• Journal of Korean Ophthalmic Optics Society
• /
• v.18 no.4
• /
• pp.489-493
• /
• 2013

Purpose: This study was to investigate peripheral vision and provide people with macular degeneration with a guideline for eccentric viewing training. Methods: 30 adult subjects with normal vision took part in this study. The lateral area of $20^{\circ}$ eccentricity from the fovea of right eye was only used to measure the physiological summation. The target was sinusoidal vertical gratings within a circular aperture. The critical points in spatial and temporal summation was found to compare each other for 0.7 cpd and 3.0 cpd, respectively. Results: Critical duration and contrast sensitivity for 0.7 cpd were 540 ms and 1.1, and 315 ms and 0.98 for 3.0 cpd respectively. The critical degrees and contrast sensitivity for 0.7 cpd were $11.3^{\circ}$ and 2.8, and $5^{\circ}$ and 2.63 for 3.0 cpd respectively. Conclusions: The critical point in peripheral vision reaches relatively faster than the one in central vision. It is recommended to train the peripheral retina under the lower spatial frequency more frequently for a short time than constantly for a long time.

• Korean Journal of Cognitive Science
• /
• v.31 no.2
• /
• pp.25-54
• /
• 2020

While there is no evidence for parafoveal processing in alphabetic languages such as English and Finnish, there is some evidence that morphological information is processed in syllabic languages like Chinese. Korean writing system, Hangul, would be able to provide morphological preview benefit effects since it is an "alphabetic syllabary" which contains both alphabetic and syllabic features. This study explored morphological parafoveal preview benefit effects during reading Korean using irregular verbs, which have phonological and orthographical differences between fundamental and conjugated forms. In the Experiment, the target word was irregular conjugated form, and there were four preview conditions: identical (e.g. 구워), fundamental form (e.g. 굽다), orthographically related (e.g. 굼다), and unrelated control (e.g. 죨어). In the result of study, identical was shortest and morphological, orthographical, unrelated preview were followed. Moreover, measures of first-pass reading of morphological preview were significantly shorter than those of unrelated control preview. This results support the hypothesis of morphological preview benefit effects in Korean. The implications of the results are discussed.

• Journal of Korean Ophthalmic Optics Society
• /
• v.15 no.2
• /
• pp.151-154
• /
• 2010

Purpose: We investigated how the movement of iris and visual axis affects the finite schematic eye Methods: Using the schematic eye with the crystalline lens in the existing forms of the radial GRIN and the spherical GRIN, the iris centre was moved 0.5 mm in nasal direction and visual axis was tilted $5^{\circ}$ in same direction, with the additional degree of 2.5 down to locate the focal point in fovea. This study analyzed performance change of the optical system, designing it same as the real eye. Results: The whole aberration distribution showed a considerable difference in performance in comparison with the real eye; the biggest difference shown at the central field of optical system. The spherical aberration showed the biggest difference, and a peripheral power error and field curvature leaned toward (+) direction in aberration distribution. Conclusions: When designing the schematic eye with the performance similar with that of the real eye by taking into consideration the iris centre and visual axis, the aberration at the center field of optical system in particular should be corrected. Spherical aberration which showed the biggest difference should be corrected in the first place. In addition, a peripheral power error and field curvature that leaned toward (+) direction should be moved toward (-) direction.

• Journal of Korean Ophthalmic Optics Society
• /
• v.19 no.1
• /
• pp.99-104
• /
• 2014

Purpose: This study was to investigate the functional improvement in peripheral vision following eccentric viewing training. Methods: 14 subjects with normal vision took a part with their right eye, peripheral retinal which is $20^{\circ}$ lateral area from the fovea was examined for contrast sensitivity(CS). Eccentric viewing training was performed for 21days with an hour image viewing and examination was repeated. Results: The critical durations for 0.7 cpd were increased 2.67(467 ms) for pre-eccentric viewing training to 2.79(616 ms) for post-eccentric viewing training (p>0.05). The critical durations for 3.0 cpd were also increased 2.53(341 ms) for pre-eccentric viewing training to 3.04(1102 ms) for post-eccentric viewing training (p>0.05). Conclusions: It is recommended to use higher spatial frequency with higher CS for eccentric viewing training and to train more frequently for a short time. Moreover, the study on Korean standardizing of the visual rehabilitation for low vision based on the etiology is sorely required.

• Clinics in Shoulder and Elbow
• /
• v.17 no.1
• /
• pp.25-30
• /
• 2014

Background: Normal elbow joint kinematics has been widely studied in cadaver, whilst in vivo study, especially of the forearm, is rare. Our study analyses, in vivo, the kinematics of normal forearm and of malunited forearm using a three-dimensional computerized simulation system. Methods: We examined 8 patients with malunited Monteggia fracture and 4 controls with normal elbow joint. The ulna and radius were reconstructed from CT data placing the forearm in three different positions; full pronation, neutral, and full supination using computer bone models. We analyzed the axis of rotation 3-dimentionally based on the axes during forearm rotation from full pronation to full supination. Results: Axis of rotation of normal forearm was pitch line, with a mean range of 2 mm, from full pronation to full supination, connecting the radial head center proximally and ulnar fovea distally. In normal forearm, the mean range was 1.32 mm at the proximal radioulnar joint and 1.51 mm at the distal radioulnar joint. However in Monteggia fracture patients, this range changed to 7.65 mm at proximal and 4.99 mm at distal radoulnar joint. Conclusions: During forearm rotation, the axis of rotation was constant in normal elbow joint but unstable in malunited Monteggia fracture patients as seen with radial head instability. Therefore, consideration should be given not only to correcting deformity but also to restoring AOR by 3D kinematics analysis before surgical treatment of such fractures.

• Korean Journal of Cognitive Science
• /
• v.34 no.4
• /
• pp.315-347
• /
• 2023

This study aimed to investigate the semantic preview effect in the parafoveal processing of words that are presented in advance in the parafoveal area ahead of the fixation point, benefiting word processing in the fovea. Using the boundary technique in eye-tracking experiments, 25 Chinese-Korean bilinguals, whose native language is Chinese, were presented with 96 sentences that contained a mix of Chinese and Korean, where Korean words were associated with Chinese characters semantically. The study aimed to determine whether a semantic preview effect could be extracted in reading. The experimental sentences were divided into four conditions: the same Korean native word condition (e.g., "나라" meaning "country"), the same Korean word with semantic equivalent in Chinese condition (e.g., "국가" meaning "country"), the same Chinese condition with semantic equivalent in Korean (e.g., "国家" meaning "country"), and the unrelated Chinese condition to the target word (e.g., "围裙" meaning "apron"). The results showed a preview effect in both the Korean word and Chinese word conditions, with a larger preview effect observed in the Chinese word condition compared to the Korean word condition.

• The Journal of Korean Academy of Prosthodontics
• /
• v.33 no.4
• /
• pp.753-768
• /
• 1995

For accurate impression taking of dental patient and esthetic denture treatment of ednetulous patient, measuring between intraoral anatomic landmarks is useful.In this study the subjects selected at a random were two-jundred forty persons with a mean age 22.5(range 21-24) and were taken impression of by irreversible hydrocolloid impression material(Alginate). On the study model made by dental stone, each individual tray was made and final impresion was taken by border moilding. On final model measurings were performed with 3-dimensional measuring device and the values were analyzed by t-test The results is following : ABOUT THE MEASURED VALUES. 1. The width between maxillary right and left canine cusp tip was average 36.44mm(s.d. 2.48), man 36.67mm, woman 35.83mm(p<0.05). 2. The width between labial height of contour of maxillary right and left canine was average 40.08mm(s.d. 2.42), man 40.29mm, woman 39.52mm(p<0.05). 3. The width between mesio-lingual cusps of maxillary first molar was average 43.14mm(s.d. 3.33), man 43.56mm, woman 42.05mm(p<0.05). 4. The width between buccal alveolar ridge on axis of mesiolingual cusp of right and left maxillary first molar was average 64.89mm(s.d. 3.88), man 65.58mm, woman 62.92mm(p<0.05). 5. The width between buccal alveolar ridge on axis of mesiolingual cusp of right and left maxillary second molar was average 68.58mm(s.d. 3.91), man 69.29mm, woman 66.30mm (p<0.05). 6. The width between right and left hamular notch was average 49.80mm(s.d. 3.96), man 50.70mm, woman 48.20mm(p<0.05). 7. The length from labial heigth of contour of maxillary central incisor to center of incisive papilla was average 9.52mm(s.d. 1.18), man 9.46mm, woman 9.63mm(p>0.05). 8. The length from labial heigth of contour of maxillary central incisor to palatine fovea was average 53.27mm(s.d. 2.93), man 53.93mm, woman 52.08mm(p<0.05). 9. The center of incisive papilla ws located posterior to intercanine line at 0.40mm(s.d. 1.16), man 0.51mm, woman 0.11mm(p<0.05). 10. The height from incisal edge of maxillary central incisor to the labial vestibule was average 21.84mm(s.d. 1.38), man 22.01mm, woman 21.00mm(p<0.05). 11. The height from mesiolingual cusp of maxillary first molar to buccalvestible was average 17.45mm(s.d. 1.42), man 17.56mm, woman 17.08mm(p>0.05). 12. The height from hamular notch to standard occlusal plane was average 6.84mm(s.d. 1.06), man 6.91mm, woman 6.70mm(p>0.05). 13. The height from the deepest point of palatal vault to standard occlsalplane was average 19.95 mm(s.d. 2.03), man 20.19mm, woman 19.12mm(p<0.05). ABOUT THE ARCH FORM 1. The arch form was able to classify into four typr by the rate of the measured values. Each arch form distribution was that the 1 group had 32.46% the 2 group 2.19%, the 3 group 52.83%, the 4 group 12.72%. The sexual composition was that in 1 group man had 73.5%, woman 26.5%, in 2 group man had 40.0%, woman 60.0%, in 3 group man had 83.3%, woman 16.7%, and in 4 group man had 55.17%, woman 44.83%. 2. When canine cusp tip was marked as point O, the intersection point between labial height of contour of maxillary central incisor and intermaxillary suture as point A, height of contour of maxillary second molar buccal alveolar ridge as B point, ${\angle}$AOB was measured $133.8^{\circ}$for the 1 group, $133.0^{\circ}$for the 2 group, $132.3^{\circ}$for the 3 group, $128.9^{\circ}$for the 4 group.