The new rotary friction damper was developed using several two-nodal rotary frictional components with different clamping forces. Because of these components, the rotary friction damper can be activated by building movements due to lateral forces such as a wind and earthquake. In this paper, various dependency tests such as displacement amplitude, forcing frequency and long term cyclic loading were carried out to evaluate on the structural performance and the multi-slip mechanism of the new damper. Test results show that the multi-slip mechanism is verified and friction coefficients are dependent on displacement amplitute and forcing frequency except long term cyclic loading.

To overcome the weakness of spread foundation in large space structure, the research of precast pile for replace spread foundation have been conducted. The new type of joint between PHC pile and steel column is named HAT Joint(Hollow hAlf-sphere cast-sTeel Joint). It connected PHC Pile by bolt that verification of bolt connection should be accomplished. In this paper, pull-out test and flexural performance for HAT Joint to verifying the bolt connection is explained. As a result, the pull-out and flexural capacities of bolt were checked to use in real structure. Furthermore, the equation of pull-out strength was proposed.

연구성과를 향상시키는 데 중요한 요인은 연구자의 역량, 연구비 등의 자원 투 입 등이 지적되었다. 하지만 최근에는 공동연구가 활성화되면서 연구자 사이의 구조적 특성 을 통해 지속적 상호관계를 형성하여 과학적 지식을 생산하고 있기 때문이다. 하지만 이러한 연구비 지원이 지원 자체에 그치는 것이 아니라 연구비 지원으로 인해 다수의 기관이 협력하 여 연구를 수행할 수 있는 발판이 된다는 점에서 연구성과에 영향을 미치는 것으로 볼 수 있 다. 즉 연구비 지원이 공동연구의 연결구조에 차이를 발생시켜 연구성과에 영향을 미치기 때 문으로 추정할 수 있다. SCIE DB에서 2009년부터 2013년까지 5년간 문화기술(CT) 분야의 공동연구 논문을 대상으로 연구비 지원 여부에 따른 네트워크 구조와 연구성과의 관계를 분 석한 결과 다수의 연구기관이 연결되어 있을수록 논문 편수가 증가하고 사이 중심성이 증가할수록 논문 편수는 감소하는 것으로 분석되었다. 또한 연구비 지원 여부가 네트워크 구조, 연구성과에 영향을 미치는 것으로 분석되었다.

The construction of vinyl greenhouses are increasing because of economic feasibility, construction period, and construction regulations. However, the vinyl greenhouses are apt to collapse by snow load since they have a small member as a temporary structure. The 3 types of buckling such as global, member and nodal buckling could be occurred to arched structures according to characteristics of cross section. To examine the member buckling, the precision of analysis need to be enhanced. In that case, we can examine the characteristics of the those buckling. The purposes of this study are to verify buckling characteristics of structures using the method of high precision analysis with a center node of member. The results of high precision analysis bring member buckling, and in the analysis method having the center node of member, the value of strength is getting lower than a previous study.

Various hybrid dampers have been developed in Korea to control the vibration due to a wind and earthquake. In order to minimize the installment space, cost and construction process, the new hybrid friction damper is developed. This hybrid damper is composed of several rotary friction components having two frictional joint. Because of these components, the building vibration due to wind and earthquake can be mitigated by hybrid friction damper. In this paper, various dependency tests were carried out to evaluate on the structural performance of two joint rotational friction component of the hybrid damper. Test results show that two joint rotational components do not depend on a displacement and a frequency of forcing but friction coefficients is reducing as a clamping force is increasing.

The roof grid of single-layer space frame structure, for Energy Core of Incheon Airport Second Terminal, is very simple and aesthetic, but it is apt to buckle under external force because of mild curvature and complex shape. The object of this study is to estimate the stability of single-layer space frame structures for Energy Core of Incheon Airport Second Terminal with the analytical conditions of structural design. The results show that the buckling load of model(pin-pin, uniform load, rigid joint), that is, the most similar model to the analytical conditions of structural design. was 10.7kN/㎡.

The finite element analysis of large sized rectangular water tank structures made of stainless steel materials is carried out for various combined load cases. The combined load cases for a large size of 5,000ton are further determined using the specification(KS B　6283) established from the Korean Standards Association. For the better numerical efficiency, the rectangular panels are modelled using the ANSYS program. The numerical results obtained for different load cases show as follows. In order to resist the snow load, it takes the influence of the gap than the size of the column. Also, in order to resist the water pressure, it shall increase the thickness of the wall. But, increasing the thickness of the wall is considerably less economical. Therefore, the angle with big thickness should be placed right next to the wall.

유기 발광 다이오드(OLED)는 차세대 조명으로 많은 관심을 받고 있으며, 디스플레이로서의 상용화에 이미 성공하였고, 대체 조명 시장에까지 그 영역을 넓혀가고 있다. OLED의 급격한 기술 발전에도 불구하고, OLED의 유 기층/투명전극과 기판에서 발생하는 내부 전반사에 의해서 일반적인 OLED의 외부 광자 효율은 현재 20~30% 정도에 머무르고 있는 실정이다. 따라서, 고효율의 OLED의 구현을 위해서는 고성능의 광추출 구조의 개발이 절실히 필요하 다. 내부 광추출 구조를 소자에 적용하기 위해서는 많은 어려움이 있으며, 특히 소자의 누설전류를 방지하기 위해서 광추출 구조의 표면 거칠기를 최소화하는 것이 매우 중요하다. 본 연구에서는 ZnO 나노파티클-투명 고분자 복합 구 조의 광추출 구조를 쉬운 제작 방법으로 구현하였으며, 나노파티클의 분산에 따른 광추출 구조의 광학적 특성 및 표 면 구조의 영향에 대해서 알아보았다.

The industrialization and urbanization forced to increase the density of pipelines such as water supply, sewers, and gas pipelines. The materials used for the existing pipe lines are mostly composed of concretes and steels, but it is true that the development for more durable and efficient materials has been continued performed to produce long lasting pipe lines. Recently, underground pipes serve in diverse applications such as sewer lines, drain lines, water mains, gas lines, telephone and electrical conduits, culverts, oil lines, etc. In this paper, we present the result of investigation pertaining to the structural behavior of unplasticized polyvinyl chloride (PVC-U) flexible pipes buried underground. In the investigation of structural behavior such as a ring deflection, pipe stiffness, 4-point bending test, experimental and analytical studies are conducted. In addition, pipe stiffness is determined by the parallel plate loading tests and the finite element analysis. The difference between test and analysis is about 8% although there are significant variations in the mechanical properties of the pipe material. In addition, it was found by the 4-point bending test there is no problem in the connection between the pipes by coupler.

In this paper, we present the result of analytical investigation pertaining to the structural behavior of steel-concrete composite plate girder with arch-type web stiffener. In the arch-type web stiffener located in the compression side of web, infill concrete is cast to strengthen the arch-type stiffener and also to exert resisting force against compression force. This type of composite steel-concrete plate girder bridge is built and is in service. To understand the behavior thoroughly, analytical parametric study was conducted by using the finite element method. As a result it was found that the effect of arch-type stiffener with infill concrete is considerable for the design of such type composite girder bridge.

ABSTRACT PURPOSES: It is desirable for buses to be parallel to the face of the bus shelter at a bus stop. In this way, passengers can safely use the buses without moving into the vehicle area. The study was a review of the current bus bay geometric guidelines, to determine whether they lead buses to stop parallel to the face of the bus shelter by analyzing vehicle trajectory. METHODS : A commercial software program for vehicle trajectory analysis was used under our assumptions about bus dimensions and geometric values. The final position of the bus was analyzed for multiple trajectory simulations, reflecting various geometric alternatives. RESULTS: Within the scope of the study, we concluded that the current design guidelines need to be revised by the design values suggested by the study. CONCLUSIONS : The results of the study suggested alternative design values for bus bay geometry, based on the assumption that buses should be parallel to the face of the bus shelter in order to prevent passengers from moving into the vehicle area.

This paper introduces the Hierarchical Decomposition Mapping Diagram (HDMD) that represents the systematic architecture of axiomatic design. HDMD is composed of the contents of module symbol and the independence/dependence relationship between FRs (Functional Requirements) and DPs (Design Parameters). The examples presented in this paper show the strength of the diagrams in comparison with other studies of systematic architectural representation tools, such as hierarchical diagram, module-junction diagram and system flow diagram.

고분자 정밀여과 멤브레인을 이용한 분리공정은 입자나 콜로이드와 같은 특정 크기 이상의 불순물을 용액 상에서 정제하는데 있어 가장 유용한 방법으로 광범위한 분야에서 적용되고 있다. PSF 고분자 정밀여과막의 내부 구조 개선을 위하여 술폰화된 PSF 고분자 (PSS)를 사용하여 정밀여과막을 제막하였다. PSF와 PSS를 혼용해서 고분자 제막이 가능한 농도 영역을 찾았으며 다양한 농도 범위에서 VIPS 공정 조건이 이루어지도록 고분자 용액의 표면층이 충분한 시간동안 공기와 접촉할 수 있는 조건하에서 생성되어진 멤브레인의 단면 구조 및 투과 성능 변화에 관한 조사를 실시하였다. 내부 단면 구조의 비대칭성을 향상시킬 수 있었으며 기계적 강도와 유량이 향상된 정밀여과막을 제조할 수 있었다.

본 연구에서는 높은 제거성능을 가지는 분리막 개발하기 위해, 상전이법을 이용하여 이중구조의 중공사형 한외여과막을 제조하였다. 방사조건에서 에어갭, 내부응고제를 조절하여 중공사를 제조하였다. 분리막의 단면과 표면 모폴로지는 전계방출형주사현미경(FE-SEM)을 이용하여 관찰 할 수 있었으며, 수투과도와 제거성능 평가는 0.2cm2의 테스트 모듈을 제작하여 각각 측정하였다. 50nm PS latex bead를 이용하여 분리막의 공칭공경을 측정하였다. 측정결과 50nm 이하의 공칭공경을 가지는 것을 확인 할 수 있었으며, 박테리아 제거성능은 log 6 이상의 높은 값을 나타내는 것을 확인하였다.

본 연구에서는 평균입경 0.2, 0.5, 1,7㎛ 크기의 α-알루미나 분말을 이용하여 다공성 α-알루미나 지지체의 기공구조를 조절하고자 하였다. 다공성 α-알루미나 지지체는 슬립캐스팅공법을 이용하여 제조한 후 소결하였으며, 이 때 소결 온도가 지지체의 기공특성에 미치는 영향에 대하여 고찰하였다. 제조된 다공성 α-알루미나 지지체는 수은기공분석기를 이용하여 기공크기 및 기공률 등을 분석하였으며, 단일기체투과장치를 이용하여 기체 투과도를 측정하였다. 그 결과 평균입경 0.2, 0.5, 1.7㎛ 크기의 α-알루미나 분말을 이용하여 제조된 지지체는 각각 80, 130, 200㎚의 기공경을 가졌으며, CO2 단일기체에 대해 각각 1300, 1700, 5000GPU를 나타냈다.

A comparative investigation of structure and performance between integrally asymmetric (IA) and thin film composite (TFC) FO membranes has been conducted. The TFC membranes showed superior water flux than IA CTA-based membranes, especially at alkaline feed and draw solutions. However, AFM results displayed smoother surfaces, resulting in the lower fouling propensity of the IA membranes than the polyamide TFC membranes. XPS data revealed lower oxygen atomic content and higher negatively charge of the active layer and higher fouling tendency of the TFC TCK membrane than the TFC HTI membrane. The TCK membrane prepared on a woven substrate served as a promising membrane for FO. This study suggests that desirable FO membranes require the TCK membrane-like open and thin structure as well as the enhancement of antifouling resistance.

In the present work, a new synthesis method has been reported for preparing high-quality NaA zeolite membrane. The present method involves pressure-driven hydrothermal gel coating method(HGCM) on seeded α-alumina support surface having pores of 0.1 and 0.7μm diameter before the secondary growth process. The experimental data revealed that the high-pressure injection of hydrothermal gel solution on α-alumina support surface helped in the pore filling and thin layer coating of gel particles, which promoted the formation of uniform, defect free, and dense zeolite layer. Pervaporative dehydration experiments were conducted for 50 wt.% ethanol-water mixture at 343K. The NaA zeolite membrane, which was prepared by HGCM process on the 0.7μm support, showed that the high total flux was 4.7 kg m-2h-1 and separation factor was more than >1000.

We developed a positively charged membrane with acid resistance via the introduction of a branched-poly(ethyleneimine) (b-PEI) hydrogel layer onto the surface of a polyethersulfone (PES) membrane, which was achieved by immobilization of b-PEI at the PES membrane surface using cross-linking agent. The combined results of ATR FT-IR, XPS and FE-SEM measurements confirmed that the b-PEI hydrogel layer was successfully coated on the PES NF membrane surface. In particular, the b-PEI hydrogel coated membrane surface had positive charge at whole pH range. The positively charged surface could enhance multivalent ion rejection. As a result, the membrane effectively recovered acid substance under strong acidic condition. Moreover, the selective separation was well preserved after exposure to highly concentrated sulfuric acid solution.

Advances made in membrane technology have to do with either enhancing separation efficiency or improving the permeation flux. Enhancing the separation efficiency, however, inevitably led to reducing the flux, and improving the permeation flux resulted in a loss in the separation efficiency. In this presentation, we suggest multiscale porous membranes with inverse-opal structures that allow for high permeation flux without sacrificing separation efficiency. In order to create the multiscale architectured membranes, primary structure of inverse opal having macropores is first prepared. Then, secondary nanostructures are incorporated to elaborately tune the pore size, tortuosity, and interfacial properties. Finally, the constructed multiscale architectures are utilized for water-treatment or removal or organic molecules.

Block copolymer (BCP) self-assembly has been one of attractive approach for highly size-selective and permeable membranes due to its narrow size distribution and high pore density. We produced a thermally annealed PS-b-PMMA film on a neutral substrate, where the randomly oriented PMMA cylinders were formed between two layers of perpendicular PMMA cylinders at both substrate/polymer and polymer/air interfaces. The PMMA cylinders in the BCP films processed with a selective solvent were swollen for tunable mesoporous UF membrane. The confined swelling of PMMA microdomains in PS matrix resulted in the compaction of PS matrix as well as the shrinkage of PMMA microdomains during the removal of a PMMA-selective solvent.