• Korean Journal of Optics and Photonics
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• v.17 no.3
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• pp.285-289
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• 2006

A novel alignment-free micro-optic MZI filter has been demonstrated. The filter is composed of two fiber-pigtailed collimators and a beam-splittingplate with a periodically etched stripe pattern. We fabricated the plate through a standard lithographic formulation process by using a pyrex substrate glass with SU-8 resist coating on its one of the surfaces. The maximum insertion loss of the implemented filter was less than 2 dB over 1000 nm to 1600 nm and the extinction ratio was larger than 33 dB. The measured PDL within the 3-dB pass band of the filter was less than 0.15dB and the maximum extinction ratio variation was less than 2 dB even when the worst alignment error occured.

• Journal of the Korea Society of Computer and Information
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• v.13 no.3
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• pp.169-177
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• 2008

Grid resources are composed of various communication networks and operation systems. When a grid system searches and selects grid resources, which meet requirements of a grid user, existing grid resource selection systems are limited due to their storage methods for resource information. In order to select grid resources suitable for requirements of a grid user and characteristics of data, this paper constructs an ontology for grid resources and proposes an ontology-based grid resource selection system. This system provides an inference engine based on rules defined by SWRL to create a resource list. Experimental results comparing the proposed system with existing grid resource selection systems, such as the Condor-G and the Nimrod-G, verify the effectiveness of the ontology-based grid resource selection system with improved job throughput and resource utilization and reduced job loss and job processing time.

• Journal of Powder Materials
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• v.14 no.3 s.62
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• pp.157-164
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• 2007

An electron energy loss spectroscopy (EELS) instrument attached on transmission electron microscopy (TEM) becomes a powerful and analytical tool for extracting the noble information of materials using the enhancement of TEM images, elemental analysis, elemental or chemical mapping images, electron energy loss near edge structure (ELNES), and extended energy-loss fine structure (EXELFS). In this review, the principle and applications of EELS which is widely used in material, life, and electronic sciences were introduced.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.489-496
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• 2004

The effect of airconditioning and heating system when aircurtains installed in subway electrical rolling stock at entrance door. It blocks cold/hot air of outside. It is good for health with its blocking effect against dusts exhaust fumes, odor bugs and smoke from outside. It always maintains clean and pleasant atmosphere inside. It helps you to have health with its ever-equal temperature distribution at inside. It saves lots of maintenance cost for heating/cooling (about 86$\%$) since it cuts the loss of hot air under heating as well as of cold air under air-conditionin. Customers can feel pleasant go in and out (better than before) with the door. It is an indispensable product for the employers to cut the cost. It makes customers feel pleasant near doors, since it isnt influenced by temperature difference of cold/hot air when the door opens/closes. In electrical rolling stock passenger temperature is a lot different from that the door opens/closes. One of the main aims is to create an acceptable thermal environment without draught problem. Temperature, gradients when aircurtains installed in subway electrical rolling stock at entrance door have been studied. And the temperature measured at 0.1, 0.5, 1.3, 1.7m above the floor. It has been found that temperature, with large fluctuations caused more draught influence.

• The Journal of the Convergence on Culture Technology
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• v.6 no.2
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• pp.521-527
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• 2020

Quantum-dot cellular automata (QCA) is a technology that attracts attention as a next-generation digital circuit design technology, and several digital circuits have been proposed in the QCA environment. Content-addressable memory (CAM) is a storage device that conducts a search based on information stored therein and provides fast speed in a special process such as network switching. Existing CAM cell circuits proposed in the QCA environment have a disadvantage in that a required area and energy dissipation are large. The CAM cell is composed of a memory unit that stores information and a match unit that determines whether or not the search is successful, and this study proposes an improved QCA CAM cell by designing the memory unit in a multi-layer structure. The proposed circuit uses simulation to verify the operation and compares and analyzes with the existing circuit.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.1
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• pp.45-49
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• 2008

The development of manufacturing process of silicon (Si) ingots is one of the important issues to the growth of the photovoltaic industry. Polycrystalline Si wafers shares more than 60% of the photovoltaic market due to its cost advantage compared to mono crystalline silicon wafers. Several solidification processes have been developed by industry including casting, heat exchange method (HEM) and electromagnetic casting. In this paper, the advanced directional solidification (ADS) method is used to growth of large sized polycrystalline Si ingot. This method has the advantages of the small heat loss, short cycle time and efficient directional solidification. The numerical simulation of the process is applied using a fluid dynamics model to simulate the temperature distribution. The results of simulations are confirmed efficient directional solidification to the growth of large sized polycrystalline Si ingot above 240 kg.

• Journal of the Korea Concrete Institute
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• v.13 no.3
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• pp.244-250
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• 2001

One of the reasons for brittle failure in reinforced concrete structures subjected to severe earthquake is due to large slip between reinforcing steel and concrete. This study aims to evaluate effects of deformation patterns of ribbed reinforcing bars on bond under cyclic loading. Bond test specimens were constructed with machined bars to test the newly developed reinforcing bars with high relative rib areas. The degree of confinement is also another key parameter in this bond test. From the test results under monotonic and cyclic loading, bond strength and stiffness were evaluated. Bond strength and bond stiffness increase as relative rib areas under cyclic loading for specimens highly confined by transverse reinforcement. The increase rates of the bond performance under cyclic loading are larger than those of specimens under monotonic loading. The developed bars with high relative rib areas will contribute for better bond performance for reinforced concrete structures subjected to severe seismic loadings.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.2
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• pp.165-170
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• 1986

Various cell wall polysaccharides such as IAP(ionically associated pectin), CBP(covalently bounded pectin), HF(hemicellulosic fraction) and CF(cellulosic fraction) were fractionated by chemical method from hot pepper fruit cell wall during ripening and softening. And then, the composition of the polysaccharides were determined. The IAP and CBP were composed of $65{\sim}88%$ polyuronide, $4{\sim}29%$ hemicellulose and $0.3{\sim}2.1%$ cellulose. And hemicellulose also contained $8{\sim}13%$ polyuronide and $0.1{\sim}1.1%$ cellulose. The containing ratio of hemicellulose associated with the CBP was higher than IAP. All of the polysaccharides except CF decreased by the turning stage showed softening. The polyuronide made up IAP changed little but, that of the CBP increased during softening owing mainly to decrease of the hemicellulose that was bounded to the CBP and was mostly linked to galactose.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.3
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• pp.509-517
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• 2015

Side Channel Analysis of applying the power-consumption was known as effective method to analyze the key of security device based on chip. The precedential information of power-consumption was measured by the voltage distribution method using by series connection of resistor. This method was dependent on the strength of the voltage. If the voltage cannot be acquired much information which is involved with the key, the information of power-consumption significantly might be influenced by noise. If so, some of the information of power-consumption might be lost and distorted. Then, this loss can reduce the performance of the analysis. For the first time, this paper will be introduced the better way of the improvement with using the method of Current to Voltage Converter with OP-Amp. The suggested method can reduce the effect of the noise which is included in the side channel information. Therefore we can verify the result of our experiments which is provided with the improvement of the performance of side channel analysis.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37A no.9
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• pp.728-737
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• 2012

An analytical method for identifying terrestrial broadcasting coverages is proposed for a terrestrial broadcasting transmission system adopting a hierarchical modulation technique. Bit Error Rates(BERs) are derived for hierarchically modulated non-uniform QAM constellations based on the Q-function analysis in AWGN environments. The derived BERs depend on the hierarchical modulation factor ${\alpha}$(HMF) and could be mapped to the broadcasting coverages according to the link budget analysis based on the log-distance path loss model. Finally the broadcasting coverage ratios for high priority(HP) streams and low priority(LP) streams are calculated and presented for the determination of the HMF.