• Title/Summary/Keyword: Mode of action

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Dynamic analysis of a magneto-electro-elastic material with a semi-infinite mode-III crack under point impact loads

  • Feng, Wenjie;Liu, Jinxi
    • Structural Engineering and Mechanics
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    • v.27 no.5
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    • pp.609-623
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    • 2007
  • The problem of a semi-infinite magneto-electro-elastically impermeable mode-III crack in a magneto-electro-elastic material is considered under the action of impact loads. For the case when a pair of concentrated anti-plane shear impacts, electric displacement and magnetic induction impacts are exerted symmetrically on the upper and lower surfaces of the crack, the magneto-electro-elastic field ahead of the crack tip is determined in explicit form. The dynamic intensity factors and dynamic energy density factor are obtained. The method adopted is to reduce the mixed initial-boundary value problem, by using the Laplace and Fourier transforms, into three simultaneous dual integral equations, one of which is converted into an Abel's integral equation and the others into a singular integral equation with Cauchy kernel. Based on the obtained fundamental solutions of point impact loads, the solutions of two kinds of different loading cases are evaluated by integration. For some particular cases, the present results reduce to the previous results.

Design of a Swing Up Controller for Inverted Pendulum System (도립진자의 스윙업 제어기 설계)

  • Kwon, Yo-Han;Choi, Won-Ho;Kim, Beom-Soo;Lim, Myo-Taeg
    • Proceedings of the KIEE Conference
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    • 1999.11c
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    • pp.643-645
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    • 1999
  • In experiment, a real inverted pendulum system has state constraints and limited amplitude of input. These problems make it difficult to design a swing-up controller. To overcome these problems, we design a sliding mode controller considering physical behaviour of the inverted pendulum system. This sliding mode controller uses a switching control action to converge along a specified path derived from energy equation from a state around the path to desired states(standing position). And optimal control method is used to guarantee stability at unstable equilibrium position. The designed controller can be applied to all inverted pendulum systems regardless of the values of their parameters. Compared with previous existing controllers, it is simple and easy to tune. Experimental results are given to show the effectiveness of this controller.

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Effect of masonry infilled panels on the seismic performance of a R/C frames

  • Aknouche, Hassan;Airouche, Abdelhalim;Bechtoula, Hakim
    • Earthquakes and Structures
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    • v.16 no.3
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    • pp.329-348
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    • 2019
  • The main objective of this experimental research was to investigate the Seismic performance of reinforced concrete frames infilled with perforated clay brick masonry wall of a type commonly used in Algeria. Four one story-one bay reinforced concrete infilled frames of half scale of an existing building were tested at the National Earthquake Engineering Research Center Laboratory, CGS, Algeria. The experiments were carried out under a combined constant vertical and reversed cyclic lateral loading simulating seismic action. This experimental program was performed in order to evaluate the effect and the contribution of the infill masonry wall on the lateral stiffness, strength, ductility and failure mode of the reinforced concrete frames. Numerical models were developed and calibrated using the experimental results to match the load-drift envelope curve of the considered specimens. These models were used as a bench mark to assess the effect of normalized axial load on the seismic performance of the RC frames with and without masonry panels. The main experimental and analytical results are presented in this paper.

Prediction of Acute Toxicity to Fathead Minnow by Local Model Based QSAR and Global QSAR Approaches

  • In, Young-Yong;Lee, Sung-Kwang;Kim, Pil-Je;No, Kyoung-Tai
    • Bulletin of the Korean Chemical Society
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    • v.33 no.2
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    • pp.613-619
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    • 2012
  • We applied several machine learning methods for developing QSAR models for prediction of acute toxicity to fathead minnow. The multiple linear regression (MLR) and artificial neural network (ANN) method were applied to predict 96 h $LC_{50}$ (median lethal concentration) of 555 chemical compounds. Molecular descriptors based on 2D chemical structure were calculated by PreADMET program. The recursive partitioning (RP) model was used for grouping of mode of actions as reactive or narcosis, followed by MLR method of chemicals within the same mode of action. The MLR, ANN, and two RP-MLR models possessed correlation coefficients ($R^2$) as 0.553, 0.618, 0.632, and 0.605 on test set, respectively. The consensus model of ANN and two RP-MLR models was used as the best model on training set and showed good predictivity ($R^2$=0.663) on the test set.

Sensorless Indirect Field Oriented Control of Two-phase In­duction Motor by Sliding Mode Flux/Speed Observer

  • Kim Sam Young;Park Seong Su;Park Seung Yub
    • Proceedings of the IEEK Conference
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    • 2004.08c
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    • pp.622-627
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    • 2004
  • This paper investigated the speed sensorless indirect vector control of a two-phase induction motor to implement adjustable-speed drive for low-power applications. The sliding mode observer estimates rotor speed. The convergence of the nonlinear time-varying observer along with the asymptotic stability of the controller was analyzed. To define the control action which maintains the motion on the sliding manifold, an 'equivalent control' concept was used. It was simulated and implemented on a sensorless indirect vector drive for 150W two-phase induction motor. The simulation and experimental results demonstrated effectiveness of the estimation method.

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A method and analysis of human-error management of a semiconductor industry (반도체산업에서의 인적오류제어방법 및 연구)

  • Yoon Yong-Gu;Park Peom
    • Journal of the Korea Safety Management & Science
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    • v.8 no.1
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    • pp.17-26
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    • 2006
  • Basis frame-work's base in a semiconductor industry have gas, chemical, electricity and various facilities in bring to it. That it is a foundation by fire, power failure, blast, spill of toxicant huge by large size accident human and physical loss and damage because it can bring this efficient, connect with each kind mechanical, physical thing to prevent usefully need that control finding achievement factor of human factor of human action. Large size accident in a semiconductor industry to machine and human and it is involved that present, in system by safety interlock defect of machine is conclusion for error of behaviour. What is not construing in this study, do safety in a semiconductor industry to do improvement. Control human error analyzes in human control with and considers mechanical element and several elements. Also, apply achievement factor using O'conner Model by control method of human error. In analyze by failure mode effect using actuality example.

Vibration Control of Aerial Vehicles-in the Derricking Action

  • Konishi, Katsunobu;Ukida, Hiroyuki;Uchihara, Isamu
    • 제어로봇시스템학회:학술대회논문집
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    • 1998.10a
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    • pp.141-146
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    • 1998
  • This paper presents a scheme to actively control the vertical vibration of aerial vehicles due to the disturbances such as the sudden change of derricking angle and the external forces by using a small plunger attached to the derricking cylinder. Simulations show that the 1st mode vibration is suppressed efficiently by the proposed method without exciting the higher modes' vibration. Detailed mathematical model of the aerial vehicle, its vibration characteristics, detection method of the 1st mode vibration and the controller design based on the lag-element and the disturbance observer are described.

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A Study on the Application and Concept of Sustainable Community in the Contemporary Architecture and Urban Design (현대 건축 및 도시설계에 있어서 지속가능한 커뮤니티의 개념과 적용에 관한 연구)

  • Kwack, Dong-Wha;Lee, Jeong-Mi
    • Journal of The Korean Digital Architecture Interior Association
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    • v.8 no.2
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    • pp.47-56
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    • 2008
  • The purpose of this study is to arrange the design elements and methods for sustainable community. After made the concept of sustainable community clear in the contemporary architecture and urban design, this study examines rural ecovillage, urban demonstration project, co-housing, new urbanism and urban village, and ecological township as the application modes of sustainable community. Through the cases of the application mode, the design elements for sustainable community were summarized as the followings: the symbiosis system with the nature, permaculture and edible landscape, identity, the technology for saving of resources and energy, the traffic system for the reduction of private motor use, mixed use development, and the housing with diversity. And the design methods for sustainable community were summarized as the followings: strategic planning, visioning, community action planning, workshops and charrette, environmental evaluation, and participation techniques.

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Sensorless Indirect Vector Control of Two-phase Induction Motor by Sliding Mode Flux/Speed Observer (슬라이딩 모드 자속/속도 관측기에 의한 2상 유도전동기의 센서리스 간접 벡터 제어)

  • Kim Sam-Young;Park Seong-Su;Park Seung-Yub
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.54 no.1
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    • pp.40-46
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    • 2005
  • This paper has investigated the speed sensorless indirect vectorcontrol of a two-phase induction motor to implement adjustable-speed drive for low-power applications. The sliding mode observer estimates rotor speed. The convergence of the nonlinear time-varying observer along with the asymptotic stability of the controller has been analyzed. To define the control action which maintains the motion on the sliding manifold, an "equivalent control" concept is used. It has been simulated and implemented on a sensorless indirect vector drive for 150W two-phase induction motor. The simulation and experimental results demonstrate effectiveness of the estimation method.

Growth Responses of Lettuce Seeds Germinated in Aqueous Solutions of Sulfur Dioxide (아황산 수용액에서 발아시킨 상치 종자의 생장반응)

  • 이미순
    • Journal of Plant Biology
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    • v.18 no.4
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    • pp.155-160
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    • 1975
  • Growth responses of lettuce seeds germinated in aqueous solutions of $SO_2$ were investigated for mode of action studies of this gas. The concentration and pH of $SO_2$ solution greatly affected the growth of germinating seeds. Root growth was more sensitive to $SO_2$ than hypocotyl growth. The sensitivity of total seedling growth lay between root and hypocotyl growth. Growth inhibition of germinating seeds appeared more serioius when $SO_2$ was added during the early stage of germination.

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