• Title/Summary/Keyword: iris features

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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.

Detecting and Tracking Vehicles at Local Region by using Segmented Regions Information (분할 영역 정보를 이용한 국부 영역에서 차량 검지 및 추적)

  • Lee, Dae-Ho;Park, Young-Tae
    • Journal of KIISE:Software and Applications
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    • v.34 no.10
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    • pp.929-936
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    • 2007
  • The novel vision-based scheme for real-time extracting traffic parameters is proposed in this paper. Detecting and tracking of vehicle is processed at local region installed by operator. Local region is divided to segmented regions by edge and frame difference, and the segmented regions are classified into vehicle, road, shadow and headlight by statistical and geometrical features. Vehicle is detected by the result of the classification. Traffic parameters such as velocity, length, occupancy and distance are estimated by tracking using template matching at local region. Because background image are not used, it is possible to utilize under various conditions such as weather, time slots and locations. It is performed well with 90.16% detection rate in various databases. If direction, angle and iris are fitted to operating conditions, we are looking forward to using as the core of traffic monitoring systems.

Comparison of Anterior Segment Features between Groups with or without Glaucoma in Pseudoexfoliation Syndrome (거짓비늘증후군에서 개방각녹내장 병합 유무에 따른 전안부 소견과 생체 계측치에 대한 비교)

  • Gu, Bon Hyeok;Choi, Sangkyung
    • Journal of The Korean Ophthalmological Society
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    • v.59 no.11
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    • pp.1049-1055
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    • 2018
  • Purpose: To investigate the factors associated with glaucoma in patients with pseudoexfoliation syndrome by comparing features of the anterior segments and ocular biometry according to the presence or absence of open-angle glaucoma in pseudoexfoliation syndrome. Methods: We analyzed 96 patients (115 eyes) diagnosed as having pseudoexfoliation syndrome in this study. The patients were divided into two groups of simple pseudoexfoliation syndrome (64 patients, 76 eyes) and pseudoexfoliation glaucoma (32 patients, 39 eyes). We compared the age, sex, underlying disease, location of pseudoexfoliative material, iris change, degree of nuclear cataract, pupil dilatation, corneal endothelial cell counts, central corneal thickness, anterior chamber depth, axial length, corneal curvature, and intraocular pressure (IOP). Results: There were no significant differences between the two groups in terms of age (p = 0.694), sex (p = 0.161), diabetes (p = 0.440), hypertension (p = 0.238), pseudoexfoliative material observed in anterior capsule (p = 0.700), pupillary margin (p = 0.210), iris depigmentation (p = 0.526), pupillary ruff loss (p = 0.708), degree of nuclear cataract (p = 0.617), pupil dilatation (p = 0.526), central corneal thickness (p = 0.097), anterior chamber depth (p = 0.283), axial length (p = 0.095), or horizontal and vertical corneal curvature (p = 0.066 and 0.306, respectively). In pseudoexfoliation glaucoma, significantly higher IOP (p = 0.026), a high frequency of membrane formation (p = 0.047), and decreased corneal endothelial cell counts (p = 0.048) were observed. Conclusions: Pseudoexfoliation syndrome with open-angle glaucoma was shown to be associated with high IOP, decreased corneal endothelial cell counts, and a high frequency of membrane formation. Therefore, when such changes are observed in pseudoexfoliation syndrome patients, a higher risk of open-angle glaucoma should be recognized, and careful attentionis required accordingly.

Dental anomalies associated with Axenfeld-Rieger syndrome (Axenfeld-Rieger 증후군과 연관된 치과적 이상)

  • Kim, Ki-Rim;Lee, Doo-Young;Kim, Seung-Hye;Lee, Sang-Hui;Choi, Byung-Jai;Lee, Jae-Ho
    • The Journal of Korea Assosiation for Disability and Oral Health
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    • v.6 no.2
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    • pp.94-98
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    • 2010
  • Axenfeld-Rieger syndrome is a rare autosomal dominant disorder characterized by various ocular and extraocular malformations. The incidence of Axenfeld-Rieger syndrome has been estimated to be 1 per 200,000. The syndrome is characterized by short body stature, delayed bone age, and deficient or arrested development of neural crest cells involving the anterior chamber of the eyes, facial bones, teeth, periumbilical skin, and cardiovascular system. This is a case of a 6 year-old girl, who came to the department of the pediatric dentistry, Yonsei University Dental Hospital, for evaluation and treatment of multiple congenital missing permanent teeth. The patient presented typical dental, craniofacial, and systemic features of Axenfeld-Rieger syndrome, such as glaucoma, oval pupil, heterochromatic iris, umbilical hernia, and delayed bone age. On the panoramic view, 3 primary teeth were missing and 13 permanent tooth germs were absent. On the lateral cephalograph, underdevelopment of the maxilla and normal growth pattern of the mandible were confirmed. Periodic dental follow-up is planned for evaluation and interceptive treatment of her dental and craniofacial problems. Denture or removable space maintainer with a pontic is considered for esthetic and functional restoration. In addition, orthognathic surgery is also planned in future to prevent further midfacial skeletal deformation. Early diagnosis of Axenfeld-Rieger syndrome is very important to prevent exacerbation of complications, such as glaucoma and skeletal deformities.

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Crustal Structure Beneath Korea Seismic Stations (Inchon, Wonju and Pohang) Using Receiver function (수신함수에 의한 한국 지진관측소(인천, 원주 포항) 하부의 지각구조 연구)

  • Kim, So-Gu;Lee, Seung-Kyu
    • Journal of the Korean Society of Hazard Mitigation
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    • v.4 no.4 s.15
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    • pp.43-54
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    • 2004
  • The broadband receiver functions are developed from teleseismic P waveforms recorded at Wonju(KSRS), Inchon(IRIS), and Pohang(PHN), and are analyzed to examine the crustal structure beneath these stations. The teleseismic receiver functions are inverted in the time domain of the vertical P wave velocity structures beneath the stations. Clear P-to-S converted phases from the Moho interface are observed in teleseismic seismograms recorded at these stations. The crustal velocity structures beneath the stations are estimated by using the receiver function inversion method(Ammon et al., 1990). The general features of inversion results are as follows: (1) For the Inchon station, the Conrad discontinuity exists at 17.5 Km(SW) deep and the Moho discontinuity exists at 29.5 Km(NW) and 30.5 Km(SE, SW) deep. (2) The shallow crustal structure beneath Wonju station may be covered with a sedimentary rock of a 3 Km thickness. The average Moho depth is assumed about 33.0 Km, and the Conrad discontinuity may exist at 17.0 Km(NE) and 21.0 Km(NW) deep. (3) For Pohang station, the thickness of shallow sedimentary layer is a 3.0 Km in the direction of NE and NW. The Moho depth is 28.0 Km in the direction of the NE and NW. The Conrad discontinuity can be estimated to be existed at 21.0 Km deep for the NE and NW directions.

AXENFELD-RIEGER SYNDROME WITH DENTAL PROBLEM : A CASE REPORT (Axenfeld-Rieger Syndrome 환자의 증례보고)

  • Seong, Min-Kyoung;Shin, Teo-Jeon;Kim, Young-Jae;Kim, Jung-Wook;Jang, Ki-Taeg;Lee, Sang-Hoon;Kim, Chong-Chul;Hyun, Hong-Keun
    • The Journal of Korea Assosiation for Disability and Oral Health
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    • v.8 no.2
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    • pp.113-117
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    • 2012
  • Axenfeld-Rieger syndrome (ARS) is a rare disorder with variable morphology characterized by malformations of the anterior segment of the eye such as iris hypoplasia, iridocorneal adhesions, corectopia and polycoria. Craniofacial and dental anomalies are also regularly reported in connection with ARS. Dental features include hypodontia in primary and permanent dentition, microdontia, short roots and abnormally shaped teeth. The patient in this case is a 14-year-old girl who has visited Seoul National Dental Hospital in 2002 for the first time. A panorama was taken on the day of her first visit, and total absence of maxillary anterior dentition and mandibular premolars were observed. The patient was on a treatment schedule by the department of ophthalmology at Seoul National Hospital for a morphological dyplasia of the pupil and she was diagnosed with ARS. Periodic panoramic observations were performed followingly, and she was finally diagnosed of congenital missing of maxillary anteriors and mandibular second premolars. In 2009, composite resin build-ups of maxillary primary central incisors were performed, and she has been on her regular follow-ups until now.

Implementation and Evaluation of ECG Authentication System Using Wearable Device (웨어러블 디바이스를 활용한 ECG 인증 시스템 구현 및 평가)

  • Heo, Jae-Wook;Jin, Sun-Woo;Jun, Moon-Seog
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.10
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    • pp.1-6
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    • 2019
  • As mobile technologies such as Internet of Things (IoT)-based smart homes and financial technologies (FinTech) are developed, authentication by smart devices is used everywhere. As a result, presence-based biometric authentication using smart devices has become a new mainstream in knowledge-based authentication methods like the existing passwords. The electrocardiogram (ECG) is less prone to forgery, and high-level personal identification is its unique feature from among various biometric authentication methods, such as the pulse, fingerprints, the face, and the iris. Biometric authentication using an ECG is receiving a great deal of attention due to its uses in healthcare and FinTech. In this study, we implemented an ECG authentication system that allows users to easily measure and authenticate their ECG waveforms using a miniaturized wearable device, rather than a large and expensive measurement device. The implemented ECG authentication system identifies ECG features through P-Q-R-S-T feature point identification, and was user-certified under the proposed authentication protocols. Finally, assessment of measurements in a majority of adult males showed a relatively low false acceptance rate of 1.73%, and a low false rejection rate of 4.14%, in a stable normal state. In a high-activity state, the false acceptance rate was 13.72%, and the false rejection rate was 21.68%. In a high-heart rate state, the false acceptance rate was 10.48%, and the false rejection rate was 11.21%.