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A simple way to unify multicriteria decision analysis (MCDA) and stochastic multicriteria acceptability analysis (SMAA) using a Dirichlet distribution in benefit-risk assessment
No full textQuantitative methodologies have been proposed to support decision making in drug development and monitoring. In particular, multicriteria decision analysis (MCDA) and stochastic multicriteria acceptability analysis (SMAA) are useful tools to assess the benefit-risk ratio of medicines according to the performances of the treatments on several criteria, accounting for the preferences of the decision makers regarding the relative importance of these criteria. However, even in its probabilistic form, MCDA requires the exact elicitations of the weights of the criteria by the decision makers, which may be difficult to achieve in practice. SMAA allows for more flexibility and can be used with unknown or partially known preferences, but it is less popular due to its increased complexity and the high degree of uncertainty in its results. In this paper, we propose a simple model as a generalization of MCDA and SMAA, by applying a Dirichlet distribution to the weights of the criteria and by making its parameters vary. This unique model permits to fit both MCDA and SMAA, and allows for a more extended exploration of the benefit-risk assessment of treatments. The precision of its results depends on the precision parameter of the Dirichlet distribution, which could be naturally interpreted as the strength of confidence of the decision makers in their elicitation of preferences
Catalytic combustion of residual methane on alumina monoliths and open cell foams coated with Pd/Co3O4
No full textThe reactivity of a catalytic layer consisting of 3 wt.% of Pd/Co3O4 over an alumina monolith (100 cpsi, diameter 0.9 cm, length 3 cm) and two alumina open cell foams (30 and 45 ppi, diameter 0.9 cm, length 3 cm) in the oxidation of residual methane in lean conditions was investigated. The ceramic structures were coated via solution combustion synthesis (Co3O4) and wetness impregnation (Pd). The catalytic reactivity of the catalysts coated on the structured supports was assessed in a gas mixture containing 0.5 or 1 vol.% of methane at different weight hourly space velocities (WHSV, 30 and 60 NL h-1 gcat-1). Moreover, the prepared structured catalysts were characterized by measuring the pressure drop and determining the volumetric heat transfer coefficients. Both the WHSV and the structure of the support influenced the catalytic activity. In general, open cell foams coated with Pd/Co3O4 show superior catalytic activity than the coated monolith
HAIT: Heap Analyzer with Input Tracing
No full textHeap exploits are one of the most advanced, complex and frequent types of attack. Over the years, many effective techniques have been developed to mitigate them, such as data execution prevention, address space layout randomization and canaries. However, if both knowledge and control of the memory allocation are available, heap spraying and other attacks are still feasible. This paper presents HAIT, a memory profiler that records critical operations on the heap and shows them graphically in a clear and comprehensible format. A prototype was implemented on top of Triton, a framework for dynamic binary analysis. The experimental evaluation demonstrates that HAIT can help identifying the essential information needed to carry out heap exploits, providing valuable knowledge for an effective attack
Investigation on the conversion of rapeseed oil via supercritical ethanol condition in the presence of a heterogeneous catalyst
No full textThis article presents an environmentally friendly approach for the conversion of rapeseed oil via supercritical ethanol condition, with and without the presence of a solid catalyst, to produce biodiesel. The experiment was conducted in a batch reactor at various temperatures, reaction times, and ethanol to oil molar ratios. The evolution of process was followed by high performance liquid chromatography to determine accurately and quickly the content of final reaction mixture in a single analysis. The results show that the highest biodiesel yields of 93% (with ZnO) and 88% (with CaO) were obtained after the reaction time of 60 min at a temperature of 270°C. This process has high potential in minimizing the production cost of biodiesel due to its simplicity and technical advantage
A new hybrid procedure for the definition of seismic vulnerability in Mediterranean cross-border urban areas
No full textAssessment of seismic vulnerability of urban areas provides fundamental information for activities of planning and management of emergencies. The main difficulty encountered when extending vulnerability evaluations to urban contexts is the definition of a framework of assessment appropriate for the specific characteristics of the site and providing reliable results with a reasonable duration of surveys and post-processing of data. The paper proposes a new procedure merging different typologies of information recognized on the territories investigated and for this reason called ‘‘hybrid.'' Knowledge of historical events influencing urban evolution and analysis of recurrent building technologies are used to evaluate the vulnerability indexes of buildings and building stocks. On the other hand, a vulnerability model is calibrated by means of experimental and numerical investigations on prototype buildings representative of the most recurrent typologies. In the final framework, the vulnerability index, calculated through simplified assessment forms, is linked to the seismic intensity expressed by the peak ground acceleration and associated with an index of damage expressing the economical loss. The procedure has been tested on the urban center of Lampedusa island (Italy) providing as the output vulnerability index maps, vulnerability curves, critical PGA maps, and estimation of the economical damage associated with different earthquake scenarios. The application of the procedure can be suitably repeated for medium-to-small urban areas, typically recurring in the Mediterranean by carrying out each time a recalibration of the vulnerability mode
Online convex optimization meets sparsity
No full textTracking time-varying sparse signals is a recent problem with widespread applications. Techniques derived from compressed sensing, Lasso, and Kalman filtering have been proposed in the literature, which mainly present two drawbacks: the prior knowledge of specific evolution models and the lack of theoretical guarantees. In this work, we propose a new perspective on the problem, based on the theory on online convex optimization, which has been developed in the machine learning community. We exploit a strongly convex model, and we develop online algorithms, for which we are able to provide a dynamic regret analysis. A few simulations that support the theoretical results are finally presented
A novel geometric formula for predicting contractile force in McKibben pneumatic muscles
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Charged-particle multiplicities in proton-proton collisions at √s=0.9 to 8 TeV
No full textA detailed study of pseudorapidity densities and multiplicity distributions of primary charged particles produced in proton-proton collisions, atv root s = 0.9, 2.36, 2.76, 7 and 8 TeV, in the pseudorapidity range vertical bar n vertical bar< 2, was carried out using the ALICE detector. Measurements were obtained for three event classes: inelastic, non-single diffractive and events with at least one charged particle in the pseudorapidity interval vertical bar n vertical bar<1. The use of an improved track-counting algorithm combined with ALICE's measurements of diffractive processes allows a higher precision compared to our previous publications. A KNO scaling study was performed in the pseudorapidity intervals vertical bar n vertical bar< 0.5, 1.0 and 1.5. The data are compared to other experimental results and to models as implemented in Monte Carlo event generators PHOJET and recent tunes of PYTHIA6, PYTHIA8 and EPOS