• Title/Summary/Keyword: POLAR

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Multichannel Gabor Filler and Log-Polar Transform for Content-Based Image Retrieval (다채널 Gabor 필터와 Log-Polar 변환을 사용한 내용기반 영상 검색)

  • Park, Hyun;Moon, Young-Shik
    • Proceedings of the IEEK Conference
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    • 2000.06c
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    • pp.181-184
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    • 2000
  • In this paper, we propose new features for describing texture images by using multi-channel Gabor filter and log-polar transform based on human visual system (HVS). Gabor features are extracted by the mean and standard deviation of energy in Gabor response, followed by Fourier series extension. Log-polar features are extracted by log-polar transform and projection. The proposed texture descriptor performs reasonably well with less number of features than other texture descriptors, which has been verified by experiments using some texture images of MPEG-7 data set.

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Obstacle a voidance using VFH (Vector Field Histogram) in four legged robot (VFH(Vector Field Histogram)을 이용한 4족 로봇의 장애물 회피)

  • Jung, Hyun-Ryong;Kim, Young-Bae
    • Proceedings of the KIEE Conference
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    • 2003.11b
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    • pp.23-26
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    • 2003
  • The vector field histogram(VFH) uses a two-dimensional Cartesian histogram grid as a world model. The VFH method subsequently employs a two-stage data-reduction process in order to compute the desired control commands for the vehicle. In the first stage the histogram grid is reduced to a one dimensional polar histogram that is constructed around the robot's momentary location. Each sector in the polar histogram contains a value representing the polar obstacle density in that direction. In the second stage, the algorithm selects the most suitable sector from among all polar histogram sectors with a low polar obstacle density, and the steering of the robot is aligned with that direction. We applied this algorithm to our four-legged robot.

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A STUDY ON QUADRATIC CURVES AND GENERALIZED ECCENTRICITY IN POLAR TAXICAB GEOMETRY

  • Kim, Kyung Rok;Park, Hyun Gyu;Ko, Il Seog;Kim, Byung Hak
    • Korean Journal of Mathematics
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    • v.22 no.3
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    • pp.567-581
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    • 2014
  • Over the years, there has been much research conducted on quadratic curves and the set of points with the generalized notion of eccentricity in a plane with metrics such as taxicab distance or Chinese-checker distance. On the other hand, polar taxicab distance has been newly proposed on the polar coordinate system, a type of curvilinear coordinate system, to overcome the limitation of pre-existing metrics in terms of describing curved routes. Previous study has looked into the fundamental properties of this metric. From this point of view, we study the quadratic curves and the set of points with the generalized notion of eccentricity in a plane with polar taxicab distance.

Taxonomic Study of Suborder Calcaxonia (Alcyonacea: Octocorallia: Anthozoa) from King Sejong Station, Antarctic

  • Song, Jun-Im;Hwang, Sung-Jin;Moon, Hae-Won;An, In-Young
    • Animal Systematics, Evolution and Diversity
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    • v.28 no.2
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    • pp.84-96
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    • 2012
  • Some gorgonians in the families, Primnoidae and Isididae within the suborder Calcaxonia were collected from subtidal zones between depths of 10 and 45 m in the coastal regions of King Sejong Station ($62^{\circ}13'S$, $058^{\circ}47'W$), Korea Polar Research Institute of Korea Ocean Research and Development Institute (KORDI) by SCUBA diving from 2009 to 2011. Three species in the Primnoidae, $Arntzia$ $gracilis$ (Molander, 1929), $Thouarella$ ($Thouarella$) $antarctica$ (Valenciennes, 1846) and $Onogorgia$ $nodosa$ (Molander, 1929), and also one species in the family Isididae, $Tenuisis$ $microspiculata$ (Molander, 1929) are newly recorded to octocorallian fauna in Marian Cove and Potter Cove of King George Island. These four species have been described in detail.

Determination of Rare Earth Elements Abundance in Alkaline Rocks by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) (ICP-MS를 이용한 알칼리암의 희토류원소 정량분석)

  • Hur, Soon-Do;Lee, Jong-Ik;Lee, Mi-Jung;Kim, Yea-Dong
    • Ocean and Polar Research
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    • v.25 no.1
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    • pp.53-62
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    • 2003
  • Inductively coupled plasma mass spectrometry (ICP-MS) is useful instrument for determining abundance of rare earth elements, due to very low detection limits and rapid data acquisition. In this article, two methods are used for decomposition of alkaline rocks; close vessel acid digestion and $Na_2Co_3$ fusion. The two analytical results show good agreements. Considering total dissolved solids and detection limits, the most adequate dilution factor is 5,000 times. Polyatomic ion interferences during analysis can give rise to Inaccuracies. After correction from oxide and hydroxide interference, the analytical result show 20-30% decrease for Gd and Tm, 10-20% decrease for Tb and Er. In comparing the analytical results from KORDI with other institutes, most rare earth elements abundance show good agreements except Lu.

Effect of conjugation of mesogenic core of nematic liquid crystals for polar anchoring strength on rubbed polyimide surfaces (극각 방향의 결합강도에 관한 네마틱 액정의 분자구조 변화의 효과)

  • 서대식
    • Electrical & Electronic Materials
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    • v.9 no.3
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    • pp.265-269
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    • 1996
  • We have studied the effect of the mesogenic core of nematic liquid crystals (NLCs) for polar (out-of-plane tilt) anchoring strength and surface order parameter on rubbed polyimide (PI) surfaces. The order of polar anchoring strength for NLCs on rubbed PI surfaces is 5CB > PCH5 > CCH5. From the above results, we suggest that the polar anchoring strength depends on the polarizability of the NLCs. The surface order parameter for NLCs is 5CB > PCH5 > CCH5 on rubbed PI surfaces. We conclude that the polar anchoring strength is strongly related to the surface order parameter on rubbed PI surfaces.

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