• Title/Summary/Keyword: Pillars

Search Result 349, Processing Time 0.022 seconds

Stem cell behaviors on periodic arrays of nanopillars analyzed by high-resolution scanning electron microscope images

  • Jihun Kang;Eun-Hye Kang;Young-Shik Yun;Seungmuk Ji;In-Sik Yun;Jong-Souk Yeo
    • Applied Microscopy
    • /
    • v.50
    • /
    • pp.26.1-26.3
    • /
    • 2020
  • The biocompatible polyurethane acrylate (PUA) nanopillars were fabricated by soft lithography using three different sizes of nanobeads (350, 500, and 1000 nm), and the human adipose-derived stem cells (hASCs) were cultured on the nanopillars. The hASCs and their various behaviors, such as cytoplasmic projections, migration, and morphology, were observed by high resolution images using a scanning electron microscope (SEM). With the accurate analysis by SEM for the controlled sizes of nanopillars, the deflections are observed at pillars fabricated with 350- and 500- nm nanobeads. These high-resolution images could offer crucial information to elucidate the complicated correlations between nanopillars and the cells, such as morphology and cytoplasmic projections.

Realization of Robot Maniqulators Using Computer Graphics (컴퓨터 그래픽스를 이용한 로보트 매니퓰레이터의 구현 방법)

  • Jang, Won;Chung, Myung Jin;Bien, Zeungnam
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.24 no.2
    • /
    • pp.207-214
    • /
    • 1987
  • In this paper, we developed a method of describing the structure of robot arms and a systematic way to use it as a robt-design-aid tool. To describe the structure of robot arms, a robot was regarded as a collection of various links in the form of polygonal pillars. With the aid of the homogeneous transformation, a set of commands for describing the information on how all the links in the robot are connected was defined and used in graphically realizing complex link-based structures including robot manipulators.

  • PDF

A Literature Review on Enterprise Architecture: Towards a Research Agenda

  • Sharmistha Kar;Rahul Thakurta
    • Asia pacific journal of information systems
    • /
    • v.31 no.3
    • /
    • pp.296-334
    • /
    • 2021
  • Enterprise Architecture and its management focuses on the integration of business processes and IT infrastructure, and have received considerable attention from the academic and the practice audience. Despite this attention, some lacuna can be observed that questions some of the fundamental pillars of the domain. The current business environment demands in the response to digitalization add to further challenges which call for the need to reconceptualise enterprise architecture to be relevant to the emerging context. We respond to this call by presenting a comprehensive review of the literature concerning enterprise architecture and management to facilitate future work. Our review revealed various facets related to enterprise architecture and enterprise architecture management which we present and discuss here. Further, we also chart out possible areas of future explorations. By doing so, this research lays a foundation for continuing inquiry on enterprise architecture and management, contributing to new knowledge for the field.

Shear strain behaviour due to twin tunnelling adjacent to pile group (군말뚝 기초 하부 병렬터널 굴착 시 전단변형 거동 특성)

  • Subin Kim;Young-Seok Oh;Yong-Joo Lee
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.26 no.1
    • /
    • pp.59-78
    • /
    • 2024
  • In tunnel construction, the stability is evaluated by the settlement of adjacent structures and ground, but the shear strain of the ground is the main factor that determines the failure mechanism of the ground due to the tunnel excavation and the change of the operating load, and can be used to review the stability of the tunnel excavation and to calculate the reinforcement area. In this study, a twin tunnel excavation was simulated on a soft ground in an urban area through a laboratory model test to analyze the behavior of the twin tunnel excavation on the adjacent pile grouped foundation and adjacent ground. Both the displacement and the shear strain of ground were obtained using a close-range photogrammetry during laboratory model test. In addition, two-dimensional finite element numerical analysis was performed based on the model test. The results of a back-analysis showed that the maximum shear strain rate tends to decrease as the horizontal distance between the pillars of the twin tunnel and the vertical distance between the toe of the pile group and the crown of the tunnel were decreased. The impact of the second tunnel on the first tunnel and pile group was decreased as the horizontal distance between the pillars of the twin tunnel was increased. In addition, the vertical distance between the toe of the pile group and the crown of the tunnel had a relatively greater impact on the shear strain results than the horizontal distance of the pillars between the twin tunnels. According to the results of the close-range photogrammetry and numerical analysis, the settlement of adjacent pile group and adjacent ground was measured within the design criteria, but the shear strain of the ground was judged to be outside the range of small strain in all cases and required reinforcement.

A Study on the Architectural Transformation of the Hall of Bhaisajyaguru(Healing) Budda(藥師殿) in Chung Yang Temple(正陽寺) -from the main source of the travelogues on Mt. Kumgang. - (정양사(正陽寺) 약사전의 건축사적 변천 - 금강산 기행문을 중심으로 -)

  • Kang, Pyonghee
    • Journal of architectural history
    • /
    • v.12 no.3
    • /
    • pp.163-179
    • /
    • 2003
  • The records of about 60 travel essays of the Hall of Bhaisajyaguru(Healing) Budda which was built in Chung Yang Temple passed down since 1525. The chronological change of that Hall architecture according to each period was traced upon. The building structure of the Hall of Bhaisajyaguru Budda which has a roundabout way, and 6 pillars inside, sometimes each 6 pillars inside and outside is hexagonal, one story building in Japanese colonial period(picture 3-1) or the present(picture 3-3). The panaromic picture of Chung Yang Temple shows no alterations of the layout of buildings(picture 1-1), in which the Hall of $Praj{\tilde{n}}{\bar{a}}$(般若殿), the main building in the center and the Hall of Bhaisajyaguru(Healing) Budda, three story stone pagoda, stone lighthouse in front of it became the central axis. The Hall of Bhaisajyaguru(Healing) Budda remained as it was until Japanese invasions in 1592 and 1597. However, it was greatly damaged by the flood in 1717. It was newly built by Lee Ha Gon's leading in 1717-1732. At that time, the interior design was changed. With Bhaisajyaguru(Healing) Budda, 53 Buddhas and ${\acute{S}}arira$ of Stone stupa which show itself by the flood in 1717 was located in the image of the Mountain of Chunchuk or Cheontae like Yu Jeom Temple. The doors of this Hall are located in the front and back. In the four walls each, two realistic and cubic buddhism pictures were drawn, The color of those picture was partly taken off in 1671 and repainted in 1714. The new building in 1717-1732 regained its colorful appearance. However, the names written beside each Images of Buddha disappeared. The notable remark in these records is that some of these travel essays in 17th-18th centuries was calling this hexagonal hall as the octagonal one. It is very important records because it means that before 1525 the octagonal hall might have existed. Chung Yang Temple was rebuilt between 1976 and 1985 after the destruction in the Korean War. After the records are carefully read, the full scale excavation about this historic site was not done yet. The interesting issue of the existence of octagonal building will be resolved by the full scale excavation.

  • PDF

Design of Unsupported Rock Pillars in a Room-and-Pillar Underground Structure by the Tributary Area Method and the Pillar Strength Estimation (지류론과 암주 강도의 추정에 의한 주방식 지하구조의 무지보 암주 설계)

  • Chang, Soo-Ho;Lee, Chulho;Choi, Soon-Wook;Hur, Jinsuk;Hwang, Jedon
    • Tunnel and Underground Space
    • /
    • v.24 no.5
    • /
    • pp.335-343
    • /
    • 2014
  • Room-and-pillar mining method is one of the most popular underground mining method in the world. If the room-and-pillar mining method is able to be adopted in civil works, it would be highly probable to reduce underground construction costs and to expand a underground structure in use. Therefore, this study aims to analyze the design procedure of unsupported rock pillars which are indispensable to ensure the stability of a room-and-pillar underground structure. Parametric studies on their key design parameters are also carried out for 125 different kinds of design conditions. From the study, the width of a rock pillar is found to show a linear relationship with its corresponding safety factor. The safety factor of a unsupported rock pillar decreased drastically like a negative exponential function as the ratio of room width to pillar width increases in the same rock strength condition. Based on the parametric studies, a design chart to simply evaluate the geometric design parameters of a unsupported rock pillar satisfying a design safety factor is also proposed in this study.

Characteristics of Al-Pillared Clay Synthesized from Bentonite and the Adsorption Properties for Phosphate Ion (벤토나이트로부터 합성한 Al-층간가교점토의 특성과 인산이온의 흡착성)

  • 황진연;김나영;이효민
    • Journal of the Mineralogical Society of Korea
    • /
    • v.15 no.4
    • /
    • pp.315-327
    • /
    • 2002
  • Al-pillared clay was synthesized by constructing pillars of aluminum oxides at the interlayer of montmorillonite in bentonite. XRD, DTA and chemical analyses of Al-pillared clay were performed to examine mineralogical properties. Batch adsorption experiments were also conducted to determine the adsorption properties of this synthesized clay for phosphate ions. XRD analyses showed that the interlayer space of Al-pillared clay expanded to 18.03 $\AA$ at room temperature and shifted to $17 \AA$ after heating to $550^{\circ}C$. A small change in interlayer space after heating indicates high thermal stability. The interlayer expansion by glycerol was also very small. From DTA analyses, pillared clay showed the characteristic endothermic peaks at 270 and $420^{\circ}C$ , which might be caused by dehydration in framework of pillars between interlayers. Adsorption experiment revealed that Al-pillared clay had an excellent adsorption capacity to the phosphate ions, whereas montmorillonite had very low adsorption capacity to phosphate ions. In phosphate solution concentration up to 300 mg/L, 2 g of pillared clay could uptake almost 100% of phosphate ions from 20 mL of solution. After heat treatment of the phosphate adsorbed pillared clay at 50$0^{\circ}C$ to remove phosphate, the calcined pillared clay could adsorb phosphate ions with a little decreased adsorption efficiency. This fact indicates that Al-pillared clay can be recycled for the adsorption of phosphate ions.

Numerical Study on Vertical Stress Estimation for Panel Pillars at Room and Pillar Mines (주방식 광산의 패널 광주 수직응력 추정을 위한 수치해석 연구)

  • Yoon, Dong-Ho;Song, Jae-Joon
    • Tunnel and Underground Space
    • /
    • v.30 no.5
    • /
    • pp.473-483
    • /
    • 2020
  • This paper examines the vertical stress change concentrated on mine pillar which occurs due to the stress disturbance from opening excavation at room and pillar mine by FLAC3D, a finite difference method (FDM) software. The mesh size combination is decided with a careful consideration of relative error and run-time, then its performance is verified. A series of numerical analyses is conducted and the vertical stress at central pillar was observed for the test cases of 1×1 to 11×11 mine pillars, 40 m to 320 m depth with 40 m difference. The results show that the vertical stress of pillar approaches to the similar value with the value estimated by tributary area theory(TAT) when the development area (NP) is increased or the height of overburden (HOB) is decreased, while it is overestimated in the opposite case. Furthermore, it also represents that the vertical stress factor (VSF) converges to a specific value when the depth is increased whille keeping the development area identical.

A Study of Trade-Off Relationship Between Income Maintenance Programs and Social Services (소득보장과 사회서비스의 교환관계(trade-off) 연구)

  • Moon, Jin Young;Kim, Yun Young
    • Korean Journal of Social Welfare
    • /
    • v.67 no.4
    • /
    • pp.203-226
    • /
    • 2015
  • It is widely accepted that one of the main challenges of the 21st century welfare state is how to harmonize 'Old Welfare, Old Risks' which mostly consists of income maintenance programs with 'New Welfare, New Risks' which actively advances social services. It is in this regard that this paper attempts to define the relationship between the income maintenance programs and social services. For this purpose, it analyses social expenditure of 18 OECD countries during 1980-2006, and subsequently attests, if there is a trade-off relationship between the two, using correlation and Granger panel analysis. It duly concludes that the trade-off relationship between the two is not valid in that the two are better understood as a complementary relationship, not substitute relationship.

  • PDF

The Improvement Direction of Piloti Space for Neighborhood Regeneration of Deteriorated Low-Rise Residential Block (노후 저층주거지 근린재생을 위한 필로티 공간 개선 방향)

  • Yoo, Hae-Yeon;Song, Jun-Yeop;Yang, Ji-Won
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.18 no.10
    • /
    • pp.761-770
    • /
    • 2017
  • The objective of this study is to propose a community facility design for the revitalization of the piloti spaces of deteriorated low-rise residential blocks. For this study, the precedent research and institutional limitations are examined. In addition, this study selected and analyzed a deteriorated low-rise residential block utilizing pilotis. Generally, in this type of residence, 8 to 10 generations live together in multi-family houses and row houses, so it is a type of housing that lacks both public space and parking places. Therefore, we attempted to improve the situation of the communities by making use of the space between the pillars and walls without infringing on the parking places. In addition, we took into consideration the design and arrangement of the piloti by evaluating the inconveniences and needs of the residents through interviews. Specifically, various modules were planned and used to transform the spaces between the pillars of the pillar type piloti structure. This study examined the possibilities offered by various materials and modules, and studied the diverse possibilities that can be offered by changing the modules.