• Title/Summary/Keyword: Passive structure

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The Effect of a Compressive Follower Pre-load on the Ligament of Lumbar Spine and the Relationship with Low Back Pain (압축 종동 예하중이 요추 인대에 미치는 영향과 요통과의 관계)

  • Moon, Chang-Hyun;Chung, Tae-Eun;Sin, Hyo-Chol
    • Transactions of the Korean Society of Automotive Engineers
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    • v.18 no.6
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    • pp.63-69
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    • 2010
  • A noble model of the whole lumbar spine (L1~L5) considering all the passive elements, especially the ligaments of the lumbar spine was developed. The purpose of this study was to investigate the relationship between the shear stress of the AVB and the ALL and the effect of a compressive follower pre-load on all ligaments with various motions. The result shows that the shear stress at the AVB and the ALL are positively correlated. This indicates that the shear stress of the ligament can be used an index of low back pain. Regarding the effect of a follower pre-load, contrary to our expectation, the shear stress of the ligaments was not always reduced by applying follower pre-load; flexion was decreased and axial rotation did not change, while extension and lateral bending were increased.

Seismic performance and optimal design of framed underground structures with lead-rubber bearings

  • Chen, Zhi-Yi;Zhao, Hu;Lou, Meng-Lin
    • Structural Engineering and Mechanics
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    • v.58 no.2
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    • pp.259-276
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    • 2016
  • Lead-rubber bearings (LRBs) have been used worldwide in seismic design of buildings and bridges owing to their stable mechanical properties and good isolation effect. We have investigated the effectiveness of LRBs in framed underground structures on controlling structural seismic responses. Nonlinear dynamic time history analyses were carried out on the well-documented Daikai Station, which collapsed during the 1995 Hyogoken-Nanbu earthquake. Influences of strength ratio (ratio of yield strength of LRBs to yield strength of central column) and shear modulus of rubber on structural seismic responses were studied. As a displacement-based passive energy dissipation device, LRBs reduce dynamic internal forces of framed underground structures and improve their seismic performance. An optimal range of strength ratios was proposed for the case presented. Within this range, LRBs can dissipate maximum input earthquake energy. The maximum shear and moment of the central column can achieve more than 50% reduction, whereas the maximum shear displacement of LRBs is acceptable.

Evaluation of the seismic performance of off-centre bracing system with ductile element in steel frames

  • Bazzaz, Mohammad;Kheyroddin, Ali;Kafi, Mohammad Ali;Andalib, Zahra
    • Steel and Composite Structures
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    • v.12 no.5
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    • pp.445-464
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    • 2012
  • In order to evaluate the dynamic behavior of passive energy dissipation system, two steps need to be considered for prediction of structural response in the presence of ductile element in an off-centre bracing system. The first is a detailed analysis of the proposed ductile element and the second is the effect of this ductile element on an off-centre bracing system. The use of ductile bracing system is expanding in steel structures in order to increase the force reduction factor. Therefore, regarding the nonlinear behavior of steel material used in an off-centre bracing systems and using ductile element in OBS bracing systems, the seismic evaluation of the mentioned systems seems to be necessary. This paper aims to study linear and nonlinear behavior of steel frames with off-centre bracing system and ductile element, in order to get the best position of these bracing elements. To achieve this purpose, the modeling has been done with ANSYS software. The optimum eccentricity has been obtained by modeling three steel frames with different eccentricities and evaluating the results of them. The analytical results showed that the model OBS-C with 0.3 eccentricities has higher performance among the models.

Study on dielectric properties of $Ba_{0.5}Sr_{0.5}TiO_{3}$thin films for high-frequency passive device (고주파 수동소자 유전체용 $Ba_{0.5}Sr_{0.5}TiO_{3}$ 박막의 유전특성에 관한 연구)

  • 이태일;최명률;박인철;김홍배
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.263-266
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    • 2001
  • In this paper, we investigated dielectric properies for BST thin films that was deposited on MgO/Si substrates using RF magnetron sputtering. In here, MgO film was used to perform that a diffusion b arrier between the BST film and Si substrate and a buffer layer to assist the BST film growth. A d eposition condition for MgO films was RF Power of 50W, substrate temperature of room temperature and the working gas ratio of Ar:O$_2$ were varied from 90:10 to 60:47. Finally we manufactured the cap acitor of Al/BST/MgO/Si/Al structure to know electrical properties of this capacitor through I-V, C-V measurement. In the results, C-V aha racteristic curves was shown a ferroelectric property so we measured P-E. A remanent poliazation and coerceive electric field was present 2$\mu$C/cm$^2$ and -27kV/cm respectively at Ar:O$_2$=90:10. And a va clue of dielectric constant was 86 at Ar:02=90:10.

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On the Fantastic Aspect in Electronic Media Art : A Preliminary Approach by Way of Barthes, Freud and Lyotard (전자매체예술에서의 '환상적' 측면에 대하여: 바르트, 프로이트, 리오타르를 경유한 접근)

  • Kim Won-Bang
    • Journal of Science of Art and Design
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    • v.5
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    • pp.159-174
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    • 2003
  • 'Fantasy', the central notion of this essay, is discussed here more as a new paradigm in order to describe the structure of a work of art than as a stylistic characteristic proper to a specific genre of art. It means the whole situation and experience produced by two connected terms 'corporeal subject - screen'. Roland Barthes explained the 'semiographic painting' by Andre Masson as a field in which happens a certain connexion between the impulse of subject and the image, which views the painting not as a physical object but as a 'cinematic screen' ; painting may be redefined as a dream or a fantasy of the corporeal subject. And such an idea of 'art as fantasy' is closely related to the recent theoretical attempts consisting in abolishing the vision-centered conception of art since Renaissance. In this essay, the notion of fantasy as an aesthetic model is sketched by means of the Freud's notes on the fantasy 'A child is being beaten' and Lyotard's more advanced analyse on its attributes and operations. In Lyotard's analysis, fantasy is defined as a 'bloc' or a 'matrix-figure' featuring simultaneous conversion between the active and the passive, sadism and masochism, and coexistence of imcompossible meanings. In this sense, fantasy may be given to us as an analogical model from which we can outline the aesthetic characteristics of electronic media art involving virtual reality and interactivity.

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Studies on MMIC oscillator using HBT for X-band (X-band용 MMIC 오실레이터 설계연구)

  • Chae, Yeon-Sik;An, Dan;Rhee, Jin-Koo
    • Proceedings of the IEEK Conference
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    • 1998.06a
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    • pp.387-390
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    • 1998
  • In this paper, HBT's with lower phase noise and passive elements, such as resistors, capacitors and inductors, for resonance and impedance matching networks are designed, fabricated, tested, and carefully analysed, respectively, and then, they are integrated for the design and fabrication of functional X-band oscillators with lower phase noise. Epi-wafers for HBT's with the structure of graded $Al_{x}$G $a_{1-x}$ As emitter and C-doped base layer of 700.angs. thick were used to specially emphasize the improvement of $f_{T}$ and $f_{max}$, and the lowering of phase noise, in design aspects. At the test frequencies of 12GHz, capacitances of MIM capacitors, spiral inductor, and resistances are 0.5~10pF, 0.4~11.06nH, and 20~1,380.ohm., respectively. The emitter size of HBY's for the X-band MMIC oscillators is 3*10u $m^{2}$, and find chip size is 0.9*0.9m $m^{2}$..EX>.

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A Study on the Dispositional Structure of Kyungsang Provincial Government Office (KamYoung) in the late 19th century (19세기말(世紀末) 경상감영건축(慶尙監營建築)의 배치구성(配置構成)에 관한 연구(硏究))

  • Cho, Young-Wha
    • Journal of architectural history
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    • v.9 no.2 s.23
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    • pp.33-48
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    • 2000
  • This study aims to analyze the construction of Kyungsang KAMYOUNG in the late Chosun dynasty by restoring its constructive system and relating it with the office organization. followings are the summary of this study. 1. Government office of Daegu consists of inn(KAEGSA), Kyungsang KAMYOUNG, and Daegu city hall(BUA), and JINYOUNG. 2. The layout of virtual placement is shown in the in the text. Even though it had been newly constructed due to three times of fire, the fundamental scheme of space is found out not to have been changed since mid-eighteen century at the latest. 3. Followings are the result of analyzing the space of KAMYOUNG, after dividing its space into entry area, main business area and police military business area in the aspect of business. First, entry area consists of 2 door system with external door(UOISAMMUN) and internal door(NAESAMMUN). Second, main business area consists of facilities for inspector, public officials, and low grade employee respectively This space is divided into SUNHWADANG area and JINGCHONGKAK area, and the former consists of active business facilities, and the latter consists of passive business facilities focusing on the rest facilities. Third, business support area consists of facilities for low grade employee and minor assistant respectively, which are placed to the left and right of POJONGMUN and KWANPUNGRU. Fourth, police military business space is in middle(JUNGYOUNG) and forms separate areas to the east of SUNHWADANG. Accordingly, It is certain that the space of Kyungsang KAMYOUNG had been placed in accordance with the nature of business per position.

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Simultaneous Optimum Design of Hybrid Structural Control System (복합구조제어시스템의 동시최적설계)

  • 박관순;고현무
    • Journal of the Earthquake Engineering Society of Korea
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    • v.6 no.5
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    • pp.37-43
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    • 2002
  • In this paper, an integrated optimum design method for hybrid structural control system is studied. Not only the distribution and the capacity of passive devices but also those of active devices, and the controllers are treated as design variables in the proposed approach. Multi-objective optimization problem is formulated by using the preference function, which is newly defined in this study. Genetic algorithm is adopted as a numerical searching technique in order to simultaneously find the optimum solutions. The validity of the proposed method is verified through the example designs and the numerical simulations of an earthquake excited multi-degrees-of-freedom structure.

Characterization of Embedded Thick Film Capacitor in LTCC Substrate (유전체 Paste를 이용한 LTCC 내장형 후막 Capacitor 제작 및 평가)

  • Cho, Hyun-Min;Yoo, Myung-Jae;Park, Sung-Dae;Lee, Woo-Sung;Kang, Nam-Kee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07b
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    • pp.760-763
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    • 2003
  • Low Temperature Cofired Ceramics (LTCC) technology is a promising technology to integrate many devices in a module by embedding passive components. For the module substrate, most LTCC structures have dielectric constants below 10 to reduce signal delay time. Some components, which need high dielectric constants, have not been yet embedded in LTCC module. So, embedding capacitor with high capacitance by applying another dielectrics with high dielectric constants in LTCC is an important issue to maximize circuit density in LTCC module. In this study, electrical properties of embedded capacitor fabricated by dielectric paste of high dielectric constants (K-100) and co-firing behavior with LTCC were investigated. To prevent camber development of co-fired structure, constrained sintering process was tested. Dielectric properties of embedded capacitors were calculated from their capacitance and impedance value. Temperature coefficient of capacitance were also measured.

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Current Versus Voltage Characteristics of a Si Based 1-Diode Type Resistive Memory with Cr-SrTiO3 Films (Cr-SrTiO3 박막을 이용한 Si 기반 1D 형태 저항 변화 메모리의 전류-전압 특성 고찰)

  • Song, Min-Yeong;Seo, Yu-Jeong;Kim, Yeon-Soo;Kim, Hee-Dong;An, Ho-Myoung;Kim, Tae-Geun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.24 no.11
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    • pp.855-858
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    • 2011
  • In this paper, in order to suppress unwanted current paths originating from adjacent cells in a passive crossbar array based on resistive random access memory (RRAM) without extrinsic switching devices, 1-diode type RRAM which consists of a 0.2% chromium-doped strontium titanate (Cr-$SrTiO_3$) film deposited on a silicon substrate, was proposed for high packing density, and intrinsic rectifying characteristics from the current versus voltage characteristics were successfully demonstrated.