• 제목/요약/키워드: Local Region Growing

검색결과 107건 처리시간 0.028초

순위 차 확산 필터를 이용한 스페클 잡음 제거 (Speckle Noise Removal by Rank-ordered Differences Diffusion Filter)

  • 예철수
    • 대한원격탐사학회지
    • /
    • 제25권1호
    • /
    • pp.21-30
    • /
    • 2009
  • 본 논문의 목적은 원격 탐사 영상에서 잡음을 제거하기 위해 중심 화소와 통계적으로 유사한 이웃화소들을 선택하늘 방법을 제시하고 이 결과를 평균 곡률 확산과 결합하는 방법을 제시하는데 있다. 균일한 밝기값 영역에 속하는 화소들을 검출하기 위해 이웃 화소들을 순차적으로 선택할 때 그 선택하는 순서에 따라 선택된 영역의 통계적 특성이 달라지므로 이웃 화소의 선택 순서는 매우 중요하다. 본 논문에서는 통계적으로 유사한 특성을 가지는 이웃 화소를 선택하기 위해서 중심 화소와 이웃 화소의 밝기값 차를 계산하고 이를 크기 순으로 정렬하여 얻어지는 순위 차 벡터(rank-ordered differences vector)를 이용하는 효과적인 방법을 제안한다. 순위 차 벡터의 항들을 영역 확장 방법을 이용하여 균일 순위 차 벡터(homogeneous rank-ordered differences vector)와 이상점 순위 차 벡터 (outlier rank-ordered differences vector)로 분할한다. 균일 순위 차 벡터의 항에 속하는 이웃 화소에 대해서만 중심 화소의 밝기값 갱신에 기여하도록 확산 계수를 선택적으로 할당하는 라인 프로세스를 평균 곡률 확산에 결합한다. 제안한 방법은 모든 이웃 화소를 이용하여 중심 화소의 밝기값을 갱신하는 기존의 잡음 제거 필터에 비해 잡음 제거 효과가 뛰어남을 항공 영상 및 TerraSAR-X 위성 영상을 이용한 실험을 통해 확인하였다.

LiDAR 자료를 이용한 산림 CO2 흡수량 산출 연구 (Study of CO2 Absorption in Forest by Airborn LiDAR Data)

  • 고신영;박정기;조기성
    • 대한공간정보학회지
    • /
    • 제21권4호
    • /
    • pp.29-35
    • /
    • 2013
  • 산림지역에서 이산화탄소흡수량 산출을 위해서는 현지산림조사와 영상정보 등의 원격탐사 자료를 이용함으로써 흉고직경이나 수고와 같은 산림 탄소흡수량 추정에 필요한 기본자료를 정량적으로 수집하여 활용한다. 그러나 여전히 현장조사의 비중이 높고 혼효림이 많은 국내 산림 여건상 취득된 산림정보의 정확도가 낮은 실정이다. 따라서 본 연구에서는 LiDAR 자료를 이용하여 경사기반 영역확장법을 적용하여 수목의 수직적 구조를 파악하고 수목 정점추출 알고리즘을 통한 개체목의 수고 및 개체수를 파악하여 이를 현장조사를 통한 자료로부터 도출된 수고-흉고직경 관계식에 대입하여 정량적인 이산화탄소흡수량 산출에 필요한 기본데이터를 산출 할 수 있었다. 또한 총 3종류의 수목에 대한 이산화탄소흡수량을 계산하고 단위면적당 이산화탄소흡수량을 추정할 수 있었다.

자연경관형 및 역사문화형의 농촌 마을길 계획 (A Study on Planning Trails of Natural and Historic-Cultural Landscapes in Rural Villages)

  • 김은자;이유경;임창수;최진아;김상범;박미정
    • 농촌계획
    • /
    • 제20권2호
    • /
    • pp.159-171
    • /
    • 2014
  • This study discusses developing historical trails and ecological trails in rural area. Since the leisure time and interests in environment and health have been increasing, the number of hikers who enjoy the beautiful landscape and regional culture through the exploration of natural regions has been growing. However, these various road haven't been related to the rural village in many cases, so it is necessary to make some alternatives for revitalizing the region and improving incomes of non farm. Therefore this study suggested the applications of rural trail plan that fits for a scale of the rural village and local characteristics. This research divided forms of the rural village road into type of the natural landscape resource (Gangreung Anbandegi Village) and that of the historical culture resource (Yongin Hakil Village) according to amenity resources of objective village. The plan for village road basically made by the best of valuable resources of village unit, connected existing 'Trail' of other departments to the village and suggested a case of plan applied to the field so as to emphasize characteristics of rural area. It should be possible to induce hikers to rural area and be suggested as a measure for improvement of village image, regional vitalization and incomes of non farm.

Restoration effects influenced by plant species and landscape context in Young-il region, Southeast Korea: Structural and compositional assessment on restored forest

  • Cho, Yong-Chan;Kim, Kyung-Soon;Pi, Jung-Hun;Lee, Chang-Seok
    • Journal of Ecology and Environment
    • /
    • 제39권1호
    • /
    • pp.1-10
    • /
    • 2016
  • Despite it has been mentioned that the successful restoration in landscape level was achieved in the Young-il soil erosion control project, quantitative evaluation of restored plant communities (Alnus firma as introduced species and Pinus thunbergii as native species) was hardly founded. Light availability, litter and woody debris cover, and forest structure and composition were determined for 500 m2 band-quadrat in three forest types. Abiotic factors of Q. serrata stands, as reference forest, and A. firma stands were similar but not for P. thunbergii stands. There were no significant difference on mean stem density (stems ha-1, H = 3.6, p = 0.162), and the mean basal area of each stand had marginal significance (m2 ha-1, H = 5.7, p = 0.058) among stands as total basal area was higher with the order of A. firma (21.4 m2 ha-1), P. thunbergii (19.8 m2 ha-1) and Q. serrata (16.2 m2 ha-1). Restoration of vegetation structure was more effective in fast-growing and N-fixing A. firma, as introduced species plantation. However, result of MRPP, NMS ordination and ISPAN for herbaceous layer, not for tree and shrub species composition, indicated that restoration of ground vegetation was likely influenced highly from local environment. Propagule availability from landscape context such as connectedness to natural vegetation and management practices in restored isolated stands are available explanations for restoration effects and gaps between restored plantations and secondary oak forest.

교근부 보툴리눔 A형 독소(Botulinum Toxin Type A) 주사가 쥐의 턱뼈 성장에 미치는 영향 (Effects of Botulinum Toxin Type A Injection into Masseter Muscle on the Jaw Growth in Rats)

  • 윤승현;김지연;김성택
    • 구강회복응용과학지
    • /
    • 제23권2호
    • /
    • pp.171-178
    • /
    • 2007
  • Botulinum toxin type A (BTX-A) has a local effect at the neuromuscular junction by blocking acetylcholine release and thus causing paralysis and atrophy of the affected muscles. In dentistry, Botulinum toxin type A(BTX-A) is used for the treatment of masseteric hypertrophy, temporomandibular disorder, and severe bruxism related neurologic disorder. We hypothesized that the muscle atrophy after BTX-A injection into masseter muscle in growing rats, could affect the jaw growth. The purpose of this study was to determine the effects of the BTX-A injected into the masseter muscle on the jaw growth in rats. Rats were divided into four groups(group 1; control group, group 2; saline injection group, group 3; BTX-A injection group, group 4; baseline control group). Group 4 was sacrificed at the beginning of the experiment to provide baseline values of jaw measurements. The weight, length and width of jaw in those groups were measured every weeks. This study reported that the mandibular body length, condylar length, coronoid process length, anterior region height, coronoid process height and condylar height of the jaw in BTX-A injection group were shorter than those of the control and saline injection groups(P<0.05). In conclusion, BTX-A injected into the masseter muscle may affect the undergrowth of the jaw in rats.

라이트필드 초해상도와 블러 제거의 동시 수행을 위한 적대적 신경망 모델 (Adversarial Framework for Joint Light Field Super-resolution and Deblurring)

  • 조나단 사무엘;백형선;박인규
    • 방송공학회논문지
    • /
    • 제25권5호
    • /
    • pp.672-684
    • /
    • 2020
  • 시차 기반 영상처리에 대한 연구들이 증가함에 따라 저해상도 및 모션 블러된 라이트필드 영상을 복원하는 연구는 필수적이 되었다. 이러한 기법들은 라이트필드 영상 향상 과정으로 알려져 있으나 두 개 이상의 문제를 동시에 해결하는 기존의 연구는 거의 존재하지 않는다. 본 논문에서는 라이트필드 공간 영역 초해상도 복원과 모션 블러 제거를 동시 수행하는 프레임워크를 제안한다. 특히, 저해상도 및 6-DOF 모션 블러된 라이트필드 데이터셋으로 훈련하는 간단한 네트워크를 생성한다. 또한 성능을 향상하기 위해 생성적 적대 신경망의 지역 영역 최적화 기법을 제안하였다. 제안한 프레임워크는 정량적, 정성적 측정을 통해 평가하고 기존의 state-of-the-art 기법들과 비교하여 우수한 성능을 나타냄을 보인다.

Electrical, Electronic Structure and Optical Properties of Undoped and Na-doped NiO Thin Films

  • Denny, Yus Rama;Lee, Kangil;Seo, Soonjoo;Oh, Suhk Kun;Kang, Hee Jae;Yang, Dong-Seok
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
    • /
    • pp.193.1-193.1
    • /
    • 2014
  • This study was to investigate the electronic structure and optical properties of Na doped into NiO thin film using XPS and REELS. The films were grown by electron beam evaporation with varying the annealing temperature. The relationship between the electrical characteristics with the local structure of NiO thin films was also discussed. The x-ray photoelectron results showed that the Ni 2p spectra for all films consist of Ni 2p3/2 which indicate the presence of Ni-O bond from NiO phase and for the annealed film at temperature above $200^{\circ}C$ shows the coexist Ni oxide and Ni metal phase. The reflection electron energy loss spectroscopy spectra showed that the band gaps of the NiO thin films were slightly decreased with Na-doped into films. The Na-doped NiO showed relatively low resistivity compared to the undoped NiO thin films. In addition, the Na-doped NiO thin films deposited at room temperature showed the best properties, such as a p-type semiconducting with low electrical resistivity of $11.57{\Omega}.cm$ and high optical transmittance of ~80% in the visible light region. These results indicate that the Na doping followed by annealing process plays a crucial in enhancing the electrical and optical properties of NiO thin films. We believe that our results can be a good guide for those growing NiO thin films with the purpose of device applications, which require deposited at room temperature.

  • PDF

Experimental Investigation of Horizontal Buoyant Discharges from a Rosette-type Riser Using LIF System

  • Kwon, Seok Jae;Seo, Il Won;Kim, Ho Jung
    • 한국수자원학회:학술대회논문집
    • /
    • 한국수자원학회 2004년도 학술발표회
    • /
    • pp.463-467
    • /
    • 2004
  • Rosette-type diffusers with four-ports per riser are constructed in relatively shallow water in Korea. However, the trajectorial bending phenomena due to lower-pressure inside the surrounded buoyant jets on the riser was not considered in most models and was not observed without any experimental results. The buoyant jet behavior affected by the bending effect where there have been growing interests need to be verified experimentally and need to be preceded in the analysis of the characteristics of the buoyant jets oil a riser. The hydraulic model experiments have been carried out to investigate the characteristics of the behavior of horizontal buoyant jets discharged from a Rosette-type riser with four ports as well as single port over a certain range of the experimental conditions including initial momentum and initial buoyancy using LIF (Laser Induced Fluorescence) system to obtain concentration fields. The intensity of the fluorescent light in each pixel on the images obtained from LIF system with the tracer of Rhodamine H was converted to the local dye concentration with a set of calibration procedures to account for the non-uniform distribution of light intensity and the attenuation of light energy by water medium. The experimental results shows that the trajectories from Your ports tend to bend more and more to the inner side with the increase of the densimetric Froude number while the buoyant jet from a single port rises up without any bending phenomena. The previous models, VISJET and Seo et al. (2002), do not simulate the trajectories well except the region before the bending section. This study will focus on the analysis of the behavior of the buoyant jets for mainly a Rosette-type riser by conducting hydraulic model experiments using LIF system.

  • PDF

A Robust Mobile Video Streaming in Heterogeneous Emerging Wireless Systems

  • Oh, Hayoung
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제6권9호
    • /
    • pp.2118-2135
    • /
    • 2012
  • With the rapid development of heterogeneous emerging wireless technologies and numerous types of mobile devices, the need to support robust mobile video streaming based on the seamless handover in Future Internet is growing. To support the seamless handover, several IP-based mobility management protocols such as Mobile IPv6 (MIPv6), fast handover for the MIPv6 (FMIPv6), Hierarchical MIPv6 (HMIPv6) and Proxy Mobile IPv6 (PMIPv6) were developed. However, MIPv6 depreciates the Quality-of-Service (QoS) and FMIPv6 is not robust for the video services in heterogeneous emerging wireless networks when the Mobile Node (MN) may move to another visited network in contrast with its anticipation. In Future Internet, the possibility of mobile video service failure is more increased because mobile users consisting of multiple wireless network interfaces (WNICs) can frequently change the access networks according to their mobility in heterogeneous wireless access networks such as 3Generation (3G), Wireless Fidelity (Wi-Fi), Worldwide Interoperability for Microwave Access (WiMax) and Bluetooth co-existed. And in this environment, seamless mobility is coupled according to user preferences, enabling mobile users to be "Always Best Connected" (ABC) so that Quality of Experience is optimised and maintained. Even though HMIPv6 and PMIPv6 are proposed for the location management, handover latency enhancement, they still have limit of local mobility region. In this paper, we propose a robust mobile video streaming in Heterogeneous Emerging Wireless Systems. In the proposed scheme, the MN selects the best-according to an appropriate metric-wireless technology for a robust video streaming service among all wireless technologies by reducing the handover latency and initiation time when handover may fail. Through performance evaluation, we show that our scheme provides more robust mechanism than other schemes.

광대뼈에 발생한 뼈내혈관종의 증례 보고 (Intraosseous Hemangioma of the Zygoma: A Case Report)

  • 정민경;권용석;전동근;이명철;김지남;신동혁;김완섭;최현곤
    • 대한두경부종양학회지
    • /
    • 제37권1호
    • /
    • pp.33-37
    • /
    • 2021
  • Intraosseous hemangioma is a rare, benign vascular tumor of endothelial origin. It accounts for fewer than 1% of all hemangiomas, and very rarely occurs in the face. Intraosseous hemangioma usually presents as an asymptomatic lesion, but symptoms can occur due to the mass effect. The authors describe a case of intraosseous hemangioma of the zygoma with a review of the relevant literature. A 44-year-old man presented with a chief complaint of painless swelling on the left zygomatic region that had been slowly growing for the past year. On physical examination, a hard, non-movable mass in a deep layer was palpated. On computed tomography performed to evaluate its layers and extent, trabeculation was found inside the mass, but the lack of destruction of the surrounding bone suggested that the mass was benign. Complete surgical excision was performed under local anesthesia. After complete excision of the mass, slight erosions remained on the cortical bone of the zygoma, but because it was small enough not to cause a facial deformity such as depression or asymmetry, no additional reconstructive procedure was performed. There were no symptoms or recurrence during a 8-month follow-up period.