A test generation framework for quiescent real-time systems

We present an extension of Tretmans theory and algorithm for test generation for input-output transition systems to real-time systems. Our treatment is based on an operational interpretation of the notion of quiescence in the context of real-time behaviour. This gives rise to a family of implementation relations parameterized by observation durations for quiescence. We define a nondeterministic (parameterized) test generation algorithm that generates test cases that are sound with respect to the corresponding implementation relation. Also, the test generation is exhaustive in the sense that for each non-conforming implementation a test case can be generated that detects the non-conformance

Estudio mineralógico, textural y físico-mecánico de morteros de cal hidráulica curados en distintas condiciones de humedad relativa

This work focuses on the chemical-mineralogical, textural and physical-mechanical properties of hydraulic lime mortars made with siliceous and calcareous aggregate. Mortars were cured at 60% and 90% of relative humidity, so as to assess the variability of mortar petrophysical properties in the hardened state due to the moisture conditions. The final aim was to determine the most adequate moisture conditions to be maintained during application and hardening of hydraulic mortars intended for repair interventions. We found out that using a calcareous aggregate and curing mortar at 90% of relative humidity give place to better textural and mechanical properties. However, these characteristics mostly depend on the maximum size of the aggregate grains, which should be smaller than 6 mm, in order to avoid the occurrence of mechanical discontinuities in the mortar.En este trabajo se han estudiado las propiedades químico-mineralógicas, texturales y físico-mecánicas de morteros de cal hidráulica elaborados con áridos silíceo y calcítico. Estos morteros se han curado al 60% y 90% de humedad relativa, con el fin de evaluar las eventuales diferencias en las propiedades petrofísicas de los morteros una vez endurecidos y así establecer cuál de los dos ambientes es recomendable durante la aplicación y fraguado de morteros de cal hidráulica destinados a obras de restauración. Se ha encontrado que el uso de un árido de composición calcítica y el curado al 90% de humedad relativa dan lugar a morteros hidráulicos con mejores características texturales y propiedades mecánicas. De todas formas, estas características dependen principalmente del tamaño máximo del árido empleado, que debería ser inferior a 6 mm para evitar discontinuidades mecánicas en el mortero.This study was financially supported by the Spanish research group RNM179 of the Junta de Andalucía, by the research project MAT-2012-34473 and by the Institute of Conservation and Restoration of Cultural Heritage of the CICOP foundation (ICON-CICOP)

Managing plagiarism in programming assignments with blended assessment and randomisation.

Plagiarism is a common concern for coursework in many situations, particularly where electronic solutions can be provided e.g. computer programs, and leads to unreliability of assessment. Written exams are often used to try to deal with this, and to increase reliability, but at the expense of validity. One solution, outlined in this paper, is to randomise the work that is set for students so that it is very unlikely that any two students will be working on exactly the same problem set. This also helps to address the issue of students trying to outsource their work by paying external people to complete their assignments for them. We examine the effectiveness of this approach and others (including blended assessment) by analysing the spread of similarity scores across four different introductory programming assignments to find the natural similarity i.e. the level of similarity that could reasonably occur without plagiarism. The results of the study indicate that divergent assessment (having more than one possible solution) as opposed to convergent assessment (only one solution) is the dominant factor in natural similarity. A key area for further work is to apply the analysis to a larger sample of programming assignments to better understand the impact of different features of the assignment design on natural similarity and hence the detection of plagiarism

Looking back and moving forward

This chapter brings together the research on teacher resilience and approaches to supporting resilience and wellbeing discussed in this volume. As many of the approaches utilised aspects of the BRiTE and Staying BRiTE projects, I highlight common themes as well as the different ways the authors developed and implemented their work to reflect their specific contexts and participants. I also reflect on broader issues related to conceptualisation of resilience, consider where responsibility for resilience lies, and explore future directions. The chapter also provides some insights regarding the collegial collaboration that has made the body of work possible

Testing real-time systems using TINA

The paper presents a technique for model-based black-box conformance testing of real-time systems using the Time Petri Net Analyzer TINA. Such test suites are derived from a prioritized time Petri net composed of two concurrent sub-nets specifying respectively the expected behaviour of the system under test and its environment.We describe how the toolbox TINA has been extended to support automatic generation of time-optimal test suites. The result is optimal in the sense that the set of test cases in the test suite have the shortest possible accumulated time to be executed. Input/output conformance serves as the notion of implementation correctness, essentially timed trace inclusion taking environment assumptions into account. Test cases selection is based either on using manually formulated test purposes or automatically from various coverage criteria specifying structural criteria of the model to be fulfilled by the test suite. We discuss how test purposes and coverage criterion are specified in the linear temporal logic SE-LTL, derive test sequences, and assign verdicts

Murine CD1d-Restricted T Cell Recognition of Cellular Lipids

AbstractNKT cells are associated with immunological control of autoimmune disease and cancer and can recognize cell surface mCD1d without addition of exogenous antigens. Cellular antigens presented by mCD1d have not been identified, although NKT cells can recognize a synthetic glycolipid, α-GalCer. Here we show that after addition of a lipid extract from a tumor cell line, plate-bound mCD1d molecules stimulated an NKT cell hybridoma. This hybridoma also responded strongly to three purified phospholipids, but failed to recognize α-GalCer. Seven of sixteen other mCD1d restricted hybridomas also showed a response to certain purified phospholipids. These findings suggest NKT cells can recognize cellular antigens distinct from α-GalCer and identify phospholipids as potential self-antigens presented by mCD1d

Testing timed systems modeled by stream X-machines

Stream X-machines have been used to specify real systems where complex data structures. They are a variety of extended finite state machine where a shared memory is used to represent communications between the components of systems. In this paper we introduce an extension of the Stream X-machines formalism in order to specify systems that present temporal requirements. We add time in two different ways. First, we consider that (output) actions take time to be performed. Second, our formalism allows to specify timeouts. Timeouts represent the time a system can wait for the environment to react without changing its internal state. Since timeous affect the set of available actions of the system, a relation focusing on the functional behavior of systems, that is, the actions that they can perform, must explicitly take into account the possible timeouts. In this paper we also propose a formal testing methodology allowing to systematically test a system with respect to a specification. Finally, we introduce a test derivation algorithm. Given a specification, the derived test suite is sound and complete, that is, a system under test successfully passes the test suite if and only if this system conforms to the specification

Comparing uni-modal and multi-modal therapies for improving writing in acquired dysgraphia after stroke.

Writing therapy studies have been predominantly uni-modal in nature; i.e., their central therapy task has typically been either writing to dictation or copying and recalling words. There has not yet been a study that has compared the effects of a uni-modal to a multi-modal writing therapy in terms of improvements to spelling accuracy. A multiple-case study with eight participants aimed to compare the effects of a uni-modal and a multi-modal therapy on the spelling accuracy of treated and untreated target words at immediate and follow-up assessment points. A cross-over design was used and within each therapy a matched set of words was targeted. These words and a matched control set were assessed before as well as immediately after each therapy and six weeks following therapy. The two approaches did not differ in their effects on spelling accuracy of treated or untreated items or degree of maintenance. All participants made significant improvements on treated and control items; however, not all improvements were maintained at follow-up. The findings suggested that multi-modal therapy did not have an advantage over uni-modal therapy for the participants in this study. Performance differences were instead driven by participant variables

Atmospheric turbulence triggers pronounced diel pattern in karst carbonate geochemistry

CO2 exchange between terrestrial ecosystems and the atmosphere is key to understanding the feedbacks between climate change and the land surface. In regions with carbonaceous parent material, CO2 exchange patterns occur that cannot be explained by biological processes, such as disproportionate outgassing during the daytime or nighttime CO2 uptake during periods when all vegetation is senescent. Neither of these phenomena can be attributed to carbonate weathering reactions, since their CO2 exchange rates are too small. Soil ventilation induced by high atmospheric turbulence is found to explain atypical CO2 exchange between carbonaceous systems and the atmosphere. However, by strongly altering subsurface CO2 concentrations, ventilation can be expected to influence carbonate weathering rates. By imposing ventilation-driven CO2 outgassing in a carbonate weathering model, we show here that carbonate geochemistry is accelerated and does play a surprisingly large role in the observed CO2 exchange pattern of a semi-arid ecosystem. We found that by rapidly depleting soil CO2 during the daytime, ventilation disturbs soil carbonate equilibria and therefore strongly magnifies daytime carbonate precipitation and associated CO2 production. At night, ventilation ceases and the depleted CO2 concentrations increase steadily. Dissolution of carbonate is now enhanced, which consumes CO2 and largely compensates for the enhanced daytime carbonate precipitation. This is why only a relatively small effect on global carbonate weathering rates is to be expected. On the short term, however, ventilation has a drastic effect on synoptic carbonate weathering rates, resulting in a pronounced diel pattern that exacerbates the non-biological behavior of soil–atmosphere CO2 exchanges in dry regions \mbox{with carbonate soils}.M. Roland was granted by the Institute for Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). I. A. Janssens and R. Van Grieken acknowledge the Research Foundation – Flanders (FWO). P. Serrano-Ortiz is funded by a postdoctoral fellowship from the Spanish Ministry of Science and Innovation. S. Cuezva was funded by a postdoctoral fellowship from the Spanish Ministry of Science and Innovation, research programme Juan de la Cierva