• 제목/요약/키워드: descriptors

검색결과 505건 처리시간 0.024초

실루엣 영상기반 보행 분석을 위한 형태 기술자의 성능 평가 (Performance Evaluation of Shape Descriptors for Gait Analysis Based on Silhouette Sequence)

  • 김선종
    • 지능정보연구
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    • 제15권4호
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    • pp.53-64
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    • 2009
  • 본 논문에서는 실루엣 동영상으로부터 보행 분석에 사용되는 형태 기술자의 성능을 평가하였다. 형태 기술자는 모멘트기술자(MD), 푸리에기술자(FD), 저나이크기술자(ZD)를 사용하였다. 먼저 성능 평가 지수인 비대칭 지수 AI와 주기지수 PI를 정의하였다. 이 지수는 보행은 주기적으로 주어지며, 이를 표현한 형태 기술자도 같은 보행 주기를 가져야 하는 것을 기반으로 한다. 또한 지수는 형태의 특성을 정확하게 나타내는 인식 성능보다는 형태 기술자들에 의해 얼마나 잘 표현되었는가를 평가하는 것이다, 성능평가결과, ZD가AI = 1.09, PI = 2.21로 대체로 무난한 성능으로 나타났으며, FD가 MD보다 AI = 0.93로 하나의 주기내에서의 성능이 우수하였다. 반면 MD는 FD보다 PI = 2.37로 반복적인 특징이 높게 나타났다. 또한 형태 기술자는 5~10개 정도의 파라미터 개수를 사용하는 것이 좋은 성능을 가짐을 보였다.

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과학기술용어(科學技術用語) 시소러스 대역(對譯) 데이터베이스 구축(構築) (A Study on Multi-Lingual Thesaurus Database Construction of Scientific and Technical Terms)

  • 김은식
    • 정보관리연구
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    • 제22권2호
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    • pp.1-28
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    • 1991
  • 본(本) 연구(硏究)는 한글 과학기술용어(科學技術用語)의 표준화(標準化)를 위한 기초자료를 마련하여 국내(國內) 과학기술(科學技術) 데이터베이스의 제작을 촉진하고, 또한 한글 전문용어(專門用語)와 이에 대응하는 영어(英語) 용어(用語) 및 일어(日語) 용어(用語)를 안내해 줌으로써 해외(海外) 데이터베이스 검색시(檢索時)에 편리한 검색(檢索) 툴로서 활용하는 데 목적(目的)이 있다. 과학기술분야(科學技術分野)에서 사용되고 있는 전문용어(專門用語)의 한글 용어, 영어(英語) 용어, 일어(日語) 용어 시소러스에 대한 대역(對譯) 데이터베이스를 구축한 것이다. 시소러스의 이론적인 배경을 고찰하였으며, 과학기술분야(科學技術分野) 전문용어(專門用語)의 수집은 일본과학기술정보(日本科學技術情報)센터가 1987년에 발행한 $\ulcorner$과학기술용어(科學技術用語) 시소러스 영일(英日) 리스트$\lrcorner$$\ulcorner$과학기술용어(科學技術用語) 시소러스 일영(日英) 리스트$\lrcorner$를 근거자료로 하여 일어(日語) 용어(用語) 및 영어(英語) 용어(用語)에 1 대(對) 1로 대응하는 한글 용어로 번역(飜譯)하였다. 과학기술용어(科學技術用語) 시소러스 대역(對譯) 데이터베이스에 수록된 한글 디스크립터는 38,318 용어, 한글 비디스크립터는 2,870용어, 영어(英語) 디스크립터는 38,318 용어, 영어(英語) 비디스크립터는 11,910 용어, 일어(日語) 디스크립터는 38,318 용어, 일어(日語) 디스크립터는 9,789 용어이다.

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MPEG-7 기술자를 이용한 알파벳 인식 (Alphabet Recognition by Using MPEG-7 Descriptors)

  • 진성호;강호경;정광서;노용만
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(3)
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    • pp.137-140
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    • 2001
  • This paper has been studied for alphabet recognition by using MPEG-7 descriptors. As an application of MPEG-7, the algorithms in this paper have employed Homogeneous Texture descriptor and Edge Histogram descriptor. For confident matching a voting system is used with a tree structure,

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ATM 기반의 VBR 비디오 서비스를 위한 트래픽 기술자 Dimensioning에 관한 연구 (A Study on Dimensioning of Traffic Descriptors for VBR Video Sources on ATM Networks)

  • 유상조;홍성훈;김성대
    • 한국통신학회논문지
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    • 제24권7B호
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    • pp.1268-1278
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    • 1999
  • 본 논문에서는 ATM 망에서 VBR MPEG 비디오 트래픽에 대한 리키버킷 기반의 UPC 제어 시 적절한 트래픽 기술자 조합을 선정할 수 있는 해석적 방법을 제안한다. 장면기반 비디오 트래픽 모델링을 통해 UPC에서의 셀 위반확률을 해석적으로 유도하고, 이를 이용하여 원하는 UPC 제어 위반확률을 갖는 트래픽 기술자의 조합을 선정할 수 있음을 보인다. 실험 대상 MPEG 비디오 시퀀스에 대해 본 논문에서 제안한 해석적 트래픽 기술자 dimensioning 결과가 실제 시뮬레이션에 의한 선정결과를 잘 근사화 함을 모의실험을 통해 보인다. 마지막으로 망에서 호 수락제어로 ON/OFF 소스의 등가대역폭을 이용할 경우, 가능한 트래픽 기술자 조합에 대해 할당되는 등가대역폭을 분석하여 효율적인 트래픽 기술자 선정방안을 제안한다.

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Evaluation of Histograms Local Features and Dimensionality Reduction for 3D Face Verification

  • Ammar, Chouchane;Mebarka, Belahcene;Abdelmalik, Ouamane;Salah, Bourennane
    • Journal of Information Processing Systems
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    • 제12권3호
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    • pp.468-488
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    • 2016
  • The paper proposes a novel framework for 3D face verification using dimensionality reduction based on highly distinctive local features in the presence of illumination and expression variations. The histograms of efficient local descriptors are used to represent distinctively the facial images. For this purpose, different local descriptors are evaluated, Local Binary Patterns (LBP), Three-Patch Local Binary Patterns (TPLBP), Four-Patch Local Binary Patterns (FPLBP), Binarized Statistical Image Features (BSIF) and Local Phase Quantization (LPQ). Furthermore, experiments on the combinations of the four local descriptors at feature level using simply histograms concatenation are provided. The performance of the proposed approach is evaluated with different dimensionality reduction algorithms: Principal Component Analysis (PCA), Orthogonal Locality Preserving Projection (OLPP) and the combined PCA+EFM (Enhanced Fisher linear discriminate Model). Finally, multi-class Support Vector Machine (SVM) is used as a classifier to carry out the verification between imposters and customers. The proposed method has been tested on CASIA-3D face database and the experimental results show that our method achieves a high verification performance.

Three-Dimensional Shape Recognition and Classification Using Local Features of Model Views and Sparse Representation of Shape Descriptors

  • Kanaan, Hussein;Behrad, Alireza
    • Journal of Information Processing Systems
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    • 제16권2호
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    • pp.343-359
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    • 2020
  • In this paper, a new algorithm is proposed for three-dimensional (3D) shape recognition using local features of model views and its sparse representation. The algorithm starts with the normalization of 3D models and the extraction of 2D views from uniformly distributed viewpoints. Consequently, the 2D views are stacked over each other to from view cubes. The algorithm employs the descriptors of 3D local features in the view cubes after applying Gabor filters in various directions as the initial features for 3D shape recognition. In the training stage, we store some 3D local features to build the prototype dictionary of local features. To extract an intermediate feature vector, we measure the similarity between the local descriptors of a shape model and the local features of the prototype dictionary. We represent the intermediate feature vectors of 3D models in the sparse domain to obtain the final descriptors of the models. Finally, support vector machine classifiers are used to recognize the 3D models. Experimental results using the Princeton Shape Benchmark database showed the average recognition rate of 89.7% using 20 views. We compared the proposed approach with state-of-the-art approaches and the results showed the effectiveness of the proposed algorithm.

Digital Video Steganalysis Based on a Spatial Temporal Detector

  • Su, Yuting;Yu, Fan;Zhang, Chengqian
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권1호
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    • pp.360-373
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    • 2017
  • This paper presents a novel digital video steganalysis scheme against the spatial domain video steganography technology based on a spatial temporal detector (ST_D) that considers both spatial and temporal redundancies of the video sequences simultaneously. Three descriptors are constructed on XY, XT and YT planes respectively to depict the spatial and temporal relationship between the current pixel and its adjacent pixels. Considering the impact of local motion intensity and texture complexity on the histogram distribution of three descriptors, each frame is segmented into non-overlapped blocks that are $8{\times}8$ in size for motion and texture analysis. Subsequently, texture and motion factors are introduced to provide reasonable weights for histograms of the three descriptors of each block. After further weighted modulation, the statistics of the histograms of the three descriptors are concatenated into a single value to build the global description of ST_D. The experimental results demonstrate the great advantage of our features relative to those of the rich model (RM), the subtractive pixel adjacency model (SPAM) and subtractive prediction error adjacency matrix (SPEAM), especially for compressed videos, which constitute most Internet videos.

LAG TIME RELATIONS TO CATCHMENT SHAPE DESCRIPTORS AND HYDROLOGICAL RESPONSE

  • Kim, Joo-Cheol;Kim, Jae-Han
    • Water Engineering Research
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    • 제6권2호
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    • pp.91-99
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    • 2005
  • One of the most important factors for estimating a flood runoff from streams is the lag time. It is well known that the lag time is affected by the morphometric properties of basin which can be expressed by catchment shape descriptors. In this paper, the notion of the geometric characteristics of an equivalent ellipse proposed by Moussa(2003) was applied for calculating the lag time of geomorphologic instantaneous unit hydrograph(GIUH) at a basin outlet. The lag time was obtained from the observed data of rainfall and runoff by using the method of moments and the procedure based on geomorphology was used for GIUH. The relationships between the basin morphometric properties and the hydrological response were discussed based on application to 3 catchments in Korea. Additionally, the shapes of equivalent ellipse were examined how they are transformed from upstream area to downstream one. As a result, the relationship between the lag time and descriptors was shown to be close, and the shape of ellipse was presented to approach a circle along the river downwards. These results may be expanded to the estimation of hydrological response of ungauged catchment.

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Genetic Diversity of Soybean Pod Shape Based on Elliptic Fourier Descriptors

  • Truong Ngon T.;Gwag Jae-Gyun;Park Yong-Jin;Lee Suk-Ha
    • 한국작물학회지
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    • 제50권1호
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    • pp.60-66
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    • 2005
  • Pod shape of twenty soybean (Glycine max L. Merrill) genotypes was evaluated quantitatively by image analysis using elliptic Fourier descriptors and their principal components. The closed contour of each pod projection was extracted, and 80 elliptic Fourier coefficients were calculated for each contour. The Fourier coefficients were standardized so that they were invariant of size, rotation, shift, and chain code starting point. Then, the principal components on the standardized Fourier coefficients were evaluated. The cumulative contribution at the fifth principal component was higher than $95\%$, indicating that the first, second, third, fourth, and fifth principal components represented the aspect ratio of the pod, the location of the pod centroid, the sharpness of the two pod tips and the roundness of the base in the pod contour, respectively. Analysis of variance revealed significant genotypic differences in these principal components and seed number per pod. As the principal components for pod shape varied continuously, pod shape might be controlled by polygenes. It was concluded that principal component scores based on elliptic Fourier descriptors yield seemed to be useful in quantitative parameters not only for evaluating soybean pod shape in a soybean breeding program but also for describing pod shape for evaluating soybean germplasm.

우리나라 중소하천 코리도의 자연성 평가기법 연구 (A Study on Evaluation Method of Stream Naturalness for Ecological Restoration of Stream Corridors)

  • 조용현
    • 한국조경학회지
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    • 제25권2호
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    • pp.73-81
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    • 1997
  • The main purpose of this study was to develop a new method for evaluation of stream naturalness in order to appraise and prescribe for streams effectively in the process of ecological restoration of stream corridors. The results are as follows : 1) For this purpose six factors were selected on considering the spatial axes of stream corridor variation and total 20 descriptors about the physical structure were selected. 2) The calculation of S.N.I. for each segment was consisted of three steps, such as calculation of S.N.I.s of the individual descriptors, averaging all the descriptors's for each factor, and finally averaging the factors's for the Total S.N.I. 3) The evaluation unit was decided to be 100m size. The score system ranging 1~5 was adopted. Weighting parameters of factors were unified with each other. 4) A GIS model was adopted for classification, calculation, querying, analysing, and presenting S.N.I. information. And the format of S.N.I. maps including statistical graphs and other spatial watershed information was designed for the GIS odel. The naturalness of stream corridor was was investigated by the naturalness of habitat, and assessed by the descriptors focused on physical structure, therefore the S.N.I. can manifest prescriptions for restoration of the stream corridor. On the other hand because some evaluation factors such as water quality, water volume, fauna, flora, functions of stream exosystem has been excluded, S.N.I. could have some limits on representing the full aspects of stream naturalness. This evaluation method is hypothetical one, so it would be investigated through iterative applicatons.

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