• Title, Summary, Keyword: Eccentricity

Search Result 829, Processing Time 0.038 seconds

A Study on the Relationship between Earthquake Damage and the Design Eccentricity of Building with Planar Irregularity (평면 비정형 건물의 설계편심과 지진 손상도의 상관관계에 관한 연구)

  • Lee, Kwang Ho;Jeong, Seong Hoon
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.17 no.5
    • /
    • pp.237-243
    • /
    • 2013
  • In the Korean Building Code (KBC), the Design Eccentricity involves the torsional amplification factor (TAF), and the inherent and accidental eccentricities. When a structure of less than 6-stories and assigned to seismic design category C or D is designed using equivalent static analysis method, both KBC-2006 and KBC-2009 use the TAF but apply different calculation methods for the of design eccentricity. The design eccentricity in KBC-2006 is calculated by multiplying the sum of inherent eccentricity and accidental eccentricity at each level by a TAF but that in KBC-2009 is calculated by multiplying only the accidental eccentricity by a TAF. In this paper, the damage indices of a building with planar structural irregularity designed by different design eccentricities are compared and the relationship between the earthquake damage and design eccentricity of the building is evaluated. On the basis of this study, the increment of design eccentricity results in the decrement of final eccentricity and global damage index of structure. It is observed that design eccentricity in KBC-2006 reduces the vulnerability of torsional irregular building compared to design eccentricity in KBC-2009.

A Study on a Lane Detection Using Eccentricity (Eccentricity를 이용한 차선 검출에 관한 연구)

  • Jeong, Tae-Il;Arshad, Nasim;Moon, Kwang-Seok;Kim, Jong-Nam
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.16 no.12
    • /
    • pp.2755-2761
    • /
    • 2012
  • In this paper, a lane detection algorithm using Eccentricity calculation is proposed. Lane detection is used for lane departure warning which can support safe driving to prevent accidents. In other to enhance the detection rate, we define the Eccentricity calculation which is introduced in graph theory, and evaluate the Eccentricity. The Eccentricity for any straight line is equal to 1, hence computing the Eccentricity allows the implementation of a first order equation. As a results of simulation, we confirmed that the proposed algorithm was enhanced by time and space complexity, and superior to the performance of the conventional lane detections.

A study on roll eccentricity controller of hot rolling mill (열간 압연기의 롤 편심 제어기에 관한 연구)

  • 지창운
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.1480-1483
    • /
    • 1996
  • A set of approaches suggested to control the eccentricity is discussed in this paper. Among these, filter-integrator method is used to design the controller, which also includes the input signal synchronization, stabilizing filter and eccentricity source discrimination. Using the S/W that is coded for real time application of that controller, we simulated the operations of that one. The simulation results show the characteristics of eccentricity compensation and eccentricity discrimination. However, from these results, we can see that only proper stabilization strategy certificates the safe eccentricity control.

  • PDF

Thickness Control of Cold-Rolling Mills with Roll Eccentricity (롤편심을 포함한 냉간 압연시스템의 두께제어)

  • 김승수;김종식;황이철
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • /
    • pp.248-254
    • /
    • 1996
  • A disturbance rejection controller using eccentricity filtering and LQ control techniques is proposed to alleviate significantly the effect of roll eccentricity in multivariable cold-rolling processes. Fundamental problems such as process time delay inherent in exit thickness measurement and non-stationary characteristics of roll eccentricity signals can be overcome by the proposed control method. The filtered instantaneous estimate of roll eccentricity may be exploited to improve instantaneous estimate of the exit thickness variation based on roll force and roll gap mearsurements, and a feedforward compensator is augmented as a reference for a gaugemeter thickness estimator. And, LQ feedback controller is combined with eccentricity filter for the attenuation of the exit thickness variation due to the entry thickness variation. The simulation results show that eccentricity components have been significantly eliminated and simultaneously other distrubances also have been attenuated.

  • PDF

Inductances Evaluation of a Squirrel-Cage Induction Motor with Curved Dynamic Eccentricity

  • Lv, Qiang;Bao, Xiaohua;He, Yigang;Fang, Yong;Cheng, Xiaowei
    • Journal of Electrical Engineering and Technology
    • /
    • v.9 no.5
    • /
    • pp.1623-1631
    • /
    • 2014
  • Eccentricity faults more or less exist in all rotating electrical machines. This paper establishes a more precise model of dynamic eccentricity (DE) in electrical machines named as curved dynamic eccentricity. It is a kind of axial unequal eccentricity which has not been investigated in detail so far but occurs in large electrical machines. The inductances of a large three-phase squirrel-cage induction machine (SCIM) under different levels of curved DE conditions are evaluated using winding function approach (WFA). These inductances include the stator self and mutual inductances, rotor self and mutual inductances, and mutual inductances between stator phases and rotor loops. A comparison is made between the calculation results under curved DE and the corresponding pure DE conditions. It indicates that the eccentricity condition will be more terrible than the monitored eccentricity based on the conventional pure DE model.

Analysis of Eccentricity Ratio in the Rolling Piston Type Rotary Compressor Using Mobility Method (모빌리티법을 이용한 롤링피스톤형 회전식 압축기의 축심궤적 해석)

  • 강태식;최동훈;이세정
    • Tribology and Lubricants
    • /
    • v.17 no.1
    • /
    • pp.22-27
    • /
    • 2001
  • This paper presents an analysis of eccentricity ratio of rolling piston using mobility method which is a powerful tool for analyzing dynamically-loaded journal bearings with efficiency and applicability. And, we investigate influences of design parameters (discharge pressure, radial clearance, rotational velocity of shaft, and eccentricity of compressor) on bearing load and eccentricity ratio. The results show that the discharge pressure, radial clearance and rotational velocity of shaft have significant influence on eccentricity ratio, and the discharge pressure and eccentricity of compressor have influence on bearing load.

A Study on the Roll Eccentricity Estimation by Using an ALE

  • Cho, Kyu-Young;Kim, Sang-Woo;Lee, Young-Kow;Jo, Sung-Eun
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.180.2-180
    • /
    • 2001
  • In the hot rolling process, the RF AGC (Roll Force Auto Gauge Control) is used to control the roll gap to reduce the variation of rolling force caused by the roll eccentricity and the variation of material thickness. However the effect of the roll eccentricity cannot be distinguished. To eliminate the effect of the roll eccentricity, the roll eccentricity estimation is needed to supplement some drawbacks of RF AGC. In this paper, an ALE(Adaptive Line Enhancer) that extracts the rolling force variation due to the roll eccentricity is suggested. We also provide an algorithm that enhances the convergence time of roll eccentricity estimation. The performance improvement of the Suggested algorithm is shown via simulations.

  • PDF

Correction of Error due to Hole Eccentricity in Hole-drilling Method Using Neural Network (신경망 기법을 이용한 구멍뚫기법에서의 구멍 편심오차 보정)

  • Kim, Cheol;Yang, Won-Ho;Cho, Myoung-Rae;Heo, Sung-Pil
    • Proceedings of the KSME Conference
    • /
    • /
    • pp.412-418
    • /
    • 2001
  • The measurement of residual stresses by the hole-drilling method has been commonly used to evaluate residual stresses in structural members. In this method, eccentricity can usually occur between the hole center and rosette gage center. In this study, the error due to the hole eccentricity is corrected using the neural network. The neural network has trained training examples of normalized eccentricity, eccentric direction and direction of maximum stress at eccentric case using backpropagation learning process. The trained neural network could corrected the error of measured residual stress in experiments with hole eccentricity. The proposed neural network is very useful for correction of the error due to hole eccentricity in hole-drilling method.

  • PDF

Compensation of the Error due to Hole Eccentricity of Hole-drilling Method in Uniaxile Residual Stress Field Using Neural Network (신경망 기법을 이용한 1축 잔류응력장에서 구멍뚫기법의 구멍편심 오차 보정)

  • Kim, Cheol;Yang, Won-Ho;Cho, Myoung-Rae
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.26 no.12
    • /
    • pp.2475-2482
    • /
    • 2002
  • The measurement of residual stresses by the hole-drilling method has been commonly used to evaluate residual stresses in structural members. In this method, eccentricity can usually occur between the hole center and rosette gage center. In this study, the error due to the hole eccentricity is compensated using the neural network. The neural network has trained training examples of normalized eccentricity, eccentric direction and direction of maximum stress at eccentric case using backpropagation learning process. The trained neural network could compensated the error of measured residual stress in experiments with hole eccentricity. The proposed neural network is very useful for compensation of the error due to hole eccentricity in hole-drilling method.