• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.686-688
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• 2013

• Proceedings of the Korean Magnestics Society Conference
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• 2015.11a
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• pp.95-95
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• 2015

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.2 no.2
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• pp.63-68
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• 2009

We study on the transient response in non-uniform microstrip lines with optically controlled microwave pulses. The transient response of the microwave pulses in plasma layer has been evaluated by reflection function of dielectric microstrip lines. The variation of characteristic response in plasma layer with localized pulses has been evaluated analytically. Reflection the change of the reflection amplitude has been observed.

• Polymer Science and Technology
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• v.25 no.3
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• pp.205-213
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• 2014

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.11
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• pp.136-141
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• 1994

In this paper, we implemented an opto-electronical signal processing system for the edge detection using the diffusion neural network. The diffusion neural network performs a Gaussian and DOG operation efficiently by the diffusion process. The diffusion neural network is more efficient than the LOG masking method in hardware implementation because it has a few connections and the connection weights are fixed-valued. We implemented a diffusion neural network using the characteristics of the light intensity distribution function which is similar to the Gaussian function. We have shown that the system can detect the edge of an image exactly through the experimental results.

• Journal of the Korean Vacuum Society
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• v.18 no.2
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• pp.116-126
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• 2009

It is becoming more difficult to improve the device operating speed by shrinking the size of semiconductor devices. Therefore, for a new leap forward in the semiconductor industry, the advent of silicon opto-electronic devices, i.e., silicon photonics is more desperate. Silicon Avalanche LED is one of the prospective candidates to realize the practical silicon opto-electronic devices due to its simplicity of fabrication, repeatability, stability, high speed operation, and compatibility with silicon IC processing. We conducted the measurement of the electrical characteristics and the observation of the light-emitting phenomena using optical microscopy. We analyzed the influence of the design elements such as the shape of the light-emitting area and the depth of the $n^{+}-p^{+}$ junction with simple device modeling and simulation. We compared the results of simulation and the measurement and explained the discrepancy between the results of the simulation and the measurement, and the suggestions for the improvement were given.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.04b
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• pp.97-98
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• 2009

Here, we describe a versatile strategy for precise control of the optoelectrical properties of the single walled carbon nanotube (SWNT)/silane binder hybrid films by noncovalent hybridization. Stable SWNT/silane binder solutions were prepared by direct mixing of high concentration CNT solutions and silane sol solutions. The critical binder content was determined by varying the amount of binder in the SWNT/binder solutions. A binder content of 50 wt% was used to prepare the other SWNT/binder solutions. This study demonstrates how the intermolecular interactions between the SWNTs and the silanes can affect the conductivity of the CNT/binder network films by characterizing the optoelectrical and Raman spectroscopic properties of the SWNT/silane films containing silane binders with various functional groups. The use of the PTMS binder with phenyl groups was found to be most effective in the fabrication of transparent and conductive films on glass substrates. Such a precise control of the optoelectrical properties of SWNT/binder films can be useful to fabricate the high performance conductive thin films, with ramifications for understanding the fundamental intermolecular interaction in carbon materials science.

• Journal of the Optical Society of Korea
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• v.18 no.5
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• pp.436-441
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• 2014

We have demonstrated an amplified wavelength-division multiplexed (WDM) passive optical network (PON) by using broadband light source (BLS) seeded optical sources and chirped fiber Bragg gratings (FBGs) based dispersion compensators. Chirped FBGs located at central office (CO) were fabricated and used as channel-by-channel dispersion compensators in order to mitigate the dispersion-induced distortion of both downstream and upstream signals. Owing to a low insertion loss of chirped FBG based dispersion compensator, the optical signal-to-noise ratio (OSNR) of the downstream signal could be improved to be ~28 dB. Thus, we re-confirmed that an error-free transmission of 1.25 Gb/s signals over a 100 km single-mode fiber (SMF) link could be achieved with a proposed amplified WDM-PON architecture. We have also evaluated the impact of various noises on the system's performance, and found that the low OSNR of the downstream signal would be a main limiting factor on the maximum reach of the proposed amplified WDM-PON architecture. From the measured ~13 dB improvement in OSNR of the downstream signal compared to our previously-proposed dispersion compensating module based scheme, we believe that the proposed architecture can accommodate a reach of longer than 100 km SMF link easily.

• Korean Journal of Metals and Materials
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• v.49 no.6
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• pp.505-513
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• 2011

A magnetic device which enables the application of a strong and uniform magnetic field to thin film during sputtering was designed for controlling the magnetic anisotropy using a three dimensional finite element method, and the effects of the external magnetic field on the magnetic properties of sputtered thin films were investigated. Both the intensity and the uniformity of the magnetic flux density in the sputter zone (50 mm ${\times}$50 mm) was dependent on not only the shape and size of the magnet device but also the magnitude of stray fields from the magnet. For the magnet device in which the distance between two magnets or two pure iron bars was 80-90 mm, the magnetic flux density along the direction normal to the external magnetic field direction was minimum. The two row magnets increased the magnetic flux density and uniformity along the external magnetic field direction. An Fe thin film sputtered using the optimized magnet device showed a higher remanence ratio than that fabricated under no external magnetic field.

• Journal of the Microelectronics and Packaging Society
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• v.20 no.3
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• pp.75-80
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• 2013

According to advance of electronic packaging technology, electronic package becomes smaller. Miniaturization of package causes the temperature rise of package. This can degrade life of electronic device and generate the failure of electronic system. In this study, we proposed a new semi-embedded structure with micro pattern for maximizing heat dissipation. A proposed structure showed the characteristics which have maximum temperature lower than $20^{\circ}C$ compared with conventional structure. And also, in view of thermal stress and strain, our structure showed a remarkably low value compared with other ones. We expect that the new structure proposed in this work can be applied to an flip-chip package of the future.