• Title/Summary/Keyword: 응답

Search Result 13,863, Processing Time 0.036 seconds

Design Sensitivity Analysis of Frequency Response Using Krylov Subspace Based Model Reduction (Krylov 부공간 축소기법을 이용한 주파수응답의 설계민감도 해석)

  • Han, Jeong-Sam
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2009.04a
    • /
    • pp.131-134
    • /
    • 2009
  • Krylov 부공간 모델차수축소법은 초기 유한요소모델과 축소모델의 전달함수의 계수인 모멘트를 일치시키는 방법을 이용하는 축소기법으로 이미 대형 유한요소모델의 주파수응답 해석의 효율적인 계산에 많이 사용되고 있는 방법 중의 하나이다. 본 논문에서는 Krylov 부공간 축소기법을 이용한 관심 주파수영역에 대한 주파수응답 해석 및 이를 통하여 계산된 주파수응답의 여러 가지 설계변수에 대한 설계민감도 해석방법을 제안하였다. 일반적으로 구조물의 주파수응답을 고려한 최적설계를 위해서는 설계변수에 대한 관심 주파수영역에서의 주파수응답 및 그의 민감도 정보가 요구되므로, 고려하는 유한요소모델이 대형일 경우에 관심 주파수영역에서의 반복적인 해석으로 인한 계산비용의 문제가 대두된다. 본 논문에서는 축소모델을 이용하여 주파수응답과 주파수응답의 설계민감도 해석을 수행하여 계산의 효율성을 극대화하였다. 민감도 계산에는 시간측면과 구현의 용이성 측면에서 장점이 있는 준해석적 방법을 이용하였다. 수치 예제를 통하여 축소기법을 이용한 주파수응답의 설계민감도 해석 결과를 유한차분법에 근거한 민감도 결과와 비교하였다. 본 논문에서 제안된 방법을 이용하는 경우, 주파수응답을 고려한 최적설계를 계산비용 측면에서 매우 효율적으로 수행할 수 있을 것이다.

  • PDF

Evaluations of Velocity Response Spectrum of Seismic Base and Response Displacement for the Seismic Design of Underground Structures (지중구조물 내진설계를 위한 기반면의 속도 응답스펙트럼 및 응답변위 산정기법에 대한 연구)

  • 윤종구;김동수;유제남
    • Journal of the Korean Geotechnical Society
    • /
    • v.19 no.4
    • /
    • pp.211-221
    • /
    • 2003
  • The response displacement method is the most frequently used method for seismic design of underground structures. This method is pseudo-static method, and the evaluations of velocity response spectrum of seismic base and response displacement of surrounding soil are the most important steps. In this study, the evaluation of velocity response spectrum of seismic base according to the Korean seismic design guide and the simple method of calculating the response displacement were studied. It was found that velocity response spectrum of seismic base can be estimated by directly integrating the ground-surface acceleration response spectrum of soil type S$_A$, and the evaluation of the response displacement using double cosine method assuming two layers of soil profile shows the advantages in the seismic design.

Transfer Learning-based Multi-Modal Fusion Answer Selection Model for Video Question Answering System (비디오 질의 응답 시스템을 위한 전이 학습 기반의 멀티 모달 퓨전 정답 선택 모델)

  • Park, Gyu-Min;Park, Seung-Bae
    • Annual Conference on Human and Language Technology
    • /
    • 2021.10a
    • /
    • pp.548-553
    • /
    • 2021
  • 비디오 질의 응답은 입력으로 주어진 비디오와 질문에 적절할 정답을 제공하기 위해 텍스트, 이미지 등 다양한 정보처리가 요구되는 대표적인 multi-modal 문제이다. 질의 응답 시스템은 질의 응답의 성능을 높이기 위해 다수의 서로 다른 응답 모듈을 사용하기도 하며 생성된 정답 후보군 중 가장 적절할 정답을 선택하는 정답 선택 모듈이 필요하다. 정답 선택 모듈은 응답 모듈의 서로 다른 관점을 고려하여 응답 선택을 선택할 필요성이 있다. 하지만 응답 모듈이 black-box 모델인 경우 정답 선택 모듈은 응답 모듈의 parameter와 예측 분포를 통해 지식을 전달 받기 어렵다. 그리고 학습 데이터셋은 응답 모듈이 학습에 사용했기 때문에 과적합 문제로 각 모듈의 관점을 학습하기엔 어려우며 학습 데이터셋 이외 비교적 적은 데이터셋으로 학습해야 하는 문제점이 있다. 본 논문에서는 정답 선택 성능을 높이기 위해 전이 학습 기반의 멀티모달 퓨전 정답 선택 모델을 제안한다. DramaQA 데이터셋을 통해 성능을 측정하여 제안된 모델의 우수성을 실험적으로 증명하였다.

  • PDF

Forming Weighting Adjustment Cells for Unit-Nonresponse in Sample Surveys (표본조사에서 무응답 가중치 조정층 구성방법에 따른 효과)

  • Kim, Young-Won;Nam, Si-Ju
    • Communications for Statistical Applications and Methods
    • /
    • v.16 no.1
    • /
    • pp.103-113
    • /
    • 2009
  • Weighting is a common form of unit nonresponse adjustment in sample surveys where entire questionnaires are missing due to noncontact or refusal to participate. A common approach computes the response weight as the inverse of the response rate within adjustment cells based on covariate information. In this paper, we consider the efficiency and robustness of nonresponse weight adjustment bated on the response propensity and predictive mean. In the simulation study based on 2000 Fishry Census in Korea, the root mean squared errors for assessing the various ways of forming nonresponse adjustment cell s are investigated. The simulation result suggest that the most important feature of variables for inclusion in weighting adjustment is that they are predictive of survey outcomes. Though useful, prediction of the propensity to response is a secondary. Also the result suggest that adjustment cells based on joint classification by the response propensity and predictor of the outcomes is productive.

Nonlinear Response Analysis of Multi-Degree-of-Freedom Building Structures Using Response Spectrum Method (응답스펙트럼법에 의한 고층 건축물의 탄소성 지진응답해석법)

  • Jun, Dae-Han
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.1 no.4
    • /
    • pp.1-9
    • /
    • 1997
  • This paper examined various aspects of a linear and a nonlinear response spectrum method in seismic response analysis of multi-story building structures. The response spectrum method that has been widely used in the analysis of linear structures was proposed different mode superposition method by several ivestigators, and the differences between combinations with an elastic modal analysis reviwed closely. It seems, however, that this method is not used to nonlinear seismic analysis. It is the purpose of this paper to propose an alternative method by means of which a nonlinear MDOF structure with long period may be analysed by an extention of response spectrum method. For nonlinear seismic analysis of high-rise building structures using technique proposed in this study, it is intended to serve primarily as a tool in preliminary designs instead of time history analysis.

  • PDF

Analysis of Runoff Characteristics Using Multiple Impulse Response Functions (복수의 충격응답함수를 이용한 유역의 유출특성 분석)

  • Yoo, Chul-Sang;Kim, Ha-Young;Park, Joo-Young
    • Journal of Korea Water Resources Association
    • /
    • v.43 no.6
    • /
    • pp.571-581
    • /
    • 2010
  • This study analyzed rainfall-runoff characteristics by deriving multiple impulse responses. The concept of competing impulse responses was used for deriving multiple impulse responses. Based on this concept, each response function derived competes to be selected for simulating the runoff measured. This concept of competing linear impulse responses was applied to four basins, Jeongseon, Yeongwol, Youngchoon and Chungju Dam. One to three impulse responses have been derived and compared each other considering basin characteristics. First, in case of deriving one linear impulse response, the peak flow of the impulse response was found to be increased according to their study basins area. In case of deriving two linear impulse response, the peak flow of the first impulse response and the duration of the second impulse response were increased according to their basin size. The case of deriving three impulse response showed similar characteristics of deriving two impulse responses. However, the peak flow of third impulse response was very small and lasted quite long time. Summarizing these results considering the basin characteristics, the first impulse response seems to be related with the surface runoff, the second impulse with the surface runoff and interflow, and the third impulse response with the interflow and base flow.

유한패턴매칭을 이용한 자연어 질의응답 시스템

  • 이승우;이근배
    • Communications of the Korean Institute of Information Scientists and Engineers
    • /
    • v.22 no.4
    • /
    • pp.21-27
    • /
    • 2004
  • 질의응답(QA)은 주어진 질의에 대해, 적합한 문서가 아니라 정답 그 자체를 찾아주는 것이 목표이며, 진정한 의미에서의 정보검색(IR)에 한걸음 더 나아가려는 노력이다. 예를 들어, "타지마할은 어디에 있나\ulcorner"라는 질의에 대해 "인도의 아그라"라는 정확한 응답을 제시하는 것이 질의응답 시스템이 하고자 하는 바이다.의응답 시스템이 하고자 하는 바이다.

농가경제조사의 무응답 대체군 형성 방안

  • 이기재;김규성;김진
    • Proceedings of the Korean Statistical Society Conference
    • /
    • 2004.11a
    • /
    • pp.49-54
    • /
    • 2004
  • 본 연구에서는 표본 농가의 교체나 무응답으로 인한 데이터의 손실을 최소화하기 위하여 핫덱방법을 적용할 때 필요한 무응답 대체군 형성 방안을 제안하였다. 농가경제조사의 무응답 현황과 특성을 살펴보고, 대체군 형성 방안들을 비교할 수 있는 측도를 제안하였다. 제안된 비교 측도를 이용해서 대체군 형성 방안들을 비교하였다.

  • PDF

Comparison of Answering Mechanisms in Contingent Valuation Method (조건부가치측정의 응답메커니즘 비교)

  • Park, Joo Heon
    • Environmental and Resource Economics Review
    • /
    • v.17 no.2
    • /
    • pp.327-347
    • /
    • 2008
  • This study proposes a new answering mechanism of deciding whether to purchase or not under uncertainty-real risk answering mechanism (R-RAM) for real transaction and hypothetical risk answering mechanism (H-RAM). It IS also. shown that the traditional answering mechanism (TAM) assumed in most of existing contingent valuation methods should be applied in a real transaction without uncertainty. While the willingness to pay (WTP) being simply compared with the bidding price m TAM, the mean of WTP should be greater than the bidding pnce at least by the risk premium for a purchase decision m R-RAM and H-RAM. Only difference between R-RAM and H-RAM is risk premium. The H-RAM takes a smaller risk premium than the R-RAM. This study proposes the contingent valuation method (CVM) with H-RAM could be an alternative to reducing the under-or over-estimation of WTP by comparing the WTP estimates obtained from three different CVMs with TAM, R-RAM and H-RAM.

  • PDF

Fast Graphic Visualization of Frequency Response for Audio Equalizer (오디오 이퀄라이저를 위한 주파수 응답의 고속 그래픽 표현 방법)

  • Kim, Ki-Jun;Park, Hochong
    • Journal of Broadcast Engineering
    • /
    • v.20 no.4
    • /
    • pp.632-640
    • /
    • 2015
  • This paper proposes a new method for fast graphic visualization of accurate frequency response of audio equalizer (EQ). When a logarithmic frequency scale is used, a frequency response in high resolution is required for accurate low-band frequency response. However, the high-resolution frequency response requires a huge amount of computational load, which makes the real-time graphic visualization of frequency response impossible. In order to solve the problem of computational load, the proposed method utilizes a low-resolution virtual frequency response in the mid band. It first computes the virtual frequency response of each filter of EQ in the mid band, and then moves it to the target band so that the result corresponds to the desired filter response. Then, it determines the final frequency response of EQ by combining all filter responses. The experiments confirm that the proposed method provides the frequency response of EQ which has an equivalent shape to that computed in high frequency resolution with huge computational load.