• Title/Summary/Keyword: Pupil Size

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Optical Performance Analysis of the Eye which it Follows in Iris Eccentricity (홍채 편심에 따른 눈의 광학적 성능 분석)

  • Kim, Bong-Hwan;Han, Sun-Hee
    • Journal of Korean Ophthalmic Optics Society
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    • v.14 no.2
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    • pp.31-34
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    • 2009
  • Purpose: We are to analyze optically how to affect the eye related with movement of the iris. Methods: Using the schematic eye to have the crystalline lens of the radial GRIN and the spherical GRIN forms that come to be planned in existing, the iris centre was moved 0.5 mm with nasal direction in order to be identical with the real eye. Also, considering that the iris centre move according to increase of the pupil size, the iris centre was moved 0.4 mm with temporal direction to analyze the optical performance change of the eye respectively. Results: Because of decrease in the spherical aberration, the schematic eye with nasal direction 0.5 mm eccentricity of the iris showed a different consequence plentifully compared with the performance of the real eye. Besides, the schematic eye with temporal direction 0.4 mm eccentricity of the iris showed that the spherical aberration somewhat increased. Conclusions: In case of design of the schematic eye with the similar real eye performance which the iris centre was moved 0.5 mm with nasal direction, we need to research about aspheric coefficient of optical constants of each refracting surface considering the performance change of a spherical aberration, a peripheral power error and astigmatism etc, owing to change of the real eye hence to be affected by the iris movement.

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A Study on Iris Image Restoration Based on Focus Value of Iris Image (홍채 영상 초점 값에 기반한 홍채 영상 복원 연구)

  • Kang Byung-Jun;Park Kang-Ryoung
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.43 no.2 s.308
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    • pp.30-39
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    • 2006
  • Iris recognition is that identifies a user based on the unique iris texture patterns which has the functionalities of dilating or contracting pupil region. Iris recognition systems extract the iris pattern in iris image captured by iris recognition camera. Therefore performance of iris recognition is affected by the quality of iris image which includes iris pattern. If iris image is blurred, iris pattern is transformed. It causes FRR(False Rejection Error) to be increased. Optical defocusing is the main factor to make blurred iris images. In conventional iris recognition camera, they use two kinds of focusing methods such as lilted and auto-focusing method. In case of fixed focusing method, the users should repeatedly align their eyes in DOF(Depth of Field), while the iris recognition system acquires good focused is image. Therefore it can give much inconvenience to the users. In case of auto-focusing method, the iris recognition camera moves focus lens with auto-focusing algorithm for capturing the best focused image. However, that needs additional H/W equipment such as distance measuring sensor between users and camera lens, and motor to move focus lens. Therefore the size and cost of iris recognition camera are increased and this kind of camera cannot be used for small sized mobile device. To overcome those problems, we propose method to increase DOF by iris image restoration algorithm based on focus value of iris image. When we tested our proposed algorithm with BM-ET100 made by Panasonic, we could increase operation range from 48-53cm to 46-56cm.

Determination Factors Affecting the High Order Aberrations in Preoperative and Postoperative LASEK (라섹 수술 전과 후의 고위수차에 영향을 미치는 결정변수)

  • Kim, Tae-Heung;Lee, Hyun;Rhee, Kang-Oh;Lee, Tae-Yong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.9
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    • pp.5621-5627
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    • 2014
  • To specify the standard of LASEK surgery, this study examined the determination factors affecting the high order aberrations (HOAs) in preoperative and postoperative LASEK. 51 adult patients (102 eyes) were evaluated at the baseline and 2 months after LASEK surgery from Nov 2011 to Jul 2012. The postoperative HOAs ($0.538{\mu}m$) were higher than the preoperative ($0.341{\mu}m$). In linear regression analysis, the refractive components that affected the postoperative HOAs were $J_0$ of corneal astigmatism (CA, 0.400), $J_0$ of refractive astigmatism (RA, 0.389), corneal astigmatism (CA, 0.282), spherical equivalent (SE, 0.239), refractive astigmatism (RA, 0.213), and pupil size (PS, 0.194) with a high R. In multiple regression, $J_0$ of CA, PS and SE were significant factors with the postoperative HOAs. In conclusion, both HOAs and $J_0$ of CA should be considered when determining the suitable factors for LASEK surgery.

Comparison of Severity in Organophosphate Insecticide Poisoning Patients Treated with Tracheostomy (기관절개술을 시행한 유기인계 살충제 중독 환자의 중증도 비교)

  • Choo, Dae-Hyuk;Park, Yong-Jin;Kim, Sun-Pyo;Kim, Seog-Jung;Cho, Soo-Hyung;Cho, Nam-Soo
    • Journal of The Korean Society of Clinical Toxicology
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    • v.9 no.2
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    • pp.61-70
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    • 2011
  • Purpose: This study investigated the effect on survival rate for organophosphate intoxication patients who received trachostomy. This research was conducted to help identify appropriate treatment of patients who received a trachostomy. Methods: This research was retrospectively conducted using the medical records of 141 patients who arrived at the Chosun University Hospital emergency medical center between Jan 2007 and Dec 2010, suffering from organophosphate intoxication. They were placed in two groups including one which received trachostomy as part of their treatment and one that did not. The effect of each variable on mortality was evaluated by regressionanalysis. Results: Of 141 patients with organophosphate intoxication, 105 of them did not tracheostomy and 16 were dead cohorts (15.2%). Their size of pupil was 1mm. Factors such as amount of organophosphate ingested, PAM time after ingestion, average body temperature, arrival time, atropinization time after ingestion, AST/ALT, Bun/Cr all appeared to be significant factors in death cohorts (P<0.05). 36 patients among the total had tracheostomy and 11 ones of them were in dead cohort (30.6%) and their average age was 58 years. The facts affect the state of patients in dead cohort include the amount of intoxication which between $327.27{\pm}194.1ml$, performing intubation 686 mins after intubation, reaching to the hospital after 580mins, injecting PAM 744 mins after intoxication, injecting atropine 627 mins after intoxication. The largest cases of patient's state was found to be stupor with 14 patients (38.9%) the level of Cholinesterase in blood appeared to be significant in dead cohort as $391.00{\pm}353.9IU/L$ (P<0.05). Conclusion: Further planned studies are necessary on the use of tracheostomy for treatment of poisoning victims, especially those intoxicated by organophosphorus insecticides.

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IGRINS Design and Performance Report

  • Park, Chan;Jaffe, Daniel T.;Yuk, In-Soo;Chun, Moo-Young;Pak, Soojong;Kim, Kang-Min;Pavel, Michael;Lee, Hanshin;Oh, Heeyoung;Jeong, Ueejeong;Sim, Chae Kyung;Lee, Hye-In;Le, Huynh Anh Nguyen;Strubhar, Joseph;Gully-Santiago, Michael;Oh, Jae Sok;Cha, Sang-Mok;Moon, Bongkon;Park, Kwijong;Brooks, Cynthia;Ko, Kyeongyeon;Han, Jeong-Yeol;Nah, Jakyuong;Hill, Peter C.;Lee, Sungho;Barnes, Stuart;Yu, Young Sam;Kaplan, Kyle;Mace, Gregory;Kim, Hwihyun;Lee, Jae-Joon;Hwang, Narae;Kang, Wonseok;Park, Byeong-Gon
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.2
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    • pp.90-90
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    • 2014
  • The Immersion Grating Infrared Spectrometer (IGRINS) is the first astronomical spectrograph that uses a silicon immersion grating as its dispersive element. IGRINS fully covers the H and K band atmospheric transmission windows in a single exposure. It is a compact high-resolution cross-dispersion spectrometer whose resolving power R is 40,000. An individual volume phase holographic grating serves as a secondary dispersing element for each of the H and K spectrograph arms. On the 2.7m Harlan J. Smith telescope at the McDonald Observatory, the slit size is $1^{{\prime}{\prime}}{\times}15^{{\prime}{\prime}}$. IGRINS has a plate scale of 0.27" pixel-1 on a $2048{\times}2048$ pixel Teledyne Scientific & Imaging HAWAII-2RG detector with a SIDECAR ASIC cryogenic controller. The instrument includes four subsystems; a calibration unit, an input relay optics module, a slit-viewing camera, and nearly identical H and K spectrograph modules. The use of a silicon immersion grating and a compact white pupil design allows the spectrograph collimated beam size to be 25mm, which permits the entire cryogenic system to be contained in a moderately sized ($0.96m{\times}0.6m{\times}0.38m$) rectangular Dewar. The fabrication and assembly of the optical and mechanical components were completed in 2013. From January to July of this year, we completed the system optical alignment and carried out commissioning observations on three runs to improve the efficiency of the instrument software and hardware. We describe the major design characteristics of the instrument including the system requirements and the technical strategy to meet them. We also present the instrumental performance test results derived from the commissioning runs at the McDonald Observatory.

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A Study on Facial Expression Acting in Genre Drama - with Focus on K-Drama Voice2 - (장르 드라마에서의 표정연기연구 - 드라마 '보이스2'를 중심으로 -)

  • Oh, Youn-Hong
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.8
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    • pp.313-323
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    • 2019
  • For the actors on video, facial expression acting can easily become 'forced facial expression' or 'over-acting'. Also, if self-restraint is emphasized too much, then it becomes 'flat acting' with insufficient emotions. By bringing forth questions in regard to such facial expression acting methods, this study analyzed the facial expression acting of the actors in genre dramas with strong commercial aspects. In conclusion, the facial expression acting methods of the actors in genre dramas were being conducted in a typical way. This means that in visual conventions of video acting, the aesthetic standard has become the important standard in the facial expression acting of the actors. In genre dramas, the emotions of the characters are often revealed in close-up shots. Within the close-up shot, the most important expressive medium in a 'zoomed-in face' is the 'pupil of the eye', and emotions are mostly expressed through the movements of the eye and muscles around it. The second most important expressive medium is the 'mouth'. The differences in the degree of opening and closing the mouth convey diverse emotions along with the expression of the 'eye'. In addition, tensions in the facial muscles greatly hinder the expression of emotions, and the movement of facial muscles must be minimized to prevent excessive wrinkles from forming on the surface of the face. Facial expressions are not completed just with the movement of the muscles. Ultimately, the movement of the muscle is the result of emotions. Facial expression acting takes place after having emotional feelings. For this, the actor needs to go through the process of 'personalization' of a character, such as 'emotional memory', 'concentration' and 'relaxation' which are psychological acting techniques of Stanislavsky. Also, the characteristics of close-up shots that visually reveal the 'inner world' should be recognized. In addition, it was discovered that the facial expression acting is the reaction acting that provides the important point in the unfolding of narratives, and that the method of facial expression and the size of the shots required for the actors are different depending on the roles of main and supporting characters.