Abstract Purpose : This study sought to find ways to improve awareness and ethics of opticians' code of ethics. Methods : A survey was conducted on 102 Korean opticians to investigate the awareness and performance satisfaction of the optician's code of ethics, as well as differences according to gender, age, education level, work experience, and workplace. Results : This study found no gender-based differences in opticians’ awareness and satisfaction with the code of ethics. However, age and education significantly influenced these factors, with higher levels observed among opticians in their 20s and 30s, particularly those in the early stages of their careers. Furthermore, a positive correlation was noted between education level and both awareness and satisfaction. The study revealed that opticians with volunteer experience exhibited higher awareness and satisfaction with the code of ethics than those without. This suggests that volunteering, which fosters professional identity and social responsibility, influences opticians’ ethical awareness. Additionally, groups with a strong interest in foreign languages and self-development demonstrated higher ethical awareness and satisfaction. Conclusion : This study underscores the need for enhanced ethical awareness among opticians. It advocates for the development of methods, case studies, and guidelines to address ethical issues not covered by the existing code, thereby revitalizing ethical practices in the profession. In addition, it is judged that active promotion and education on the code of ethics and professional ethics are necessary for the continuing education of opticians. Key words : Awareness, Code of ethics, Performance satisfaction

This research is conducted to analyze the compatibility of used monomers and produce the high functional hydrogel ophthalmic polymer containing silane and nanoparticles. VTMS (vinyltrimethoxysilane), TAVS [Triacetoxy(vinyl)silane] and cobalt oxide nanoparticles are used as additives for the basic combination of SilM (silicone monomer), MMA (methyl methacrylate) and MA (methyl acrylate). Also, the materials are copolymerized with EGDMA (ethylene glycol dimethacrylate) as cross-linking agent, AIBN (thermal polymerization initiator) as the initiator. It is judged that the lenses of all combinations are optically excellent and thus have good compatibility. Measurement of the optical and physical characteristics of the manufactured hydrophilic ophthalmic polymer are different in each case. Especially for TAVS, the addition of cobalt oxide nanoparticles increases the oxygen permeability. These materials are considered to create synergy, so they can be used in functional hydrogel ophthalmic lenses.

This research is carried out to analyze the effects of Styrene and PVP on the properties of silicone hydrogel lenses. Styrene group and PVP(Polyvinylpyrrolidone) are used as additives for a basic combination containing silicone monomer, TSMA(trimethylsilyl methacrylate) and DMA(n,n-dimethylacrylamide) added to the mix at ratios of 1~10 %. Silicone hydrogel lens is produced by cast-mold method. The polymerized lens sample is hydrated in a 0.9 % saline solution for 24 hours before its optical and physical characteristics are measured. Measurement of the physical characteristics of the produced material shows that the refractive index is 1.3682~1.4321, water content 77.11~45.73 %, visible light transmittance 95.14~88.20 %, and tensile strength 0.0652~0.3113 kgf. The results show a decrease of refractive index as the ratio of additives and water content decreases. The result of the stabilization test of polymerization show an increase of extractables along with increase of the ratio of additives, but the difference is not significant for all samples, so it can be judged that the stabilization of the polymer is maintained. Therefore, the additions of styrene and PVP should be taken into consideration for their effects on the physical properties of silicone hydrogel lens.

목 적：급성 뇌경색은 초기 진단이 매우 중요하지만, 일반 MRI 기법에서는 이를 발견하는 데 어려움이 있어 보편적으로 확산강조영상(diffusion weighted image; DWI) 기법이 사용되고 있다. 확산강조영상 검사에서는 질환이나 검사 부위에 따라 적절한 b값(b-value)을 적용하는 것이 중요하다. 이 중에서 높은 b-value를 요구하는 검사의 경우에는 정확한 진단을 위해서 추가적으로 낮은 b-value의 DWI 검사를 함께 시행하게 되고, 이로 인해 전체적인 검사시간이 길어지게 된다. 또한, 높은 값의 b-value로 검사를 하면 검사 장비에 따라서 전체적인 영상의 질이 현저히 저하될 수 있다. 이에 본 연구에서는 환자를 통해 획득하는 방식의 high b-value 확산강조영상(acquired DWI; aDWI)이 아닌 후처리 방식을 통해 재구성 한 high b-value 확산강조영상(computed DWI; cDWI)의 유용성에 대해 알아보고자 한다. 대상 및 방법：사용된 장비는 3.0T 초전도 자기공명영상장치(Magnetom Prisma, SIEMENS, Germany)와 64 channel Head & Neck coil을 사용하였다. 검사 방법은 뇌혈관 질환이 의심되어 DWI 검사를 시행한 환자들을 대상으로 한 임상 연구와 자체 제작한 팬텀을 이용한 팬텀 연구를 진행하였으며, 실제 획득한 high b-value aDWI과 후처리 방식을 통해 얻은 high b-value cDWI을 SIEMENS Syngo.via(Ver. VB10B)를 통해 각 부위의 신호를 측정한 후 상대적인 확산율(relative diffusion ratio)을 이용하여 비교 평가하였다. 통계적 분석은 두 변수 간의 Pearson's correlation coefficient을 통해 시행하였다. 결 과：임상 연구에서 aDWI의 b-value 2500 영상을 분석하였을 때, 경색이 의심되며 높은 신호 강도를 보이는 부위의 평균 확산율은 전두엽에서 73.95±4.81, 측두엽에서 75.51±5.19, 두정엽에서 68.74±6.13, 뇌교에서 70.72±5.84, 소뇌에서 62.9±7.12으로 나타났으며, cDWI에서는 전두엽에서 75.52±4.69, 측두엽에서 77.04±4.95, 두정엽에서 71.21±6.31, 뇌교에서 72.21±5.62, 소뇌에서 63.94±6.94으로 나타났다. 팬텀 연구에서는 0%를 기준으로 확산 제한이 일어나는 각 syringe의 평균 확산율을 측정하였을 때, aDWI 10%에서는 31.3±10.12, 20%에서는 52.2±17.37, 30%에서는 58.9±19.86, 40%에서는 65.7±19.86, 50%에서는 69.8±17.40로 측정되었고, cDWI에서는 10%에서 37.3±11.69, 20%에서 55.9±17.51, 30%에서 62.8±16.93, 40%에서 69.2±18.31, 50%에서 71.9±18.94로 측정되었다. Pearson’s 상관관계 분석에서는 두 변수 간에 강한 양의 상관관계를 보였으며 p값 0.05 이하로 통계적 유의함을 증명하였다. 결 론：임상 연구와 팬텀 연구에서 모두 aDWI와 cDWI의 확산율이 검사 간의 강한 양의 상관관계를 보이며, 평균확산율은 cDWI에서 약간 증가하였다. 이 결과는 확산이 잘 되는 조직과 확산 제한이 일어나는 조직 간의 신호 차이(확산율)가 aDWI 과 cDWI에서 유사하게 보인다는 것을 의미한다. 기존 획득 방식의 high b-value 확산강조영상과 비교하였을 때, 검사 후처리 방식으로 획득한 high b-value 영상의 경우 추가적인 검사시간이 필요하지 않으면서도 영상 신호의 저하 없이 만들 어 낼 수 있다. 이러한 강점들을 활용하면 후처리 방식의 확산강조영상 검사가 향후 high b-value를 요구하는 특정 질환 검사에서 환자에게 불편함을 주지 않으면서도 정확한 진단 결과를 도출하는 데 도움이 될 것이라 사료된다.

In this study, a multifunctional ophthalmic lens material with an electromagnetic shielding effect, high oxygen permeability, and high water content is tested, and its applicability is evaluated. Metal oxide nanoparticles are applied to the ophthalmic lens material for vision correction to shield harmful electromagnetic waves; the pyridine group is used to improve the antibacterial effect; and silicone substituted with urethane and acrylate is employed to increase the oxygen permeability and water content. In addition, multifunctional tinted ophthalmic lens materials are studied using lens materials with an excellent antibacterial effect (2,6-difluoropyridine, 2-fluoro-4-pyridinecarboxylic acid) and functional (UV protection, high wettability) lens materials (2,4-dihydroxy benzophenone, 2-hydroxy-4-(methacryloyloxy)benzophenone). To solve problems such as air bubbles generated during the polymerization process for the manufacturing and turbidity of the lens surface, polymerization conditions in which the defect rate is minimized are determined. The results show that the polymerization temperature and time are most appropriate when they are 110 oC and 40 minutes, respectively. The optimum injection amount of the polymerization solution is 350 ms. The turbid phenomenon that appears in lens processing is improved by 10 to 95% according to the test time and conditions.

This research is conducted to create a functional hydrogel ophthalmic lens containing nanoparticles. Carbon nanoparticles and PEGMEMA are used as additives for the basic combination of HEMA, MA, and MMA, and the materials are copolymerized with EGDMA as the cross-linking agent and AIBN as the thermal initiator. The hydrogel lens is produced using a cast-mold method, and the materials are thermally polymerized at 100 oC for an hour. The polymerized lens sample is hydrated in a 0.9% saline solution for 24 hours before the optical and physical characteristics of the lens are measured. The refractive index, water content, contact angle, light transmittance, and tensile strength are measured to evaluate the physical and optical characteristics of the hydrogel lens. The refractive index, water content, contact angle, UV-B light transmittance, UVA light transmittance, visible light transmittance, tensile strength and breaking strength of the hydrogel lens polymer are 1.4019~1.4281, 43.05~51.18 %, 31.95~68.61o, 21.69~58.11 %, 35.59~84.26 %, 45.85~88.06 %, 0.1075~0.1649 kgf and 0.1520~0.2250 kgf, respectively. The results demonstrate an increase in refractive index, tensile strength and breaking strength and a decrease in contact angle and light transmittance. Furthermore, the visible light transmissibility is significantly increased at PEG 10 %. It is clear that this material can be used for high-performance ophthalmic lenses with wettability, ultraviolet ray blocking effect, and tensile strength.

Purpose: This research was conducted to produce the functional hydrogel ophthalmic lens containing nanoparticles. Methods: Carbon nanoparticles and PEGMEMA were used as additives for the basic combination containing HEMA, MA, and MMA, and the material was copolymerized with EGDMA as the cross-linking agent and AIBN as the initiator. The hydrogel lens was produced by a cast-mold method, and the materials were thermally polymerized at 100° C for an hour. The polymerized lens sample was hydrated in a 0.9% saline for 24 hours before the optical and physical characteristics of the lens were measured. Results: The refractive index, water content, contact angle, light transmittance, and tensile strength were measured to evaluate the physical and optical characteristics of the hydrogel lens. The results showed that the refractive index, water content, contact angle, UV-B light transmittance, UV-A light transmittance, visible light transmittance and tensile strength of the hydrogel lens polymer was 1.4019~1.4281, 43.05~51.18%, 31.95~68.61°, 21.69~58.11%, 35.59~84.26%, 45.85~88.06% and 0.0657~0.1649kgf, respectively. It showed an increase of refractive index and tensile strength while decreased in contact angle and light transmittance. Conclusions: This material can be used for ophthalmic lenses with high performance of wettability, ultraviolet ray blocking effect, and tensile strength. Furthermore, the visible light transmissibility was significantly increased at PEG 10%.

목 적: 친수성 콘택트렌즈의 굴절력 측정 방식 중 하나인 Wet Cell 측정법에 대한 정확도를 확인하기 위 해 망원경식 렌즈미터를 사용하여 콘택트렌즈의 정점굴절력을 측정하였다. 방 법: Wet Cell 측정용 홀더는 현재 임상에서 주로 사용하고 있는 Poster Soft Contact Lens Wet Cell 제품을 사용하였으며, 국내 제조업체의 렌즈를 함수율은 38%, 45%, 58%로 구면굴절력은 -3.00D, -7.00D, -10.00D로 분류하여 각각 실험하였다. 결 과: 망원경식 렌즈미터를 사용하여 Wet Cell 방식으로 콘택트렌즈의 정점굴절력을 측정한 결과, -3.00D의 콘택트렌즈는 함수율 38%일 경우 -3.41D로 45%일 경우 –3.41D로 그리고 함수율 58%일 경우 -2.63D로 각각 측정되었다. -7.00D의 콘택트렌즈는 함수율 38%일 경우 –7.87D로 45%일 경우 –7.20D로 그리고 58%일 경우 -5.19D로 각각 측정되었다. 또한 -10.00D의 콘택트렌즈는 함수율 38%일 경우 –10.17D 로 45%일 경우 -10.60D로 58%일 경우 -7.33D로 각각 측정되었다. 결 론: 실험 결과, 함수율이 높을수록 Wet Cell 방식에 의한 측정값은 콘택트렌즈에 표기된 굴절력에 비 해 낮게 측정되는 경향을 나타내었다. 디옵터가 높아질수록 측정 정확도 역시 신뢰도가 낮은 것으로 나타났 다. Wet Cell 방식을 사용하여 망원경식 렌즈미터로 측정 시 함수율과 디옵터별로 정확도의 차이가 발생됨 을 알 수 있었다.

Purpose: The optical and physical characteristics of hydrogel soft contact lens polymerized with various hydroxy substituted acrylate material were evaluated. Methods: This study used HEMA(2-hydroxyethyl methacrylate), HEA(2-hydroxyethyl acrylate), HPMA(hydroxypropyl methacrylate) with the cross-linker EGDMA(ethylene glycol dimethacrylate) and the initiator AIBN(azobisisobutyronitrile) for copolymerization. The polymerization of the contact lens material was conducted through thermal polymerization in 100℃ for about 1 hours. Results: The polymer by using thermal polymerization process for hydrogel lens was produced and the physical properties showed that the water content of the sample containing HEMA, HEA and HPMA was in the average of 37.06%, 82.12% and 21.57%, respectively. And also, refractive index of the sample containing HEMA, HEA and HPMA was in the average of 1.4330, 1.3540 and 1.4649, respectively. In case of the optical properties of the sample, the result showed that the near-UV transmittance was 82.67%, 80.32% and 79.83%, and the visible transmittance was 89.72%, 88.24% and 86.89%, respectively. Conclusions: Consequently, polymerization of the hydroxy substituted acrylate material was more shorten the molecular length, increased water content and decreased the refractive index of the soft contact lens.

Purpose : Recently, the eye disease associated with ultraviolet radiation were reported. In this study, the UV-block hydrophilic soft contact lens using 2-ethylhexyl trans-4-methoxy-cinnamate were manufactured and the optical properties of copolymerized materials were measured. Methods: The basic hydrophilic soft contact lens material with addition of Dhb(2,4-dihydroxy benzophenone) 0.5% ~ 1.0%, Thb(2,4,4-trihydroxy benzophenone) 0.5% ~ 1.0% and Hmb(2-hydroxy-4-methoxy benzophenone) 0.5% ~ 1.0% respectively were polymerized and the hydrophilic soft contact lens were manufactured by cast mould method. The lenses were stored in a 0.9% NaCl normal saline for analysis. Results: In the measurement of DHB samples, the optical transmittance showed the UV-B transmittance of 2.1 ~ 4.3%, UV-A transmittance of 19.0 ~ 27.2% and visible transmittance 88.8 ~ 90.1%. And also, in the case of THB samples, the optical transmittance of UV-B, UV-A and visible transmittance was 2.0 ~ 2.4%, 13.6 ~ 18.8% and 89.5 ~ 90.9%, respectively. Also, in the case of HMB samples, the optical transmittance of UV-B, UV-A and visible transmittance was 4.0 ~ 12.3%, 22.5~37.2% and 87.9 ~ 89.2%, respectively. Conclusions: Based on the results of this study, 2-ethylhexyl trans-4-methoxy-cinnamate with benzophenone materials were suitable for use as a material to UV-block hydrophilic lens.

Purpose: This study evaluated the physical and optical characteristics of hydrophilic contact lens polymerized with addition of 1-vinylimidazole in the basic hydrogel contact lens material, and in particular, the utility of 1-vinylimidazole as a contact lens material for ophthalmologic devices was investigated. Methods: This study used 1-vinylimidazole with the cross-linker EGDMA (ethylene glycol dimethacrylate), HEMA (2-hydroxyethyl methacrylate) and the initiator AIBN (azobisisobutyronitrile) for copolymerization. The polymerization of the contact lens material was conducted through thermal polymerization in 100°C for about 40 mins. To produce the high functional contact lenses, a cast mould method was used. Results: The physical properties of the hydrogel ophthalmic material were investigated by measuring the average value of refractive index, water content and optical transmittance. The refractive index of 1.4330~1.4408, water content of 36.10~38.59%, UV-A transmittance of 90.0~72.2% and UV-B transmittance of 88.6%~64.2% and visible ray transmittance of 89.2~91.8% were obtained. The transmittance for visible light was over 89% in all combinations with 1-vinylimidazole and the transmittance for UV reduced up to a certain level in certain combinations with 1-vinylimidazole. Conclusions: Based on the results of this study, the produced copolymer can be estimated to be suitable for use as ophthalmic lens material for UV- blocking effects.

목 적 : 본 연구는 기존 콘택트렌즈 홀더와 소프트 콘택트렌즈를 보다 쉽고 안정적으로 장착할 수 있도록 설계한 개선된 콘택트렌즈 전용홀더를 사용하여 다양한 디옵터와 함수율을 가진 소프트 콘택트렌즈의 굴절력을 측정하고 정확도를 평가하였다. 또한 측정 시간경과에 따른 굴절력의 변화를 분석하였다. 방 법 : 실험에 사용한 소프트 콘택트렌즈의 함수율은 각각 38%, 43%, 58%의 렌즈를 사용하였으며, 굴절력에 따라 -3.000D, -7.000D, -10.000D로 분류하여 실험하였다. 또한 기존 콘택트렌즈 홀더와 개선된 콘택트렌즈 홀더를 사용하여 자동렌즈미터로 굴절력을 측정하여 신뢰도를 분석하였다. 결 과 : 기존 콘택트렌즈 홀더를 사용한 경우 -3.000D는 -3.129D로 측정되었으며, -7.000D는 -7.036D, -10.000D는 -10.266D로 각각 측정되었다. 개선된 콘택트렌즈 홀더를 사용한 경우 -3.000D는 -3.007D로 측정되었으며, -7.000D는 -6.988D, -10.000D는 -9.944D로 각각 측정되었다. 모든 종류의 콘택트렌즈에서 개선된 콘택트렌즈 홀더를 사용한 방법이 기존 콘택트렌즈 홀더를 사용한 방법보다 더 정확한 측정값을 나타내었다. 결 론 : 소프트 콘택트렌즈의 굴절력 측정에 있어 개선된 콘택트렌즈 홀더를 사용한 방법이 기존 콘택트렌즈 홀더를 사용한 방법보다 더 정확한 측정값을 나타내었으며, 콘택트렌즈의 굴절력과 함수율이 높을수록 전체적으로 낮은 정확도를 나타내었다.

1970년대에 여러 연구자가 시제품 시험장비를 가지고 인발시험을 실시하였으며, 인발시험은 콘크리트 강도를 결정하는 신뢰할 만 한 비파괴검사 방법(NDT)으로 입증되었다. 우리는 고강도 콘크리트 강도를 추정하기 위하여 직경 10 mm볼트에 홈이 파인 파단형 인발 볼트 와 인발너트, 그리고 로드셀이 필요 없는 오일 유압펌프를 포함한 간이 인발시험법을 제안하였다. 저비용, 간편성 및 편의성을 갖는 간이인발 시험의 이점을 검증하기 위하여, 30 MPa 및 50 MPa 급 두가지 유형의 콘크리트로 제작된 4개의 모의벽체를 대상으로 로드셀을 장착한 간이인 발시험을 사용하여 인발시험을 실시하였다. 인발하중과 콘크리트 압축강도는 재령 7일까지는 매일, 그리고 14일, 21일, 28일에 측정되었다. 시 험결과 인발하중과 콘크리트 압축강도는 매우 밀접한 상관관계를 보여주었으며 따라서 인발하중이 현장에서 구조물의 고강도 콘크리트 강도 를 평가할 수 있다는 것을 확인할 수 있었다. 파단형 인발볼트 직경과 콘크리트 강도와의 관계식으로 y=0.05x+3.79(x=콘크리트 압축강도, y=파단형 인발볼트 직경)이 도출되었으며 결정계수는 0.88로 나타났다.