• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.8
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• pp.1401-1405
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• 2010

We have successfully demonstrated of metal-insulator-semiconductor (MIS) capacitors with $HfO_2$/p-Si structures. The $HfO_2$ film was grown at $200^{\circ}C$ on H-terminated Si wafer by atomic layer deposition (ALD) system. TEMAHf and $H_2O$ were used as the hafnium and oxygen sources. A cycle of the deposition process consisted of 0.1 s of TEMAHf pulse, 10 s of $N_2$ purge, 0.1 s of $H_2O$ pulse, and 60 s of $N_2$ purge. The 5 nm thick $HfO_2$ layer prepared on Si substrate by ALD exhibited excellent electrical properties, including low leakage currents, no mobile charges, and a good interface with Si.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.6
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• pp.1151-1156
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• 2009

Unstable sustain discharges can occur at the bottom cells of the panel at high temperature. To solve this problem, the wall charge variation during an address period was investigated. A test panel of 7.5 inch XGA level was used and one green cell was measured. In order to realize operating condition equal to that of the bottom cells of 50 inch panel, the addressing stress pulses are applied. It seems that the resultant wall charge loss during address period increased with increase of stress time, temperature, pressure and Xe %. Wall charge loss increases with potential difference between scan electrode and address electrode, therefore wall charge loss can be minimized by the increase of scan voltage during address period.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.55 no.5
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• pp.248-253
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• 2006

The purpose of this study is to develop a portable gait-event detection system which is necessary for the cycle-to-cycle FES(functional electrical stimulation) control of locomotion. To make the system portable, we made following modifications in the gait signal measurement system. That is, 1) to make the system wireless using Bluetooth communication, 2) to make the system small-sized and battery-powered by using low power consumption ${\mu}$ P(ATmega8535L). The gait-events were analyzed in off-line at the main computer using ANN(Artificial Neural Network). The Proposed system showed no mis-detection of the gait-events of normal subject and hemiplegia subjects. The performance of the system was better than the previous wired-system.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.5-7
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• 2006

Current transformers(CTs) whose rating is selected per a full load current of a feeder in high voltage system can be easily saturated due to high fault current that may be several hundred times of the full load current of the feeder. However, the protective relay shall operate properly at the fault without mis-operation under the CT saturation. So, in selecting the CT rating, it is necessary to consider the behaviour of CT and a performance of protection scheme in condition where CT can be saturated. In this paper, a performance of CT and a degree of saturation are studied and verified whether its ratings are proper for the operation of the protective relay.

• Proceedings of the KIEE Conference
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• 2005.07d
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• pp.2873-2875
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• 2005

The optimal structure of the conventional Fuzzy Polynomial Neural Networks (FPNN)[3] depends on experience of designer. For the conventional Fuzzy Polynomial Neural Networks, input variable number, number of input variable, number of Membership Functions(MFs) and consequence structures are selected through the experience of a model designer iteratively. In this paper, we propose the new design methodology to find the optimal structure of Fuzzy Polymomial Neural Network by using Genetic Algorithms(GAs)[4, 5]. In the sequel, It is shown that the proposed Advanced Genetic Algorithms based Fuzzy Polynomial Neural Network(Advanced GAs-based FPNN) is more useful and effective than the existing models for nonlinear process. We used Medical Imaging System(MIS)[6] data to evaluate the performance of the proposed model.

• Journal of the Korean Ceramic Society
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• v.47 no.2
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• pp.146-150
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• 2010

Because the plasma display panel has used red, green and blue(RGB) phosphors, it has suffer from two intrinsic problems; 1) the cell defect due to the lack of binding force between phosphor particles and 2) mis-discharge because of difference of electrical characteristics among RGB phosphors. In order to control the mechanical and electrical properties of RGB phosphors, frit with $ZnOB_2O_3-SiO_2-Al_2O_3$ system was added to RGB phosphor as sintering additive. The mechanical properties were increased by the amount of frit. The amount of frit under 5 wt% rarely affected dielectric constant. However, there was the limit of amount because of decreasing optical properties seriously; over 3 wt% in red, over 10 wt% in green and blue.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.133-134
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• 2008

Usability study of the CU Medical "i-PAD" AED was conducted to validate the usability of the device, primarily focused on the trained user as well as the utility of the training material. Comparing these results of the trained participants to those obtained by Callejas et al. (2004), who studied video-trained users of two commercially available Philips AEDs (FR2 and HS1) using a male manikin only, the participants in this study were more successful (100% vs. 85.7%-FR2 vs. 88.9%-HS1) and faster to shock (58.5s-i-PADvs. 91s-FR2 vs. 90s- HS1). While the focus of this study was on validating ease of use for trained bystanders, the results of the untrained condition showed that, from a usability perspective, these devices perform as well as any other AEDs already approved and available for purchase for untrained bystander use, as evidenced by the comparison to various published research results

• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.221-224
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• 2000

We have successfully demonstrated metal-ferroel-ectric-insulator-semiconductor (MFIS) devices using Al/LiNbO$_{3}$/SiN/Si structure. The SiN thin films were made into metal -insulator- semiconductor (MIS) devices by thermal evaporation of aluminum source in a dot away on the surface. The interface property of MFIS from 1MHz & quasistatic C-V is good and the memory window width is about 1.5V at 0.2V/s signal voltage sweep rate. The gate leakage current density of MFIS capacitors using a aluminum electrode showed the least value of 1x10$^{-8}$ A/$\textrm{cm}^2$ order at the electric field of 300㎸/cm. And the XRD patterns shows the probability of applications of LN for MFIS devices for FeRAMs on amorphous SiN buffer layer.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.5 no.1
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• pp.69-80
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• 2010

The purpose of this study is to help the companies that have the experience and know-how about ASP and that want to go abroad. This study analyzed information and communication infrastructure of Asia, foreign investment of Korean companies, and market attractiveness, selected China, Japan, Indonesia, and Malaysia as the target for the advance into overseas markets, and then suggested the strategy for ASP overseas markets. This study can contribute ASP-related venture company or entrepreneur.

• Proceedings of the KWS Conference
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• 2006.05a
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• pp.94-96
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• 2006

Recently, steel structures have been increasing because of its brilliant features. In general, cracks and corrosion are produced due to the numerous environmental factors in steel structures. However, the validity of repair method for the damaged steel structures has not been fully verified because of its lack of safety and reliability after application. Moreover, repair method by welding inevitably involves cutting and welding processes and reliability for the safety during the processes has net been established yet. Therefore, this study carried out experiments on the fatigue strength of repair welded joints of old steel bridge to investigate the fatigue characteristics in the repair welded joints. Fatigue tests were conducted by 250kN capacity MIS with the frequency of 5Hz under amplitude loading. From the results, it is known that fatigue strength grade of the repair welded joints was satisfied with C grade which specification requires.