• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2007.10a
• /
• pp.200-203
• /
• 2007

Devices of junction barrier schottky(JBS) structure using 4H-SiC substrates with wide energy band gaps was designed and fabricated. As a measurement results, the device of reverse I-V characteristics was shown as more than 1000 V, its design optimum length of p-grid was $3{\mu}m$ space. In this paper, I-V characteristics was modeled by using of device fabricated process conditions parameters and it was extracted that the I-V property parameters, and it was compared and analyzed with between device parameters and model parameters.

• Journal of Sensor Science and Technology
• /
• v.3 no.3
• /
• pp.22-27
• /
• 1994

Design of potentiostat and I-V converter for micro pO2 sensor is described. Also, The operation of the designed circuit, in connection with the eqivalent model of micro pO2 sensor, is simulated. The potentiostat showed low output resistance of $l.1k{\Omega}$ and input voltage range of $-3{\sim}2.5V$. And the I-V converter showed low input resistance of $30{\Omega}$ and good linearity between input and output.

• The Journal of Internal Korean Medicine
• /
• v.33 no.1
• /
• pp.14-25
• /
• 2012

Objectives : To observe physiological changes during clinical acupuncture treatment. Methods : We recruited 40 healthy volunteers who had experienced an acupuncture treatment at least once within the past three years. The experimental group was divided into four groups according to the needling site and frequency of electrical stimulation. Sites consisted of abdomen and legs. Frequencies consisted of 100 Hz and 2 Hz. The procedures of experimental treatment consisted of seven phases, Resting I phase (Resting I), Needle insertion phase (Insertion), Maintenance of needle insertion I phase (Maintain I), Electrical stimulation phase (ES), Maintenance of needle insertion II phase (Maintain II), Needle removal phase (Removal) and Resting II phase (Resting II). We measured the surface electromygraphy (SEMG) through an electrode on the frontalis muscle during all phases consecutively. Results : When SEMGs of all seven phases were analyzed, they significantly increased or decreased according to phases. SEMGs of Insertion, Maintain I, ES and Maintain II phase significantly increased more than RestingI in abdomen and legs groups. SEMGs of the abdomen group were measured as being $4.78{\pm}0.74{\mu}V$ on Resting I, $16.48{\pm}3.97{\mu}V$ on Insertion, $46.31{\pm}10.56{\mu}V$ on Maintain I, $45.88{\pm}9.72{\mu}V$ on ES, $45.56{\pm}9.69{\mu}V$ on Maintain II, $18.76{\pm}3.05{\mu}V$ on Removal, and $3.75{\pm}0.65{\mu}V$ on Resting II. SEMGs of the legs group were measured as being $3.34{\pm}0.35{\mu}V$ on Resting I, $12.11{\pm}1.76{\mu}V$ on Insertion, $36.74{\pm}6.99{\mu}V$ on Maintain I, $33.57{\pm}6.30{\mu}V$ on ES, $32.66{\pm}6.03{\mu}V$ on Maintain II, $14.08{\pm}2.15{\mu}V$ on Removal, and $2.88{\pm}0.32{\mu}V$ on Resting II. Conclusions : SEMG changed differently according to processes of acupuncture. Electrical stimulation showed different change of SEMG. Thus, acupuncture treatment may change the status of the autonomic nervous system.

• Journal of the Korean Chemical Society
• /
• v.18 no.3
• /
• pp.202-209
• /
• 1974

Polarographic behaviors of copper and cadmium complexes with 2,2'-bipyridine and ethylenediamine in acetonitrile have been investigated by the DC and AC polarography. The reduction processes are estimated as follows; $Cu(II)-bipy. \;complex\;{\longrightarrow^{e^-}_{E_{1/2}\risingdotseq+0.1V}}\;Cu(I)-bipy.\;complex\;{\longrightarrow^{e^-}_{E_{1/2}=-0.43V}}\;Cu(Hg)$$Cu(II)-en.\;complex\;{\longrightarrow^{e^-}}\;Cu(I)-en.\;complex\;{times}\;{\longrightarrow^{e^-}_{E_{1/2}=-0.56V}}\;Cu(Hg)$$Cu(II)-bipy. \;complex\;{\longrightarrow^{e^-}_{E_{1/2}=-0.57V}}\;Cu(I)-bipy.\;complex\;{\longrightarrow^{2e^-}_{E_{1/2}=-0.97V}}\;Cd(I)-bipy\;complex$$Cu(II)-en.\;complex\;{\longrightarrow^{e^-}_{E_{1/2}=+0.05V}\;Cu(I)-en.\;complex{\longrightarrow^{e^-}_{E_{1/2}=-0.92V}}\;Cu(Hg)$ The limiting currents of all steps are controlled by diffusion. The number of ligand and the dissociation constant for Cu(Ⅰ)-bipy. complex were found to be n = 2 and $K_d=(1.5{\pm}0.1){\times}10^{-7}$, respectively.

• Proceedings of the KIEE Conference
• /
• 1997.07c
• /
• pp.1118-1120
• /
• 1997

This paper presents a simple method for evaluating of voltage stability using the line flow equation. Line flow equations ($P_{ij}$, $Q_{ij}$) are comprised of state variable, $V_i$, ${\delta}_i$, $V_j$ and ${\delta}_j$, and line parameter, r and x. Using the feature of polar coordinate, these becomes one equation with two variables, $V_i$ and $V_j$. Moreover, if bus j is slack or generater bus, which is specified voltage magnitude, it becomes one equation with one variable $V_i$, that is, may be formulated with the second-order equation for $V_i^2$. Therefore, multiple load flow solutions may be obtained with simple computation, and the formulated equation used for approximately evaluating of voltage stability limit considering line flow sensitivity. The proposed method was validated to 2-bus and IEEE 6-bus system.

• Journal of radiological science and technology
• /
• v.7 no.1
• /
• pp.85-92
• /
• 1984

It is a esperimental report to investigation for optimum window-width on radionuclides $^{131}I\;and\;^{198}Au$ The obtained results were as follow; 1. In case of $^{131}I$, 1) The lowest counts produced at the window-width of 10KeV and 20KeV. 2) The count rate, more increased, when the window-width more opened, but the counting efficiency is very good between 70KeV and 130KeV window-width (19.23% -35.71% about the peak energy). 3) The heighest counting rate per KeV of window appeared at 130KeV window-width. 4) BKG counts increased proportionally to the wider window as 5.473 + 0.016 cpm. 2. In case of $^{198}Au$ 1) The lowest counts appeared at 10KeV and 20KeV window. 2) Count rate more increased, when window-width more opened, but the counting efficiency is very good between 80KeV and 140KeV window (19.46% - 34.06% about the peak energy). 3) The highest counting rate per KeV of the window appeared at 140KeV window. 4) BKG counts increased proportionally to the wider window-width as 4.74 + 1.09 cpm.

• Communications of the Korean Mathematical Society
• /
• v.20 no.3
• /
• pp.427-436
• /
• 2005

Let (R, m) be a 2-dimensional regular local ring with algebraically closed residue field R/m. Let K be the quotient field of R and v be a prime divisor of R, i.e., a valuation of K which is birationally dominating R and residually transcendental over R. Zariski showed that there are finitely many simple v-ideals $m=P_0\;{\supset}\;P_1\;{\supset}\;{\cdotS}\;{\supset}\;P_t=P$ and all the other v-ideals are uniquely factored into a product of those simple ones. It then was also shown by Lipman that the predecessor of the smallest simple v-ideal P is either simple (P is free) or the product of two simple v-ideals (P is satellite), that the sequence of v-ideals between the maximal ideal and the smallest simple v-ideal P is saturated, and that the v-value of the maximal ideal is the m-adic order of P. Let m = (x, y) and denote the v-value difference |v(x) - v(y)| by $n_v$. In this paper, if the m-adic order of P is 2, we show that $O(P_i)\;=\;1\;for\;1\;{\leq}\;i\; {\leq}\;{\lceil}\;{\frac{b+1}{2}}{\rceil}\;and\;O(P_i)\;=2\;for\;{\lceil}\;\frac{b+3}{2}\rceil\;{\leq}\;i\;\leq\;t,\;where\;b=n_v$. We also show that $n_w\;=\;n_v$ when w is the prime divisor associated to a simple v-ideal $Q\;{\supset}\;P$ of order 2 and that w(R) = v(R) as well.

• Korean Journal of Mathematics
• /
• v.14 no.2
• /
• pp.203-215
• /
• 2006

In this note the notion of interval-valued fuzzy BG-algebras (briefly, i-v fuzzy BG-algebras), the level and strong level BG-subalgebra is introduced. Then we state and prove some theorems which determine the relationship between these notions and BG-subalgebras. The images and inverse images of i-v fuzzy BG-subalgebras are defined, and how the homomorphic images and inverse images of i-v fuzzy BG-subalgebra becomes i-v fuzzy BG-algebras are studied.

• Proceedings of the KIPE Conference
• /
• 2018.11a
• /
• pp.217-218
• /
• 2018

Droop control method is the conventional controller to solve the problem of current sharing error and voltage deviation that can occur in parallel connection of DC-DC converter. This paper compared V-I droop control with I-V droop control, which based on communication and confirmed the results through experiments.

• Korean Security Journal
• /
• no.2
• /
• pp.193-210
• /
• 1999

Through the case study, this thesis suggests several methods to prevent the assassination attempt on V.I.P. by examining what makes assassin assassinate V.I.P. and analyzing various kinds of motive and type. The paper, aiming to prevent assassination on V.I.P. consists of four chapters. Chapter I, the introductory chapter of this thesis, describes regarding the V.I.P. protection environment surrounding our nation. Chapter II concerns various kinds of motive and type of assassination. Under the title 'Point and Provision of Assassination' , chapter III shows several example case studies on assassinations occurred in our nation and foreign countries and suggests it's points and the lesson these case studies give us. The fourth chapter concludes with a bibliography. The conclusion of this study can be summarized in a word as following proverb; 'Providing is Preventing'.