The new digital radio system DAB (Digital Audio Broadcasting, nowadays often
called Digital Radio) is a very innovative and universal multimedia broadcast system
which will replace the existing AM and FM audio broadcast services in many parts of
the world in the future. It was developed in the 1990s by the Eureka 147/DAB
project. DAB is very well suited for mobile reception and provides very high robustness
against multipath reception. It allows use of single frequency networks (SFNs)
for high frequency efficiency....
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Effective Radio Resource Management for Multimedia Broadcast/Multicast Services in UMTS Networks
Television has attracted young viewers since broadcasting be-
gan in the 1940s. Concerns about its effects on the cognitive devel-
opment of young children emerged almost immediately and have
been fueled by academic research showing a negative association
between early-childhood television viewing and later academic
1 These ﬁndings have contributed to a belief among
the vast majority of pediatricians that television has “negative
effects on brain development” of children below age ﬁve (Gentile
et al. 2004).
The ﬁrst graph, which shows penetration in 1950, reveals
a clear distinction between counties that had a station in their
DMA and those that did not. The average penetration in DMAs
whose ﬁrst station began broadcasting before 1950 ranges from
8% in the 1949 group to over 35% in the 1941 group, whereas the
average for groups getting television after 1950 never exceeds 1%.
The second graph shows that, by 1960, differences in penetration
across these DMAs had largely disappeared.
For users of image management systems, and especially for the user who
doesn't know what he wants until he sees it, these systems should be
organized in such a way as to support intelligent browsing so that the
user will be satisjed in the shortest amount of time. It is our belief that
intelligent browsing should be mediated by the standard paradigms of
image similarity as well as by an appropriate organization of metadata,
including annotations and self-describing image regions.
Video processing has been a rapidly evolving ﬁeld for telecommunications, computer, and media industries. In particular, for real time video compression applications a growing economical signiﬁcance is expected for the next years. Besides digital TV broadcasting and videophone, services such as multimedia education, teleshopping, or video mail will become audiovisual
It is expected that in many countries digital broadcasting systems will mostly replace current FM radio and television technology in the course of the next one or two decades. The digital media not only offer superior image and audio quality and interesting new types of multimedia data services “on the air,” but also have the potential to employ the scarce resource of broadcast frequencies much more efficiently.
Since the 1990s, digital signals have been increasingly used not only in various industries and engineering equipments
but also in everybody’s daily necessities. Mobile phones, TV receivers, music CDs, multimedia computing, etc, are the
indispensable items in modern life, in which digital formats are taken as a basic form for carrying and storing information.
The major reason for the advancement in the use of digital signals is the big leap forward in the popularization of
microelectronics and computing technology in the past three decades.
Chapter 25 - Multimedia. Recent advances in technology have changed our use of audio and video. In the past, we listened to an audio broadcast through a radio and watched a video program broadcast through a TV. We used the telephone network to interactively communicate with another party. But times have changed. People want to use the Internet not only for text and image communications, but also for audio and video services. In this chapter, we concentrate on applications that use the Internet for audio and video services.