• Journal of the Korean Mathematical Society
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• v.54 no.2
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• pp.697-711
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• 2017

Let X, Y be real normed vector spaces. We exhibit all the solutions $f:X{\rightarrow}Y$ of the functional equation f(rx + sy) + rsf(x - y) = rf(x) + sf(y) for all $x,y{\in}X$, where r, s are nonzero real numbers satisfying r + s = 1. In particular, if Y is a Banach space, we investigate the Hyers-Ulam stability problem of the equation. We also investigate the Hyers-Ulam stability problem on a restricted domain of the following form ${\Omega}{\cap}\{(x,y){\in}X^2:{\parallel}x{\parallel}+{\parallel}y{\parallel}{\geq}d\}$, where ${\Omega}$ is a rotation of $H{\times}H{\subset}X^2$ and $H^c$ is of the first category. As a consequence, we obtain a measure zero Hyers-Ulam stability of the above equation when $f:\mathbb{R}{\rightarrow}Y$.

• Communications of the Korean Mathematical Society
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• v.22 no.1
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• pp.65-74
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• 2007

Suppose that $\mu$ is a finite positive Borel measure on bounded symmetric domain $\Omega{\subset}\mathbb{C}^n\;and\;\nu$ is the Euclidean volume measure such that $\nu(\Omega)=1$. Suppose 1 < p < $\infty$ and r > 0. In this paper, we will show that the norms $sup\{\int_\Omega{\mid}k_z(w)\mid^2d\mu(w)\;:\;z\in\Omega\}$, $sup\{\int_\Omega{\mid}h(w)\mid^pd\mu(w)/\int_\Omega{\mid}h(w)^pd\nu(w)\;:\;h{\in}L_a^p(\Omega,d\nu),\;h\neq0\}$ and $$sup\{\frac{\mu(E(z,r))}{\nu(E(z,r))}\;:\;z\in\Omega\}$$ are are all equivalent. We will also show that the inclusion mapping $ip\;:\;L_a^p(\Omega,d\nu){\rightarrow}L^p(\Omega,d\mu)$ is compact if and only if lim $w\rightarrow\partial\Omega\frac{\mu(E(w,r))}{\nu(E(w,r))}=0$.

• Phonetics and Speech Sciences
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• v.4 no.4
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• pp.71-77
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• 2012

Sasang constitution experts utilize voice characteristics as an auxiliary measure for deciding a person's constitutional group. This study aims at establishing a relationship between speech features and the constitutional groups by subjective listening evaluation of voice characteristics. A speech database of 841 speakers whose constitutional groups have been already diagnosed by Sasang constitution experts was constructed. Speech features related to speech source and vocal tract filter were extracted from five vowels and one sentence. Statistically significant speech features for classifying the groups were analyzed using SPSS. The features contributed to constitution classification were speaking rate, Energy, A1, A2, A3, H1, H2, H4, CPP for males in their 20s, F0_mean, CPP, SPI, HNR, Shimmer, Energy, A1, A2, A3, H1, H2, H4 for females in their 20s, Energy, A1, A2, A3, H1, H2, H4, CPP for male in the 60s, and Jitter, HNR, CPP, SPI for females in their 60s. Experimental results show that speech technology is useful in classifying constitutional groups.

• Journal of applied mathematics & informatics
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• v.13 no.1_2
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• pp.365-372
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• 2003

We show that if ${\gamma}$ $\leq$ 2, the average error of the composite Trapezoidal rule on two consecutive intervals is proportional to h$\^$2h+3/ where h is the length of each subinterval of the interval [0, 1]. As a result, we show that the Trapezoidal rule with equally spaced points is optimal in the average case setting when ${\gamma}$ $\leq$ 2.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.810-816
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• 1996

This study was conducted to measure the hydration characteristics at $20^{\circ}C$ and investigated the effect of water to rice ratio(v/w) on the texture properties of cooked rice of ten different varieties based on maturity. Water absorptions during soaking were completed between 30min and 35min at $20^{\circ}C$. The ranges of equilibrium moisture content were between 0.3247g $H_2O/g$ dry matter and 0.3577g H201g dry matter. During the cooking process, the water content of cooked rice increased 6~7% with increased the ratio of water to rice from 1.4 to 1.6(v/w). The hardness(H) of cooked rice decreased, while the stickiness(-H) and -H/H ratio increased with increased ratio of water to rice.

• Journal of IKEEE
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• v.18 no.4
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• pp.447-455
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• 2014

In this research, n-based 4H-MOS Capacitor was fabricated with PECVD (plasma enhanced chemical vapor deposition) process for improving SiC/$SiO_2$ interface properties known as main problem of 4H-SiC MOSFET. To overcome the problems of dry oxidation process such as lower growth rate, high interface trap density and low critical electric field of $SiO_2$, PECVD and NO annealing processes are used to MOS Capacitor fabrication. After fabrication, MOS Capacitor's interface properties were measured and evaluated by hi-lo C-V measure, I-V measure and SIMS. As a result of comparing the interface properties with the dry oxidation case, improved interface and oxide properties such as 20% reduced flatband voltage shift, 25% reduced effective oxide charge density, increased oxide breakdown field of 8MV/cm and best effective barrier height of 1.57eV, 69.05% reduced interface trap density in the range of 0.375~0.495eV under the conduction band are observed.

• Journal of Preventive Medicine and Public Health
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• v.18 no.1
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• pp.51-57
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• 1985

To attempt to measure the effect of domestic product P.H.A. kit 'Hepa-S' after completion of 'Hepa-Vax' vaccination schedule, P.H.A. test and R.I.A. test on the 330 healthy adults were carried out. The results obtained were as follow ; 1. The positive anti HBs rate after completion of 'Hepa-Vax' vaccination were; in P.H.A. test with domestic product P.H.A. kit 81.2%, in P.H.A. test with foreign product P.H.A. kit 82.7%, and in R.I.A. test 95.8% 2. Using the result of R.I.A. test as the standard, sensitivity of P.H.A. test with domestic product P.H.A. kit was 84.8% and specificity was 100.0% 3. Using the result of R.I.A. test as standard, sensitivity of P.H.A. test with foreign P.H.A. kit was 86.4% and specificity was 100.0%. 4. The concordance rate of P.H.A. test with domestic product and foreign product kit was 98.5%. On the result of this study, there was no significant difference in the validity between the domestic product P.H.A. kit 'Hepa-S' and the foreign P.H.A. kit $'Hebsgencell^{TM}'$. So that it is recommendable to use domestic product P.H.A. kit instead of foreign product P.H.A. kit.

• Journal of the Korean Chemical Society
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• v.9 no.4
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• pp.153-160
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• 1965

Ultraviolet spectrophotometric investigations have been carried out on the systems of benzene with iodine, bromine, chlorine and iodine monobromide in carbon tetrachloride. The results reveal the formation of one to one molecular complexes of the type, $C_6H_6{\cdot}X_2\;or\;C_6H_6{\cdot}IX$ (X denotes halogen atoms). The equilibrium constants obtained at $25^{\circ}$for the complex formation are 0.173, 0.137, 0.0643 and 0.341 $lmole^{-1}$ for $C_6H_6{\cdot}I_2,\;C_6H_6{\cdot}Br_2,\;C_6H_6{\cdot}Cl_2\;and\;C_6H_6{\cdot}IBr$, respectively. These results combined with those obtained by other workers indicate that the relative stabilities of the benzene complexes decrease in the order, $ICl > IBr > I_2 > Br_2 > Cl_2.$ This order may be measure of their relative acidities toward benzene, which is explained in terms of the relative polarizabilities of halogen molecules and the relative electronegativities of halogen atoms.

• Journal of the Korean Mathematical Society
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• v.33 no.3
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• pp.541-555
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• 1996

The Fourier transform plays a central role in the theory of distribution on Euclidean spaces. Although Lebesgue measure does not exist in infinite dimensional spaces, the Fourier transform can be introduced in the space $(S)^*$ of generalized white noise functionals. This has been done in the series of paper by H.-H. Kuo [1, 2, 3], [4] and [5]. The Fourier transform $F$ has many properties similar to the finite dimensional case; e.g., the Fourier transform carries coordinate differentiation into multiplication and vice versa. It plays an essential role in the theory of differential equations in infinite dimensional spaces.

• Structural Engineering and Mechanics
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• v.56 no.4
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• pp.507-534
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• 2015

The present work investigates the behavior of the embankment models resting on soft soil reinforced with ordinary and stone columns encased with geogrid. Model tests were performed with different spacing distances between stone columns and two lengths to diameter ratios (L/d) of the stone columns, in addition to different embankment heights. A total number of 42 model tests were carried out on a soil with undrianed shear strength $${\sim_\sim}10kPa$$. The models consist of stone columns embankment at s/d equal to 2.5, 3 and 4 with L/d ratio equal 5 and 8. Three embankment heights; 200 mm, 250 mm and 300 mm were tested for both tests of ordinary (OSC) and geogrid encased stone columns (ESC). Three earth pressure cells were used to measure directly the vertical effective stress on column at the top of the middle stone column under the center line of embankment and on the edge stone column for all models while the third cell was placed at the base of embankment between two columns to measure the vertical effective stress in soft soil directly. The performance of stone columns embankments relies upon the ability of the granular embankment material to arch over the 'gaps' between the stone columns spacing. The results showed that the ratio of the embankment height to the clear spacing between columns (h/s-d) is a key parameter. It is found that (h/s-d)<1.2 and 1.4 for OSC and ESC, respectively; (h is the embankment height, s is the spacing between columns and d is the diameter of stone columns), no effect of arching is pronounced, the settlement at the surface of the embankment is very large, and the stress acting on the subsoil is virtually unmodified from the nominal overburden stress. When $(h/s-d){\geq}2.2$ for OSC and ESC respectively, full arching will occur and minimum stress on subsoil between stone columns will act, so the range of critical embankment height will be 1.2 (h/sd) to 2.2 (h/s-d) for both OSC and ESC models.