Development of an investment decision tool for biogas production from agricultural waste

Anaerobic digestion is a very promising solution for the treatment of agricultural waste, preventing pollution and leading to efficient energy production. Since this technology is available to each farmer in a different way depending on the location and the scattering of the primary sources, it is essential to clarify the best conditions adapted to local situations to treat the targeted residues and make this information accessible to farmers. In particular the possibility of codigestion seems to be very attractive for farmers who will be able to treat their own waste together with other organic substrates. Their profit in this case is double since they treat properly their own residues, taking advantage of the selling of heat and electricity as well as the utilisation of a stabilised biofertiliser. The aim of this paper is to present an investment decision kit for economic evaluation of biogas plant projects based on agricultural feedstocks.     

Theta-burst stimulation of the right neocerebellar vermis selectively disrupts the practice-induced acceleration of lexical decisions.

The present study reports an experiment of cerebellar transcranial magnetic stimulation in a lexical decision task. In contrast to the study by Argyropoulos (2011), no effect of cerebellar stimulation was observed on priming sizes. However, when subjects confronted the same stimuli in the second session of participation, lexical decision latencies did not become any shorter after stimulation of the right neocerebellar vermis, in contrast to all other conditions. This finding is discussed in the light of current research in cerebellar cognitive and linguistic functions, and provides some first evidence for the recently entertained hypothesis that neocerebellar loci are significant in acquiring, storing, and retrieving associative memory traces of repeatedly co-occurring neural events in the language domain. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

A new approach to the design of amperometric gas sensors

Preliminary experiments are described in order to demonstrate the principle of a new design of amperometric gas sensors. In this design, non-porous electrodes are all fabricated onto the gas side of a proton conducting medium so that the oxidation/reduction of the gas to be sensed occurs at the three phase interface between the atmosphere, the electrode and the proton conducting medium, i.e. the system approximates to a line electrode. Such a cell is described which gives good quality responses for the oxidation of SO₂ from the gas phase.     

A variational Bayesian methodology for hidden Markov models utilizing Student's-t mixtures

The Student's-t hidden Markov model (SHMM) has been recently proposed as a robust to outliers form of conventional continuous density hidden Markov models, trained by means of the expectation-maximization algorithm. In this paper, we derive a tractable variational Bayesian inference algorithm for this model. Our innovative approach provides an efficient and more robust alternative to EM-based methods, tackling their singularity and overfitting proneness, while allowing for the automatic determination of the optimal model size without cross-validation. We highlight the superiority of the proposed model over the competition using synthetic and real data. We also demonstrate the merits of our methodology in applications from diverse research fields, such as human computer interaction, robotics and semantic audio analysis.     

Wireless Convergence Architecture: A Case Study Using GSM and Wireless LAN

The evolution of wireless networks has motivated the expansion of the static business environment to a mobile and wireless one. However, current and forthcoming wireless technologies are characterized by different attributes, regarding coverage area, offered bandwidth and delay. The transparent conjunction of various wireless technologies into a single mobile terminal can further boost the wireless explosion. This paper presents the Wireless Convergence Architecture (WCA) that incorporates different wireless interfaces under the same mobile terminal. Depending on the location and the availability of the underlying wireless network, automatic and seamless switching is performed to the most appropriate wireless network interface. Special care is taken to maintain continuous connectivity at the transport layer (TCP). WCA introduces software components both at the terminal and network side. A specific implementation is presented, based on two complementary wireless technologies – in terms of coverage area – an IEEE 802.11-compliant in the short local and a GSM in the wide area. To demonstrate the operational correctness of the architecture, experiments were performed using standard and proprietary networking applications.     

EEG transient event detection and classification using association rules.

In this paper, a methodology for the automated detection and classification of transient events in electroencephalographic (EEG) recordings is presented. It is based on association rule mining and classifies transient events into four categories: epileptic spikes, muscle activity, eye blinking activity, and sharp alpha activity. The methodology involves four stages: 1) transient event detection; 2) clustering of transient events and feature extraction; 3) feature discretization and feature subset selection; and 4) association rule mining and classification of transient events. The methodology is evaluated using 25 EEG recordings, and the best obtained accuracy was 87.38%. The proposed approach combines high accuracy with the ability to provide interpretation for the decisions made, since it is based on a set of association rules.     

Joint source-channel coding for wireless object-based video communications utilizing data hiding.

In recent years, joint source-channel coding for multimedia communications has gained increased popularity. However, very limited work has been conducted to address the problem of joint source-channel coding for object-based video. In this paper, we propose a data hiding scheme that improves the error resilience of object-based video by adaptively embedding the shape and motion information into the texture data. Within a rate-distortion theoretical framework, the source coding, channel coding, data embedding, and decoder error concealment are jointly optimized based on knowledge of the transmission channel conditions. Our goal is to achieve the best video quality as expressed by the minimum total expected distortion. The optimization problem is solved using Lagrangian relaxation and dynamic programming. The performance of the proposed scheme is tested using simulations of a Rayleigh-fading wireless channel, and the algorithm is implemented based on the MPEG-4 verification model. Experimental results indicate that the proposed hybrid source-channel coding scheme significantly outperforms methods without data hiding or unequal error protection.     

Direct Observation at Room Temperature of the Orthorhombic Weyl Semimetal Phase in Thin Epitaxial MoTe2

The direct observation at room temperature (RT) of the noncentrosymmetric orthorhombic topological Weyl semimetal phase in epitaxial thin films of MoTe₂ grown on InAs(111)/Si(111) substrates by molecular beam epitaxy (MBE) is reported. The orthorhombic phase is typically found at lower temperatures but its observation at RT in this work is attributed to the enlarged lattice parameters, influenced by the substrate, which stabilize an interlayer antibonding state compatible with the orthorhombic stacking. First‐principles calculations predict eight type II Weyl nodes which are located below (but near) the Fermi energy making them accessible to charge transport and creating the prospect for practical applications exploiting the nontrivial topological properties. The orthorhombic phase coexists with an unconventional triclinic layer stacking which is different than the monoclinic or orthorhombic structures but it is centrosymmetric and topologically trivial.     

Transforming traditional production system transactions to interoperable eBusiness-aware systems with the use of generic process models

Through the years, successful enterprises have been identified as the ones that were able to adapt their processes and ways of conducting business to the needs of their environment and the technological achievements of their times. This statement has not changed during recent years, but today, due to the major breakthrough of the internet and the possibilities it offers for a unified electronic marketplace, enterprises have to take advantage of the new technological tools offered, in order not only to adapt to this new emerging environment, but also to benefit from it and expand their operations in parallel with minimising costs. Achieving interoperability of the various production systems, and not only enabling hard-wired connectivity, seems to be the key that will unlock the gates leading to this newly established global market, and therefore enterprises need to focus more on their already established processes in order to be able to formulate a global standard for executing business transactions and cooperating smoothly with each other.     

The effect of heparin hydrogel embedding on glutaraldehyde fixed bovine pericardial tissues: Mechanical behavior and anticalcification potential

Heart valve diseases remain common in industrialized countries. Bioprosthetic heart valves, introduced as free of anticoagulation therapy alternatives to mechanical substitutes. Still they suffer from long term failure due to calcification. Different treatment methods introduced to inhibit calcification, have so far been limited in success. Glycosaminoglycans (GAGs) possess properties including high negative charge, anticoagulation and anti-inflammatory activity that make them a potential solution for calcification problem. In this study, heparin hydrogel was prepared and characterized both chemically and mechanically. After that, heparin hydrogel embedded bovine pericardial tissues, fixed with glutaraldehyde, were produced and tested for their mechanical behavior and anticalcifcation potential in vitro using the constant composition model. In the calcification experiments, tissues were divided into three groups: a) Controls without treatment, b) Hydrogel treated tissues and c) Tissues with raw heparin dissolved in the calcification solution. The results showed that embedding of tissue with hydrogel had no stiffening effect on its mechanical behavior. Calcification assessment showed a significant efficacy on inhibition of calcium phosphate deposition of hydrogel treated (second group) in comparison to untreated tissues (control, first group). Calcification inhibition potential was very similar in both the second and raw heparin (third group). Histological data confirmed the obtained results, suggesting that heparin treatment is a promising anticalcification agent.

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