• 제목/요약/키워드: Feature Collection

검색결과 194건 처리시간 0.027초

문헌빈도와 장서빈도를 이용한 kNN 분류기의 자질선정에 관한 연구 (A Study on Feature Selection for kNN Classifier using Document Frequency and Collection Frequency)

  • 이용구
    • 한국도서관정보학회지
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    • 제44권1호
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    • pp.27-47
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    • 2013
  • 이 연구에서는 자동 색인을 통해 쉽게 얻을 수 있는 자질의 문헌빈도와 장서빈도를 이용하여 자동분류에서 자질 선정 기법을 kNN 분류기에 적용하였을 때, 어떠한 분류성능을 보이는지 알아보고자 하였다. 실험집단으로 한국일보-20000(HKIB-20000)의 일부를 이용하였다. 실험 결과 첫째, 장서빈도를 이용하여 고빈도 자질을 선정하고 저빈도 자질을 제거한 자질선정 방법이 문헌빈도보다 더 좋은 성능을 가져오는 것으로 나타났다. 둘째, 문헌빈도와 장서빈도 모두 저빈도 자질을 우선으로 선정하는 방법은 좋은 분류성능을 가져오지 못했다. 셋째, 장서빈도와 같은 단순빈도에서 자질 선정 구간을 조정하는 것이 문헌빈도와 장서빈도의 조합보다 더 좋은 성능을 가져오는 것으로 나타났다.

Indoor Path Recognition Based on Wi-Fi Fingerprints

  • Donggyu Lee;Jaehyun Yoo
    • Journal of Positioning, Navigation, and Timing
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    • 제12권2호
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    • pp.91-100
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    • 2023
  • The existing indoor localization method using Wi-Fi fingerprinting has a high collection cost and relatively low accuracy, thus requiring integrated correction of convergence with other technologies. This paper proposes a new method that significantly reduces collection costs compared to existing methods using Wi-Fi fingerprinting. Furthermore, it does not require labeling of data at collection and can estimate pedestrian travel paths even in large indoor spaces. The proposed pedestrian movement path estimation process is as follows. Data collection is accomplished by setting up a feature area near an indoor space intersection, moving through the set feature areas, and then collecting data without labels. The collected data are processed using Kernel Linear Discriminant Analysis (KLDA) and the valley point of the Euclidean distance value between two data is obtained within the feature space of the data. We build learning data by labeling data corresponding to valley points and some nearby data by feature area numbers, and labeling data between valley points and other valley points as path data between each corresponding feature area. Finally, for testing, data are collected randomly through indoor space, KLDA is applied as previous data to build test data, the K-Nearest Neighbor (K-NN) algorithm is applied, and the path of movement of test data is estimated by applying a correction algorithm to estimate only routes that can be reached from the most recently estimated location. The estimation results verified the accuracy by comparing the true paths in indoor space with those estimated by the proposed method and achieved approximately 90.8% and 81.4% accuracy in two experimental spaces, respectively.

Prototype-based Classifier with Feature Selection and Its Design with Particle Swarm Optimization: Analysis and Comparative Studies

  • Park, Byoung-Jun;Oh, Sung-Kwun
    • Journal of Electrical Engineering and Technology
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    • 제7권2호
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    • pp.245-254
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    • 2012
  • In this study, we introduce a prototype-based classifier with feature selection that dwells upon the usage of a biologically inspired optimization technique of Particle Swarm Optimization (PSO). The design comprises two main phases. In the first phase, PSO selects P % of patterns to be treated as prototypes of c classes. During the second phase, the PSO is instrumental in the formation of a core set of features that constitute a collection of the most meaningful and highly discriminative coordinates of the original feature space. The proposed scheme of feature selection is developed in the wrapper mode with the performance evaluated with the aid of the nearest prototype classifier. The study offers a complete algorithmic framework and demonstrates the effectiveness (quality of solution) and efficiency (computing cost) of the approach when applied to a collection of selected data sets. We also include a comparative study which involves the usage of genetic algorithms (GAs). Numerical experiments show that a suitable selection of prototypes and a substantial reduction of the feature space could be accomplished and the classifier formed in this manner becomes characterized by low classification error. In addition, the advantage of the PSO is quantified in detail by running a number of experiments using Machine Learning datasets.

A Novel Statistical Feature Selection Approach for Text Categorization

  • Fattah, Mohamed Abdel
    • Journal of Information Processing Systems
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    • 제13권5호
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    • pp.1397-1409
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    • 2017
  • For text categorization task, distinctive text features selection is important due to feature space high dimensionality. It is important to decrease the feature space dimension to decrease processing time and increase accuracy. In the current study, for text categorization task, we introduce a novel statistical feature selection approach. This approach measures the term distribution in all collection documents, the term distribution in a certain category and the term distribution in a certain class relative to other classes. The proposed method results show its superiority over the traditional feature selection methods.

차량후면부 차량특징정보 검출을 통한 차량정보인식 및 자동과금시스템 (Vehicle Information Recognition and Electronic Toll Collection System with Detection of Vehicle feature Information in the Rear-Side of Vehicle)

  • 이응주
    • 한국멀티미디어학회논문지
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    • 제7권1호
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    • pp.35-43
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    • 2004
  • 본 논문에서는 고속도로나 도심 진입 차량의 무인 자동과금 및 주요시설 출입 차량의 통제와 관리를 위하여 차량번호판 인식뿐만 아니라 차량 표시 문자와 제조사 식별자 검출 분류하여 차량의 정보를 판독하는 차량정보인식 및 자동과금시스템을 제안하였다. 제안한 알고리즘은 차량 후면부에서 획득된 영상으로부터 잡음제거, 세선화 등의 전처리 과정을 수행하고 템플릿 마스킹 및 레이블링 연산처리를 수행하여 차량표시문자, 제조사 표식자 및 번호판 영역을 각각 검출하였다. 또한, 검출된 특징 영역으로부터 특징자의 구조적 특징 및 패턴정보를 이용하여 표시문자와 제조사 표식자를 분류하였고, 하이브리드 패턴벡터와 세븐세그먼트 패턴벡터를 사용하여 차량번호판의 문자 및 숫자를 각각 인식하였다. 실험에서는 실제 고속도로상에서 제안한 차량인식 시스템에서 획득된 실 영상을 사용하여 인식 성능을 수행하였다. 실험 결과 제안한 알고리즘이 잡음, 외부환경, 차량의 크기에 무관하게 차량 특징자를 정확히 검출 분류하였으며 제안한 시스템은 범죄차량 단속, 차량자동과금 및 관공서 등의 차량입출력 관리의 무인화에 적용이 가능하다.

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Analysis of cellular fatty acid methyl esters (FAMEs) for the identification of leuconostoc strains isolated from kimchi

  • Lee, Jung-Sook;Chun, Chang-Ouk;Kim, Hong-Joong;Joo, Yun-Jung;Lee, Hun-Joo;Park, Chan-Sum;Park, Yong-Ha;Mheen, Tae-Ick
    • Journal of Microbiology
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    • 제34권3호
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    • pp.225-228
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    • 1996
  • The cellular fatty acid methyl esters (FAMEs) analysis data obtained for clusters defined at a Euclidian distance of 17.5, in the classification of lactic acid bacteria isolated from kimchi, described by Lee et al. (4), was used for the identification of 79 Leuconostoc isolates. The test strains were isolated using a selective isolation medium specific for the genus Leuconostoc. These strains were then characterized according to their fatty acid profiles. The results show that all seventy nine test strains were identified to the known Leuconostoc clusters B, C, and D. Cluster B had the highest relative amount of the saturated fatty acid 16 : 0. The saturated fatty acid 16 : 0 and summed feature 9 were found as a major components in cluster C, which had a higher level of summed feature 9 than cluster B. Cluster D is characterized by the highest relative amount of the unsaturated fatty acid 18 : 1 w9c. It is suggested that FAMEs analysis can be successfully applied in the identification of lactic acid bacteria isolated from kimchi.

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Feature Voting for Object Localization via Density Ratio Estimation

  • Wang, Liantao;Deng, Dong;Chen, Chunlei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제13권12호
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    • pp.6009-6027
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    • 2019
  • Support vector machine (SVM) classifiers have been widely used for object detection. These methods usually locate the object by finding the region with maximal score in an image. With bag-of-features representation, the SVM score of an image region can be written as the sum of its inside feature-weights. As a result, the searching process can be executed efficiently by using strategies such as branch-and-bound. However, the feature-weight derived by optimizing region classification cannot really reveal the category knowledge of a feature-point, which could cause bad localization. In this paper, we represent a region in an image by a collection of local feature-points and determine the object by the region with the maximum posterior probability of belonging to the object class. Based on the Bayes' theorem and Naive-Bayes assumptions, the posterior probability is reformulated as the sum of feature-scores. The feature-score is manifested in the form of the logarithm of a probability ratio. Instead of estimating the numerator and denominator probabilities separately, we readily employ the density ratio estimation techniques directly, and overcome the above limitation. Experiments on a car dataset and PASCAL VOC 2007 dataset validated the effectiveness of our method compared to the baselines. In addition, the performance can be further improved by taking advantage of the recently developed deep convolutional neural network features.

존 갈리아노 컬렉션의 디자인 특성에 관한 연구 - 크리스찬 디오르의 컬렉션을 중심으로 - (A Study about the Characteristics of Designs in John Galliano Collection - focusing on Christian Dior's Collection -)

  • 이귀영;조규화
    • 패션비즈니스
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    • 제13권2호
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    • pp.50-65
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    • 2009
  • The main purpose of this study is to identify characteristics of shapes of John Galliano's Dior Collection as the chief executive designer of Christian Dior Maison during $1996{\sim}2007$ after he showed himself in Paris in 1990. This study was based on the analyses of John Galliano's design trends of his collections, the pictures of his works in Christian Dior's collection, real works, documents and fashion magazines, newspapers, mass media, internet sites and other visual materials. The study identified characteristics of shapes in Dior Collection until 07/08 F/W as the chief executive designer of Christian Dior Maison, and the design trends before his post-Paris period. Followings are the conclusions of the study. First, Galliano was open to any types of cultures as a liberalist, and also respectful to the tradition or principles. He led the fashion business with new trends by exploring both sides. Second, he succeeded in commercializing his avant-garde feature. Especially, His creativity changed the image of Christian Dior to younger and more casual one. Third, born in England and worked in French, he always took both English (Victorian Style) and French(Napoleon era, Femme Fatal style) sides, and showed excellent formulation that the times needed by combining topical Chinese, Japanese, Egyptian styles.

기하학적 특징 모델을 이용한 강건한 영상 모자이크 기법 (Robust Image Mosaic using Geometrical Feature Model)

  • 김정훈;김대현;윤용인;최종수
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 추계종합학술대회 논문집(4)
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    • pp.13-16
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    • 2000
  • This paper presents a robust method to combine a collection of images with small fields of view to obtain an image with a large field of view. In the previous works, there are two main areas which one is a cross correlation-based method and the other is a feature-based method. The former is based on motion estimation from video sequences. so there are a problem on rotating a camera about optical axis. In the latter method, it is difficult to match correspondence feature points correctly.'re find correct correspondences, we proposed the geometrical feature model and correspondence filters and the Gaussian distribution weight function to blend the images smoothly. The experiments show that our method is robust and effective.

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침입탐지시스템에서의 특징 선택에 대한 연구 (A Study for Feature Selection in the Intrusion Detection System)

  • 한명묵
    • 융합보안논문지
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    • 제6권3호
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    • pp.87-95
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    • 2006
  • 침입은 컴퓨터 자원의 무결성, 기밀성, 유효성을 저해하고 컴퓨터 시스템의 보안정책을 파괴하는 일련의 행위의 집합이다. 이러한 침입을 탐지하는 침입탐지시스템은 데이터 수집, 데이터의 가공 및 축약, 침입 분석 및 탐지 그리고 보고 및 대응의 4 단계로 구성되어진다. 침입탐지시스템의 방대한 데이터가 수집된 후, 침입을 효율적으로 탐지하기 위해서는 특징 선택이 중요하다. 이 논문에서 유전자 알고리즘과 결정트리를 활용한 특징 선택 방법을 제안한다. 또한 KDD 데이터에서 실험을 통해 방법의 유효성을 검증한다.

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