• 지질공학
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• 제20권3호
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• pp.297-310
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• 2010

본 연구는 태안화력본부 회사장에 비회와 저회가 혼합되어 매립된 혼합회를 건설재료로 활용하기 위한 기초연구로서 대상 혼합회의 물리적 시험 및 역학적 시험을 실시하여 도로성토용 재료 및 구조물 뒤채움용 재료로 활용가능한지 판단하고자 공학적 특성을 검토하였다. 비중, 최대 최소밀도, 액 소성, 입도분석, XRD, 강열감량시험을 통해 물리 화학적 특성을 평가하였고 투수, 다짐, CBR, 삼축압축시험을 실시하여 역학적 특성을 평가하였다. 혼합회의 실험결과 비중은 2.18~2.20, 건조밀도는 $9.38{\sim}13.32\;kN/m^3$, 수정 CBR은 16.5~21%, 투수계수는 $1.32{\times}10^{-4}{\sim}1.89{\times}10^{-4}cm/sec$, 배수마찰각은 $36.43{\sim}41.39^{\circ}$로 나타났다. 물리 역학적 실험결과를 토대로 도로성토용 재료와 구조물 뒤채움용 재료로써의 품질기준과 비교해 본 결과 활용이 가능할 것으로 판단되었다. 그러나 비회의 함유율이 높은 혼합회는 일부 품질기준을 만족하지 못하므로 도로성토용 재료와 구조물 뒤채움용 재료로 활용하기 위해서는 저회와의 배합을 통한 품질개선이 필요할 것으로 판단되었다.

• 전기화학회지
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• 제10권2호
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• pp.116-125
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• 2007

This article is concerned with synthesis, characterisation and electrochemical application of the mixed conducting perovskite type oxide to electrode materials for solid oxide fuel cell. First, this review provides a comprehensive survey of the various synthetic methods such as solid state reaction, Pechini, glycine nitrate process and sol-gel methods for the preparation of perovskite type oxide powders. Subsequently, the electrical and microstructural properties of the mixed conducting oxides were discussed in detail. Finally, as electrochemical applications of the mixed conducting perovskite type oxides to electrode materials for solid oxide fuel cell, fundamentals of theoretical ac-impedance model for porous mixed conducting electrodes were introduced. Furthermore, the ac-impedance behaviour of porous and dense mixed conducting electrodes prepared by various synthetic methods was discussed.

• 조형예술학연구
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• 제6권
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• pp.203-225
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• 2004

We are sure that Abakanowicz positively assumes a position of members, which are represented the later modern fabric design. In sprite of his pervasive evaluation, we have doubt about his achievement because the preceding research is insufficient about argumentsuch as dependence on intuitive emotion study, conventional analysis of structure and insufficient inquiry of causa efficiens. We agree that basic structure of is dissipation. Though right and left symmetrical structure is similar, also that structure is different. We can't decide whether structure is unification structure, difference structure or mixture structure . We think that the time of confusing argument of his structure is changing period for disorganization trend. The result of this study confirm the research possibility about space organization with restructure analysis and verification for examining essence structure of sample text . The Thesis are concern that the different between paradigmatic appearances and syntagmatic, which exist . So, we can approach the meaning of system and find dominent point about constructional relationship on the works. The meaning of dominent point is understood about sexless trend or Androgyne, which are appeared Abakanowicz forth work period. The relationship structure which is mixed both issue show that inner issue of work is located the highest position. The paper presents confusing manufacture system, which are suggested man-woman sex and mixed meaning. The other result of this study are, 1. being known as Abakan algorism, Abakanowicz has new drafting idiom from his ancient belief. 2. we need to research the body texture of Abakanowicz with the trend of restructure of body study. 3. we need argue about gender study in relative with poster moderntheology related problem of sexlessness people and perfect sex-people.

• Coupled systems mechanics
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• 제7권6호
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• pp.649-668
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• 2018

In this paper, we present a numerical model for fluid-structure interaction between structure built of porous media and acoustic fluid, which provides both pore pressure inside porous media and hydrodynamic pressures and hydrodynamic forces exerted on the upstream face of the structure in an unified manner and simplifies fluid-structure interaction problems. The first original feature of the proposed model concerns the structure built of saturated porous medium whose response is obtained with coupled discrete beam lattice model, which is based on Voronoi cell representation with cohesive links as linear elastic Timoshenko beam finite elements. The motion of the pore fluid is governed by Darcy's law, and the coupling between the solid phase and the pore fluid is introduced in the model through Biot's porous media theory. The pore pressure field is discretized with CST (Constant Strain Triangle) finite elements, which coincide with Delaunay triangles. By exploiting Hammer quadrature rule for numerical integration on CST elements, and duality property between Voronoi diagram and Delaunay triangulation, the numerical implementation of the coupling results with an additional pore pressure degree of freedom placed at each node of a Timoshenko beam finite element. The second original point of the model concerns the motion of the outside fluid which is modeled with mixed displacement/pressure based formulation. The chosen finite element representations of the structure response and the outside fluid motion ensures for the structure and fluid finite elements to be connected directly at the common nodes at the fluid-structure interface, because they share both the displacement and the pressure degrees of freedom. Numerical simulations presented in this paper show an excellent agreement between the numerically obtained results and the analytical solutions.

• Bulletin of the Korean Chemical Society
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• 제29권11호
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• pp.2195-2201
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• 2008

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2800-2802
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• 2013

• 한국환경보건학회지
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• 제38권3호
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• pp.213-222
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• 2012

Objectives: This study was undertaken in order to evaluate by work space zoning and structure the concentrations of biological contaminants in the indoor air of domestic office buildings. Methods: Air samples were collected in the office spaces of 15 office buildings in Seoul from June 28 to July 28, 2011. Prior to the sampling, each office was classified into 'open-plan office', 'cellular office' and 'mixed office' according to the work space zoning. To evaluate the biological contamination of indoor air, total suspended bacteria (TSB), Gram positive bacteria (GPB), Staphylococcus aureus (S.A), Methicillin-resistant Staphylococcus aureus (MRSA), Gram negative bacteria (GNB) and fungi were investigated. During the sampling, temperature, relative humidity and carbon dioxide ($CO_2$) were measured. Results: The TSB concentrations ($GM{\pm}GSD$) were $452({\pm}1.3)cfu/m^3$ in open-plan offices, $366({\pm}1.3)cfu/m^3$ in cellular offices and $287({\pm}1.5)cfu/m^3$ in mixed offices, and there were significant differences between the three groups (p<0.05). The highest concentrations ($GM{\pm}GSD$) of fungi were found in the indoor air of cellular offices $128({\pm}1.0)cfu/m^3$, which was at least three times higher than the concentrations in mixed offices $43({\pm}1.0)cfu/m^3$ (p<0.05). Conclusions: Microbiological contamination in the indoor air of office buildings by work space structure was the highest with the open-plan office layout which includes no high walls or doors separating the occupants.

• 한국재료학회지
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• 제25권1호
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• pp.1-8
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• 2015

This study suggested comprehensive structural characterization methods for the commercial blue light emitting diodes(LEDs). By using the Z-contrast intensity profile of Cs-corrected high-angle annular dark field scanning transmission electron microscope(HAADF-STEM) images from a commercial lateral GaN-based blue light emitting diode, we obtained important structural information on the epilayer structure of the LED, which would have been difficult to obtain by conventional analysis. This method was simple but very powerful to obtain structural and chemical information on epi-structures in a nanometer-scale resolution. One of the examples was that we could determine whether the barrier in the multi-quantum well(MQW) was GaN or InGaN. Plan-view TEM observations were performed from the commercial blue LED to characterize the threading dislocations(TDs) and the related V-pit defects. Each TD observed in the region with the total LED epilayer structure including the MQW showed V-pit defects for almost of TDs independent of the TD types: edge-, screw-, mixed TDs. The total TD density from the region with the total LED epilayer structure including the MQW was about $3.6{\times}10^8cm^{-2}$ with a relative ratio of Edge- : Screw- :Mixed-TD portion as 80%: 7%: 13%. However, in the mesa-etched region without the MQW total TD density was about $2.5{\times}10^8cm^{-2}$ with a relative ratio of Edge- : Screw- :Mixed-TD portion of 86%: 5%: 9 %. The higher TD density in the total LED epilayer structure implied new generation of TDs mostly from the MQW region.

• 공업화학
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• 제22권5호
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• pp.545-550
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• 2011

바이오 분자의 고정 링커로 전기전도도가 높은 방향족 공액구조의 4-(2-(4-(acetylthio)phenyl)ethynyl)benzoic acid (APBA) 분자를 합성한 후, APBA 자기조립 단분자막을 제작하였다. 제작한 APBA 자기조립 단분자막의 구조를 분석하였고, 페로센으로 고정화시킨 APBA의 자기조립 단분자막의 전기화학적 특성을 조사하였다. 부탄티올 단분자막에 APBA를 삽입시켜 혼합 단분자막을 제조하여 XPS로 금 기판에 대한 혼합 단분자막의 수직 배향성을 조사하였다. 또한, APBA 혼합 시간에 따른 APBA와 부탄티올(BT) 혼합 단분자막에 페로센을 고정화하여 전기화학적 산화 환원 특성을 조사하였다. 혼합 단분자막의 전기화학적 활성은 혼합 시간의 증가에 따라 증가하였고, 부탄티올 단분자막 기판을 APBA 용액에 36 h 침지시켰을 때 가장 높은 페로센 분자의 산화 환원 전류값을 얻었다.

• 스마트미디어저널
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• 제11권9호
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• pp.81-93
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• 2022

비대면 만남이 일반화 되는 시대에 기존의 사진/영상을 기반으로 한 온라인 만남에서 충족되지 못하는 영역을 확장현실이 빠르게 발전해 나가며 채워가고 있다. 하지만, 가장 보편적으로 확장현실을 경험할 수 있는, 손을 주요 입력도구로 하는 HMD(Head Mount Display)형 혼합현실에서 적용되고 있는 기본 조작들은 표준화 된 체계가 없고 각각의 제조사들에 따라 다른 손동작에 별개로 대응되어 동작하고 있다. 이에 본 연구는 혼합현실에서 수행되는 조작들의 사용성과 효율성을 고려한 체계화된 손동작 매칭체계가 필요하다고 여겨 이를 규명하는 연구를 진행하였다. 먼저, MR환경에서 수행되는 기본적인 조작과 그 속성을 규명하였고, 동시에 손의 구조와 발생할 수 있는 손동작들의 속성들을 규명하였다. 규명한 속성들을 토대로 MR(Mixed Reality)환경에서의 기본조작과 손의 구조/맥락에 따른 미묘한 작동속성을 직관적이고 효율적으로 매칭할 수 있는 체계를 제시하고자 한다.