• The Journal of the Korean dental association
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• v.25 no.6 s.217
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• pp.578-587
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• 1987

The purpose of this was to examine the distribution and the bond failure of the acidetched ceramometal retainer (Maryland Bridge). 126 subjects who treated by faculty and residents of Department of Prosthodontics, Seoul National University Hospital from Dec. 1982 to Dec. 1986 were selected for this study. From the foregoing study author obtained the following conclusions. 1. A total of 135 restorations were placed in the mouths of patients ranging in age from 11 to 70 years (Man 62, woman 64) 2. Most restorations were applied to replace anterior teeth. 3. It was found that of the total number of bridges constructed 59.3 percent were the three-unit type. 4. Replacing one tooth missing was the most frequent cases(74.1 percent). 5. Of the total number of cases, 10.4percent showed bond failure. 6. The bond failure, author suggest, be due to one or more of mis-fit of framework, occlusion, material in itself, faulty case selection and lack of technique.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.11a
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• pp.295-298
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• 1998

We have investigated ionic conductivity and electrochemical stability of the electrolytes containing organic solvent. Ion conductivities were measured between 10 and 80$^{\circ}C$, and electrochemical stabilities were determined by cyclic voltammetry on glassy carbon, platinum and aluminum electrodes. Ionic conductivity of electrolyte(EC:DEC=1:1) with IM LiPF$\_$6/ shows better than that of the other electrolytes having Li salts. The IM LiBF$_4$-PC electrolyte exhibits good electrochemical stability. IM LiPF$\_$6/ (EC:DEC=1:1) and IM LiPF$\_$6/ (EC:DMC=1:1) electrolytes are used for the high capacity of battery system.

• The Journal of Korean Academy of Prosthodontics
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• v.24 no.1
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• pp.7-16
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• 1986

The purpose of this study was to examine the distribution and the bond failure of the acid-etched ceramometal retainer (Maryland Bridge). 126 subjects who treated by faculty and residents of Department of Prosthodontics, Seoul National University Hospital from Dec. 1982 to Dec. 1986 were selected for this study. From the foregoing study author obtained the following conclusions. 1. A total of 135 restorations were placed in the mouths of patients ranging in age from 11 to 10 years (man 62, woman 64). 2. Most restorations were applied to replace anterior teeth. 3. It was found that of the total number of bridges constructed 59.3 percent were the three-unit type. 4. Replacing one tooth mining was the most frequent cases (74.1 percent). 5. Of the total number of cases, 10.4 percent stowed bond failure. 6. The bond failure, author suggest, be due to one or more of mis-fit of framework, occlusion, material in itself, faulty case selection and lack of technique.

• Food Science and Biotechnology
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• v.16 no.2
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• pp.306-310
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• 2007

Setoka (Tangor Norin No.8) is a superior tangor cultivar cultivated in a greenhouse on Jeju Island, and its ${\beta}-cryptoxanthi$n content was determined during the ripening season (September 2005 to March 2006). The ${\beta}-cryptoxanthi$n content of the peel of Setoka fruits was higher than that of the flesh. Also, the ${\beta}-cryptoxanthi$n content in both peel and flesh gradually increased through the ripening season from the beginning of pigmentation, and then decreased slightly late in the ripening season. The ${\beta}-cryptoxanthi$n content in the peel of Setoka fruits varied throughout the season with values of 0.02 (Sep), 0.67 (Nov.), 2.27 (Dec.), 2.88 (Jan.), 2.27 (Feb.), and 2.13 mg% (Mar.). The ${\beta}-cryptoxanthi$n content in Setoka fruit flesh increased throughout the ripening season with values of 0.05 (Sep.), 0.22 (Nov.), 0.57 (Dec.), 0.80 (Jan.), and 0.91 mg% (Feb).

• Journal of the Korean Electrochemical Society
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• v.3 no.4
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• pp.224-231
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• 2000

The exfoliation of graphite (layer) was progressed due to the irreversible insertion of PC molecules between graphene layers, when propylene carbonate (PC) solvent was used as the organic solvents. The problem could be mitigated by the replacement of PC by ethylene carbonate (EC). But, the freezing point of EC-based electrolyte increased due to the high freezing point of $EC(36.2^{\circ}C)$. Therefore, EC+PC mixed electrolyte is expected as a good organic electrolyte for lithium ion battery. The EC-based organic electrolyte containing PC within pertinent quantity can be expected to have high molar conductivity and reduced exfoliation of graphite layer. The dielectric constant and molar conductivity of $LiPF_6/PC+EC+DEC$ electrolyte was investigated with a variation in the PC content. The electrochemical properties of carbon electrode in the electrolyte were also investigated. Molar conductivity and dielectric constant increased linearly by increasing the PC volume fraction in the electrolyte. The results of charge-discharge test for carbon/electrolyte/Li cell indicated that the initial irreversible specific capacity(IIC) of MCMB-6-28s and MPCF3000 decreased by the addition of $0.83 vol\%$ of PC, but increased with PC content over than $0.83 vol\%$. In the case of MPCF3000 and PCG100 having less than $10 vol\%$ PC, IIC was lower than 50 mAh/g. The discharge specific capacities varied with carbon material, but did not vary with PC content in the electrolyte.

• Tunnel and Underground Space
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• v.9 no.2
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• pp.102-113
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• 1999

Two-dimensional and three-dimensional DEM programs, UDEC and 3DEC, were used to investigate the mechanical stability of the conceptual design of deposition drift and deposition holes constructed in a crystalline rock mass. From the simulations, the influence of discontinuities, the number of deposition holes, and deposition hole interval on the stability of deposition drift and deposition holes could be determined. From the two-dimensional and three-dimensional analysis. it was concluded that three-dimensional analysis should be carried 7ut fur deriving reliable conclusions. Even though the deposition hole interval changed from 8 m to 3 m, which did not damage the mechanical stability of the deposition drift.

• Environmental Engineering Research
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• v.10 no.6
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• pp.306-315
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• 2005

Total gas phase mercury (TGM) concentrations and event wet-only precipitation for Hg were collected for nine months (from April, 2002 to Dec., 2002) at Sterling, NY on the shoreline of Lake Ontario. TGM concentrations measured in this study ($3.02{\pm}2.14\;ng/m^3$) were in somewhat high range compared to other background sites. Using simplified quantitative transport bias analysis (SQTBA) possible sources affecting high Hg concentration in Sterling was identified, and they are coal-fired power plants located in southern NY and Pennsylvania. Wet deposition measured at Mercury Deposition Network (MDN) sites including Pt. Petre and Egbert, ON were compared with data obtained at the Sterling to estimate the total mercury wet deposition flux to Lake Ontario. The wet deposition flux was calculated to be the highest at the Sterling site ($7.94\;{\mu}g/m^2$ from April, 2002 to Dec. 2002) and the lowest at the Egbert ($3.92\;{\mu}g/m^2$), due to the both the difference in precipitation depth and Hg concentration in the precipitation. The deposition measured at the Sterling site is similar to Lake Michigan deposition of $6-14\;{\mu}g/m^2$ (converted for ninth months) measured for Lake Michigan Mass Balance Study (LMMBS).

• Journal of Electrical Engineering and information Science
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• v.3 no.2
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• pp.261-266
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• 1998

This paper describes the fabrication and characterization of dual-polysilicon gated surface channel 0.1$\mu\textrm{m}$ CMOSFETs using BF2 and arsenic as channel dopants. We have used and LDD structure and 40${\AA}$ gate oxide as an insulator. To suppress short channel effects down to 0.1$\mu\textrm{m}$ channel length, shallow source/drain extensions implemented by low energy implantation and SSR(Super Steep Retrograde) channel structure were used. The threshold voltages of fabricated CMOSFETs are 0.6V. The maximum transconductance of nMOSFET is 315${\mu}$S/$\mu\textrm{m}$, and that of pMOSFET is 156 ${\mu}$S/$\mu\textrm{m}$. The drain saturation current of 418 ${\mu}$A/$\mu\textrm{m}$, 187${\mu}$A/$\mu\textrm{m}$ are obtained. Subthreshold swing is 85mV/dec and 88mV/dec, respectively. DIBL(Drain Induced Barrier Lowering) is below 100mV. In the device with 2000${\AA}$ thick gate polysilicon, depletion in polysilicon near the gate oxide results in an increase of equivalent gate oxide thickness and degradation of device characteristics. The gate delay time is measured to be 336psec at operation voltage of 2V.

• Carbon letters
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• v.1 no.3_4
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• pp.148-153
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• 2001

The initial irreversible capacity, $Q_i$, is one of the parameters to express the material balancing of the cathode to anode. We introduced new terms, which are the initial intercalation Ah efficiency (IIE) and the initial irreversible specific capacity at the surface ($Q_{is}$), to express precisely the irreversibility of an electrode/electrolyte system. Two terms depended on kinds of active-materials and compositions of the electrode, but did not change with charging state. MPCF had the highest value of IIE and the lowest value of $Q_{is}$ in 1M $LiPE_6$/EC + DEC (1 : 1 volume ratio) electrolyte. IIE value of $LiCoO_2$ electrode was 97-98%, although the preparation condition of the material and the electrolyte were different. $Q_{is}$ value of $LiCoO_2$ was 0~1 mAh/g. MPCF-$LiCoO_2$ cell system had the lowest of the latent capacity. $Q_{is}$ value increased slightly by adding conductive material. IIE and $Q_{is}$ value varied with the electrolyte. By introducing PC to EC+DEC mixed solvent, IIE values were retained, but $Q_{is}$ increased. In case of addition of MP, IIE value increased and $Q_{is}$ value also increased a little.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.2
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• pp.93-98
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• 2020

We investigated the effect of a post-annealing process using ultraviolet (UV) light on the electrical properties of solution-processed InZnO (IZO) thin-film transistors (TFTs). UV light was irradiated on IZO TFTs for different time periods of 0s, 30s, and 90s. We measured transfer and retention stability curves to evaluate the performance of the fabricated TFTs. In addition, we measured height, amplitude, and phase AFM images to analyze changes in the surface and morphology of the devices. AFM measurements were performed by setting the drive amplitude of the cantilever tip to 47.9 mV in tapping mode, then dividing the device surface into 500 nm × 500 nm. In the case of IZO TFT irradiated with UV for 30s, the electron mobility and I_on/I_off ratio were improved, the threshold voltage was reduced by approximately 2 V, and the subthreshold swing also decreased form 1.34 V/dec to 1.11 V/dec.