• Title/Summary/Keyword: active learning

Search Result 1,192, Processing Time 0.032 seconds

The development of semi-active suspension controller based on error self recurrent neural networks (오차 자기순환 신경회로망 기반 반능동 현가시스템 제어기 개발)

  • Lee, Chang-Goo;Song, Kwang-Hyun
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.5 no.8
    • /
    • pp.932-940
    • /
    • 1999
  • In this paper, a new neural networks and neural network based sliding mode controller are proposed. The new neural networks are an mor self-recurrent neural networks which use a recursive least squares method for the fast on-line leammg. The error self-recurrent neural networks converge considerably last than the back-prollagation algorithm and have advantage oi bemg less affected by the poor initial weights and learning rate. The controller for suspension system is designed according to sliding mode technique based on new proposed neural networks. In order to adapt shding mode control mnethod, each frame dstance hetween ground and vehcle body is estimated md controller is designed according to estimated neural model. The neural networks based sliding mode controller approves good peiformance throllgh computer sirnulations.

  • PDF

Human Iris Recognition using Wavelet Transform and Neural Network

  • Cho, Seong-Won;Kim, Jae-Min;Won, Jung-Woo
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.3 no.2
    • /
    • pp.178-186
    • /
    • 2003
  • Recently, many researchers have been interested in biometric systems such as fingerprint, handwriting, key-stroke patterns and human iris. From the viewpoint of reliability and robustness, iris recognition is the most attractive biometric system. Moreover, the iris recognition system is a comfortable biometric system, since the video image of an eye can be taken at a distance. In this paper, we discuss human iris recognition, which is based on accurate iris localization, robust feature extraction, and Neural Network classification. The iris region is accurately localized in the eye image using a multiresolution active snake model. For the feature representation, the localized iris image is decomposed using wavelet transform based on dyadic Haar wavelet. Experimental results show the usefulness of wavelet transform in comparison to conventional Gabor transform. In addition, we present a new method for setting initial weight vectors in competitive learning. The proposed initialization method yields better accuracy than the conventional method.

Multiple-Channel Active Noise Control by ANFIS and Independent Component Analysis without Secondary Path Modeling

  • Kim, Eung-Ju;Lee, Sang-yup;Kim, Beom-Soo;Lim, Myo-Taeg
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2001.10a
    • /
    • pp.22.1-22
    • /
    • 2001
  • In this paper we present Multiple-Channel Active Noise Control[ANC] system by employing Independent Component Analysis[ICA] and Adaptive Network Fuzzy Inference System[ANFIS]. ICA is widely used in signal processing and communication and it use prewhiting and appropriate choice of non-linearities, ICA can separate mixed signal. ANFIS controller is trained with the hybrid learning algorithm to optimize its parameters for adaptively canceling noise. This new method which minimizes a statistical dependency of mutual information(MI) in mixed low frequency noise signal and there is no need to secondary path modeling. The proposed implementations achieve more powerful and stable noise reduction than Filtered-X LMS algorithms which is needed for LTI assumption and precise secondary error

  • PDF

Refinement of Ground Truth Data for X-ray Coronary Artery Angiography (CAG) using Active Contour Model

  • Dongjin Han;Youngjoon Park
    • International journal of advanced smart convergence
    • /
    • v.12 no.4
    • /
    • pp.134-141
    • /
    • 2023
  • We present a novel method aimed at refining ground truth data through regularization and modification, particularly applicable when working with the original ground truth set. Enhancing the performance of deep neural networks is achieved by applying regularization techniques to the existing ground truth data. In many machine learning tasks requiring pixel-level segmentation sets, accurately delineating objects is vital. However, it proves challenging for thin and elongated objects such as blood vessels in X-ray coronary angiography, often resulting in inconsistent generation of ground truth data. This method involves an analysis of the quality of training set pairs - comprising images and ground truth data - to automatically regulate and modify the boundaries of ground truth segmentation. Employing the active contour model and a recursive ground truth generation approach results in stable and precisely defined boundary contours. Following the regularization and adjustment of the ground truth set, there is a substantial improvement in the performance of deep neural networks.

Design and Implementation of the Smart Clicker for Active Learning (액티브 러닝을 위한 스마트 클리커의 설계 및 구현)

  • Kim, Eun-Gyung;Koo, Bon-Chul;Kim, Young-Jin;Kim, Jin-Hwan;Park, Je-Yeong;Jeong, Se-Hee
    • Journal of Practical Engineering Education
    • /
    • v.5 no.2
    • /
    • pp.101-107
    • /
    • 2013
  • Clickers that are personal response systems are a technology used to promote active learning and most research on the benefits of using clickers has shown that students become engaged and enjoy using them. But, existing clickers consisting of hardware devices and aggregation software provide simple response and aggregation function and it costs a lot. In this paper, in order to resolve the limitation of the existing clickers, we've designed and implemented the Smart Clicker consisting of a smartphone application for students and a web application & a MFC program for professors. Students can answer professor's questions with O/X or numbers or text and even ask questions with text messaging by using Smart Clicker in the classroom. Professors can see students' answers or questions immediately and check up students' response participation rate on the web page. Besides, the Smart Clicker will help professors actively engage students during the entire class period and gauge their level of understanding of the material being presented, and provide prompt feedback to student questions. As a result, we expect that quality of education will be increased.

Real-time Active Vibration Control of Smart Structure Using Adaptive PPF Controller (적응형 PPF 제어기를 이용한 지능구조물의 실시간 능동진동제어)

  • Heo, Seok;Lee, Seung-Bum;Kwak, Moon-Kyu;Baek, Kwang-Hyun
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.14 no.4
    • /
    • pp.267-275
    • /
    • 2004
  • This research is concerned with the development of a real-time adaptive PPF controller for the active vibration suppression of smart structure. In general, the tuning of the PPF controller is carried out off-line. In this research, the real-time learning algorithm is developed to find the optimal filter frequency of the PPF controller in real time and the efficacy of the algorithm is proved by implementing it in real time. To this end, the adaptive algorithm is developed by applying the gradient descent method to the predefined performance index, which is similar to the method used popularly in the optimization and neural network controller design. The experiment was carried out to verify the validity of the adaptive PPF controller developed in this research. The experimental results showed that adaptive PPF controller is effective for active vibration control of the structure which is excited by either impact or harmonic disturbance. The filter frequency of the PPF controller is tuned in a very short period of time thus proving the efficiency of the adaptive PPF controller.

An Effective Implementation Method for Dual Use of Web-based Multidimensional Interactive Digital Contents (웹기반 다차원 민군겸용 인터액티브 디지털 콘텐츠의 효과적인 구현 방안)

  • Gang, Seok-Hun;Kim, Dae-Cheong
    • Journal of National Security and Military Science
    • /
    • s.3
    • /
    • pp.197-242
    • /
    • 2005
  • Active catalog is a kind of digital content that enables consumers to test the functions and features of products from their PCs as if they were using it in real life, by simulating the actions and responses of the product. This new type of interactive digital content can be used extensively to make sales personnel training manuals, sales tools, user manuals and user trouble shooting documents. With active catalogs, companies will be able to compare different designs, show actions according to different functions, and evaluate user reaction to new products without having to produce a single physical prototype or mock-up. At the same time, consumers will be able to understand and 'operate' the product and make well-informed purchase decisions. In this paper, we present a visual event-driven modeling tool, PlayMo, for creating active catalogs, analyze the advantages of using PlayMo, describe the event-driven method used by PlayMo and also introduce two enhanced characteristics of the Event Flow Chart with which the events in PlayMo are structured. Interactive digital content by using the PlayMo3D makes easy, simple and effective design for e-learning, e-catalogue, e-marketing/sales, e-prototyping, customer support, etc. Through its application-ready 3D function visualization solution, engineers and designers can rapidly turn a CAD design model into a 3D interactive virtual product, and the effective function prototyping job can be also completed within a minute.

  • PDF

Confidence Measure of Depth Map for Outdoor RGB+D Database (야외 RGB+D 데이터베이스 구축을 위한 깊이 영상 신뢰도 측정 기법)

  • Park, Jaekwang;Kim, Sunok;Sohn, Kwanghoon;Min, Dongbo
    • Journal of Korea Multimedia Society
    • /
    • v.19 no.9
    • /
    • pp.1647-1658
    • /
    • 2016
  • RGB+D database has been widely used in object recognition, object tracking, robot control, to name a few. While rapid advance of active depth sensing technologies allows for the widespread of indoor RGB+D databases, there are only few outdoor RGB+D databases largely due to an inherent limitation of active depth cameras. In this paper, we propose a novel method used to build outdoor RGB+D databases. Instead of using active depth cameras such as Kinect or LIDAR, we acquire a pair of stereo image using high-resolution stereo camera and then obtain a depth map by applying stereo matching algorithm. To deal with estimation errors that inevitably exist in the depth map obtained from stereo matching methods, we develop an approach that estimates confidence of depth maps based on unsupervised learning. Unlike existing confidence estimation approaches, we explicitly consider a spatial correlation that may exist in the confidence map. Specifically, we focus on refining confidence feature with the assumption that the confidence feature and resultant confidence map are smoothly-varying in spatial domain and are highly correlated to each other. Experimental result shows that the proposed method outperforms existing confidence measure based approaches in various benchmark dataset.

Target/non-target classification using active sonar spectrogram image and CNN (능동소나 스펙트로그램 이미지와 CNN을 사용한 표적/비표적 식별)

  • Kim, Dong-Wook;Seok, Jong-Won;Bae, Keun-Sung
    • Journal of IKEEE
    • /
    • v.22 no.4
    • /
    • pp.1044-1049
    • /
    • 2018
  • CNN (Convolutional Neural Networks) is a neural network that models animal visual information processing. And it shows good performance in various fields. In this paper, we use CNN to classify target and non-target data by analyzing the spectrogram of active sonar signal. The data were divided into 8 classes according to the ratios containing the targets and used for learning CNN. The spectrogram of the signal is divided into frames and used as inputs. As a result, it was possible to classify the target and non-target using the characteristic that the classification results of the seven classes corresponding to the target signal sequentially appear only at the position of the target signal.

GA-BASED PID AND FUZZY LOGIC CONTROL FOR ACTIVE VEHICLE SUSPENSION SYSTEM

  • Feng, J.-Z.;Li, J.;Yu, F.
    • International Journal of Automotive Technology
    • /
    • v.4 no.4
    • /
    • pp.181-191
    • /
    • 2003
  • Since the nonlinearity and uncertainties which inherently exist in vehicle system need to be considered in active suspension control law design, this paper proposes a new control strategy for active vehicle suspension systems by using a combined control scheme, i.e., respectively using a genetic algorithm (GA) based self-tuning PID controller and a fuzzy logic controller in two loops. In the control scheme, the PID controller is used to minimize vehicle body vertical acceleration, the fuzzy logic controller is to minimize pitch acceleration and meanwhile to attenuate vehicle body vertical acceleration further by tuning weighting factors. In order to improve the adaptability to the changes of plant parameters, based on the defined objectives, a genetic algorithm is introduced to tune the parameters of PID controller, the scaling factors, the gain values and the membership functions of fuzzy logic controller on-line. Taking a four degree-of-freedom nonlinear vehicle model as example, the proposed control scheme is applied and the simulations are carried out in different road disturbance input conditions. Simulation results show that the present control scheme is very effective in reducing peak values of vehicle body accelerations, especially within the most sensitive frequency range of human response, and in attenuating the excessive dynamic tire load to enhance road holding performance. The stability and adaptability are also showed even when the system is subject to severe road conditions, such as a pothole, an obstacle or a step input. Compared with conventional passive suspensions and the active vehicle suspension systems by using, e.g., linear fuzzy logic control, the combined PID and fuzzy control without parameters self-tuning, the new proposed control system with GA-based self-learning ability can improve vehicle ride comfort performance significantly and offer better system robustness.