• Title/Summary/Keyword: Merging point

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Advanced Lane Change Assist System for Automatic Vehicle Control in Merging Sections : An algorithm for Optimal Lane Change Start Point Positioning (고속도로 합류구간 첨단 차로변경 보조 시스템 개발 : 최적 차로변경 시작 지점 Positioning 알고리즘)

  • Kim, Jinsoo;Jeong, Jin-han;You, Sung-Hyun;Park, Janhg-Hyon;Young, Jhang-Kyung
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.14 no.3
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    • pp.9-23
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    • 2015
  • A lane change maneuver which has a high driver cognitive workload and skills sometimes leads to severe traffic accidents. In this study, the Advanced Lane Change Assist System (ALCAS) was developed to assist with the automatic lane changes in merging sections which is mainly based on an automatic control algorithm for detecting an available gap, determining the Optimal Lane Change Start Point (OLCSP) in various traffic conditions, and positioning the merging vehicle at the OLCSP safely by longitudinal automatic controlling. The analysis of lane change behavior and modeling of fundamental lane change feature were performed for determining the default parameters and the boundary conditions of the algorithm. The algorithm was composed of six steps with closed-loop. In order to confirm the algorithm performance, numerical scenario tests were performed in various surrounding vehicles conditions. Moreover, feasibility of the developed system was verified in microscopic traffic simulation(VISSIM 5.3 version). The results showed that merging vehicles using the system had a tendency to find the OLCSP readily and precisely, so improved merging performance was observed when the system was applied. The system is also effective even during increases in vehicle volume of the mainline.

Assessment and merging technique for GPM satellite precipitation product using ground based measurement (GPM 위성 강우자료의 검증과 지상관측 자료를 통한 강우 보정 기법)

  • Baik, Jongjin;Park, Jongmin;Kim, Kiyoung;Choi, Minha
    • Journal of Korea Water Resources Association
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    • v.51 no.2
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    • pp.131-140
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    • 2018
  • Precipitation is a key variable to enhance the understanding of water cycle system and secure and manage the water resources efficiently. In this study, we evaluated the feasibility of GPM precipitation datasets through comparison with the 92 ASOS sites in South Korea during 2015. Additionally, three merging techniques (i.e., Geographical Differential Analysis, Geographical Ratio Analysis, Conditional Merging) were applied to improve accuracy of precipitation by fusing the advantages from point and satellite-based datasets. The results of this study are as follows. 1) GPM dataset indicated slightly overestimation with compared ASOS dataset, especially high uncertainties in summer season. 2) Validation of three merging techniques through jackniffe cross-validation showed that uncertainty were decreased as the spatial resolution increased. Especially, conditional merging showed the best performance among three methods.

Merging points for the operation of a LSP tunnel based on an optical label stack structure (광 패킷 레이블 스택구조 기반의 LSP 터널운용을 위한 머징 포인트)

  • Kim Kyoung-Mok;Oh Young-Hwan
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.42 no.5 s.335
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    • pp.5-12
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    • 2005
  • Establishment of bandwidth and effective traffic processing are required to treat various traffics according to a rapid increase in Internet traffic. A wavelength based transferring method was introduced to support a broadband bandwidth according to this requirement, and consequently, a label processing procedure has been investigated to treat various traffics. This paper introduces a regular shape of stack structure in order to solve the present MPLS label stack processing unit, and analyzes the relationship to label merging, which is initiated between label merging inside and outside the LSP tunnel. By applying an adaptive label structure and merging point a hierarchical label, which is aroused in the GMPLS, can be uniformly simplified and improved from the perspective of cost and processing time at a node

The Design of Method for Efficient Processing of Small Files in the Distributed System based on Hadoop Framework (하둡 프레임워크 기반 분산시스템 내의 작은 파일들을 효율적으로 처리하기 위한 방법의 설계)

  • Kim, Seung-Hyun;Kim, Young-Geun;Kim, Won-Jung
    • The Journal of the Korea institute of electronic communication sciences
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    • v.10 no.10
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    • pp.1115-1122
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    • 2015
  • Hadoop framework was designed to be suitable for processing very large files. On the other hand, when processing the Small Files, it waste the resource of a distributed system, and occur performance degradation. It is shown noticeable the more the Small Files. This problem is caused by the Small Files, it can be solved through the merging of associated Small Files. But a way of merging of Small Files has some limited point. in this paper, examines existing limit of merging method, design merging method Small Files for effective process.

Center estimation of the n-fold engineering parts using self organizing neural networks with generating and merge learning (뉴런의 생성 및 병합 학습 기능을 갖는 자기 조직화 신경망을 이용한 n-각형 공업용 부품의 중심추정)

  • 성효경;최흥문
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.34C no.11
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    • pp.95-103
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    • 1997
  • A robust center estimation tecnique of n-fold engineering parts is presented, which use self-organizing neural networks with generating and merging learning for training neural units. To estimate the center of the n-fold engineering parts using neural networks, the segmented boundaries of the interested part are approximated to strainght lines, and the temporal estimated centers by thecosine theorem which formed between the approximaged straight line and the reference point, , are indexed as (.sigma.-.theta.) parameteric vecstors. Then the entries of parametric vectors are fed into self-organizing nerual network. Finally, the center of the n-fold part is extracted by mean of generating and merging learning of the neurons. To accelerate the learning process, neural network uses an adaptive learning rate function to the merging process and a self-adjusting activation to generating process. Simulation results show that the centers of n-fold engineering parts are effectively estimated by proposed technique, though not knowing the error distribution of estimated centers and having less information of boundaries.

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Development of Merging Algorithm between 3-D Objects and Real Image for Augmented Reality

  • Kang, Dong-Joong
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.100.5-100
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    • 2002
  • A core technology for implementation of Augmented Reality is to develop a merging algorithm between interesting 3-D objects and real images. In this paper, we present a 3-D object recognition method to decide viewing direction toward the object from camera. This process is the starting point to merge with real image and 3-D objects. Perspective projection between a camera and 3-dimentional objects defines a plane in 3-D space that is from a line in an image and the focal point of the camera. If no errors with perfect 3-D models were introduced in during image feature extraction, then model lines in 3-D space projecting onto this line in the image would exactly lie in this plane. This observa...

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Correlation between mergers and AGN activity : a case study with MARK 478

  • Hong, Ju-Eun;Im, Myung-Shin
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.2
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    • pp.34.1-34.1
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    • 2010
  • Studies suggest that activities in luminous AGNs, residing mostly in early-type galaxies, are triggered by merging. However, the observational evidence for the connection between mergers and AGN activity is not clear yet because tracer of the past merging activities such as tidal tail, shell are often too faint. To see if we can reveal the merging features with a small telescope, we observed an AGN, MARK 478, at z=0.077 with long exposure time (7550 seconds) in V filter at Maidanak observatory. Our 2-D fitting analysis shows that the host galaxy of MARK 478 has the bulge to the total luminosity ratio of 0.3. And the residual image, after subtracting point spread function (PSF), bulge and disk components, shows that the host galaxy has an arm-like feature that could be a spiral arm or a feature from minor merging. We also show that the structural parameters obtained from our 2-D fitting match well with those derived from HST image. The promising result suggests that studies of low redshift AGN host galaxies are possible with data from a small telescope. In order to allow a statistical analysis, we hope to expand our sample size in future.

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Merging and Splitting of Coronal Holes through a Solar Cycle

  • Jang, Min-Hwan;Choe, G.S.;Hong, Sun-Hak;Woods, Tom
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.99-99
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    • 2011
  • A statistical study of coronal hole merging and splitting has been performed through Solar Cycle 23. The NOAA/SESC solar synoptic maps are examined to identify inarguably clear events of coronal hole merging and splitting. The numbers of merging events and splitting events are more or less comparable regardless of the phase in the solar cycle. The number of both events, however, definitely shows the phase dependence in the solar cycle. It apparently has a minimum at the solar minimum whereas its maximum is located in the declining phase of the sunspot activity, about a year after the second peak in Solar Cycle 23. There are more events of merging and splitting in the descending phase than in the ascending phase. Interestingly, no event is found at the local minimum between the two peaks of the sunspot activity. This trend can be compared with the variation of the average magnetic field strength and the radial field component in the solar wind through the solar cycle. In Ulysses observations, both of these quantities have a minimum at the solar minimum while their maximum is located in the descending phase, a while after the second peak of the sunspot activity. At the local minimum between the two peaks in the solar cycle, the field strength and the radial component both have a shallow local minimum or an inflection point. At the moment, the physical reason for these resembling tendencies is difficult to understand with existing theories. Seeing that merging and splitting of coronal holes are possible by passage of opposite polarity magnetic structures, we may suggest that the energizing activities in the solar surface such as motions of flux tubes are not exactly in phase with sunspot generation, but are more active some time after the sunspot maximum.

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The Flow Characteristics with Variation of Nozzle-to-nozzle Angles on Unventilated Dual Jests (이중제트에서 노즐과 노즐사이의 각도 변화에 따른 유동 특성)

  • Kim, Dong-Keon;Kim, Moon-Kyoung;Yoon, Soon-Hyun
    • Journal of Advanced Marine Engineering and Technology
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    • v.32 no.8
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    • pp.1231-1239
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    • 2008
  • The characteristics of flow on unventilated dual jets was experimentally investigated. The two nozzles each with an aspect ratio of 20 were separated by 6 nozzle widths. Reynolds number based on nozzle width was set to 5,000 by nozzle exit velocity. All measurements were made over a range of nozzle-to-nozzle angles from $0^{\circ}$ to $25^{\circ}$. The particle image velocimetry and pressure transducer were employed to measure turbulent velocity components and mean static pressure, respectively. It was shown that a recirculation zone with sub-atmospheric static pressure was bounded by the inner shear layers of the individual jets and the nozzles plated. As nozzle-to-nozzle inclined angles were decreased, it was found that the spanwise turbulent intensity is greater than the streamwise turbulent intensity in the merging region. In the combined region, the velocity of dual jets agree well with that of single jet, but the turbulence intensity of dual jets not agree with that of single jet.