• 제목/요약/키워드: Structure function

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이중주격구문의 의미구조 (Semantic Structure of Double Nominative Constructions)

  • 김경환
    • 한국콘텐츠학회논문지
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    • 제20권5호
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    • pp.338-343
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    • 2020
  • 언어의 통사, 의미, 형태 등 여러 다른 영역들을 동시에 그리고 독립적으로 생성되는 모듈로 보는 자율어휘문법을 기반으로 이중주격에 대한 의미론적 분석을 제시하는 것이 본 논문의 목적이다. 과거의 통사중심주의적 이론에서는 이중주격에 대한 분석방식으로 소유자인상, 예외적 격부여, 병합 등이 제시되었다. 통사중심주의적 이론과 달리 본 논문에서는 내적소유와 외적소유에 대한 기능-논항구조를 밝혀 이중주격에 대한 의미론적 분석을 제시한다. 이중주격에 사용되는 소유대상은 관계명사로 기능-논항구조에서 소유자를 논항으로 취하는 것으로 본다. 소유자에 해당되는 이 논항이 바로 관계명사와 결합하면 내적소유구문이 생성된다. 반면에 소유자가 공백상태인 경우 소유자와 공지시관계인 논항이 최종적으로 술어와 결합하여 그 결과 소유자가 주격으로 표현되는 외적소유구문이 생성된다. 외적소유의 기능-논항구조는 해당 문장이 내적소유와 달리 주격으로 표현된 소유자에 대해 서술하고 있음을 구조적으로 보여준다.

각분해 광전자 분광법을 이용한 Pd(111)의 전자구조 연구 (Electronic Structure of Pd(111) using Angle-Resolved Phothemission Spectroscopy)

  • 황도원;강정수;홍재화;정재인;문종호;김건호;이정주;이영백;홍순철;민병일
    • 한국진공학회지
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    • 제5권1호
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    • pp.14-24
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    • 1996
  • We have investigated atomic and electronic structures of a clean Pd(111) surface using low energy electron diffraction (LEED) and angle-resolved photoemission spectroscopy (ARPES). A typical clean LEED pattern with a 3-fold symmetry has been observed, corresponding to that for an fcc (111) surface. ARPES measurements have been performed along the $\Gamma-M,\Gamma-K,\Gamma-M$TEX> symmetry lines, from which the experimental band structure of Pd(111) has been determined. The experimental band structure and work function of Pd(111) surface are found to agree well with the calculated band structure of bulk Pd and the calculated work function of Pd(111), respectively. However, the peak positions in the experimental band structure are located closer to the Fermi level than in the theoretical band structure by 0.1~0.8 eV, depending on the $\kappa$-points in the Brillouin zone. In additin, the experimental band widths are narrower than the theoretical band widths by about 0.5eV. The effects of the localized surface Pd 4d states and the Coulomb interaction between Pd 4d bulk electrons have been discussed as possible origins of such discrepancies between experiment and theory.

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해양환경의 변동성을 고려한 해상풍력터빈 지지구조물의 기대수명 평가 (Expected Life Evaluation of Offshore Wind Turbine Support Structure under Variable Ocean Environment)

  • 이기남;김동현;김영진
    • 한국해양공학회지
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    • 제33권5호
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    • pp.435-446
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    • 2019
  • Because offshore structures are affected by various environmental loads, the risk of damage is high. As a result of ever-changing ocean environmental loads, damage to offshore structures is expected to differ from year to year. However, in previous studies, it was assumed that a relatively short period of load acts repeatedly during the design life of a structure. In this study, the residual life of an offshore wind turbine support structure was evaluated in consideration of the timing uncertainty of the ocean environmental load. Sampling points for the wind velocity, wave height, and wave period were generated using a central composites design, and a transfer function was constructed from the numerical analysis results. A simulation was performed using the joint probability model of ocean environmental loads. The stress time history was calculated by entering the load samples generated by the simulation into the transfer function. The damage to the structure was calculated using the rain-flow counting method, Goodman equation, Miner's rule, and S-N curve. The results confirmed that the wind speed generated at a specific time could not represent the wind speed that could occur during the design life of the structure.

직교배열실험 방법 기반 해양플랜트 플로트오버 설치 공법용 수동형 DSF의 구조설계 민감도와 메타모델링 평가 (Evaluation on Structure Design Sensitivity and Meta-modeling of Passive Type DSF for Offshore Plant Float-over Installation Based on Orthogonal Array Experimental Method)

  • 이동준;송창용
    • 한국기계가공학회지
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    • 제20권5호
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    • pp.85-95
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    • 2021
  • Structure design sensitivity was evaluated using the orthogonal array experimental method for passive-type deck support frame (DSF) developed for float-over installation of the offshore plant. Moreover, approximation characteristics were also reviewed based on various meta-models. The minimum weight design of the DSF is significantly important for securing both maneuvering performance and buoyancy of a ship equipped with the DSF and guaranteeing structural design safety. The performance strength of the passive type DSF was evaluated through structure analysis based on the finite element method. The thickness of main structure members was applied to design factors, and output responses were considered structure weight and strength performances. Quantitative effects on the output responses for each design factor were evaluated using the orthogonal array experimental method and analysis of variance. The optimum design case was also identified from the orthogonal array experiment results. Various meta-models, such as Chebyshev orthogonal polynomial, Kriging, response surface method, and radial basis function-based neural network, were generated from the orthogonal array experiment results. The results of the orthogonal array experiment were validated using the meta-modeling results. It was found that the radial basis function-based neural network among the meta-models could approximate the design space of the passive type DSF with the highest accuracy.

Biotinoyl Domain of Human Acetyl-CoA Carboxylase;Structural Insights into the Carboxyl Transfer Mechanism

  • Lee, Chung-Kyung;Cheong, Hae-Kap;Ryu, Kyoung-Seok;Lee, Jae-Il;Jeon, Young-Ho;Cheong, Chae-Joon
    • 한국자기공명학회논문지
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    • 제12권1호
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    • pp.1-13
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    • 2008
  • Acetyl-CoA carboxylase (ACC) catalyzes the first step in fatty acid biosynthesis: the synthesis of malonyl-CoA from acetyl-CoA. As essential regulators of fatty acid biosynthesis and metabolism, ACCs are regarded as therapeutic targets for the treatment of metabolic diseases such as obesity, In ACC, the biotinoyl domain performs a critical function by transferring an activated carboxyl group from the biotin carboxylase domain to the carboxyl transferase domain, followed by carboxyl transfer to malonyl-CoA. Despite the intensive research on this enzyme, only the bacterial and yeast ACC structures are currently available, To explore the mechanism of ACC holoenzyme function, we determined the structure of the biotinoyl domain of human ACC2 and analyze its characteristics using NMR spectroscopy. The 3D structure of the hACC2 biotinoyl domain has a similar folding topology to the previously determined domains from E. coli and P. Shermanii, however, the 'thumb' structure is absent in the hACC2 biotinoyl domain. Observations of the NMR signals upon the biotinylation indicate that the biotin group of hACC2 does not affect the structure of the biotinoyl domain, while the biotin group for E. coli ACC interacts directly with the thumb residues that are not present in the hACC2 structure. These results imply that, in the E. coli ACC reaction, the biotin moiety carrying the carboxyl group from BC to CT can pause at the thumb of the BCCP domain. The human biotinoyl domain, however, lacks the thumb structure and does not have additional non-covalent interactions with the biotin moiety; thus, the flexible motion of the biotinylated lysine residue must underlie the "swinging arm" motion. This study provides insight into the mechanism of ACC holoenzyme function and supports the "swinging arm" model in human ACCs.

Family of floral homeotic genes (MADS-box genes) expressed in early flower Panax genseng

  • Yoon, Sunha;Yoon, Euisoo
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2002년도 심포지엄
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    • pp.98-98
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    • 2002
  • In higher dicotyledonous plants, the floral organs are arranged in four different whorls, containing sepals, stamens and carpels. petals, stamens and carpels. The specification of floral organ identity is explained by the ABC model (Weigel and Meyerowitz 1994). expression of an A-function gene specifies sepal formation in whorl 1. the combination of A-and B-function genes specifies the formation of petals in whorl 2, B-and C-function genes spesify stamen formation in whorl 3, and expression of the C-function alone determines the formation of carpels in whorl 1. A-, B-, C-function genes have been isolated from many plant species and most of them belong to the family of MADS-box genes encoding transcription factor. In contrast to the flower of higher dicots, the perianths of genseng plants have three whorls of almost identical petaloid organs. van Tunen et al. (1993) proposed a modified ABC model, exemplified with tulip. In this model, B-function genes are expressed in whorl 1 as well as whorl 2 and 3, theefore the organs of whorl 1 and whorl 2 have the same petaloid structure. They proposed this model with the molphological data of wild type and mutant flowers of tulip, however, there are no molecular data. To date, B-function genes were isolated several grass plants, rice, wheat and maize. However, grass plants have highly derived flowers, without well-developed perianths. To find out how the ABC model has to be modified for the Genseng plants, we have cloned and characterized orthologs of A-, B-, C-function genes from genseng.

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차체구조의 구조기인 내구 설계 (Structure Borne Durability Design of a Vehicle Body Structure)

  • 김효식;임홍재
    • 한국자동차공학회논문집
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    • 제12권3호
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    • pp.109-121
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    • 2004
  • This paper presents an optimal design method for structure-borne durability of a vehicle body structure. Structure-borne durability design requires a new design that can increase fatigue lives of critical areas in a structure and must prohibit transition phenomenon of critical areas that results from modification of the structure at the same time. Therefore, the optimization problem fur structure-borne durability design are consists of an objective function and design constraints of 2 types; type 1-constraint that increases fatigue lives of the critical areas to the required design limits and type 2-constraint that prohibits transition phenomenon of critical areas. The durability design problem is generally dynamic because a designer must consider the dynamic behavior such as fatigue analyses according to the structure modification during the optimal design process. This design scheme, however, requires such high computational cost that the design method cannot be applicable. For the purpose of efficiency of the durability design, we presents a method which carry out the equivalent static design problem instead of the dynamic one. In the proposed method, dynamic design constraints for fatigue life, are replaced to the equivalent static design constraints for stress/strain coefficients. The equivalent static design constraints are computed from static or eigen-value analyses. We carry out an optimal design for structure-borne durability of the newly developed bus and verify the effectiveness of the proposed method by examination of the result.

Theoretical prediction on thickness distribution of cement paste among neighboring aggregates in concrete

  • Chen, Huisu;Sluys, Lambertus Johannes;Stroeven, Piet;Sun, Wei
    • Computers and Concrete
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    • 제8권2호
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    • pp.163-176
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    • 2011
  • By virtue of chord-length density function from the field of statistical physics, this paper introduced a quantitative approach to estimate the distribution of cement paste thickness between aggregates in concrete. Dynamics mixing method based on molecular dynamics was employed to generate one model structure, then image analysis algorithm was used to obtain the distribution of thickness of cement paste in model structure for the purpose of verification. By comparison of probability density curves and cumulative probability curves of the cement paste thickness among neighboring aggregates, it is found that the theoretical results are consistent with the simulation. Furthermore, for the model mortar and concrete mixtures with practical volume fraction of Fuller-type aggregate, this analytical formula was employed to predict the influence of aggregate volume fraction and aggregate fineness. And evolution of its mean values were also investigated with the variation of volume fraction of aggregate as well as the fineness of aggregates in model mortars and concretes.

Material distribution optimization of 2D heterogeneous cylinder under thermo-mechanical loading

  • Asgari, Masoud
    • Structural Engineering and Mechanics
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    • 제53권4호
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    • pp.703-723
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    • 2015
  • In this paper optimization of volume fraction distribution in a thick hollow cylinder with finite length made of two-dimensional functionally graded material (2D-FGM) and subjected to steady state thermal and mechanical loadings is considered. The finite element method with graded material properties within each element (graded finite elements) is used to model the structure. Volume fractions of constituent materials on a finite number of design points are taken as design variables and the volume fractions at any arbitrary point in the cylinder are obtained via cubic spline interpolation functions. The objective function selected as having the normalized effective stress equal to one at all points that leads to a uniform stress distribution in the structure. Genetic Algorithm jointed with interior penalty-function method for implementing constraints is effectively employed to find the global solution of the optimization problem. Obtained results indicates that by using the uniform distribution of normalized effective stress as objective function, considerably more efficient usage of materials can be achieved compared with the power law volume fraction distribution. Also considering uniform distribution of safety factor as design criteria instead of minimizing peak effective stress affects remarkably the optimum volume fractions.

Ti-(44-54)at.%Al 열처리 주조합금의 미세조직과 인장특성에 관한 연구 (A Study on the Microstructures and Tensile Properties of Heat-Treated Cast Ti-(44-54)at.%Al Alloys)

  • 정재영
    • 한국주조공학회지
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    • 제37권6호
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    • pp.199-206
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    • 2017
  • In this study, the variations of microstructures and tensile properties of Ti-(44-54)at.%Al binary alloys were investigated. The heat-treated microstructure depended greatly on their solidification structure and annealing temperature. We measured the variations of volume fractions of primary and secondary lamellar structure as a function of the heat treatment temperature in a Ti-47at.%Al alloy. The variation of ductility as a function of Al content was in good agreement with the change of fracture mode in the tensile fracture surface. It can be inferred that the variations of yield stress and hardness of ${\gamma}$ phase in a single ${\gamma}$-phase field region are enhanced by anti-site defects created by deviations from the stoichiometric composition. In a Ti-47at.%Al alloy within the (${\alpha}_2+{\gamma}$) two-phase field, the yield stress tended to be the maximum at a near equal volume fraction of lamellar and ${\gamma}$ grains. The ductility depended sensitively on the overall grain size and Al content. The calculation of fracture strain using Chan's model indicated that the change of ductility as a function of annealing temperature was primarily determined by the variations in the overall grain size and lamellar volume fraction.