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In this survey, we present state-of-the-art bitrate adaptation algorithms for HTTP adaptive streaming (HAS). As a key distinction from other streaming approaches, the bitrate adaptation algorithms in HAS are chiefly executed at each client, i.e., in a distributed manner. The objective of these algorithms is to ensure a high quality of experience (QoE) for viewers in the presence of bandwidth fluctuations due to factors like signal strength, network congestion, network reconvergence events, etc. While such fluctuations are common in public Internet, they can also occur in home networksor even managed networks where there is often admission control and QoS tools. Bitrate adaptation algorithms may take factors like bandwidth estimations, playback buffer fullness, device features, viewer preferences, and content features into account, albeit with different weights. Since the viewer's QoE needs to be determined in real-time during playback, objective metrics are generally used including number of buffer stalls, duration of startup delay, frequency and amount of quality oscillations, and video instability. By design, the standards for HAS do not mandate any particular adaptation algorithm, leaving it to system builders to innovate and implement their own method. This survey provides an overview of the different methods proposed over the last several years.

Iron deficiency remains a major global health problem affecting an estimated 2 billion people. The World Health Organization ranked it as the seventh most important preventable risk for disease, disability, and death in 2002. Since an important factor in its causation is the poor bioavailability of iron in the cereal-based diets of many developing countries, SUSTAIN set up a Task Force, consisting of nutritional, medical, industry, and government experts to consider strategies for enhancing the absorption of fortification iron. This paper summarizes the findings of this Task Force. Detailed reviews of each strategy follow this overview. Highly soluble compounds of iron like ferrous sulfate are desirable food fortificants but cannot be used in many food vehicles because of sensory issues. Thus, potentially less well-absorbed forms of iron commonly are used in food fortification. The bioavailability of iron fortificants can, however, be enhanced with innovative ingredient technologies. Ascorbic acid, NaFeEDTA, ferrous bisglycinate, and dephytinization all enhance the absorption of fortification iron, but add to the overall costs of fortification. While all strategies cannot be recommended for all food fortification vehicles, individual strategies can be recommended for specific foods. For example, the addition of ascorbic acid is appropriate for dry blended foods such as infant foods and other dry products made for reconstitution that are packaged, stored, and prepared in a way that maximizes retention of this vitamin. NaFeEDTA can be recommended for fortification of fish sauce and soy sauce, whereas amino acid chelates may be more useful in milk products and beverages. With further development, dephytinization may be possible for low-cost, cereal-based complementary foods in developing countries. Encapsulation of iron salts in lipid coatings, while not an iron absorption-enhancing strategy per se, can prevent soluble forms of iron from interacting undesirably with some food vehicles and hence broaden the application of some fortificants. Research relevant to each of these strategies for enhancing the bioavailability or utility of iron food fortificants is reviewed. Individual strategies are evaluated in terms of enhancing effect and stability, organoleptic qualities, cost, and regulatory issues of interest to the nutrition community, industry, and consumers. Recommendations are made on potential usages and further research needs. Effective fortification depends on the selection of technically feasible and efficacious strategies. Once suitable strategies have been identified, cost becomes very important in selecting the best approach to implement. However it is essential to calculate cost in relation to the amount of bioavailable iron delivered. An approach to the calculation of cost using a conservative estimate of the enhancing effects of the innovative technologies discussed in the supplement is given in the final section.

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Video sensors are becoming ubiquitous and the volume of captured video material is very large. Therefore, tools for searching video databases are indispensable. Current techniques that extract features purely based on the visual signals of a video are struggling to achieve good results. By considering video related meta-information, more relevant and precisely delimited search results can be obtained. In this study we propose a novel approach for querying videos based on the notion that the geographical location of the captured scene in addition to the location of a camera can provide valuable information and may be used as a search criterion in many applications. This study provides an estimation model of the viewable area of a scene for indexing and searching and reports on a prototype implementation. Among our objectives is to stimulate a discussion of these topics in the research community as information fusion of different georeferenced data sources is becoming increasingly important. Initial results illustrate the feasibility of the proposed approach.