HTTP adaptive steaming (HAS) is becoming ubiquitous as a reliable method of delivering video content over the open Internet to a variety of devices fromBy introducing various network impairments, we were able to demonstrate that video quality gracefully declined until network conditions became too harsh. As a baseline, we compared them with the Microsoft Mediaroom* Internet Protocol television (IPTV) solution currently deployed by service providers. The HD content was encoded at 6.0 Mb/s.The second approach was to create several clips in which exaggerated errors (such as visual artifacts) typical of HAS were introduced on purpose. These were shown to a much wider audience than we could bring into our test labs. Specifically, we used 150 volunteers from the Alcatel-Lucent Youth Lab to offer their subjective assessment of several pieces of content.From these experiments, we conclude that HAS is suitable for delivery of quality video over unmanaged IntroductionHTTP adaptive steaming (HAS) is becoming ubiquitous as a reliable method of streaming video content over unmanaged networks to a sizable number of classes of devices including smartphones, tablets, laptops and desktop personal computers (PCs) connected to small and medium-sized screens. It achieves this by dynamically adjusting the video quality to match the available bandwidth. This paper reports on two approaches to end user subjective testing of response to these changes in quality.The first approach was to invite a panel of viewers into our test lab facility. They were asked to rate high definition (HD) video content displayed by commercially available HTTP adaptive streaming solutions including Microsoft Smooth Streaming, Apple HTTP Live Streaming, and Adobe Dynamic Streaming.

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The paper presents results regarding the mechanical properties of concretes prepared with various amounts of recycled concrete aggregate (RCA). RCA was obtained by the crushing of concrete rubble resulted during the demolition of a block of flats. The concretes with RCA were prepared using three different mixing approaches: one stage mixing (1SM), two stages mixing (2SM) and two stages mixing with polyvinyl acetate addition (2SM PA). Two stages mixing method in the presence of polyvinyl acetate addition, leads to an improvement of the mechanical strengths (compressive and splitting tensile strength due to a better bonding between the binding matrix formed in the new concrete and the old mortar adhered at the surface of RCA grains.

This work presents the performance analysis of ring resonator-based tuneable optical filters, namely the influence of the design parameters such as coupling coefficient (k), coupler loss coefficient (a) and operating temperature (t) on the optical performance of the filter. Computed results have shown that a and k dramatically influences the performance of the add-drop filter, the operating temperature can effectively be used as a mechanism of selecting the desired frequencies within the dynamic range of the filter, and special attention should be paid to the operating temperature range of the filter in order to avoid a decrease of its free spectral range bellow the value of the desired pass bandwidth. Preliminary sensitivity analysis has also revealed that the single ring add-drop filter design is almost insensitive to the relative position of the two optical couplers onto the ring, and therefore very versatile for integration into a photonic chip.