• Journal of Broadcast Engineering
• /
• v.10 no.3
• /
• pp.328-338
• /
• 2005

Technology for compressing low-bitrate multichannel audio coding is being standardized owing to the increasing need of consumer for multichannel audio contents. In this paper we propose the sound source location cue coding (SSLCC) for extremely compressing multichannel audio to be suitable at the narrow bandwidth transmission environment. To improve the compression capability of the conventional binaural cue coding(BCC), the SSLCC adopts the virtual source location information (VSLI) as a spatial cue parameter, a symmetric uniform quantizer, and Huffman coder. The objective and subjective assessment results show that the SSLCC provides lower bitrate and better audio quality than conventional BCC method.

• Journal of Korea Multimedia Society
• /
• v.6 no.7
• /
• pp.1219-1230
• /
• 2003

We analyze an integrated voice/data CDMA system, where the whole channels are divided into voice prioritized channels and voice non-prioritized channels. For real-time voice service, a preemptivc priority is granted in the voice prioritized channels. And, for delay-tolerant data service, the employment of buffer is considered. On the other hand, the transmission permission probability in best-effort packet-data service is controlled by estimating the residual capacity available for users. We build a 2-dimensional markov chain about prioritized-voice and stream-data services and accomplish numerical analysis in combination with packet-data traffic based on residual capacity equation.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.4A
• /
• pp.330-335
• /
• 2007

This paper proposes a multichannel random access channel allocation scheme for multihop cellular networks to guarantee the stable throughput of a random access. The fundamental contribution is a mathematical formula for an optimal partition ratio of shared random access channels between a base station and a relay station. In addition, the proposed scheme controls the retransmission probability of random access packets under heavy load condition. Simulation results show that the proposed scheme can guarantee the required random access channel utilization and packet transmission delay even if the a random access packet arrival rate is higher than 0.1.

• Proceedings of the Korean Information Science Society Conference
• /
• 2012.06b
• /
• pp.474-476
• /
• 2012

본 논문에서는 드라마 동영상의 의미 분절화(Semantic segmentation)를 위한 멀티 채널 기반 비모수적 베이지만 방법론을 소개한다. 기존 방법론은 매우 한정적인 특징만을 이용하여 분절화를 시도하거나 이미지 채널이나 오디오 채널과 같은 단일 채널에서만 유효한 방법론을 이용하여 데이터 분석을 시도하였기에, TV 드라마와 같이 예측할 수 없는 변화를 보여주는 스트림 데이터에 적용하기에는 어려움이 많았다. 이와 같은 단점을 극복하기 위해 우리는 주어진 동영상을 단일 모달리티의 채널로 분할한 후 각 채널 별로 분절화를 시도하고 각 채널의 분절 결과를 동적으로 결합하여 주어진 동영상에서의 의미 분절화를 근사하는 방법을 개발하였다. 제안 방법은 실제 TV 동영상의 의미 분절화에 적용되었으며 인간 평가자에 의한 의미 변화 구간과의 비교를 통해 그 성능을 확인하였다.

• Journal of Korea Multimedia Society
• /
• v.5 no.6
• /
• pp.704-711
• /
• 2002

Multimedia communication systems are characterized by supporting three different typer of services such as circuit switched services, and packet switched real Lime and non real time services. The wireless channels in a cell ate allocated by calls of these different service classes and the different service requirements have to be met. SRN is an extension of stochastic Petri nets and provides compact Modeling facilities for system analysis. To get the performance index, appropriate reward rates are assigned to its SRN. In this paper, we present a SRN model for performance analysis of channel allocation of multimedia mobile communication systems. The key contribution of this paper constitutes the Petri nets modeling techniques instead of complicate numerical analysis of Markov chains and easy way of performance analysis for channel allocations under SRN rewards concepts.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.30 no.5A
• /
• pp.417-425
• /
• 2005

KOINONIA is high-rate Wireless Personal Area Network (WPAN) technology, and is developed for multimedia traffic transmission in personal area. A KOINONIA piconet is a collection of one or more associated slaves under a single master. Efficient scheduling of a master for the traffic of slaves is essential to use channel effectively and to guarantee QoS of multimedia traffic. We propose a new scheduling algorithm to allocate channel time at desired intervals regardless of superframe length, and a Connection Admission Control(CAC) algorithm to regulate the number of traffics in a piconet. Our proposed algorithms have been shown to save channel time and to meet QoS requirements compared to the conventional weighted round-robin algorithm.

• Journal of Broadcast Engineering
• /
• v.18 no.3
• /
• pp.435-444
• /
• 2013

ATSC terrestrial DTV system can support high data rates for HDTV(High Definition Television) service, but it suffers from significant performance degradation caused by multipath fading. Thus, it is necessary to analyze multipath fading effects in order to enhance the DTV reception performance. Generally, DTV channel profile can be obtained by auto-correlation between reference pseudo random signal and received DTV signal. However, in the ATSC terrestrial DTV system, the estimation performance of DTV channel profile may be decreased due to the VSB modulation features. In this paper, improved DTV channel profile measurement technique is analyzed and proposed.

• Journal of KIISE:Computer Systems and Theory
• /
• v.30 no.5_6
• /
• pp.223-231
• /
• 2003

Video-on-Demand (VOD) service needs high resource consumption because of high bandwidth and long playback duration which are characteristics of multimedia. Various techniques such as Patching and Channel-Reserving Patching have been proposed to reduce the demand on the network-I/O bandwidth. Patching allows new clients to join an existing multicast for realization of true VOD, and Channel-Reserving Patching reserves the part of total channel capacity of video server in order to serve the requests for popular videos on which requests of users concentrate. To improve the performance of Channel-Reserving Patching, we propose the method that determines the reserved channel capacity of video server for the popular videos in this paper. The performance of our method is evaluated in terms of average servile latency, defection ratio and fairness through simulation, and is compared with those of Patching and another Channel-Reserving Patching.

• The Journal of the Korea Contents Association
• /
• v.20 no.6
• /
• pp.279-292
• /
• 2020

The purpose of this study is to suggest what the effect of channel brand equity is in the environment of multi-platform and to raise how channel brand equity is important by investigating how terrestrial TV's channel brand equity influences viewers' choice and use of the terrestrial TV contents on the multi-platform. The findings showed that the terrestrial TV's channel brand equity partially had a significant effect on the degree of use of Terrestrial TV contents on multi-platforms, but it did not on the diversity of media for viewing the terrestrial TV contents. In addition, it partially had an influence on the use of platform and service for viewing terrestrial TV contents by type. Finally, it also partially had impacts on the diversity of genre and the genre use by type. The findings suggest that the channel brand equity can have effects on the viewers' choice and use of broadcasting contents on the multi-platforms, and thus this study provides significant insights on what strategies are required for the competitiveness of broadcasting channels.

• Journal of Korea Multimedia Society
• /
• v.7 no.3
• /
• pp.357-367
• /
• 2004

In VOD systems the number of channels available to a video server is limited since the number of channels, the video server can support, is determined by the communication bandwidth of the video server. Multicast techniques such as batching, patching and batch-patching have been proposed to reduce I/O demand on the video server by sharing multicast data. In this paper, we propose a channel reservation batch-patching technique that first applies the batching technique to hot video requests and then applies the patching technique to the batches of the hot video requests. And the proposed technique reserves a part of the channel capacity of the video server for many hot video requests, so that the hot video requests can be served without defection. The performance of the proposed technique is compared with those of Patching and Batch-Patching techniques in terms of average service latency, defection rate, fairness and frame reduction rate by simulations.