• 제목/요약/키워드: Robustness

검색결과 4,365건 처리시간 0.028초

Parametric Inverse Scattering for Lossless Dispersive Media with Enhanced Robustness

  • Park, Hyoung-Jin;Lee, Sang-Seol
    • Journal of electromagnetic engineering and science
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    • 제3권1호
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    • pp.57-61
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    • 2003
  • The effects of high frequency noises on a perturbational inversion technique for a stratified dispersive medium are investigated in this paper. It is shown that the perturbational solution becomes unstable under high frequency noises. The physical origin of this instability is described. In order to enhance the robustness of the perturbational inverse scattering solution, a parametric inversion technique is introduced. The examples for the 2-pole and the 3-pole reflection coefficients are compared and contrasted, and improvement of the robustness of the solutions is shown.

Minimizing Weighted Mean of Inefficiency for Robust Designs

  • Seo, Han-Son
    • Communications for Statistical Applications and Methods
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    • 제15권1호
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    • pp.95-104
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    • 2008
  • This paper addresses issues of robustness in Bayesian optimal design. We may have difficulty applying Bayesian optimal design principles because of the uncertainty of prior distribution. When there are several plausible prior distributions and the efficiency of a design depends on the unknown prior distribution, robustness with respect to misspecification of prior distribution is required. We suggest a new optimal design criterion which has relatively high efficiencies across the class of plausible prior distributions. The criterion is applied to the problem of estimating the turning point of a quadratic regression, and both analytic and numerical results are shown to demonstrate its robustness.

다층퍼셉트론의 잡음 강건성 (On the Noise Robustness of Multilayer Perceptrons)

  • 오상훈
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2003년도 추계종합학술대회 논문집
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    • pp.213-217
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    • 2003
  • 이 논문에서는 MLP(Multilayer Perceptron)가 지닌 잡음 강건성에 대한 통계학적 분석을 하였다. 또한, MLP의 잡음 강건성을 향상시키기 위한 선형적 전처리 단계로써, ICA(independent component analysis)와 PCA(principle component analysis)를 고려하여, 이들이 지닌 잡음처리 효과를 분석한후, MLP와 접목시 나타나는 잡음 강건성의 향상 여부를 필기체 숫자 인식의 시뮬레이션으로 확인하였다.

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Robust Bayes and Empirical Bayes Analysis in Finite Population Sampling with Auxiliary Information

  • Kim, Dal-Ho
    • Journal of the Korean Statistical Society
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    • 제27권3호
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    • pp.331-348
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    • 1998
  • In this paper, we have proposed some robust Bayes estimators using ML-II priors as well as certain empirical Bayes estimators in estimating the finite population mean in the presence of auxiliary information. These estimators are compared with the classical ratio estimator and a subjective Bayes estimator utilizing the auxiliary information in terms of "posterior robustness" and "procedure robustness" Also, we have addressed the issue of choice of sampling design from a robust Bayesian viewpoint.

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Robustness and resilience of a passive control solution assembling buffer and cladding panels

  • Balzari, Ugo;Balzari, Andrea
    • Smart Structures and Systems
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    • 제20권5호
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    • pp.637-640
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    • 2017
  • The adoption of cladding panels as dissipation device is a sort of passive control "ante litteram" for residential and commercial buildings. This paper gives details on the current technology outlining the difference between buffer panels and cladding panels. The discussion of robustness and resilience of the resulting system is afforded. It is shown that the strength of such solution, originally related to economy and light weight, is mainly associated with the respect of the main robustness requisites, as well as the short time it requires for removal and replacement (resilience).

악성코드 변종 분석을 위한 AI 모델의 Robust 수준 측정 및 개선 연구 (A Study on Robustness Evaluation and Improvement of AI Model for Malware Variation Analysis)

  • 이은규;정시온;이현우;이태진
    • 정보보호학회논문지
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    • 제32권5호
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    • pp.997-1008
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    • 2022
  • 오늘날 AI(Artificial Intelligence) 기술은 악성코드 분야를 비롯하여 다양한 분야에서 광범위하게 연구되고 있다. 중요한 의사결정 및 자원을 보호하는 역할에 AI 시스템을 도입하기 위해서는 신뢰할 수 있는 AI 모델이어야 한다. 학습 데이터셋에 의존적인 AI 모델은 새로운 공격에 대해서도 견고한지 확인이 필요하다. 공격자는 악성코드를 새로 생성하기보단, 기존에 탐지되었던 악성코드의 변종을 대량 생산하여 공격에 성공하는 악성코드를 탐색다. AI 모델의 Misclassification을 유도하는 Adversarial attack과 같이 대부분의 공격은 기존 공격에 약간에 변형을 가해 만든 공격들이다. 이러한 변종에도 대응 가능한 Robust한 모델이 필요하며, AI 평가지표로 많이 사용되는 Accuracy, Recall 등으로는 모델의 Robustness 수준을 측정할 수 없다. 본 논문에서는 Adversarial attack 중 하나인 C&W attack을 기반으로 Adversarial sample을 생성하여 Robustness 수준을 측정하고 Adversarial training 을 통해 Robustness 수준을 개선하는 방법을 실험한다. 본 연구의 악성코드 데이터셋 기반 실험을 통해 악성코드 분야에서 해당 제안 방법의 한계 및 가능성을 확인하였다.

AC servo motor 제어시 rise time 과 강인성 개선 (Improvement in rise time and robustness of AC servomotor)

  • 정광조;임선종
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.446-450
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    • 1991
  • PID controller is popular but have defect inversing following reference input and noise elimination. Therefor, this paper focus on reducing rise time and robustness against noise. The result that is simulated with feedforward method and sliding mode show that rise time decrease and robustness increase.

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Robust Bayes and Empirical Bayes Analysis in Finite Population Sampling

  • Dal Ho Kim
    • Communications for Statistical Applications and Methods
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    • 제2권2호
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    • pp.63-73
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    • 1995
  • We consider some robust Bayes estimators using ML-II priors as well as certain empirical Bayes estimators in estimating the finite population mean. The proposed estimators are compared with the sample mean and subjective Bayes estimators in terms of "posterior robustness" and "procedure robustness".re robustness".uot;.

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Structural robustness of RC frame buildings under threat-independent damage scenarios

  • Ventura, Antonio;De Biagi, Valerio;Chiaia, Bernardino
    • Structural Engineering and Mechanics
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    • 제65권6호
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    • pp.689-698
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    • 2018
  • This study focuses on a novel procedure for the robustness assessment of reinforced concrete (RC) framed structures under threat-independent damage scenarios. The procedure is derived from coupled dynamic and non-linear static analyses. Two robustness indicators are defined and the method is applied to two RC frame buildings. The first building was designed for gravity load and earthquake resistance in accordance with Eurocode 8. The second was designed according to the tie force (TF) method, one of the design quantitative procedures for enhancing resistance to progressive collapse. In addition, in order to demonstrate the suitability and applicability of the TF method, the structural robustness and resistance to progressive collapse of the two designs is compared.

Robustness of 2nd-order Iterative Learning Control for a Class of Discrete-Time Dynamic Systems

  • 김용태
    • 한국지능시스템학회논문지
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    • 제14권3호
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    • pp.363-368
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    • 2004
  • In this paper, the robustness property of 2nd-order iterative learning control(ILC) method for a class of linear and nonlinear discrete-time dynamic systems is studied. 2nd-order ILC method has the PD-type learning algorithm based on both time-domain performance and iteration-domain performance. It is proved that the 2nd-order ILC method has robustness in the presence of state disturbances, measurement noise and initial state error. In the absence of state disturbances, measurement noise and initialization error, the convergence of the 2nd-order ILC algorithm is guaranteed. A numerical example is given to show the robustness and convergence property according to the learning parameters.