• 제목/요약/키워드: Local feature

검색결과 932건 처리시간 0.031초

Revolutionizing Brain Tumor Segmentation in MRI with Dynamic Fusion of Handcrafted Features and Global Pathway-based Deep Learning

  • Faizan Ullah;Muhammad Nadeem;Mohammad Abrar
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제18권1호
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    • pp.105-125
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    • 2024
  • Gliomas are the most common malignant brain tumor and cause the most deaths. Manual brain tumor segmentation is expensive, time-consuming, error-prone, and dependent on the radiologist's expertise and experience. Manual brain tumor segmentation outcomes by different radiologists for the same patient may differ. Thus, more robust, and dependable methods are needed. Medical imaging researchers produced numerous semi-automatic and fully automatic brain tumor segmentation algorithms using ML pipelines and accurate (handcrafted feature-based, etc.) or data-driven strategies. Current methods use CNN or handmade features such symmetry analysis, alignment-based features analysis, or textural qualities. CNN approaches provide unsupervised features, while manual features model domain knowledge. Cascaded algorithms may outperform feature-based or data-driven like CNN methods. A revolutionary cascaded strategy is presented that intelligently supplies CNN with past information from handmade feature-based ML algorithms. Each patient receives manual ground truth and four MRI modalities (T1, T1c, T2, and FLAIR). Handcrafted characteristics and deep learning are used to segment brain tumors in a Global Convolutional Neural Network (GCNN). The proposed GCNN architecture with two parallel CNNs, CSPathways CNN (CSPCNN) and MRI Pathways CNN (MRIPCNN), segmented BraTS brain tumors with high accuracy. The proposed model achieved a Dice score of 87% higher than the state of the art. This research could improve brain tumor segmentation, helping clinicians diagnose and treat patients.

이동로봇주행을 위한 영상처리 기술

  • 허경식;김동수
    • 전자공학회지
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    • 제23권12호
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    • pp.115-125
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    • 1996
  • This paper presents a new algorithm for the self-localization of a mobile robot using one degree perspective Invariant(Cross Ratio). Most of conventional model-based self-localization methods have some problems that data structure building, map updating and matching processes are very complex. Use of a simple cross ratio can be effective to the above problems. The algorithm is based on two basic assumptions that the ground plane is flat and two locally parallel sloe-lines are available. Also it is assumed that an environmental map is available for matching between the scene and the model. To extract an accurate steering angle for a mobile robot, we take advantage of geometric features such as vanishing points. Feature points for cross ratio are extracted robustly using a vanishing point and intersection points between two locally parallel side-lines and vertical lines. Also the local position estimation problem has been treated when feature points exist less than 4points in the viewed scene. The robustness and feasibility of our algorithms have been demonstrated through real world experiments In Indoor environments using an indoor mobile robot, KASIRI-II(KAist Simple Roving Intelligence).

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도시홍수방재를 위한 수문모니터링시스템의 적용 (Application of Hydrological Monitoring System for Urban Flood Disaster Prevention)

  • 서규우;나현우;김남길
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2005년도 학술발표회 논문집
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    • pp.1209-1213
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    • 2005
  • It reflects well feature of slope that is characteristic of city river basin of Pusan local. Process various hydrological datas and basin details datas which is collected through basin basis data. weather satellite equipment(EMS-DEU) and automatic water level equipment(AWS-DEU) and use as basin input data of ILLUDAS model, SWMM model and HEC-HMS model In order to examine outflow feature of experiment basin and then use in reservoir design of experiment basin through calibration and verification about HEC-HMS model. Inserted design rainfall for 30 years that is design criteria of creek into HEC-HMS model and then calculated design floods according to change aspect of the impermeable rate. Capacity of reservoir was determined on the outflow mass curve. Designed imagination reservoir(volume $54,000m^3$) at last outlet upper stream of experiment basin, after designing reservoir. It could be confirmed that the peak flow was reduced resulting from examining outflow aspect. Designing reservoir must decrease outflow of urban areas.

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패턴 인식을 위한 유전 알고리즘의 개관 (Review on Genetic Algorithms for Pattern Recognition)

  • 오일석
    • 한국콘텐츠학회논문지
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    • 제7권1호
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    • pp.58-64
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    • 2007
  • 패턴 인식 분야에는 지수적 탐색 공간을 가진 최적화 문제가 많이 있다. 이를 해결하기 위해 부 최적해를 구하는 순차 탐색 알고리즘이 사용되어 왔고, 이들 알고리즘은 국부 최적점에 빠지는 문제점을 안고 있다. 최근 이를 극복하기 위해 유전 알고리즘을 사용하는 사례가 많아졌다. 이 논문은 특징 선택, 분류기 앙상블 선택, 신경망 가지치기, 군집화 문제의 지수적 탐색 공간 특성을 설명하고 이를 해결하기 위한 유전 알고리즘을 살펴본다. 또한 향후 연구로서 가치가 높은 주제들에 대해 소개한다.

영상 교시기반 주행 알고리듬 성능 평가 (Performance Evaluation of Visual Path Following Algorithm)

  • 최이삭;하종은
    • 제어로봇시스템학회논문지
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    • 제17권9호
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    • pp.902-907
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    • 2011
  • In this paper, we deal with performance evaluation of visual path following using 2D and 3D information. Visual path follow first teaches driving path by selecting milestone images then follows the same route by comparing the milestone image and current image. We follow the visual path following algorithm of [8] and [10]. In [8], a robot navigated with 2D image information only. But in [10], local 3D geometries are reconstructed between the milestone images in order to achieve fast feature prediction which allows the recovery from tracking failures. Experimental results including diverse indoor cases show performance of each algorithm.

Sparse Representation based Two-dimensional Bar Code Image Super-resolution

  • Shen, Yiling;Liu, Ningzhong;Sun, Han
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권4호
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    • pp.2109-2123
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    • 2017
  • This paper presents a super-resolution reconstruction method based on sparse representation for two-dimensional bar code images. Considering the features of two-dimensional bar code images, Kirsch and LBP (local binary pattern) operators are used to extract the edge gradient and texture features. Feature extraction is constituted based on these two features and additional two second-order derivatives. By joint dictionary learning of the low-resolution and high-resolution image patch pairs, the sparse representation of corresponding patches is the same. In addition, the global constraint is exerted on the initial estimation of high-resolution image which makes the reconstructed result closer to the real one. The experimental results demonstrate the effectiveness of the proposed algorithm for two-dimensional bar code images by comparing with other reconstruction algorithms.

Image Feature Detection and Contrast Enhancement Algorithms Based on Statistical Tests

  • Kim, Yeong-Hwa;Nam, Ji-Ho
    • Journal of the Korean Data and Information Science Society
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    • 제18권2호
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    • pp.385-399
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    • 2007
  • In many image processing applications, a random noise makes some trouble since most video enhancement functions produce visual artifacts if a priori of the noise is incorrect. The basic difficulty is that the noise and the signal are difficult to be distinguished. Typical unsharp masking (UM) enhances the visual appearances of images, but it also amplifies the noise components of the image. Hence, the applications of a UM are limited when noises are presented. This paper proposed statistical algorithms based on parametric and nonparametric tests to adaptively enhance the image feature and the noise combining while applying UM. With the proposed algorithm, it is made possible to enhance the local contrast of an image without amplifying the noise.

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LPCA에 기반한 GMM을 이용한 화자 식별 (Speaker Identification Using GMM Based on LPCA)

  • 서창우;이윤정;이기용
    • 음성과학
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    • 제12권2호
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    • pp.171-182
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    • 2005
  • An efficient GMM (Gaussian mixture modeling) method based on LPCA (local principal component analysis) with VQ (vector quantization) for speaker identification is proposed. To reduce the dimension and correlation of the feature vector, this paper proposes a speaker identification method based on principal component analysis. The proposed method firstly partitions the data space into several disjoint regions by VQ, and then performs PCA in each region. Finally, the GMM for the speaker is obtained from the transformed feature vectors in each region. Compared to the conventional GMM method with diagonal covariance matrix, the proposed method requires less storage and complexity while maintaining the same performance requires less storage and shows faster results.

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The southeastern region of the Vela SNR

  • Kim, Il-Joong;Seon, Kwang-Il;Min, Kyoung-Wook
    • 천문학회보
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    • 제35권2호
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    • pp.69.2-69.2
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    • 2010
  • We investigate the southeastern region of the Vela supernova remnant (SNR) in the multi-wavelength domains. This region is quite interesting because it includes the bullet feature D/D´ and another SNR (the Vela Jr.). The C IV $\lambda\lambda1548$, 1551 emission-line morphologies obtained from the FIMS/SPEAR data show that there are several local peaks of C IV on the bullet D/D´ and the Vela Jr. SNR. This may provide clues to direct interaction between both SNRs. Also, we found that the southeastern side of the Vela is in direct contact with an H-alpha ring feature whose central source seems to be a B-type star, HD 76161. The C IV emission peaks along this contact boundary. We investigate this interacting region in detail.

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압축영역에서 객체 움직임 맵에 의한 효율적인 비디오 인덱싱 방법에 관한 연구 (An Efficient Video Indexing Method using Object Motion Map in compresed Domain)

  • 김소연;노용만
    • 한국정보처리학회논문지
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    • 제7권5호
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    • pp.1570-1578
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    • 2000
  • Object motion is an important feature of content in video sequences. By now, various methods to exact feature about the object motion have been reported[1,2]. However they are not suitable to index video using the motion, since a lot of bits and complex indexing parameters are needed for the indexing [3,4] In this paper, we propose object motion map which could provide efficient indexing method for object motion. The proposed object motion map has both global and local motion information during an object is moving. Furthermore, it requires small bit of memory for the indexing. to evaluate performance of proposed indexing technique, experiments are performed with video database consisting of MPEG-1 video sequence in MPEG-7 test set.

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