• 제목/요약/키워드: Region Growing Method

검색결과 241건 처리시간 0.024초

Adaptive Wavelet Neural Network Based Wind Speed Forecasting Studies

  • Chandra, D. Rakesh;Kumari, Matam Sailaja;Sydulu, Maheswarapu;Grimaccia, F.;Mussetta, M.
    • Journal of Electrical Engineering and Technology
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    • 제9권6호
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    • pp.1812-1821
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    • 2014
  • Wind has been a rapidly growing renewable power source for the last twenty years. Since wind behavior is chaotic in nature, its forecasting is not easy. At the same time, developing an accurate forecasting method is essential when wind farms are integrated into the power grid. In fact, wind speed forecasting tools can solve issues related to grid stability and reserve allocation. In this paper 30 hours ahead wind speed profile forecast is proposed using Adaptive Wavelet Neural Network (AWNN). The implemented AWNN uses a Mexican hat mother Wavelet, and Morlet Mother Wavelet for seven, eight and nine levels decompositions. For wind speed forecasting, the time series data on wind speed has been gathered from the National Renewable Energy Laboratory (NREL) website. In this work, hourly averaged 10-min wind speed data sets for the year 2004 in the Midwest ISO region (site number 7263) is taken for analysis. Data sets are normalized in the range of [-1, 1] to improve the training performance of forecasting models. Total 8760 samples were taken for this forecasting analysis. After the forecasting phase, statistical parameters are calculated to evaluate system accuracy, comparing different configurations.

In Sacco Ruminal Degradation Characteristics of Chemical Components in Fresh Zoysia japonica and Miscanthus sinensis Growing in Japanese Native Pasture

  • Ogura, S.;Kosako, T.;Hayashi, Y.;Dohi, H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권1호
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    • pp.41-47
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    • 2001
  • Ruminal degradation characteristics of dry matter (DM), neutral detergent fiber (NDF) and crude protein (CP) in fresh leaves of two Japanese native grasses (Zoysia japonica and Miscanthus sinensis) and one sown temperate grass (Dactylis glomerata) were investigated by an in sacco method in spring (mid-May), summer (mid-July) and autumn (mid-September). Japanese native grasses had higher NDF and lower CP concentrations than D. glomerata, and the CP concentration in native grasses decreased in autumn. Ruminal degradability of DM, NDF and CP was lower in native grasses than in D. glomerata (p<0.05) in all seasons. DM and NDF degradability decreased in summer for Z. japonica and D. glomerata, while it decreased in autumn for M. sinensis. CP degradability in Z. japonica was constant throughout the seasons, whereas that in M. sinensis greatly decreased in summer and autumn (p<0.05). It was concluded that Z. japonica could stably supply ruminally digestible nutrients for grazing animals in Japanese native pasture. However, the degradation characteristics of freshly chopped native grasses did not fit the exponential model of $D=a+b(1-e^{-ct})$ proposed by Ørskov and McDonald.

Fe-Cr-Ni강 용접금속부의 미세편석에 관한 해석 (Analysis of Microsegregation in Fe-Cr-Ni Weld Metal)

  • 박준민;박종민;안상곤;이창희;윤의박
    • Journal of Welding and Joining
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    • 제16권5호
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    • pp.56-66
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    • 1998
  • During solidification or welding of alloys, the solute redistribution brings out microsegregation. The microsegregation causes the formation of non-equilibrium second phases, shrinkage and porosity degrading mechanical/chemical properties Therefore, it has been required to predict microsegregation quantitatively. To predict the degree of microsegregation, more exact and appropriate computer simulation technique has been actively used during last two decades. To predict the degree of microsegregation in weld metal, an advanced two dimensional model was suggested. In the new model, both primary and secondary arm regions were defined for the analysis region. The growth in the primary arm regina was assumed to be a planar for effective calculation. Especially, for the growth of a secondary arm, a simple and effective mathematical function was established to show the growing pattern, the solute diffusion in the solid phase was calculated by finite difference method (FDM). The solid-liquid interface movement was considered to be in local equilibrium state. The experiments for welding of 310S stainless steel were carried out in order to examined the reasonability and feasibility of this model. The concentration profiles of the solute predicted by this model were compared with those obtained from experimental works.

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Online Burning Material Pile Detection on Color Clustering and Quaternion based Edge Detection in Boiler

  • Wang, Weixing;Liu, Sheng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권1호
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    • pp.190-207
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    • 2015
  • In the combustion engineering, to decrease pollution and increase production efficiency, and to optimally keep solid burning material amount constant in a burner online, it needs a smart method to detect the amount variation of the burning materials in a high temperature environment. This paper presents an online machine vision system for automatically measuring and detecting the burning material amount inside a burner or a boiler. In the camera-protecting box of the system, a sub-system for cooling is constructed by using the cooling water circulation techqique. In addition, the key and intelligent step in the system is to detect the pile profile of the variable burning material, and the algorithm for the pile profile tracing was studied based on the combination of the gey level (color) discontinuity and similarity based image segmentation methods, the discontinuity based sub-algorithm is made on the quaternion convolution, and the similarity based sub-algorithm is designed according to the region growing with multi-scale clustering. The results of the two sub-algoritms are fused to delineate the final pile profile, and the algorithm has been tested and applied in different industrial burners and boilers. The experiements show that the proposed algorithm works satisfactorily.

염료감응형 태양전지에서 효율 향상을 위한 Quantum Dot 재료로서 Ag가 도핑된 ZnO의 발광 특성 연구 (Luminescence Properties of Ag Doped ZnO as Quantum Dot Materials for Improving Efficiency of Dye-sensitized Solar Cell)

  • 김현주;이동윤;송재성
    • 한국전기전자재료학회논문지
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    • 제17권9호
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    • pp.988-993
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    • 2004
  • Luminescence characteristics of Ag-doped ZnO as the quantum dot materials to increasing the efficiency on dye-sensitized solar cells (DSC) have been studied. Ag doped ZnO powder was produced by the self-sustaining combustion process using ultrasonic spraying heating method. Luminescence wavelength region of the ZnO by Ag doping was shifted to longer wavelength. Tn the case of the Ag doped ZnO powder, broad luminescence spectrum centered on 600nm was observed. On the other hand, we compared PL data of RTA treated ZnO:Ag film at various temperatures because the front electrode of solar cell was in need of the sintering process. In XRD and PL data for RTA treated film at the 500$^{\circ}C$ showed good property. And, it was found that the grain size wasn't growing but only optical property was changed. According to the result of XRD, PL, absorption, emission spectrum and DV-X${\alpha}$ used in theoretical calculation, it is considered to be possible to use Ag doped ZnO as quantum dot material for improving DSC efficiency.

지역사회 혁신을 촉진하기 위한 농촌활성화지원센터의 역할 (The Role of Rural Revitalization Support Centers in Facilitating Community Innovation in Korea)

  • 임상봉
    • 한국지역사회생활과학회지
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    • 제25권1호
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    • pp.39-49
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    • 2014
  • This study identifies the necessity and importance of innovation in rural communities and highlights the role of rural revitalization support centers in facilitating the diffusion of community innovation. The study provides a literature review and employs the survey method to verify the arguments. There is an urgent need for rural communities to be distinct, attractive, and competitive in the wake of globalization. It is clear that they must recognize the need to facilitate innovation under growing trends toward trade liberalization, environment-oriented life styles, diversified consumer needs, and a knowledge-based society. The results provide support for the legitimacy of establishing rural revitalization support centers to help community leaders and local stakeholders develop their communities. More specifically, rural communities should employ R&D outcomes from diverse fields and capacity building by community members, leaders, and local governments to foster sustainable growth by overcoming limitations in spatial access and resources. The results suggest that rural revitalization support centers can be established as intermediary organizations that can be operated to facilitate community innovation in rural development. In addition, these centers should play key roles such as empowering communities, facilitating region-specific rural development policies, motivating R&D applications for rural development, encouraging rural development networks. Further, close attention should be paid to facilitate mutual learning by expanding networks and interactions between these centers.

Implementation of Digital Image Processing for Coastline Extraction from Synthetic Aperture Radar Imagery

  • Lee, Dong-Cheon;Seo, Su-Young;Lee, Im-Pyeong;Kwon, Jay-Hyoun;Tuell, Grady H.
    • 한국측량학회지
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    • 제25권6_1호
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    • pp.517-528
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    • 2007
  • Extraction of the coastal boundary is important because the boundary serves as a reference in the demarcation of maritime zones such as territorial sea, contiguous zone, and exclusive economic zone. Accurate nautical charts also depend on well established, accurate, consistent, and current coastline delineation. However, to identify the precise location of the coastal boundary is a difficult task due to tidal and wave motions. This paper presents an efficient way to extract coastlines by applying digital image processing techniques to Synthetic Aperture Radar (SAR) imagery. Over the past few years, satellite-based SAR and high resolution airborne SAR images have become available, and SAR has been evaluated as a new mapping technology. Using remotely sensed data gives benefits in several aspects, especially SAR is largely unaffected by weather constraints, is operational at night time over a large area, and provides high contrast between water and land areas. Various image processing techniques including region growing, texture-based image segmentation, local entropy method, and refinement with image pyramid were implemented to extract the coastline in this study. Finally, the results were compared with existing coastline data derived from aerial photographs.

Genetic Diversity in the Coat Protein Genes of Prune dwarf virus Isolates from Sweet Cherry Growing in Turkey

  • Ozturk, Yusuf;Cevik, Bayram
    • The Plant Pathology Journal
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    • 제31권1호
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    • pp.41-49
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    • 2015
  • Sweet cherry is an important fruit crop with increasing economical value in Turkey and the world. A number of viruses cause diseases and economical losses in sweet cherry. Prune dwarf virus (PDV), is one of the most common viruses of stone fruits including sweet cherry in the world. In this study, PDV was detected from 316 of 521 sweet cherry samples collected from 142 orchards in 10 districts of Isparta province of Turkey by double antibody sandwich-enzyme linked immunosorbent assay (DAS-ELISA). The presence of PDV in ELISA positive samples was confirmed in 37 isolates by reverse transcription- polymerase chain reaction (RT-PCR) method. A genomic region of 862 bp containing the coat protein (CP) gene of PDV was re-amplified from 21 selected isolates by RT-PCR. Amplified DNA fragments of these isolates were purified and sequenced for molecular characterization and determining genetic diversity of PDV. Sequence comparisons showed 84-99% to 81-100% sequence identity at nucleotide and amino acid level, respectively, of the CP genes of PDV isolates from Isparta and other parts of the world. Phylogenetic analyses of the CP genes of PDV isolates from different geographical origins and diverse hosts revealed that PDV isolates formed different phylogenetic groups. While isolates were not grouped solely based on their geographical origins or hosts, some association between phylogenetic groups and geographical origins or hosts were observed.

초등학교 자연과 생작은생물생 단원의 수업 실태 분석 (An Analysis of the Instructional State of the Unit 생Small Living Things′ in the Elementary School Science)

  • 최도성;최규식;남철우;김정길;김석중;송판섭;한광래;한효의
    • 한국초등과학교육학회지:초등과학교육
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    • 제19권1호
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    • pp.157-170
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    • 2000
  • The purpose of this study is to survey the instructional state of the unit 'Small Living Things' in the Elementary School Science. for this study, 100 teachers were surveyed on teaching-learning practices. More specifically, questions were asked on the degree of accomplishing instruction objectives, frequency of field . study, experimental preparation, alternative instructional methods, amount of preparation, availability of reference books for teachers and availability of information materials on the Kwangju region. Our results show that teachers find the objectives related to the collection of living things for class experiments and the task of growing and observing them the most difficult to accomplish. It was reported that 38% of teachers have actually conducted field trips. The obstacles listed in going out on field study range from lack of knowledge of appropriate places, lack of time, to safety concerns. The most difficult problem in teaching this unit was preparing proper instructional materials, regardless of teacher's gender, career, and interest. Most respondents let children provide the experimental subjects. Teachers with collection experience tend to provide for the experimental materials themselves. Our Analysis also reveals that more than 70% of the respondents do not have adequate knowledge of the species dealt with in the unit. Gender, career, and interest area of the teachers did not make any difference (p< .05). In the case that proper experimental subjects have not been prepared, VTR, textbooks, and charts were reported as the most frequently used alternative instruction aids. The level of content and amount of knowledge contained in this unit were found to be appropriate. Information on instruction materials and experiment-observation were obtained through the teaching manual or periodicals (58%), information materials on the region(20%), and fellow teachers (12%). Reference books for teachers and materials on the region are perceived to be inadequate in order of importance in the areas of preparation method, level-wise learning guide, experimental observation, and information on species covered in text. Overall, it was judged that the highest concern was with obtaining experimental materials, and teacher's reference books and materials on the region need to be reinforced to allow teachers to more fully utilize them. Development and distribution of proper instruction-learning materials to the children's level is also required.

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인삼포장에서 뿌리섞음병원균의 진단을 위한 RT-PCR KIT의 개발 (Development of RT-PCR Kit for Diagnosis of Pathogenic Agent of Ginseng Root Rot in the Ginseng Field)

  • 도은수
    • 한국자원식물학회지
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    • 제16권1호
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    • pp.40-48
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    • 2003
  • C. destructans는 인삼에서 가장 문제가 되고 있는 뿌리섞음병을 유발하는 매우 중요한 미생물이다. 현재까지 정상적인 인삼포장이나 폐포지에서도 이 병원균의 농도를 조사할 만한 방법이 없어 이를 쉽게 조사함으로서 인삼 예정지 관린시 도움을 줄 수 있는 새로운 방법이 절실이 요구되고 있다. 본 연구에서는 nested PCR이란 분자생물학적 방법을 이용하여 효과적으로 매우 낮은 농도의 C. destructans을 검출할 수 있는 방법을 개발하였다. 2개의 universal ITS primers(ITS5F와 ITS4R)을 사 용 하 여 Cylindrocarpon spp.의 rDNA로부터 ITS영역을 증폭하였다. 이어 C. destructans의 specific primer(Nest 1 과 Nest 2)을 사용하여 최적의 PCR조건으로 재증폭시켜 밴드를 확인하였다. 또한 이런 2번의 과정을 4개의 primer를 동시에 사용함으로서 한번에 확인할 수 있는 방법을 개발하였으며 이에 따른 PCR조건도 확립하였다. 따라서 본 방법에 의해서 인삼포장의 토양에서 채취된 매우 낮은 농도의 wild type C. destructans spore로부터 성공적으로 positive band을 확인함으로써 추후 인삼포장의 선정 및 4년생에서 6년까지(홍삼포) 재배기간등의 예측에 활용 될 것으로 생각된다.