• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1996.11a
• /
• pp.71-74
• /
• 1996

Ta$_2$O$_{5}$ film ale recognized as promising capacitor dielectric for future DRAM\`s. The electrical properties of Ta$_2$O$_{5}$films greatly depend on the heating condition. In the practical fabrication process, several annealing process, such as the annealing of Al in H$_2$(about 40$0^{\circ}C$) and reflow of BPSG (borophosphosilicate glass) film in $N_2$(about 80$0^{\circ}C$), exist after deposition of Ta$_2$O$_{5}$ film. In this paper, we describe the temperature effect on the electrical properties of W/Ta$_2$O$_{5}$/Si structure. The thin film of Ta$_2$O$_{5}$ and tungsten have been deposited on p-si(100) wafer using the sputtering system. The heating temperature was varied from 500 to 90$0^{\circ}C$ in $N_2$for 30min and The degree of temperature is 100\`C. In a log(J/E$^2$) Vs 1/E plot of typical I-V data, we find a linear relationship for the temperature of 500, $600^{\circ}C$ and as deposition. This could indicate Fowler-Nordheim tunneling as the dominant mode of current transports. However, we can not find a linear relationship for the temperature above $700^{\circ}C$. This could not indicate Fowler-Nordheim tunneling as the dominant mode of current transport. The high frequency (1MHz) capacitance-voltage (C-V) of W/Ta$_2$O$_{5}$/Si Capacitor were investigated on the basis of shift in the threshold voltage and dielectric constant. The magnitude of the threshold voltage and dielectric constant depends on the heating temperature, and increases with heating temperature.temperature.

• The Journal of Korean Medicine
• /
• v.36 no.2
• /
• pp.8-20
• /
• 2015

Objectives: This study aims to evaluate the efficacy of pharmacopuncture in the treatment of acute peripheral facial paralysis (APFP) through a meta-analysis of randomized controlled trials to assess the clinical evidence for pharmacopuncture as a treatment for PFP. Methods: Literature was searched using databases. The search terms used were "pharmacopuncture," "sweet BV," "apipuncture," "apitoxin," "injection acupuncture," and "herbal acupuncture" in English and "bongchim," "bongyakchim," and "yakchim" in Korean. The RevMan 5.2 program was used for meta-analysis. Results: In all, 1902 studies were screened and the full texts of 219 articles were reviewed. Of these, nine studies were included in the systematic review and nine studies were included in the meta-analysis. Treatments utilizing bee venom, sweet bee venom (SBV), Soyeom, Calculus Bovis Fel Ursi Moschus (BUM), Hominis Placenta, and Suseunghwagang (SSHG) were observed in nine RCTs. In the forest plot, the diamond favors the PA treatment against the control treatment. (95% CI: 0.34 [0.08, 0.60], Z = 2.57, P = 0.01), which Our meta-analysis in RevMan 5.2 confirmed the significant efficacy of PA in treating APFP. Conclusion: Our systematic review and meta-analysis suggest that treatments using Soyeom, bee venom, and BUM are effective in APFP and they reduce the duration of postauricular pain occurring at the acute stage of APFP. However, due to small effect size, further investigation is needed.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.10 no.2
• /
• pp.82-91
• /
• 2002

The study was executed to evaluate the agricultural utilization of phyllite as composting bulking agent in pig manure. The effects of the composted pig manure were verified by adopting the mixture of 10% phyllite and 20% saw dust(PSPC 10) and 20% phyllite and 10% saw dust(PSPC 20). The pig manure mixed with 30% saw dust was used as a control(PSC). However C/N ratio was very decreased because humus was rapidly progressed at PSPC 20 plot during the composting. Also, $NH_4{^+}-N$, $NO_3{^-}-N$, pH and EC were quickly changed from after one week and CEC was the highest as $92cmol_c/kg$. And Total-N was hardly changed during the composting but total carbon was rapidly declined as processing compost. Therefore, the phyllite has positively showed comparing with others in the street as compost bulking agent and go ahead, it is concerned that this material should have to research and investigating, constantly.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.57 no.1
• /
• pp.25-35
• /
• 2015

As livestock manure treatment is becoming a problem, manure application in forest plantation is recommended as an alternative. In this study, to investigate the impact due to liquid manure application in forest plantation, soil, soil water and shallow groundwater quality had been monitored in poplar experimental site where the liquid manure (LM) was applied. Water samples were collected weekly during growing season (April to October) from 2008 to 2011. From the monitoring results, phosphorus concentration in the soil and soil water had no significant difference between LM and control plots. $NO_3$-N concentration of soil water in LM, however, showed higher concentration (13.6 mg/l at 40 cm, 35.1 mg/l at 80 cm) than control plot (1.5 mg/l at 40 cm, 0.5 mg/l at 80 cm). In case of shallow groundwater quality, pH, heavy metal, etc. were satisfied to the national agricultural water quality standard of groundwater and there were no significant difference between upstream and downstream. The $NO_3$-N concentration of shallow groundwater was also not exceeded the national drinking water standard. However, $NO_3$-N concentration in soil water and downstream of shallow groundwater had increased in 2011 when non-composted LM was applied mostly in non-growing season of tree (September). From the results, it is important to control nitrogen source, application time and decomposed or not when LM is applied. In addition, to investigate nitrate source, further long-term monitoring and modelling could be necessary.

• Journal of Korean Society of Forest Science
• /
• v.79 no.3
• /
• pp.260-268
• /
• 1990

Two types of ridge regression estimators were compared with the ordinary least squares (OLS) estimator in order to select the "best" estimator when multicollinearitc existed. The ridge estimators were Mallows's (1973) $C_P$-like statistic, and Allen's (1974) PRESS-like statistic. The evaluation was conducted based on the predictive ability of a yield model developed by Matney et al. (1988). A total of 522 plots from the data of the Southwide Loblolly Pine Seed Source study was used in this study. All of ridge estimators were better in predictive ability than the OLS estimator. The ridge estimator obtained by using Mallows's statistic performed the best. Thus, ridge estimators can be recommended as an alternative estimator when multicollinearity exists among independent variables.

• Bulletin of the Korean Chemical Society
• /
• v.23 no.8
• /
• pp.1089-1096
• /
• 2002

Solvolyses rate constants of trimethylacetyl chloride (2), isobutyryl chloride (3), diphenylacetyl chloride (4) and p-methoxyphenylacetyl chloride (5) in 2,2,2-trifluoroethanol (TFE)-water, 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP)-water and TFE-et hanol solvent systems at $10^{\circ}C$ are determined by a conductimetric method. Kinetic solvent isotope effects (KSIE) are reported from additional kinetic data for methanolyses of various substituted acetylchlorides in methanol According to the results of those reactions analyzed in terms of rate-rate profiles,extended Grunwald-Winstein type correlations, application of a third order reaction model based a general base catalyzed (GBC) and KSIE values. Regardless of the kind of neighboring groups (CH3- or Ph-groups) of reaction center, for aqueous fluorinated alcohol systems, solvolyses of 2, 3, 4, and 5 were exposed to the reaction with the same mechanism (a loose SN2 type mechanism by electrophilic solvation) controlled by a similarity of solvation of the transition sate (TS). Whereas, for TFE-ethanol solvent systems, the reactivity depended on whether substituted acetyl chloride have aromatic rings (Ph-) or alkyl groups (CH3-); the solvations by the predominant stoichiometric effect (third order reaction mechanism by GBC and/or by push-pull type) for Ph- groups (4 and 5) and the same solvation effects as those shown in TFE-water solvent systems for CH3- groups (2 and 3) were exhibited Such phenomena can be interpreted as having relevance to the inductive effect ( $\sigmaI)$ of substituted groups; the plot of log (KSIE) vs. ${\sigma}I$ parameter give an acceptable the linear correlation with r = 0.970 (slope = 0.44 $\pm$ 0.06, n = 5).

• Bulletin of the Korean Chemical Society
• /
• v.26 no.7
• /
• pp.1065-1070
• /
• 2005

$[Mn_{12}O_{12}(O_2CPh-4-SMe)_{16}(H_2O)_4]{\cdot}7CH_2Cl_2$ (1), a new single-molecule magnet complex has been successfully synthesized by substitution of acetate ligand of Mn12ac with 4-(methylthio)benzoic acid. Complex 1 crystallizes into triclinic P$\overline{1}$ with a = 18.321(3) $\AA$, b = 19.011(3) $\AA$, c = 27.230(4) $\AA$, $\alpha$ = 86.973(3)$^{\circ}$, $\beta$ = 76.919(3)$^{\circ}$, $\gamma$ = 87.613(3)$^{\circ}$, and Z = 2. In complex 1, one Mn(III) ion has an abnormal Jahn-Teller elongation axis oriented at an oxide ion. Complex 1 has two out-of-phase ac susceptibility peaks in the 2-4 K and 4-7 K regions. Effective anisotropy energy barrier and pre-exponential factor are $U_{eff}$ = 45.95 K, 1/$\tau$0 = 8.6 ${\times}\;10^9s^{-1}\;for\;{\chi}_M$'' peaks in the lower temperature region and $U_{eff}$ = 59.45 K, 1/$\tau_0$ = 2.2 ${\times}\;10^8\;s^{-1}$ for $\chi_M$'' peaks in the higher temperature region. The parameters of S = 10, g = 1.87, D = -0.40 $cm^{-1}$, and E = 0.00034 $cm^{-1}$ were obtained from the M/N${\mu}_B$ vs. H/T plot of complex 1.

• Imaging Science in Dentistry
• /
• v.40 no.4
• /
• pp.179-185
• /
• 2010

Purpose : Cortical bone thickness is one of the important factor in mini-implant stability. This study was performed to investigate the buccal cortical bone thickness at every interdental area as an aid in planning mini-implant placement. Materials and Methods : Two-dimensional slices at every interdental area were selected from the cone-beam computed tomography scans of 20 patients in third decade. Buccal cortical bone thickness was measured at 2, 4, and 6 mm levels from the alveolar crest in the interdental bones of posterior regions of both jaws using the plot profile function of $Ez3D2009^{TM}$ (Vatech, Yongin, Korea). The results were analyzed using by Mann-Whitney test. Results : Buccal cortical bone was thicker in the mandible than in the maxilla. The thickness increased with further distance from the alveolar crest in the maxilla and with coming from the posterior to anterior region in the mandible (p<0.01). The maximum CT value showed an increasing tendency with further distance from the alveolar crest and with coming from posterior to anterior region in both jaws. Conclusion : Interdental buccal cortical bone thickness varied in both jaws, however our study showed a distinct tendency. We expect that these results could be helpful for the selection and preparation of mini-implant sites.

• Corrosion Science and Technology
• /
• v.2 no.2
• /
• pp.68-74
• /
• 2003

The effects of Niobium on the structure and properties(especially electric properties) of passive film of Zirconium alloys in pH 8.5 buffer solution are examined by the photo-electrochemical analysis. For Zr-xNb alloys (x = 0, 0.45, 1.5, 2.5 wt%), photocurrent began to increase at the incident energy of 3.5 ~ 3.7 eV and exhibited the $1^{st}$ peak at 4.3 eV and the $2^{nd}$ peak at 5.7 eV. From $(i_{ph}hv)^{1/2}$ vs. hv plot, indirect band gap energies $E_g{^1}$= 3.01~3.47 eV, $E_g{^2}$= 4.44~4.91 eV were obtained. With increasing Nb content, the relative photocurrent intensity of $1^{st}$ peak significantly increased. Compared with photocurrent spectrum of thermal oxide of Zr-2.5Nb, It was revealed that $1^{st}$ peak in photocurrent spectrum for the passive film formed on Zr-Nb alloy was generated by two types of electron transitions; the one caused by hydrous $ZrO_2$ and the other created by Nb. Two electron transition sources were overlapped over the same range of incident photon energy. In the photocurrent spectrum for passive film formed on Zr-2.5Nb alloy in which Nb is dissolved into matrix by quenching, the relative photocurrent intensity of $1^{st}$ peak increased, which implies that dissolved Nb act as another electron transition source.

• Journal of the Korean Dietetic Association
• /
• v.22 no.3
• /
• pp.214-224
• /
• 2016

The purpose of this study was to assess the physical activity of preschool children using an accelerometer and investigate differences related to epoch length setting during use of the accelerometer. Subjects of the study were 26 children (12 boys and 14 girls) at the age of 5, enrolled in one preschool located in Gangneung. From 9:00 a.m. to 4:00 p.m. (7 hours period), every child wore a total of four accelerometers (ActiGraph $GT3X^+$, USA), including three attached to the left hip (with epoch length set at 5 seconds, 15 seconds, and 30 seconds). For comparison purposes, a forth was attached to the opposite position, with epoch length set at 5 seconds. Data collected using 15s epoch and 30s epoch (single larger epoch) were compared with those obtained after reintegration of 5s to 15s epoch, 5s to 30s epoch, and 15s to 30s epoch, respectively (smaller epochs reintegrated). According to the results of this study, there were no significant differences in VM between 30s epoch and 5s to 30s epoch reintegrated and in MVPA (moderate-to-vigorous physical activity), between 15s epoch and 5s to 15s epoch reintegrated. From the Bland-Altman plot, reintegration of 15s to 30s epoch in VM and reintegrations of 15s to 30s epoch and 5s to 15s epoch in MVPA can be recommended for assessing physical activity in preschool children. Further research is needed into the reintegration method while using an accelerometer for assessment of energy expenditure in children.