• Transactions of the Society of Information Storage Systems
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• v.3 no.3
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• pp.123-125
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• 2007

We report the readout stability improvement results of super-resolution near field structure (Super-RENS) writeonce read-many (WORM) disk at a blue laser optical system. (Laser wavelength 405nm, numerical aperture 0.85) By using diffusion barrier structure (GeSbTe sandwiched by GeN) and high transition temperature recording material ($BaTiO_3$), material diffusion of phase change layer and recording mark degradation were greatly improved during high power (Pr=2.0mW) readout process up to $1{\times}10^5$ times.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.12
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• pp.1894-1899
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• 1990

We present an electro-optical voltage sensor. Crystalline bismuth germanate(BI4Ge3O12) used as the electro-opticla crystal exhibited linear birefringences of 1.7x10**-5 to 5.4x10**-4. And these birefringences were observed to be strongly temperature dependent. In order to improve the stability of the electro-opticlal voltage sensor, crystals (Bi4Ge3=12) were annealed and a compensation method was used. After applying this compensation method to the voltage sensor, the temperature stability, pressure stability, and vibration stability of the sensor were highly improved, Noise Equivalent Voltage of this sensor was a few mV/\ulcornerz.

• Proceedings of the Materials Research Society of Korea Conference
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• 2005.05a
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• pp.140-140
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• 2005

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.280-281
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• 2011

We fabricated the devices of TFT type with the amorphous chalcogenide channel. A single device consists of a Pt source and drain, a Ti glue layer and a GeSe chalcogenide channel layer on SiO2/Si substrate which worked as the gate. We confirmed the drain current with variations of gate bias and channel size. The I-V curves of the switching device are shown in Fig. 1. The channel of the device always contains amorphous state, but can be programmed into two states with different threshold voltages (Vth). In each state, the device shows a normal Ovonic switching behavior. Below Vth (OFF state), the current is low, but once the biasing voltage is greater than Vth (ON state), the current increases dramatically and the ON-OFF ratio is about 4 order. Based on the experiments, we contained the conclusion that the gate voltage can enhance the drain current, and the electric field by the drain voltage affects the amorphous-amorphous transition. The switching device always contains the amorphous state and never exhibits the Ohmic behavior of the crystalline state.

• Bulletin of the Korean Chemical Society
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• v.15 no.1
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• pp.57-63
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• 1994

Digital simulation program for one-dimensional geometric systems of electrochemical phenomena was developed. The accuracy of the digital simulation is discussed by comparing with the known solutions. Applying this program to the linear sweep voltammetry at a planar electrode for the electrode reaction, 0 + ne${\to}$R, the accurate current functions for the reversible and totally irreversible charge transfer systems were obtained. Comparing these current functions with the simulated voltammograms for various other values of ${\alpha}$ (0.1 to 1.0) and ${\Lambda}\;(10^{-5}\;to\;10^5)$, the revised zones that are different from those proposed by Matsuda and Ayabe for the reversible and totally irreversible systems are proposed. For ${\alpha}{\ge}$0.1 the reversible zone is in ${\Lambda}{\ge}10^{1.7}$ and the totally irreversible zone is in ${\Lambda}{\le}10^{-1.7}$, where ${\Lambda}=k^{\circ}/ [D_o^{1-{\alpha}}D_R^{\alpha}(nF/RT)v]^{1/2}$.

• Journal of the Korean Physical Society
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• v.73 no.11
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• pp.1631-1636
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• 2018

Unpolarized 1.047-GeV proton inelastic scatterings from the Ni isotopes $^{62}Ni$ and $^{64}Ni$ are analyzed phenomenologically employing an optical potential model and the first-order collective model in the relativistic Dirac coupled channel formalism. The Dirac equations are reduced to $Schr{\ddot{o}}dinger-like$ second-order differential equations, and the effective central and spin-orbit optical potentials are analyzed by considering the mass-number dependence. The multistep excitation via the $2^+$ state is found to be important for the $4^+$ state excitation in the ground state rotational band for proton inelastic scatterings from the Ni isotopes. The calculated deformation parameters for the $2^+$ and the $4^+$ states of the ground state rotational band and for the first $3^-$ state are found to agree pretty well with those obtained from nonrelativistic calculations.

• Proceedings of the Korean Magnestics Society Conference
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• 2011.12a
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• pp.97-97
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• 2011

The analogy between spin configurations in spin ice materials like $Ho_2Ti_2O_7$ and proton configurations in water ice, $H_2O$, has been appreciated for many years (see Bramwell and Gingras, Science, 294, 1495, 2001). However it is only in the last few years that this equivalence has been extended into the realm of electrodynamics. In this talk I shall describe our recent experimental work that identifies magnetic charges ("monopoles"), transient magnetic currents ("magnetricity") and the universal properties expected of an ideal magnetic Coulomb gas (magnetic electrolyte - "magnetolyte"). These universal properties include the Onsager-Wien effect, "corresponding states" behaviour, Debye-Huckel screening and Bjerrum pairing. I will describe experimental results for both traditional spin ice materials ($Ho_2Ti_2O_7$, $Dy_2Ti_2O_7$) and a recently discovered system ($Dy_2Ge_2O_7$).

• Journal of the Mineralogical Society of Korea
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• v.31 no.3
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• pp.161-172
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• 2018

Multi-anvil press (MAP) is one of the high pressure apparatuses and often generates the pressure-conditions ranging from 5 to 25 GPa and temperature-conditions up to $2,300^{\circ}C$. The MAP is, therefore, suitable to explore the pressure-induced structural changes in diverse earth materials from Earth's mantle and the bottom of the mantle transition zone (~660 km). In this study, we present the experimental results for pressure-load calibration of the 1,100-ton multi-anvil press equipped in the authors' laboratory. The pressure-load calibration experiments were performed for the 14/8 step, 14/8 G2, 14/8 HT, and 18/12 assembly sets. The high pressure experiments using ${\alpha}$-quartz, wollastonitestructure of $CaGeO_3$, and forsterite as starting materials were analyzed by powder X-ray diffraction spectroscopy. The phase transition of each mineral indicates the specific pressure that is loaded to a sample at $1,200^{\circ}C$: a transition of ${\alpha}$-quartz to coesite at 3.1 GPa, that of garnet-structure of $CaGeO_3$ to perovskite-structure at 5.9 GPa, that of coesite to stishovite at 9.2 GPa, and that of forsterite to wadsleyite at 13.6 GPa. While the estimated pressure-load calibration curve is generally consistent with those obtained in other laboratories, the deviation up to 50 tons is observed at high pressure above 10 GPa. This is partly because of the loss of oil pressure at high pressure resulting from the differences in a sample chamber, and the frictional force between pressure medium and second anvil. We also report the ${\sim}200^{\circ}C/mm$ of thermal gradient in the vertical direction of the sample chamber of 14/8 HT assembly. The pressure-load calibration curve and the observed thermal gradient within the sample chamber can be applied to explain the structural changes and the relevant macroscopic properties of diverse crystalline and amorphous earth materials in the mantle.

• The Korean Journal of Air & Space Law and Policy
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• v.26 no.1
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• pp.65-92
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• 2011

Die soeben entwickelten Grundgs$\ddot{a}$tze k$\ddot{o}$nnen dazu f$\ddot{u}$hren, dass es bei Fluggesellschaften zum Abschluss mehrerer Tarifvertr$\ddot{a}$ge $\ddot{u}$ber Personalvertretungen durch verschidene Gewerkschften kommt. Dies leitet schlie${\ss}$lich zu der bereits angesprochenen Problematik der Tarifkonkurrenz $\ddot{u}$ber. Tarifkonkurrenz zeichnet sich bekanntlich dadurch aus, dass f$\ddot{u}$r dasselbe Rechtsverh$\ddot{a}$ltnis dieselbe Regelungsmaterie durch mehr als einen Tarifvertrag geregelt wird. Eine solche Tarifkonkurenz kann unabh$\ddot{a}$ngig von der Frage, ob Regelungsgegenstand betriebsverfassungsrechtlicher Normen ein betriebliches Rechtsverh$\ddot{a}$ltnis ist, auch bei dieser Art von Tarifnormen auftreten. Dabei betriebsverfassungsrechtlichen Kollektivnormen gem$\ddot{a}{\ss}$ $\S$3 Abs. 2 TVG die Tarifbindung des Arbeitgebers f$\ddot{u}$r die Anwendungsbarkeit gen$\ddot{u}$gt, wird beim Vorhandensein mehrerer solcher Tarifvertr$\ddot{a}$ge h$\ddot{a}$ufig pauschal von einer in jedem Fall aufzul$\ddot{o}$senden tarifkonkurrenz gesprochen. $\ddot{U}$berschneiden sich die Geltungsbereiche mehrerer Tarifvertr$\ddot{a}$ge $\ddot{u}$ber personalvertretungsrechtliche Fragen der im Luftbetrieb t$\ddot{a}$tigen Besch$\ddot{a}$ftigten und handelt es sich nicht um textidentische Regelungen, f$\ddot{u}$hrt indes kein Weg daran vorbei, dass eine Tarifkonkurenz besteht, die einer Aufl$\ddot{o}$sung bedarf. Die Rechtsprechung hat sich zur speziellen Fragen der Aufl$\ddot{o}$sung einer Konkurrenz betriebsverfassungsrechtlicher Tarifnormen soweit ersichtlich noch nicht ge$\ddot{a}$u${\ss}$ert. Nicht zuletzt aus diesem Grund wird in der Literatur ein buntes Spektrum an L$\ddot{o}$sungen pr$\ddot{a}$sentiert, wobei sich die meisten neueren Stellungnahmen vor allem mit Organisationstarifvertr$\ddot{a}$gen im Sinne von ${\S}$3 BetrVG besch$\ddot{a}$ftigen.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.151-151
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• 2012

A new plasma process, i.e., the combination of PIII&D and HIPIMS, was developed to implant non-gaseous ions into materials surface. HIPIMS is a special mode of operation of pulsed-DC magnetron sputtering, in which high pulsed DC power exceeding ~1 kW/$cm^2$ of its peak power density is applied to the magnetron sputtering target while the average power density remains manageable to the cooling capacity of the equipment by using a very small duty ratio of operation. Due to the high peak power density applied to the sputtering target, a large fraction of sputtered atoms is ionized. If the negative high voltage pulse applied to the sample stage in PIII&D system is synchronized with the pulsed plasma of sputtered target material by HIPIMS operation, the implantation of non-gaseous ions can be successfully accomplished. The new process has great advantage that thin film deposition and non-gaseous ion implantation along with in-situ film modification can be achieved in a single plasma chamber. Even broader application areas of PIII&D technology are believed to be envisaged by this newly developed process. In one application of non-gaseous plasma immersion ion implantation, Ge ions were implanted into SiO2 thin film at 60 keV to form Ge quantum dots embedded in SiO2 dielectric material. The crystalline Ge quantum dots were shown to be 5~10 nm in size and well dispersed in SiO2 matrix. In another application, Ag ions were implanted into SS-304 substrate to endow the anti-microbial property of the surface. Yet another bio-application was Mg ion implantation into Ti to improve its osteointegration property for bone implants. Catalyst is another promising application field of nongaseous plasma immersion ion implantation because ion implantation results in atomically dispersed catalytic agents with high surface to volume ratio. Pt ions were implanted into the surface of Al2O3 catalytic supporter and its H2 generation property was measured for DME reforming catalyst. In this talk, a newly developed, non-gaseous plasma immersion ion implantation technique and its applications would be shown and discussed.