• 제목/요약/키워드: Stability check

검색결과 377건 처리시간 0.023초

초고층 건물의 시공 중 안정성 검토를 위한 시공단계해석 (Construction Sequence Analysis for Checking Stability in High-Rise Building under Construction)

  • 김재요
    • 한국전산구조공학회:학술대회논문집
    • /
    • 한국전산구조공학회 2008년도 정기 학술대회
    • /
    • pp.618-623
    • /
    • 2008
  • Due to recent trends of the atypical plan shapes and the zoning construction in high-rise buildings, the building stability under construction is arising as an important issue for design and construction plan. To ensure the stability under construction, the differential column shortening and the lateral movements with unbalanced distributions of self-weight of structure members and the load flows before completion of member connections and lateral load resisting system should be checked by construction sequence analysis. This paper presents the scheme of zone-based construction sequence analysis, to check the stability of high-rise building under construction. This scheme is applied to the construction sequence analysis for real high-rise building under construction.

  • PDF

강우시 철도성토사면의 열차운전규제기준에 관한 연구 (A Study on the rail-transport operation control for railway embankment under rainfall)

  • 김현기;박영곤;신민호;김수삼
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2001년도 추계학술대회 논문집
    • /
    • pp.514-519
    • /
    • 2001
  • There are a close relationship between natural disasters and train safety. So it is very important to guaranty train safety using reasonable rail-transport operation control against disasters. Therefore, based on the past record of rainfall at failure, rail-transport operation control for railway embankment under rainfall was set up. After slope check list at home and abroad had been analyzed, new slope check list was suggested and site investigations were carried out using this check list. In order to evaluate the stability of railway slopes under rainfall, explanatory variables and subordinate variables were selected for multi-variate analysis and critical rainfall was defined by statistical process. Rail-transport operation control including regional and geological properties was suggested by analyzing the critical rainfall and rail-transport operation control in other country, and this will be a good tool to control train speed under rainfall and to secure train safety.

  • PDF

Stability of Time Delay Systems Using Numerical Computation of Argument Principles

  • Suh, Young-Soo
    • International Journal of Control, Automation, and Systems
    • /
    • 제1권1호
    • /
    • pp.127-133
    • /
    • 2003
  • This paper proposes a new numerical method to check the stability of a general class of time delay systems. The proposed method checks whether there are characteristic roots whose real values are nonnegative through two steps. Firstly, rectangular bounds of characteristic roots whose real values are nonnegative are computed. Secondly, the existence of roots inside the bounds are checked using the numerical computation of argument principles. An adaptive discretization is proposed for the numerical computation of argument principles.

GENERALIZED MODULE LEFT (m, n)-DERIVATIONS

  • Lee, Sung Jin;Lee, Jung Rye
    • 한국수학교육학회지시리즈B:순수및응용수학
    • /
    • 제23권4호
    • /
    • pp.385-387
    • /
    • 2016
  • $Fo{\check{s}}ner$ [4] defined a generalized module left (m, n)-derivation and proved the Hyers-Ulam stability of generalized module left (m, n)-derivations. In this note, we prove that every generalized module left (m, n)-derivation is trival if the algebra is unital and $m{\neq}n$.

Load/Unload 하드디스크 드라이브 시스템에의 Fold Bifurcations의 교란 유한요소 해석 (Perturbed Finite Element Analysis of Fold Bifurcations in Load/unload Bard Disk Drive Systems)

  • 황평;콴폴리냐
    • 정보저장시스템학회:학술대회논문집
    • /
    • 정보저장시스템학회 2005년도 추계학술대회 논문집
    • /
    • pp.177-178
    • /
    • 2005
  • The load/unload behavior of the hard disk drive slider is studied in terms of the air bearing static characteristics. The numerical continuation methods are applied to calculate suspension force - equilibrium position curve. The critical preloads of the femto size slider are analyzed. The hi-stability conditions are depicted on the skew angle - preload diagram. The perturbation method is used to check the stability of the solution branches.

  • PDF

자세 제어 장치와 능동 후륜 조향을 이용한 최적 요 모멘트 분배 (Optimum Yaw Moment Distribution with Electronic Stability Control and Active Rear Steering)

  • 임성진
    • 제어로봇시스템학회논문지
    • /
    • 제20권12호
    • /
    • pp.1246-1251
    • /
    • 2014
  • This article presents an optimum yaw moment distribution scheme for a vehicle with electronic stability control (ESC) and active rear steering (ARS). After computing the control yaw moment in the yaw moment controller, it should be distributed into tire forces, generated by ESC and ARS. In this paper, yaw moment distribution is formulated as an optimization problem. New objective function is proposed to tune the relative magnitudes of the tire forces. Weighed pseudo-inverse control allocation (WPCA) is adopted to solve the problem. To check the effectiveness of the proposed scheme, simulation is performed on a vehicle simulation package, CarSim. From the simulation, the proposed optimum yaw moment distribution scheme is shown to effective for vehicle stability control.

지상환경하에서 복합재료의 물성저하를 고려한 한국형 틸팅열차 하이브리드 차체 구조물의 정적안정성 평가 (Evaluation of Static Stability of Hybrid Carbody Structures of Korean Tilting Train eXpress Including Degradation Effects of Composite Materials under Ground Environments)

  • 신광복;한성호
    • 대한기계학회논문집A
    • /
    • 제28권6호
    • /
    • pp.807-815
    • /
    • 2004
  • In order to evaluate the static stability of hybrid carbody structures of Korean Tilting Train eXpress(TTX) caused by degradation of composites under ground environments, T300/AD6005 graphite/epoxy composite specimens were exposed to accelerated environmental conditions including ultraviolet radiation, temperature and moisture fer 2000 hours. It was found that the stiffness and strength of composites after aging were lower than those of unexposed specimens, and decreased as the aging time increases. The values of the degraded properties were used in the static analysis to check the static stability of hybrid carbody structures caused by environmental degradation of composites. The results shown that the structural stability of hybrid carbody structures was affected by the degradation of composites after exposure to accelerated aging environments.

식품 소재로서 장미꽃잎 색소의 안정성 (Stability for Rose Petals Pigment as a Food Material)

  • 양미옥;조은자
    • 동아시아식생활학회지
    • /
    • 제16권4호
    • /
    • pp.468-473
    • /
    • 2006
  • This study was conducted to develop pigment of flowers as a food material and the red rose(Rosa hybrida L.) was used for this study. To check the possibility of using the rose pigment as a food additive we have extracted the pigment from rose and examined all the factors (pH, temperature, free sugars, organic acids, metal ions) for stability. The results obtained are as follows: In examining the stability of the pigment, the residue of the pigment noticeably decreased with the increase of the pH and the temperature, and among free sugars (fructose, glucose, sucrose) the addition of fructose made the residue the lowest. With the addition of organic acids the samples exhibited the hyperchromic effect throughout the period of the storage. The pigment residue decreased when the amount of the metal ions increased and especially the Cu$^{2+}$ ion was most destructive.

  • PDF

선형 스위칭 시스템의 관측기 기반 제어 (Observer-based Control for Switched Linear Systems)

  • 염동회;임기홍;최진영
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
    • /
    • pp.92-94
    • /
    • 2004
  • In the previous work, we proposed a new stability criterion for the stability of switched linear systems. By the proposed criterion, we could simply check the stability of switched linear systems because the criterion is applicable to each individual subsystem without need to consider the overall system. Using this criterion, we provided the methods that design a state feedback control when full states are available. In this paper, we apply the same criterion to the case when full states are not available. Unlike existing method such as dwelling time analysis, the proposed method is suitable to a fast switching process because there is no need to consider dwelling time. And we can easily achieve designing multi-controller, multi-estimator, and the supervisor by means of the proposed method.

  • PDF