• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.2
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• pp.242-247
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• 1987

Electrophysical phenomena at the silicon semiconductor-electrolyte solution interfaces were analyzed based on the zeta potential of the electrical double layer and microelectrophoresis. The suspensions were composed of the p or n-type silicon particles suspended in the KCI or pH buffer solutions. The approximate diameter of the prepared and sampled sioicon semiconductor pardticles was 1.5\ulcorner. The sign of the zeta poetntials of the p and n-type silicon particles in the KCl and pH buffer solution was positive. A range of electrophoretic mobilities of the p and n-type silicons in the KCl solutions was 5.5-8.9x10**-4 cm\ulcornerV-sec and 4.2-7.9x10**-4cm\ulcornerV-sec, respectively. The range of zeta potentials corresponding to the electrophoretic mobilities is 70.4-114.0mV nad 53.9-101.2mV, respectively. On the other hand, a range of electrophoretic mobilities of the p and n-type silicons in the pH buffer solutions was 1.1x10**-4-2.2x10**-3cm\ulcornerV-sec and 0-2.1x10**-3cm\ulcornerV-sec, respectively. The range of zeta potentials corresponding to the electrophoretic mobilities is 14.1-281.6mV and 0-268.8mV, respectively. The zeta potentials and electrical double layers of the doped silicon semiconductors are decisively influenced by the positively charged ions in the solutions. The maximum values of the zeta potentials in the KCl solutions appeared at a concentration of about 10-\ulcorner. The isoelectric point of the n-type silicon semiconductors appeared at about a pH 7. The effect of the space charge of the doped silicon semiconductors can be neglected compare with the effect of the surface charge.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.11
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• pp.1536-1541
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• 2000

The present study was carried out to measure changes of feed intake and thirst level caused by water deprivation in goats fed on dry feed and to elucidate the relationship between those two parameters. Water deprivation significantly (p<0.01) decreased cumulative feed intake and rate of eating at 30, 60, 90 and 120 min, respectively, after feed presentation. Cumulative feed intake, after completion of 2 h feeding, was reduced by about 20, 21 and 64 % due to water deprivation during feeding for 2 h (WD2), for 22 h (WD22) and for 46 h (WD46), respectively, compared to free access to water (FAW). Compared to the FAW, WD2, WD22 and WD46 increased thirst level by about 5, 5 and 9 times, respectively. Mean thirst level (X, g/30 min) was negatively correlated with cumulative feed intake (Y, g DM) after completion of 2h feeding (Y=1302-0.2 X, $r^2=0.97$, p<0.05). Water deprivation depressed plasma volume and there was a significant positive regression between plasma volume (X, ml) and cumulative feed intake (Y, g DM) after completion of 2h feeding (Y=-1003+0.6 X, $r^2=0.99$, p<0.01). Mean plasma osmolality (X, mOsmol/l) correlated significantly and negatively with cumulative feed intake (Y, g DM) after completion of 2h feeding (Y=27004-84.9 X, $r^2=0.95$, p<0.05). In conclusion, a decrease of feed intake during water deprivation is mainly due to an increase of thirst level quantitatively, and the act of feeding itself induces thirst more than the length of water-deprivation periods in goats fed on dry feeds. The present findings suggest that plasma osmolality and plasma volume which affect thirst level are involved in the decrease of feed intake in water-deprived goats.

• The Korean Journal of Ceramics
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• v.2 no.1
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• pp.25-32
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• 1996

Solid electroyte nasion was synthesized by the optimized solid state reaction minimizing the volume fraction of secondary $ZrO_2$ and glassy phases. To compensate for the evaporation of Na and P during heat-treatment, excess Na and P were added to the starting composition $Na_{1+x} Zr_2 Si_x P_{d-x} O_{12}$ (x=2.1). Phases pure nasicon comparable in volume fraction to the one obtaied from sol-gel process were synthesized after the reaction at $1100~1150^{\circ}C$,$ P_{O2}>=0.1-0.15 $$ZrO_2$ increased with the heat-treatment time due to the decomposition of nasicon phase and that of glassy phase increased as partial oxygen pressure decreased. The synthesized nasion showed a good electrical conductivity of $-1{\times}10^{-2}({\omega}{\cdot}cm)^{-1}$ at $350^{\circ}C$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.04b
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• pp.51-55
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• 2004

$CdS_{0.69}Se_{0.31}$ single crystal grown by sublimation method. Hall effect measurement were carried out by the Van der Pauw method. The measurement values under the temperature were found to be carrier density $n=1.95{\times}10^{23}m^{-3}$, Hall coeffcient $RH=3.21{\times}10^{-5}m^3/c$, conductivity ${\sigma}=362.41{\Omega}^{-1}m^{-1}$, and Hall mobility ${\mu}=1.16{\times}10^{-2}m^2/v.s.$ Heterojunction solar cells of $n-CdS_{0.69}Se_{0.31}/p-Cu_{2-x}S_{0.69}Se_{0.31}$ were fabricated by the substitution reaction. The open-circuit voltage, short-circuit currint density, fill factor and power conversion efficiency of $n-CdS_{0.69}Se_{0.31}/p-Cu_{2-x}S_{0.69}Se_{0.31}$ heterojunction solar cell under $80mW/cm^2$ illumination were found to be 0.41V, $19.5mA/cm^2$, 0.75 and 9.99%, respectivity.

• Journal of the Korean Mathematical Society
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• v.56 no.5
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• pp.1355-1370
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• 2019

A curve $X{\subset}\mathbb{P}^r$ has maximal rank if for each $t{\in}\mathbb{N}$ the restriction map $H^0(\mathcal{O}_{\mathbb{P}r}(t)){\rightarrow}H^0(\mathcal{O}_X(t))$ is either injective or surjective. We show that for all integers $d{\geq}r+1$ there are maximal rank, but not arithmetically Cohen-Macaulay, smooth curves $X{\subset}\mathbb{P}^r$ with degree d and genus roughly $d^2/2r$, contrary to the case r = 3, where it was proved that their genus growths at most like $d^{3/2}$ (A. Dolcetti). Nevertheless there is a sector of large genera g, roughly between $d^2/(2r+2)$ and $d^2/2r$, where we prove the existence of smooth curves (even aCM ones) with degree d and genus g, but the only integral and non-degenerate maximal rank curves with degree d and arithmetic genus g are the aCM ones. For some (d, g, r) with high g we prove the existence of reducible non-degenerate maximal rank and non aCM curves $X{\subset}\mathbb{P}^r$ with degree d and arithmetic genus g, while (d, g, r) is not realized by non-degenerate maximal rank and non aCM integral curves.

• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.730-736
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• 1998

To elucidate whether or not innervation of purinergic nerve and functional action of $P_{2X}$-, $P_{2Y}$-purinoceptor, the neurogenic effects of perivascular nerve stimulation were investigated using by physiograph recording system in isolated coronary artery of pig. 1. The contractile responses induced by perivascular nerve stimulation (20V, 0.5msec, 20sec) were the frequency (2~64Hz) dependent manner. 2. The neurogenic contractile responses induced by perivascular nerve stimulation were inhibited by the pretreatment with either ATP or adenosine ($10^{-7}{\sim}10^{-4}M$). 3. The neurogenic contractile responses induced by perivascular nerve stimulation (20V, 16Hz, 0.5msec, 20sec) were increased by the pretreatment with reactive blue 2, but were not affected by the pretreatment with 8-phenyltheopylline ($10^{-5}M$). 4. The neurogenic contractile responses induced by perivascular nerve stimulation (20V, 16Hz, 0.5msec, 20sec) were inhibited by the desensitization of the P2X-purinoceptor using by treatment of $10^{-5}M$, -methylene ATP as 3 times over again. The accomplished present study on isolated coronary artery of pig suggest that purinergic nerve is innervated and that the neurogenic contractile response was mediated by activation of $P_{2X}$-purinoceptor and the neurogenic relaxative response was mediated by activation of both $P_1$ and $P_{2Y}$-purinoceptor.

• Journal of the Korean Mathematical Society
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• v.43 no.4
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• pp.691-701
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• 2006

In this paper, we construct a new exotic smooth 4-manifold X which is homeomorphic, but not diffeomorphic, to ${\mathbb{C}}\mathbb{P}^2{\sharp}13\overline{\mathbb{C}\mathbb{P}}^2$. Moreover the manifold X has vanishing Seiberg-Witten invariants for all $Spin^c$-structures of X and has no symplectic structure.

• Honam Mathematical Journal
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• v.40 no.1
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• pp.139-153
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• 2018

Let $P{\geq}3$ be an integer and let ($U_n$) denote generalized Fibonacci sequence defined by $U_0=0$, $U_1=1$ and $U_{n+1}=PU_n-U_{n-1}$ for $n{\geq}1$. In this study, when P is odd, we solve the equation $U_n=11x^2+1$. We show that only $U_1$ and $U_2$ may be of the form $11x^2+1$.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.3 no.1
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• pp.37-49
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• 1996

The Purposes of this study were to understand the types of appellations used by nurses and doctors for patients in a hospital and to analyze satisfaction and reason about appellation for patient. This would enable us to provide basic data on culturally suitable appellations for admitted patients. 454 patients at K University hospital in Seoul were subjects for this study. Subjects were interviewed individually using a questionnair and frequency $X^2-test$. Results are as follows. 1. The most frequently used type of appellations in hospitals was '-ssi ; -sir' used by 88.1% of the nurses and 83.9% of the doctors. About 3 quaters of the medical staff used '-ssi' while none used job position. 2. 93.2% of the patients were satisfied with the appellations used by nurses and 93.0% of the patients were satisfied with the appellations used by the doctors 43.7% didn't think appellations were important and 44.3% thought it natural to use the appellation. The most satisfactory form of appellation used by nurses was '-ssi' to 93.3% of patients. All were satisfied with '-nim ; -sir', '-teacher' and there was no statistically significance. On the other hand, the level of satisfaction and the appellation used by doctors showed a relationship($X^2=19.72$, p=.000). Every patient was satisfied with '-nim' and '-teacher' but 19.9% were dissatisfied with the others of appellations. 3. Most patients preferred to be called '-ssi' by nurses(77.3%) and doctors(78.7%) respectively. The dominant reason being accuracy(45.8%), naturalness(33.9%) for nurses and 43.8% and 45.4% respectively for doctors. 4. The relationship between the type of appellations requested of nurses and general characteristics showed that age($X^2=83.91%$ p=.000), level of education($X^2=33.35$ p=.000), and occupation($X^2=38.22$ p=.033) were related to the type of appellation. The type of appellation requested of doctors was related to the age($X^2=72.56$ p=.000), level of education($X^2=30.01$ p=.000), and occupation($X^2$=42.90 p=.010). Generally, '-ssi' was requested of doctors and nurses, but lower age group or higher age group(over 61), those in elementary schools or elementary school graduates snd students preferred being called by their first names or grandfather, grandmother. From the results above, we can see that the most general type of appellation used for patients by the medical staff is '-ssi' and most patients were satisfied with the appellation but, the reason being that such appellations were accepted without concern. This shows that most are not adequately satisfied with the appellation. Only a small number of people use '-nim' and '-teacher' but is the preferred and frequently used types of appellation. Therfore, a continuous research of appellations used for patients with patients using '-nim' and an investigation with nurses' opinions of appellations for patients as the subject are required.

• Communications of the Korean Mathematical Society
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• v.27 no.2
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• pp.317-326
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• 2012

We consider $N(k)$-quasi Einstein manifolds satisfying the conditions $C({\xi},\;X).S=0$, $\tilde{C}({\xi},\;X).S=0$, $\bar{P}({\xi},\;X).C=0$, $P({\xi},\;X).\tilde{C}=0$ and $\bar{P}({\xi},\;X).\tilde{C}=0$ where $C$, $\tilde{C}$, $P$ and $\bar{P}$ denote the conformal curvature tensor, the quasi-conformal curvature tensor, the projective curvature tensor and the pseudo projective curvature tensor, respectively.