On the impact of video stalling and video quality in the case of camera switching during adaptive streaming of sports content

The widespread usage of second screens, in combination with mobile video streaming technologies like HTTP Adaptive Streaming (HAS), enable new means for taking end-users' Quality of Experience (QoE) to the next level. For sports events, these technological evolutions can, for example, enhance the overall engagement of remote fans or give them more control over the content. In this paper, we consider the case of adaptively streaming multi-camera sports content to tablet devices, enabling the end-user to dynamically switch cameras. Our goal is to subjectively evaluate the trade-off between video stalling duration (as a result of requesting another camera feed) and initial video quality of the new feed. Our results show that short video stallings do not significantly influence overall quality ratings, that quality perception is highly influenced by the video quality at the moment of camera switching and that large quality fluctuations should be avoided

Nutrition Strategies for Triathlon

Contemporary sports nutrition guidelines recommend that each athlete develop a personalised, periodised and practical approach to eating that allows him or her to train hard, recover and adapt optimally, stay free of illness and injury and compete at their best at peak races. Competitive triathletes undertake a heavy training programme to prepare for three different sports while undertaking races varying in duration from 20 min to 10 h. The everyday diet should be adequate in energy availability, provide CHO in varying amounts and timing around workouts according to the benefits of training with low or high CHO availability and spread high-quality protein over the day to maximise the adaptive response to each session. Race nutrition requires a targeted and well-practised plan that maintains fuel and hydration goals over the duration of the specific event, according to the opportunities provided by the race and other challenges, such as a hot environment. Supplements and sports foods can make a small contribution to a sports nutrition plan, when medical supplements are used under supervision to prevent/treat nutrient deficiencies (e.g. iron or vitamin D) or when sports foods provide a convenient source of nutrients when it is impractical to eat whole foods. Finally, a few evidence-based performance supplements may contribute to optimal race performance when used according to best practice protocols to suit the triathlete’s goals and individual responsiveness

Demand Layering for Real-Time DNN Inference with Minimized Memory Usage

When executing a deep neural network (DNN), its model parameters are loaded into GPU memory before execution, incurring a significant GPU memory burden. There are studies that reduce GPU memory usage by exploiting CPU memory as a swap device. However, this approach is not applicable in most embedded systems with integrated GPUs where CPU and GPU share a common memory. In this regard, we present Demand Layering, which employs a fast solid-state drive (SSD) as a co-running partner of a GPU and exploits the layer-by-layer execution of DNNs. In our approach, a DNN is loaded and executed in a layer-by-layer manner, minimizing the memory usage to the order of a single layer. Also, we developed a pipeline architecture that hides most additional delays caused by the interleaved parameter loadings alongside layer executions. Our implementation shows a 96.5% memory reduction with just 14.8% delay overhead on average for representative DNNs. Furthermore, by exploiting the memory-delay tradeoff, near-zero delay overhead (under 1 ms) can be achieved with a slightly increased memory usage (still an 88.4% reduction), showing the great potential of Demand Layering.Comment: 14 pages, 16 figures. Accepted to the 43rd IEEE Real-Time Systems Symposium (RTSS), 202

Quantifying the influence of rebuffering interruptions on the user's quality of experience during mobile video watching

Entertainment and multimedia are the key functionalities in emerging mobile markets. The ability to understand and quantify the quality of experience (QoE, i.e., the users' subjective perception of the "overall acceptability of an application or service"), will play a major role in the success of these mobile services. This study explores the thresholds at which the technical quality of a mobile video service becomes unacceptable for users. A subjective experiment drawing on the logging of technical parameters combined with subjective evaluations by a user panel resulted in a model for quantifying the acceptability of video interruptions. The results of this analysis provide insights into the QoE and (un)acceptability regarding video interruptions for different network conditions and video parameters. The conclusions of this paper can be used as a guideline for service design and network dimensioning

Hydrothermal hydrolysis of starch with CO2 and detoxification of the hydrolysates with activated carbon for bio-hydrogen fermentation.

The imminent use of hydrogen as an energy vector establishes the need for sustainable production technologies based on renewable resources. Starch is an abundant renewable resource suitable for bio-hydrogen generation. It was hypothesised that starch hydrolysates from a large (250 mL) hydrothermal reactor could support bioH2 fermentation without inhibition by toxic byproducts.\ud \ud Starch was hydrolysed at high concentrations (40 200 g.L-1) in hot compressed water (HCW) with CO2 at 30 bar in a 250 mL reactor, the largest so far for polysaccharide hydrolysis, at 180 235 °C, 15 min. Hydrolysates were detoxified with activated carbon (AC) and tested in biohydrogen fermentations. The maximum yield of glucose was 548 g.kg starch 1 carbon at 200 °C. 5 hydroxymethyl furfural, the main fermentation inhibitor, was removed by AC to support 70% more hydrogen production than the untreated hydrolysates. The potential utilization of starch hydrolysates from HCW treatment for upscaled fermentations is promising

Optimal Universal Schedules for Discrete Broadcast

We study broadcast systems that distribute a series of data updates to a large number of passive clients. The updates are sent over a broadcast channel in the form of discrete packets. We assume that clients periodically access the channel to obtain the most recent update. Such scenarios arise in many practical applications, such as distribution of traffic information and market updates to mobile wireless devices

Lowering Sperm Dose Rates in Frozen Semen for Bovine Artificial Breeding

The New Zealand Dairy industry relies on artificial breeding to produce high genetic merit replacement stock. Proven bull semen is extended and preserved as either ambient temperature product or as frozen doses. High fertility is essential to maintain synchronicity of lactation with the spring surge of grass growth. To improve efficiency in the utilization of the very best bulls producers try to lower sperm dose rates without compromising fertility. Livestock Improvement Corporation's (LIC) Long Last Liquid ™ (LLL) is most commonly used during the peak season and is their most important product. However, shortfalls and specifically targeted matings are met with frozen semen. Lowering sperm dose rates in both liquid and frozen semen maximises the usage of elite sires increasing genetic gain, lowering overheads and garnering premium prices for the semen producer. A product for improving frozen semen technology was developed whereby a discrete quantity of pretreated semen was placed alongside a beneficial post-thawing redilution medium in a standard semen straw. This emulated a larger-scale process developed to freeze semen in times of low demand and redilution into the LLL form for use as an ambient temperature product. This rediluted product has been proved to enhance semen survival and to allow fertility to be maintained at sperm dose rates lower than the widely accepted standard for frozen semen. The physical packaging of the semen into the industry standard single dose straw in a configuration that separated incompatible components was novel. This configuration was essential to prevent damage to the sperm during the freezing process from low solubility components in the post-thaw redilution medium. Separation between the semen and diluent within the straw was achieved by the introduction of a gas partition or air bubble between the two liquids. A large-scale field trial showed that the new product could produce savings of up to 25% of the sperm needed for a semen dose to achieve equivalent fertility. Furthermore, the production cost per dose was lowered in comparison to the standard semen processing system used at LIC