• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.11A
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• pp.1253-1262
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• 2004

The Data Over Cable System Interface Specification (DOCSIS) protocol enables the delivery of Internet Protocol(IP) traffic over Cable TV networks with significantly higher data rates. In this paper, we assessed the performance of the DOCSIS protocol using the OPNET. The simulation can be used to predict the upstream system throughput, mean access delay and channel utilization on varying packet size and transmission stream and wid/without concatenation, and it has shown that maximum system throughput is 4.6 Mbps for channel capacity of 5.12 Mbps and packet size of 1500 bytes. The mean access delay varies depending on the offered load, and it is assumed that the offered load does not exceed the capacity of the channel. Excess offered load causes service starvation according to the assigned priority.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.1038-1044
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• 2009

Interests for User Interface directly influencing on usability are also growing as the competition between DCATV and IPTV come to the surface, according to getting activated Interactive TV market. Therefore, this study has the purpose to understand mental models of users for Interactive TV service & Interface. The methods for this study are as follows. First, as the step considering literature study, we compared differences between DCATV and IPTV and caught up the concepts of DCATV and IPTV among some types of Interactive TV. Second, we examinated and analysed Hello TV, C&M, Broad&TV, MegaTV, myLGtv as the step of analysis for examples for Interactive TV. Third, as the step of researches observing users we analysed usability problems caused by differences of mental models between DCATV and IPTV. As a result, we could find there are some differences for mental model of users in Interface & services between DCATV and IPTV Especially, it was found that users feel confused very much regarding perception of real time broadcasting and VOD. We regards this findings can be used as basic for concept makings of Interactive TV, when TV interface is developed in the future.

• Archives of design research
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• v.18 no.1 s.59
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• pp.39-48
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• 2005

In the age of digital culture, TV broadcasting is exercising more influence as a information and communication medium compared to past. With the appearance of satellite broadcasting service in 2002, the broadcasting environment became a diversified field of local TV, cable TV, satellite, internet, etc. and created the time of multi-media and multi-channel. This ongoing change of broadcasting environment made the passive audience of the past, active image makers and new accepters, participants and users of communications, who know how to choose and use media as the active centerpiece, The active acceptor as the centerpiece of channel selections has become the center of the broadcasting, whereby they pick up and enjoy their favorite TV programs and came to remember the list of their favorite channels and zap them finally. In this point of spotting their favorite channels and improving the degree of recognition for the channels, the development of the noticeable brand for a particular program has made a great contribution. The aim of this study, therefore, is to recognize the factors, which are important in the habits of watching TV and to develop professional brands for TV broadcasting programs. The range of the survey for this study was home news programs and broadcasting stations abroad, which were on air from March to May in 2004. The focus of the survey was universal and professional news programs. Through this study, it was ascertained that, in the case of news, developing a brand for an anchor as well as for a professional brand of TV program could be an important element.