• Title/Summary/Keyword: iris

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Zoom Lens Calibration for a Video Measuring System (컴퓨터 비젼을 이용한 정밀 측정 장비의 줌 렌즈 캘리브레이션)

  • Hahn, Kwang-Soo;Choi, Joon-Soo;Choi, Ki-Won
    • Journal of Internet Computing and Services
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    • v.6 no.5
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    • pp.57-71
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    • 2005
  • Precise visual measurement applications, like video measuring system (VMS), use camera systems with motorized zoom lens for fast and efficient measurement. In this paper, we introduce an efficient calibration method for zoom lens of VMS controlled by servo motor. For the automated zoom lens calibration of the VMS, only zoom lens setting needs to be calibrated and parameters calibrated by zoom lens settings are image center and pixel size changed by zoom levels, The extrinsic parameters, like focus and iris, do not need to be calibrated since the parameters are usually fixed, It needs a lot of time and effort to calibrate the camera for ali the different zoom levels. In this paper, we also propose an efficient and fast zoom lens calibration method, which calculates the calibration parameters of the zoom lens settings for the minimum number of zoom levels and estimates other parameters for the uncalculated zoom levels using the interpolation of the calculated parameter values.

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A Case of Type 1 Neurofibromatosis Associated with Multiple Metastatic Gastrointestinal Stromal Tumors (다발전이성 위장관 간질종양을 동반한 제 1형 신경섬유종증 1예)

  • Jang, Hyo Jin;Koh, Sung Ae;Jeong, Da Eun;Jung, Ji Yoon;Goo, Eun Ju;Lee, Kyoung Hee;Choi, Joon Hyuk;Hyun, Myung Soo
    • Journal of Yeungnam Medical Science
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    • v.30 no.2
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    • pp.105-108
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    • 2013
  • Type 1 neurofibromatosis (von Recklinghausen's disease, NF-1) is an autosomal-dominant neurocutaneous-disorder characterized by systemic cafe'-au-lait spots, multiple cutaneous neurofibromas, axillary or inguinal freckling, and Lisch nodules (pigmented iris hamartomas). Approximately 10-25% of NF1 patients have gastrointestinal neoplasms. Gastrointestinal stromal tumor (GIST) in patients with neurofibromatosis is most commonly found in the small bowel and the stomach, and approximately 60% of such patients have multiple tumors or multiple tumor sites. Although, the increased incidence of GIST in patients with neurofibromatosis is well documented in pathology literature in English, but has rarely been documented in Korea. Here, we report a case of multiple GISTs in a 48-year-old woman accompanied by NF1. She was admitted to Yeung-nam University Hospital with complaints of melena and dyspnea. A contrast-enhanced computed tomography (CT) scan revealed that multiple soft tissue masses were occupying the entire peritoneal cavity. An ultrasonogram- guided biopsy was performed and the tumors were found to have been composed of tumor cells that were positive for c-kit protein. The patient was put on Imatinib mesylate treatment, and further follow-up will be carried out.

Analysis and Design of Waveguide Iris Polarizer for Rotation of Polarization Plane (편파면 회전을 위한 도파관 아이리스 편파기 설계 분석)

  • Yang, Doo-Yeong;Lee, Min-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.7
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    • pp.3201-3206
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    • 2012
  • In this paper, the simplified design methodology for rotation of polarization plane using a square waveguide is proposed. In order to optimize the characteristics of $180^{\circ}$ polarizer operating from 14.3GHz to 14.8GHz in Ku-band, the modified mode matching method and piecewise power tower interpolation are applied to the polarizer design. The optimized results show that the frequency bandwidth in VSWR<2 has covered 500MHz in the Ku-band and phase difference between two orthogonal modes $TE_{10}$and $TE_{01}$ is $180^{\circ}{\pm}1^{\circ}$ in the range of 14.3GHz~14.8GHz. The cross polarization loss has obtained below 40dB and the insertion loss has 0.1dB in the passband. Therefore, the proposed polarizer is suitable for practical Ku-band system requiring the low VSWR and compact size.

Health Risk Assessment of Heavy Metals in Fine Particles Collected in Seoul Metropolitan Area (서울북부 지역 미세먼지에 함유된 유해 중금속의 분석 및 건강위해성평가)

  • Park Eun-Jung;Kang Misun;You Dae-Eun;Kim Dae-Seon;Yu Seung-Do;Chung Kyu-Hyuck;Park Kwangsik
    • Environmental Analysis Health and Toxicology
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    • v.20 no.2 s.49
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    • pp.179-186
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    • 2005
  • Particulate materials (PM) less than 10 ${\mu}m$ in diameter are of special interest in air pollution because they are respirable and responsible for the increasing mortality rate of lung cancer and cardiovascular diseases. These particles are often referred to as $PM_{10}$ and they are divided into a coarse fraction and a fine fraction which is also often referred to as $PM_{25}$. In this study, we monitored the TSP, $PM_{10},\;PM_{2.5}$ concentration of ambient air collected in northern part of Seoul in early spring and measured the concentration of heavy metals; Cr, Mn, Zn, As, Cd, and Pb. All the heavy metals were found in the collected particles and the concentrations were variable in the $PM_{10},\;and\;PM_{2.5}$ respectively. The detected concentration ranges were Cr: $ND\~2,889ng/m^3,\;Mn:2.4\~257.9ng/m^3,\;Zn:ND\~353.7ng/m^3,\; As:ND\~22.3ng/m^3,\;Cd:0.1\~2.9ng/m^3,\;and\;Pb:ND\~392.2ng/m^3$ in fine particles. Heavy metal toxicity of the particles were also tested in $H_9C_2$ cell line derived from rat cardiomyocytes. As for the results of health risk assessment calculated by unit risk of IRIS, heavy metals in ambient air of Seoul metropolitan area were found to be responsible for the increase of total excess cancer risk. Among them, chromium (hexavalent) was found to be the most risky in fine particles of ambient air collected in the northern part of Seoul in early spring.

Comparative Performance Evaluations of Eye Detection algorithm (눈 검출 알고리즘에 대한 성능 비교 연구)

  • Gwon, Su-Yeong;Cho, Chul-Woo;Lee, Won-Oh;Lee, Hyeon-Chang;Park, Kang-Ryoung;Lee, Hee-Kyung;Cha, Ji-Hun
    • Journal of Korea Multimedia Society
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    • v.15 no.6
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    • pp.722-730
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    • 2012
  • Recently, eye image information has been widely used for iris recognition or gaze detection in biometrics or human computer interaction. According as long distance camera-based system is increasing for user's convenience, the noises such as eyebrow, forehead and skin areas which can degrade the accuracy of eye detection are included in the captured image. And fast processing speed is also required in this system in addition to the high accuracy of eye detection. So, we compared the most widely used algorithms for eye detection such as AdaBoost eye detection algorithm, adaptive template matching+AdaBoost algorithm, CAMShift+AdaBoost algorithm and rapid eye detection method. And these methods were compared with images including light changes, naive eye and the cases wearing contact lens or eyeglasses in terms of accuracy and processing speed.

Design of a User authentication Protocol Using Face Information (얼굴정보를 이용한 사용자 인증 프로토콜 설계)

  • 지은미
    • Journal of the Korea Computer Industry Society
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    • v.5 no.1
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    • pp.157-166
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    • 2004
  • Consequently substantial research has been done on the development of the bio-metric recognition method as well as technical research in the field of authentication. As a method of bio-metric recognition, personal and unique information such as fingerprints, voice, face, Iris, hand-geometry and vein-pattern are used. The face image system in bio-metric recognition and information authentication reduces the denial response from the users because it is a non-contact system the face image system operates through a PC camera attached to a computer base this makes the system economically viable as well as user friendly. Conversely, the face image system is very sensitive to illumination, hair style and appearance and consequently creates recognition errors easily, therefore we must build a stable authentication system which is not too sensitive to changes in appearance and light. In this study, I proposed user authentication protocol to serve a confidentiality and integrity and to obtain a least Equal Error Rate to minimize the wrong authentication rate when it authenticates the user.

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Contactless Biometric Using Thumb Image (엄지손가락 영상을 이용한 비접촉식 바이오인식)

  • Lim, Naeun;Han, Jae Hyun;Lee, Eui Chul
    • KIPS Transactions on Software and Data Engineering
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    • v.5 no.12
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    • pp.671-676
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    • 2016
  • Recently, according to the limelight of Fintech, simple payment using biometric at smartphone is widely used. In this paper, we propose a new contactless biometric method using thumb image without additional sensors unlike previous biometrics such as fingerprint, iris, and vein recognition. In our method, length, width, and skin texture information are used as features. For that, illumination normalization, skin region segmentation, size normalization and alignment procedures are sequentially performed from the captured thumb image. Then, correlation coefficient is calculated for similarity measurement. To analyze recognition accuracy, genuine and imposter matchings are performed. At result, we confirmed the FAR of 1.68% at the FRR of 1.55%. In here, because the distribution of imposter matching is almost normal distribution, our method has the advantage of low FAR. That is, because 0% FAR can be achieved at the FRR of 15%, the proposed method is enough to 1:1 matching for payment verification.

Face Recognition System Technologies for Authentication System - A Survey (인증시스템을 위한 얼굴인식 기술 : 서베이)

  • Hwang, Yooncheol;Mun, Hyung-Jin;Lee, Jae-Wook
    • Journal of Convergence Society for SMB
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    • v.5 no.3
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    • pp.9-13
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    • 2015
  • With the advance of ICT, the necessity of user authentication to verify the identity of an opponent online not face to face is increasing. The authentication, the basis of the security, is used in various fields. Because ID-based authentication has weaknesses in terms of stability and losses, two or more than two authentication tools are used in the place in which the security is important. Recently, biometric authentication rather than ID, OTP, SMS authentication has been an issue in terms of credibility and efficiency. As the fields applied to current biometric recognition technologies are increasing, the application of the biometric recognition is being used in various fields such as mobile payment system, intelligent CCTV, immigration inspection, and access control. As the biometric recognition, finger print, iris, retina, vein, and face recognition have been studied actively. This study is to inspect the current state of domestic and foreign standardization including understanding of the face recognition and the trend of technology.

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A Case of Portosystemic Shunt in a Domestic Shorthair Cat (한국 집고양이의 문맥전신션트 한 증례)

  • Cho, Eunkwang;Jeong, Ye Chan;Choi, Ul Soo
    • Journal of Veterinary Clinics
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    • v.31 no.4
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    • pp.316-318
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    • 2014
  • A 3-year-old castrated male domestic shorthair cat was presented with a chief complaint of sudden onset of intermittent seizures occurring five times a day. Physical examination revealed the copper colored iris and loss of menace response at both eyes. Abnormalities of blood works and serum chemistry revealed mild erythrocytosis, severe microcytosis, and threefold increase in ALT activity. Additional liver function tests results were increased bile acid and $NH_3$ concentration. Radiographic study revealed multifocal nodules of the liver and an extrahepatic shunt was noted by ultraonography, which was confirmed by computed tomography as multiple extrahepatic shunts. The cat was scheduled for surgery applying an ameloid ring to occlude the shunt gradually. Diazepam and lactulose were instituted to the patient. However, clinical signs worsened despite medical management with shortened interval of seizures and the patient died due to cardiac arrest.

The Antenna Design for Korea SAT-5 Satellite Communication in Ka-band (무궁화 5호 위성통신용 Ka대역 안테나 설계)

  • Kim, Chun-Won;Cheong, Chi-Hyun;Kim, Kun-Woo;Lee, Seong-Jae
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.42 no.1
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    • pp.90-97
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    • 2014
  • In this paper, we have designed the antenna for Korea SAT-5 Satellite Communication which can use Ka band in the earth station. The antenna structure consist of the the dual-offset gregorian reflector that has high gain and efficiency, the corrugated horn that has symmetric radiation patterns and low side lobe levels, the iris polarizer that make circular polarization and the OrthoMode Transducer that separate transmitting and receiving signals. The designed antenna gain is more than 45.7dBi in Tx-band which use LHCP and 42.0dBi in Rx-band which use RHCP. The co-polarized and cross-polarized radiation pattern comply with ITU-R S.580-6 and S.731-1 that are recommended by International Telecommunication Union in the geostationary satellite. The Axial ratio is less than 1.0dB in Tx-band and 1.5dB in Rx-band that meet MIL-STD-188-164A.