• 제목/요약/키워드: separability

검색결과 154건 처리시간 0.024초

저널베어링 상태 진단을 위한 최적의 데이터 분석 기준 설정 (Optimal Datum Unit Definition for Diagnostics of Journal Bearing System)

  • 윤병동;정준하;전병철;김연환;배용채
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.84-89
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    • 2014
  • Data-driven method for fault diagnostics system often use machine learning technique. To use such technique proper signal processing should be implemented such as time synchronous averaging (TSA) for ball bearing systems. However, for journal bearing diagnostics systems not much has been researched, and yet a proper signal processing method has not been studied. Therefore, in this research an optimal datum unit for a reliable journal bearing diagnostics system along with angular resampling process is being suggested. Before extracting time and frequency domain features, angular resampling is applied to each cycle of vibration data. As to preserve the characteristics of vibration signal, averaging method is replaced by finding the optimal datum unit which strengthens statistical characteristics of vibration signal. Then 20 features were extracted for various cases, and those features are being evaluated by two criteria, separability and classification accuracy.

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Sensitive and Mild Fluorogenic Reagents for Biogenic Carboxylic Acids in HPLC

  • Ushijima, Tamano;Saito, Mikihiko;Sasamoto, Kazumi;Ohkura, Yosuke;Ueno, Keiyu
    • 분석과학
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    • 제8권4호
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    • pp.545-551
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    • 1995
  • Five acid hydrazides as precolumn fluorescence derivatization reagents for carboxylic acids in HPLC, which have the benzofuran or benzothiazole moiety conjugated to a furan, thiophene or oxazoline ring, were synthesized and examined in view of reactivity, separability and sensitivity. Of these hydrazides, 2-(5-hydrazinocarbonyl-2-oxazolyl)-5,6-dimethoxybenzothiazole (BTOH) was most favorable. The detection limit of lauric acid as a model acid was 0.1 pmol per $10-{\mu}l$ injection volume at S/N=3, which was roughly equal to that of an analogous compound, 2-(5-hydrazinocarbonyl-2-furyl)-5,6-dimethoxybenzothiazole. The reagent allowed rapid assays of carboxylic acids ($C_{12:0}-C_{20:4}$) within 20 min with satisfactory scparability. The method was applied to the determination of fatty acids in human sera from healthy volunteers as well as from patients with diabetes or thyroid dysfunction.

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Fractal 기하학을 이용한 균사의 성장과 구체 형성의 특성 분석 (Analysis of Filamentous Fungal Growth and Pellets Formation by Fractal Geometry)

  • 류두현
    • KSBB Journal
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    • 제9권5호
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    • pp.512-517
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    • 1994
  • 균류를 이용하는 생물공정의 생산성, 분리성, 유변 학적 성질에 영향을 주는 중요한 변수인 균류의 형 태를 fractal 차원을 사용하여 정량화하였다. 산업적 으로 중요한 균류인 Aspegillus oryzae와 Aspergil­l Ius niger가 초기의 접종 포자량과 탄소원의 농도를 변화시켜 액상배지에서 성장하는 경우, 디지탈 영상 분석장치를 사용하여 fractal 차원을 계산하였다. 균 사가 형성하는 구체의 특성과 fractal로 표현된 균사 의 형태와의 상관관계를 구하였다. 일반적으로 낮은 fractal 차원의 균사가 낮은 멜도(compactness)의 구체를 형성하고 외부의 모양이 불규칙적이었다.

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자기검사 Pulse별 잉여수연산회로를 이용한 고신뢰화 Fault Tolerant 디지털필터의 구성에 관한 연구 (Implementation of High Reliable Fault-Tolerant Digital Filter Using Self-Checking Pulse-Train Residue Arithmetic Circuits)

  • 김문수;손동인;전구제
    • 대한전자공학회논문지
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    • 제25권2호
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    • pp.204-210
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    • 1988
  • The residue number system offers the possibility of high-speed operation and error detection/correction because of the separability of arithmetic operations on each digit. A compact residue arithmetic module named the self-checking pulse-train residue arithmetic circuit is effectively employed as the basic module, and an efficient error detection/correction algorithm in which error detection is performed in each basic module and error correction is performed based on the parallelism of residue arithmetic is also employed. In this case, the error correcting circuit is imposed in series to non-redundant system. This design method has an advantage of compact hardware. Following the proposed method, a 2nd-order recursive fault-tolerant digital filter is practically implemented, and its fault-tolerant ability is proved by noise injection testing.

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Multiresolution Independent Component Analysis for Iris Identification

  • Noh, Seung-In;Kwanghuk Pae;Lee, Chulhan;Kim, Jaihie
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -3
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    • pp.1674-1677
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    • 2002
  • In this paper, the new method to extract the features of iris signals is proposed; Multiresolution ICA (M-ICA) provides good properties to represent signals with time-frequency. The conventional methods were to use the technique of filter bank analysis, while ICA is unsupervised learning algorithm using high-order statistics. M-ICA could make use of strengths of learn- ing method and multiresolution. Also, we performed comparative studies of different feature extraction techniques applied to personal identification using iris pat- tern. To measure goodness of methods, we use Fisher’s discriminant ratio to quantify the class-separability of features generated by various techniques.

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Hybrid Pattern Recognition Using a Combination of Different Features

  • Choi, Sang-Il
    • 한국컴퓨터정보학회논문지
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    • 제20권11호
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    • pp.9-16
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    • 2015
  • We propose a hybrid pattern recognition method that effectively combines two different features for improving data classification. We first extract the PCA (Principal Component Analysis) and LDA (Linear Discriminant Analysis) features, both of which are widely used in pattern recognition, to construct a set of basic features, and then evaluate the separability of each basic feature. According to the results of evaluation, we select only the basic features that contain a large amount of discriminative information for construction of the combined features. The experimental results for the various data sets in the UCI machine learning repository show that using the proposed combined features give better recognition rates than when solely using the PCA or LDA features.

음악에 따른 감정분류을 위한 EEG특징벡터 비교 (Comparison of EEG Feature Vector for Emotion Classification according to Music Listening)

  • 이소민;변성우;이석필
    • 전기학회논문지
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    • 제63권5호
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    • pp.696-702
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    • 2014
  • Recently, researches on analyzing relationship between the state of emotion and musical stimuli using EEG are increasing. A selection of feature vectors is very important for the performance of EEG pattern classifiers. This paper proposes a comparison of EEG feature vectors for emotion classification according to music listening. For this, we extract some feature vectors like DAMV, IAV, LPC, LPCC from EEG signals in each class related to music listening and compare a separability of the extracted feature vectors using Bhattacharyya distance. So more effective feature vectors are recommended for emotion classification according to music listening.

다중 거칠기 벡터와 통계적 분류기를 이용한 초음파 간 영상 분류에 관한 연구 (A Study on the Classification of Ultrasonic Liver Images Using Multi Texture Vectors and a Statistical Classifier)

  • 정정원;김동윤
    • 대한의용생체공학회:의공학회지
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    • 제17권4호
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    • pp.433-442
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    • 1996
  • Since one texture property(i.e coarseness, orientation, regularity, granularity) for ultrasound liver ages was not sufficient enough to classify the characteristics of livers, we used multi texture vectors tracted from ultrasound liver images and a statistical classifier. Multi texture vectors are selected among the feature vectors of the normal liver, fat liver and cirrhosis images which have a good separability in those ultrasound liver images. The statistical classifier uses multi texture vectors as input vectors and classifies ultrasound liver images for each multi texture vector by the Bayes decision rule. Then the decision of the liver disease is made by choosing the maximum value from the averages of a posteriori probability for each multi texture vector In our simulation, we obtained higtler correct ratio than that of other methods using single feature vector, for the test set the correct ratio is 94% in the normal liver, 84% in the fat liver and 86% in the cirrhosis liver.

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Synergic Effect of using the Optical and Radar Image Data for the Land Cover Classification in Coastal Region

  • Kim, Sun-Hwa;Lee, Kyu-Sung
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1030-1032
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    • 2003
  • This study a imed to analyze the effect of combined optical and radar image for the land cover classification in coastal region. The study area, Gyeonggi Bay area has one of the largest tidal ranges and has frequent land cover changes due to the several reclamations and rather intensive land uses. Ten land cover types were classified using several datasets of combining Landsat ETM+ and RADARSAT imagery. The synergic effects of the merged datasets were analyzed by both visual interpretation and an ordinary supervised classification. The merged optical and SAR datasets provided better discrimination among the land cover classes in the coastal area. The overall classification accuracy of merged datasets was improved to 86.5% as compared to 78% accuracy of using ETM+ only.

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서비스 개념을 둘러싼 최근논의에 대한 비판적 고찰 (A Critical Examination of Recent Studies On the Definition of Services)

  • 서환주
    • 한국IT서비스학회지
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    • 제7권4호
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    • pp.287-300
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    • 2008
  • Our Study aims to examine, from a critical perspective, recent approaches to the definition of services, Studies that deal with the question of how to characterize services offer three types of response. The first approach developed by classical economists proposes to use technical criteria (immateriality, non-separability between consumption and production, non-storage, heterogeneity) as foundation for a specific definition of services. The second, which is today most widely cited definition, that of Peter Hill proposes an institutional or a relation-oriented definition which emphasizes service triangle. Finally, the work of Gadrey, which investigates the impact of new technologies on service activities, offers a new general definition of services that is compatible with the existence of several demand rationales.