• 제목/요약/키워드: limit of function

검색결과 1,142건 처리시간 0.036초

다양한 케이블 요소를 이용한 강사장교의 극한강도 평가 (Evaluation of Limit Strength for Steel Cable-Stayed Bridgesusing Various Cable Elements)

  • 송원근;이종우
    • 한국구조물진단유지관리공학회 논문집
    • /
    • 제10권5호
    • /
    • pp.115-121
    • /
    • 2006
  • 본 논문에서는 다양한 형태의 케이블 요소들의 거동이 강사장교의 극한강도에 미치는 영향을 검토하였다. 연화소성힌지 모델을 사용한 극한강도 평가 시 보-기둥 부재의 기하학적 비선형은 안정함수를 사용하여 고려하였고 재료적 비선형성을 반영하기 위하여 CRC 접선계수와 포물선 함수를 사용하였다. 케이블 부재는 새그의 영향이 고려되었다. 연구 결과 등가탄성계수가 반영된 등가트러스 요소를 사용한 경우 강사장교의 극한강도가 케이블 요소 또는 현수선 요소를 사용하여 평가한 극한강도 보다 안전측으로 평가되었다.

속도제한 지원장치에 대한 운전자 인식도 및 도로환경 분석 (A study on Korean drivers' acceptance and traffic sign conditions assessment for Speed Assistance Systems)

  • 이화수;조재호;임종현;이홍국;장경진;유송민
    • 자동차안전학회지
    • /
    • 제7권3호
    • /
    • pp.30-34
    • /
    • 2015
  • This study examined the Korean drivers' acceptance of SAS(Speed Assistance systems) and traffic sign conditions in Korea roads for SLIF(Speed Limit Information Function) that is a part of SAS. Exceeding the speed limit is a factor in the severity of many road accidents and SAS would help the driver to observe a speed limit by warning and/or effectively limiting the speed of the vehicle. SAS are in the initial phase in Korea, Korean drivers could not be familiar with automatical speed limiting during driving, SAS interface design would be considered to be more readily acceptable to the public. And advanced SAS have been introduced onto the market which are able to inform the driver of the current speed limit based on camera and/or digital maps based SLIF. These systems are based on external data using sensors, so environmental conditions are an important factor which could cause malfunction of SLIF functions.

노인의 연령, 체중, 신장과 안정성한계의 상관관계 (The Relationship between age, height, weight and Limit of Stability on the Elderly)

  • 신상철;김진상
    • The Journal of Korean Physical Therapy
    • /
    • 제12권2호
    • /
    • pp.153-163
    • /
    • 2000
  • This study was conducted to examine the relationship between limit of stability and age, height and weight. 83 healthy elderly(male 40, female 43) were measured the limit of stability and demographic characteristics. The results were as follows. 1. Left-right limit of stability was correlated with age in the elderly. 2. Left-right limit of stability was not correlated with the height, weight in the elderly. 3. Anterior-posterior limit of stability was correlated with age. height and weight in the elderly. So it is recommended that high risk groups - more aged people. of elderly should be offered the exercise program for increasing the limit of stability and well-designed studies of proper exercise program for musculoskeletal function and muscle power elevation should be performed.

  • PDF

치수 불확실성이 고려된 군용 통신 장비의 신뢰성 기반 최적설계 (The Reliability-based Design Optimization for the Military Communication Equipment considering the Dimension Uncertainty)

  • 박대웅
    • 한국소음진동공학회논문집
    • /
    • 제21권11호
    • /
    • pp.1051-1058
    • /
    • 2011
  • The military communication equipment is required the high reliability for operating adequate functions under severe conditions. This reliability is the essential element for the quality of the product, for the uncontrolled factors, such as the clearance, damage of the material, the reduction of stiffness, which are the designer is unable to handle. In this paper, the uncertainty for the dimension was supposed to the probability model for the military communication equipment, and the average of the objective function was minimized for reducing design uncertainty. The reliability-based design optimization which was implemented the limit state function was formulated into the mathematical model, so the reliable optimized structure was implemented than the base-line design.

설계 불확실성이 고려된 군용 통신 장비의 신뢰성 기반 최적설계 (The Reliability-Based Design Optimization for the Military Communication Equipment considering the Design Uncertainty)

  • 박대웅;문우용
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2011년도 추계학술대회 논문집
    • /
    • pp.504-509
    • /
    • 2011
  • The military communication equipment is required the high reliability for operating adequate functions under severe conditions. This reliability is the essential element for the quality of the product, for the uncontrolled factors, such as the clearance, damage of the material, the reduction of stiffness, which are the designer is unable to handle. In this paper, the uncertainty for the design was supposed to the probability model for the military communication equipment, and the average of the objective function was minimized for reducing design uncertainty. The reliability-based design optimization which was implemented the limit state function was formulated into the mathematical model, so the reliable optimized structure was implemented than the base-line design.

  • PDF

Error Rate for the Limiting Poisson-power Function Distribution

  • Joo-Hwan Kim
    • Communications for Statistical Applications and Methods
    • /
    • 제3권1호
    • /
    • pp.243-255
    • /
    • 1996
  • The number of neutron signals from a neutral particle beam(NPB) at the detector, without any errors, obeys Poisson distribution, Under two assumptions that NPB scattering distribution and aiming errors have a circular Gaussian distribution respectively, an exact probability distribution of signals becomes a Poisson-power function distribution. In this paper, we show that the error rate in simple hypothesis testing for the limiting Poisson-power function distribution is not zero. That is, the limit of ${\alpha}+{\beta}$ is zero when Poisson parameter$\kappa\rightarro\infty$, but this limit is not zero (i.e., $\rho\ell$>0)for the Poisson-power function distribution. We also give optimal decision algorithms for a specified error rate.

  • PDF

An efficient response surface method considering the nonlinear trend of the actual limit state

  • Zhao, Weitao;Qiu, Zhiping;Yang, Yi
    • Structural Engineering and Mechanics
    • /
    • 제47권1호
    • /
    • pp.45-58
    • /
    • 2013
  • In structural reliability analysis, the response surface method is a powerful method to evaluate the probability of failure. However, the location of experimental points used to form a response surface function must be selected in a judicious way. It is necessary for the highly nonlinear limit state functions to consider the design point and the nonlinear trend of the limit state, because both of them influence the probability of failure. In this paper, in order to approximate the actual limit state more accurately, experimental points are selected close to the design point and the actual limit state, and consider the nonlinear trend of the limit state. Linear, quadratic and cubic polynomials without mixed terms are utilized to approximate the actual limit state. The direct Monte Carlo simulation on the approximated limit state is carried out to determine the probability of failure. Four examples are given to demonstrate the efficiency and the accuracy of the proposed method for both numerical and implicit limit states.

Limit analysis of plates-a finite element formulation

  • Capsoni, Antonio;Corradi, Leone
    • Structural Engineering and Mechanics
    • /
    • 제8권4호
    • /
    • pp.325-341
    • /
    • 1999
  • A procedure for the computation of the load carrying capacity of perfectly plastic plates in bending is presented. The approach, based on the kinematic theorem of limit analysis, requires the evaluation of the minimum of a convex, but non-smooth, function under linear equality constraints. A systematic solution procedure is devised, which detects and eliminates the finite elements which are predicted as rigid in the collapse mechanism, thus reducing the problem to the search for the minimum of a smooth and essentially unconstrained function of nodal velocities. Both Kirchhoff and Mindlin plate models are considered. The effectiveness of the approach is illustrated by means of some examples.

상용 유한요소 프로그램에 기초한 댐 구조물의 신뢰성해석 (Commercial Finite Element Program-based Reliability Analysis of Dam Structures)

  • 허정원;이정학
    • 한국전산구조공학회:학술대회논문집
    • /
    • 한국전산구조공학회 2003년도 봄 학술발표회 논문집
    • /
    • pp.103-110
    • /
    • 2003
  • A hybrid structural reliability analysis method that integrates a commercial finite element program and a reliability analysis algorithm is proposed to estimate the safety of real structures in this paper. Since finite element method (FEM) is most commonly and widely used in the analysis and design practice of real structures, it appears to be necessary to use general FEM program in the structural reliability analysis. In this case, simple conventional reliability methods cannot be used because the limit state function can only be expressed in an algorithmic form. The response surface method(RSM)-based reliability algorithm with the first-order reliability method (FORM) found to be ideal in this respect and is used in this paper. The intention of use of RSM is to develop, albeit approximately, an explicit expression of the limit state function for real structures. The applicability of the proposed method to real structures is examined with help of the example in consideration of a concrete dam. Both the strength and serviceability limit states are considered in this example.

  • PDF

이차손실함수 하에서 최적 공정평균 및 규격하한 (Optimum Mean Value and Lower Limit under a Quadratic Loss Function)

  • 홍성훈;최성일;임훈;반재석
    • 품질경영학회지
    • /
    • 제28권4호
    • /
    • pp.194-203
    • /
    • 2000
  • This paper is concerned with an economic selection of both the process mean and the lower limit for a continuous production process with the quadratic loss function. It is assumed that the quality characteristic is normally distributed with a known variability. A profit model is developed which involves selling price, production cost, reprocessing cost and the cost which is incurred by imperfect quality. Methods of finding optimum values of the process mean and the lower limit are presented, and a numerical example is given.

  • PDF