• Title/Summary/Keyword: Assembly Frame

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Performance of steel beams at elevated temperatures under the effect of axial restraints

  • Liu, T.C.H.;Davies, J.M.
    • Steel and Composite Structures
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    • v.1 no.4
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    • pp.427-440
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    • 2001
  • The growing use of unprotected or partially protected steelwork in buildings has caused a lively debate regarding the safety of this form of construction. A good deal of recent research has indicated that steel members have a substantial inherent ability to resist fire so that additional fire protection can be either reduced or eliminated completely. A performance based philosophy also extends the study into the effect of structural continuity and the performance of the whole structural totality. As part of the structural system, thermal expansion during the heating phase or contraction during the cooling phase in most beams is likely to be restrained by adjacent parts of the whole system or sub-frame assembly due to compartmentation. This has not been properly addressed before. This paper describes an experimental programme in which unprotected steel beams were tested under load while it is restrained between two columns and additional horizontal restraints with particular concern on the effect of catenary action in the beams when subjected to large deflection at very high temperature. This paper also presents a three-dimensional mathematical modelling, based on the finite element method, of the series of fire tests on the part-frame. The complete analysis starts with an evaluation of temperature distribution in the structure at various time levels. It is followed by a detail 3-D finite element analysis on its structural response as a result of the changing temperature distribution. The principal part of the analysis makes use of an existing finite element package FEAST. The effect of columns being fire-protected and the beam being axially restrained has been modelled adequately in terms of their thermal and structural responses. The consequence of the beam being restrained is that the axial force in the restrained beam starts as a compression, which increases gradually up to a point when the material has deteriorated to such a level that the beam deflects excessively. The axial compression force drops rapidly and changes into a tension force leading to a catenary action, which slows down the beam deflection from running away. Design engineers will be benefited with the consideration of the catenary action.

A Basic Study on Plastic Suspension System for Automotive Seat under Consideration of Body Pressure Distribution (체압 분포를 고려한 자동차 시트용 플라스틱 서스펜션에 대한 기초적 연구)

  • Park, Dae-Min;Kim, Key-Sun;Choi, Doo-Seuk;Kim, Sei-Whan;Park, Won-Sik;Cho, Jae-Ung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.11
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    • pp.4751-4755
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    • 2011
  • This study investigates the plastic suspension assembly which is installed on inside of vehicle seat and support passenger's back to supply the comfortable ride performance. It aims to develop the structural design in order to support driver's back uniformly and assemble seat back frame with plastic suspension effectively. The part of suspension is designed by considering the body pressure distribution of driver and it has the same size as the practical model on simulation analysis. It is confirmed that the analysis result of plastic suspension approaches the practical measured values and the better body pressure distribution can be obtained as compared with the existing wire type.

The Law of the 7 Messidor II on Nationales Archives of France - the research against the evolution process at the national Archives of France from the National Assembly records center - (혁명력 2년 메시도르 7일(1794년 6월 25일) 기록보존에 관한 법령연구 -의회 문서보관소에서 국립문서보관소로의 진화과정에 대한 연구-)

  • Jo, Chung-Hyun
    • The Korean Journal of Archival Studies
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    • no.14
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    • pp.289-323
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    • 2006
  • The first organization of the 'national Archives of France' was defined by a law voted during the Revolution, the law of June 25, 1794 which is remained into force during nearly two century-until with the law of January 3, 1979. This law is regarded as the text founder of the national Archives of France, mainly thanks to its article 48 which posed the principle of the free communicability of the whole of the documents of national Archives of France. But it had initially as an aim to organize and frame sortings of the documents gathered in great number since the beginning of the French revolution. Its principal provision does not leave astonish us: it envisaged a separation between the documents to be eliminated, the useful documents has the administration, only intended to be preserved in national Archives of France?, and the documents interesting for the history, which were intended for the national Library.

A Study on the Structure Behavior of Dry-assembled Wall with Concrete Blocks subjected to Cyclic Lateral Load (콘크리트블록으로 건식조립된 벽체의 수평반복하중에 대한 구조거동 연구)

  • Lee, Joong-Won
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.6
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    • pp.440-447
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    • 2020
  • Masonry structures are used as bearing walls in small buildings, but they are generally considered non-bearing walls. They are used as partition walls that divide the interior spaces of the frame structures of buildings. In addition, wetting techniques that use mortar as an adhesive between blocks or bricks in construction are vulnerable to climatic conditions, especially cracks in mortar, which can cause conduction collapse of the walls in seismic loading. The purpose of this research was to propose a dry concrete block construction method that complements the weak axial shear stiffness and improves the weakness of the wet construction method as well as to investigate its structural behavior. In this study, the material properties of concrete blocks were examined, and the seismic performance of the proposed dry assembly structure was verified by structural behavior tests on horizontal cyclic loads. First, in these study results, concrete blocks can be applied to the dry block construction method instead of wet construction methods because they secure more than C-type blocks in KS regulations. Second, the structural performance of the wall against a horizontal cyclic load indicates that the resisting force of the assembly block wall is increased by increasing the horizontal length of the wall, forming several diagonal cracks. Finally, the proposed dry block wall structure requires a seismic performance assessment considering that the ratio of the shape of the wall by height and length is considered a major influence variable on the structural behavior under a horizontal load.

Compensation of Installation Errors in a Laser Vision System and Dimensional Inspection of Automobile Chassis

  • Barkovski Igor Dunin;Samuel G.L.;Yang Seung-Han
    • Journal of Mechanical Science and Technology
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    • v.20 no.4
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    • pp.437-446
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    • 2006
  • Laser vision inspection systems are becoming popular for automated inspection of manufactured components. The performance of such systems can be enhanced by improving accuracy of the hardware and robustness of the software used in the system. This paper presents a new approach for enhancing the capability of a laser vision system by applying hardware compensation and using efficient analysis software. A 3D geometrical model is developed to study and compensate for possible distortions in installation of gantry robot on which the vision system is mounted. Appropriate compensation is applied to the inspection data obtained from the laser vision system based on the parameters in 3D model. The present laser vision system is used for dimensional inspection of car chassis sub frame and lower arm assembly module. An algorithm based on simplex search techniques is used for analyzing the compensated inspection data. The details of 3D model, parameters used for compensation and the measurement data obtained from the system are presented in this paper. The details of search algorithm used for analyzing the measurement data and the results obtained are also presented in the paper. It is observed from the results that, by applying compensation and using appropriate algorithms for analyzing, the error in evaluation of the inspection data can be significantly minimized, thus reducing the risk of rejecting good parts.

Design and Making of a Handmade Vehicle with a Formula in 2016 (2016 포뮬러 형태의 자작자동차 설계 및 제작)

  • Kim, Jin-Seok;Shin, Dae-Soo;Shin, Min-Soo;Kim, Seong Keol
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.26 no.1
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    • pp.82-88
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    • 2017
  • In 2016, a handmade vehicle called to the VF-3 was designed and manufactured as a formula typed car. Prior to manufacturing and assembly, the impact attenuator was analyzed through ANSYS LS-DYNA, and the results were applied to the VF-3. The dynamical performance of the VF-3, such as the acceleration and circling simulations, was also assessed through MSC-ADAMS. The results were applied and compared after the Korean Society of Automotive Engineers (KSAE) competition. There was only a 0.8 s difference in the acceleration test. In order that the frame was not twisted by thermal deformation, Argon-TIG welding was used and a zig was designed. Another zig was designed to have the exact position for the hardpoints in the suspension system. Most of the parts were made with aluminum 7050 for reduced weight. The VF-3 won the third prize in the 2016 KSAE Student Handmade Vehicle competition.

An Inspection System for Measuring Feeding Accuracy of Tape Feeders (테이프 피더의 부품공급 정밀도 측정을 위한 검사 시스템)

  • Jo, Tae-Hun;Lee, Seong-Jun
    • Journal of Institute of Control, Robotics and Systems
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    • v.8 no.7
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    • pp.573-577
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    • 2002
  • A tape feeder of a SMD(Surface Mount Device) mounter is a device that sequentially feeds electronic components on a tape reel to the pick-up system of the mounter. As components are getting much smaller, feeding accuracy of a feeder becomes one of the most important factors for successful component pick-up. Therefore, it is critical to keep the feeding accuracy to a specified level in the assembly and production of tape feeders. This paper describes a tape feeder inspection system that was developed to automatically measure and inspect feeding accuracy using machine vision. It consists of a feeder base, an image acquisition system, and a personal computer. The image acquisition system is composed of CCD cameras with lens, LED illumination systems, and a frame grabber inside the PC. This system loads up to six feeders at a time and inspects them automatically and sequentially. The inspection software was implemented using Visual C++on Windows NT with easily usable GUI. Using this system, we can automatically measure and inspect the quality of all feeders in production process by analyzing the measurement results statistically.

Expression of Hepatitis C Virus Structural Proteins in Saccharomyces cerevisiae

  • LEE JONG-SOO;YU JUNG;SHIN HYUN-JIN;KIM YOUNG-SANG;AHN JEONG-KEUN;LEE CHONG-KIL;POO HARYOUNG;KIM CHUL-JOONG
    • Journal of Microbiology and Biotechnology
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    • v.15 no.4
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    • pp.767-771
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    • 2005
  • Expression in yeast may prove more amenable to generating large amounts of viral antigens for a vaccine candidate. We, therefore, cloned the gene encoding the Hepatitis C virus (HCV) structural proteins (C-El-E2, c740) fused in-frame with, and immediately 3' to, the chicken-lysozyme signal peptide (C-SIG) gene and under the control of the yeast glyceraldehyde-3-phosphate dehydrogenase gene promoter. In yeast, the HCV structural proteins were expressed in two different forms: a processed and a nonprocessed aggregated form. Biophysical characterization by sucrose linear gradient centrifugation revealed that both forms were present in the same fractions with a buoyant density of 1.127-1.176 g/$cm^3$. These findings suggest that the efficient synthesis of HCV structural proteins in yeast may be an important tool to study virus assembly and may lead to the development of an HCV vaccine.

A Study on the Finite Element Analysis of Three Dimensional Plate Structures (3차원 공간 판구조물의 유한요소 해석에 관한 연구)

  • 권오영;남정길
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.35 no.1
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    • pp.54-59
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    • 1999
  • High-speed electronic digital computers have enabled engineers to employ various numerical discretization techniques for solutions of complex problems. The Finite Element Method is one of the such technique. The Finite Element Method is one of the numerical analysis based on the concepts of fundamental mathematical approximation. Three dimensional plate structures used often in partition of ship, box girder and frame are analyzed by Finite Element Method. In design of structures, the static deflections, stress concentrations and dynamic deflections must be considered. However, these problem belong to geometrically nonlinear mechanical structure analysis. The analysis of each element is independent, but coupling occurs in assembly process of elements. So, to overcome such a difficulty the shell theory which includes transformation matrix and a fictitious rotational stiffness is taken into account. Also, the Mindlin's theory which is considered the effect of shear deformation is used. The Mindlin's theory is based on assumption that the normal to the midsurface before deformation is "not necessarily normal to the midsurface after deformation", and is more powerful than Kirchoff's theory in thick plate analysis. To ensure that a small number of element can represent a relatively complex form of the type which is liable to occur in real, rather than in academic problem, eight-node quadratic isoparametric elements are used. are used.

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A Study on the Library Cooperation between South and North for the Unified Korea (통일 한국을 대비한 남북한 도서관교류협력에 관한 연구)

  • Park, Mihyang
    • Journal of the Korean Society for information Management
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    • v.34 no.1
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    • pp.317-340
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    • 2017
  • Non-ideological information exchange and cooperation based on the scholarly and cultural fields would be the most effective project of south and north Korea for gaining the national homogeneity and trust in the long-term perspective. In this context, this study researched the measures on cultural exchange and cooperation between south and north through national libraries for the unified Korea. Related with that issue, this study analyzed function and limitation of national library in north Korea and evaluated library cooperation between south and north Korea in the frame of cultural cooperation project. So, this study suggested the stepwise model of the library cooperation between south and north based on the five practical measures including the cooperation governance system.