• Title/Summary/Keyword: Local Maxima

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Image Mosaics using Morphological Corner Detection (모폴로지 코너 검출법을 이용한 영상 모자이크)

  • 조세연;이정호;유형승;조아영;정동석
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.04b
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    • pp.700-702
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    • 2004
  • 모자이크는 설러 장의 영상을 하나의 큰 영상으로 만드는 것을 말한다. 본 논문은 asymmetrical closing이라고 불리는 모폴로지에 의한 closing operator를 사용한 영상 모자이크에 관한 연구이다. asymmetrical closing을 하기 위한 structuring element를 소개하고 이것을 이용한 코너 정 추출 방법 및 local maxima에 대해서도 소개한다. 여러 개의 코너 정들 중 조건을 만족하는 tie point들을 이용하여 Perspective 변환 파라미터를 추출하여 최종 모자이크 결과 영상을 생성하게 된다.

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Isolation and Characterization of a Mesophilic Arthrospira maxima Strain Capable of Producing Docosahexaenoic Acid

  • Hu, Hongjun;Li, Yeguang;Yin, Chuntao;Ouyang, Yexin
    • Journal of Microbiology and Biotechnology
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    • v.21 no.7
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    • pp.697-702
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    • 2011
  • A strain of the cyanobacterium Arthrospira was isolated from Lake Chahannaoer in northern China and was characterized according to microscopic morphology, photosynthetic oxygen-evolving activity, growth rate, and nutritional profile. Compared with thermophilic Arthrospira species occurring naturally in tropical and subtropical lakes, this isolate is mesophilic and grows optimally at ${\sim}20^{\circ}C$. The total protein, fatty acid, phycocyanin, carotenoid, and chlorophyll a contents were 67.6, 6.1, 4.32, 0.29, and 0.76 grams per 100 grams of dry weight, respectively. The strain is rich in polyunsaturated fatty acids (PUFAs). An essential omega-3 fatty acid, docosahexaenoic acid (DHA), was detected, and ${\gamma}$-linolenic acid (GLA) and DHA accounted for 28.3% of the total fatty acid content. These features of this newly isolated strain make it potentially useful in commercial mass culture in local areas or as a biofuel feedstock. It is also an alternative resource for studying the metabolic PUFA pathways and mechanisms of cold stress tolerance in cyanobacteria.

Design and Implementation of the Security System for the Moving Object Detection (이동물체 검출을 위한 보안 시스템의 설계 및 구현)

  • 안용학;안일영
    • Convergence Security Journal
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    • v.2 no.1
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    • pp.77-86
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    • 2002
  • In this paper, we propose a segmentation algorithm that can reliably separate moving objects from noisy background in the image sequence received from a camera at the fixed position. Image segmentation is one of the most difficult process in image processing and an adoption in the change of environment must be considered for the increase in the accuracy of the image. The proposed algorithm consists of four process : generation of the difference image between the input image and the reference image, removes the background noise using the background nois modeling to a difference image histogram, then selects the candidate initial region using local maxima to the difference image, and gradually expanding the connected regions, region by region, using the shape information. The test results show that the proposed algorithm can detect moving objects like intruders very effectively in the noisy environment.

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A Method to Detect Multiple Plane Areas by using the Iterative Randomized Hough Transform(IRHT) and the Plane Detection (평면 추출셀과 반복적 랜덤하프변환을 이용한 다중 평면영역 분할 방법)

  • Lim, Sung-Jo;Kim, Dae-Gwang;Kang, Dong-Joong
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.11
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    • pp.2086-2094
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    • 2008
  • Finding a planar surface on 3D space is very important for efficient and safe operation of a mobile robot. In this paper, we propose a method using a plane detection cell (PDC) and iterative randomized Hough transform (IRHT) for finding the planar region from a 3D range image. First, the local planar region is detected by a PDC from the target area of the range image. Each plane is then segmented by analyzing the accumulated peaks from voting the local direction and position information of the local PDC in Hough space to reduce effect of noises and outliers and improve the efficiency of the HT. When segmenting each plane region, the IRHT repeatedly decreases the size of the planar region used for voting in the Hough parameter space in order to reduce the effect of noise and solve the local maxima problem in the parameter space. In general, range images have many planes of different normal directions. Hence, we first detected the largest plane region and then the remained region is again processed. Through this procedure, we can segment all planar regions of interest in the range image.

Automatic partial shape recognition system using adaptive resonance theory (적응공명이론에 의한 자동 부분형상 인식시스템)

  • 박영태;양진성
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.3
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    • pp.79-87
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    • 1996
  • A new method for recognizing and locating partially occluded or overlapped two-dimensional objects regardless of their size, translation, and rotation, is presented. Dominant points approximating occuluding contoures of objects are generated by finding local maxima of smoothed k-cosine function, and then used to guide the contour segment matching procedure. Primitives between the dominant points are produced by projecting the local contours onto the line between the dominant points. Robust classification of primitives. Which is crucial for reliable partial shape matching, is performed using adaptive resonance theory (ART2). The matched primitives having similar scale factors and rotation angles are detected in the hough space to identify the presence of the given model in the object scene. Finally the translation vector is estimated by minimizing the mean squred error of the matched contur segment pairs. This model-based matching algorithm may be used in diveerse factory automation applications since models can be added or changed simply by training ART2 adaptively without modifying the matching algorithm.

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A Time-Domain Parameter Extraction Method for Speech Recognition using the Local Peak-to-Peak Interval Information (국소 극대-극소점 간의 간격정보를 이용한 시간영역에서의 음성인식을 위한 파라미터 추출 방법)

  • 임재열;김형일;안수길
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.2
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    • pp.28-34
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    • 1994
  • In this paper, a new time-domain parameter extraction method for speech recognition is proposed. The suggested emthod is based on the fact that the local peak-to-peak interval, i.e., the interval between maxima and minima of speech waveform is closely related to the frequency component of the speech signal. The parameterization is achieved by a sort of filter bank technique in the time domain. To test the proposed parameter extraction emthod, an isolated word recognizer based on Vector Quantization and Hidden Markov Model was constructed. As a test material, 22 words spoken by ten males were used and the recognition rate of 92.9% was obtained. This result leads to the conclusion that the new parameter extraction method can be used for speech recognition system. Since the proposed method is processed in the time domain, the real-time parameter extraction can be implemented in the class of personal computer equipped onlu with an A/D converter without any DSP board.

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TIME EVOLUTION OF SCOUR AROUND BRIDGE ABUTMENTS

  • Francesco Ballio;Enrico Orsi
    • Water Engineering Research
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    • v.2 no.4
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    • pp.243-259
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    • 2001
  • Local phenomena around bridge piers and abutments are generally considered to be similar, nevertheless the presence of the incoming boundary layer on the side wall in the abutment case generates extra pressure gradients and consequently a more complex vortex pattern. In the literature, experimental data for bridge abutments are relatively scarce; in particular almost no data are available for the time evolution of the scour. In this work we present the results of several long duration (3 days longrightarrow5weeks) clear water scour laboratory tests around bridge abutments; the time evolution of the erosion process is analysed with respect to local and global characteristic values (maxima, volume, hole shape). In particular we analyse the effect of the constriction ratio b/B between the transversal obstacle dimension and the flume width: in many practical situations abutments (or piers) obstruct a significant portion of the channel, so that the average acceleration due to constriction is expected to increase the scour effects of the local acceleration around the obstacle. Measured values for maximum scour are poorly predicted by literature formulas. Scour depths are positively correlated with the constriction ratio, but increases are smaller than expected from literature indications. Experimental results show that models for bridge piers cannot be directly applied to abutments; in particular, time scales for the latter are significantly larger than for piers.

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Reducing Computational Complexity for Local Maxima Detection Using Facet Model (페이싯 모델을 이용한 국부 극대점 검출의 처리 속도 개선)

  • Lee, Gyoon-Jung;Park, Ji-Hwan;Joo, Jae-Heum;Nam, Ki-Gon
    • Journal of the Institute of Convergence Signal Processing
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    • v.13 no.3
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    • pp.130-135
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    • 2012
  • In this paper, we propose a technique to detect the size and location of the small target in images by using Gaussian kernel repeatedly. In order to detect the size and location of the small target, we find the local maximum value by applying the facet model and then use the $3{\times}3$ Gaussian kernel repeatedly. we determine the size of small target by comparing the local maximum value $D_2$ according to the number of iteration. To reduce the computational complexity, we use the Gaussian pyramid when using the kernel repeatedly. Through the experiment, we verified that the size and location of the small target is detected by the number of iterations and results show improvements from conventional methods.

Image Segmentation Using Mathematical Morphology (수리형태학을 이용한 영상 분할)

  • Cho Sun-gil;Kang Hyunchul
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.11C
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    • pp.1076-1082
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    • 2005
  • Recently, there have been much efforts in the image segmentation using morphological approach. Among them, the watershed algorithm is one of powerful tools which can take advantages of both of the conventional edge-based segmentation and region-based segmentation. The concept of watershed is based on topographic analogy. But, its high sensitivity to noise yields a very large number of resulting segmented regions which leads to oversegmentation. So we suggest the restricted waterfall algorithm which reduce the oversegmentation by eliminate not only local minima but also local maxima. As a result, the restricted waterfall algorithm has a good segmented image than the other methods, and has a better binary image than the histogram thresholding method.

House Rent Control System and Its Implementation in France (프랑스 주택 임대료 규제 및 관련 제도 연구)

  • Lee, Seong-Keun;Choi, Min-Ah
    • Land and Housing Review
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    • v.9 no.4
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    • pp.1-9
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    • 2018
  • Since year 2000, French housing and rent prices rose at a rapid rate and the housing market has been overheated. Face to this phenomena, the French government enacted a new law Alur which is a legislatif tool to control the private housing rent price for the cities, where the tension of the housing market is very high. This new law has impacted the housing market in two major ways. First, for the 38 cities designated by this law, the rent price's increase rate can not rise above the IRL, which is the rent reference index. Secondly, this law also permits local authorities to control the housing rent's price following the concrete price guidance. Especially in Paris, the city applicated this method for private rental housing since 2015. This city classified its own area by 14 zones. Based on the market surveys of each sector, local authority made a guidance for private housing rent's price. The guideline is consisted of average prices, maxima and minima price by types, which is classified by the construction year, number of rooms and furnished or not. Therefore, this study aims to understand french housing rent's price control system and draw implementation for korean housing rent policies. This research is meaningful for it introduces recent foreign regislations which could be helpful to control the housing market in Korea.