• Title/Summary/Keyword: Scale method

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Ship Response Estimation Method in Multi-Directional Waves Using Real Sea Experiments (실선시험기법을 이용한 다방향파중에서의 선박의 응답추정법)

  • 조효제;강일권;김종철
    • Journal of Ocean Engineering and Technology
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    • v.12 no.1
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    • pp.135-142
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    • 1998
  • In this study, the frequency transfer function of motions are predicted from the result of a full-scale seakeeping trials. Because the real sea has the characteristics of multi-directional waves,we compare the results in the one directional waves with ones in the directional waves. For calculation of the frequency transfer function in the directional waves, Takezawa's inverse estimation method was introduced and the frequency ranges were divided into three parts in order to consider following seas. The full-scale seakeeping trials was executed in the south sea of Korea using the stern trawler. Those results show that analysis method of the multi-directional waves is more reliable than that of one directional waves, and confirm the possibility of applying this method to the full-scale seakeeping trials.

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A Study on Finding the K Shortest Paths for the Multimodal Public Transportation Network in the Seoul Metropolitan (수도권 복합 대중교통망의 복수 대안 경로 탐색 알고리즘 고찰)

  • Park, Jong-Hoon;Sohn, Moo-Sung;Oh, Suk-Mun;Min, Jae-Hong
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.607-613
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    • 2011
  • This paper reviews search methods of multiple reasonable paths to implement multimodal public transportation network of Seoul. Such a large scale multimodal public transportation network as Seoul, the computation time of path finding algorithm is a key and the result of path should reflect route choice behavior of public transportation passengers. Search method of alternative path is divided by removing path method and deviation path method. It analyzes previous researches based on the complexity of algorithm for large-scale network. Applying path finding algorithm in public transportation network, transfer and loop constraints must be included to be able to reflect real behavior. It constructs the generalized cost function based on the smart card data to reflect travel behavior of public transportation. To validate the availability of algorithm, experiments conducted with Seoul metropolitan public multimodal transportation network consisted with 22,109 nodes and 215,859 links by using the deviation path method, suitable for large-scale network.

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A "Thru-Short-Open" De-embedding Method for Accurate On-Wafer RF Measurements of Nano-Scale MOSFETs

  • Kim, Ju-Young;Choi, Min-Kwon;Lee, Seong-Hearn
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.12 no.1
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    • pp.53-58
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    • 2012
  • A new on-wafer de-embedding method using thru, short and open patterns sequentially is proposed to eliminate the errors of conventional methods. This "thru-short-open" method is based on the removal of the coupling admittance between input and output interconnect dangling legs. The increase of the de-embedding effect of the lossy coupling capacitance on the cutoff frequency in MOSFETs is observed as the gate length is scaled down to 45 nm. This method will be very useful for accurate RF measurements of nano-scale MOSFETs.

Research on the efficient illumination method in iris recognition at a distance (원거리 홍채 인식에서 효율적 조명 조사방법에 관한 연구)

  • Jo, Hyun-Su;Bae, Kwang-Hyuk;Park, Kang-Ryoung;Kim, Jai-Hie
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.969-970
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    • 2008
  • This paper proposes illumination-efficient iris image capturing method. face capture method for extraction of iris pattern with one high resolution camera needs a large scale near infrared illumination. we replace high-resolution camera with co-optic-axial combination between wide view camera and narrow view camera. because this method needs small scale illumination that illuminate only narrow camera viewing angle, we can capture iris pattern image with small scale near infrared illumination.

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Fast Detection of Distributed Global Scale Network Attack Symptoms and Patterns in High-speed Backbone Networks

  • Kim, Sun-Ho;Roh, Byeong-Hee
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.2 no.3
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    • pp.135-149
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    • 2008
  • Traditional attack detection schemes based on packets or flows have very high computational complexity. And, network based anomaly detection schemes can reduce the complexity, but they have a limitation to figure out the pattern of the distributed global scale network attack. In this paper, we propose an efficient and fast method for detecting distributed global-scale network attack symptoms in high-speed backbone networks. The proposed method is implemented at the aggregate traffic level. So, our proposed scheme has much lower computational complexity, and is implemented in very high-speed backbone networks. In addition, the proposed method can detect attack patterns, such as attacks in which the target is a certain host or the backbone infrastructure itself, via collaboration of edge routers on the backbone network. The effectiveness of the proposed method are demonstrated via simulation.

Crop Field Extraction Method using NDVI and Texture from Landsat TM Images

  • Shibasaki, Ryosuke;Suzaki, Junichi
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.159-162
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    • 1998
  • Land cover and land use classification on a huge scale, e.g. national or continental scale, has become more and more important because environmental researches need land cover: And land use data on such scales. We developed a crop field extraction method, which is one of the steps in our land cover classification system for a huge area. Firstly, a crop field model is defined to characterize "crop field" in terms of NDVI value and textual information Textual information is represented by the density of straight lines which are extracted by wavelet transform. Secondly, candidates of NDVI threshold value are determined by "scale-space filtering" method. The most appropriate threshold value among the candidates is determined by evaluating the line density of the area extracted by the threshold value. Finally, the crop field is extracted by applying level slicing to Landsat TM image with the threshold value determined above. The experiment demonstrates that the extracted area by this method coincides very well with the one extracted by visual interpretation.

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A Meshless Method and its Adaptivity for Stress Concentration Problems (응력집중문제의 해석을 위한 적응적 무요소절점법에 관한 연구)

  • 이상호;전석기;김효진
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1997.10a
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    • pp.16-23
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    • 1997
  • The Reproducing Kernel Particle Method (RKPM), one of the popular meshless methods, is developed and applied to stress concentration problems. Since the meshless methods require only a set of particles (or nodes) and the description of boundaries in their formulation, the adaptivity can be implemented with much more ease than finite element method. In addition, due to its intrinsic property of multiresolution, the shape function of RKPM provides us a new criterion for adaptivity. Recently, this multiple scale Reproducing Kernel Particle Method and its adaptive procedure have been formulated for large deformation problems by the authors. They are also under development for damage materials and localization problems. In this paper the multiple scale RKPM for linear elasticity is presented and the adaptive procedure is applied to stress concentration problems. Therefore, this work may be regarded as the edition of linear elasticity in the complete framework of multiple scale RKPM and the associated adaptivity.

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Decentralized Sliding Mode Feedback Control Design Method for a Large Scale System with a Poly topic Models (폴리토픽 모델을 갖는 대규모 시스템을 위한 비집중화 슬라이딩 모드 제어기 설계)

  • Choi, Han-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.16 no.1
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    • pp.1-4
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    • 2010
  • Based on the sliding mode control theory, a decentralized controller design method is developed for a large scale system with a poly topic model. In terms of LMIs, we derive sufficient conditions for the existence of the decentralized controller guaranteeing a stable sliding motion. We also give an LMI-based control design algorithm. Finally, the proposed method is applied to decentralized stabilization of double-inverted pendulums. Simulation results show that our method gives not only the robust stability but perfect rejection of norm-bounded uncertainties.

AN INTERFERENCE FRINGE REMOVAL METHOD BASED ON MULTI-SCALE DECOMPOSITION AND ADAPTIVE PARTITIONING FOR NVST IMAGES

  • Li, Yongchun;Zheng, Sheng;Huang, Yao;Liu, Dejian
    • Journal of The Korean Astronomical Society
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    • v.52 no.2
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    • pp.49-55
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    • 2019
  • The New Vacuum Solar Telescope (NVST) is the largest solar telescope in China. When using CCDs for imaging, equal-thickness fringes caused by thin-film interference can occur. Such fringes reduce the quality of NVST data but cannot be removed using standard flat fielding. In this paper, a correction method based on multi-scale decomposition and adaptive partitioning is proposed. The original image is decomposed into several sub-scales by multi-scale decomposition. The region containing fringes is found and divided by an adaptive partitioning method. The interference fringes are then filtered by a frequency-domain Gaussian filter on every partitioned image. Our analysis shows that this method can effectively remove the interference fringes from a solar image while preserving useful information.

Integration of a Large-Scale Genetic Analysis Workbench Increases the Accessibility of a High-Performance Pathway-Based Analysis Method

  • Lee, Sungyoung;Park, Taesung
    • Genomics & Informatics
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    • v.16 no.4
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    • pp.39.1-39.3
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    • 2018
  • The rapid increase in genetic dataset volume has demanded extensive adoption of biological knowledge to reduce the computational complexity, and the biological pathway is one well-known source of such knowledge. In this regard, we have introduced a novel statistical method that enables the pathway-based association study of large-scale genetic dataset-namely, PHARAOH. However, researcher-level application of the PHARAOH method has been limited by a lack of generally used file formats and the absence of various quality control options that are essential to practical analysis. In order to overcome these limitations, we introduce our integration of the PHARAOH method into our recently developed all-in-one workbench. The proposed new PHARAOH program not only supports various de facto standard genetic data formats but also provides many quality control measures and filters based on those measures. We expect that our updated PHARAOH provides advanced accessibility of the pathway-level analysis of large-scale genetic datasets to researchers.