• 한국지반공학회지:지반
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• 제7권3호
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• pp.21-32
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• 1991

본 연구에서는 복합 zone을 가진 rockfill dam성토 재료의 강도정수들과 core zone에서의 간극 수압의 불확정성을 고려할 수 있도록, 성토 재료의 공간적인 변화의 불확실성, 시료수의 제한에 의 한 불확정성에 실험실 결과와 현장 결과와의 차이에 따른 model 오차의 영향을 고려한 종합적인 설계변수들의 불확정성을 규명하였으며 core zone의 간극수압과 rockfill zone의 내부 마찰각을 bayeg 이론을 이용하여 불확정성을 Updating할 수 있는 방법을 제시하였다. 사면 안정 해석에서 시공직후 상, 하류, 만수위 상, 하류 수위, 급강하 시의 2차원 사면안정해석 과 end effect 영향을 고려한 3차원사면 안정해석을 하였다. 본 목적을 위하여 복합 zone을 가진 rockfill dam의 사면 안정해석에서 end effect의 영향을 고려한 3차원 사면안정해석 Program인 "ESTABL"을 개발하였으며, 파괴 사면의 강도정수와 간극수압의 변동계수를 구하는 프로그램 "COV", 복합 zone사면 안전율의 변동계수를 구하는 프로그램 "PCOV"을 개발하였다. 사면안정해석 결과 3차원안전율이 2차원안전율보다 약 200A정도 크게 나타나므로 end restraint 효과가 상당히 큼을 알 수 있다. 3차원사면안정은 근본적으로 system reliability 문제이 므로 안전율의 평균간보다 그 불확정성이 더 큰 영향을 미침을 보여준다. 또한 기초설계 치로 설계 를 마친후 시공중 혹은 추가로 각종 계측치가 있을 때 updating 이론을 이용하여 신뢰도를 증가시 킬 수 있음을 보여주며 강도계수의 변화에 의한 파괴확률의 변화는 점착력의 불확정성이 내부마찰 각의 불확정성보다 민감하게 영향을 미침을 보여준다.찰 각의 불확정성보다 민감하게 영향을 미침을 보여준다.

• 구강회복응용과학지
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• 제23권2호
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• pp.157-170
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• 2007

Purpose: This investigation was designed to determine the translucency and color stability of various core ceramics for all-ceramic restoration using the CIE $L^*a^*b^*$ system. Material and Methods: IPS e.max Press ceramic(Ivoclar-Vivadent, Liechtenstein), $LAVA^{TM}$ All Ceramic(3M-Espe, Germany), Cercon Smart Ceramic(Dentsply, Germany), and Z-match Ceramic(DentAim, Korea) were used for this study. For the specimens of zirconia oxide ceramics, the as-sintered cylindrical blanks($11.0{\times}25.0mm$) were machined into the shape of a disk(0.4, 0.8, 1.5 mm in thickness, 10 mm in diameters) with a diamond grind machine. The IPS e.max Press specimens ($0.8{\times}10mm$) were fabricated using the "lost wax" technique. CIE $L^*a^*b^*$ coordinates and light transmission were recorded for each specimen with a spectrophotometer(CM-2600d, Minolta, Japan). Color differences were calculated using the equation, ${\Delta}E^*ab=[({\Delta}L^*)2+({\Delta}a^*)2+({\Delta}b^*)2]1/2$. Results: The results were obtained as follows: 1. The most translucent group was IPS e.max Press ceramic that is a glass-ceramic, and $Lava^{TM}$ and Z-match ceramic were more translucent than Cercon Smart ceramic in zirconia ceramic group. 2. In the all groups, there was no significant translucent change after 6 times heat-treatments required to make a final restoration. 3. Colored zirconia was showed more yellowish and dark than uncolored zirconia. 4. After heat-pressing, IPS e.max Press ceramic was showed high ${\Delta}E^*ab$ value(4.1 of eM1, 6.8 of eM2) that means to be more whiter than before heat-pressing. However, there was no color change after additive heat treatments for final restoration. 5. In the colored zirconia groups, there was no significant color change after some heat-treatments required to make a final restoration.

• Journal of the Optical Society of Korea
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• 제17권2호
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• pp.117-129
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• 2013

We briefly review the recent progress in passively mode-locked fiber lasers (PMLFLs) based on semiconductor saturable absorber mirrors (SESAMs) and discuss the detailed characterization of a SESAM-based, passively mode-locked erbium-doped fiber (EDF) laser operating in the 1.5-${\mu}m$ spectral range for various configurations. A simple and compact design of the laser cavity enables the PMLFL to generate either femtosecond or wavelength-tunable picosecond pulses with high stability as the intra-cavity filtering method is altered. All the cavities investigated in our experiments present self-starting, continuous-wave mode-locking with no Q-switching instabilities. The excellent stability of the source eventually enables the wavelength-tunable PMLFL to be used as a master oscillator for a power-amplifier source based on a large-core EDF, generating picosecond pulses of >10-kW peak power and >100-nJ pulse energy.

• Bulletin of the Korean Chemical Society
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• 제24권4호
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• pp.499-503
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• 2003

Encapsulation of L-ascorbic acid (vitamin C) within a bio-compatible layered inorganic material was achieved by coprecipitation reaction, in which the layered inorganic lattice and its intercalate of vitamin C are simultaneously formed. The nano-meter sized powders of vitamin C intercalate thus prepared was again encapsulated with silica nano-sol to form a nanoporous shell structure. This ternary nanohybrid of vitamin Clayered inorganic core-$SiO_2$ shell exhibited an enhanced storage stability and a sustained releasing of vitamin C. Furthermore, the nano-encapsulation of vitamin C with inorganic mineral was very helpful in delivering vitamin C molecules into skin through stratum corneum, facilitating transdermal penetration of vitamin C in topical application.

• 한국염색가공학회지
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• 제19권1호
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• pp.37-44
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• 2007

In this study, for textile use, the octadecane of phase change materials(PCM) was encapsulated in several micro-diameter shell which prevents leakage of the material during its liquid phase. Microencapsulated PCM(PM) was prepared with the different weight ratio of core material to wall material and by interfacial polymerization methods using polyurea as shell material. Phase stability for O/W emulsion of PCM and PVA aq. (PE) was evaluated by Turbiscan Lab. The capsule formation win identified using FT-IR. Physical properties of microcapsules including diameter, particle distribution, morphology were investigated. Thermal transport properties of suede treated with PM(SPM) were determined by KES-F7 system.

• 한국자기공명학회논문지
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• 제20권1호
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• pp.22-26
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• 2016

FANCJ is a DNA helicase which contributes genome stability by resolving G-quadruplex DNA from 5' to 3' direction. In addition to main ATPase helicase core, FANCJ has the protein binding region at its C-terminal part. BRCA1 and BLM are the binding partner of FANCJ and these protein-protein interactions contribute genomic stability and the proper response to replication stress. As the first attempt for studying FANCJ-BLM interaction, we prepared BLM binding region of FANCJ and characterized with CD and NMR spectroscopy. FANCJ (881-941) with N-ter 6xHis was purified as the oligomer. Secondary structure prediction based on CD data revealed that FANCJ (881-941) composed with ${\beta}$ sheet, turn and coils.$^1H-^{15}N$ HSQC spectra showed nonhomogeneous peak intensities with less number of peaks comparing than the number of amino acids in the construct. It indicated that optimization should be necessary for detailed further structural studies.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.72-77
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• 2003

The study tasked by Ryan Lode Mines, Inc. involved analysis of pit slope stability for two future pits, Ryan and Curlew. A geological discontinuity survey and groundwater information were obtained through a field program. Twenty core logs containing geotechnical information were used for rock mass classification. The kinematic analysis was performed based on a friction angle (${\Phi}=35^{\circ}$), the distribution of geological structures, and a dry slope condition. Factors of safety of pit slopes in two future mines were determined using the limit equilibrium method. The mine slopes and benches designed by Mine Development Associates (MDA) were analyzed. The analysis indicated that both pits should have an overall safety factor above 1.0, provided the slopes are kept dry. However, slopes in both pits exceeding 91.4 m (300 ft) high will become critical, when water fills the cracks and discontinuities.

• Journal of the Optical Society of Korea
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• 제6권1호
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• pp.5-12
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• 2002

A novel interrogation scheme to detect fine Bragg wavelength shift using a long period fiber grating pair with erbium-doped fiber inserted between the two gratings is reported. The technique is shown to feature high resolution and much more immunity to temperature perturbation compared to the conventioned Mach-Zehnder interferometer demodulation system. For quasi-static strain measurement, this approach provides high wavelength resolution of 0.05 pm that corresponds to 41.7 ne in strain and $3.8 $\times$ 10^{-3}$$^{\circ}C$ in temperature. This interrogation system is also employed in dynamic measurement to obtain the minimum detectable strain perturbation of ~ 8.76 ne/H $z^{{\frac}{1}{2}}$ at 100 Hz. Moreover, this interrogation system has prominent thermal stability. This thermal stability comes from the fact that two arms of the interferometer, the core and cladding in erbium-doped fiber, are exposed to nearly the same environment .

• Journal of Electrochemical Science and Technology
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• 제7권3호
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• pp.206-213
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• 2016

Transition metal oxide-based electrodes for lithium ion batteries have recently attracted much attention because of their high theoretical capacity. Here we report the electrochemical behavior of cobalt oxide nanorods as anodes, prepared by a template-free, one-step electrochemical deposition of cobalt nanorods, followed by an oxidation process. The as-deposited cobalt has a slightly convex columnar structure, and controlled thermal oxidation produces cobalt oxides of different Co/O ratios, while the original shape is largely preserved. As an anode in a rechargeable lithium battery, the Co/O ratio has a strong effect on initial capacity and cycling stability. In particular, the one-dimensional Co@Co_xO_y core shell structure obtained from a mild heat-treatment results in superior cycling stability.

• 대한심미치과학회지
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• 제13권1호
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• pp.31-39
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• 2004

For the prosthodontic results which are compatible with esthetics to be fulfilled, the first prerequisite would be periodontal intervention and stability, the second one may be functional competency and the ultimate goal should be ascribed to esthetic considerations. Other words, esthetic dentistry is a whole entity which encompasses the biological stability of the periodontium, physical accuracy of the prosthodontic structure and finally, the beauty which can be found in natural dentition. It also implies the harmonized lip line which reveals the well-balanced tooth morphology and health gum profiles (Red-White Esthetics). Largely, there lie some differences in the input system of the 3-dimentional data from the prepared abutments between respective computer-assisted systems available now. But the manufacturing systems (CAM) are very similar between them, to say, comprise numeric control systems with whole 3-dimensional milling units according to the restorations to be made. Now the author is going to present CAD/CAM Zirconia All Ceramic Restoration on the topics for the Red-White Esthetics, periodontal control and maintenance, treatment for the discolored teeth, post & core build-up works for the devitalized teeth, characteristics of the Zirconium oxide All Ceramics, fabrication procedures, clinical considerations and its application to diverse clinical situations.