• Title/Summary/Keyword: Eyewear

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A Sunglasses Design to Prevent Snow Blindness at High Altitude (설맹 방지를 위한 고소등반용 선글라스 디자인)

  • Choi, Byung-Jin;Jang, Joon-Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.12 no.4
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    • pp.19-22
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    • 2007
  • Recently, the population of people exploring High Mountain trekking or expedition is increasing as an increase in the backpackers. Many accidents occurring at High Mountain above 6,000 m are the results of snow blindness. The damage of cornea and/or retina is direct cause of snow blindness. The UV intensity increases on the hand, along with the altitude caused by decrease in the atmospheric pressure, on the other hand the reflections by bright snow at high mountain area. And it increases approximately 3 times and 4 times higher than the ground level at altitude of 4,000 m and 8,000 m, respectively. The use of sunglasses is more favorable than goggles for the protection of snow blindness at High Mountains. The eye frames that have high mechanical strength and the plastic lenses which can protect UV 100% are recommended. The attachable shielding pads are needed to prevent the incident UV light reflected or scattered from the gap between glasses frame and face. The sunglasses must have flexible and long temples to wind the ears adequately for the prevention of detachment during climbing and it is recommended that the metal frame to be coated with plastics to prevent the eye surroundings from frostbite.

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Analysis of Mechanical Property Changes of Polymer Eyeglass Frames by Thermal Impact (고분자 안경테의 온도에 의한 기계적 물성 변화 분석)

  • Seo, Hogeun;Yoon, Taeyang;Noh, Hyeran
    • Journal of Korean Ophthalmic Optics Society
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    • v.19 no.4
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    • pp.429-434
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    • 2014
  • Purpose: To analyze thermal effect on mechanical properties of domestic commercial polymer-based eyewear frames. Methods: In this study, materials of cellulose acetate, polyamide, epoxy, and polyetherimide were exposed to high or low temperature and were mounted on universal test machine (TO-100-IC) for tensile strength test. Elastic behavior, Young's modulus, maximum displacement, and fatigue were tested with various temperature ($-25^{\circ}C$, $25^{\circ}C$, $60^{\circ}C$). Results: As a result, at room temperature, displacements of materials were changed with increasing impact load. At low temperature ($-25^{\circ}C$), maximum displacements of all specimens were decreased but young's modulus were increased. However, at high temperature, maximum displacements of all specimens were increased but young's modulus were decreased. Conclusions: Degree of displacements due to fatigue behavior was increased following direction of PEI, epoxy, polyamide, acetate. We concluded that commercial polymers used in eyewear frames physical properties were changed differently to exposed temperature.

Individual Fit Testing of Hearing Protection Devices Based on Microphone in Real Ear

  • Biabani, Azam;Aliabadi, Mohsen;Golmohammadi, Rostam;Farhadian, Maryam
    • Safety and Health at Work
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    • v.8 no.4
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    • pp.364-370
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    • 2017
  • Background: Labeled noise reduction (NR) data presented by manufacturers are considered one of the main challenging issues for occupational experts in employing hearing protection devices (HPDs). This study aimed to determine the actual NR data of typical HPDs using the objective fit testing method with a microphone in real ear (MIRE) method. Methods: Five available commercially earmuff protectors were investigated in 30 workers exposed to reference noise source according to the standard method, ISO 11904-1. Personal attenuation rating (PAR) of the earmuffs was measured based on the MIRE method using a noise dosimeter (SVANTEK, model SV102). Results: The results showed that means of PAR of the earmuffs are from 49% to 86% of the nominal NR rating. The PAR values of earmuffs when a typical eyewear was worn differed statistically (p < 0.05). It is revealed that a typical safety eyewear can reduce the mean of the PAR value by approximately 2.5 dB. The results also showed that measurements based on the MIRE method resulted in low variability. The variability in NR values between individuals, within individuals, and within earmuffs was not the statistically significant (p > 0.05). Conclusion: This study could provide local individual fit data. Ergonomic aspects of the earmuffs and different levels of users experience and awareness can be considered the main factors affecting individual fitting compared with the laboratory condition for acquiring the labeled NR data. Based on the obtained fit testing results, the field application of MIRE can be employed for complementary studies in real workstations while workers perform their regular work duties.

Machinability Evaluation and Cutting Condition Selection of Cellulose Acetate for Manufacturing of High-quality Spectacle Frames (고품위 안경테 제작을 위한 안경테 소재(Cellulose Acetate)의 가공성 평가 및 절삭조건 선정)

  • Kang, Ik-Soo;Lee, Seung-Yong;Choi, Hyun-Jin;Lee, Tae-Ho;Choi, Sung-Dae
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.11 no.4
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    • pp.20-24
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    • 2012
  • The objective of this study is to investigate proper cutting conditions of cellulose acetate(CA) for eyewear frames. Various cutting experiments with variation of spindle speeds and feed rates are conducted to evaluate the machinability of CA. The machinability of CA materials were discussed in terms of the cutting forces, surface roughnesses and chip formations. The cutting conditions of high spindle speeds and the feed per tooth of less than 0.05mm are recommended considering the surface roughnesses and chip formations. Also, the correlation between the surface roughness and the chip formation is investigated. These results are able to be applied to design the high-speed machine tool of CA frame.

Naive Bayes classifiers boosted by sufficient dimension reduction: applications to top-k classification

  • Yang, Su Hyeong;Shin, Seung Jun;Sung, Wooseok;Lee, Choon Won
    • Communications for Statistical Applications and Methods
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    • v.29 no.5
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    • pp.603-614
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    • 2022
  • The naive Bayes classifier is one of the most straightforward classification tools and directly estimates the class probability. However, because it relies on the independent assumption of the predictor, which is rarely satisfied in real-world problems, its application is limited in practice. In this article, we propose employing sufficient dimension reduction (SDR) to substantially improve the performance of the naive Bayes classifier, which is often deteriorated when the number of predictors is not restrictively small. This is not surprising as SDR reduces the predictor dimension without sacrificing classification information, and predictors in the reduced space are constructed to be uncorrelated. Therefore, SDR leads the naive Bayes to no longer be naive. We applied the proposed naive Bayes classifier after SDR to build a recommendation system for the eyewear-frames based on customers' face shape, demonstrating its utility in the top-k classification problem.

A Study on the Change of Opticion's perception and Actual conditions on Eyewear Dispensing (안경조정에 대한 안경사의 인식 및 실태 변화에 관한 연구)

  • Park, Jeong-Sik;Lee, Jeong-Yeong;Jang, Woo-Yeong
    • Journal of the Korea society of information convergence
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    • v.7 no.1
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    • pp.47-53
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    • 2014
  • This study was carried out recognition and status changes of optician for glasses fitting. It based on a survey results of twice in relation to the glasses fitting. The results are as follows. The ratio of glasses fitting about optician operation appeared to increase gradually. The positive awareness change appeared from the customer and optician about the cost charging about the glasses fitting. In the case of a plastic glasses, the burden for the inconvenience feeling and fitting frequency showed an increase with relation to the temple fitting. To reduce the burden of glasses fitting, The continuous education for the correct glasses usage need.

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Classification and Characteristics of Augmented Reality Contents of Fashion Brands (패션 브랜드의 증강현실(AR) 콘텐츠 유형 및 특성)

  • Lee, Hyun-Jin;Ku, Yang-Suk
    • Fashion & Textile Research Journal
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    • v.22 no.3
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    • pp.310-322
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    • 2020
  • This study investigated the classification and characteristics of augmented reality (AR) content of fashion brands. The AR contents of fashion brands were classified according to user participation space and content delivery method. Based on these types, eight case studies were conducted, along with a discussion of AR characteristics in terms of presence, interactivity, and immersion. The results showed that AR content could be divided into four types: offline visit-external information type, offline visit-internal experience type, online utilization-external information type, and online utilization-internal experience type. It was also found that there were differences in characteristics for each type of AR content. First, the offline visit-external information type requires various new content that can provide entertainment immersion to users. Second, the offline visit-internal experience type requires a powerful inducement for users to visit a specific space providing AR content and to participate in augmented environments. Third, the online utilization-external information type needs a series of AR content that can consistently incite users' curiosity about brands and products. Fourth, the online utilization-internal experience type needs effective content to improve users' shopping experience with the virtual fitting of fashion accessories, such as eyewear, hats, jewelry, and watches. Accordingly, fashion companies should create contents that can provide appropriate presence, interactivity, and immersion by AR type.

Analysis on Causes of Stagnation in Domestic Eyeglasses Industry (국내 안경산업의 침체원인 분석)

  • Lee, Jeong-Yeong;Park, Eun-Kyu;Kim, Dae-Nyun
    • Journal of Korean Ophthalmic Optics Society
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    • v.11 no.1
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    • pp.43-47
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    • 2006
  • Korean eyeglasses export has continuously decreased at the annual average rate of 10% since year 2000. On the other hand, China - the number 1 competing country - is chasing after Korea while accomplishing average 20% of export increase per annum after year 2000. Considering these factors, main cause of stagnation in domestic eyeglasses industry can be seen as China's pursuit propelled by their low labor costs as well as investment on Research &Development. Other important causes are insufficient investment on R &D, decrease in competitiveness due to increase of import, deficiency of exploitative ability on own brand and own design, lack of infrastructure in eyeglasses expo, and etc.

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Robust Similarity Retrieval for Radial Distortion of Object Shape Based on the Normalized Phase Angles and Moment

  • An, Young Eun;Kim, Tae Yeun
    • Journal of Integrative Natural Science
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    • v.12 no.2
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    • pp.35-43
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    • 2019
  • In the content-based image search properties, form information is simple because only the contours of objects are available, and although it can effectively extract the characteristics of the objects, it is sensitive to external noise. The radial distortion, one of these noises, is most prominent in the eyewear and, due to the structural characteristics of the imaging equipment, radiative distortion occurs in almost all imaging equipment. It is very important to determine the similarity of the objects in the images in which these distortions occurred to the actual objects. In order to improve this problem, we propose a strong image search technique for formative noise and radiative distortion using regularization phase angles and moments. Through simulation using Wang DB, the proposed algorithm proved excellent performance for radiation distortion that occurs in general. In addition, a system optimized for database can be implemented by making appropriate changes to the threshold values, enabling image retrieval with the desired level of confidence in various systems. The algorithm proposed in this paper is expected to be utilized as an optimal imaging system by extracting morphological form information of multimedia data.

The Relationship between Refractive Myopia and Corneal Astigmatism in Korea Women University Students (한국 여자대학생의 굴절성 근시와 각막난시 관계)

  • Kim, Douk-Hoon
    • Journal of Korean Clinical Health Science
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    • v.1 no.1
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    • pp.1-7
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    • 2013
  • Purpose. To analysis the prevalence of the myopia and corneal astigmatism in Korea women university students. Methods. From August 2011 to December 2012, one hundreds subjects were performed in refraction test using the Auto-Keratometry. Results. The mean age of the 100 subjects (200 eyes) was $21.23{\pm}2.34$. The mean spherical refractive power was -$1.78{\pm}1.65$(OD) and -$1.83{\pm}1.67$(OS) Diopter. The mean astigmatism power was $1.22{\pm}0.96$ (OD) and $1.27{\pm}0.91$ (OS). The mean corneal astigmatism was $1.44{\pm}0.81$(OD) and $1.55{\pm}0.93$(OS). Corneal astigmatism was between 0.25 D and 1.25 D in 67.7% of eyes, 1.25 D or higher in 27.5% eyes, and less than 0.25 D in 4.8% of eyes. Astigmatism was with the rule in 65%, against the rule in 31.5%, and oblique in 3.5%. There was a statistical significance between right eye and left eye in the spherical equivalent power(p=0.002). Also there was a statistical significance between spherical power and refractive astigmatism in OD(p=0.006) and OS(0.003) and a statistical significance between corneal astigmatism and refractive astigmatism in OS(p=0.0003). However, there was not a statistical significance between spherical power and corneal astigmatism in OD(p=0.08) and OS(0.1) and a statistical significance between corneal astigmatism and refractive astigmatism in OS(p=0.48). Conclusions. In this study, these results suggested that the analysis of the refractive myopia and corneal astigmatism can provide the visual correct and useful diagnosis information for the eyewear dispensing, contact lens fitting and corneal refraction surgery.

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