Cooperative Buffering Schemes for Time-Shifted Live Streaming of Distributed Appliances

Distributed appliances connected to the Internet have provided various multimedia services. In particular, networked Personal Video Recorders (PVRs) can store broadcast TV programs in their storage devices or receive them from central servers, enabling people to watch the programs they want at any desired time. However, the conventional CDNs capable of supporting a large number of concurrent users have limitations in scalability because more servers are required in proportion to the increased users. To address this problem, we have developed a time-shifted live streaming system over P2P networks so that PVRs can share TV programs with each other. We propose cooperative buffering schemes to provide the streaming services for time-shifted periods even when the number of PVRs playing back at the periods is not sufficient; we do so by utilizing the idle resources of the PVRs playing at the live broadcast time. To determine which chunks to be buffered, they consider the degree of deficiency and proximity and the ratio of playback requests to chunk copies. Through extensive simulations, we show that our proposed buffering schemes can significantly extend the time-shifting hours and compare the performance of two buffering schemes in terms of playback continuity and startup delay.

„Atgimimo banga“ Challenge to Soviet Mass media: Reform Movement of Lithuania (Sąjūdis) Telecast as „Open Protest Field“ in Time of Political Changes (1988 June– 1990 March)

During the Soviet occupation, the whole Lithuanian SSR media was regarded as one of the key propaganda tools based on pure ideological content and socialist-communist messages. In such a media setting television played an essential role; together with radio (as in Moscow’s example) the latter felt under control of a committee ruled by the Council of Ministers (CM), Central Committee (CC) and Moscow patrons itself. But this situation was about to change when Sąjūdis (Reform Movement of Lithuania) came to public and tried to established its right to uncensored broadcast time via television for its own dissemination of information, which sometimes had a strong political message and was not in favour of ruling regime and party. Sąjūdis had a purpose which was totally new during Lithuanian SSR times since the start of television broadcasts in 1957 – it was uncensored broadcasting time. Based on archive sources, memoirs and press articles, this research focuses on the telecast “Atgimimo banga“ as one of the essential informational channels for Sąjūdis. This article tries to disclose its history, influence and conflicts between Sąjūdis and ruling regime, which tried to control and censor telecast’s content. Eventually, the sporadic telecast’s format had another effect: when in 1989 Sąjūdis became important part of the Lithuanian SSR political system, telecast’s popularity came to decline. One of the most popular perestroika time TV programs had some unfulfilled expectations, and, during the time, it made it as one of the most unpopular. The chronological boundaries of this research start at June of 1988, when Sąjūdis was created, and ends in March of 1990, when Lithuania declared its independence from Soviet Union.

Pink Floyd’s Time: an aural metanarrative exploring time through form, lyric, and musical arrangement

The inability of language to capture the essence of time is a crisis that has been expressed by philosophers starting from St. Augustine to Paul Ricoeur. Appearing on their seminal album, Dark Side of the Moon, Pink Floyd’s Time is a profound artistic attempt which transcends this language barrier by using music to bring the listeners to a more direct confrontation with time; doing so by juxtaposing time as calibrated and as experienced through the music and the lyrics, and by making the reader experience time-based affects such as impatience, expectation, monotony, and such. As a direct function of song, time is experienced as musical time in the song, thereby ensuring that the listener’s confrontation with time is immersive, with lyrics that describe the nature of experienced and calibrated time working synchronously with the music to complete the image. In the context of its release in 1974, the 6:52 minute song was in engagement with the concept of time as well, in that it was among the pioneering ones which redefined radio broadcast time beyond the standard 3 minutes afforded to popular music tracks, with the commercially preferred listener span in mind. The matter of time thus becomes a multi-layered formal engagement in the song, at the level of lyric, recording, music and listening, thereby making possible an image of time that is polished and rounded. These aural, lyrical and production-based concepts will be addressed and expanded upon to show how Pink Floyd’s Time functions as a metanarrative in how it uses and invokes the elements of time to talk about time.

Approximation Algorithm for the Broadcast Time in k-Path Graph

Broadcasting is an information dissemination problem in a connected network in which one node, called the originator, must distribute a message to all other nodes by placing a series of calls along the communication lines of the network. In every unit of time, the informed nodes aid the originator in distributing the message. Finding the broadcast time of any vertex in an arbitrary graph is NP-complete. The polynomial time solvability is shown only for certain graphs like trees, unicyclic graphs, tree of cycles, necklace graphs, fully connected trees and tree of cliques. In this paper we study the broadcast problem in k-path graphs. For any originator of the k-path graph we present a (4 – ϵ)-approximation algorithm in the worst case. The algorithm gives a better approximation ratio for some large classes of k-path graphs. Moreover, our algorithm generates the optimal broadcast time for some cases.