• Title/Summary/Keyword: Multi-class

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Multi-class support vector machines for paint condition assessment on the Sydney Harbour Bridge using hyperspectral imaging

  • Huynh, Cong Phuoc;Mustapha, Samir;Runcie, Peter;Porikli, Fatih
    • Structural Monitoring and Maintenance
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    • v.2 no.3
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    • pp.181-197
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    • 2015
  • Assessing the condition of paint on civil structures is an important but challenging and costly task, in particular when it comes to large and complex structures. Current practices of visual inspection are labour-intensive and time-consuming to perform. In addition, this task usually relies on the experience and subjective judgment of individual inspectors. In this study, hyperspectral imaging and classification techniques are proposed as a method to objectively assess the state of the paint on a civil or other structure. The ultimate objective of the work is to develop a technology that can provide precise and automatic grading of paint condition and assessment of degradation due to age or environmental factors. Towards this goal, we acquired hyperspectral images of steel surfaces located at long (mid-range) and short distances on the Sydney Harbour Bridge with an Acousto-Optics Tunable filter (AOTF) hyperspectral camera (consisting of 21 bands in the visible spectrum). We trained a multi-class Support Vector Machines (SVM) classifier to automatically assess the grading of the paint from hyperspectral signatures. Our results demonstrate that the classifier generates highly accurate assessment of the paint condition in comparison to the judgement of human experts.

Comparison of Loss Function for Multi-Class Classification of Collision Events in Imbalanced Black-Box Video Data (불균형 블랙박스 동영상 데이터에서 충돌 상황의 다중 분류를 위한 손실 함수 비교)

  • Euisang Lee;Seokmin Han
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.24 no.1
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    • pp.49-54
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    • 2024
  • Data imbalance is a common issue encountered in classification problems, stemming from a significant disparity in the number of samples between classes within the dataset. Such data imbalance typically leads to problems in classification models, including overfitting, underfitting, and misinterpretation of performance metrics. Methods to address this issue include resampling, augmentation, regularization techniques, and adjustment of loss functions. In this paper, we focus on loss function adjustment, particularly comparing the performance of various configurations of loss functions (Cross Entropy, Balanced Cross Entropy, two settings of Focal Loss: 𝛼 = 1 and 𝛼 = Balanced, Asymmetric Loss) on Multi-Class black-box video data with imbalance issues. The comparison is conducted using the I3D, and R3D_18 models.

Class 4 Active RFID Multi-hop Relay System based on IEEE 802.15.4a Low-Rate UWB in Sensor Network

  • Zhang, Hong;Hong, Sung-Hyun;Chang, Kyung-Hi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.3
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    • pp.258-272
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    • 2010
  • The low-rate (LR) UWB is a promising technology for the ubiquitous sensor network (USN) due to its extremely low power consumption and simple transceiver implementation. However the limited communication range is a bottleneck for its widespread use. This paper deals with a new frame structure of class 4 active RFID multi-hop relay system based on ISO/IEC 18000-7 standard integrating with IEEE 802.15.4a LR-UWB PHY layer specification, which sets up a connection to USN. As a result of the vital importance of the coverage and throughput in the application of USN, further we analyze the performance of the proposed system considered both impulse radio UWB (IR-UWB) and chirp spread spectrum (CSS). Our simulation results show that the coverage and throughput are remarkably increased.

Incremental Multi-classification by Least Squares Support Vector Machine

  • Oh, Kwang-Sik;Shim, Joo-Yong;Kim, Dae-Hak
    • Journal of the Korean Data and Information Science Society
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    • v.14 no.4
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    • pp.965-974
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    • 2003
  • In this paper we propose an incremental classification of multi-class data set by LS-SVM. By encoding the output variable in the training data set appropriately, we obtain a new specific output vectors for the training data sets. Then, online LS-SVM is applied on each newly encoded output vectors. Proposed method will enable the computation cost to be reduced and the training to be performed incrementally. With the incremental formulation of an inverse matrix, the current information and new input data are used for building another new inverse matrix for the estimation of the optimal bias and lagrange multipliers. Computational difficulties of large scale matrix inversion can be avoided. Performance of proposed method are shown via numerical studies and compared with artificial neural network.

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A Study on Output Voltage Stabilization of 20W Class Multi-output QR Flyback Converter for Auxiliary Power (20W급 보조전원용 다출력 QR 플라이백 컨버터의 출력전압 안정화에 관한 연구)

  • Yoo, Jeong Sang;Gil, Yong Man;Kim, Hyun Bae;Ahn, Tae Young
    • Journal of the Semiconductor & Display Technology
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    • v.20 no.3
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    • pp.157-160
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    • 2021
  • In this paper, a 20W class multi-output QR flyback converter for auxiliary power supply was designed to stabilize 4 output voltages, and the efficiency and load characteristics were compared and analyzed. It was checked if each output affects other output characteristics through experiment. As a result, the experimental circuit reached a high efficiency of 82.5% or more at a load power of over 20W, and the maximum power loss was 2.6W. Consequently, it was confirmed that all of 4 output voltages of the multi-output QR flyback converter constructed in this paper were stabilized within 0.5% in full-load range, and each output was independently controlled in an electrically isolated state.

SOLVABILITY OF MULTI-POINT BOUNDARY VALUE PROBLEMS FOR FRACTIONAL DIFFERENTIAL EQUATIONS AT RESONANCE

  • Liu, Yuji;Liu, Xingyuan
    • Journal of the Chungcheong Mathematical Society
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    • v.25 no.3
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    • pp.425-443
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    • 2012
  • Sufficient conditions for the existence of at least one solution of a class of multi-point boundary value problems of the fractional differential equations at resonance are established. The main theorem generalizes and improves those ones in [Liu, B., Solvability of multi-point boundary value problems at resonance(II), Appl. Math. Comput., 136(2003)353-377], see Remark 2.3. An example is presented to illustrate the main results.

SOME MULTI-SUBLINEAR OPERATORS ON GENERALIZED MORREY SPACES WITH NON-DOUBLING MEASURES

  • Shi, Yanlong;Tao, Xiangxing
    • Journal of the Korean Mathematical Society
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    • v.49 no.5
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    • pp.907-925
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    • 2012
  • In this paper the boundedness for a large class of multi-sublinear operators is established on product generalized Morrey spaces with non-doubling measures. As special cases, the corresponding results for multilinear Calder$\acute{o}$n-Zygmund operators, multilinear fractional integrals and multi-sublinear maximal operators will be obtained.

A New Approach to Reduced-Order Modeling of Multi-Module Converters

  • Park, Byung-Cho
    • Journal of Electrical Engineering and information Science
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    • v.2 no.4
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    • pp.92-98
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    • 1997
  • This paper presents a new approach to obtaining a reduced-order model for multi-module converters. The proposed approach can be used to derive the reduced-order model for a wide class of multi-module converters including pulse-width-modulated (PWM) converters, soft-switched PWM converters, and resonant converters. The reduced-order model has the structure of a conventional single-module converter while preserving the dynamics of the original multi-module converter. Derivation procedures and the use of the reduced-order model is demonstrated using a three-module boost converter.

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Design and Implementation of a Class Library Manager for Application Builders (어플리케이션 빌더용 클래스 라이브러리 관리자에 대한 설계 및 구현)

  • Lee, Chi-Kuhn;Kim, Joon-Ha
    • IE interfaces
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    • v.8 no.3
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    • pp.11-23
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    • 1995
  • During the past few years, the productivity has been considered as one of the most important aims in developing softwares. Many practitioners and theorists are trying reuse ready made codes to increase the productivity of software development and the quality of their products. This paper introduces our experiences in developing a highly reusable class library and its reusing environment for building a database interface application. And the concepts, Structured Multi-Library and Dual Views of Class Inheritance, are also suggested, which consist our main conceptual framework in our work. Details in implementation are discussed in brief at the end.

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Optimal Solution of Classification (Prediction) Problem

  • Mohammad S. Khrisat
    • International Journal of Computer Science & Network Security
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    • v.23 no.9
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    • pp.129-133
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    • 2023
  • Classification or prediction problem is how to solve it using a specific feature to obtain the predicted class. A wheat seeds specifications 4 3 classes of seeds will be used in a prediction process. A multi linear regression will be built, and a prediction error ratio will be calculated. To enhance the prediction ratio an ANN model will be built and trained. The obtained results will be examined to show how to make a prediction tool capable to compute a predicted class number very close to the target class number.