8,795 research outputs found
The 30/20 GHz fixed communications systems service demand assessment. Volume 2: Main report
A forecast of demand for telecommunications services through the year 2000 is presented with particular reference to demand for satellite communications. Estimates of demand are provided for voice, video, and data services and for various subcategories of these services. The results are converted to a common digital measure in terms of terabits per year and aggregated to obtain total demand projections
A Proximity based Retransmission Scheme for Power Line Ad-hoc LAN
Power line as an alternative for data transmission is being explored, and
also being used to a certain extent. But from the data transfer point of view,
power line, as a channel is highly dynamic and hence not quite suitable. To
convert the office or home wiring system to a Local Area Network (LAN),
adaptive changes are to be made to the existing protocols. In this paper, a
slotted transmission scheme is suggested, in which usable timeslots are found
out by physically sensing the media. Common usable timeslots for the
sender-receiver pair are used for communication. But these will not ensure safe
packet delivery since packets may be corrupted on the way during propagation
from sender to receiver. Therefore, we also suggest a proximity based
retransmission scheme where each machine in the LAN, buffers good packet and
machines close to the receiver retransmit on receiving a NACK.Comment: Already published in IJDP
40 Gbps Access for Metro networks: Implications in terms of Sustainability and Innovation from an LCA Perspective
In this work, the implications of new technologies, more specifically the new
optical FTTH technologies, are studied both from the functional and
non-functional perspectives. In particular, some direct impacts are listed in
the form of abandoning non-functional technologies, such as micro-registration,
which would be implicitly required for having a functioning operation before
arrival the new high-bandwidth access technologies. It is shown that such
abandonment of non-functional best practices, which are mainly at the
management level of ICT, immediately results in additional consumption and
environmental footprint, and also there is a chance that some other new
innovations might be 'missed.' Therefore, unconstrained deployment of these
access technologies is not aligned with a possible sustainable ICT picture,
except if they are regulated. An approach to pricing the best practices,
including both functional and non-functional technologies, is proposed in order
to develop a regulation and policy framework for a sustainable broadband
access.Comment: 10 pages, 6 Tables, 1 Figure. Accepted to be presented at the
ICT4S'15 Conferenc
How Would You Like Your Television: With or Without Borders and With or Without Culture--a New Approach to Media Regulation in the European Union
This Essay analyzes the effectiveness of television broadcasting regulations as a means to effectuate the promotion and protection of a pan-European culture, namely, television broadcasting regulations. First, in Part I, this Essay considers the broader background developments in the audio-visual sector that led to the passing of the Directive. Part II looks at the advantages and disadvantages of the most controversial aspect of the Directive, namely, the quota provisions. Part III critiques the Directive\u27s effectiveness in realizing its dual goals of both protecting and promoting a pan-European culture. Finally, Part IV compares the goals enunciated in the Federal Communications Act ( FCC Act ) with those enunciated in the Directive. Both sets of goals reflect similar concerns and interests, although the United States takes a much broader approach in realizing its goals. This Essay concludes that the Community should, like the United States, take a more expansive approach to its audio-visual policy, similar to the approach reflected in the FCC Act, in order to strengthen and effectuate a more solid and unified European broadcast regulatory scheme that both protects and promotes a European culture
Parents, Television and Cultural Change
This paper develops a model of cultural transmission where television plays a central role for socialization. Parents split their free time between educating their children which is costly and watching TV which though entertaining might socialize the children to the wrong trait. The free to air television industry maximizes advertisement revenue. We show that TV watching is increasing in cultural coverage, cost of education, TV's entertainment value and decreasing in the perceived cultural distance between the two traits. A monopolistic television industry captures all TV watching by both groups if the perceived cultural distance between groups is small relative to the TV's entertainment value. Otherwise, more coverage will be given to the most profitable group where profitability increases in group size, advertisement sensitivity and perceived cultural distance. This leads to two possible steady states where one group is larger but both groups survive in the long run. Competition in the media industry might lead to cultural extinction but only if one group is very insensitive to advertisement and not radical enough not to watch TV. We briefly discuss the existing evidence for the empirical predictions of the model.television, socialization, cultural trait dynamics, media coverage.
Applications of satellite technology to broadband ISDN networks
Two satellite architectures for delivering broadband integrated services digital network (B-ISDN) service are evaluated. The first is assumed integral to an existing terrestrial network, and provides complementary services such as interconnects to remote nodes as well as high-rate multicast and broadcast service. The interconnects are at a 155 Mbs rate and are shown as being met with a nonregenerative multibeam satellite having 10-1.5 degree spots. The second satellite architecture focuses on providing private B-ISDN networks as well as acting as a gateway to the public network. This is conceived as being provided by a regenerative multibeam satellite with on-board ATM (asynchronous transfer mode) processing payload. With up to 800 Mbs offered, higher satellite EIRP is required. This is accomplished with 12-0.4 degree hopping beams, covering a total of 110 dwell positions. It is estimated the space segment capital cost for architecture one would be about 250M. The net user cost is given for a variety of scenarios, but the cost for 155 Mbs services is shown to be about $15-22/minute for 25 percent system utilization
- …