• Journal of the Korea Society of Computer and Information
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• v.18 no.11
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• pp.107-113
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• 2013

Mobile mobility and data reliability should be guaranteed as well as amounts of data services are essential in the era of smart media. In order to improve the reliability of high-speed data, strong channel coding and modulation techniques are required. In this paper, the structure of Turbo TCM decoder, applying high-order modulation techniques and the DPSAM method which improves performances in time-selective fading channels in the case of burst errors are suggested through the optimal decoding method and iteration decoding so as to improve bandwidth efficiency in Turbo Codes with excellent encoding gain. The proposed method in comparison with the existing method is that 3dB is superior in case that BER is $10^{-2}$ and the number of iterations is 3. In addition, the function is improved at approximately 6dB in case that BER is $10^{-3}$ and the number of iterations is 7. The proposed method requires additional bandwidth; however, the bandwidth loss can be overcome through Turbo TCM technology on the additional bit rate from the bandwidth loss.

• Asia pacific journal of information systems
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• v.17 no.4
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• pp.165-186
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• 2007

With the advent of a wide variety of Internet shopping malls, consumers can choose a best appealing shopping mall from among the Bricks-and-Clicks and Pure-Player malls. Pure-Players launched their operation grandiosely with the early stage of Internet use in 1995. However, after the burst of Dot-com company bubbles in 1997, Pure-Players introduce various types of business models to meet potential needs of consumers. While Pure-Players suffer skeptical views from market analysts as well as consumers, traditional offline companies learned important lessons from Dot-com companies collapse phenomena, and expanded their business channels into online in the name of Bricks-and-Clicks. Nowadays, Bricks-and-Clicks successfully establish in the market as one of reliable business partners among consumers. Therefore, it is no surprise that recent competitions between Bricks-and Clicks and Pure-Players become fiercer than ever to attract potential customers to their websites. In this situation, consumers can choose a shopping mall to their best satisfaction. Consumers can enjoy both offline and online options for shopping because Bricks-and Clicks provide both offline and online channels to consumers, which is compared with Pure-Players offering only online channel. Offline channel is unique in providing consumers with chances to touch and feel target products and services. Meanwhile, online channel is considered very viable and convenient shopping options for consumers. In this respect, it is easily assumed that consumers will show different online shopping behavior when they have to choose either Bricks-and-Clicks mall or Pure-Player mall for the sake of shopping. Remaining research issue in this case is how much consumers' schema would influence online shopping behavior between Bricks-and-Clicks and Pure-Players. Basically, schema is a framework for synthetic information recognition that individual consumers have and is very characteristic in that it focuses not on fragmentary facts but on the combination of various causes affecting results. Consumers' schema is closely represented by trust, structural assurance, and perceived relative advantage towards a specific type of shopping mall. In literature, there exist a lot of studies comparing Bricks-and-Clicks and Pure-Players. However, there is no study to pursue the analysis of consumer behaviors comparing Bricks-and Clicks and Pure-Players from the schema perspective. Therefore, this study aims to investigate this research gap. Empirical analysis is adopted by garnering valid questionnaires from 514 Internet shopping mall users. 237 were mainly using Bricks-and-Clicks for shopping, while 277 were found to visit Pure-Players for shopping. PLS was applied to analyze the survey data to verify the proposed research hypotheses. Findings from the empirical test results are as follows. First, consumers perceive more trust and relative advantage in Pure-Players, comparing with Bricks-and-Clicks. This result is against widely-accepted perception that Bricks-and-Clicks would be perceived by consumers as more trustworthy and relatively advantageous because they have offline reputation and stores. Therefore, it becomes more obvious that Internet is becoming daily necessaries, and consumers increasingly feel very comfortable in using the Internet for their own personal purposes. Second, consumers have firm faith in transaction safety, regardless Bricks-and-Clicks and Pure-Players. This seems due to the fact that most of shopping malls showing dubious transaction safety have no place in the market. In a nutshell, empirical results tell us that Pure-Players will grow very much in the future, to the extent that consumers perceive no difference in comparison with Bricks-and-Clicks. Besides, consumers' schema accumulated through trust and perceived relative advantage plays crucial role in determining consumer behavior.

• The KIPS Transactions:PartB
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• v.10B no.2
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• pp.143-150
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• 2003

Error concealment plays an important role in combating transmission errors. Methods of error concealment which produce better quality are generally of higher complexity, thus making some of the more sophisticated algorithms is not suitable for real-time applications. In this paper, we develop temporal and spatial error resilient video encoding and data hiding approach to facilitate the error concealment at the decoder. Block interleaving scheme is introduced to isolate erroneous blocks caused by packet losses for spatial area of error resilience. For temporal area of error resilience, data hiding is applied to the transmission of parity bits to protect motion vectors. To do error concealment quickly, a set of edge features extracted from a block is embedded imperceptibly using data hiding into the host media and transmitted to decoder. If some part of the media data is damaged during transmission, the embedded features are used for concealment of lost data at decoder. This method decreases a complexity of error concealment by reducing the estimation process of lost data from neighbor blocks. The proposed data hiding method of parity bits and block features is not influence much to the complexity of standard encoder. Experimental results show that proposed method conceals properly and effectively burst errors occurred on transmission channel like Internet.