• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.12B
• /
• pp.1124-1134
• /
• 2003

The recent intensification of competition in the LM market has become a major issue. In this research effort, a study is made to determine the expected social benefits that can be realized from the increase of competition in the LM market through CPS. Results from this study show that consumer benefits up to 144.8 billion won can be created through the boost in competition from CPS. However, a reduction of 207.9-438.7 billion won in revenues is expected for service providers. Depending on the existing service providers, revenues may fall by at least 264.4 billion won and up to 486.2 billion won. For newcomers to the market 30.2-89.1 billion won will be created.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.10a
• /
• pp.27-30
• /
• 2003

The introduction of reseller In Australian Fixed Telecommunication Market resulted in the reduction of Telstra's local call market share by 13 percent and average fall rate was reduced. Thus, Telstra increased basic rate at 14.5 percent to compensate loss revenue in the local call market. With the deployment of carrier pre-selection of long distance and international calls, it reduced long distance rate at 23.5 percent and international tall rate at 53 percent, and increased the Churn rate. Therefore, the deployment of service-based competition brought efficient results for long distance and international call market. However, LM market created 13.4 percent reduction in call rates, complications in charge system, technical barriers and the preference of one-bill by customers.

• The Journal of the Acoustical Society of Korea
• /
• v.23 no.1
• /
• pp.54-60
• /
• 2004

In order to mitigate the problems in storage space and network bandwidth for the full CD quality audio, current digital audio is always restricted by sampling rate and bandwidth. This restriction normally results in low sample rate audio or calls for the data compression scheme such as MP3. However, they can only reproduce a lower frequency range than a regular CD quality because of the Nyquist sampling theory. Consequently they lose rich spatial information embedded in high frequency. The propose of this paper is to propose efficient high frequency enhancement of low sample rate audio using n adaptive filtering and DWT analysis and synthesis. The proposed algorithm uses the LMS adaptive algorithm to estimate the missing high frequency contents in DWT domain and it then reconstructs the spectrally enhanced audio by using the DWT synthesis procedure. Several experiments with real speech and audio are performed and compared with other algorithm. From the experimental results of spectrogram and sonic test, we confirm that the proposed algorithm outperforms the other algorithm and reasonably works well for the most of audio cases.