• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.2
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• pp.383-393
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• 2010

DVC (Distributed Video Coding) allows us to explore the video statistics at the decoder side, resulting in a less complex encoder and more complex decoder. In this approach, it is important to generate a good prediction to the current Wyner-Ziv frame, called side information, which plays a crucial role in the overall performance of a DVC system. Conventional MCFI (motion compensated frame interpolation) techniques, which explore temporal correlations between neighbor frames of the current frame, preform the block-based or object-based motion estimation, but, they do not include the basis frame for the Wyner-Ziv frame. This paper proposes an efficient way to get better side information, by finding the average frame between neighbor frames and by comparing adaptively the candidate blocks. Through computer simulations, it is shown that the proposed method can improve the performance up to 0.4dB and provide better subjective and objective visual qualities in Wyner-Ziv CODEC.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.494_495
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• 2009

This paper presents a study of DFIG wind power generation system for real-time simulation. For real-time simulation, the real-time digital simulator (RTDS) and its user friendly interface simulation software (RSCAD) are used. 2.2MW grid-connected variable speed DFIG wind power generation system is modeled and analyzed in this study. Stator-flux oriented vector control scheme is applied to stator, rotor side converter control, and back-to-back PWM converters are implemented for the decoupled control. The real-wind speed signal extracted by an anemometer is used for realistic and accurate simulation analysis. Block diagrams for DFIG and control scheme of stator, rotor-side are introduced. Real-time simulation cases are carried out and analyzed for the validity of this work.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.278-278
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• 2006

Polymer architectures containing metal-ligands in their side chain represent a diverse approach to generating multi-functional materials. The ability to define a versatile synthetic platform will enable many chemistries and architectures to be studied. This report describes our latest efforts to prepare these unique polymers; random and block copolymers have been successfully prepared. Subsequent functionalization with metal ions leads to a variety of properties including metal induced gelation, solvochromic and metal ion sensors, and unique hierarchical self-assembled structures.

• Transactions of Materials Processing
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• v.4 no.3
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• pp.267-281
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• 1995

Preform design is one of the critical fields in metal forming. The finite element method(FEM) has been effective in designing preforms and process sequence, for which the backward tracing scheme of the rigid-plastic FEM has been explored. In this work a program using the backward tracing scheme by the rigid-plastic FEM is developed for three-dimensional plastic deformation, which is an extension of the scheme from two-dimensional cases. The calculation of friction between workpiece and die, and handling of boundary conditions during backward tracing require sophisticated treatment. The developed program is applied to upsetting of a rectangular block and to side pressing of a cylindrical workpiece. The results of the two applications show feasibility of the program on three-dimensional plastic deformation.

• Journal of Electrical Engineering and Technology
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• v.5 no.1
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• pp.61-69
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• 2010

This paper presents a study of a DFIG wind power generation system for real-time simulations. For real-time simulations, the Real-Time Digital Simulator (RTDS) and its user friendly interface simulation software RSCAD are used. A 2.2MW grid-connected variable speed DFIG wind power generation system is modeled and analyzed in this study. The stator-flux oriented vector control scheme is applied to the stator/rotor side converter control, and the back-to-back PWM converters are implemented for the decoupled control. The real-wind speed signal extracted by an anemometer is used for a realistic, reliable and accurate simulation analysis. Block diagrams, a mathematical presentation of the DFIG and a control scheme of the stator/rotor-side are introduced. Real-time simulation cases are carried out and analyzed for the validity of this work.

• Journal of Korea Society of Industrial Information Systems
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• v.7 no.4
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• pp.1-8
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• 2002

Attacks have been proposed that use side information as timing measurements, power consumption, electromagnetic emissions and faulty hardware. Elimination side-channel information of prevention it from being used to attack a secure system is an active ares of research. In this paper, differential power analysis techniques used to attack DES are compared and analyzed finally, we propose a software prevention idea of DPA attack for DES-like ciphers.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.10a
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• pp.281-288
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• 1999

This paper studied the efficiency of retrofitting of reinforced concrete structure which was not designed to endure an earthquake. The earthquake in Kobe Japan showed that there was a great possibility of having an earthquake even in big city and the damages were concentrated on mid or low story buildings which were not considered to be protected from an earthquake, . This experiment used reinforced concrete structure which restrained side-by-side displacement to test durability against an earthquake. This study deals with the structural performance of reinforced concrete frame structures strengthened with steel materials.

• ETRI Journal
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• v.43 no.4
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• pp.746-757
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• 2021

Side-channel attacks pose an inevitable challenge to the implementation of cryptographic algorithms, and it is important to mitigate them. This work identifies a novel data encoding technique based on 1-of-4 codes to resist differential power analysis attacks, which is the most investigated category of side-channel attacks. The four code words of the 1-of-4 codes, namely (0001, 0010, 1000, and 0100), are split into two sets: set-0 and set-1. Using a select signal, the data processed in hardware is switched between the two encoding sets alternately such that the Hamming weight and Hamming distance are equalized. As a case study, the proposed technique is validated for the NIST standard AES-128 cipher. The proposed technique resists differential power analysis performed using statistical methods, namely correlation, mutual information, difference of means, and Welch's t-test based on the Hamming weight and distance models. The experimental results show that the proposed countermeasure has an area overhead of 2.3× with no performance degradation comparatively.

• Proceedings of the KWS Conference
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• 2006.10a
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• pp.283-285
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• 2006

Non Destructive Examination for welds is one of the most important processes to ensure the integrity of facilities of Nuclear power plants. An automated ultrasonic testing program is developed for welding inspection. A test block with side EDM notch is inspected with this program. This paper shows that the developed automated ultrasonic testing program is quite effective.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.4
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• pp.103-112
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• 1990

For this study, the full-scale model of Chumsungdae was selected as an object, and various photographs were obtained with metric camera for forming circular strips and blocks. The accuracies were analyzed according to the change of object distance and different configuration of control points by bundle adjustment, and the characteristics of results obtained through combined strips were drawn. This thesis suggests optimal analysis technique of cylindrical structures requiring all-side analysis such as cultural properties. As a result, it is possible to use control points positioned on only any one-side for all-side analysis, and control configuration is more important rather than the number of control points for increasing accuracy. In addition, it is desirable to locate control points in X, Y and Z plane uniformly, and it was shown as object distance was shorten and the number of combined strips increases, the accuracy of results was improved considerably.