• Title/Summary/Keyword: Cylindrical

Search Result 4,348, Processing Time 0.031 seconds

The Optimum Design of Reinforced Concrete Cylindrical Shell Tanks (철근콘크리트 원통 SHELL TANK 에 관한 최적설계)

  • Choi, Yeal;Kang, Moon-Myung;Pulmano, Victor. A.
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 1992.10a
    • /
    • pp.61-66
    • /
    • 1992
  • The present paper deals with the optimum design of reinforced concrete cylindrical shell tanks in according to ACI 318-89 code. The purpose of this investigation is to find the optimum values of the steel ratio and the effective thickness of reinforced concrete cylindrical shell tanks. The analysts is carried out using a simple computer programming, SMAP(segmented matrix analysis package). The optimization is carried out using GINO programming. Optimum results for cylindrical shell tanks with uniform, stepwise and piecewise linealy varying thicknesses are presented.

  • PDF

Buckling Behavior of Stiffened Laminated Composite Cylindrical Panel (보강된 복합적층 원통형패널의 좌굴거동)

  • 이종선;원종진;홍석주;윤희중
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.12 no.5
    • /
    • pp.88-93
    • /
    • 2003
  • Buckling behavior of stiffened laminated composite cylindrical panel was studied using linear and nonlinear deformation theory. Various buckling load factors are obtained for stiffened laminated composite cylindrical panels with rectangular type longitudinal stiffeners and various longitudinal length to radius ratio, which made from Carbon/Epoxy USN150 prepreg and are simply-supported on four edges under uniaxial compression. Buckling behavior design analyses are carried out by the nonlinear search optimizer, ADS.

The Implementation and Experiments of Open-Loop Cylindrical Vibratory Gyroscope (개루프 제어의 실린더 진동형 자이로 구현 및 실험)

  • 공형직;김정엽;홍성경
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.10 no.8
    • /
    • pp.669-672
    • /
    • 2004
  • This paper considers the implementation and experiments of an open-loop Cylindrical Vibratory Gyroscope(CGV). An open-loop CGV composed of thin cylindrical vibrating element, electromagnetic drive and pick-off element with open-loop control was designed and fabricated. The experimental performance tests of the open-loop CGV were done using a temperature chambered rate table. Also, the limitations of open-loop CGV were analyzed and the solution for the limitations was proposed.

Critical Buckling Loads of Laminated Composites under Cylindrical Bending (원통형 굽힘을 받는 적층판의 임계좌굴 하중)

  • Lee, Soo-Yong
    • Journal of Aerospace System Engineering
    • /
    • v.1 no.4
    • /
    • pp.28-36
    • /
    • 2007
  • This paper presents critical buckling loads of laminated composites under cylindrical bending. In-plane displacements are assumed to vary exponentially through plate thickness. The accuracy of this theory is examined for symmetric/antisymmetric cross-ply, angle-ply and unsymmetric laminates under cylindrical bending. Analytical solutions are provided to investigate the effect of transverse shear deformation on critical buckling loads of the laminated plates, and the results are compared with those obtained from the first-order shear deformation plate theory and the classical laminated plate theory.

  • PDF

SURFACES WITH POINTWISE 1-TYPE GAUSS MAP

  • Kim, Dong-Soo
    • The Pure and Applied Mathematics
    • /
    • v.18 no.4
    • /
    • pp.369-377
    • /
    • 2011
  • In this article, we study generalized slant cylindrical surfaces (GSCS's) with pointwise 1-type Gauss map of the first and second kinds. Our main results state that GSCS's with pointwise 1-type Gauss map of the first kind coincide with surfaces of revolution with constant mean curvature; and the right cones are the only polynomial kind GSCS's with pointwise 1-type Gauss map of the second kind.

Effects of elastic foundation on the dynamic stability of cylindrical shells

  • Ng, T.Y.;Lam, K.Y.
    • Structural Engineering and Mechanics
    • /
    • v.8 no.2
    • /
    • pp.193-205
    • /
    • 1999
  • A formulation for the dynamic stability analysis of cylindrical shells resting on elastic foundations is presented. In this previously not studied problem, a normal-mode expansion of the partial differential equations of motion, which includes the effects of the foundation as well as a harmonic axial loading, yields a system of Mathieu-Hill equations the stability of which is analyzed using Bolotin's method. The present study examines the effects of the elastic foundation on the instability regions of the cylindrical shell for the transverse, longitudinal and circumferential modes.

User-Defined Hand Gestures for Small Cylindrical Displays (소형 원통형 디스플레이를 위한 사용자 정의 핸드 제스처)

  • Kim, Hyoyoung;Kim, Heesun;Lee, Dongeon;Park, Ji-hyung
    • The Journal of the Korea Contents Association
    • /
    • v.17 no.3
    • /
    • pp.74-87
    • /
    • 2017
  • This paper aims to elicit user-defined hand gestures for the small cylindrical displays with flexible displays which has not emerged as a product yet. For this, we first defined the size and functions of a small cylindrical display, and elicited the tasks for operating its functions. Henceforward we implemented the experiment environment which is similar to real cylindrical display usage environment by developing both of a virtual cylindrical display interface and a physical object for operating the virtual cylindrical display. And we showed the results of each task in the virtual cylindrical display to the participants so they could define the hand gestures which are suitable for each task in their opinion. We selected the representative gestures for each task by choosing the gestures of the largest group in each task, and we also calculated agreement scores for each task. Finally we observed mental model of the participants which was applied for eliciting the gestures, based on analyzing the gestures and interview results from the participants.

Using structural intensity approach to characterize vibro-acoustic behavior of the cylindrical shell structure

  • Wang, Yuran;Huang, Rong;Liu, Zishun
    • Coupled systems mechanics
    • /
    • v.7 no.3
    • /
    • pp.297-319
    • /
    • 2018
  • In this paper, the vibro-acoustic behaviors of vibrational cylindrical shells are investigated by using structural intensity approach. The reducing interior noise method for vibrating cylindrical shells is proposed by altering and redistributing the structural intensity through changing the damping property of the structure. The concept of proposed novel method is based on the properties of structural intensity distribution on cylindrical shells under different load and damping conditions, which can reflects power flow in the structures. In the study, the modal formulas of structural intensity are developed for the steady state vibration of cylindrical shell structures. The detailed formulas of structural intensity are derived by substituting modal quantities, in which the effect of main parameters such as weight coefficients and distribution functions on structure intensity are analyzed and discussed. Numerical simulations are first carried out based on the structural intensity analytical solutions of modal formulas. Through simulating the coupling vibration and acoustical radiation problems of cylindrical shell, the relationship between vibro-acoustic and structural intensity distribution is derived. We find that for cylindrical shell, by properly arranging damping conditions, the structural intensity can be efficiently changed and further the noise property can be improved. The proposed methodology has important implications and potential applications in the vibration and noise control of fuselage structure.

Low-Load/Low-Eccentricity Performance Improvement Designs for Hydro Power Application of Cylindrical Turbine Guide Bearings - Introduction of Pad Leading-Edge Tapers (수력 원통형 터빈 가이드 베어링의 저부하/저편심 성능향상 설계 - 패드 선단 테이퍼의 도입)

  • Lee, An Sung;Jang, Sun-Yong
    • Tribology and Lubricants
    • /
    • v.33 no.2
    • /
    • pp.65-70
    • /
    • 2017
  • In vertical hydro/hydraulic power turbine-generator applications, traditionally, cylindrical turbine guide bearings (TGBs) are widely used to provide turbine runner shafts with smooth rotation guides and supports. All existing cylindrical TGBs with simple plain pads have drawbacks such as having no pressure generation and film stiffness at the no-load condition and in addition, at the low-load/low-eccentricity condition, having very low film stiffness values and lacking design credibility in the stiffness values themselves. In this paper, in order to fundamentally improve the low-load/low-eccentricity performance of conventional cylindrical TGBs and thus enhance their design-application availability and usefulness, we propose to introduce a rotation-directional leading-edge taper to each partitioned pad, i.e., a pad leading-edge taper. We perform a design analysis of lubrication performance on $4-Pad{\times}4-Row$ cylindrical TGBs to verify an engineering/technical usefulness of the proposed pad leading-edge taper. Analysis results show that by introducing the leading-edge taper to each pad of the cylindrical TGB one can expect a constant high average direct stiffness with a high degree of design credibility, regardless of load value, even at the low-load/low-eccentricity condition and also control the average direct stiffness value by exploring the taper height as a design parameter. Therefore, we conclude that the proposed pad leading-edge tapers are greatly effective in more accurately predicting and controlling rotordynamic characteristics of vertical hydro-power turbine-generator rotor-bearing systems to which cylindrical TGBs are applied.