• 한국수소및신에너지학회논문집
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• 제25권2호
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• pp.145-150
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• 2014

This study investigates the preparation of anti-reflective (AR) coating film to improve the efficiency of solar cell. The AR coating film was successfully obtained by dip-coating with AR coatings prepared by sol-gel method. Fluoroalkylsilane was additionally introduced into the coatings to give the self-cleaning effect of AR coating film. We performed the abrasion test, pencil scratch hardness test and cross-cut test to identify the mechanical strength of AR coating film. As the results, the transmittance of AR coating films with 9.07, 18.13 and 27.20 of IPA/MTMS molar ratios were 93.1, 93.6 and 95.3%, respectively. The water contact angle and transmittance of AR coating film increased by the introduction of hydrophobicity. The prepared AR coating film shows the high level of abrasion, hardness and adhesion. The IPA/MTMS molar ratio of 27.20 and the withdrawing speed range of 0.20 ~ 0.28cm/sec are the optimal coating condition in terms of the transmittance and mechanical strength of AR coating film.

• 한국세라믹학회지
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• 제32권1호
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• pp.95-105
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• 1995

Ceria(CeO2) stabilized zirconia(CeSZ) sol was synthesized with zirconium n-butoxide Zr(OC4H9)4 and cerium nitrate hexahydrate Ce(NO3)3.6H2O as precursors and ethylacetoacetate(EAcAc) as a chelating agent under atmosphere. CeSZ films were deposited on AISI 304 stainless steel using the prepared polymeric sol by dipcoating and the coating characteristics were investigated by XRD, ellipsometry, scratch test and SEM. The CeSZ film began to crystallize from amorphous to tetragonal phase at 40$0^{\circ}C$ and it was not converted into monoclinic phase up to 100$0^{\circ}C$ by the addition of 16mol% CeO2 as a stabilizer which could suppress phase transformation of zirconia. The CeSZ films were prepared by varying the EAcAc contents and the cncentration of CeSZ sol and measured the thickness and refractive index. From these results, it was found that the EAcAc contents and concentration of CeSZ coating sol evidently affect the densification of CeSZ film. The CeSZ film coated with 0.4M CeSZ sol and heat-treated at $600^{\circ}C$ for 10min had thickness of 50nm and 17% porosity. The CeSZ film on 304 stainless steel effectively acted as a protective layer against oxidation up to 80$0^{\circ}C$ and had superior corrosion resistance in 25% H2SO4 solution for 4.5 hrs.

• 한국신뢰성학회지:신뢰성응용연구
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• 제14권1호
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• pp.11-19
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• 2014

A colloidal silica slurry has been manufactured by mixing nano silica powders having different grain size to improve the reliability of Sapphire wafer CMP process. The main reliability problem of CMP process such as the breaking of wafer can be prevented by reducing the size of particles in a slurry. While existing commercial colloidal silica slurries are usually made of single grain size silica powder of about 120nm, in the present study 40nm and 100nm silica powders are mixed to achieve a similar removal rate. The new colloidal silica slurry showed wafer removal rate of $3.04{\mu}m/120min$ while that of a commercial colloidal silica slurry was $3.03{\mu}m/120min$. The roughness was less than $4{\AA}$ and scratch was 0. It is also expected that the reduction of the size of nano silica particles can improve the dispersion stability and prolong the useful life of the slurry.

• 대한기계학회논문집
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• 제8권3호
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• pp.195-200
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• 1984

본 연구에서는 SUS 304강의 상온하의 평골재 표면에 발생. 성장하는 미소표면 피로균열의 거동을 파괴역학적 관점과 수법으로 정량적으로 조사하려는 연구의 일환 이다.

• 한국산업융합학회 논문집
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• 제16권4호
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• pp.113-117
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• 2013

This paper describes a new technology to develop the character recognition technology based on pattern recognition for non-contacting inspection optical lens slant or precision parts, and including external form state of lens or electronic parts for the performance verification, this development can achieve badness finding. And, establish to existing reflex data because inputting surface badness degree of scratch's standard specification condition directly, and error designed to distinguish from product more than schedule error to badness product by normalcy product within schedule extent after calculate the error comparing actuality measurement reflex data and standard reflex data mutually. Developed system to smallest 1 pixel unit though measuring is possible 1 pixel as $37{\mu}m{\times}37{\mu}m$ ($0.1369{\times}10-4mm^2$) the accuracy to $1.5{\times}10-4mm$ minutely measuring is possible performance verification and trust ability through an experiment prove.

• 한국한의학연구원논문집
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• 제16권3호
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• pp.115-121
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• 2010

Objectives : Quality control of the needle tips and prevention of pollutions are important factor for safe and effective acupuncture treatment. Ear acupuncture needle is made by 3 companies in Korea, and used to treat for obesity or smoking in clinic frequently, but the Korean industrial Standard is proposed most recently. In spite of the importance, there has been little study about that. Moreover, there was no study about ear acupuncture needle. Methods : We investigated the current condition of needle shape and pollution about the tips and body of the ear acupuncture needle under the stereoscopic microscope. Samples are selected 100 pieces from 300 pieces randomly in each company. Results : The substandard needles are classified into four groups and counted 1. Normal condition (55.3%), 2. Scratch on the surface (14.0%), 3. Malformation of tips (19.3%), 4. Pollution of body (4.3%), 5. Multiple Substandard (7.0%). In the case of including type 2 as a standard needle, normal rate of A company was 81% when B was 76%, and C was 51%. Conclusion : The substandard ear acupuncture needles can induce local side effects such as needling pain or itching. Furthermore, it can disturb the proper effect of acupuncture treatment. We hope that this study can help to improvequality of ear acupuncture and reduce substandard rate for safe and effective ear acupuncture treatment.

• 한국안광학회지
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• 제8권2호
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• pp.25-29
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• 2003

자외선과 전자파를 동시에 차단하는 선글라스렌즈를 제작하기 위하여 유리가판 위에 자성재료인 페라이트에 Ni를 여러 가지 조성비로 첨가한 니켈페라이트 박막 $Ni_xFe_{3-x}O_4$을 페라이트 도금법으로 제작하였다. 이들은 모두 스피넬 구조의 단일상임을 확인할 수 있었으며 육안으로 관찰할 때 거울면과 같은 광택을 가졌으며, 손톱으로 긁었을 때 흠집이 생기지 않는 강도를 보였다. 니켈페라이트는 400nm 부근에서부터 급격히 투과율이 떨어져 자외선을 차단하는데 효과적인 양상을 보이고 있으며 그 중에서 x = 0.09의 Ni 조성비가 자외선 차단효과가 가장 좋은 깃으로 나타났다. 이는 타사제품과 비교하여 자외선 차단효과는 크게 떨어지지 않으므로, 전자파 차단효과가 있는 $Ni_xFe_{3-x}O_4$ 페라이트를 코팅한 선글라스를 착용함으로서 유해전자파와 자외선을 동시에 차단하는 효과를 얻을 수 있을 것이다.

• 한국식품저장유통학회지
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• 제30권3호
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• pp.483-491
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• 2023

본 연구에서는 제주도에서 자생한 병풀을 수집해 스마트팜과 노지에서 재배하고 이를 이용하여 주요성분 및 각질형성세포 활성화에 미치는 영향을 확인 및 비교하였다. 스마트팜 재배 병풀과 노지 재배 병풀의 유전자 확인을 통한 종 분석을 위해, 핵 속의 ITS DNA와 엽록체의 psbA-H DNA를 증폭하여 염기서열을 분석한 후 NCBI 유전자 은행에서 보고된 식물들의 DNA와 비교하였다. 스마트팜 재배 병풀과 노지 재배 병풀의 ITS DNA 염기서열은 유전자 은행의 MH768338.1번 Centella asiatica와 일치하고 엽록체 psbA-H DNA 또한 유전자 은행의 JQ425422.1번 C. asiatica와 일치하였다. 스마트팜 재배 병풀추출물(SEE)과 노지 재배 병풀추출물(FEE)의 triterpene은 HPLC에 의해 분석되었으며, SEE의 madecassoside, asiaticoside, madecassic acid, asiatic acid 함량은 각각 59.31±0.94 mg/g, 46.38±2.26 mg/g, 6.21±1.47 mg/g, 7.04±1.93 mg/g으로 분석되었다. 반면, FEE는 각각 24.38±1.31 mg/g, 21.28±1.44 mg/g, 3.11±1.05 mg/g, 5.40±1.26 mg/g으로 측정되어 SEE가 FEE보다 더 높은 triterpene을 갖는 것이 확인되었다. 사람 각질형성세포에 대한 SEE와 FEE의 독성은 실험된 농도 내에서 관찰되지 않았으며, 스크래치가 유발된 세포 내 회복은 SEE가 FEE보다 더 높은 회복능을 보였다. 따라서, 본 실험 결과 triterpene 함량이 더 높은 스마트팜 재배 병풀이 건강기능식품 소재로서 더 효과적이라고 판단된다.

• 한국보건간호학회지
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• 제24권1호
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• pp.39-48
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• 2010

Purpose: To examine the effects of a 36-week resistance training program on body composition, fitness and blood lipid profiles in the obese elderly. Method: fourteen subjects were assigned into the resistance training group. The 12-16 exercise sessions were performed for 60min with 15-25 repetitions twice per week for 36 weeks. Data were analyzed by paired t-test with SPSS version 12.0 for Windows. Results: Significant changes were evident in weight (t=5.983, p<.001), body mass index (t=5.922, p<.001), % body fat (t=3.480, p=.004), and fat free mass (t=-2.592, p=.022). Concerning exercises, no significance was noted for back scratch (t=-1.814, p=.093), but were for 2-min step (t=-3.075, p=.009), arm curl (t=-2.223, p=.045), chair stand (t=-3.671, p=.003), chair sit and reach (t=-2.508, p=.026), and 8-ft up and go (t=5.545, p<.001). No significant changes were evident in total cholesterol (t=1.189, p=.279), and total glucose (t=0.689, p=.517), while the change in high-density lipoprotein was significant (t=3.535, p=.012). Conclusion: The 36-week resistance training program enhanced body composition and physical fitness, but not blood lipid profiles in obese elderly subjects.

• 한국학교보건학회지
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• 제2권1호
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• pp.131-146
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• 1989

This study was conducted for the development of recording system of students' health problems, and for the application of International Classification of Health Problem in Primary Care(ICHPPC) as a tool of morbidity classification in school health care. The data were collected from 12th of September to 24th of September in 1988. The objects were composed of health problems written by 10 school nurses who take service in the elementary school. The results were as follows: 1. The features of students' health problmes. The health problems of students were 68 problems from the total numbers of 361 codes of ICHPPC. The 93.4% of health problems was contained in 20 descriptive diagnoses and 97.0% was contained in 30 descriptive diagnoses. According to frequency of main health problems, There were abrasion, scratch and blister(26.7%); disorder of stomach function, other disease of stomach and duodenum (20.4%); headache(10.6%); bruise and contusion (5.3%); acute URI (5.0%); laceration and open wound(4.6%); Insect bite and sting(4.0%); epistaxis(3.4%): abdominal pain(2.6%): superficial tissue(1.7%). Out of all health problems, Category 17(accident, injury and poisoning was 44.7%. and Category 9(digestive system Disease) was 22.2%. 2. Applicability of ICHPPC by the school nurses. School nurses used 68 codes, among the total number of 361 codes from ICHPPC. According to ICHPPC method, school nurses can classified more diverse health problems systematically and objectively than that in other studies on school nurses activities. ICHPPC was found as a useful and applicable tool of morbidity classification in the practice of school nurses.