Méthodes et outils pour l'aide à la conception et à la vérification du rendu graphique des systèmes interactifs

La conception de représentations graphiques dédiées à des systèmes interactifs critiques est complexe. Dans cette thèse, nous proposons en premier lieu une étude approfondie des problèmes perceptifs spécifiques aux rendus graphiques au travers de trois études expérimentales. Nous présentons ensuite une analyse de l'activité à laquelle se livrent les concepteurs d'interfaces critiques. À partir de ces analyses, nous proposons une démarche d'aide à la conception et à la vérification des rendus graphiques répondant aux besoins spécifiques des concepteurs. Cette démarche facilite l'exploration visuelle des solutions, ainsi que la mise en rapport de hiérarchies fonctionnelles avec des hiérarchies visuelles. Elle supporte une approche de conception itérative, centrée utilisateur et visant un accompagnement sur toute la durée de vie des systèmes. Nous proposons pour finir d'instrumenter cette démarche à l'aide d'outils interactifs, dont nous illustrons l'utilisation au travers d'études de cas lié à l'aéronautique (ATC).Graphical representations are used in numerous field of activity as a way to convey information from an interactive system to its users. In some of these fields, the representation quality is vital: indeed, if users (like pilots or air-traffic controllers) have a bad perception of information, the consequences can be tragic. Graphical design and specification of such representations are complex because of the great amount and the diversity of graphical parameters to handle, because of the perceptual interactions between these parameters, and because of the need to manage multidisciplinary knowledge. We claim that these difficulties come also from a lack of tools and methods, which could enable a precise specification of graphical needs. The first part of our work deals with three experimental studies aimed at understanding in a deeper way the perceptive problems linked to the graphical rendering of interactive systems. Then, we expose an analysis of how the graphical designers confront critical interfaces design. Based on these analyses, we propose an approach responding to the specific designer's needs for their activity of designing and verifying the graphical rendering. This approach enables an easier visual exploration of solutions and an easier connection between functional and visual hierarchies. This is a user centered design and iterative approach that aims to follow a system during all its lifetime. Finally, we propose interactive tools that support this approach and we illustrate them with case studies

Conception instrumentée du rendu graphique des interfaces

International audienceWe propose to define the activity of graphical rendering design, which aims at maximizing the display quality of the image components. Overlooked in most design methods, this activity is essential for the success of a design project and for the validation of interfaces of critical systems. As such, it is pluri-disciplinary: graphical design (design, infovis), evaluation (experimental psychology), influence from hardware and software technologies (computer science), design methodology (design rationale, maintenance, computer science). In this paper, we detail the activity of graphical rendering design of HMI, by identifying its main dimensions. We also present a tool that instruments it: we describe its main functionalities, as well as the methods allowing to achieve the activity. Finally, we discuss about the benefits of inter disciplinary instrumentation during the design process

Génération et placement de couleurs sur une vue de type métro

International audienceThe schematic views for metro maps are used to maximize the transmision of relevant information (lines, metro stops) of network visualization. Automatic generation of metro maps focus primarily on the physical structure of the network, but little on the choice of colors which is an accurate visual discrimination. In this article, we propose to invesigate the generation and placement of colors to be assigned to lines of a network. The first step is to find as many colors as lines of the network. These colors must be perceptually as distant as possible, and available in the vocabulary of colors. The second step is to place these colors so that the closest lines have the more distant color. The positioning of colors is a NP-complete problem, thus we use a meta-heuristic approach to solve it. To validate our method, we apply it to the field of air traffic control with the maps of Flight Routes

Effets des paramètres graphiques sur la perception visuelle : experimentations sur la forme, la surface, l'orientation des objets et la définition des écrans

International audienceUser interfaces of critical systems, such as air traffic control displays, use graphical objects to code for an ever increasing amount of information. This evolution brings forth concerns about the detection and identification of the displayed objects, in particular for small size objects. First, graphic properties of the interface should include some knowledge about the interplay between colour, shape and size interactions, and the visual perception. Second, the redesign of any interactive system should take into account the particularities of the evolving software and hardware display technology (pixel size and structure, for example) in order to preserve crucial aspects of the initial visual display. The two experiments described in this paper are aiming towards building a more systematic knowledge of graphic properties interactions per se, and their changes as a function of display technologies. More precisely, we examined the effect of the object size, shape and luminosity, as well as its contrast with the background. Results show that object perception is dependent upon its size, its contrast with the background and the overall luminosity of the background. Furthermore, for small size objects, interactions between pixel luminosities and pixel arrangement greatly influence their perception by the human eye

Firms as adaptive organizations : the case of Australian trading banks

The conventional accounting notion of ‘going concern’ — that a firm will continue its business operations in the same manner indefinitely — has underpinned accounting practice for over one hundred years. This idea has provided a rationale for spreading costs over accounting periods and for deferring costs as assets in balance sheets. An alternative idea that is widely regarded as reliable in the literatures of economics and deliberate action is that firms continually adapt to changes in market and economic conditions. That is economic behaviour. The implications of that view of a firm for accounting have been systematically explored by Chambers (1966). While not examining those particular implications, many other accounting theorists have been critical of the conventional accounting idea of \u27going concern\u27 and of its impact on accounting practice. The two notions of ‘going concern’ - as static or adaptive enterprises - are examined by referring to the business operations of the four major Australian trading banks over the period 1983-1991. Banks were selected because they are commonly thought to be particularly ‘conservative’ organizations. The period 1983—1991 was chosen because it covers the era of deregulation of the Australian financial system. The evidence adduced by this study indicates that the Australian trading banks have continually adapted their organizational structures and business operations in the light of changes in technology, markets for financial services, government policies and domestic and global economic conditions. Illustrations of adaptive behaviour by banks ate drawn from their normal operating procedures such as the provision of products and services, loan services, acquisitions, sale of property, non-core banking operations and international banking. It is argued on analytical grounds that the cost basis of accounting does not yield financial statements that provide factual and up-to-date information about the financial capacity of firms to pay their debts and to continue trading generally; that is, to be going concerns. At any time, those financial capacities are determined by the amount of money commanded by a firm, including the money\u27s worth of its assets, and by its level of debt. It is concluded on empirical grounds that the Australian trading banks, at least, are adaptive entities

An automatic generation of metro-like maps to display flight routes for air traffic controllers: structure and color optimization

International audienceAircraft must follow strict Air Traffic Control (ATC) rules. One of these rules is that aircraft have to fly over pre-defined Flight Routes (FR). Current ATC visualizations do not display FRs because they are numerous and run into each other, and thus spoil the visualization. The schematic views for metro maps are used to maximize the transmission of relevant information (lines, metro stops) of network visualization. In this paper, we will focus on two different issues. First, we show how we transposed mathematical constraints used to produce metro maps into the specific field of ATC. The view produced is a context compatible, 2D picture of a schematic maps view for Air Traffic Control. Second, we propose to investigate the generation and placement of colors to be assigned to lines of the network. The first step is to find as many colors as lines of the network. These colors must be perceptually as distinct as possible, and available in the vocabulary of colors. The second step is to solve the NP-complete problem of the optimal assignment of these colors so that close lines have the most perceptively distant color. Finally, we assess the map produced through experimentation to validate its quality

RNA silencing in the dermatophyte Microsporum canis

Dermatomycoses caused by Microsporum canis are frequent in domestic animals and easily transmissible to humans. Several proteases secreted by this fungus were identified as potential virulence factors, but the construction of deficient strains is required to investigate their role in the pathogenesis of the disease. Using target genes encoding two of these proteases, a first evaluation of the utility of RNA-mediated silencing as a reverse genetic tool in dermatophytes was carried out. SUB3 and DPPIV, respectively coding for a subtilisin and a dipeptidyl peptidase, were both down-regulated, by means of two plasmid constructs designed to express an RNA hairpin that corresponds to part of their respective sequence. The degree of attenuation was evaluated by enzymatic assay of the transformants culture supernatants, and by real-time reverse transcriptase-polymerase chain reaction. Enzymatic activities and expression levels varied from less than 5% to 100% of that of control transformants obtained with plasmid without hairpin inserts. Inhibition was globally more efficient for SUB3 than for DPPIV. These results show that RNA silencing can be used for functional genomics in M. canis, and particularly to circumvent the limits and technical difficulties of conventional disruption method

RNA silencing in the dermatophyte Microsporum canis

Dermatomycoses caused by Microsporum canis are frequent in domestic animals and easily transmissible to humans. Several proteases secreted by this fungus were identified as potential virulence factors, but the construction of deficient strains is required to investigate their role in the pathogenesis of the disease. Using target genes encoding two of these proteases, a first evaluation of the utility of RNA-mediated silencing as a reverse genetic tool in dermatophytes was carried out. SUB3 and DPPIV, respectively coding for a subtilisin and a dipeptidyl peptidase, were both down-regulated, by means of two plasmid constructs designed to express an RNA hairpin that corresponds to part of their respective sequence. The degree of attenuation was evaluated by enzymatic assay of the transformants culture supernatants, and by real-time reverse transcriptase-polymerase chain reaction. Enzymatic activities and expression levels varied from less than 5% to 100% of that of control transformants obtained with plasmid without hairpin inserts. Inhibition was globally more efficient for SUB3 than for DPPIV. These results show that RNA silencing can be used for functional genomics in M. canis, and particularly to circumvent the limits and technical difficulties of conventional disruption method

Building Pathways for Empowering User Toward Prosumer Behaviour. The Design for Experience with the Prosumer Empowerment Concentric Model

Acting as prosumers can help the transition towardlow carbon and circular economies. This paper discusses whatcan be defined as “prosumer behaviours” and proposes aninnovative approach that fosters users in adopting dailyvirtuous experiences about energy production andconsumption. Such experiences are based on smart interfacesas they emerge from complex socio-technical systems thatcombined ICT devices, smart grids and user-centred toolscreated to empower users and facilitate the emergence of apositive intelligence. The Prosumer Empowerment Concentric(PEC) Model is presented here as an integrative vision tosupport the emergence of prosumer behaviours andperspectives are outlined via an interregional project thatproposes to experiment the PEC model in households andcitizen energy cooperatives

Evaluation of Antioxidant Compounds and Total Sugar Content in a Nectarine [Prunus persica (L.) Batsch] Progeny

Epidemiological studies suggest that consumption of fruit rich in phenolic compounds is associated with health-protective effects due to their antioxidant properties. For these reasons quality evaluation has become an important issue in fruit industry and in breeding programs. Phytochemical traits such as total phenolics, flavonoids, anthocyanins, L-ascorbic acid, sugar content and relative antioxidant capacity (RAC) were analyzed over four years in flesh fruit of an F1 population “Venus” × “Big Top” nectarines. Other traits such as harvesting date, yield, fruit weight, firmness, soluble solids concentration (SSC), pH, titratable acidity (TA) and ripening index (RI) were also determined in the progeny. Results showed high variability among genotypes for all analyzed traits. Total phenolics and flavonoids showed significant positive correlations with RAC implying that both are important antioxidant bioactive compounds in peaches. We found genotypes with enhanced antioxidant capacity and a better performance than progenitors, and in consequence the best marketability