• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.6
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• pp.290-295
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• 2001

The transport loss of a Bi-2223 tape exposed to external magnetic fields was investigated. The results show that the transport loss is independent on voltage lead arrangements in case the magnetization loss is compensated. A serous increase of the transport loss due to external AC magnetic field is observed. The loss is described well by dynamic resistance loss in relatively high fields, but another mechanism than the dynamic resistance must be responsible for the increase of the loss in low fields. The transport loss is also dependent strongly on the orientation of the external fields.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.3
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• pp.182-186
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• 2012

Resistance-change Random Access Memory(ReRAM) memory, which utilizes electrochemical control of metal in thin films of solid electrolyte, shows great promise as a future solid state memory. The technology utilizes the electrochemical formation and removal of metallic pathways in thin films of solid electrolyte. Key attributes are low voltage and current operation, excellent scalability, and a simple fabrication sequence. In this work, we investigated the nature of thin films formed by photo doping of $Ag^+$ ions into chalcogenide materials for use in solid electrolyte of Resistance-change RAM devices and switching characteristics according to field-effect.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.4
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• pp.441-447
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• 2007

The speed and torque control performance of the DC motor used in the industrial field is affected by the change of parameters. In particular the change of armature resistance can be greatly originated from various load conditions. Accordingly a large number of studies to estimate those problems in the servo motor control field have already been under way. In this paper, the armature resistance on the DC motor under several load and speed conditions is estimated by the Artificial Neural Network(ANN), and the validity is proven by the speed estimation of sensorless speed control system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.306-309
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• 2000

The conductive polymers, polyaniline (PANI) emeraldine base and 3, 4-polyethylene dioxythiophene (PEDOT) were synthesized and coated on the PET film primer-dealt with acryl type to find out the electromagnetic shielding effectiveness. When conductive polymer such as PANI and PEDOT is used, if the thickness of coating increases then the electromagnetic shielding effectiveness increases, too, but the visible light transmittance decreases. For PANI, when its conductivity increased, its electromagnetic shielding effectiveness increased, too. For PANI, if the surface resistance is about 140 $\Omega$/$\square$, the shielding effectiveness is about 11 dB in the far field, and about 13 dB in the near field at 1 GHz. For PEDOT, when the surface resistance is about 200 $\Omega$/$\square$, the shielding effectiveness is about 3 dB.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.122.1-122.1
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• 2011

Phosphorus is known to pile-up at the silicon surface when it is thermally oxidized. A thin layer, about 40nm thick from the silicon surface, is created containing more phosphorus than the bulk of the emitter. This layer has a gaussian profile with the peak at the surface of the silicon. In this study the pile-up effect was studied if this layer can act as a front surface field for solar cells. The effect was also tested if its high dose of phosphorus at the silicon surface can lower the contact resistance with the front metal contact. P-type wafers were first doped with phosphorus to create an n-type emitter. The doping was done using either a furnace or ion implantation. The wafers were then oxidized using dry thermal oxidation. The effect of the pile-up as a front surface field was checked by measuring the minority carrier lifetime using a QSSPC. The contact resistance of the wafers were also measured to see if the pile-up effect can lower the series resistance.

• Progress in Superconductivity and Cryogenics
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• v.25 no.3
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• pp.38-42
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• 2023

The evaluation of no-insulation (NI) high-temperature superconducting (HTS) typically uses the lumped equivalent circuit (LEC) model. Constant parameters in the NI HTS LEC model accurately predict voltage and central magnetic field at currents below the critical current. However, it is difficult to find constant circuit parameters that simultaneously satisfy the measured voltage and magnetic field under overcurrent conditions. Recent research highlights changes in contact resistance during transient conditions, which may impact power loss estimation in NI HTS coils. Therefore, we confirm the influence of contact resistance changes on loss calculation in the transient state for NI HTS coil. To achieve this, we introduce a measurement data analysis method based on the LEC model and compare it with the LEC model using constant circuit parameters.

• Magazine of the Korea Concrete Institute
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• v.17 no.3 s.86
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• pp.40-44
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• 2005

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.4
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• pp.298-302
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• 2010

We investigated the resistance change behavior of SABiT (Samsung Advanced Bump interconnection Technology) technology-applied PCB (Printed Circuit Board) with the various bump sizes and fabrication conditions. Many testing samples with different bump size, prepreg thickness, number of print on the formation of Ag paste bump, were made. The resistance of Ag paste bump itself was calculated from the Ag paste resistivity and bump size, measured by using 4-point probe method and FE-SEM (Field Emission Scanning Electron Microscope), respectively. The contact resistance between Ag paste bump and conducting Cu line were obtained by subtracting the Cu line and bump resistances from the measured total resistance. It was found that the contact resistance drastically changed with the variation of Ag paste bump size and the contact resistance had the largest influence on total resistance. We found that the bump size and contact resistance obeyed the power law relationship. The resistance of a circuit in PCB can be estimated from this kind of relationship as the bump size and fabrication technique vary.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.567-569
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• 1995

By using the ac field source which can change the applied field magnitude, frequency and dc offset field, the dynamic magnetoresistance characteristics of permalloy based multilayers which have different R-H(resistance-magnetic field) curves were monitored and compared with static magnetoresistance curves that were measured with electromagnet of VSM. Output of each sample according to the external field strength was identified and optimum bias position could be obtained.

• International Journal of Highway Engineering
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• v.7 no.4 s.26
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• pp.141-150
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• 2005

The behavior of the concrete slabs-on-grade considering the horizontal resistance at the slab bottom, which exists due to the shear resistance of the foundation and the friction between the slab and the foundation, has been investigated when the slabs-on-grade are subjected to the vertical load. Analytical formulations have been developed to include the effect of the horizontal resistance at the slab bottom, and the solutions have been obtained in the transformed field domain using the Fourier transform. Finite element formulations have also been developed using the plate bending elements and the flat shell elements. The solutions from the analytical and numerical models have been compared and showed very good agreement. The sensitivity of the horizontal resistance to the stresses of the concrete slab has been investigated with various values of the slab thickness, elastic modulus, and vertical stiffness of the foundation. The analysis results show that the horizontal resistance at the plate bottom can significantly affect the stresses of the slab.