• Title/Summary/Keyword: Global State

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Road Surface Marking Detection for Sensor Fusion-based Positioning System (센서 융합 기반 정밀 측위를 위한 노면 표시 검출)

  • Kim, Dongsuk;Jung, Hogi
    • Transactions of the Korean Society of Automotive Engineers
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    • v.22 no.7
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    • pp.107-116
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    • 2014
  • This paper presents camera-based road surface marking detection methods suited to sensor fusion-based positioning system that consists of low-cost GPS (Global Positioning System), INS (Inertial Navigation System), EDM (Extended Digital Map), and vision system. The proposed vision system consists of two parts: lane marking detection and RSM (Road Surface Marking) detection. The lane marking detection provides ROIs (Region of Interest) that are highly likely to contain RSM. The RSM detection generates candidates in the regions and classifies their types. The proposed system focuses on detecting RSM without false detections and performing real time operation. In order to ensure real time operation, the gating varies for lane marking detection and changes detection methods according to the FSM (Finite State Machine) about the driving situation. Also, a single template matching is used to extract features for both lane marking detection and RSM detection, and it is efficiently implemented by horizontal integral image. Further, multiple step verification is performed to minimize false detections.

Changes in the Earth's Spin Rotation due to the Atmospheric Effects and Reduction in Glaciers

  • Na, Sung-Ho;Cho, Jungho;Kim, Tu-Hwan;Seo, Kiweon;Youm, Kookhyoun;Yoo, Sung-Moon;Choi, Byungkyu;Yoon, Hasu
    • Journal of Astronomy and Space Sciences
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    • v.33 no.4
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    • pp.295-304
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    • 2016
  • The atmosphere strongly affects the Earth's spin rotation in wide range of timescale from daily to annual. Its dominant role in the seasonal perturbations of both the pole position and spinning rate of the Earth is once again confirmed by a comparison of two recent data sets; i) the Earth orientation parameter and ii) the global atmospheric state. The atmospheric semi-diurnal tide has been known to be a source of the Earth's spin acceleration, and its magnitude is re-estimated by using an enhanced formulation and an up-dated empirical atmospheric S2 tide model. During the last twenty years, an unusual eastward drift of the Earth's pole has been observed. The change in the Earth's inertia tensor due to glacier mass redistribution is directly assessed, and the recent eastward movement of the pole is ascribed to this change. Furthermore, the associated changes in the length of day and UT1 are estimated.

A Study on Clean Agent Fire Extinguishing Ability Using Nitrogen and Novec Mixtures Gas (질소와 노벡 혼합가스를 이용한 청정소화약제의 소화성능에 관한 연구)

  • Lim, Woo-Sub;Jung, Jong-Jin;Nam, Dong-gun;SaKong, Seong-Ho;Kim, Jong-Won;Choi, Kenu-Joo
    • Journal of the Korean Society of Safety
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    • v.23 no.6
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    • pp.76-83
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    • 2008
  • In the course of increasing in human and material damage caused by fire, it is an important research field to develop clean extinguishing agent which does no harm to global environment as well as has a good extinguishing efficiency. This research is a basic step to develop a new clean extinguishing agent. In order to get a satisfactory result, we tested fire extinguishing ability using nitrogen and Novec mixtures gas which are inert gas and new clean extinguishing agent. We used Cup Burner Test made by international standard ISO-14520 regulations of gaseous extinguishing agent ability test, and the fuels used in the test are n-heptane, methanol, ethanol, iso-propanol and 1-butanol. The experimental results of flame extinguishing concentration are n-heptane 6.54%, methanol 8.47%, ethanol 6.98%, isopropanol 6.10% and butanol 6.54% by pure Novec agent. So the finding is that a new clean agent, Novec has an efficient extinguishing ability in a state of gas. Also, in a test as to mixtures gas of nitrogen and Novec, it has a good result for minimum oxygen concentration is under 16%.

Adaptive Medical Image Compression Based on Lossy and Lossless Embedded Zerotree Methods

  • Elhannachi, Sid Ahmed;Benamrane, Nacera;Abdelmalik, Taleb-Ahmed
    • Journal of Information Processing Systems
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    • v.13 no.1
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    • pp.40-56
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    • 2017
  • Since the progress of digital medical imaging techniques, it has been needed to compress the variety of medical images. In medical imaging, reversible compression of image's region of interest (ROI) which is diagnostically relevant is considered essential. Then, improving the global compression rate of the image can also be obtained by separately coding the ROI part and the remaining image (called background). For this purpose, the present work proposes an efficient reversible discrete cosine transform (RDCT) based embedded image coder designed for lossless ROI coding in very high compression ratio. Motivated by the wavelet structure of DCT, the proposed rearranged structure is well coupled with a lossless embedded zerotree wavelet coder (LEZW), while the background is highly compressed using the set partitioning in hierarchical trees (SPIHT) technique. Results coding shows that the performance of the proposed new coder is much superior to that of various state-of-art still image compression methods.

A Comparative Analysis of Music Similarity Measures in Music Information Retrieval Systems

  • Gurjar, Kuldeep;Moon, Yang-Sae
    • Journal of Information Processing Systems
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    • v.14 no.1
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    • pp.32-55
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    • 2018
  • The digitization of music has seen a considerable increase in audience size from a few localized listeners to a wider range of global listeners. At the same time, the digitization brings the challenge of smoothly retrieving music from large databases. To deal with this challenge, many systems which support the smooth retrieval of musical data have been developed. At the computational level, a query music piece is compared with the rest of the music pieces in the database. These systems, music information retrieval (MIR systems), work for various applications such as general music retrieval, plagiarism detection, music recommendation, and musicology. This paper mainly addresses two parts of the MIR research area. First, it presents a general overview of MIR, which will examine the history of MIR, the functionality of MIR, application areas of MIR, and the components of MIR. Second, we will investigate music similarity measurement methods, where we provide a comparative analysis of state of the art methods. The scope of this paper focuses on comparative analysis of the accuracy and efficiency of a few key MIR systems. These analyses help in understanding the current and future challenges associated with the field of MIR systems and music similarity measures.

Latent Heat Flux over the Global Ocean

  • Kubota, Masahisa
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.644-648
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    • 2002
  • Though it was difficult of globally monitor latent heat flux aver the ocean for many years, the situation is rapidly changing by the use of satellite data. Since a bulk formula is used to estimate turbulent heat flux using satellite data, we need wind speed, sea surface temperature and specific humidity data. However, it is not easy to accurately estimate specific humidity using satellite data. Now several algorithms for estimating specific humidity have been proposed and applied to construct latent heat flux data sets. Latent heat flux data sets derived from satellite data such as J-OFURO, HOAPS and GSSTF are available at present. Since the algorithm and used satellite data are not the same between them. the characteristics of each data set may be different. Therefore, it is important to clarify the difference between each data set and investigate the cause of the difference in latent heat flux estimates. In this paper we summarize the present state of the art with regard to the turbulent heat flux estimation by using satellite data. Also we present the comparison results of latent heat flux fields including not only satellite-derived flux fields but also analysis fields.

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A DAMAGE IDENTIFICATION METHOD FOR THIN CYLINDRICAL SHELLS (얇은 원통형 쉘에 발생한 손상 규명)

  • Oh H.;Cho J.;Lee U.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.10a
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    • pp.394-399
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    • 2005
  • In this paper, a structural damage identification method (SDIM) is developed to identify the line crack-like directional damages generated within a cylindrical shell. First, the equations of motion fur a damaged cylindrical shell are derived. Based on a theory of continuum damage mechanics, a small material volume containing a directional damage is represented by the effective orthotropic elastic stiffness, which is dependent of the size and the orientation of the damage with respect to the global coordinates. The present SDIM is then derived from the frequency response function (FRF) directly solved from the dynamic equations of the damaged cylindrical shell. In contrast with most existing SDIMs which require the modal parameters measured in both intact and damaged states, the present SDIM requires only the FRF-data measured in damaged state. By virtue of utilizing FRF-data, one may choose as many sets of excitation frequency and FRF measurement point as needed to acquire a sufficient number of equations fer damage identification analysis. The numerically simulated damage identification tests are conducted to study the feasibility of the present SDIM.

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Flame Diagnosis Using Neuro-Fuzzy Learning Algorithm (뉴로퍼지학습 알고리듬을 이용한 연소상태진단)

  • Lee, Tae-Yeong;Kim, Seong-Hwan;Lee, Sang-Ryong
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.4
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    • pp.587-595
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    • 2002
  • Recent trend changes a criterion for evaluation of humors that environmental problems are raised as a global issue. Burners with higher thermal efficiency and lower oxygen in the exhaust gas, evaluated better. To comply with environmental regulations, burners must satisfy the NO/sub x/ and CO regulation. Consequently, 'good burner'means one whose thermal efficiency is high under the constraint of NO/sub x/ and CO consistency. To make existing burner satisfy recent criterion, it is highly recommended to develop a feedback control scheme whose output is the consistency of NO/sub x/ and CO. This paper describes the development of a real time flame diagnosis technique that evaluate and diagnose the combustion states, such as consistency of components in exhaust gas, stability of flame in the quantitative sense. In this paper, it was proposed on the flame diagnosis technique of burner using Neuro-Fuzzy algorithm. This study focuses on the relation of the color of the flame and the state of combustion. Neuro-Fuzzy loaming algorithm is used in obtaining the fuzzy membership function and rules. Using the constructed inference algorithm, the amount of NO/sub x/ and CO of the combustion gas was successfully inferred.

The Present State of Wind Turbine Condition Monitoring System (풍력 터빈 상태 감시 시스템 현황)

  • Clark, Timothy J.;Bauer, Richard F.;Rasmussen, James R.;Jeong, J.H.;Lee, B.J.;Lee, C.M.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.92-97
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    • 2005
  • The $9 billion US global wind energy market is experiencing dramatic growth with installed generating capacity up 500% from 7,600 MW at the end of 1997 to nearly 39,300 MW at the end of 2003. With an average annual increase approaching 32%, wind is the world's fastest growing energy source on a percentage basis, and its growth is forecast to continue a double-digit pace into the next decade 1. While much of this growth is fueled by government decisions that are favorable to 'green' or renewable Power, it is also fueled by advances in wind turbine technology as evidenced by larger, more sophisticated machines. As a result, wind turbines are becoming more established as an economically viable alternative to fossil-fueled power generation. Today, wind 'farms' - consisting of anywhere from a single turbine to as many as several hundred turbines - are an important component of the world's source of electric energy.

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Finite Element Modal Analysis of a Spinning Flexible Disk-Spindle System Considering the Flexiblity of Supporting Structures and an Actuator in a HDD (지지구조와 액츄에이터의 유연성을 고려한 HDD 유연 회전 디스크-스핀들 시스템의 유한 요소 고유 진동 해석)

  • Seo, Chan-Hee;Lee, Chang-Suk;Jang, Gun-Hee;Lee, Ho-Sung
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.330-336
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    • 2005
  • This paper presents a method to analyze the vibration of a flexible spinning disk-spindle system with FDBs, flexible base structure and an actuator in a HDD by using the FEM. Finite element equations of each component of a HDD spindle system from the spinning flexible disk to the flexible base plate are consistently derived by satisfying the geometric compatibility in the internal boundary between each component. A global matrix equation obtained by assembling the finite element equations of each substructure is transformed to a state-space matrix-vector equation, and both damped natural frequencies and modal damping ratios are calculated by using the restarted Arnoldi iteration method. The validity of the proposed method is verified by comparing the simulated natural frequencies, mode shapes with the experimental results.

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