Testing data types implementations from algebraic specifications

Algebraic specifications of data types provide a natural basis for testing data types implementations. In this framework, the conformance relation is based on the satisfaction of axioms. This makes it possible to formally state the fundamental concepts of testing: exhaustive test set, testability hypotheses, oracle. Various criteria for selecting finite test sets have been proposed. They depend on the form of the axioms, and on the possibilities of observation of the implementation under test. This last point is related to the well-known oracle problem. As the main interest of algebraic specifications is data type abstraction, testing a concrete implementation raises the issue of the gap between the abstract description and the concrete representation. The observational semantics of algebraic specifications bring solutions on the basis of the so-called observable contexts. After a description of testing methods based on algebraic specifications, the chapter gives a brief presentation of some tools and case studies, and presents some applications to other formal methods involving datatypes

Estimation of settling velocities

International audienceThis paper deals with settling velocities estimation, which is of major importance as settling velocities estimation is a prerequisite for properly dimensioning settling ranks. Several measurement procedures are presented and analyzed here. A general framework for identification which includes modelisation of the settlers and identification techniques is developed here-in. In this paper, we demonstrate that for a parametric set of settling density functions ?(dv) = S(i)(N)= (l)?(i)?(i)(dv) the mathematical relation between the measures M(t(i))(i) = l,N and the unknown quantities (0(i))(i) = (l,N) take the following linear form M(t(i)) = S(k)(N) = (l)0(k)?RØx(t(i),v)?(k)(dv). This relation makes it possible to have access to statistical errors in settling velocity estimates (0(i)) in assuming that a statistical model of measurement errors (M(t(i))) exists. The consequences of the choice of sampling times (t(i))(i) = (l,N) on the quality of the estimation are also investigated.This paper deals with settling velocities estimation, which is of major importance as settling velocities estimation is a prerequisite for properly dimensioning settling tanks. Several measurement procedures are presented and analyzed here. A general framework for identification which includes modelization of the settlers and identification techniques is developed here-in. In this paper, we demonstrate that for a parametric set of settling density functions ?(dv) = ?i = 1N?i?i(dv) the mathematical relation between the measures M(ti)i = 1,N and the unknown quantities (?i)i = 1,N take the following linear form M(ti) = ?k = 1N?k?Rfx(ti, v)?k(dv). This relation makes it possible to have access to statistical errors in settling velocity estimates (?i) in assuming that a statistical model of measurement errors (M(ti)) exists. The consequences of the choice of sampling times (ti)i = 1,N on the quality of the estimation are also investigated

A stochastic approach to modelling solid transport in settling tanks

International audienceDispersion and settling models for suspended solids (SS) in turbulent flow are in the majority of cases Eulerian and deterministic. They simulate SS transport using a convection-diffusion equation. When the diffusion term is supposed not to be zero at the boundary of a settling tank, we show that an alternative (or equivalent) description of the basic convection-diffusion equation for the concentration of suspended solids consists in modelling the particles trajectories as a stochastic diffusion process. This paper has two aims, firstly to present the proposed stochastic approach and secondly to apply this new method to the calculation of a settling tank's efficiency

From Structuring Elements to Structuring Neighborhood Systems

International audienceIn the context of mathematical morphology based on structuring elements to define erosion and dilation, this paper generalizesthe notion of a structuring element to a new setting called structuringneighborhood systems. While a structuring element is often defined as asubset of the space, a structuring neighborhood is a subset of the subsetsof the space. This yields an extended definition of erosion; dilation canbe obtained as well by a duality principle. With respect to the classicalframework, this extension is sound in many ways. It is also strictly moreexpressive, for any structuring element can be represented as a structuring neighborhood but the converse is not true. A direct applicationof this framework is to generalize modal morpho-logic to a topologicalsetting

Integration Testing from Structured First-Order Specifications via Deduction Modulo

Abstract. Testing from first-order specifications has mainly been studied for flat specifications, that are specifications of a single software module. However, the specifications of large software systems are generally built out of small specifications of individual modules, by enriching their union. The aim of integration testing is to test the composition of modules assuming that they have previously been verified, i.e. assuming their correctness. One of the main method for the selection of test cases from first-order specifications, called axiom unfolding, is based on a proof search for the different instances of the property to be tested, thus allowing the coverage of this property. The idea here is to use deduction modulo as a proof system for structured first-order specifications in the context of integration testing, so as to take advantage of the knowledge of the correctness of the individual modules. Testing is a very common practice in the software validation process. The principle of testing is to execute the software system on a subset of its possible inputs in order to detect failures. A failure is detected if the system behaves in a non-conformant wa

Analysis of the methods for determining the settling characteristics of sewage and stormwater solids

International audienceIn order to optimise the design and the management of sewer networks and settling tanks, there is a need to determine the settling velocity characteristics of sewage and stormwater solids. Devices and test methods for measuring settling velocities of these solids have been developed. In order to quantify the influence of the experimental procedure on the settling velocity grading curves, we have compared three selected methods (Cergrene, Aston, Camp) when tested with the same sample with the method developed by UFT. The results of the comparative tests indicate that the settling velocities are significantly higher with the UFT test procedure than the other methods. This is mainly explained by the fact that the UFT method takes only settleable solids into account. When the calculations of the four methods are made with the total mass of SS, the study has shown that the settling velocity curves of the same samples are different. The differences vary between the nature of the samples and the test procedures which were compared. The influence of the experimental procedure for separating a sample by settling velocities fractions is demonstrated. In conclusion, we explain the need to develop an international test procedure in order to be able to compare the results.In order to optimize the design and the management of sewer networks and settling tanks, there is a need to determine the settling velocity characteristics of sewage and stormwater solids. Devices and test methods for measuring settling velocities of these solids have been developed (Chebbo, 1992), (Michelbach and Wohrle, 1993) and (Tyack et al., 1993). In order to quantify the influence of the experimental procedure on the settling velocity grading curves, we have compared three selected methods (Cergrene, Aston, Camp) when tested with the same sample with the method developed by UFT (Michelbach and Wohrle, 1993). The results of the comparative tests indicate that the settling velocities are significantly higher with the UFT test procedure than the other methods. This is mainly explained by the fact that the UFT method takes only settleable solids into account. When the calculations of the four methods are made with the total mass of SS, the study has shown that the settling velocity curves of the same samples are different. The differences vary between the nature of the samples and the test procedures which were compared. The influence of the experimental procedure for separating a sample by settling velocities fractions is demonstrated. In conclusion, we explain the need to develop an international test procedure in order to be able to compare the results

Methods for determining the settling velocity profiles of solids in storm sewage

International audienceRecently, research has shown that a settling process is an efficient treatment for the removal of suspended solids from storm sewage. In order to design settling tanks, there is a need to determine the settling velocity characteristics of these solids. Devices and test methods for measuring settling velocities of solids in storm sewage have been developed by researchers. A literature review has revealed that the settling velocity profiles obtained with some methods are very different. In order to explain why the results are different and to quantify the influence of the experimental procedure on the settling velocity grading curves, we have compared the selected methods when tested with the same sample and we have studied the effects of the conservation of the sample before the test, of the concentration of solids in the device and of the nature of the water on the settling velocity profiles. The results of the comparative tests indicate that the settling velocities are significantly lower with both the Cergrene and Aston methods than with the UFT test procedure. Moreover, the study has shown that the settling characteristics of solids change with time, that the use of sewage liquor rather than demineralised water or drinking water can change the results of the measurement and that the higher the concentration of solids, the greater the velocity of settled particles

La co-conception en Living Lab santé et autonomie 1 - Concepts, méthodes et outils

International audienceLa période récente a vu la multiplication des « Living Labs » , structures visant à faire travailler ensemble des acteurs différents dans leurs compétences et objectifs individuels, y compris l’usager final, pour concevoir, développer, mettre en oeuvre et évaluer des solutions innovantes.Ce livre présente un travail associant les acteurs de terrain et académiques sur la co-conception dans les Living Labs santé et autonomie (LLSA). Il précise des lignes communes et des bonnes pratiques malgré leur diversité. Cette connaissance des LLSA permet de comprendre leur capacité à soutenir un développement efficient de cette forme de conception pour les acteurs de la santé et de l’autonomie, l’industrie et les investisseurs.La co-conception en Living Lab santé et autonomie 1 donne ainsi une meilleure visibilité et lisibilité de ces nouveaux acteurs. Ce premier ouvrage examine les concepts, méthodes et outils des LLSA. Il s’appuie sur leur expérience et le regard d’experts pour éclairer leur mise en oeuvre. Le coordonnateur - Ingénieur général des Mines, docteur en sciences de gestion, cofondateur du forum LLSA, Robert Picard est également référent santé du conseil général de l'économie au ministère de l'Economie. Il est l'auteur de nombreux rapports sur la valeur des technologies en santé

La co-conception en Living Lab santé et autonomie 1 - Concepts, méthodes et outils

International audienceLa période récente a vu la multiplication des « Living Labs » , structures visant à faire travailler ensemble des acteurs différents dans leurs compétences et objectifs individuels, y compris l’usager final, pour concevoir, développer, mettre en oeuvre et évaluer des solutions innovantes.Ce livre présente un travail associant les acteurs de terrain et académiques sur la co-conception dans les Living Labs santé et autonomie (LLSA). Il précise des lignes communes et des bonnes pratiques malgré leur diversité. Cette connaissance des LLSA permet de comprendre leur capacité à soutenir un développement efficient de cette forme de conception pour les acteurs de la santé et de l’autonomie, l’industrie et les investisseurs.La co-conception en Living Lab santé et autonomie 1 donne ainsi une meilleure visibilité et lisibilité de ces nouveaux acteurs. Ce premier ouvrage examine les concepts, méthodes et outils des LLSA. Il s’appuie sur leur expérience et le regard d’experts pour éclairer leur mise en oeuvre. Le coordonnateur - Ingénieur général des Mines, docteur en sciences de gestion, cofondateur du forum LLSA, Robert Picard est également référent santé du conseil général de l'économie au ministère de l'Economie. Il est l'auteur de nombreux rapports sur la valeur des technologies en santé