• Journal of the Institute of Electronics Engineers of Korea SP
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• v.41 no.6
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• pp.209-220
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• 2004

The main feature of H.264 standard against conventional video standards is the high coding efficiency and the network friendliness. In spite of these outstanding features, it is not easy to implement H.264 codec as a real-time system due to its high requirement of memory bandwidth and intensive computation. Although the variable block size motion compensation using multiple reference frames is one of the key coding tools to bring about its main performance gain, it demands substantial computational complexity due to SAD (Sum of Absolute Difference) calculation among all possible combinations of coding modes to find the best motion vector. For speedup of motion estimation process, therefore, this paper proposes fast algorithms for both integer-pel and fractional-pel motion search. Since many conventional fast integer-pel motion estimation algorithms are not suitable for H.264 having variable motion block sizes, we propose the motion field adaptive search using the hierarchical block structure based on the diamond search applicable to variable motion block sizes. Besides, we also propose fast fractional-pel motion search using small diamond search centered by predictive motion vector based on statistical characteristic of motion vector.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.165-166
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• 2002

Hydrogen free diamond like carbon (DLC) films were prepared on steel substrates by using a single ion beam in a configuration that allowed sputtering of a graphite target and at the same time allowed to impact the substrate at a grazing angle. The DLC films so prepared have improved properties with increased disorder and with modest hardness that is slightly higher than previously reported values. We have studied the effects of $N_2^+$ ions implantation on such films. It is found that the implantations of nitrogen ions into DLC films lead to chemical modifications that allowed N atoms to be incorporated into the carbon network to produce a nitrogenated DLC. Nano-indentation experiments indicated that the nitrogenated films have consistently higher hardnesses ranging from 30 to 45GPa, which represents a considerable increase in surface hardness, compared with non-nitrogenated precursor films. The investigations by XPS and Raman spectroscopy suggests that the $N_2^+$ implanted DLCs had undergone both chemical and structural modifications through the incorporation of N atoms and the increased ratio of $sp^3/sp^2$ type bonding. The observed high hardness was therefore attributable to these structural and chemical modifications. This result has implication for the preparation of super hard wear resistant films required for tribological functions in devices.

• Korean Journal of Materials Research
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• v.4 no.6
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• pp.644-650
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• 1994

The submicron powders of high-purity silicon have been produced by Electrohydrodynamic Atomization. Field-emission scanning transmission electron microscopy(STEM) is used to determine the microstructure and solidification phase. .Then it is found that the droplets less than 60nm diameter are solidified as the amorphous phase. A useful and accessible characterization of atomic arrangements in amorphous solids can be given in terms of a radial distribution function. According to experimental determinations of the radial distribution function for amorphous silicon, its similarity to the crystalline structure at small radial distances indicates that the basic tetrahedral arrangement found in the diamond cubic structure of silicon must be maintained in the amorphous structure.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.4
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• pp.99-104
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• 2010

We introduce Internet TCP/IP control system to monitor the traffic volume on the traffic network system. To check the traffic volume on traffic road, we use the traffic detector system shppe of circle or diamond or rectangular. Nevertheless we use traffic detector, we will use internet addressin TCP/IP system. If we use TCP/IP control system, we acquire many good point, we achive high sircurity and low costness traffic monitoring system coming difficulty and high level position. But internet system is very easy and low cost direction. Traffic control system is very more depending on the high techinquesion and very complexity. Therefore we introducing TCP/IP internet addressing control system schemetic point.

• Journal of Broadcast Engineering
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• v.7 no.4
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• pp.317-326
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• 2002

The adaptive coding schemes in H.264 standardization provide a significant ceding efficiency and some additional features like error resilience and network friendliness. The variable block size motion compensation using multiple reference frames is one of the key H.264 coding elements to provide main performance gain, but also the main culprit that increases the overall computational complexity. For this reason, this paper proposes a selective motion estimation algorithm based on variable block size for fast motion estimation in H.264. After we find the SAD(Sum of Absolute Difference) at initial points using diamond search, we decide whether to perform additional motion search in each block. Simulation results show that the proposed method is five times faster than the conventional full search in case of search range $\pm$32.

• Journal of the Korea Society of Computer and Information
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• v.26 no.2
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• pp.89-97
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• 2021

Blockchain is designed to collect and store the data recorded on the network in one block unit, and is connected and stored back and forth, and its form is similar to how the blocks are connected, so it is called a blockchain. Many companies are trying to popularize blockchain-based services at home and abroad, and blockchains are used in various industries. This study introduces the technical characteristics of the blockchain and deals with application services utilizing the blockchain. Introducing 5 types of blockchain architecture and core technologies and introducing blockchain application services that are used in payment services, blockchain service networks, blockchain real estate platforms, identity verification, cryptocurrency, diamond distribution path tracking, and blog information recording. do. It is expected to increase the understanding of the blockchain and provide usefulness in future blockchain research and service development.

• Journal of The Korean Association For Science Education
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• v.35 no.2
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• pp.333-342
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• 2015

This study analyzes the verbal interaction patterns used in a social network activity analysis that appeared in a science inquiry activity of 31 small groups of science-gifted students consisting of 5 members each. The results of this study are as follows: The interaction patterns showed eight types. The most prevalent interaction pattern, type 1, is triangle-shaped, interacting with 3 members out of 5 without a central member. Type 2 is wye form, interacting with 4 members and with one alienated member. Type 3 is diamond-shaped, interacting with 4 members. Type 4 is ray form, interacting with 5 around a central member. Type 5 has an alienated member and interacts with 4 members around the central member. Type 6 is triangle-branched, 4 members linked to the central member. Type 7 is wye form linked all around the central member. Type 8 is wye form with a more complex link than type 7. These can be classified in two. One is the participation-type where the rest of the 4 members are linked to the central member. The other is the alienation-type where a member/members is/are alienated without a central member. The participation-type appeared in 9 groups (29%), type 4, type 6, type 7, and type 8. The alienation-type showed in 22 groups (71%), type 1, type 2, type 3, and type 5. On the basis of this study, we propose that the best number of members in a group is three. It helps prevent a free-riding effect or isolation of members. Also, we deem it more fruitful if there is a member playing a central role in a group.