• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.4
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• pp.23-28
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• 2013

In this paper, we propose a simple bidirectional transmission protocol using network coding and digital Fountain codes. In particular, in the proposed scheme, two sources use digital Fountain codes to transmit their message to each other with the help of relays. Then, relays use Fountain codes and network coding to forward the source messages to both sources. To evaluate performance of the proposed protocols, we present the average total throughput over Rayleigh fading channels via Various Monte-Carlo simulations. Results show that the proposed protocol outperforms the two-way relaying transmission protocol without using network coding technique at high SNR region.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.7
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• pp.1420-1423
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• 2015

This letter considers a ship-to-ship communication system in which two ships exchange their information with the help of multiple relay ships. For the system, we propose a novel relay scheme that allows relay ships to select a method between analog network coding (ANC) and digital network coding (DNC) adaptively based on channel state information. We also provide a relay selection criterion in supporting the proposed adaptive network coding. The simulation results show that the proposed scheme outperforms the conventional scheme employing only the ANC or only the DNC.

• International journal of advanced smart convergence
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• v.2 no.1
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• pp.6-11
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• 2013

Network Coding (NC) is a new paradigm for network communication. In network coding, intermediate nodes create new packets by algebraically combining ingress packets and send it to its neighbor node by broadcast manner. NC has rapidly emerged as a major research area in information theory due to its wide applicability to communication through real networks. Network coding is expected to improve throughput and channel efficiency in the wireless multi-hop network. Many researches have been carried out to employ network coding to wireless ad-hoc network. In this paper, we proposed a dynamic queue management to improve coding opportunistic to enhance efficiency of NC. In our design, intermediate nodes are buffering incoming packets to encode queue. We expect that the proposed algorithm shall improve encoding rate of network coded packet and also reduce end to end latency. From the simulation, the proposed algorithm achieved better performance in terms of coding gain and packet delivery rate than static queue management scheme.

• Journal of Broadcast Engineering
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• v.23 no.1
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• pp.86-92
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• 2018

In this paper, we propose a method for coding history detection of digital speech signal. In digital speech communication and storage, the signal is encoded to reduce the number of bits. Therefore, when a speech signal waveform is given, we need to detect its coding history so that we can determine whether the signal is an original or an coded one, and if coded, determine the number of times of coding. In this paper, we propose a coding history detection method for 12.2kbps AMR codec in terms of original, single coding, and double coding. The proposed method extracts a speech-specific feature vector from the given speech, and models the feature vector using a deep neural network. We confirm that the proposed feature vector provides better performance in coding history detection than the feature vector computed from the general spectrogram.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.4
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• pp.374-381
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• 1991

As a diagnostic image of hospitl, the utilization of digital image is steadily increasing. Image coding is indispensable for storing and compressing an enormous amount of diagnostic images economically and effectively. In this paper adaptive two stage vector quantization based on Kohonen's neural network for the compression of cardioangiography among typical angiography of radiographic image sequences is presented and the performance of the coding scheme is compare and gone over. In an attempt to exploit the known characteristics of changes in cardioangiography, relatively large blocks of image are quantized in the first stage and in the next stage the bloks subdivided by the threshold of quantization error are vector quantized employing the neural network of frequency sensitive competitive learning. The scheme is employed because the change produced in cardioangiography is due to such two types of motion as a heart itself and body motion, and a contrast dye material injected. Computer simulation shows that the good reproduction of images can be obtained at a bit rate of 0.78 bits/pixel.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.7
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• pp.566-572
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• 2014

We propose a two-way multi-hop relaying scheme improving the throughput as well as enlarging the coverage for ship-to-ship communications in multi-ship marine networks. The proposed scheme reduces the time slots required for the data exchange by designing data transmission and network coding procedures in a sophisticated way based on two-phase digital network coding. Simulation results show that the proposed two-way multi-hop relaying scheme improves the throughput of the conventional one about 5/3 times.

• Electronics and Telecommunications Trends
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• v.35 no.7
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• pp.23-35
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• 2020

In this paper, we introduce ETRI AI Strategy #3, "Leading Future Technologies of Network, Media, and Content." Its first goal is "to innovate AI service technology to overcome the current limitations of AI technologies." Artificial intelligence (AI) services, such as self-driving cars and robots, are combinations of computing, network, AI algorithms, and other technologies. To develop AI services, we need to develop different types of network, media coding, and content creation technologies. Moreover, AI technologies are adopted in ICT technologies. Self-planning and self-managing networks and automatic content creation technologies using AI are being developed. This paper introduces the two directions of ETRI's ICT technology development plan for AI: ICT for AI and ICT by AI. The area of ICT for AI has only recently begun to develop. ETRI, the ICT leader, hopes to have opportunities for leadership in the second wave of AI services.

• International Journal of CAD/CAM
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• v.3 no.1_2
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• pp.97-109
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• 2003

A large scale polygon models are often used to approximately represent 3D CAD models in Digital Engineering environment such as DMU (Digital Mockups) and network based collaborative design. However, they are not suitable for distribution on the network and for interactive rendering. We introduce a new coding system based on subdivision schemes called S-CODE system. In this system, it is possible to highly compress the model with sufficient accuracy and to view the model efficiently in a level of detail (LOD) fashion. The method is based on subdivision surface fitting by which a subdivision surface and curves which approximate a face of a CAD model are generated. We also apply a subdivision method to analytic surfaces such as conical and cylindrical surfaces. A prototype system is developed and used for evaluation with reasonably complicated data. The results show that the method is useful as a CAD data coding system.

• The Journal of Information Systems
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• v.31 no.3
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• pp.1-18
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• 2022

Purpose The purpose of this study is to analize a psychological and behavioral mechanism for using profile picture management in digital service such as social network service. Profile picture management falls under metadata management and is performed only by those who want it. This means that it, is one of the typical makeup-type digital shadow works (DSWs) which have not been studied yet. Design/methodology/approach This study adopts ground theory method(GTM) as research methodology. GTM, which is one of qualitative methodologies, is for developing theories while most survey based methodologies, which are well adopted in much research for information systems, are for validation of theories. By interviewing ten users, the data are collected and analyzed by open coding, axis coding with paradigm model, and selective coding. Findings In result, 39 codes are found and classified into 29 sub classes and 15 classes. These 15 classes are organized by paradigm model which derives core code of profile picture management as 'voluntary management tasks to experience small pleasures with intermittent attention'. Finally, based on the paradigm model and the core code, the story line, which can explain profile picture management, is suggested.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.192-194
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• 2005

Acceptance of the international standards for video compression, such as H.261, MPEG-1 and MPEG-2, along with the developments in video codec hardware, has created an explosion of application. Among these, the long time quest for long-distance digital video transmission causes an increasing interest in transporting compressed video over networks which are nontraditional for this purpose, including asynchronous transfer mode networks, the Internet, and cellular and wireless channels. Transmission of compression video over packet network is improved for error resilience. And layered video coding techniques improves error resilience. We present a efficient method of scalable video coding for low bandwidth.