• 제목/요약/키워드: Recursive model function

검색결과 68건 처리시간 0.023초

첨두공진점을 갖는 모델 근사화를 위한 전달함수 합성법 (A Transfer Function Synthesis for Model Approximation with Resonance Peak Value)

  • 김종근;김주식;김흥규
    • 조명전기설비학회논문지
    • /
    • 제22권1호
    • /
    • pp.118-123
    • /
    • 2008
  • 본 논문은 주파수영역에서 첨두공진점을 갖는 고차모델을 저차모델로 근사화하기 위한 주파수 전달함수 합성법을 제안한다. 제안된 근사화 방법은 근사화된 모델의 분모 다항식에 가중된 오차함수의 최소화에 근거하며, 근사화된 모델의 주파수 전달함수에 대한 계수벡터를 추정하기 위해 RLS 기법을 이용한다. 제안된 방법은 저주파수와 첨두공진점에서 우수한 정합특성을 나타내며, 예제에 의해 제안된 방식의 유용성을 검증한다.

증분형 K-means 클러스터링 기반 방사형 기저함수 신경회로망 모델 설계 (Design of Incremental K-means Clustering-based Radial Basis Function Neural Networks Model)

  • 박상범;이승철;오성권
    • 전기학회논문지
    • /
    • 제66권5호
    • /
    • pp.833-842
    • /
    • 2017
  • In this study, the design methodology of radial basis function neural networks based on incremental K-means clustering is introduced for learning and processing the big data. If there is a lot of dataset to be trained, general clustering may not learn dataset due to the lack of memory capacity. However, the on-line processing of big data could be effectively realized through the parameters operation of recursive least square estimation as well as the sequential operation of incremental clustering algorithm. Radial basis function neural networks consist of condition part, conclusion part and aggregation part. In the condition part, incremental K-means clustering algorithms is used tweights of the conclusion part are given as linear function and parameters are calculated using recursive least squareo get the center points of data and find the fitness using gaussian function as the activation function. Connection s estimation. In the aggregation part, a final output is obtained by center of gravity method. Using machine learning data, performance index are shown and compared with other models. Also, the performance of the incremental K-means clustering based-RBFNNs is carried out by using PSO. This study demonstrates that the proposed model shows the superiority of algorithmic design from the viewpoint of on-line processing for big data.

Prediction Models of P-Glycoprotein Substrates Using Simple 2D and 3D Descriptors by a Recursive Partitioning Approach

  • Joung, Jong-Young;Kim, Hyoung-Joon;Kim, Hwan-Mook;Ahn, Soon-Kil;Nam, Ky-Youb;No, Kyoung-Tai
    • Bulletin of the Korean Chemical Society
    • /
    • 제33권4호
    • /
    • pp.1123-1127
    • /
    • 2012
  • P-gp (P-glycoprotein) is a member of the ATP binding cassette (ABC) family of transporters. It transports many kinds of anticancer drugs out of the cell. It plays a major role as a cause of multidrug resistance (MDR). MDR function may be a cause of the failure of chemotherapy in cancer and influence pharmacokinetic properties of many drugs. Hence classification of candidate drugs as substrates or nonsubstrate of the P-gp is important in drug development. Therefore to identify whether a compound is a P-gp substrate or not, in silico method is promising. Recursive Partitioning (RP) method was explored for prediction of P-gp substrate. A set of 261 compounds, including 146 substrates and 115 nonsubstrates of P-gp, was used to training and validation. Using molecular descriptors that we can interpret their own meaning, we have established two models for prediction of P-gp substrates. In the first model, we chose only 6 descriptors which have simple physical meaning. In the training set, the overall predictability of our model is 78.95%. In case of test set, overall predictability is 69.23%. Second model with 2D and 3D descriptors shows a little better predictability (overall predictability of training set is 79.29%, test set is 79.37%), the second model with 2D and 3D descriptors shows better discriminating power than first model with only 2D descriptors. This approach will be used to reduce the number of compounds required to be run in the P-gp efflux assay.

카오스 특성을 갖는 뇌파신호의 예측을 위한 신경회로망 설계에 관한 연구 (A Study on Design of Neural Network for the Prediction of EEG with Chaotic Characteristics)

  • 신창용;김택수;박상희
    • 대한의용생체공학회:학술대회논문집
    • /
    • 대한의용생체공학회 1995년도 춘계학술대회
    • /
    • pp.265-269
    • /
    • 1995
  • In this study, we present a training method of radial basis function networks based on recursive modified Gram-Schmidt algorithm for single step prediction of chaotic time series. With single step predictions of Mackey-Glass time series and alpha-rhythm EEG which has chaotic characteristics, the radial basis function network trained by this method is compared with one trained by a classical non-recursive method and the radial basis function model proposed by X.D. He and A. Lapedes. The results show the effectiveness of the training method.

  • PDF

이노베이션 상관관계 테스트를 이용한 잡음인식 (Identification of Noise Covariance by using Innovation Correlation Test)

  • 박성욱
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1992년도 하계학술대회 논문집 A
    • /
    • pp.305-307
    • /
    • 1992
  • This paper presents a technique, which identifies both process noise covariance and sensor noise covariance by using innovation correlation test. A correlation test, which checks whether the square root Kalman filter is workingly optimal or not, is given. The system is stochastic autoregressive moving-average model with auxiliary white noise Input. The linear quadratic Gaussian control is used for minimizing stochastic cost function. This paper indentifies Q, R, and estimates parametric matrics $A(q^{-1}),B(q^{-1}),C(q^{-1})$ by means of extended recursive least squares and model reference control. And The proposed technique has been validated in simulation results on the fourth order system.

  • PDF

시계열 분석 모형 및 머신 러닝 분석을 이용한 수출 증가율 장기예측 성능 비교 (Comparison of long-term forecasting performance of export growth rate using time series analysis models and machine learning analysis)

  • 남성휘
    • 무역학회지
    • /
    • 제46권6호
    • /
    • pp.191-209
    • /
    • 2021
  • In this paper, various time series analysis models and machine learning models are presented for long-term prediction of export growth rate, and the prediction performance is compared and reviewed by RMSE and MAE. Export growth rate is one of the major economic indicators to evaluate the economic status. And It is also used to predict economic forecast. The export growth rate may have a negative (-) value as well as a positive (+) value. Therefore, Instead of using the ReLU function, which is often used for time series prediction of deep learning models, the PReLU function, which can have a negative (-) value as an output value, was used as the activation function of deep learning models. The time series prediction performance of each model for three types of data was compared and reviewed. The forecast data of long-term prediction of export growth rate was deduced by three forecast methods such as a fixed forecast method, a recursive forecast method and a rolling forecast method. As a result of the forecast, the traditional time series analysis model, ARDL, showed excellent performance, but as the time period of learning data increases, the performance of machine learning models including LSTM was relatively improved.

이송 물체의 질량 측정 속도 향샹 (Improvements of Mass Measurement Rate for Moving Objects)

  • Lee, W.G.;Kim, K.P.
    • 한국정밀공학회지
    • /
    • 제12권11호
    • /
    • pp.110-117
    • /
    • 1995
  • This study presents and algorithm and related techniques which could satisfy the important properties of check weighers and conveyor scales. The algorithm of Recursive Least Squares Regression is applied for the weighing system simulated as a dynamic model of the second order. Using the model and the algorithm, model parameters and then the mass being weighed can be determined from the step input. The performance of the algorithm was tested on a check weigher. Discussions were extended to the development of noise reduction techniques and to the lagged introduction of objects on the moving plate. It turns out that the algorithm shows several desirable features suitable for real-time signal processing with a microcomputer, which are high precision and stability in noisy environment.

  • PDF

Recursive Design of Nonlinear Disturbance Attenuation Control for STATCOM

  • Liu Feng;Mei Shengwei;Lu Qiang;Goto Masno
    • International Journal of Control, Automation, and Systems
    • /
    • 제3권spc2호
    • /
    • pp.262-269
    • /
    • 2005
  • In this paper, a nonlinear robust control approach is applied to design a controller for the Static Synchronous Compensator (STATCOM). A robust control dynamic model of STATCOM in a one-machine, infinite-bus system is established with consideration of the torque disturbance acting on the rotating shaft of the generator set and the disturbance to the output voltage of STATCOM. A novel recursive approach is utilized to construct the energy storage function of the system such that the solution to the disturbance attenuation control problem is acquired, which avoids the difficulty involved in solving the Hamilton-Jacobi-Issacs (HJI) inequality. Sequentially, the nonlinear disturbance attenuation control strategy of STATCOM is obtained. Simulation results demonstrate that STATCOM with the proposed controller can more effectively improve the voltage stability, damp the oscillation, and enhance the transient stability of power systems compared to the conventional PI+PSS controller.

C의 재귀 호출로부터 동적 구조를 활용한 VHDL로의 변환 (Translation utilizing Dynamic Structure from Recursive Procedure & Function in C to VHDL)

  • 홍승완;이정아
    • 한국정보처리학회논문지
    • /
    • 제7권10호
    • /
    • pp.3247-3261
    • /
    • 2000
  • 하드웨어와 소프트웨어의 통합 설계 방법을 사용하면 다양한 신호처리 시스템을 설계 시간 및 비용에 있어서 효율적으로 구축 할 수 있다. 기존에 연구된 C로 구현된 다양한 신호 처리 시스템을 통합 설계 환경에서 효과적으로 활용하기 위하여 C로 구현된 알고리즘을 하드웨어 설계 언어(VHDL)로 변환할 필요성이 있다. C를 VHDL로 변환하는 경우 특히 동적 할당, 포인터, 재귀 호출 구문의 변환이 용이하지 않다. 본 논문에서는, 현재까지 소프트웨어로 구현되어 왔던 재귀 호출문을 동적 구조를 활용하여 VHDL 구문으로 변환하는 방법론을 제시하고자 한다. 이를 통해 통합 설계의 하드웨어 소프트웨어 분할시 유연성을 부여할 수 있고, 통합 설계의 궁극적인 목표인 시스템의 전체적인 성능 향상과 설계 시간 단축으로 우수한 목적 시스템을 구축할 수 있을 것으로 기대된다.

  • PDF

하위 훈련 성과 융합을 위한 순환적 계층 재귀 모델 (A Model of Recursive Hierarchical Nested Triangle for Convergence from Lower-layer Sibling Practices)

  • 문효정
    • 디지털콘텐츠학회 논문지
    • /
    • 제19권2호
    • /
    • pp.415-423
    • /
    • 2018
  • 최근, 컴퓨터 분야의 기계 학습(Machine Learning)과 딥러닝(Deep Learning) 등 컴퓨터 관련 학습이 각광을 받고 있다. 이들은 인공 신경망(Artificial Neural Network)을 이용하여 가장 하위 레벨로부터 학습을 시작하여, 최상위 레벨까지 그 결과를 전달하여 최종 결과를 산출하는 방식이다. 하위레벨로부터의 체계적인 학습을 통한 효과적인 성장 및 교육 방안에 대한 연구는 다양한 분야에서 이루어지고 있으나, 체계적인 규칙과 방법에 기반한 모델은 찾아보기가 힘들다. 이에, 본 논문에서는 성장 및 융합 모델인, TNT 모델(Transitive Nested Triangle Model)을 처음으로 제안한다. 제안하는 모델은 기하학적인 형태를 통해 형성된 각 기능들이 유기적 계층 관계를 형성하여, 상위로 성장 및 융합하면서, 그 결과가 반복 사용되는 순환적 재귀 모델이다. 즉, '수평적 형제 병합에 이은 상위로의 융합(Horizontal Sibling Merges and Upward Convergence)'의 분석적 방법이다. 이러한 모델은 공학, 디지털공학, 인문학, 예술학 등에 모두 적용될 수 있는 기본기적 이론으로, 본 연구에서는 제안하는 TNT 모델을 설명하는 것에 그 초점을 둔다.