Interface Mutation Test Adequacy Criterion: An Empirical Evaluation

An experiment was conducted to evaluate an inter-procedural test adequacy criterion named Interface Mutation. Program SPACE, developed for the European Space Agency (ESA), was used in this experiment. The development record available for this program was used to find the faults uncovered during its development. Using this information the test process was reproduced starting with a version of SPACE containing several faults and then applying Interface Mutation. Thus we could evaluate the fault revealing effectiveness of Interface Mutation. Results from the experiment suggest that (a) the application of Interface Mutation favors the selection of fault revealing test cases when they exist and (b) Interface Mutation tends to select fault revealing test cases more efficiently than in the case where random selection is used.     

Failure mechanisms of repair mortar stone interface assessed by pull-off strength tests

Bulletin of Engineering Geology and the Environment - Adhesion strength between porous limestone and 8 repair mortars (4 commercial and 4 laboratory mixture) was tested. The composition of repair...     

Performance characterization of a novel Fe-based sorbent for anaerobic gas desulfurization finalized to high temperature fuel cell applications

A novel sorbent (SCX) composed of mixed iron oxides and hydroxides was studied to assess its suitability for H₂S removal from biogas finalized to high temperature fuel cell systems. From an industrial point of view, the potential usage of this product would have a beneficial impact on operational costs, since it is less expensive than activated carbons. Moreover, it is a non-hazardous landfilled product with a reduced environmental impact and it can be easily regenerated.Sorbent SCX was tested in different operative conditions, evaluating the influence on sorption capacity of gas hourly space velocity (GHSV), gas composition (inlet H₂S concentration, gas matrix, humidity), reactor temperature and filter geometry. As main outcomes, the experimentation highlighted: i) a hyperbolic increase in adsorption capacity as GHSV decreased, ii) a parabolic performance enhancement with increasing temperature and iii) a negative effect of humidity.Moreover, a comparison with commercial activated carbons typically used for the same purpose (Cu–Cr or KOH–KI treated) was performed, identifying the optimal operative parameters to obtain higher H₂S sorption capacity for SCX sorbent. Specifically, SCX showed its potential in terms of H₂S removal for GHSV lower than 330 h^?1, values of particular interest for many practical applications. In this case, an improved removal capability is obtained with respect to the ones exhibited by the considered carbons. Moreover, quantitative evaluations provided for unitary installed power (1 kW_e fuel cell-based systems) highlighted the possibility to have more compact (volume reduction of about 50%) and cheaper (cost reduction up to six times) filters.     

Adaptive output‐feedback stabilisation of an uncertain second‐order linear systems

The adaptive stabilisation of uncertain second‐order linear systems is addressed, under a lack of information from both states and parameters. The only standard assumptions are no zeros and the sign of the high frequency gain known. To the best of the authors' knowledge, there has been only an explicit solution proposed in the literature so far with proven stability. Despite the simplicity of the system, it does not fit in any of the standard nonlinear control methodologies available. Thus, this work is a complementary contribution providing a mixed control design strategy based on a reduced‐order observer, adaptive Immersion & Invariance and Backstepping approaches. Hence, this solution depicts a transversal outlook of those nonlinear control strategies and provides a breakthrough for the generalisation of this non‐trivial control problem. Numerical simulations are reported to assess the effectiveness of the adaptive strategy. Copyright © 2016 John Wiley & Sons, Ltd.     

Extending multimedia languages to support multimodal user interactions

Historically, the Multimedia community research has focused on output modalities, through studies on timing and multimedia processing. The Multimodal Interaction community, on the other hand, has focused on user-generated modalities, through studies on Multimodal User Interfaces (MUI). In this paper, aiming to assist the development of multimedia applications with MUIs, we propose the integration of concepts from those two communities in a unique high-level programming framework. The framework integrates user modalities —both user-generated (e.g., speech, gestures) and user-consumed (e.g., audiovisual, haptic)— in declarative programming languages for the specification of interactive multimedia applications. To illustrate our approach, we instantiate the framework in the NCL (Nested Context Language) multimedia language. NCL is the declarative language for developing interactive applications for Brazilian Digital TV and an ITU-T Recommendation for IPTV services. To help evaluate our approach, we discuss a usage scenario and implement it as an NCL application extended with the proposed multimodal features. Also, we compare the expressiveness of the multimodal NCL against existing multimedia and multimodal languages, for both input and output modalities.

     

Technological ecosystems and ontologies for an educational model based on Web 3.0

Universal Access in the Information Society - Active learning promotes knowledge creation as a learning strategy for students working both individually and cooperatively. Learning 2.0 supported by...     

Synthesis of verifiable concurrent Java components from formal models

Software and Systems Modeling - Concurrent systems are hard to program, and ensuring quality by means of traditional testing techniques is often very hard as errors may not show up easily and...     

Prediction models for performance,power, and energy efficiency of software executed on heterogeneous hardware

The Journal of Supercomputing - Heterogeneous computer environments are becoming commonplace so it is increasingly important to understand how and where we could execute a given algorithm the most...