• Journal of the Semiconductor & Display Technology
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• v.18 no.2
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• pp.29-31
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• 2019

The ZTO/p-Si thin film was produced and investigated for tunneling phenomena caused by the interface characteristics of the depletion layer. ZTO thin film was deposited and heat treated to produce barrier potentials by the depletion layer. The negative resistance characteristics were shown in the thin film of ZTO heat treated at $100^{\circ}C$, and the insulation properties were the best. Current decreased in the negative voltage direction by nonlinear show key characteristics, and current decreased in tunneling phenomenon by negative resistance in the positive voltage direction. Heat treated at $100^{\circ}C$, the ZTO thin film has increased barrier potential in the areas of the depletion layer and therefore the current has increased rapidly. The current has decreased again as we go beyond the depletion layer. Therefore, tunneling can be seen to make insulation better. In the ZTO thin film heat treated at $70^{\circ}C$ without tunneling, leakage current occurred as current increased at positive voltage. Therefore, tunneling effects by negative resistance were found to enhance insulation properties electrically.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.1
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• pp.61-73
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• 2016

Water mass distribution and currents were investigated off the east coast of Korea near the Hupo Bank using the CTD and ADCP data from June to August 2010. The typical water masses were: (1) Tsushima Surface Water (TSW) from the East Korean Warm Current (EKWC) in the surface layer, (2) a shallow thermocline at 20-30 m depth, (3) Tsushima Middle Water (TMW) of high salinity (>34.2) below the pycnocline, (4) North Korean Cold Water (NKCW) of low salinity (<34.05) and low temperature (<4°C) in the lower layer. In June, a double eddy was observed in which a cold filament intruded cyclonically from the south around a pre-existing cold-core eddy. A burst of strong southward current was recorded in mid-August due to a warm filament from the meandering EKWC. Current in the N-S direction was predominant due to topographic effects, and the direction of the northward EKWC was frequently reversed in its direction due to the eddy-filament activity, whereas the influence of the wind was not noticeable. The vertical structure of the current was of a two-layer system, with the northward EKWC in the upper layer and weak southward flows corresponding to the North Korean Cold Current (NKCC) in the deeper layer.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.555-559
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• 2001

Feed and spindle motor currents are used toi monitor the cutting process practically. The sensitivity of spindle drive system is lower than that of feed drive system, but the cutting torque is represented well by the spindle motor current. During multi-axis cutting, it is difficult to calculate the resultant cutting force using feed motor currents, because each feed force is reflected by each axis feed motor current with different time delay. It is also difficult to compensate the frictional torque using the feed motor current, because the magnitude of the frictional torque is dependent of the feedrate, table position, and cutting direction. On the other hand, cutting torque can be estimated well using spindle motor current which is independent of the cutting direction.

• Progress in Superconductivity and Cryogenics
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• v.1 no.1
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• pp.38-41
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• 1999

Strands composing multistage superconducting cables for AC power applications have twisted structure in each stage for lower AC loss and higher stability. So, when transport currents flow in a cable, each strand is exposed to longitudinal and azimuthal magnetic fields produced by transport current flowing in strand itself and Iongitudinal and transverse magnetic fields by transport current flowing in twisted cable. In this paper. we study the influence on self field lesses generated in second stage superconducting cable for different twist direction of filaments in a strand considering twist of strands in cables.

• Proceedings of the IEEK Conference
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• 2001.06e
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• pp.127-130
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• 2001

In this paper, we describes a method of estimating traveling direction of a autonomous vehicle. For the development of autonomous vehicle, it is important to detect road lane and to reckon traveling direction. The object of a propose algorithm is to perform lane detection in real-time for standalone vision system. And we calculate efficent traveling direction to find steering angie for lateral control system. Therefore autonomous vehicle go forward the center of lane by adjusting the current steering angle using traveling direction.

• Journal of Magnetics
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• v.11 no.2
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• pp.87-89
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• 2006

CoFeV thin film alloys were fabricated by electrodeposition, and the dependences of their magnetic properties on the current density were investigated using an X-ray diffractometer and a vibrating sample magnetometer. The deposited Co increased from about 45 to 60 wt.% with increasing current density until $25mA/cm^2$ whereas the deposited Fe decreased from about 55 to 40 wt.% with increasing current density until $25mA/cm^2$. The deposited V, about 2 wt.%, was independent of the current density. The current efficiencies of electrodeposition decreased linearly from about 40 to 29% with increasing current density. The X-ray diffraction measurement showed that all peaks of the CoFeV films were consistent with those of a typical Co hcp and Fe bcc mixed phase. An increase in the current density decreased the grain size and increased the lattice constant. The saturation magnetization increased from about 2.2 to 2.5 T with increasing current density. The coercivity measured in the perpendicular direction decreased from 260 to 120 Oe with increasing current density; a drastic drop of 60 Oe occurred at $5mA/cm^2$. The coercivity measured in the in-plane direction remained almost unchanged, at about 20 Oe, with increasing current density.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.1327-1329
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• 2000

The thyristor among the power-semi-conductor elements, which has large current capacity and high voltage, is used widely nowadays. When the thyristor was being used to the long time, this element may be able to arise the system trip caused by changing the characteristic and dropping the performance. Therefore, it would be necessary to analyze the characteristic of element to maintain the stable operation of the system. In oder to analyze this characteristic, it would be need to test forward direction, reverse direction and leakage current by supplying the half-sine wave voltage. Among these testing, transient current condition is generated from the testing of leakage current. This transient current may be the main factor of the error in the precise measurement of leakage current. Therefore, this paper analyzes the relationship between supply voltage and transient current in measuring leakage current of the SCR, and then suggests the condition and cause of transient current as appearing the leakage current in the testing the leakage current.

• Electrical & Electronic Materials
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• v.9 no.7
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• pp.674-679
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• 1996

Using the home made Kuhn type LB (Langmuir - Blodgett) film's deposition apparatus, We measured the displacement current of monolayer film on the water surface. The obtained displacement current had each different pattern by the kind of solution while varying pressure of the monolayer. Solution of 4 - octyl - 4' - (5 - carboxyl - pentamethyleneoxy ) - azobenzene (8A5H) and stearic acid (CH$_{3}$(CH$_{2}$)$_{16}$COOH) (C18) were spreaded at the air water interface respectively, and the current induced by the dynamic behavior of molecules were pressed by barrier. Displacement current of 8A5H measured small current than C18 at same condition and it was positive direction when increasing pressure but it was negative direction when decreasing pressure. Also, Two patterns of displacement current were symmetrical form and appeared repeatedly. The C18 has unsymmetrical form of displacement current and weak current when decreasing pressure (expansion). The C18 molecules have two distinct peak values of displacement current that show that the orientations of molecules were changed largely at this points. From these results, we obtained that the 8A5H has more elasticity than the C18.8.C18.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.389-392
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• 2001

In this paper, we have explained electrical characteristics of a step-down Rosen type piezoelectric transformer for AC-adapter. When the electric voltage is applied to the driving piezoelectric vibrator polarized in the longitudinal direction, then output voltage is generated at the generating piezoelectric vibrator polarized in the thickness direction due to the piezoelectric effects. Output voltage and current from a 11-layered and a 13-layered piezoelectric transformer were measured under the various conditions of loads and frequencies. We measured resonant frequency from impedance curve. It was shown from experiments that output voltage has increased and resonant frequency has changed according to various resistor loads. Output current has changed inversely proportional to resistances.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.1366-1369
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• 2010

Along with the increasing need of sea development, the hydraulic stability of seabed structure on a soft seafloor ground is becoming an issue in the course of seaside development recently. However, the movement and hydraulic resistance or hydraulic stability of seafloor ground are mutually coupled with various phenomena, and there has been no clear proof for the issue, which makes it difficult to forecast. Furthermore, most researches are focused on hydraulic variables and the conditions of marine external force, while there have been few researches into the assessment in consideration of the type of a seafloor ground and the geotechnical characteristics. In addition, according to the periodic change of the flow direction, possible changes in hydraulic resistance performance of the seafloor deserves all the recognition. But there is no way to measure the hydraulic unstability of the sea ground due to tidal flow quantitatively. In this study, conventional hydraulic resistance measurement apparatus was improved to consider direction change of the current flow. Various artificial clayey soil specimens were made from Kaolinite and Jumunjin standard sand and hydraulic resistance tests were performed by changing the flow direction to validate the effect of the direction change on the scour of the seafloor.