• 제목/요약/키워드: Poor Area

검색결과 1,499건 처리시간 0.028초

가우시안 잡음에서 변형된 LLAH 알고리즘의 성능 분석 (Performance Analysis of Modified LLAH Algorithm under Gaussian Noise)

  • 류호섭;박한훈
    • 한국멀티미디어학회논문지
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    • 제18권8호
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    • pp.901-908
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    • 2015
  • Methods of detecting, describing, matching image features, like corners and blobs, have been actively studied as a fundamental step for image processing and computer vision applications. As one of feature description/matching methods, LLAH(Locally Likely Arrangement Hashing) describes image features based on the geometric relationship between their neighbors, and thus is suitable for scenes with poor texture. This paper presents a modified LLAH algorithm, which includes the image features themselves for robustly describing the geometric relationship unlike the original LLAH, and employes a voting-based feature matching scheme that makes feature description much simpler. Then, this paper quantitatively analyzes its performance with synthetic images in the presence of Gaussian noise.

한국산 보리수나무속 식물의 분포 및 생육지 토양 특성 (Geographical Distribution and Soil Characteristics of Elaeagnus Plants in Korea)

  • You, Young-Han;Kim, Kyung-Bum;An, Chung-Sun;Kim, Joon-Ho;Song, Seung-Dal
    • The Korean Journal of Ecology
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    • 제17권2호
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    • pp.159-170
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    • 1994
  • The geographical distribution and soil characteristics of Korean Elaeagnus plants were investigated by literatures, field survey and soil analysis. Deciduous E. umbellata was distributed throughout the Korean peninsula including western and southern islands. Distribution area of evergreen Elaeagnus plants was classified into three groups; E. macrophylla and E. glabra belonged to group l occurring in the southern, western and eastern islands; E. submacrophylla to group 2 occurring in the southern and western islands; E. maritima and E. ankaii to group 3 in the southern islands only. Deciduous E. umbellata appeared euryeciously from poor soil to rich one, whereas evergreen Elaegnus plants appeared stenoeciously in haline soil near coast.

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홍수특성과 지하공간침수의 관계 검토 (Relationship between Flood Characteristics and Underground Inundation)

  • 이대영;이건행;경민수;김형수
    • 한국방재학회:학술대회논문집
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    • 한국방재학회 2007년도 정기총회 및 학술발표대회
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    • pp.367-370
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    • 2007
  • In recent, the utilization of underground in urban area is increased as subway, store, and others but we have done a few studies for the inundation of underground due to flooding. So, we investigate the examples of underground inundation and the causes of inundation for flood events. And the relationship between flood characteristics and underground inundation is analyzed through the frequency of rainfall which is made by annual multi maximum series. As a result, most of underground is inundated by high frequency of rainfall. And there are some cases that the underground is inundated by low frequency of rainfall because of poor drainage system and characteristics of location.

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이종 플래스틱의 초음파 용접성에 대한 연구 (A study on the ultrasonic weldability of the dissimilar plastics)

  • 이철구
    • Journal of Welding and Joining
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    • 제9권1호
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    • pp.48-57
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    • 1991
  • Welding of dissimilar materials is an area of growing importance in the automotive, aerospace, electronics medical and other domestic appliance industries. This study investigated the ultrasonic welding of dissimilar polymers. Two amorphous and two semicrystalline polymers were used, utilizing all possible welding combinations. For each combination of dissimilar materials, the weldabilitys of the joint was evaluated as a function of weld time, amplitude of vibration and pressure. The joint was also examined microscopically to analyze the melting and flow of the materials. It was generally around found that welding of amorphus polymers resulted in very poor joints. Welding of the amorphous polymers together and welding of the semicrystalline polymers together produced good joints.

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Girbanr Hills의 식생 (Vegetation Studies of Girbanr Hills, District Swat, Pakistan)

  • Hussain, Farrukh;Mohammad Ilyas;Kil, Bong-Seop
    • The Korean Journal of Ecology
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    • 제18권2호
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    • pp.207-218
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    • 1995
  • Five non-stratified plant communities, Dichanthium-Artemisia-Themeda, Dichanthium- Plectranthes-Themeda, Plectranthes-Carex-Myrine, Heteropogon- Dichanthium-Dodonaea and Artemisia-Cynodon-Ber-beris were recognized in Girbanr hills, District Swat, during autumn, 1992. The indices of similarity showed that the communities were dissimilar. The percentage of leptophyllous and nanophyllous, terophytic and nanophanerophytic species were higher than other groups. These indicate dry and disturben conditions. Due to autumn season most of the species were entering in dormant stage. There was no tree layer on southern slopes while northern slopes had a poor layer of Pinus roxburghii. Deforestation, uprooting, terrace cultivation and overgrazing followed by erosion are the main ecological problems. The presence of isolated trees of Pinus roxburghii and stunted Olea ferruginea indicate that the original vegetation might have been of chirpine or Olea-Pinus type. The area having resource potential can be changed into a forest or rangeland by proper protection and management. Suggestions in favour of improvement are given.

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파노라마방사선사진에서 골형태 계측과 구내표준필름에서 구리당량치의 상관관계 (The correlationship between mandibular radiomorphometric indices in panorama and bone mineral density in Cu-equivalent image of intraoral film)

  • 김재덕
    • Imaging Science in Dentistry
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    • 제33권3호
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    • pp.131-135
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    • 2003
  • Purpose: To determine whether the mandibular radiomorphometric indices in panoramic radiography are correlated with the bone mineral density of Cu-equivalent images in intraoral film. Materials and Methods: The bone mineral density (BMD) of the mandibular premolar area was measured in the Cu-equivalent image of intraoral film. The Panoramic Mandibular Index (PMI) and Mandibular Cortical Width (MCW) were measured in panoramic radiographs of six dry mandibles, and the Pearson correlation between PMI, MCW, and BMD were tested. Results: There were no significant correlations between PMI and BMD (r = 0.280), nor between MCW and BMD (r =0.237). Conclusion: The results show that PMI and MCW were poor diagnostic indicators of mandibular BMD in the six dry mandibles used in this study. The correlationship between the mandibular radiomorphometric indices (PMI and MCW) and mandibular BMD needs to be researched further using large in vivo patient samples.

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3투사렌즈방식 LCD 프로젝션 TV의 엔진 냉각에 관한 연구 (A study on the cooling method for LCD projection TV with 3 projection lens)

  • 김철환;조여욱
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.1253-1257
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    • 2004
  • We have developed new rear LCD Projection TV engine with 3 projection lens. It has high brightness and contrast ratio, however poor cooling conditions. If optical components close to light source, optical components are damaged on high temperature, especially the blue among RGB colors is weakest by heat In this study, a new enhanced cooling method of LCD projection TV with 3 lens is shown: the best suited design of duct and relations between LCD panel and polarizer lifetime with changed area of duct.

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군산시 공원주변의 동물상과 개발에 따른 생물학적인 영향 및 대책 (Fauna of Some Parks Around Kunsan-City and Biological Impact on the Developments of These Parks)

  • 김세천;윤창호;서홍렬
    • 환경영향평가
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    • 제7권1호
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    • pp.23-34
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    • 1998
  • This study was carried out to survey the fauna of some parks around Kunsan-city and to establish biological impact on the development of those parks. Among the fauna surveyed, insects consist of 74 species in 49 families and 13 orders. The insect fauna was poor, because the environment was made of simple flora and mostly farmland. Fish in the reservoir of Wolmyong-Park consist of 7 species. Among them, Ctenopharyngodon idellus is an exotic species and characterized with its voracious plantfeeding. This fish severely destroyed the habitats and spawning sites of other sympatric fish. For the conservation of non-exotic fish, birds, and mammals in the area, the integrated biological direction would be needed.

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자가 치유 기법을 이용한 고가용도 웹 서버 클러스터 (High Availability Web Server Cluster Using Self-healing Technique)

  • 정지영;김영로
    • 디지털산업정보학회논문지
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    • 제5권1호
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    • pp.23-32
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    • 2009
  • Although the web is becoming a widely accepted medium, it provides relatively poor performance and low availability. A cluster consists of a collection of interconnected stand-alone computers working together and provides a high-availability solution in application area such as web services or information systems. Web server clusters require a high-availability service with a proactive and practical fault management. However, as the system complexity grows, it is not easy to meet the requirement. Therefore, web server clusters must have self-fault management capability for meeting high-availability requirement. In this paper, we propose high availability web server clusters using self-healing technique with a minimal human intervention. Our experimental results show that a proposed method can be used to improve the availability of web server clusters.

CNN 기반의 IEEE 802.11 WLAN 프레임 포맷 검출 (CNN based IEEE 802.11 WLAN frame format detection)

  • 김민재;안흥섭;최승원
    • 디지털산업정보학회논문지
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    • 제16권2호
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    • pp.27-33
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    • 2020
  • Backward compatibility is one of the key issues for radio equipment supporting IEEE 802.11, the typical wireless local area networks (WLANs) communication protocol. For a successful packet decoding with the backward compatibility, the frame format detection is a core precondition. This paper presents a novel frame format detection method based on a deep learning procedure for WLANs affiliated with IEEE 802.11. Considering that the detection performance of conventional methods is degraded mainly due to the poor performances in the symbol synchronization and/or channel estimation in low signal-to-noise-ratio environments, we propose a novel detection method based on convolutional neural network (CNN) that replaces the entire conventional detection procedures. The proposed deep learning network provides a robust detection directly from the receive data. Through extensive computer simulations performed in the multipath fading channel environments (modeled by Project IEEE 802.11 Task Group ac), the proposed method exhibits superb improvement in the frame format detection compared to the conventional method.