• 한국지반신소재학회논문집
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• 제15권4호
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• pp.25-32
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• 2016

지반공학에서 평면변형율을 가정하는 2차원 사면안정해석은 일반적으로 널리 사용되고 있다. 이 가정은 사면활동이 넓은 영역에 걸쳐서 발생되는 가정이므로 3차원 효과가 무시된다. 대다수 연구에서 2차원해석의 최소안전율값은 3차원해석에 비하여 작게 평가되는 보수적인 결과를 나타낸다. 최근에는 컴퓨터의 소프트웨어와 하드웨어를 포함한 해석방법의 발달로 3차원해석에 대한 요구가 커지고 있다. 본 논문에서는 원호모드, 병진모드사면을 이용하여 유한요소에 의한 2, 3차원해석 및 2차원 한계평형해석을 통하여 수치해석을 실시하였다. 해석결과 매개변수(요소망크기, 체적팽창각(dilatency angle), 경계조건, 응력이력, 모델차원)에 따른 사면안정해석에 미치는 영향을 분석하였다. 해석결과 2차원 해석보다 3차원 해석에 의한 사면의 안전율 값은 항상 크게 평가되며, W 뱡향 경계조건이 롤러지지인 경우, 사면폭에 의한 결과 차이는 없는 것으로 조사되었다.

• 한국게임학회 논문지
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• 제5권2호
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• pp.3-9
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• 2005

인터렉티브 리얼 타임 3D(Interactive real-time 3D)는 유저가 가상의 3차원 세계를 탐색하고 또한 몰입하는 폼의 컨텐츠를 경험할 수 있게 해준다. 다른 매체와는 다르게, 인터렉티브 리얼 타임 3D의 사용자(user)는, 디지털 3D의 구조에서의 작용과 반작용이 즉시 일어나는 "실시간"에서 진행되는 프로세스에서 능동적인 역할을 수행한다.

• Earthquakes and Structures
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• 제16권2호
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• pp.221-234
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• 2019

Today, many important concrete face rockfill dams (CFRDs) have been built on the world, and some of these important structures are located on the strong seismic regions. In this reason, examination and monitoring of these water construction's seismic behaviour is very important for the safety and future of these dams. In this study, the nonlinear seismic behaviour of Ilısu CFR dam which was built in Turkey in 2017, is investigated for various reservoir water heights taking into account 1995 Kobe near-fault and far-fault ground motions. Three dimensional (3D) finite difference model of the dam is created using the FLAC3D software that is based on the finite difference method. The most suitable mesh range for the 3D model is chosen to achieve the realistic numerical results. Mohr-Coulomb nonlinear material model is used for the rockfill materials and foundation in the seismic analyses. Moreover, Drucker-Prager nonlinear material model is considered for the concrete slab to represent the nonlinearity of the concrete. The dam body, foundation and concrete slab constantly interact during the lifetime of the CFRDs. Therefore, the special interface elements are defined between the dam body-concrete slab and dam body-foundation due to represent the interaction condition in the 3D model. Free field boundary condition that was used rarely for the nonlinear seismic analyses, is considered for the lateral boundaries of the model. In addition, quiet artificial boundary condition that is special boundary condition for the rigid foundation in the earthquake analyses, is used for the bottom of the foundation. The hysteric damping coefficients are separately calculated for all of the materials. These special damping values is defined to the FLAC3D software using the special fish functions to capture the effects of the variation of the modulus and damping ratio with the dynamic shear-strain magnitude. Total 4 different reservoir water heights are taken into account in the seismic analyses. These water heights are empty reservoir, 50 m, 100 m and 130 m (full reservoir), respectively. In the nonlinear seismic analyses, near-fault and far-fault ground motions of 1995 Kobe earthquake are used. According to the numerical analyses, horizontal displacements, vertical displacements and principal stresses for 4 various reservoir water heights are evaluated in detail. Moreover, these results are compared for the near-fault and far-faults earthquakes. The nonlinear seismic analysis results indicate that as the reservoir height increases, the nonlinear seismic behaviour of the dam clearly changes. Each water height has different seismic effects on the earthquake behaviour of Ilısu CFR dam. In addition, it is obviously seen that near-fault earthquakes and far field earthquakes create different nonlinear seismic damages on the nonlinear earthquake behaviour of the dam.

• Journal of Microbiology and Biotechnology
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• 제12권3호
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• pp.371-376
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• 2002

A biosurfactant-producing bacterial strain was selected from diesel-contaminated soil by measuring the oil-film collapsing activity and identified as Pseudomonas aeruginosa D2D2. When glucose and olive oil were used as carbon sources, 11.46 g/1 of biosurfactant was obtained. Based on TLC analysis, the biosurfactant produced from P. aeruginosa D2D2 was identified as a glycolipid, consisting of two types of biosurfactants (Type I and Type II). The purified glycolipid reduced the surface tension of the culture from 72 dyne/cm to 27 dyne/cm. The hydrophilic and hydrophobic moiety of the biosurfactant were rhamnose and ${\beta}$-hydroxydecanoic acid, as determined by FAB-MS and NMR analyses, respectively.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2007년도 정기 학술대회 논문집
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• pp.301-306
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• 2007

Design of civil infrastructures is generally based on 2-D drawings and analyses. Design provisions also specify the limit states using member based equations. Most construction projects are done through collaboration of engineers who have different specialized knowledge. Information technologies can dramatically enhance the performance of the collaboration. For the information transfer, we need a mediator between engineers. Object based 3-D models are useful for the communication and for the owners who have to maintain whole the information of infrastructures. In this paper, basic guidelines for the 3-D design according to design phases. Adequate interoperability of 3-D objects from any CAD system is essential for the collaboration. Owners, contractors and design consultants were considered as users of 3-D objects. Cost and performance of each design phases was investigated through the existing data.

• Animal cells and systems
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• 제2권4호
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• pp.495-500
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• 1998

D-type G1 cyclins are known to be crucial for the progression of mitotic cell cycle in mammals. Although many studies have been performed to elucidate the roles of D-type cyclins, it is largely unknown whether D-type cyclins are directly involved in the regulation of meiotic germ cell development. In the present study, we examined the expression patterns of D-type cyclins (cyclin D1 and D3) during male germ cell development by northern blot and in situ Hybridization analyses. In the adult testes, we detected a 4.2 kb cyclin D1 mRNA and two different sizes (2.3 kb and 1.8 kb) of cyclinD3 mRNAs. The short form of the cyclin D3 transcript was testis-specific. Along with the testicular development, expression of cyclin D3 mRNA was increased whereas cyclin D1 mRNA was gradually decreased. in situ hybridization study also revealed that the expression of cyclin D3 was restricted to the postmeiotic germ cells. Furthermore, the 2.3 kb transcript was highly expressed in the round spermatids and decreased in the elongated spermatids/residual bodies, while the 1.8 kb transcript was expressed in elongated spermatids/residual bodies more abundantly. Sucrose-gradient separation of polysomal RNA fractions demonstrated that some portions of the 2.3 kb transcript are translationally active, while the 1.8 kb transcript is likely to be inactive. Taken together, the present data suggest a functional importance of cyclin D3 expression in the differentiated postmeiotic male germ cells.

• Natural Product Sciences
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• 제15권1호
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• pp.12-16
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• 2009

Phytochemical investigation of Metasequoia glyptostroboids leaves resulted in the isolation of ten compounds. The structures were determined to be isoquercitrin (1), quercitrin (2), myricitrin (3), amentoflavone (4), sciadopitysin (5), isoginkgetin (6), 2,3-dihydrosciadopitysin (7), 2,3-dihydroisoginkgetin (8), $3{\beta}$-acetoxy-8(17),13E-labdadien-15-oic acid (9) and $\beta$-sitosterol (10) by spectroscopic analyses. Isoquercitrin (1) was isolated from this plant for the first time.

• 한국해양공학회지
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• 제24권5호
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• pp.88-93
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• 2010

Many pipes that are arranged longitudinally in ships have loops at intervals to prevent the failure of the pipes as they absorb large portions of the axial load caused by the bending of the hull girder and/or thermal loads when the pipes are carrying very hot fluids. Since the loops are curved at corners, an efficient method for conducting the structural analyses of these curved portions is required. In this paper, a pipe loop was analyzed by an analytical method and by the finite-element method in four different ways, i.e., based on straight-beam elements, curved-beam elements, 2-D shell elements, and 3-D solid elements. The results of the five analyses were compared to check the validity of the current curved-beam theory. The paper includes some suggestions on how to analyze the pipe loops efficiently.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.249.2-250
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• 2003

3D-QSAR analyses by CoMFA and CoMSIA were conducted on a series of thiazole and triazole analogues with respect to their antifungal activities against Microsporum gypseum. A total of twenty analogues were used for the derivation of the 3D-QSAR models (training set). Thesuperposition of the compounds was performed by applying the FlexS with shape-based screening method. (omitted)

• Bulletin of the Korean Chemical Society
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• 제32권3호
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• pp.1027-1029
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• 2011

Two new phenolic glycosides were isolated from the rhizomes of Curculigo orchioides Gaertn.. Based on comprehensive spectroscopic analyses including IR, MS, 1D- and 2D NMR (COSY, HSQC, and HMBC), their structures were elucidated as 3-hydroxyl-5-methyphenol-1-O-[${\beta}$-D-glucopyranosyl-($1{\rightarrow}3$)-${\beta}$-D-glucopyranoside (1) and 1',3'-dimethoxyl-4-hydroxyalangifolioside (2).