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Process of explosive compaction of internally oxidized powders; Cu-0.15%BeO

  • Moon, J.G.
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2002.10b
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    • pp.447-451
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    • 2002
  • The explosive compaction for processing of electrode material was realized based on axisymmetric loading scheme. The compression of internally oxidized fraction of the alloy Cu-0.15%BeO alloy did not provide a considerable strengthening effect; average microhardness varied from 130 to l50Mpa. The tensile strength comes to 30Mpa. However this method can be applicable to obtain a dense briquette for further extrusion of electrode.

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A Study on the Development and Market Trends of Digital Video Recorder (DVR 시장 동향 및 국내외 개발 현황)

  • Chun, H.S.
    • Electronics and Telecommunications Trends
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    • v.24 no.3
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    • pp.128-138
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    • 2009
  • DVR은 아날로그 감시카메라로 입력된 영상정보를 영상 캡처보드를 통해 디지털 영상 정보로 변환, 압축하여 하드디스크에 저장하는 차세대 CCTV 영상감시 및 저장시스템이다. 본 고에서는 미래 유망산업으로 발돋움하고 있는 영상정보산업의 중추를 이루고 있는 DVR의 특성, 시장동향, 국내외 개발현황을 살펴보고 결론에서 정책적 시사점을 도출하고자 한다.

Review of design parameters for FRP-RC members detailed according to ACI 440.1R-06

  • Jnaid, Fares;Aboutaha, Riyad
    • Computers and Concrete
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    • v.11 no.2
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    • pp.105-121
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    • 2013
  • This paper investigates the parameters that control the design of Fiber Reinforced Polymer (FRP) reinforced concrete flexural members proportioned following the ACI 440.1R-06. It investigates the critical parameters that control the flexural design, such as the deflection limits, crack limits, flexural capacity, concrete compressive strength, beam span and cross section, and bar diameter, at various Mean-Ambient Temperatures (MAT). The results of this research suggest that the deflection and cracking requirements are the two most controlling limits for FRP reinforced concrete flexural members.

Analysis of wave motion in an anisotropic initially stressed fiber-reinforced thermoelastic medium

  • Gupta, Raj Rani;Gupta, Rajani Rani
    • Earthquakes and Structures
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    • v.4 no.1
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    • pp.1-10
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    • 2013
  • The present investigation deals with the analysis of wave motion in the layer of an anisotropic, initially stressed, fiber reinforced thermoelastic medium. Secular equations for symmetric and skew-symmetric modes of wave propagation in completely separate terms are derived. The amplitudes of displacements and temperature distribution were also obtained. Finally, the numerical solution was carried out for Cobalt and the dispersion curves, amplitudes of displacements and temperature distribution for symmetric and skew-symmetric wave modes are presented to evince the effect of anisotropy. Some particular cases are also deduced.

Geometrically nonlinear analysis of plane frames composed of flexibly connected members

  • Gorgun, H.
    • Structural Engineering and Mechanics
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    • v.45 no.3
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    • pp.277-309
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    • 2013
  • Beam-to-column connections behaviour plays an important role in the analysis and design of steel and precast concrete structures. The paper presents a computer-based method for geometrically nonlinear frames with semi-rigid beam-to-column connections. The analytical procedure employs modified stability functions to model the effect of axial force on the stiffness of members. The member modified stiffness matrix, and the modified fixed end forces for various loads were found. The linear and nonlinear analyses were applied for two planar steel structures. The method is readily implemented on a computer using matrix structural analysis techniques and is applicable for the efficient nonlinear analysis of frameworks.

Exact solutions of the piezoelectric transducer under multi loads

  • Zhang, Taotao;Shi, Zhifei
    • Smart Structures and Systems
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    • v.8 no.4
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    • pp.413-431
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    • 2011
  • Under the external shearing stress, the external radial stress and the electric potential simultaneously, the piezoelectric hollow cylinder transducer is studied. With the Airy stress function method, the analytical solutions of this transducer are obtained based on the theory of piezo-elasticity. The solutions are compared with the finite element results of Ansys and a good agreement is found. Inherent properties of this piezoelectric cylinder transducer are presented and discussed. It is very helpful for the design of the bearing controllers.

Free vibrations of circular arches with variable cross-section

  • Wilson, James F.;Lee, Byoung Koo;Oh, Sang Jin
    • Structural Engineering and Mechanics
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    • v.2 no.4
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    • pp.345-357
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    • 1994
  • The differential equations governing free, in-plane vibrations of linearly elastic circular arches with variable cross-sections are derived and solve numerically for quadratic arches with three types of rectangular cross sections. Frequencies, mode shapes, cross-sectional load distributions, and the effects of rotatory inertia on frequencies are reported. Experimental measurements of frequencies and their corresponding mode shapes agree closely with those predicted by theory. The numerical methods presented here for computing frequencies and mode shapes are efficient and reliable.

On Beck's column with shear and compressibility

  • Cveticanin, L.J.;Atanackovic, T.M.
    • Structural Engineering and Mechanics
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    • v.6 no.7
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    • pp.747-756
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    • 1998
  • In this paper the influence of rotary inertia, shear and compressibility on the value of the critical force for the Beck's column is analyzed. The constitutive equation is of Engesser's type. As a result, the critical load parameter for which instability of flutter type occurs is calculated for several values of the column's parameters.

Analysis of unreinforced masonry (URM) walls and evaluation of retrofitting schemes for URM structures

  • Mehta, Sanjay;Saadeghvaziri, M.A.
    • Structural Engineering and Mechanics
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    • v.6 no.7
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    • pp.801-815
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    • 1998
  • An overview of an analytical model to predict mortar joint failure in unreinforced masonry (URM) structures is presented. The validity of the model is established by comparison with experimental results at element level as well as structure level. This model is then used to study the behavior of URM walls and two commonly used retrofitting schemes. Finally, effectiveness of the two retrofitting schemes in increasing strength and stiffness of existing URM walls is discussed.

Out-of-plane vibration of multi-span curved beam due to moving loads

  • Wang, Rong-Tyai;Sang, Yiu-Lo
    • Structural Engineering and Mechanics
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    • v.7 no.4
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    • pp.361-375
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    • 1999
  • This paper presents an analytic method of examining the out-of-plane vibration of continuous curved beam on periodical supports. The orthogonality of two distinct sets of mode shape functions is derived. The forced vibration of beam due to moving loads is examined. Two types of moving loads, which are concentrated load and uniformly distributed load, are considered. The response characteristics of beam induced by these loads are investigated as well.