• 제목/요약/키워드: a priori

검색결과 764건 처리시간 0.028초

한반도 지진목록자료의 불완정성을 고려한 지진재해도 분석 (Seismic Hazard Analysis Considering the Incompleteness in the Korean Earthquake Catalog)

  • 연관희
    • 한국지진공학회:학술대회논문집
    • /
    • 한국지진공학회 1998년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Spring 1998
    • /
    • pp.413-420
    • /
    • 1998
  • In this paper, two methods, Stepp's and EQHAZARD, are introduced and applied to a recent earthquake catalog for the entire Korean Peninsula that can estimate the seismicity by incorporating the incompleteness of the earthquake catalog. EQHAZARD method, different from Stepp's method in that it used priori information besides the assumption of stationary Poisson process of the earthquakes, produces the higher seismicity rate for the smaller earthquakes. EQHAZARD method are also used to estimated the incompleteness of the recent earthquake catalog for the southern part of the Korean Peninsula in terms of the Probability of Activity for the specified earthquke magnitude classes and time periods. It is believed that the Probability of Activity thus obtained can be used as a strong priori information in estimating the seismicity for a seismic source within the region where there are not enough earthquakes detected. Finally, it is demonstrated that the arbitrary selection of the methods. of incompleteness analysis brings quite different seismic hazard results, which suggests the need to employ a rigid quantitative method for incompleteness analysis in estimating the seismicity parameters in order to reduce the uncertainty in the Seismic Hazard Results with the EQHAZARD method being one of the competent practical alternatives.

  • PDF

Multicriteria-Based Computer-Aided Pronunciation Quality Evaluation of Sentences

  • Yoma, Nestor Becerra;Berrios, Leopoldo Benavides;Sepulveda, Jorge Wuth;Torres, Hiram Vivanco
    • ETRI Journal
    • /
    • 제35권1호
    • /
    • pp.89-99
    • /
    • 2013
  • The problem of the sentence-based pronunciation evaluation task is defined in the context of subjective criteria. Three subjective criteria (that is, the minimum subjective word score, the mean subjective word score, and first impression) are proposed and modeled with the combination of word-based assessment. Then, the subjective criteria are approximated with objective sentence pronunciation scores obtained with the combination of word-based metrics. No a priori studies of common mistakes are required, and class-based language models are used to incorporate incorrect and correct pronunciations. Incorrect pronunciations are automatically incorporated by making use of a competitive lexicon and the phonetic rules of students' mother and target languages. This procedure is applicable to any second language learning context, and subjective-objective sentence score correlations greater than or equal to 0.5 can be achieved when the proposed sentence-based pronunciation criteria are approximated with combinations of word-based scores. Finally, the subjective-objective sentence score correlations reported here are very comparable with those published elsewhere resulting from methods that require a priori studies of pronunciation errors.

Advanced Design Environmental With Adaptive And Knowledge-Based Finite Elements

  • Haghighi, Kamyar;Jang, Eun
    • 한국농업기계학회:학술대회논문집
    • /
    • 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
    • /
    • pp.1222-1229
    • /
    • 1993
  • An advanced design environment , which is based on adaptive and knowledge -based finite elements (INTELMESH), has been developed. Unlike other approaches, INTEMMESH incorporates the information about the object geometry as well as the boundary and loading conditions to generate an ${\alpha}$-priori finite element mesh which is more refined around the critical regions of the problem domain. INTEMMESH is designed for planar domains and axisymmetric 3-D structures of elasticity and heat transfer subjected to mechanical and thermal loading . It intelligently identifies the critical regions/points in the problem domain and utilize the new concepts of substructuring and wave propagation to choose the proper mesh size for them. INTEMMESH generates well-shaped triangular elements by applying trangulartion and Laplacian smoothing procedures. The adaptive analysis involves the intial finite elements analyze and an efficient ${\alpha}$-posteriori error analysis involves the initial finite element anal sis and an efficient ${\alpha}$-posteriori error analysis and estimation . Once a problem is defined , the system automatically builds a finite element model and analyzes the problem though automatic iterative process until the error reaches a desired level. It has been shown that the proposed approach which initiates the process with an ${\alpha}$-priori, and near optimum mesh of the object , converges to the desired accuracy in less time and at less cost. Such an advanced design/analysis environment will provide the capability for rapid product development and reducing the design cycle time and cost.

  • PDF

유전자 알고리즘을 이용한 영상개선 필터 시스템 구현 (Implementation of Image Enhancement Filter System Using Genetic Algorithm)

  • 구지훈;동성수;이종호
    • 대한전기학회논문지:시스템및제어부문D
    • /
    • 제51권8호
    • /
    • pp.360-367
    • /
    • 2002
  • In this paper, genetic algorithm based adaptive image enhancement filtering scheme is proposed and Implemented on FPGA board. Conventional filtering methods require a priori noise information for image enhancement. In general, if a priori information of noise is not available, heuristic intuition or time consuming recursive calculations are required for image enhancement. Contrary to the conventional filtering methods, the proposed filter system can find optimal combination of filters as well as their sequent order and parameter values adaptively to unknown noise types using structured genetic algorithms. The proposed image enhancement filter system is mainly composed of two blocks. The first block consists of genetic algorithm part and fitness evaluation part. And the second block consists of four types of filters. The first block (genetic algorithms and fitness evaluation blocks) is implemented on host computer using C code, and the second block is implemented on re-configurabe FPGA board. For gray scale control, smoothing and deblurring, four types of filters(median filter, histogram equalization filter, local enhancement filter, and 2D FIR filter) are implemented on FPGA. For evaluation, three types of noises are used and experimental results show that the Proposed scheme can generate optimal set of filters adaptively without a pioi noise information.

근적외 스펙트럼을 이용한 정량분석용 최적 주성분회귀모델을 얻기 위한 알고리듬 (Algorithm for Finding the Best Principal Component Regression Models for Quantitative Analysis using NIR Spectra)

  • 조정환
    • Journal of Pharmaceutical Investigation
    • /
    • 제37권6호
    • /
    • pp.377-395
    • /
    • 2007
  • Near infrared(NIR) spectral data have been used for the noninvasive analysis of various biological samples. Nonetheless, absorption bands of NIR region are overlapped extensively. It is very difficult to select the proper wavelengths of spectral data, which give the best PCR(principal component regression) models for the analysis of constituents of biological samples. The NIR data were used after polynomial smoothing and differentiation of 1st order, using Savitzky-Golay filters. To find the best PCR models, all-possible combinations of available principal components from the given NIR spectral data were derived by in-house programs written in MATLAB codes. All of the extensively generated PCR models were compared in terms of SEC(standard error of calibration), $R^2$, SEP(standard error of prediction) and SECP(standard error of calibration and prediction) to find the best combination of principal components of the initial PCR models. The initial PCR models were found by SEC or Malinowski's indicator function and a priori selection of spectral points were examined in terms of correlation coefficients between NIR data at each wavelength and corresponding concentrations. For the test of the developed program, aqueous solutions of BSA(bovine serum albumin) and glucose were prepared and analyzed. As a result, the best PCR models were found using a priori selection of spectral points and the final model selection by SEP or SECP.

UNIFORM DECAY OF SOLUTIONS FOR VISCOELASTIC PROBLEMS

  • Bae, Jeong-Ja
    • East Asian mathematical journal
    • /
    • 제19권2호
    • /
    • pp.189-205
    • /
    • 2003
  • In this paper we prove the existence of solution and uniform decay rates of the energy to viscoelastic problems with nonlinear boundary damping term. To obtain the existence of solutions, we use Faedo-Galerkin's approximation, and also to show the uniform stabilization we use the perturbed energy method.

  • PDF

Design Science in e-business Research

  • Park, Jin-Soo
    • 한국전자거래학회:학술대회논문집
    • /
    • 한국전자거래학회 2004년도 e-Biz World Conference
    • /
    • pp.15-20
    • /
    • 2004
  • Positivism ▣Quantitative research ▣Descriptive, predictive, explanatory ▣Quest for university laws ▣Concerned with the empirical testability of theories (·Causal models (if it's not about cause-and-effect, it's not Science)) ▣Assumptions:(·Existence of a priori fixed relationship within phenomena ·Regular patterns of causation ·Independent from human mind(objective, factual)(omitted)

  • PDF

Fin de siècle 시기 오토 바그너의 집합주택 작품에 구현된 근대주거의 선험적 특질 (Priori Characteristics of Modern Housing Implemented in the Works of Otto Wagner at the Fin de siècle)

  • 전남일
    • 건축역사연구
    • /
    • 제26권1호
    • /
    • pp.45-59
    • /
    • 2017
  • The purpose of the present study is to figure out what the issues faced by architecture were at the time immediately before the transition to modern era centering of the works of Otto Wagner who acted in Vienna, Austria at the Fin de $si{\grave{e}}cle$. Therefore, the following points were examined in the present study; first, how were new spaces necessary to accommodate modern lives organized and how were the plans changed; second, how did the external expressions of architecture pursued by Otto Wagner appeared between arts and technologies, between historicism and modernity, and between decorations and functions. Through the study, it could be seen that Wagner began from historicism and traditionalism and tried to compromise them with modernity. Many modern characteristics appeared a priori in Wagner's works from the construction of 'Linke Wien Zeile housing block' in 1898, his works completely broke from the typical historicism styles to open the period of inventive 'Secession styles.' At that time, Wagner concentrated on so called 'flat decorations.' Thereafter, his residential architecture completed to modern styles with 'Neustiftgasse housing block' as the peak. The characteristics of modern housing as above became a cornerstone of the modern functionalism later.

IPMSM의 센서리스 운전을 위한 확장 칼만 필터 설계 (Extended Kalman Filter Design for Sensorless Control of IPMSM Drive)

  • 전용호;조민호
    • 한국전자통신학회논문지
    • /
    • 제8권11호
    • /
    • pp.1681-1690
    • /
    • 2013
  • 본 논문은 IPMSM(Interior Permanent Magnet Synchronous Motor)의 센서리스 운전을 위해 확장 칼만 필터를 기반으로 하는 속도와 위치 추정기의 설계방법을 제안한다. 제안된 방법은 상태 추정의 정밀도를 향상시키기 위해서 시스템 모델의 상태추정구간을 더욱 세분화하여 나누고, 세분화한 각 구간을 테일러급수 전개하여 일차항만 사용하여 추정하였다. 제안된 상태 추정기는 2차 확장칼만필터에 비해 사전추정의 연산의 양을 크게 하지 않고, 상태추정의 정밀도가 증가함을 시뮬레이션을 통해 보일 수 있었다.

실시간 동적 차분 위성항법을 위한 위치영역 Hatch 필터의 성능 해석 (Analyzing Position-Domain Hatch Filter for Real-Time Kinematic Differential GNSS)

  • 이형근;지규인
    • 한국항공우주학회지
    • /
    • 제34권2호
    • /
    • pp.48-55
    • /
    • 2006
  • 본 논문에서는 실시간 동적 차분 위성항법과 관련하여 근래에 제안된 위치영역 Hatch 필터의 오차 특성을 해석하였다. 위치영역 Hatch 필터에 의하여 생성되는 잉여값 순열 (residual sequence)이 고장검출에 유용한 백색잡음 (white noise) 특성을 가짐을 보였으며, 위치영역 Hatch 필터는 기존에 알려진 위치영역 Kalman 형 필터에 비하여 전 상태 추정치 (a priori state estimate) 의 정확도 면에서 오히려 더 우수함을 해석적으로 보였다. 이와 같은 특성에 의하면 차분 위성항법의 다양한 응용분야에서 위치영역 Hatch 필터가 고장검출 및 정밀측위에 효율적으로 사용될 수 있음을 알 수 있다.