• Title/Summary/Keyword: Visual analysis

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Background Subtraction Algorithm Based on Multiple Interval Pixel Sampling (다중 구간 샘플링에 기반한 배경제거 알고리즘)

  • Lee, Dongeun;Choi, Young Kyu
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.1
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    • pp.27-34
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    • 2013
  • Background subtraction is one of the key techniques for automatic video content analysis, especially in the tasks of visual detection and tracking of moving object. In this paper, we present a new sample-based technique for background extraction that provides background image as well as background model. To handle both high-frequency and low-frequency events at the same time, multiple interval background models are adopted. The main innovation concerns the use of a confidence factor to select the best model from the multiple interval background models. To our knowledge, it is the first time that a confidence factor is used for merging several background models in the field of background extraction. Experimental results revealed that our approach based on multiple interval sampling works well in complicated situations containing various speed moving objects with environmental changes.

Latent Semantic Indexing Analysis of K-Means Document Clustering for Changing Index Terms Weighting (색인어 가중치 부여 방법에 따른 K-Means 문서 클러스터링의 LSI 분석)

  • Oh, Hyung-Jin;Go, Ji-Hyun;An, Dong-Un;Park, Soon-Chul
    • The KIPS Transactions:PartB
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    • v.10B no.7
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    • pp.735-742
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    • 2003
  • In the information retrieval system, document clustering technique is to provide user convenience and visual effects by rearranging documents according to the specific topics from the retrieved ones. In this paper, we clustered documents using K-Means algorithm and present the effect of index terms weighting scheme on the document clustering. To verify the experiment, we applied Latent Semantic Indexing approach to illustrate the clustering results and analyzed the clustering results in 2-dimensional space. Experimental results showed that in case of applying local weighting, global weighting and normalization factor, the density of clustering is higher than those of similar or same weighting schemes in 2-dimensional space. Especially, the logarithm of local and global weighting is noticeable.

Robust Method of Video Contrast Enhancement for Sudden Illumination Changes (급격한 조명 변화에 강건한 동영상 대조비 개선 방법)

  • Park, Jin Wook;Moon, Young Shik
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.11
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    • pp.55-65
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    • 2015
  • Contrast enhancement methods for a single image applied to videos may cause flickering artifacts because these methods do not consider continuity of videos. On the other hands, methods considering the continuity of videos can reduce flickering artifacts but it may cause unnecessary fade-in/out artifacts when the intensity of videos changes abruptly. In this paper, we propose a robust method of video contrast enhancement for sudden illumination changes. The proposed method enhances each frame by Fast Gray-Level Grouping(FGLG) and considers the continuity of videos by an exponential smoothing filter. The proposed method calculates the smoothing factor of an exponential smoothing filter using a sigmoid function and applies to each frame to reduce unnecessary fade-in/out effects. In the experiment, 6 measurements are used for the performance analysis of the proposed method and traditional methods. Through the experiment. it has been shown that the proposed method demonstrates the best quantitative performance of MSSIM and Flickering score and show the adaptive enhancement under sudden illumination change through the visual quality comparison.

Landslide Detection and Landslide Susceptibility Mapping using Aerial Photos and Artificial Neural Networks (항공사진을 이용한 산사태 탐지 및 인공신경망을 이용한 산사태 취약성 분석)

  • Oh, Hyun-Joo
    • Korean Journal of Remote Sensing
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    • v.26 no.1
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    • pp.47-57
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    • 2010
  • The aim of this study is to detect landslide using digital aerial photography and apply the landslide to landslide susceptibility mapping by artificial neural network (ANN) and geographic information system (GIS) at Jinbu area where many landslides have occurred in 2006 by typhoon Ewiniar, Bilis and Kaemi. Landslide locations were identified by visual interpretation of aerial photography taken before and after landslide occurrence, and checked in field. For landslide susceptibility mapping, maps of the topography, geology, soil, forest, lineament, and landuse were constructed from the spatial data sets. Using the factors and landslide location and artificial neural network, the relative weight for the each factors was determinated by back-propagation algorithm. As the result, the aspect and slope factor showed higher weight in 1.2-1.5 times than other factors. Then, landslide susceptibility map was drawn using the weights and finally, the map was validated by comparing with landslide locations that were not used directly in the analysis. As the validation result, the prediction accuracy showed 81.44%.

Women's Image and Fashion Expressed in Popular Park Hyewon Weekly Magazine 'Sunday-Seoul' -From First Issue, 1968 to 168 Issue, 1971- (통속 주간지 『선데이 서울』 화보와 기사에 나타난 여성이미지와 패션 -1968년 창간호부터 1971년 168호까지-)

  • Park, Hyewon
    • Journal of Fashion Business
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    • v.23 no.5
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    • pp.31-47
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    • 2019
  • This study focuses on women and fashion in Korea between the 1960s and 1970s, when the government regulated the socio-cultural aspects of individuals while achieving remarkable economic industrialization, particularly through the representative popular weekly magazine 'Sunday-Seoul'. The scope of this study included 168 issues from September 22, 1968 to December 26, 1971. Two research methods were applied, literature research and content analysis research. First, the literature on Korean society, culture, women's fashion, the sociological, feminine and popular cultural studies were reviewed. Thereafter, the contents, cover, articles, pictorials were collected and analyzed for classification and identification of the women's images and women's fashion. In the case of fashion articles, the contents of vocabulary and description texts were highlighted, and in the case of pictorials, the visual elements such as images, silhouettes of clothes, details of features, and patterns of materials were assessed. The images of women in Sunday Seoul's articles and pictorials exhibited extreme opposite, presenting the most important purpose of marriage, 'wise mother and good wife' and 'image of sexual object' for men. The two images of women differed; however, there was one more female image 'industrial laborer' which was placed in the blind spot of interest. The characteristics of fashion which appeared in 'Sunday-Seoul' were 'uniform modern elegance' based on neat mini-style, and 'sexual image of exposure fashion' which endeavored to selectively borrow from overseas pictorials and trend-oriented articles. This could be viewed as a 'transformation of traditional Hanbok', 'avant-garde trend' and 'de-sexualization & indifference of fashion'.

A study on the analysis of groundwater falling by subsurface dam (지하댐 건설로 인한 주변부 지하수위 하강 분석 연구)

  • Oh, Jun Oh;Young, Jeon Ju;Park, Jae Hyeon;Jun, Sang Mi
    • Proceedings of the Korea Water Resources Association Conference
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    • 2017.05a
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    • pp.117-117
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    • 2017
  • 울산시는 반구대 암각화 보존과 시민들을 위한 청정원수 공급과의 갈등을 지난 20년간 논의해 왔다. 이는 반구대 암각화 보존을 위하여 사연댐 수위를 낮추어 관리하여 발생하는 12.0만$m^3$의 용수부족량분과 장래 용수부족량분 30.0만$m^3$에 대하여 낙동강원수를 사용하여야 하는데 사연댐에 비해 수질이 나쁜 낙동강 원수사용의 비율이 높아지면 정수비용 증가로 인한 시민의 부담이 증가한다는 울산시의 입장과 반구대 암각화 보존을 위하여 사연댐의 수위를 낮추어 관리해야 한다는 문화재청의 입장으로 마찰을 빚어왔다. 이에 울산시의 신규 수자원 개발의 필요성이 대두되었고 그 방안으로 지하댐건설이 하나의 대안으로 제시되었다. 이에 본 연구에서는 울산시 울주군 사연리 주변에 지하댐이 건설된다면 그 주변 지하수위 변화에 대하여 지하수 모델(Visual-MODFLOW)를 사용하여 분석하였다. 먼저 울산시 울주군 사연리 인근에 지하댐을 건설한다면 일 30.0만$m^3$의 취수가 가능한지에 대한 여부를 분석하였으며, 가능하다면 용수취수로 인한 주변부 지하수위 하강이 어떻게 발생하는지에 대하여 분석하였다. 그 결과 일 30.0만$m^3$의 용수취수가 가능한 것으로 분석되었으며, 그로 인한 지하수위 하강은 취수정이 설치된 지점에서는 최대 1.8m의 지하수위 하강이 발생하며, 그 영향반경은 약 50.0m인 것으로 분석되었다. 또한 지하수위 하강이 약 0.3m ~ 1.8m까지 발생하는데 그 반경은 최대 약 700.0m 인 것으로 분석되었다. 본 연구 결과를 바탕으로 울산시 신규 수자원 개발을 위하여 지하댐을 건설이 가능할 것으로 판단되며 만약 울산시 신규 수자원으로 지하댐을 건설한다면 추가 정밀조사를 통하여 정확한 지하수위 변동 특성을 분석해야 할 것으로 판단된다.

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Analysis of the variation characteristics of the surrounding groundwater level to the weir management level (The Nakdong river case) (보 관리수위에 따른 주변 지하수위 변동특성 분석 (낙동강 중심으로))

  • Oh, Jun Oh;Kim, Min Gyu;Park, Jae Hyeon;Jun, Sang Mi
    • Proceedings of the Korea Water Resources Association Conference
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    • 2017.05a
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    • pp.118-118
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    • 2017
  • 4대강 사업으로 인하여 장래 치수 및 물부족현상과 가뭄에 대비한 용수 확보를 위해 하도준설과 보의 설치, 중소규모댐 건설, 농업용저수지 증설 등이 진행되었다. 그중 낙동강에는 8개 대형보가 건설되었다. 하지만 보 건설로 인하여 주변 지역 지하수위가 상승하여 주변 농경지나 저지대가 침수될 가능성이 있어 4대강 사업의 문제점의 하나로 지적되어 왔다. 이에 본 연구에서는 낙동강 유역에 건설된 보로 인하여 상승한 하천수위가 보 주변지역에 미치는 영향을 알아보기 위하여 8개보 주변의 연구대상지역을 선정하고 지하수 모델(Visual-MODFLOW)을 이용하여 보 관리수위 및 함양량 변화에 따른 지하수 유동과 지하수 변화를 분석하였다. 각 연구대상지역별 지하수위 변동특성 분석 순서는 보 건설 후(현재상태)에 대하여 정류상태 보정을 실시한 후 보 관리수위 시나리오를 정하고 그에 따른 분기별 함양량을 적용하여 부정류 모의를 실시하였다. 그 결과 각 연구대상지역의 지하수위는 낙동강 하천수위와 비슷하게 형성되는 것으로 평가되었으며, 낙단보의 경우 분기별 지하수위 변화가 0.1m ~ 0.2m로 함양량 변화에 따른 지하수위 변동이 가장 작게 평가되었다. 상주보의 경우 분기별 지하수위 변화가 1.5m ~ 2.1m로 함양량 변화에 따른 지하수위 변동이 가장 큰 것으로 평가되었다. 이러한 지하수위 변화는 하천주변 농가의 재배 작물 수확량 및 품질에 직접적인 영향을 줄 수 있어 농번기인 2분기(4월 ~ 6월)와 4분기(10월 ~ 12월)의 경우 보 관리수위를 주변 재배작물에 따라 운영한다면 보 건설로 인한 주변 지하수위 상승으로 인한 영향을 최소화 할 수 있을 것으로 판단된다. 향후 한강, 금강, 영산강에 건설된 보 주변에 대한 지하수위 변화특성 연구가 필요할 것으로 판단되며 본 연구 결과를 바탕으로 보 관리수위 결정의 기초자료로 활용할 수 있을 것이라 판단 된다.

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Effect of Sensory Stimulation Type on Brain Activity in Elderly Persons with Mild Cognitive Impairment

  • Koo, Japung;Hwang, Hyunsook
    • Journal of International Academy of Physical Therapy Research
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    • v.10 no.1
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    • pp.1700-1705
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    • 2019
  • Background: Mild cognitive impairment (MCI) is also called as aging related memory damage. Decreased cognitive function due to aging is known to be associated with the frontal lobe. Alpha wave is generated in the dominance in the frontal lobe or a wide range of regions in the brain, it should be doubted that the brain function might be degraded. Objective: To determine the effect of sensory stimulation type on learning and brain activity pattern of elderly persons with MCI. Design: Randomized Controlled Trial (single blind) Methods: Twenty elderly persons aged more than 65 with MCI were randonmized to simultaneous visual/auditory stimulation group (SVASG) and or auditory stimulation group (ASG). Ten peoples were assigned to each group and lectroencephalogram test was performed to individuals. In the electroencephalogram test, electroencephalography of prior to sensory stimulation, and during sensory stimulation were measured to compare brain activity pattern according to the study groups and measurement period. Results: The relative alpha power due to a sensory stimulation type showed that the SVASG significantly decreased in the left frontal lobe and the left parietal lobe statistically compared to those of the ASG while sensory stimulation was given (p<.05). The relative beta power due to a sensory stimulation type showed that the SVASG significantly increased in the left and right frontal lobes, the left and right parietal lobes, and the left temporal lobe statistically compared to those of the ASG while sensory stimulation was given (p<.05). Conclusions: Electroencephalographic analysis showed that the type of sensory stimulation can affect the brain activity pattern. However, the effects were not studied that which brain activity pattern help to improved cognitive function of elderly persons with mild cognitive impairment.

Variation of the Morphological Characteristics in the Accessions of Zoysia Species and Their Hybrid Lines (Zoysiagrass 수집계통들과 종간교배계통들의 형태적 특성들의 변이)

  • 김형기;김기선;주영규;홍규현;김경남;이재필;모숙연;김두환
    • Asian Journal of Turfgrass Science
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    • v.10 no.1
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    • pp.1-11
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    • 1996
  • Fifty accessions in Zoysia species and forty-one hybrid lines were evaluated in order to detect analyze the genectic variation of Zoysiagrasses and to obtain the basic information for breeding. 1.Plant height ranged from 13 to 34.5cm, leaf length from 7 to 26cm, leaf width from 2 to 7mm, and first leaf height from 1.1 to 8.5cm 2. The correlations among plant height, leaf length and first-leaf height were high, but leaf Width was correlated only With leaf length. 3. Stolon length was varied from 10 to 108cm, number of stolons from 12 to 53, internode length from 2 to 6.1cm and coverage percentage from 10 to 90%. 4.There were correlation among stolen length, number of stolons, internode length and coverage percentage except between stolen and internode length. 5.M1J and MC2 showed the highest level in stolen length, number of stolons and coverage percentage. Therefore they will be the best breeding materials for the purpose of fast covering. 6.According to the analysis on October 26, 1995, yellow color-change rate of leaves ranged from 5 to 85%, red color-change from 0 to 75% and sum of yellow and red change from 20 to 95%. Speciallty M2M1 and FL-41 kept green color untill early December, indicating that they had the late dormancy. 7. Visual assessment of stolon length and number of stolons, showed similar tendency With actually measured data. 8. Shoot density was very high in M2M1 and S2, and showed negative correlation with leaf width. 9. It is known in Korea that the darker green color of lawngrass is, the better it looks. There were 11 lines with dark green color leaves such as J 85-10, Meyer in Z. japonira, one asacession in Z. matrella and M2M1, M2S8, JM2, 55C2 in hybrid lines.

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PIV measurement and numerical investigation on flow characteristics of simulated fast reactor fuel subassembly

  • Zhang, Cheng;Ju, Haoran;Zhang, Dalin;Wu, Shuijin;Xu, Yijun;Wu, Yingwei;Qiu, Suizheng;Su, G.H.
    • Nuclear Engineering and Technology
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    • v.52 no.5
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    • pp.897-907
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    • 2020
  • The flow characteristics of reactor fuel assembly always intrigue the designers and the experimentalists among the myriad phenomena that occur simultaneously in a nuclear core. In this work, the visual experimental method has been developed on the basis of refraction index matching (RIM) and particle image velocimetry (PIV) techniques to investigate the detailed flow characteristics in China fast reactor fuel subassembly. A 7-rod bundle of simulated fuel subassembly was fabricated for fine examination of flow characteristics in different subchannels. The experiments were performed at condition of Re=6500 (axial bulk velocity 1.6 m/s) and the fluid medium was maintained at 30℃ and 1.0 bar during operation. As for results, axial and lateral flow features were observed. It is shown that the spiral wire has an inhibitory effect on axial flow and significant intensity of lateral flow mixing effect is induced by the wire. The root mean square (RMS) of lateral velocity fluctuation was acquired after data processing, which indicates the strong turbulence characteristics in different flow subchannels.