목적 : 본 연구는 Orthokeratology(OK) 렌즈와 기존의 단안렌즈(SV) 안경을 착용한 근시 청소년의 굴절이상을 분석하여 OK 렌즈가 근시 진행에 미치는 영향을 살펴보고자 하였다. 방법 : 연구방법은 중국 길림성 북화대학부속병원 안과를 방문한 청소년 환자 100명을 대상으로 50명의 환자를 OK렌즈군과 단초점 안경군으로 나누었다. 두 그룹의 환자 모두 1년 동안 추적관찰하여 시력(VA), 구면등가굴절 (SE), 안축 길이(AL), 각막 내피 세포 수(CEC), 중심 각막 두께(CCT) 및 압력(IOP)의 변화를 비교하였다. 통계분 석은 SPSS 소프트웨어를 이용하여 독립표본 T-test로 데이터를 분석하였으며, p<0.050을 통계적으로 유의한 것 으로 간주하였다. 결과 : Euclid Orthokeratology(OK)렌즈를 착용한 환자의 시력이 서서히 향상되었으나, 단초점 안경을 착용한 환자들은 시력이 감소하는 추세를 보였으며, 두 그룹 간의 차이는 통계적으로 유의하였다(p<0.010). 굴절검사 결과 는 OK 렌즈를 착용한 후 굴절이상이 유의하게 감소하였으며, 안경을 착용한 환자들은 굴절이상이 증가한 것으로 나타났다. 두 그룹 간의 차이는 통계적으로 유의하게 증가하였다(p<0.010). 또한, 안축 길이의 분석 결과, OK 렌 즈를 착용한 환자들의 안축 길이는 기준값 대비 0.18±0.18 mm 증가하였고, 안경을 착용한 환자들의 안축 길이는 기준값 대비 0.61±0.20 mm 증가하였다. 두 그룹 간의 차이는 통계적으로 유의하게 증가하였다(p<0.001). OK 렌즈를 착용한 환자들은 안압, 각막 내피 세포 수 및 중심 각막 두께에서 기준값 대비 유의한 변화가 없었다 (p>0.050). 결론 : 안경 대비 각막교정렌즈가 구면 등가 구면굴절력(SE)를 감소시키고 시력을 향상시켰으며, 안축 연장을 늦추는데 더 효과적임을 알 수 있었다.

Deep learning-based computer vision anomaly detection algorithms are widely utilized in various fields. Especially in the manufacturing industry, the difficulty in collecting abnormal data compared to normal data, and the challenge of defining all potential abnormalities in advance, have led to an increasing demand for unsupervised learning methods that rely on normal data. In this study, we conducted a comparative analysis of deep learning-based unsupervised learning algorithms that define and detect abnormalities that can occur when transparent contact lenses are immersed in liquid solution. We validated and applied the unsupervised learning algorithms used in this study to the existing anomaly detection benchmark dataset, MvTecAD. The existing anomaly detection benchmark dataset primarily consists of solid objects, whereas in our study, we compared unsupervised learning-based algorithms in experiments judging the shape and presence of lenses submerged in liquid. Among the algorithms analyzed, EfficientAD showed an AUROC and F1-score of 0.97 in image-level tests. However, the F1-score decreased to 0.18 in pixel-level tests, making it challenging to determine the locations where abnormalities occurred. Despite this, EfficientAD demonstrated excellent performance in image-level tests classifying normal and abnormal instances, suggesting that with the collection and training of large-scale data in real industrial settings, it is expected to exhibit even better performance.

Before the unification of China during the Qin Dynasty, there had already been exchanges and contacts between China and Japan through the ancient Maritime Silk Road, leading to increasingly close and frequent connections between the two nations. Maritime exchanges between China and Japan began as early as the Qin Dynasty, with the establishment of the Silk Road during the Han Dynasty. During this period, Sino-Japanese interactions were characterized by their occasional nature. In the Sui and Tang Dynasties, these interactions entered a developmental stage marked by noticeable diversity. By the Song and Yuan Dynasties, Sino-Japanese relations gradually reached their zenith, with a heightened political significance. However, these interactions began to decline during the Ming and Qing Dynasties, with a stronger emphasis on bilateral exchanges. The historical and contemporary relevance of Sino-Japanese interactions within the framework of the ancient Maritime Silk Road has played a crucial role in promoting trade, cultural integration, and national development between China and Japan, providing a solid historical foundation for contemporary efforts to enhance exchanges and cooperation in the Northeast Asia region.

Abstract Purpose : In this study, α-Lipoic acid and pyridine were added to hydrogel materials and silicone hydrogel materials, respectively, to manufacture contact lens to evaluate changes in physical properties. Methods : N,N-Dimethylacrylamide (DMA), 2,2'-Azobis (2-methylpropionitrile) (AIBN), an initiator, and Ethylene glycol dimethacrylate (EGDMA), crosslinking agent, were used basic mixing ratio, and hydrogel materials were prepared by thermopolymerization at 100°C for 1 hour based on 2-Hydroxyethyl methacrylate (HEMA). Silicone hydrogel materials were prepared by thermopolymerization at 130°C for 2 hours based on Silicone monomer (SID). The properties of contact lenses were evaluated by adding 0.05% of 3-hydroxypyridine N-oxide and (R)-(+)-α-Lipoic acid by ratio to each material. Results : A lens manufactured by adding alpha lipoic acid to silicone hydrogel materials showed a tendency to increase wettability and decrease refractive index. A lens manufactured by adding pyridine to silicone hydrogel materials showed UV-A blocking ability, and the refractive index tended to increase. In addition, a contact lens manufactured by adding alpha lipoic acid and pyridine together showed antimicrobial properties, reduced surface roughness, and increased wettability and oxygen permeability according to the ratio of alpha lipoic acid addition. Conclusion : It is judged that alpha lipoic acid and pyridine are expected to improve wettability and oxygen permeability of the lens and to be used as contact lens materials with antibacterial properties. Key words : Alpha lipoic acid, Antimicrobial, Oxygen permeability, Pyridine, Wettability

Abstract Purpose : This study analyzed physical properties using 1,6-Hexanediol diacrylate (HDDA) as an additive to improve functionality of hydrogel lens such as durability. It was checked whether HDDA can be applied as a crosslinking agent in place of ethylene glycol dimethacrylate (EGDMA). Methods : Polymerization used thermal polymerization and photopolymerization methods, and HDDA was added to each polymerization method at a ratio of 1∼20%. Optical and physical characteristics of the manufactured lens were evaluated by measuring spectral transmittance, refractive index, water content, tensile strength, contact angle, and AFM. Results : Regardless of the polymerization method, the tensile strength ranged from 0.232~0.408 kgf/mm2 in thermal polymerization and from 0.146~0.429 kgf/mm2 depending on the addition ratio of HDDA. In addition, as a result of using HDDA instead of EGDMA, it was confirmed that the physical characteristics of the lens were similar to that of EGDMA, and in the case of tensile strength, HDDA was much improved. Conclusion : HDDA has been shown to be effective in improving the functionality of hydrogel lens and to improve stability and durability. In addition, it is believed that it can be used in various ways as an ophthalmic material as well as a photopolymerization crosslinking agent. Key words : Crosslinking agent, Tensile strength, 1,6-Hexanediol diacrylate, Hydrogel lens

Abstract Purpose : To determine the perceptions of soft contact lens wearers regarding contact lens wear and care, and their knowledge of adverse effects of contact lens wear by self-assessment. Methods : An online survey using smartphone was conducted by Naver and Google questionnaires among university students who have experience wearing soft contact lenses. Results : Two hundred twenty-eight soft lens wearers were participated in the study. The average age was 20.9±1.7 years (female 72.8%; male 27.2%) were university students. Approximately 25.4% of respondents did not receive training and practices for safe soft lens wear and 14.1% evaluated themselves as poor at wearing and caring for soft lenses. The most uncomfortable symptom of soft lens wear was dryness at 76.3%, and 36.0% experienced soft lens-related adverse events. The higher type of adverse event was conjunctivitis, and the most common self-reported cause of contact lens-related adverse events was improper lens care and non-compliance to lens wear regimens. Conclusion : Based on the self-assessment of soft lens care that resulted from this survey, we believe that a more proactive approach to intervention by contact lens practitioners is still needed to prevent the risk of adverse events and improve soft lens wearer behavior. Key words : Compliance, Contact lens-related adverse events, Self-assessment, Soft contact lens Authors ORCID:†

Infrared radiation (IR) refers to the region of the electromagnetic radiation spectrum where wavelengths range from about 700 nm to 1 mm. Any object with a temperature above absolute zero (0 K) radiates in the infrared region, and a material that transmits radiant energy in the range of 0.74 to 1.4 um is referred to as a near-infrared optical material. Germanatebased glass is attracting attention as a glass material for infrared optical lenses because of its simple manufacturing process. With the recent development of the glass molding press (GMP) process, thermal imaging cameras using oxide-based infrared lenses can be easily mass-produced, expanding their uses. To improve the mechanical and optical properties of commercial materials consisting of ternary systems, germanate-based heavy metal oxide glasses were prepared using a melt-cooling method. The fabricated samples were evaluated for thermal, structural, and optical properties using DSC, XRD, and XRF, respectively. To derive a composition with high glass stability for lens applications, ZnO and Sb2O3 were substituted at 0, 1, 2, 3, and 4 mol%. The glass with 1 mol% added Sb2O3 was confirmed to have the optimal conditions, with an optical transmittance of 80 % or more, a glass transition temperature of 660 °C, a refractive index of 1.810, and a Vickers hardness of 558. The possibility of its application as an alternative infrared lens material to existing commercial materials capable of GMP processing was confirmed.

목적 : 본 연구는 RGP 렌즈 착용 상태에서 렌즈후면과 각막전면에 존재하는 눈물층의 두께와 눈물의 굴절력을 측정하였다. 방법 : 본 연구의 대상자는 20명(평균연령 23.02±1.89세)이 참여하였다. 각 참여자는 각막곡률의 측정값에 따 라 피팅상태가 flat fit, alignment fit, steep fit이 되도록 3개의 다른 BC의 RGP를 피팅하였다. RGP렌즈를 착 용한 상태에서 OCT로 눈물층 두께 측정, 자동굴절계를 이용하여 눈물렌즈의 굴절력을 측정하였다. 결과 : 측정결과 베이스 커브에 따라 발생한 렌즈 후면과 각막 간의 눈물층 높이의 평균값은 플랫한 피팅 상태 에서는 6.20±1.06 μm, 정렬된 피팅상태에서는 9.10±1.55 μm, 스팁한 피팅상태에서는 12.5±1.50 μm으로 통 계적으로 유의한 차이가 나타났다(F(2, 57)=103.05, p<0.010). 피팅상태에 따라 생성된 눈물렌즈의 굴절력은 플 랫 피팅인 경우 –0.85±0.75 D, 정렬된 경우 –0.48±0.85 D, 스팁 피팅인 경우 +1.56±0.77 D로 통계적 으로 유의하게 나타났다(F(2, 57)=53.71,p<0.010). 3가지 피팅에 따라서 RPG 렌즈 후면과 각막전면의 있는 눈 물 렌즈의 두께와 눈물 렌즈로 생성된 굴절력과의 상관관계 분석에서 r=0.58로 다소 높은 상관관계를 보였다. 결론 : 본 연구에서는 정렬된 피팅이 된 경우, 최소의 굴절력 조정이 요구되며, 반면 스팁한 피팅인 경우 더 많 은 조정이 필요하다.

The advent of virtual reality and augmented reality technologies have pushed user’s expectation for online experience to a new level. Social connections via texts alone can no longer satisfy appetite for the reality of virtual interaction. Subsequently, the metaverse is invented to reimagine the way people work, play, socialize and live online (Xi et al., 2022). Metaverse is “the post-reality universe, a perpetual and persistent multiuser environment merging physical reality with digital virtuality” (Mystakidis, 2022). The speed at which the Metaverse has evolved both in definition (first coined in 1992 by science fiction author Neal Stephenson) and research but also in practice, has been phenomenal. Earlier visions of what the Metaverse would be were limited to gaming (for example, Roblox, Fortnite, Zepeto), and gaming is still considered to be the most popular service in the Metaverse (Shin, 2022), where reality is replicated through the creation of a virtual 3D space including avatars interacting and communicating. This current immersive extended reality is a space where people not only can play, but work, learn, socialize, buy, and much more (Hollensen, Kotler, & Opresnik, 2022). It could be fair to assume that the potential of Metaverse being much more than simply gaming, took off after Mark Zuckerberg’s continuous references to the metaverse throughout 2020 and 2021, and the subsequent change of Facebook’s name to Meta in 2021. By 2026, it is estimated that 25% of people worldwide will spend at least one hour a day in the metaverse for digital activities, including shopping, working, entertainment and social interaction (Johnson, 2022).

The present study compared the effectiveness of virtual influencers (VIs) to human influencers through the theoretical lens of the uncanny valley and parasocial relationship using an online experiment. Specifically, we posited that highly humanlike VIs may evoke the feeling of the uncanny valley, as compared to human influencers or cartoonlike influencers, which, in turn, would act as a psychological barrier to building a parasocial relationship with the specific type of virtual influencer and decrease advertising attitude. The results indicated that people do feel the uncanniness from both highly humanlike and cartoonish influencers as compared to human influencers. This particular psychological experience negatively influenced the parasocial relationship, which, in turn, negatively affected the attitude toward a social media advertisement featuring the VIs. However, importantly, this effect was moderated by individual differences in anthropomorphism. This is one of the first studies that directly compared the effectiveness of different types of social media influencers in a rigorously designed experimental setting and expands the previous research on Vis, uncanny valley, and parasocial relationship. Both theoretical and managerial contributions of the study were discussed.

목적 : 최근 전자기기의 발달로 인해 근거리 작업이 증가하고 있으며, 이로 인해 안 건강에 대한 우려가 증가함 에 따라 청광 차단에 대한 관심이 증가하고 있다. 방법 : 유해 광선 차단이 가능한 기능성 콘택트렌즈 소재 개발을 위해 reactive yellow 86을 안료 중합체에, 그리고 propyl gallate를 실리콘 하이드로겔 소재에 첨가제로 각각 사용하여 안 의료용 소프트 콘택트렌즈 제조에 적용하였다. 결과 : propyl gallate의 첨가량에 따라 접촉각이 68.25~42.50˚로 측정되었으며, 습윤성이 향상되는 것으로 나타났다. 또한, 제조된 컬러 소프트 콘택트렌즈는 산소투과성 및 습윤성이 우수함과 동시에 자외선 및 청광 차단 효과를 나타내었다. 결론 : reactive yellow 86 및 propyl gallate가 적용된 컬러 콘택트렌즈의 재료의 경우, 기본적인 안 의료용 하이드로젤 렌즈의 물성을 만족시킴과 동시에 우수한 자외선 및 청광차단 효과를 가지는 것으로 판단된다.

Idamsokchan (耳談續纂, Additions to an Earful of Conversation) is an early collection of Korean proverbs capturing 418 proverbs from China and Korea with Chinese translation, most of which are social proverbs. Through a contrastive analysis of the formation mechanism of social proverbs in Idamsokchan, this study explores the influence of Chinese and Korean mindsets on language. Specifically, the study analyzes the structure, semantics, and topic of social proverbs from both Chinese and Korean sources in Idamsokchan. The results indicate that the influence of concrete-versus-abstract and practical-versus-theoretical thinking on proverbs varies. Generally, Korean proverbs exhibit a tendency towards abstract thinking, whereas Chinese proverbs are characterized by an emphasis on concrete thinking. The structural characteristics of Korean and Chinese proverbs are distinct. Korean proverbs are typically formed as a single sentence, whereas Chinese proverbs often employ fixed sentence patterns and connectives. In addition, the syntax of Chinese translations of Korean proverbs in Idamsokchan tends to be morphological. Regarding semantics, a greater proportion of Korean proverbs are of a philosophical nature when compared to Chinese proverbs. While Korean proverbs employ a simplex network and extend metaphors through contrast, Chinese proverbs are adept at using the creative double-scope network. In terms of topic selection, both Korean and Chinese proverbs, cover eight types of topics, using interrogative pronouns as subjects. Nonetheless, the contrastive-topic structure is more commonly observed in Chinese proverbs. Moreover, while the first-person singular pronoun is commonly utilized as a topic in Korean proverbs, the equivalent in Chinese proverbs is the third-person pronoun 其 (qi).

Numerical analysis has been carried out to predict the thermal characteristics for a LED lens in mold core system. These thermal characteristics inside the lens are largely affected by geometry, material, and initial conditions of the mold core and lens system. Local temperature and heat flux variation inside the lens are compared for several initial temperatures. Maximum temperature inside the lens was decreased rapidly from the beginning of cooling process up to about 10 seconds. There was also large variation of the heat flux at the upper and lower surfaces of the lens with initial temperature distribution. And the heat flux from the thin lower surface of the lens was relatively higher than the opposite-side thick region. In addition, overall heat transfer rate from the lens through the mold core has similar transient distribution from the beginning. These results can be applied as basic heat transfer data for the LED lens design and manufacturing process in the mold core system.

For a plastic diffusion lens to uniformly diffuse light, it is important to minimize deformation that may occur during injection molding and to minimize deformation. It is essential to control the injection molding condition precisely. In addition, as the number of meshes increases, there is a limitation in that the time required for analysis increases. Therefore, We applied machine learning algorithms for faster and more precise control of molding conditions. This study attempts to predict the deformation of a plastic diffusion lens using the Decision Tree regression algorithm. As the variables of injection molding, melt temperature, packing pressure, packing time, and ram speed were set as variables, and the dependent variable was set as the deformation value. A total of 256 injection molding analyses were conducted. We evaluated the prediction model's performance after learning the Decision Tree regression model based on the result data of 256 injection molding analyses. In addition, We confirmed the prediction model's reliability by comparing the injection molding analysis results.

목적: 초기노안을 대상으로 중심-근용 멀티포컬 콘택트렌즈 착용 시 구면수차가 시력에 미치는 영향을 확인하고자 하였다. 방법 : 초기노안 50명을 대상으로 중심-근용 멀티포컬 콘택트렌즈 착용하고 일주일의 적응 기간 후 원·근거 리 시력과 구면수차의 변화 및 원·근거리 시력 개선에 필요한 추가 교정도수를 확인하였고, 시력만족도는 설문조 사로 확인하였다. 결과 : 대상자의 평균 교정굴절력은 –2.65±1.67 D, 가입도는 +1.15±0.05 D이었으며, 안구 구면수차는 0.010±0.028 ㎛였으며, 이 중 37명(72 %)은 양의 구면수차(0.028±0.017 ㎛)를, 13명(28 %)은 음의 구면수차 (–0.020±0.010 ㎛)를 갖고 있었다. 중심-근용 멀티포컬 콘택트렌즈를 착용한 후 양의 구면수차를 가 진 그룹은 -0.012±0.005 ㎛로, 음의 구면수차를 가진 그룹은 –0.043±0.010 μm로 모두 음(-)의 방향으로 증 가하였다(p<0.050). 멀티포컬 콘택트렌즈를 착용한 후 100% 원거리 시력(logMAR)은 양의 구면수차를 가진 그룹 에서는 –0.014±0.090, 음의 구면수차를 가진 그룹에서는 0.022±0.120으로 양의 구면수차를 가진 그룹에서 더 좋았고(p<0.001), 100% 고대비 근시력(logMAR)은 양의 구면수차를 가진 그룹에서는 0.127±0.090, 음의 구면 수차를 가진 그룹에서는 0.118±0.090으로 음의 구면수차를 가진 그룹에서 더 좋았다(p<0.001). 설문조사 결과 에서는 양의 구면수차를 가진 그룹에서는 원거리에서 높은 만족도를 보였고, 음의 구면수차를 가진 그룹에서는 중 간거리와 근거리 영역에서 만족도가 높았다(p<0.050). 결론 : 중심-근용 멀티포컬 콘택트렌즈를 처방 후 구면수차가 변할 수 있고, 착용자의 안구 구면수차에 따라 원·근거리 시력 만족도가 달라질 수 있음을 확인하였다. 따라서 멀티포컬 콘택트렌즈를 처방할 때 착용자의 구면 수차를 확인한다면 처방 성공률을 더 높일 수 있을 것으로 사료된다.

목적: 코로나19 상황에서 일부 안경사를 대상으로 콘택트렌즈 관리 지식 및 관리 교육의 실천 수준을 알아보고, 코로나19 감염예방을 위한 기초 자료를 제공하고자 하였다. 방법 : 2021년 3월부터 6월까지 국내 안경원에서 1년 이상의 근무 경력을 가지고 있는 122명의 안경사를 대 상으로 온라인 설문지를 이용하여 진행하였다. 대상자의 성별은 남자가 75명, 여자가 47명이었으며 평균 연령은 29.80±6.92세였다. 연구 도구는 대상자의 일반적 특성과 코로나19에 대한 지식(0~2점) 및 코로나19 상황에서 콘택트렌즈의 관리에 관한 지식(0~2점), 그리고 감염예방을 위한 관리 교육의 실천(0~3점)에 대한 항목으로 총 27문항의 설문지를 이용하였다. 결과 : 대상자들의 코로나19 지식의 평균 점수는 1.61±0.30점, 콘택트렌즈 관리에 대한 지식의 평균 점수는 1.69±0.29점, 관리 교육의 실천은 2.45±0.45점이었다. 코로나19의 지식에서 ‘코로나19의 증상’(1.93±0.34점) 문항이 가장 높은 지식수준을 보였고, ‘코로나19의 병원체는 SARS-CoV-2’(1.18±0.70점)에서는 가장 낮은 점 수를 보였다. 콘택트렌즈 관리에 관한 지식 문항에서는 ‘코로나19 상황에서 콘택트렌즈 세척과 헹굼은 필수적인 관리지침’(1.98±0.13점)에서 가장 높은 점수를 보였다. 실천 문항에서는 일반적인 콘택트렌즈의 관리 수칙은 잘 지키고 있었지만 ‘독감, 발열, 기침 등의 증상이 있으면 렌즈 착용을 중단하도록 교육한다’(1.71±1.10점)에서는 낮은 수준을 보였다. 결론 : 코로나19 상황에서 일부 안경사들의 일반적인 콘택트렌즈 관리 수칙은 높은 지식 및 실천 점수를 보였 으나, 일부 항목은 낮은 점수를 보여 감염예방을 위한 전문적인 항목의 개발과 교육이 필요하다고 생각된다.

In this paper, to improve the optical quality of aspherical plastic lenses for mobile use, the optimal molding conditions that can minimize the phase difference are derived using injection molding simulation, design of experiments, and machine learning. First, factors affecting the phase difference were derived using the design of the experiment method, and a data set was created using the derived factors, followed by the machine learning process. After predicting the model trained using the generated training data as test data and verifying it with the performance evaluation index, the model with the best predictive performance was the random forest model. Therefore, to derive the optimal molding conditions, random forests were used to predict 10,000 random pieces of data. As a result of applying the derived optimal molding conditions to the injection molding simulation, the phase difference of the lens could be reduced by 8.2%.

목적: 상분리가 일어나지 않는 실리콘하이드로겔 콘택트렌즈(silicone hydrogel contact lens, SH-CL) 제조에 적합한 실리콘 모노머의 구조를 알아보고자 한다. 방법 : HEMA(2-hydroxyethyl methacrylate)와 세 종류의 실리콘 모노머, TRIM[3-(trimethoxysilyl)propyl methacrylate, Aldrich], TEMA[2-(trimethylsilyloxy)ethyl methacrylate, TCI], TMMA[(trimethylsilyl) methacrylate, Aldrich]를 활용하여 완전몰드로 SH-CL를 제조하였다. 함수율과 UV-VIS spectrophotomter 를 이용한 광투과율, TGA 분석을 통한 열적안정성 등의 물리적 특성과 FT-IR 분석을 통한 화학적 특성을 알아 보았다. 결과 : 동일한 양의 TRIM, TEMA, TMMA를 사용하여 제작한 SH-CL의 광투과율은 각각 92%, 86%, 80%로 측정되었으며, 함수율은 TRIM을 사용한 SH-CL에서 39.3%로 가장 높게 나타났다. FT-IR 분석 결과 세 종류의 SH-CL 모두 silicone monomer와 HEMA의 중합반응이 잘 이루어졌음을 확인할 수 있었고, TGA 분석을 통해 TRIM monomer의 sol-gel 반응 유무를 확인할 수 있었다. 결론 : Sol-gel 반응에 적합한 구조를 가지고 있어 상분리가 일어나지 않아 투명하고, Si에 극성 작용기인 methoxy기가 연결되어 있는 TRIM monomer가 SH-CL 제조에 적합한 구조임을 확인할 수 있었다.