Fast Radio Broadcasting with Advice

International audienceWe study deterministic broadcasting in radio networks in the recently introduced framework of network algorithms with {\em advice}. We concentrate on the problem of trade-offs between the number of bits of information (size of advice) available to nodes and the time in which broadcasting can be accomplished. In particular, we ask what is the minimum number of bits of information that must be available to nodes of the network, in order to broadcast very fast. For networks in which constant time broadcast is possible under complete knowledge of the network we give a tight answer to the above question: $O(n)$ bits of advice are sufficient but $o(n)$ bits are not, in order to achieve constant broadcasting time in all these networks. This is in sharp contrast with geometric radio networks of constant broadcasting time: we show that in these networks a constant number of bits suffices to broadcast in constant time. For arbitrary radio networks we present a broadcasting algorithm whose time is inverse-proportional to the size of advice

Content-Based Video Retrieval in Historical Collections of the German Broadcasting Archive

The German Broadcasting Archive (DRA) maintains the cultural heritage of radio and television broadcasts of the former German Democratic Republic (GDR). The uniqueness and importance of the video material stimulates a large scientific interest in the video content. In this paper, we present an automatic video analysis and retrieval system for searching in historical collections of GDR television recordings. It consists of video analysis algorithms for shot boundary detection, concept classification, person recognition, text recognition and similarity search. The performance of the system is evaluated from a technical and an archival perspective on 2,500 hours of GDR television recordings.Comment: TPDL 2016, Hannover, Germany. Final version is available at Springer via DO

Demanding stories: television coverage of sustainability, climate change and material demand

This paper explores the past, present and future role of broadcasting, above all via the medium of television, in shaping how societies talk, think about and act on climate change and sustainability issues. The paper explores these broad themes via a focus on the important but relatively neglected issue of material demand and opportunities for its reduction. It takes the outputs and decision-making of one of the world’s most influential broadcasters, the BBC, as its primary focus. The paper considers these themes in terms of stories, touching on some of the broader societal frames of understanding into which they can be grouped. Media decision-makers and producers from a range of genres frequently return to the centrality of ‘story’ in the development, commissioning and production of an idea. With reference to specific examples of programming, and drawing on interviews with media practitioners, the paper considers the challenges of generating broadcast stories that can inspire engagement in issues around climate change, and specifically material demand. The concluding section proposes actions and approaches that might help to establish material demand reduction as a prominent way of thinking about climate change and environmental issues more widely. This article is part of the themed issue ‘Material demand reduction’

“Do you really enjoy the modern play?”: Beckett on commercial television

Television was the key popular medium of the second half of the twentieth century in the UK, and Samuel Beckett’s work was consistently aired by BBC, the British non-commercial TV broadcaster that had already featured his work on radio since the mid-1950s. But it is not generally known that his work also appeared on Independent Television, the commercially-funded British television channel set up in 1955 to rival BBC. The commercial ABC TV company made the series The Present Stage for the national ITV network in 1966. In its feature announcing the series, the TV Times listings magazine asked “Do you really enjoy the modern play like Look Back in Anger or Waiting for Godot?" ITV’s first half-hour programme on Waiting for Godot followed DIY expert Barry Bucknell’s demonstration of techniques for laying carpet. The following week’s episode, including extracts from Godot, was preceded by Bucknell’s advice on paving garden patios. This chapter asks what it meant for the ITV commercial channel to make a programme about Beckett’s drama in this context. Moving outwards from the example of The Present Stage, the chapter places Beckett’s drama in a time of dynamic and exciting instability in British culture, when the categories of the popular and the elite were being contested, to argue that Beckett’s work contributed to a cultural revolution

The Legal Needs of Local Media Reform Organizations: Report of a National Survey

This report summarizes a nationwide survey of media reform groups to gauge their needs for pro bono legal assistance. Conclusions are that local media democracy groups need legal help on multiple issues, ranging from municipal broadband to cable franchising to low-power radio

Deterministic Graph Exploration with Advice

We consider the task of graph exploration. An $n$-node graph has unlabeled nodes, and all ports at any node of degree $d$ are arbitrarily numbered $0,\dots, d-1$. A mobile agent has to visit all nodes and stop. The exploration time is the number of edge traversals. We consider the problem of how much knowledge the agent has to have a priori, in order to explore the graph in a given time, using a deterministic algorithm. This a priori information (advice) is provided to the agent by an oracle, in the form of a binary string, whose length is called the size of advice. We consider two types of oracles. The instance oracle knows the entire instance of the exploration problem, i.e., the port-numbered map of the graph and the starting node of the agent in this map. The map oracle knows the port-numbered map of the graph but does not know the starting node of the agent. We first consider exploration in polynomial time, and determine the exact minimum size of advice to achieve it. This size is $\log\log\log n -\Theta(1)$, for both types of oracles. When advice is large, there are two natural time thresholds: $\Theta(n^2)$ for a map oracle, and $\Theta(n)$ for an instance oracle, that can be achieved with sufficiently large advice. We show that, with a map oracle, time $\Theta(n^2)$ cannot be improved in general, regardless of the size of advice. We also show that the smallest size of advice to achieve this time is larger than $n^\delta$, for any $\delta <1/3$. For an instance oracle, advice of size $O(n\log n)$ is enough to achieve time $O(n)$. We show that, with any advice of size $o(n\log n)$, the time of exploration must be at least $n^\epsilon$, for any $\epsilon <2$, and with any advice of size $O(n)$, the time must be $\Omega(n^2)$. We also investigate minimum advice sufficient for fast exploration of hamiltonian graphs

Science, TV and education: active, not passive learning at a distance?

Talk to scientists, broadcasters, educationalists or those working for the public understanding of science and you will get, almost certainly, a view that science has a declining presence in the output of major broadcasters. This chapter considers the potential – and limitation – of TV for science education and presents some data on successful science broadcast projects