• The korean journal of orthodontics
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• v.40 no.1
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• pp.40-49
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• 2010

Objective: The aim of this research was to evaluate the mechanical properties (MP) and degree of the phase transformation (PT) of martensitic (M-NiTi), austenitic (A-NiTi) and thermodynamic nickel-titanium wire (T-NiTi). Methods: The samples consisted of $0.016\;{\times}\;0.022$ inch M-NiTi (Nitinol Classic, NC), A-NiTi (Optimalloy, OPTI) and T-NiTi (Neo-Sentalloy, NEO). Differential scanning calorimetry (DSC), three-point bending test, X-ray diffraction (XRD), and microstructure examination were used. Statistical evaluation was undertaken using ANOVA test. Results: In DSC analysis, OPTI and NEO showed two peaks in the heating curves and one peak in the cooling curves. However, NC revealed one single broad and weak peak in the heating and cooling curves. Austenite finishing ($A_f$) temperatures were $19.7^{\circ}C$ for OPTI, $24.6^{\circ}C$ for NEO and $52.4^{\circ}C$ for NC. In the three-point bending test, residual deflection was observed for NC, OPTI and NEO. The load ranges of NC and OPTI were broader and higher than NEO. XRD and microstructure analyses showed that OPTI and NEO had a mixture of martensite and austenite at temperatures below Martensite finishing ($M_f$). NEO and OPTI showed improved MP and PT behavior than NC. Conclusions: The mechanical and thermal behaviors of NiTi wire cannot be completely explained by the expected degree of PT because of complicated martensite variants and independent PT induced by heat and stress.

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.294-295
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• 2003

OCT(Optical Coherence Tomography) 기술은 기본적으로 낮은 가간섭성 광원의 빛을 대상물에 주사하여 피대상물의 내부구조에 따른 각종 광학정 수치를 높은 수직 분해능으로 깊이별로 얻어낼 수 있는 기술이다. 현재 많은 생체 연구그룹에서 OCT의 개발과 응용에 대해 적극적인 연구가 진행 중에 있으며, 그 적용분야를 확대하고 있는 추세이다. OCT에 관련된 대표적인 연구분야로서 조직의 미세 단층영상, 혈류 가시화 및 각종 생체조직에 따른 복굴절율 변화 측정 등이 있다.(중략)

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.5
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• pp.421-426
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• 2017

In this study, we propose a method for predicting the mechanical properties of the printed circuit board (PCB) that has transversely isotropic characteristics. Unlike the isotropic material, there is no specific test standard for acquisition of the transversely isotropic properties. In addition, common material test methods are not readily applicable to that type of laminated thin plate. Utilizing the natural frequency obtained by a modal test and the sizing optimization technique provided in $OptiStruct^{(R)}$, the mechanical properties of a PCB were derived to minimize the difference between test and analysis results. In addition, the validity of the predicted mechanical properties was confirmed by the MAC (Modal Assurance Criteria) value of each of the compared mode shapes. This proposed approach is expected to be extended to the structural analysis for the design verification of the top product that includes a PCB.

• Fashion & Textile Research Journal
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• v.20 no.6
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• pp.690-703
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• 2018

The purpose of this study is to help user understand the basic principles and interfaces of each program, and to provide a base material for the development of more efficient apparel CAD systems to compensate for each program's shortcomings by comparing the function of three apparel CAD systems: Yuka CAD, Opti-tex, and Style CAD. For this purpose, the skirt waistband and sleeve armhole line creation process were selected based on these two criteria. 1) There is a big difference between principle and method between CAD systems. 2) When CAD system is used rather than paper drawing process, the process is shortened and convenience is high. In this study, pros and cons and supplement point of each CAD system are suggested by comparing the functions of the CAD system performing the selected drafting process by four criteria: icon, key, method, and characteristic point. As a result of the study, it was confirmed that the three CAD systems differ in the basic principle and interface environment. As a result of analyzing the skirt waistband method function, it was confirmed that the band line is formed directly on the outline of the skirt and the band dart recognition function is the most efficient function and as a result of the analyzing the sleeve armhole line method function, it was confirmed that the curve generation function using the shape of the actual curve measure and the length adjustment function through the automation of the dimension calculation is the most efficient function.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.1
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• pp.33-41
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• 2011

The objective of this study was to compare the shear bond strengths of five dentin adhesive systems cured with three different light curing sources. Seventy five noncarious permanent teeth were collected and stored in an 0.1% thymol solution at room temperature after extraction. The tested adhesives were: Adper Scotchbond Multi-purpose Plus Adhesive (SM) Adper Single bond 2 (SB), Clearfil SE Bond (SE), Adper Prompt L-Pop (PL), G-Bond (GB). And three light curing unit systems were used: Elipar Free light 2(LED), OptiLux 501 (Halogen), Flipo (PAC). For the shear bonding test, the labial and lingual surfaces of permanent teeth were used. To obtain a flat dentin surface, the labial and lingual surfaces of the teeth were sanded on SiO2 with number 600 grit and then divided into 15 groups of 10 surfaces each. All samples were theromocycled in water $5^{\circ}C$ and $55^{\circ}C$ for 1000 cycles. The results were as follows: 1. When cured with Freelight 2, the shear bond strength of SM was significantly higher than that of PL, GB (p<0.05), whereas no significant difference was found among those of any other bonding agents. 2. When cured with Optilux 501, the shear bond strength of SM was significantly higher than those of any other bonding agents (p<0.05), whereas no singnificant difference was found among those of andy other bonding agents. 3. When cured with Flipo, the shear bond strength of SM was significantly higher than those of SB, SE, GB (p<0.05), whereas no significant differences was found among those of any other bonding agents. 4. For comparison according to three different light cure unit system, except SB and GB, each three dentin bonding agents showed no significant difference. For SB, only Freelight 2 was significantly higher than the others, with no significant difference between Optilux 501 and Flip. For GB, Statistically significant difference was found only between Freelight and Flipo.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.1
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• pp.21-26
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• 1991

the Bacillus subtilis LY-353 which secretes the protease isolated from seafoods. The opti-mum culture condition for production of protease from B. subtilis LY-353 was as follows ; tem-perature 35$^{\circ}C$ pH 7.5 salt concentration 1.0% The purification steps involved ammonium sulfate fractionation DEAE-Sephadex A-50 column chromatography and Sephadex G-100 gel filtration A 7.33 fold purification and 6.55 yield of protease was obtained from culture broth, The optimum pH and temperature for the enzyme action were pH7.5 and 55$^{\circ}C$ respecti-bely.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.3
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• pp.19-25
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• 2007

It was studied how using soft contact lens multi-purpose solution (MPS), often used for medical treatment, effects the inhibition on cell growth, and how using the MPS demages eye cells, on rabbit eye's corneal epithelium and endothelium tissue. $ReNu^{(R)}$ (Baush & Lomb, USA), Opti-free $express^{(R)}$ (Alcon, USA), Free-sol $plus^{(R)}$ (Hanamedicon, Korea) were used as MPS. After culturing Clone 1-5C-4 cell lines (Human conjunctival cell lines), cell growth inhibition rate was measured by MIT assay. By making Hematoxylin and Eosin stain specimen, the morphology was observed by optical microscope. In the In vivo experiment, 9 white rabbit eyes (18 eyes) were classified into 3 groups. The experiment group is left eyes (9 eyes) of rabbit, and MPS were dropped; however the control group, the right eyes (9 eyes), were only used a saline solution without a preservatives. After the dropping within the period, the cornea surface of rabbit endothelium tissue was observed using scanning electron microscopy (SEM).

• Proceedings of the KIEE Conference
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• 1998.11c
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• pp.841-843
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• 1998

The fiat fluorescent lamp(FFL) can be used to the LCD bat]flighting. In order to evaluate the discharge characteristics of FFL firing voltage, discharge current, luminance and CIE chromaticity with frequency were measured. The experimental results show that firing voltage decreased with increasing the frequency, discharge current increased with increasing the frequency. Luminance of FFL using Xe gas shown $2700\;cd/m^2$ in 700V rms, 80 kHz.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.3
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• pp.224-228
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• 1990

Cabbage contained high peroxidase activity among tested plant sources. The cabbage peroxi-dase can replace horseradish peroxidase to assay glucose with glucose oxidase. The amount of glucose can be determined quantitatively by glucose oxidase-cabbage peroxidase. The opti-mum pH and temperature for enzymatic glucose determination by glucose oxidase-cabbage peroxidase were 6.0 and 35-45$^{\circ}C$ respectively. The glucose assay was inhibited by addition of various metal salts such as mercuric chloride lead acetate silver nitrate ammonium molyb-date sodium tunstate and cupric sulfate. The relationship between absorbance and amount of glucose was linear up to 8.33 mM glucose in the assay mixture under the assay conditions.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.3
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• pp.343-347
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• 1998

The objective of this study is to manufacture the low temperature waterless container that is compact and low cost for a live fish transportation. Using the low temperature water container, it makes observations on the optimal conditions such as the amount of dissolved oxygen, total ammonia and nitrite in seawater for determining the survival rate of live fish in short and long-term transportation. Using a sole as a live fish, the temperatures of $0^{\circ}C$, 3$^{\circ}C$, 5$^{\circ}C$, 7$^{\circ}C$, 15$^{\circ}C$ were controled for there effects. The results of this investigation show that as the seawater temperature increased, the amount of oxygen decreased and there was a low temperature shock below 3$^{\circ}C$. It was observed that the fish was died with 30$m\ell/\ell$of ammonia. The optimal temperature is about 5$^{\circ}C$ for live fish transportation to maintain best survival rate.