. Especially, about half of distribution amounts are covered by brand rice commodities of the agricultural cooperative associations. The rice is mainly consumed by the type of cooked rice. The amounts of rice consumption for food processing is only below 4% of total rice consumption. The processed rice foods is mainly consumed as various processed cooked rices, rice cakes, and rice wines.

• 한국산학기술학회논문지
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• 제17권10호
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• pp.666-677
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• 2016

본 연구는 국내 카드사의 전략적 마케팅 제휴의 성과에 영향을 미치는 요인을 소비자 수준과 기업 수준으로 구분되는 다수준데이터를 통해 분석해 보았다. 이를 위해 국내에 출시된 30개의 제휴카드를 표본으로 선정하여 두 개의 기업요인을 측정하였고, 표본으로 선정된 제휴카드의 회원 610명을 대상으로 세 개의 소비자 요인과 지속사용의도를 측정하였다. 다수준데이터 구조에 적합한 위계적 선형모형(HLM)을 통해 분석한 결과, 제휴카드 혜택, 혜택 정보제공, 제휴사브랜드 등 소비자 데이터로 측정한 요인 모두 지속사용의도에 긍정적 영향을 미친다는 것을 확인하였다. 기업변수 중에는 제휴목표의 적합성 변수가 영향력이 확인된 반면, 제휴사의 마케팅역량은 지속사용의도에 영향을 미치지 않는 것으로 나타났으며, 기업수준의 변수들은 소비자 수준 변수들이 갖는 영향력에 대해 긍정적인 조절효과를 갖지 않는 것으로 확인되었다. 본 연구는 국내 신용카드 산업에 대해 소비자 수준과 기업 수준의 요인들이 갖는 종합적인 영향력을 분석한 거의 최초의 연구로서 관련 연구에 새로운 시각을 제공함은 물론 치열한 경쟁 환경하의 카드사들에게 의미 있는 전략적 시사점을 제시했다는 점에서 그 의의를 찾을 수 있다.