• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.7 no.4
• /
• pp.25-35
• /
• 2008

Variable Message Sign(VMS) is one of the subsystem of Intelligent Transportation Systems (ITS), which is useful for providing real-time information on weather, traffic and highway conditions. However, there are various situations such as incidents/accidents, constructions, special events, etc., which would be occurred on segments, it is unable to control traffic with only the VMS. Thus, it is essential to use of PVMS(Portable Variable Message Signs), which can move to the location needed traffic control and provide more active traffic information than VMS. This study developed a legibility distance model for PVMS messages using in-vehicle Differential Global Positioning Data(DGPS). Traffic conditions, drivers' characteristics, weather conditions and characteristics of PVMS message were investigated for establishing the legibility model based on multiple linear regression analysis. The factors such as height of PVMS characters, spot speed, age, gender and day and night were identified as dominants affecting the variation of legibility distances. It is expected that the proposed model would play a significant role in designing PVMS messages for providing more effective real-time traffic information.

• The Journal of Korean society of community based occupational therapy
• /
• v.6 no.1
• /
• pp.13-23
• /
• 2016

Objective : The aim of the present study was to investigate the effect of aloud reading on handwriting legibility in low-level elementary school children. Methods : The subject of the present study consisted of 45 elementary school 2nd graders who were normally developed checked by the Developmental Test of Visual Perception. Experimental period was conducted total six times that Pre-evaluation once, four times intervention, and Post-evaluation once from November 2 to November 25, 2015. When Pre-evaluation and Post-evaluation was measured the handwriting legibility and speed using Handwriting Skill Test. When intervention divided and implemented to experimental group who handwriting with aloud reading, control group1 who only handwriting, and control group2 who nothing. Pre-evaluation and Post-evaluation identified change the handwriting legibility using Handwriting Skill Test. Result : After intervention, handwriting legibility improve female than male. At word card1, control group1 improve significantly handwriting legibility within group and control group2 come out significant difference but handwriting legibility decrease. At word card2, experimental group and control group1 improve significantly handwriting legibility within group. Experimental group and control group1, control group1 and control group2 come out significant difference between group. Conclusion : The present study demonstrates that handwriting training improve handwriting legibility to elementary school 2nd graders.

• Journal of Korean Ophthalmic Optics Society
• /
• v.20 no.2
• /
• pp.177-186
• /
• 2015

Purpose: The Purpose of this study is to investigate if the relative legibility of optotypes affects the corrected visual acuity in visual acuity test. Methods: After measuring the relative legibility of 'Landolt ring target', 'arabic number target', 'alphabet target' by showing as a single-letter-target in 24 subjects without specific ocular diseases and ocular surgery experience, the relative legibility of 0.8, 1.0, 1.25 row of vision according to type of target in 7 types of chart were compared. After then we compared by measuring the corrected visual acuity according to type of target by using binocular MPMVA test (#7A) in 60 myopic subjects. Results: In 3 types of target the worst relative legibility target was 'Landolt ring target' with legible distance of $98.97{\pm}4.57cm$ and the best relative legibility target was 'alphabet target' with legible distance of $108.42{\pm}3.46cm$. There was no difference of the relative legibility according to type of chart or visual acuity level in the row of vision if other conditions are the same. In 1.0 and 1.25 row of vision the difference of relative legibility according to type of target was shown the statistically significant difference between 'Landolt ring target' and 'alphabet target' as $-0.07{\pm}0.06$ (p=0.02) and $-0.06{\pm}0.06$ (p=0.04) respectively. In myopia the difference of corrected visual acuity according to type of target was statistically significant difference between 'Landolt ring target' and 'arabic number target' as $-0.04{\pm}0.02$ (p=0.02) and it was especially remarkable in the low myopia. Conclusions: Measuring visual acuity with different optotypes could cause the errors in best vision measurement value because there was difference of the relative legibility according to type of target even though visual acuity level is same in the row of vision.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.1295-1298
• /
• 2006

Influences of anti-reflection surface treatment, radius of curvature and ambient illuminance on legibility of reflective-type displays were studied. The results showed that legibility mainly depended on the surface treatment. Better surface treatment also produced less visual fatigue after the letter-search task

• 한국정보디스플레이학회:학술대회논문집
• /
• 2005.07a
• /
• pp.817-820
• /
• 2005

Legibility of electronic paper was evaluated by using the method of letter-search task and subjective visual comfort scaling. The results show that legibility depends on the illumination level, and conventional paper has a higher visual comfort rating than electronic paper although they have the similar performance in the letter-search task.

• Journal of Korean Ophthalmic Optics Society
• /
• v.19 no.2
• /
• pp.279-284
• /
• 2014

Purpose: This study will be a basic research providing data which can reduce eye strain using monitor and electric media by measuring legibility of text color on monitor. Methods: Total experimental subjects who don't have color anomaly and best corrected visual acuity was over 1.0 were 50 and their mean age was $22.83{\pm}1.47$. Reading speed test were carried out with 163 words and subjects who could read over 123 words were selected for legibility examination. Monitor background color was white and letter colors were black, blue, red, and yellow for the legibility examination. Results: In case of text color of black, blue, red, and yellow, Event duration(sec) was measured to 41.89, 42.89, 45.32, and 56.28, respevtively, and reading error (number) was measured to 1.94, 2.74, 3.36, and 5.14. Average of fixation duration(sec) was measured to 0.25, 0.26, 0.27, and 0.32. Conclusions: In this paper, event Duration, reading error and average of fixation duration which can measure the legibility was reduced in a sequence of black blue, red, and yellow.

• Journal of Korean Society of Transportation
• /
• v.25 no.5
• /
• pp.23-32
• /
• 2007

Variable message sign (VMS), which is used for providing real-time information on traffic conditions and incidents, is one of the important components of intelligent transportation systems. VMS messages need to meet the requirements with the consideration of human factors that messages should be readable and understandable while driving. This study developed a legibility distance model for VMS messages using in-vehicle differential global positioning data (DGPS). Traffic conditions, highway geometric conditions, and VMS message characteristics were investigated for establishing the legibility model based on multiple linear regression analysis. The height of VMS characters, speed, and the number of lanes were identified as dominant factors affecting the variation of legibility distances. It is expected that the proposed model would play a significant role in designing VMS messages for providing more effective real-time traffic information.

• Journal of Information Display
• /
• v.4 no.2
• /
• pp.7-12
• /
• 2003

We discuss main techniques to improve legibility of electroluminescent displays. Emphasis is placed on use of destructive optical interference to cancel ambient light reflected from the back electrode of the device. Basic optical principles and material composition of the optical interference contrast-enhancing stack (CES) are presented. We also describe the improved human factors of electroluminescent devices assisted with a CES. Achromatic contrast is the most important contributor to display's legibility. In some conditions color contrast may also be important. Contributing to both luminance and color contrast enhancement, the contrast-enhancing stack may play an important role in various display applications.

• Journal of Korean Society of Transportation
• /
• v.24 no.6 s.92
• /
• pp.21-32
• /
• 2006

The purpose of this study is to determine the economical standard for road signs by verifying the difference in driver's legibility time with respect to the spacing of letters on the toad signs. Laboratory simulations were conducted to confirm the difference in legibility time for six target signs of different spacing. Also. a binary logit model was used to find the main factors, which could lower the rate if misreading. This model involves not only a simple enlargement of signs but also a suitable match of letters and signs along with the optimal spacing of the text letters on the road signs to increase the legibility of the sign. The result of this study verified the importance of spacing in road signs and Proved itself to be an effective method to determine the future standard for the road signs.

• Journal of Korean Society of Transportation
• /
• v.29 no.1
• /
• pp.47-55
• /
• 2011

The purpose of this study was to determine the legibility distance for traffic road sign and traffic sign, fixation duration and number of fixation during the time of recognition of traffic road signs under different vision conditions. This experiment was conducted on a closed-road circuit which has realistic driving road and environment Each participant drove the real vehicle for the experiment and specially built traffic road sign for the experiment and traffic road signs on the side of closed-road circuit were used. Different vision conditions were simulated using spectacle lenses to reach visual acuity 1.0 and 0.8 and it was 1.2 without spectacles and each participant tested under 3 vision conditions.. The result of this study demonstrated that there was a significant difference on legibility distance between visual acuity of 1.2 and 0.8 and there were also significant difference on fixation duration and number of fixations with smaller traffic signs. This study demonstrated the importance of vision correction for driving at night-time, also showed there would be difference on legibility distance and efficiency of eye movement such as fixation duration and number of fixation despite of satisfied visual acuity for driver's license requirement.