Sustainable reference methodology for energy end-use efficiency data in the EU

One of the most important goals of the European energy policy involves the implementation of energy-efficiency measures in large scale so as to promote sustainable development in the European Union (EU) level. The multidimensional character of energy end-use efficiency (EEE) necessitates the collection of a number of related data, apart from the performance and system parameters data, such as socio-economic (e.g., employment, turnover) and Research and Development (R&D) expenditures. Moreover, improved co-ordination of EEE programmes and policies of the community and the member states so as a unified acceptable system to be developed for the monitoring of the EEE data with respect to the existing targets is of significant importance. Even though data-gathering efforts have been implemented, a lot of fragmented data and deduced findings are currently available, which sometimes lack consistency and verification. In this context, the main aim of the paper is to present a sustainable reference methodology for validating EEE data in EU, through the review of existing approaches and methods, defining of most relevant inconsistencies and gaps and provision of recommendations for improvements in EEE data aggregation and statistical interpretation, taking into consideration the related analysis of statisticians, energy technology experts and energy socio-economists.     

Picosecond grating spectroscopy for characterizing the acoustic properties of biological material

We present measurements of the ultrasound attenuation and sound velocity of a number of liquids, transparent biological materials (the vitreous and lens of the bovine eye), and biological fluids (whole blood) at frequencies between 925 and 1020 MHz by using a picosecond thermal grating. Sound velocity and attenuation measurements of liquids (e.g., methanol and ethanol) agree very well with those reported in the literature. The sound velocity in the biological materials studied also agrees with the reported values in the literature. In contrast, the attenuation coefficients measured for biological materials, 2000-5000 dB/cm, are much higher than would be extrapolated from published low-frequency data.     

Human resource optimisation through semantically enriched data

The industrial domain is experiencing a so-called fourth industrial revolution in which the evergrowing complexity of manufacturing information, the increasing amount of knowledge and the use of web-oriented techniques, represent three crucial factors that are accelerating the growth of complexity of industrial systems. On the other hand, continuous-evolving requirements in industrial environments, due to technology outbreaks and a new global marketplace, have led to an on-going evolution of human resource management through the creation and adoption of alternative business models. In the past decade, semantic models such as ontologies have been proven to be effective for many knowledge-intensive applications, since they provide formal models of domain knowledge that can be exploited in different ways. For all these reasons, an innovative human resource optimisation (HRO) engine is introduced, which employs semantically enhanced information and conditional random field (CRFs) probabilistic models with knowledge derived from industrial shop floor level, and proposes the right person for the right job in real-time shop floor operations towards optimising decisions on how to implement and schedule either repeatedly or non-occurring tasks. Industrial information data flow and semantic enrichment were ensured through the combined use of a common interface data exchange model (CIDEM) and ontologies, after which a feasibility study at a chemical plant presented interesting preliminary results.     

The promoting effect of Fe on Ni/GDC for the Solid Oxide H2O electrolysis

The study deals with the modification of commercial Ni/GDC powder with iron and its use as fuel functional electrode for Solid Oxide H₂O electrolysis. The Fe-NiO/GDC samples were prepared with the Deposition-Precipitation method and characterized, in their oxidized and reduced form, by using BET, HR-TEM, SAED, XRD, XPS and TG analysis in the presence of H₂O. The electrochemical investigation deals with the comparison of single SOECs at 900°C, under various pH₂O/pH₂ ratios. In the oxidized powders iron was detected, both in the bulk and on the surface, in the form of crystallized Fe₂O₃ species, which during H₂-reduction interacted with NiO towards the formation of a Ni-Fe alloy. The latter promoted the electrochemical performance of the Fe-Ni/GDC electrodes, where there are indications of strong dependence on the Fe wt% content. Specifically, the performance of the cell with 0.5 wt% Fe-Ni/GDC was threefold higher than that with Ni/GDC. On the other hand, the cell with 2 wt% Fe-Ni/GDC was worse, implying that the promoting effect of Fe lies on quite low wt% content. Finally, the examined Fe-doped electrodes exhibited increase of polarization in high pH₂O. This is primarily ascribed to the fact that Fe-Ni/GDC electrodes seem more susceptible to H₂O oxidation. Overall, Fe is considered as a promising Ni/GDC dopant, capable to substitute noble metals like Au, but further investigation is required for the elucidation of key preparation and performance parameters.     

Comparison of examination methods based on multiple-choice questions and constructed-response questions using personal computers

The aim of the present research was to compare the use of multiple-choice questions (MCQs) as an examination method, to the examination based on constructed-response questions (CRQs). Despite that MCQs have an advantage concerning objectivity in the grading process and speed in production of results, they also introduce an error in the final formulation of the score. The error is traced to the probability of answering a question by chance or based on an instinctive feeling, which does not enable the ascertainment of the knowledge of the whole background included in the question. In the present study, both MCQ and CRQ tests were given to examinees, in the framework of a computer-based learning system. Avoiding the procedure of mixed scoring, e.g. both positive and negative markings, a set of pairs of MCQs was composed. The MCQs in each pair were similar concerning the same topic, but this similarity was not evident for an examinee that did not possess adequate knowledge on the topic addressed in the questions of the pair. The examination based on these “paired” MCQs, by using a suitable scoring rule, when made to the same sample of students, οn the same topics and with the same levels of difficulty, gave results that were statistically indistinguishable with the grades produced by an examination based on CRQs, while both the “paired” MCQ test results and the CRQ test results differed significantly from those obtained from a MCQ test using positive-only scoring rule.     

Application of microwave-assisted extraction to the fast extraction of plant phenolic compounds

The analysis of phenolic compounds in plants attracts considerable attention. Conventional (reflux) extraction as well as microwave-assisted extraction of phenolic substances from aromatic plants using different solvents has been studied. RP-HPLC with UV detection was employed for the analysis of phenolic compounds. Total phenolic compounds were determined by the Folin-Ciocalteu assay. The amount of extractable phenolic substances for this method decreased with decreasing polarity of the solvent in the order water, 60% methanol, 60% acetone, and ethyl acetate/water (60:30, v/v) by using the conventional method. When microwave-assisted extraction was performed, the previous order was changed to 60% acetone, 60% methanol, water and ethyl acetate/water. The HPLC results have shown similar solvent effect for the two extraction methods. It was also proved that microwave-assisted extraction is a more effective technique compared to the conventional method. The extraction time was reduced, less solvent was used and the amount of extracted phenolic compounds was increased.     

Chitosan/gelatin scaffolds support bone regeneration

Chitosan/Gelatin (CS:Gel) scaffolds were fabricated by chemical crosslinking with glutaraldehyde or genipin by freeze drying. Both crosslinked CS:Gel scaffold types with a mass ratio of 40:60% form a gel-like structure with interconnected pores. Dynamic rheological measurements provided similar values for the storage modulus and the loss modulus of the CS:Gel scaffolds when crosslinked with the same concentration of glutaraldehyde vs. genipin. Compared to genipin, the glutaraldehyde-crosslinked scaffolds supported strong adhesion and infiltration of pre-osteoblasts within the pores as well as survival and proliferation of both MC3T3-E1 pre-osteoblastic cells after 7 days in culture, and human bone marrow mesenchymal stem cells (BM-MSCs) after 14 days in culture. The levels of collagen secreted into the extracellular matrix by the pre-osteoblasts cultured for 4 and 7 days on the CS:Gel scaffolds, significantly increased when compared to the tissue culture polystyrene (TCPS) control surface. Human BM-MSCs attached and infiltrated within the pores of the CS:Gel scaffolds allowing for a significant increase of the osteogenic gene expression of RUNX2, ALP, and OSC. Histological data following implantation of a CS:Gel scaffold into a mouse femur demonstrated that the scaffolds support the formation of extracellular matrix, while fibroblasts surrounding the porous scaffold produce collagen with minimal inflammatory reaction. These results show the potential of CS:Gel scaffolds to support new tissue formation and thus provide a promising strategy for bone tissue engineering.     

KnowBaSICS-M: an ontology-based system for semantic management of medical problems and computerised algorithmic solutions

In this paper, an ontology-based system (KnowBaSICS-M) is presented for the semantic management of Medical Computational Problems (MCPs), i.e., medical problems and computerised algorithmic solutions. The system provides an open environment, which: (1) allows clinicians and researchers to retrieve potential algorithmic solutions pertinent to a medical problem and (2) enables incorporation of new MCPs into its underlying Knowledge Base (KB). KnowBaSICS-M is a modular system for MCP acquisition and discovery that relies on an innovative ontology-based model incorporating concepts from the Unified Medical Language System (UMLS). Information retrieval (IR) is based on an ontology-based Vector Space Model (VSM) that estimates the similarity among user-defined MCP search criteria and registered MCP solutions in the KB. The results of a preliminary evaluation and specific examples of use are presented to illustrate the benefits of the system. KnowBaSICS-M constitutes an approach towards the construction of an integrated and manageable MCP repository for the biomedical research community.     

3D Variable Density Flow Simulation to Evaluate Pumping Schemes in Coastal Aquifers

A three dimensional model is presented for the simulation of seawater intrusion in coastal aquifers by considering the development of a transition zone and thus the variable density flow approach. The model is applied to a heterogeneous coastal aquifer to study the effects of the pumping rate, the salinity of freshwater inflow and the thickness of the aquifer, on the degradation of pumped water quality through wells in certain location. Even for an optimum pumping scheme solution based on a simple two-dimensional flow model, we simulate freshwater degradation in pumped water which depends on the salinity of freshwater inflow and aquifer thickness.