• Title/Summary/Keyword: 동공

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Iris Recognition using Gabor Wavelet and Fuzzy LDA Method (가버 웨이블릿과 퍼지 선형 판별분석 기법을 이용한 홍채 인식)

  • Go Hyoun-Joo;Kwon Mann-Jun;Chun Myung-Geun
    • Journal of KIISE:Software and Applications
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    • v.32 no.11
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    • pp.1147-1155
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    • 2005
  • This paper deals with Iris recognition as one of biometric techniques which is applied to identify a person using his/her behavior or congenital characteristics. The Iris of a human eye has a texture that is unique and time invariant for each individual. First, we obtain the feature vector from the 2D Iris pattern having a property of size invariant and using the fuzzy LDA which is further through four types of 2D Gabor wavelet. At the recognition process, we compute the similarity measure based on the correlation values. Here, since we use four different matching values obtained from four different directional Gabor wavelet and select the maximum value, it is possible to minimize the recognition error rate. To show the usefulness of the proposed algorithm, we applied it to a biometric database consisting of 300 Iris Patterns extracted from 50 subjects and finally got more higher than $90\%$ recognition rate.

Super Multi-view Display Method using Pin-hole Array (핀홀어레이를 이용한 슈퍼 멀티-뷰 3D 디스플레이)

  • Byeon, Jin-A;Kwon, Ki-Chul;Erdenebat, Munkh-Uchral;Park, Jae-Hyeung;Kim, Sung-Kyu;Kim, Jong-Jae;Kim, Nam
    • Korean Journal of Optics and Photonics
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    • v.25 no.1
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    • pp.21-28
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    • 2014
  • In this paper a Super Multi-view display method using a pinhole array with full parallax was proposed. The proposed method was simulated and its parameters analyzed. Also, the distribution and irradiance of light through each pinhole on the retina receiver, according to the change of crystalline lens focal length, were found by simulation. As a result, an image free of blurring was obtained while the crystalline lens focused on the depth plane of the three-dimensional image created by the imaging lens.

Spinal Syringomyelia Secondary to an Intracranial Microcystic Meningioma in a Dog (개에서 척수공동증을 동반한 소낭성 뇌수막종 1례)

  • Won, Sangcheol;Kim, Jae-Hoon
    • Journal of Veterinary Clinics
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    • v.31 no.5
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    • pp.439-444
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    • 2014
  • A 5-year-old, 2.7 kg female maltese dog was presented a local veterinary clinic with one week history of hindlimb lameness associated with patellar luxation. Reduction of bilateral medial patellar luxation was operated using trochlear resection and lateral reinforcement technique. Three weeks after the surgery, the dog showed bending spine with pain in thoracic and lumbar region, continuous ataxia and intermittent convulsion. Magnetic resonance imaging scanning revealed a hyperintense mass in right frontal lobe of brain and abnormal cavitation from cervical cord to third lumbar cord. Histopathologically, neoplasm in brain composed of meningothelial cells showed loosely reticular or lace-like morphology with numerous extracellular cystic spaces of variable size and shape. Neoplastic cells were positive for vimentin and negative for neuron specific enolase and glial fibrillary acidic protein. Irregular shaped enlarge central canal-like cavity was existed in cervical and lumbar cords. In our best knowledge, this report described the clinical findings, imaging and histopathologic characteristics of unusual intracranial microcystic meningioma with secondary syringomyelia in a dog.

The Influence of the Stiles - Crawford Effect on the Image (Stiles - Crawford 효과가 결상에 미치는 영향)

  • Park, Seong Jong
    • Journal of Korean Ophthalmic Optics Society
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    • v.5 no.2
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    • pp.175-180
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    • 2000
  • The intensity of beam of light entering near the pupil edge is less than when it passes through the center of the pupil, this phenomenon is known as the Stiles-Crawford effect. In this paper, we investigate the variation in the shape of confusion circle when the real amplitude distribution of incident beam in pupil area is shifted to any direction by effects. The shape of confusion circle on the image surface is rotational symmetric when the real amplitude distribution of incident beam in pupil area isn't shifted, and the shape of confusion circle on the image surface is asymmetric as ellipse when the real amplitude distribution of incident beam in pupil area is shifted. The shifted direction of the real amplitude distribution of incident beam in pupil area equals the major axis direction of confusion circle on the image surface. When the shifted direction of the real amplitude distribution of incident beam in pupil area changes from ${\Delta}{\phi}$ to ${\Delta}{\phi}+{\pi}$, the intensity distributions and the shapes of confusion circle on the image surface for ${\Delta}{\phi}$ equals that for ${\Delta}{\phi}+{\pi}$. We know from above results that the influences of ${\Delta}{\phi}+{\pi}$ and ${\Delta}{\phi}+{\pi}$ cases on the image quality of optical system equal.

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Morphable Model to Interpolate Difference between Number of Pixels and Number of Vertices (픽셀 수와 정점들 간의 차이를 보완하는 Morphable 모델)

  • Ko, Bang-Hyun;Moon, Hyeon-Joon;Kim, Yong-Guk;Moon, Seung-Bin;Lee, Jong-Weon
    • The Journal of the Korea Contents Association
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    • v.7 no.3
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    • pp.1-8
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    • 2007
  • The images, which were acquired from various systems such as CCTV and Robot, include many human faces. Because of a rapid increase in visual data, we cannot process these manually; rather we need to do these automatically. Furthermore, companies require automatic security systems to protect their new technology. There are various options available to us, including face recognition, iris recognition and fingerprint recognition. Face recognition is preferable since it does not require direct contact. However, the standard 2-Dimensional method is limited, so Morphable Models may be recommended as an alternative. The original morphable model, made by MPI, contains a large quantity of data such as texture and geometry data. This paper presents a Geometrix-based morphable model designed to reduce this data capacity.

Iris Recognition Using the 2-D Gabor Filter (2-D Gabor 필터를 이용한 홍채인식)

  • Go, Hyoun-Joo;Lee, Dae-Jong;Chun, Myung-Geun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.13 no.6
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    • pp.716-721
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    • 2003
  • This paper deals with the iris recognition as one of biometric techniques which are applied to identify a person using his/her behavior or congenital characteristics. The iris of a human eye has a texture that is unique and time invariant for each individual. First, we obtain the feature vector from the 2D iris pattern having a property of size invariant and divide it into 24 sectors which are further through three types of 2D Gabor filters. At the recognition process, we compute the similarity measure based on the correlation values. Here, since we use three different matching values obtained from three different directional Gabor filters and select the maximum value among them, it is possible to minimize the recognition error rate. To show the usefulness of the proposed algorithm, we applied it to a biometric database consisting of 50 iris patterns extracted from 10 subjects and finally get more higher than 90% recognition rate.

Host-Guest Interactions of Cyclic and Acyclic Polyethers with Alkylammonium Ions (고리 및 비고리 폴리에테르와 알킬암모늄 이온과의 호스트-게스트 상호작용)

  • Jeong, Jong Hwa;Kim, Dae Yeon;Lee, Sim Seong
    • Journal of the Korean Chemical Society
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    • v.38 no.7
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    • pp.509-515
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    • 1994
  • The interactions of 11 kinds of primary and secondary alkylammonium ions with cyclic (12C4, 15C5, 18C6, DT18C6 and DA18C6) and acyclic$(Q_2O_5)$ polyethers were investigated by NMR titration and conductometry. All of the alkylammonium ions under investigation form the relatively stable 1 : 1 complexes with crown ethers and acyclic polyether by H-bond. The interactions of alkylammonium ions with analogeous hosts having different size were in the order of 18C6 > 15C5 > 12C4, and the strengthes of donor atoms toward the alkylammonium ions were in the order of N > O > S. 18C6 forms more favorable interactions with primary alkylammonium ions than secondary alkylammonium ions, otherwise DA18C6 shows the opposite behaviors. The stability constants for complexations of 18C6 with the alkylammonium ions were determined conductometrically in methanol at 25$^{\circ}C$. The major factors affecting the stability of complexes were the type of alkylammonium ions, the length of alkyl-chain and the steric hindrance due to the structure of alkyl groups on complexation.

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77 GHz Waveguide VCO for Anti-collision Radar Applications (차량 충돌 방지 레이더 시스템 응용을 위한 77 GHz 도파관 전압 조정 발진기)

  • Ryu, Keun-Kwan;Kim, Sung-Chan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.7
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    • pp.1652-1656
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    • 2014
  • In this work, we demonstrated a 77 GHz waveguide VCO with transition from WR-12 to WR-10 for anti-collision radar applications. The fabricated waveguide VCO consists of a GaAs-based Gunn diode, a varactor diode, a waveguide transition, and two bias posts for operating as a LPF and a resonator. The cavity is designed for fundamental mode at 38.5 GHz and operated at second hormonic of 77 GHz. The waveguide transition has a 1.86 dB of insertion loss and -30.22 dB of S11 at the center frequency of 77 GHz. The fabricated VCO achieves an oscillation bandwidth of 870 MHz. Output power is from 12.0 to 13.75 dBm and phase noise is -100.78 dBc/Hz at 1 MHz offset frequency from the carrier.

Studies on the Structure of Forest Community at Turobong-Sangwangbong Area in Odaesan National Park - Abies nephrolepis and Taxus cuspidata Forest - (오대산 국립공원 두노봉-상왕봉 지역의 삼림군집구조에 관한 연구 - 분비나무림과 주목림 -)

  • 김갑태;엄태원;추갑철
    • Korean Journal of Environment and Ecology
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    • v.10 no.1
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    • pp.160-168
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    • 1996
  • To investigate the structure and the conservation strategy of natural forest at Turobong-Sangwangbong area in Odaesan, 19 plots(10*10m) were set up with random sampling method. Several characteristics - needle injury, rate of fallen needle, stem injury, shoot and twig, apical dominance, tree form- of Abies nephrolepis and Tavus cuspidata were investigated with checklist. Two groups(Taxus cuspidata community and Quercus mongolica-Betula ermanii community) were classified by cluster analysis. High positive correlations were prover between Taxus cuspidata and Tripterygium regelii, Sorbus commixta; Quercus mongolica and Euonymus sieboldianus. High negative correlations were proved between Taxus cuspidata and Abies nephrolepis, Quercus mongolica and Betula ermanii; Abies nephrolepis and Trioterygum regelii. Species diversity(H') of investigated area was 0.9608-1.24990. Mean score of Abies nephrolepis was calculated at 6.1 point and ratio of dead individuals was 10.9%. Mean score of Taxus cuspidata was calculated at 17.3 point. Injury of Taxus cuspieata was classified three types, such as branch dieback, wound cavity on the stem and crooked stem.

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A Study on the Growing State of Taxus cuspidata in Baekwoonsan the High 1 Ski Slope Construction Area in Jeungsun-gun, Gangwon-do (강원도 정선군 백운산 High 1 스키장 슬로프 개발 지역의 주목 생육현황 조사)

  • Kim, Gab-Tae;Um, Tae-Won;Kim, Hoi-Jin
    • Korean Journal of Environment and Ecology
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    • v.23 no.4
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    • pp.302-308
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    • 2009
  • For the proper tree management of Taxus cuspidata, distributed in the High 1 Ski Slope construction area in Baekwoonsan, Jeungsun-gun, Kangwon-do, the growing states of 323 trees(including transplanted 57trees) are investigated. Tree height, rootcollar diameter, D.B.H., stem condition, apical shoot, dead branch, needle growth condition, 2-year-old needle loss, root condition, tree form are investigated. Taxus cuspidata are mainly growing at the sites, high elevated mountain ridge or slopes facing north. Growing states of Taxus cuspidata, distributed in Baekwoonsan are relatively better than those of Taxus cuspidata and Abies koreana at other subalpine zone in Korea. Damaged trees are mainly due to root-removal through transplanting, root-damages by raising the ground level and digging. Several methods of Taxus cuspidata conservation were suggested.