• Title/Summary/Keyword: $^{211}At$

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Effects of modelling on the earthquake response of asymmetrical multistory buildings

  • Thambiratnam, David P.
    • Structural Engineering and Mechanics
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    • v.2 no.2
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    • pp.211-225
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    • 1994
  • Responses of asymmetrical multistorey buildings to earthquakes are obtained by quasi-static code approach and real time dynamic analysis, using two different structural models. In the first model, all vertical members are assumed to be restrained at the slab levels and hence their end rotations, about horizontal axes, are taken as zero. In the second model this restriction is removed and the rotation is assumed to be proportional to the lateral stiffness of the member. A simple microcomputer based procedure is used in the analyses, by both models. Numerical examples are presented where results obtained from both the models are given. Effects of modelling on the response of three buildings, each with a different type and degree of asymmetry, are studied. Results for deflections and shear forces are presented and the effects of the type of model on the response are discussed.

Microstructures fo Top Seed Milt-Processed $YBa_{2}$$Cu_{3}$$O_{7-\delta}$ Superconductor (종자결정법으로 성장시킨 $YBa_{2}$$Cu_{3}$$O_{7-\delta}$ 고온초전도체의 미세구조)

  • 한영희;성태현;한상철;이준성;정상진
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 1999.02a
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    • pp.43-46
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    • 1999
  • The microstructure of Top Seed Milt-Processed $YBa_{2}$$Cu_{3}$$O_{7-\delta}$ single crystal was studied. It was presumed that the segregation of Y211 is due to the difference of growth rates between a, b axis and c axis in crystal direction. Corn kernel lide structure which was grown by the diffusion of Y211 was observed. At the near corner of the seed crystal, the diagonal line on Y123 cry crystal is formed by the corn kernel like structure.

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An investigation into structural behaviour of modular steel scaffolds

  • Yu, W.K.
    • Steel and Composite Structures
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    • v.4 no.3
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    • pp.211-226
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    • 2004
  • This paper presents a study on the structural behaviour of modular steel scaffolds through both experimental and numerical investigations. Three one-storey and three two-storey modular steel scaffolds were built and tested to failure in order to examine the structural behaviour of typical modular steel scaffolds. Details of the tests and their test results were presented in this paper. Moreover, an advanced non-linear analysis method was employed to evaluate the load carrying capacities of these scaffolds under different support conditions. Comparisons between the experimental and the numerical results on the structural behaviour of these modular steel scaffolds were also presented. Moreover, the restraining effects of external supports in practical situations were also studied through finite element methods. The predicted load carrying capacities and deformations at failure of these models under partially restrained conditions were found to be close to the experimental results. A codified design method for column buckling with modified slenderness ratios was adopted for practical design of modular steel scaffolds.

Effect of Ambient Conditions on the Soot Generation of Decane Fuel Droplet (분위기 조건이 Decane 액적의 Soot 생성에 미치는 영향)

  • Lim, Young Chan;Suh, Hyun Kyu
    • Journal of ILASS-Korea
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    • v.19 no.4
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    • pp.211-215
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    • 2014
  • The main purpose of this study is to provide basic information of droplet soot generation of decane fuel. To achieve this, this paper presents the experimental results on the decane droplet combustion conducted under various ambient pressure($P_{amb}$), and oxygen concentration($O_2$) conditions. At the same time, the experimental study was conducted in terms of soot volume fraction($f_v$) and its maximum value. Also, visualization of single fuel droplet was conducted by high resolution CCD camera and ambient pressure($P_{amb}$) and oxygen concentration($O_2$) was changed by control system. It was revealed that higher ambient pressure($P_{amb}$), and oxygen concentration($O_2$) enhanced the soot generation and improved the maximum soot volume fraction( $f_v$).

Security Analysis of AES-CMAC Applicable to Various Environments (다양한 환경에 적용 가능한 AES-CMAC에 대한 안전성 분석)

  • Jeong, Ki-Tae
    • Journal of Advanced Navigation Technology
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    • v.16 no.2
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    • pp.211-218
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    • 2012
  • In this paper, we propose a fault injection attack on AES-CMAC, which is defined by IETF. The fault assumption used in this attack is based on that introduced at FDTC'05. This attack can recover the 128-bit secret key of AES-CMAC by using only small number of fault injections. This result is the first known key recovery attack result on AES-CMAC.

Cutting performance of Cr-Al-Si-N micro end-mill tool deposited by a hybrid coatings (하이브리드 코팅에 의한 Cr-Al-Si-N 마이크로 엔드밀공구의 가공성능)

  • Gang, Myeong-Chang;Sin, Seok-Hun;Kim, Min-Uk;Tak, Hyeon-Seok;Kim, Gwang-Ho;Kim, Jeong-Seok
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2009.05a
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    • pp.211-211
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    • 2009
  • 높은 이온화율과 복잡한 형상의 모재에도 표면 도포성 및 균일성을 나타내는 아크이온플래이팅 기술과 비전도성 세라믹 타겟물질에 적용가능한 스퍼터링 기술이 결합된 하이브리드 코팅 시스템(Hybrid coating system)을 이용하였다. 그리고 Cr-Al-N과 Cr-Si-N 코팅막의 강화 기구를 복합시킨 새로운 개념의 Cr-Al-Si-N 코팅막을 초경(WC-Co)시험편에 증착하여 Si 첨가량에 따른 미세구조의 미세경도 특성을 파악하였다. 공구성능 평가는 고속가공조건하에 마이크로 밀링기에서 무코팅(초경공구), Cr-Al-Si-N (Si : 0, 4.5, 8.7, 16 at.%) 코팅 마이크로엔드밀에 대하여 공구마멸에 대한 공구수명을 비교, 평가하였다.

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Tests to Detect Changes in Micro-Flora Composition;

  • Kim, Donguk;Yang, Mark C.K.
    • Communications for Statistical Applications and Methods
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    • v.10 no.1
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    • pp.211-224
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    • 2003
  • Good's lambda test, a permutation test used to detect the changes of microorganism composition under two pathological conditions, has been quite popular for studying the micro-flora responsible for periodontal disease. A vast number of different micro-flora in the mouth renders the traditional chi-square test inapplicable. The main purpose of this paper is to evaluate the power of this test so that the sample size can be determined at the design stage. The robustness of this test and its comparison to two other intuitive tests are also presented. It is found that a permutation test based on likelihood ratio is more powerful than the lambda test in our simulated cases.

The Future of Planetary Entry Technology

  • Park, Chul
    • International Journal of Aeronautical and Space Sciences
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    • v.12 no.3
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    • pp.211-224
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    • 2011
  • This is a written version of an hour-long lecture delivered by the author on June 30, 2011, as Plasmadynamics and Lasers Award Lecture at the AIAA 2011 summer conference in Honolulu, Hawaii. The author proposes that two areas of planetary entry physics be pursued in the future: outer planet aero-capturing and study of aerodynamics of meteoroid entries, both for the purpose of advancing the understanding of the possible extraterrestrial seeding of building blocks of life. For outer planet aero-capturing, the author proposes to develop new shock tube facilities that will produce up to 30 km/s of shock speed without causing photo-ionization of the driven gas by the radiation from the hot driver gas. Regarding meteors, the author proposes to carry out laboratory testing of the Tunguska event and of the seeding of amino acid molecules using a ballistic range which shoots a snowball laden with amino acid molecules toward a water surface.

Analytical approximate solutions for large post-buckling response of a hygrothermal beam

  • Yu, Yongping;Sun, Youhong
    • Structural Engineering and Mechanics
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    • v.43 no.2
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    • pp.211-223
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    • 2012
  • This paper deals with large deformation post-buckling of a linear-elastic and hygrothermal beam with axially nonmovable pinned-pinned ends and subjected to a significant increase in swelling by an alternative method. Analytical approximate solutions for the geometrically nonlinear problem are presented. The solution for the limiting case of a string is also obtained. By coupling of the well-known Maclaurin series expansion and orthogonal Chebyshev polynomials, the governing differential equation with sinusoidal nonlinearity can be reduced to form a cubic-nonlinear equation, and supplementary condition with cosinoidal nonlinearity can also be simplified to be a polynomial integral equation. Analytical approximations to the resulting boundary condition problem are established by combining the Newton's method with the method of harmonic balance. Two approximate formulae for load along axis, potential strain for free hygrothermal expansion and periodic solution are established for small as well as large angle of rotation at the end of the beam. Illustrative examples are selected and compared to "reference" solution obtained by the shooting method to substantiate the accuracy and correctness of the approximate analytical approach.