• Journal of the Korean Ceramic Society
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• v.14 no.1
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• pp.12-18
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• 1977

In our former paper, tremolitic talc, -wollastonite-clay system was studied. In this study blast furnace slag was used(B.F.S.) instead of wollastonite for developing a fast-firing wall tile body. The wall tile bodies consisting of tremolitic talc and B.F.S. asmajor constituents have been fired in the temperature range 1000-120$0^{\circ}C$. Some of these bodies have showed good properties for wall tile manufacture. According to the increased content of B.F.S the fired bodies have showed the decreased thermal expansion which was resulted from the fact that the amounts of diopside and anorthite were gradually increased and those of quartz relatively decreased. Being reasonable in low price and thermo-stable properties tremolitic talc and B.F.S. will be good materials for the fast-firing tile body.

• Speech Sciences
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• v.8 no.3
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• pp.93-104
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• 2001

The author analyzed acoustic parameters of ten Korean numbers produced by ten male students using Praat. Variations of f0, F1, F2 and F3 within and between speakers were examined by determining an average and standard deviation of the parameters of each number and by comparing the acoustic values with one another. Results showed that each subject produced the numbers within a certain range of variation across time. Thus, speaker identification can be more certain using dynamic information of the acoustic parameters within each vocalic segment. Also, percent difference of within-subjects' variation to that of between-subjects can be utilized to determine which sounds would be better stimuli for speaker identification. According to the criteria, the number '2' proved the best stimulus while the number '7' was the worst. Future studies will be necessary to explore robust methods of speaker identification under noisy conditions.

• Journal of muscle and joint health
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• v.23 no.2
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• pp.95-104
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• 2016

Purpose: The purpose of this study was to examine body composition and dietary self-efficacy in nursing students. Methods: The study was a descriptive, correlational study with a convenience sample of 197 female nursing students. This study was conducted from April 1st to May 31th in 2015. SPSS 21.0 program was used for data analysis. Results: The average of body protein was $7.90{\pm}1.17kg$ and normal range was 33%. A BMI's average was $21.02{\pm}2.94kg/m^2$ and 62.9 fell into standard range. The average of dietary self-efficacy of subjects was $3.42{\pm}0.53$. The subjects performed intense physical activities during three or more days had higher body protein (F=5.89, p=.003), body minerals (F=6.15, p=.003) and body-efficacy (F=4.13, p=.017) but remarkably lower body fat (F=4.04, p=.019). There is no noticeable correlation of body composition with dietary self-efficacy. However, it is obvious that each category of body composition had a significant positive correlation. Conclusion: This study demonstrated that students who were inclined to overeat had higher body protein, body minerals, body fat, and BMI. Students performed intense physical activities had high body protein, body minerals, and dietary self-efficacy, whereas they had low body fat. Each entry between the body composition had a significant positive correlation.

• Korean Journal of Food Science and Technology
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• v.23 no.6
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• pp.723-731
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• 1991

In order to optimize sterilization conditions of retort pouched curry sauce, sterilization processes for eighteen conditions by varying temperature, time and method were conducted through $3^{2}{\times}2^{1}$ experimental factorial design. Quality evaluations before and after sterilization included measurements of vitamin (niacin) retention, pH and color differences, and organoleptic test(taste, color and viscosity). $F_{o}$ values were also measured at each condition. Product qualities were mainly affected by sterilization temperature and time, whereas sterilization method had no significant effect. Effect of sterilization time on product qualities was higher than that of sterilization temperature. From the response surface analysis, an optimum range of sterilization condition simultaneously satisfying desired specifications was determined to be $123.5^{\circ}C$, 21.5 min to $127.5^{\circ}C$, 17.0 min. In this range, the sterility($F_{o}$ value) at a cold point during sterilization was approximately 15.0 min.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.3
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• pp.23-32
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• 2004

The local geologic and dynamic site characteristics, which include soil profiles, shear wave velocity profiles and depths to the bed rock were gathered from 148 sites all over the Korean peninsula and those values are compared to those in the western USA. Site response analyses were performed based on equivalent linear scheme using design rock-outcrop acceleration of 0.154g which corresponds to the collapse level of earthquake for seismic category I structure. The results show that the amplification factor based on Korean seismic design guideline underestimates the motion in short-period range and overestimates the motion in mid-period range. It is suggested that the existing Korean seismic guideline based on UBC is required to be modified considering dynamic site characteristics in Korea for the reliable estimation of site amplification.

• 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.

• Journal of the Korean Applied Science and Technology
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• v.38 no.2
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• pp.378-388
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• 2021

This study investigated the effect of Ego-resilience, Marital communication, and Mental health on Happiness among middle-aged women Methods: A descriptive correlation study design was used with a convenience sample consisting of 239 women. SPSS Win21.0 program was used for the descriptive analysis, t-test, ANOVA, Pearson's correlation coefficient analysis, and multiple-regression analysis. The mean score for ego-resilience was 3.46±.527(range: 1-5), marital communication was 2.44±.52(range: 1-5), mental health 1.82±.66(range: 0-4) and happiness was 3.21±56(ranse: 1-5). Happiness was found to have a significant positive correlation with ego-resilience(r=.393, p<.001) and negative correlation with somatization(r=-.134 p=.039), depression(r=-.356, p<.001), anxiety(r=-.269, p<.001). The predictive factors on the Happiness were depression(β=-.437, p<.001), ego-resilience(β=.350, p<.001), Somatization(β=.239, p=.009) and subjective health status: average (β=-.150, p=.009), unhealthy(β=-.147, p=.015). The explanatory power was 30.4% (F=14.02, p <.001). Based on the findings of this study, it is important to provide services to ego-resilience and mental health among middle aged women.

• Korean Journal of Materials Research
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• v.22 no.5
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• pp.215-219
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• 2012

Red phosphors $Ca_{1-1.5x}WO_4:{Eu_x}^{3+}$ were synthesized with different concentrations of $Eu^{3+}$ ions by using a solid-state reaction method. The crystal structure of the red phosphors was found to be a tetragonal system. X-ray diffraction (XRD) results showed the (112) main diffraction peak centered at $2{\theta}=28.71^{\circ}$, and the size of crystalline particles exhibited an overall decreasing tendency according to the concentration of $Eu^{3+}$ ions. The excitation spectra of all the phosphors were composed of a broad band centered at 275 nm in the range of 230-310 nm due to $O^{2-}{\rightarrow}W^{6+}$ and a narrow band having a peak at 307 nm caused by $O^{2-}{\rightarrow}Eu^{3+}$. Also, the excitation spectrum presents several strong lines in the range of 305-420 nm, which are assigned to the 4f-4f transitions of the $Eu^{3+}$ ion. In the case of the emission spectrum, all the phosphor powders, irrespective of $Eu^{3+}$ ion concentration, indicated an orange emission peak at 594 nm and a strong red emission spectrum centered at 615 nm, with two weak lines at 648 and 700 nm. The highest red emission intensity occurred at x = 0.10 mol of Eu3+ ion concentration with an asymmetry ratio of 12.5. Especially, the presence of $Eu^{3+}$ in the $Ca_{1-1.5x}WO_4:{Eu_x}^{3+}$ shows very effective use of excitation energy in the range of 305-420 nm, and finally yields a strong emission of red light.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.179-188
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• 2006

In this study, R/S analysis which was proposed by Mandelbrot & Wallis(1969) was applied to evaluate the presence of the fractal property in the cone tip resistance of in-situ CPT data. Hurst exponents(H) were evaluated in the range of $0.660\sim0.990$ and the average was 0.875. It was confirmed that a cone tip resistance data had the characteristic of fractals and it was expected that cone tip resistance data sets are well approximated by a fBm process with an Hurst exponent near 0.875. It was also observed that the boundary between layers were obviously identified as a result of R/S analysis and it will be usage in practices.

• Bulletin of the Korean Chemical Society
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• v.29 no.2
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• pp.398-404
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• 2008

A new solvent polymeric membrane electrode, based on N,N'-bis(salicylidene)-2,2-dimethylpropane-1,3-diamine Ni(II) as the ionophore, was designed. The oxalate-selective electrode has the dynamic range between 1.0 10-6 M and 1.0 10-1 M with a Nernstian slope of -28.7 1.0 mV per decade. The detection limit was 6.3 10-7 M. The proposed electrode revealed good selectivities for oxalate over a variety of other anions and could be used in a pH range of 2.0-7.8. The electrode can be used for at least two months without any considerable divergence in potential. The designed electrode was applied as an indicator electrode in the potentiometric determination of oxalate in real samples.