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The Object-oriented Simulator of Marine ecoSystem Exploitation (OSMOSE) is one of the end-to-end models developed for ecosystem dynamic simulation and management strategy evaluation (MSE) in support of ecosystem-based fishery management (EBFM). However, the implementation of such integrated models has been limited due to lack of data, and their performance in advising fisheries management has been rarely evaluated. We developed an end-to-end model (OSMOSE-JZB) representing organisms of high and low trophic levels in the Jiaozhou Bay, a temperate bay in China with limited available data. We evaluated the performance of the model for simulating the ecosystem dynamics by comparing the model-predicted species biomass, size structure, trophic level, and mortality with relevant data derived from scientific surveys and literature. In general, the model-predicted species biomass and size ranges were consistent with observations. However, the size structure of the two dominant fish species showed some discrepancies between the model simulations and observations. The predicted mean trophic levels from OSMOSE-JZB were closer to the values derived from an Ecopath model of the same region, compared to the values derived from empirical isotope analysis. The model's output suggested that predation mortality appeared to be the main source of mortality for younger individuals compared to starvation and fishing mortality. This study suggests that the OSMOSE-JZB performs well under a data-poor situation and can be considered as a baseline ecosystem model for developing EBFM.

Soluble microbial products (SMP) formed by microorganisms in wastewater treatment plants (WWTPs) adversely affect final effluent quality and treatment efficiency. It is difficult to distinguish SMP from residual proteins, lipids and carbohydrates present in the influent that may persist during treatment. No method is currently available to determine quantitatively the extent to which SMP contribute to organic discharges from municipal WWTPs. In this work a modeling approach is presented which allows the SMP fraction of the effluent of a municipal WWTP to be quantified and described. The model is validated, in terms of utilization-associated products, biomass-associated products and extracellular polymeric substances, using influent from a municipal WWTP. SMP was found to account for, on average, 27 mg/L of chemical oxygen demand (COD), or 61% of the total COD in the WWTP effluent. Over 90% of the SMP was comprised of biomass-associated products. Five main factors influencing SMP formation in WWTP were evaluated. Neither wastewater composition nor mixed liquor suspended solids concentration was found to affect SMP production. On the other hand, a positive correlation was observed for SMP formation with both solids retention time and influent COD concentration, and a negative correlation with hydraulic retention time. Thus, operating or designing WWTPs with short solids retention and long hydraulic retention times could be considered as solutions for minimizing SMP production.

Microbial internal storage processes have been demonstrated to occur and play an important role in activated sludge systems under both aerobic and anoxic conditions when operating under dynamic conditions. High-rate anaerobic reactors are often operated at a high volumetric organic loading and a relatively dynamic profile, with large amounts of fermentable substrates. These dynamic operating conditions and high catabolic energy availability might also facilitate the formation of internal storage polymers by anaerobic microorganisms. However, so far information about storage under anaerobic conditions (e.g., anaerobic fermentation) as well as its consideration in anaerobic process modeling (e.g., IWA Anaerobic Digestion Model No. 1, ADM1) is still sparse. In this work, the accumulation of storage polymers during anaerobic fermentation was evaluated by batch experiments using anaerobic methanogenic sludge and based on mass balance analysis of carbon transformation. A new mathematical model was developed to describe microbial storage in anaerobic systems. The model was calibrated and validated by using independent data sets from two different anaerobic systems, with significant storage observed, and effectively simulated in both systems. The inclusion of the new anaerobic storage processes in the developed model allows for more successful simulation of transients due to lower accumulation of volatile fatty acids (correction for the overestimation of volatile fatty acids), which mitigates pH fluctuations. Current models such as the ADM1 cannot effectively simulate these dynamics due to a lack of anaerobic storage mechanisms.

Research in technology-enhanced learning (TEL) throughout the last decade has largely focused on sharing and reusing educational resources and data. This effort has led to a fragmented landscape of competing metadata schemas, such as IEEE LOM or ADL SCORM, and interface mechanisms, such as OAI-PMH, SQI and REST-ful services in general. More recently, semantic technologies were taken into account to improve interoperability. However, so far Web-scale integration of resources is not facilitated, mainly due to the lack of take-up of shared principles, datasets and schemas. On the other hand, the Linked Data approach has emerged as the de facto standard for sharing data on the Web and is fundamentally based on established W3C standards. This paper presents results of the European Commission-funded project mEducator, which exploits Linked Data principles for (1) semantic integration and (2) social interconnecting of educational data, resources and actors. We describe a general approach to exploit the wealth of already existing educational data on the Web by allowing its exposure as Linked Data and by taking into account automated enrichment and interlinking techniques to provide a rich and well-interlinked graph for the educational domain. Additionally, the paper presents an evaluation of our work with respect to a set of socio-semantic dimensions. Experimental results demonstrate improved interoperability and retrievability of the resulting resource descriptions as part of an interlinked resource graph.

A crucial requirement in the web of data is to describe datasets to facilitate acess, reuse, and interlinking. The mEducator project, a best practice netwrok on medical content sharing and repurposing has developed an RDF schema that departures from current learning metadata standards by adopting linked data principles.

Past research aiming at interoperability within the Technology- Enhanced Learning (TEL) field has led to a fragmented landscape of competing metadata schemas and interface mechanisms. So far, Web-scale integration of resources is not facilitated, mainly due to the lack of take-up of shared principles, datasets and schemas. On the other hand, the Linked Data approach has emerged as the de-facto standard for sharing data on the Web. We propose MetaMorphosis+, a social educational application which adopts a general approach to exploit existing TEL data on the Web by allowing its exposure as Linked Data and by taking into account automated enrichment and interlinking techniques to provide rich and well-interlinked data for the educational domain.

The existence of non-interoperable metadata schemas and limited use of shared vocabularies means that retrieving and processing educational resources across the Web represents a challenge. The emerging Linked Data paradigm has provided the tools and methods to share and expose metadata in a more unified and well interlinked manner, permitting both humans and machines to process Web data. The availability of vast amounts of RDF-based Linked Data is offering a worthwhile alternative to the isolated and heterogeneous data silos which previously dominated the Web. In the ECfunded project mEducator a standardised approach is proposed to describing and exposing medical educational resources. In this paper are described firstly the design considerations, and conceptual model upon which mEducator 's metadata scheme approach was based. Afterwards, follows the description of the serialization of the scheme in RDF/XML, and in turn follows an example showing how medical educational resources are exposed on the Web using an RDF endpoint, and discuss the potential advantages of this approach.