1,156,983 research outputs found
Optical network technologies for future digital cinema
Digital technology has transformed the information flow and support infrastructure for numerous application domains, such as cellular communications. Cinematography, traditionally, a film based medium, has embraced digital technology leading to innovative transformations in its work flow. Digital cinema supports transmission of high resolution content enabled by the latest advancements in optical communications and video compression. In this paper we provide a survey of the optical network technologies for supporting this bandwidth intensive traffic class. We also highlight the significance and benefits of the state of the art in optical technologies that support the digital cinema work flow
An experimental course on digital communications
In this paper a laboratory course on digital communications is presented. This course has been designed for medium degree professionals in the telecommunications field, and it is based on training equipment developed to change the usual theoretical classrooms for laboratory seminars.Peer ReviewedPostprint (published version
A flight investigation of simulated data link communications during single-pilot IFR flight
A Flight Data Console (FDC) was developed to allow simulation of a digital communications link to replace the current voice communication system used in air traffic control (ATC). The voice system requires manipulation of radio equipment, read-back of clearances, and mental storage of critical information items, all contributing to high workload, particularly during single-pilot operations. This was an inflight study to determine how a digital communications system might reduce cockpit workload, improve flight proficiency, and be accepted by general aviation pilots. Results show that instrument flight, including approach and landing, can be accomplished quite effectively using a digital data link system for ATC communications. All pilots expressed a need for a back-up voice channel. When included, this channel was used sparingly and principally to confirm any item of information about which there might be uncertainty
Overview of timing/synchronization for digital communications
Systems in general, and switched systems in particular, are explained. It pointed out some of the criteria that greatly influence timing/synchronization subsystem design for a military communications network but have little or no significance for civil systems. Timing techniques were evaluated in terms of fundamental features. Different combinations of these features covered most possibilities from which a synchronous timing system could be chosen
A generalized transmultiplexer and its application to mobile satellite communications
A generalization of digital transmultiplexer technology is presented. The proposed method can realize transmultiplexer (TMUX) and transdemultiplexer (TDUX) filter banks whose element filters have bandwidths greater than the channel spacing frequency. This feature is useful in many communications applications. As an example, a satellite switched (SS) Frequency Division Multiple Access (FDMA) system is proposed for spot beam satellite communications, particularly for mobile satellite communications
A flight investigation of simulated data-link communications during single-pilot IFR flight. Volume 2: Flight evaluations
Key problems in single pilot instrument flight operations are in the management of flight data and the processing of cockpit information during conditions of heavy workload. A flight data console was developed to allow simulation of a digital data link to replace the current voice communications stem used in air traffic control. This is a human factors evaluation of a data link communications system to determine how such a system might reduce cockpit workload, improve flight proficiency, and be accepted by general aviation pilots. The need for a voice channel as backup to a digital link is examined. The evaluations cover both airport terminal area operations and full mission instrument flight. Results show that general aviation pilots operate well with a digital data link communications system. The findings indicate that a data link system for pilot/ATC communications, with a backup voice channel, is well accepted by general aviation pilots and is considered to be safer, more efficient, and result in less workload than the current voice system
A survey on cyber security for smart grid communications
A smart grid is a new form of electricity network with high fidelity power-flow control, self-healing, and energy reliability and energy security using digital communications and control technology. To upgrade an existing power grid into a smart grid, it requires significant dependence on intelligent and secure communication infrastructures. It requires security frameworks for distributed communications, pervasive computing and sensing technologies in smart grid. However, as many of the communication technologies currently recommended to use by a smart grid is vulnerable in cyber security, it could lead to unreliable system operations, causing unnecessary expenditure, even consequential disaster to both utilities and consumers. In this paper, we summarize the cyber security requirements and the possible vulnerabilities in smart grid communications and survey the current solutions on cyber security for smart grid communications. © 2012 IEEE
Circuit maintains digital decision threshold at preset level
Optimum decision-level circuit maintains the decision threshold at any preselected percentage of the input-signal amplitude. Communications equipment involving recognition of transmitted digital information can benefit from this circuit
Preparing millennials as digital citizens and socially and environmentally responsible business professionals in a socially irresponsible climate
As of 2015, a millennial born in the 1990's became the largest population in
the workplace and are still growing. Studies indicate that a millennial is tech
savvy but lag in the exercise of digital responsibility. In addition, they are
passive towards environmental sustainability and fail to grasp the importance
of social responsibility. This paper provides a review of such findings
relating to business communications educators in their classrooms. The
literature should enable the development of a millennial as an excellent global
citizen through business communications curricula that emphasizes digital
citizenship, environmental sustainability and social responsibility. The
impetus for this work is to provide guidance in the development of courses and
teaching strategies customized to the development of each millennial as a
digital, environmental and socially responsible global citizen
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