7,665 research outputs found
Verifying and Testing Asynchronous Circuits using LOTOS (extended version)
It is shown howDILL (Digital Logic in LOTOS) can be used to specify,verify and test asynchronous hardware designs. Asynchronous (unclocked) circuits are a topic of active research in the hardware community. It is illustrated how DILL can address some of the key challenges. New relations for (strong) conformance are defined for assessing a circuit implementation against its specification. An algorithm is also presented for generating and applying implementation tests based on a specification. Tools have been developed for automated verification of conformance and generation of tests. The approach is illustrated with three case studies that explore speed independence, delay sensitivity and testing of sample asynchronous circuit designs
Formally-Based Design Evaluation (extended version)
This paper investigates specification, verification and test generation for synchronous and asynchronous circuits. The approach is called DILL (Digital Logic in LOTOS). DILL models are discussed for synchronous and asynchronous circuits. Relations for (strong) conformance are defined for verifying a design specification against a high-level specification. An algorithm is also outlined for generating and applying implementation tests based on a specification. Tools have been developed for automated test generation and verification of conformance between an implementation and its specification. The approach is illustrated with various benchmark circuits as case studies
Specifying and Realising Interactive Voice Services
VoiceXML (Voice Extended Markup Language) has become a major force in interactive voice services. However current approaches to creating Voice-XML services are rather low-level. Graphical representations of VoiceXML are close to the textual form of the language, and do not give a high-level description of a service. CRESS (Chisel Representation Employing Systematic Specification) can be used to give a more abstract, language-independent view of interactive voice services. CRESS is automatically compiled into VoiceXML for implementation, and into LOTOS (Language Of Temporal Ordering Specification) or SDL (Specification and Description Language) for automated analysis. The paper explains how CRESS is translated into VoiceXML and LOTOS
The spectroscopic parameters of sodium cyanide, NaCN (X 1A'), revisited
The study of the rotational spectrum of NaCN (X A') has recently been
extended in frequency and in quantum numbers. Difficulties have been
encountered in fitting the transition frequencies within experimental
uncertainties. Various trial fits traced the difficulties to the incomplete
diagonalization of the Hamiltonian. Employing fewer spectroscopic parameters
than before, the transition frequencies could be reproduced within experimental
uncertainties on average. Predictions of -type -branch transitions with
up to 570 GHz should be reliable to better than 1 MHz. In addition,
modified spectroscopic parameters have been derived for the 13C isotopic
species of NaCN.Comment: 5 pages, no figure, J. Mol. Spectrosc., appeared; CDMS links update
The N-Body Problem in LOTOS
It is shown how the classical n-body problem in mechanics can be generalised and formalised in LOTOS. A number of variants are produced by instantiation of the specification framework. These include Newton’s cradle, gas motion, the ‘game of life’, an orrery, a space game, an air traffic simulation and a sailing race. It is shown how these are derived from the generic framework using a configuration tool. The resulting LOTOS specifications are simulated automatically to graphically animate the system behaviour
The uncertainty surrounding the burden of post-acute consequences of dengue infection
Post-acute consequences currently form a significant component of the dengue disability-adjusted life year (DALY) burden estimates. However, there is considerable uncertainty regarding the incidence, duration, and severity of these symptoms. Further research is needed to more accurately estimate the health and economic burden of these dengue manifestations
Label-invariant models for the analysis of meta-epidemiological data.
Rich meta-epidemiological data sets have been collected to explore associations between intervention effect estimates and study-level characteristics. Welton et al proposed models for the analysis of meta-epidemiological data, but these models are restrictive because they force heterogeneity among studies with a particular characteristic to be at least as large as that among studies without the characteristic. In this paper we present alternative models that are invariant to the labels defining the 2 categories of studies. To exemplify the methods, we use a collection of meta-analyses in which the Cochrane Risk of Bias tool has been implemented. We first investigate the influence of small trial sample sizes (less than 100 participants), before investigating the influence of multiple methodological flaws (inadequate or unclear sequence generation, allocation concealment, and blinding). We fit both the Welton et al model and our proposed label-invariant model and compare the results. Estimates of mean bias associated with the trial characteristics and of between-trial variances are not very sensitive to the choice of model. Results from fitting a univariable model show that heterogeneity variance is, on average, 88% greater among trials with less than 100 participants. On the basis of a multivariable model, heterogeneity variance is, on average, 25% greater among trials with inadequate/unclear sequence generation, 51% greater among trials with inadequate/unclear blinding, and 23% lower among trials with inadequate/unclear allocation concealment, although the 95% intervals for these ratios are very wide. Our proposed label-invariant models for meta-epidemiological data analysis facilitate investigations of between-study heterogeneity attributable to certain study characteristics
Using Epigenetic Networks for the Analysis of Movement Associated with Levodopa Therapy for Parkinson's Disease
© 2016 The Author(s) Levodopa is a drug that is commonly used to treat movement disorders associated with Parkinson's disease. Its dosage requires careful monitoring, since the required amount changes over time, and excess dosage can lead to muscle spasms known as levodopa-induced dyskinesia. In this work, we investigate the potential for using epiNet, a novel artificial gene regulatory network, as a classifier for monitoring accelerometry time series data collected from patients undergoing levodopa therapy. We also consider how dynamical analysis of epiNet classifiers and their transitions between different states can highlight clinically useful information which is not available through more conventional data mining techniques. The results show that epiNet is capable of discriminating between different movement patterns which are indicative of either insufficient or excessive levodopa
Narrowband tunable filter based on velocity-selective optical pumping in an atomic vapor
We demonstrate a tunable, narrow-band filter based on optical-pumping-induced
circular dichroism in rubidium vapor. The filter achieves a peak transmission
of 14.6%, a linewidth of 80 MHz, and an out-of-band extinction >35 dB. The
transmission peak can be tuned within the range of the Doppler linewidth of the
D1 line of atomic rubidium at 795 nm. While other atomic filters work at
frequencies far from absorption, the presented technique provides light
resonant with atomic media, useful for atom-photon interaction experiments. The
technique could readily be extended to other alkali atoms.Comment: 3 Pages, 4 figure
Electrochemistry education in the twenty-first century: the current landscape in the UK, challenges and opportunities
Electrochemistry education of future researchers is crucial if we are to decarbonise economies and reach targets for net zero, and this arguably begins with education in electrochemistry within undergraduate degrees. This paper reviews the teaching of electrochemistry in UK universities at the undergraduate degree level. We review where and how electrochemical concepts are introduced into chemistry, chemical engineering and materials science programmes. We provide some motivation for this review, which was stimulated by discussions from a workshop on the ‘Future of Fundamental Electrochemistry Research in the UK’, held in 2022. We summarise briefly how consensus on UK degree programme course content has been reached and inconsistencies that remain. Electrochemistry curriculum content from a convenience sample of UK universities, and disciplines, has been collected and is summarised, with a reflection on some trends. Finally, we present some implications for policy. A roadmap is suggested to ensure that the teaching of electrochemical fundamentals is addressed in the curriculum at an appropriate level to underpin the many technically relevant applications of electrochemistry that graduates will encounter in their further education or employment
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