Anodic film studies on nickel under high rate transpassive dissolution conditions

Coulometry and Auger Electron Spectroscopy (AES) were employed to study thickness and composition of anodic films formed on nickel under high rate transpassive dissolution conditions. Nickel anodes were polarized at constant current densities up to 30 A/cm² in alkaline nitrate electrolytes of different nitrate and hydroxyl ion concentration using a flow channel cell with a constant electrolyte flow velocity of 10m/sec. Results show that with increasing current density film thickness goes through a maximum. Nitrogen is detected at the apparent film metal interface in the current region where metal dissolution occurs. No correlation between anodic film thickness and dissolution efficiency is found. The data, together with previous observations, suggest that high rate transpassive dissolution takes place from film free sites.     

Wearable cognitive assistants in a factory setting: a critical review of a promising way of enhancing cognitive performance and well-being

Cognition, Technology & Work - Rapid technological innovations are constantly influencing the complexification and automatization of the work lines pushing human operators to use diverse...     

Inter-MAC Green Path Selection for Heterogeneous Networks

Gigabit home networks represent a key technology to make the Future Internet success a reality. Consumers will require networks to be simple to install, without the need of any new wire and with green consideration. To make this network ubiquitous, seamless and robust, a technology independent MAC layer will ensure its global control and provide connectivities to any number of devices the user wishes to connect to it in any room. In order to make this vision comes true, substantial progress is required in the fields of protocol design and in systems architectures. For this goal, we introduce a new convergence layer denoted inter-MAC, which provides a common infrastructure to the home network, Among the inter-MAC functionalities, we focused the interest on the path selection mechanism including the green aspect. To improve quality of service, reduce energy consumption and radiofrequency devices number, we define a new path selection protocol based on several metrics. We present some preliminary results obtained on an experimental test bed.     

Finding a dominating set on bipartite graphs

Finding a dominating set of minimum cardinality is an NP-hard graph problem, even when the graph is bipartite. In this paper we are interested in solving the problem on graphs having a large independent set. Given a graph G with an independent set of size z, we show that the problem can be solved in time O^∗(²n−z), where n is the number of vertices of G. As a consequence, our algorithm is able to solve the dominating set problem on bipartite graphs in time O^∗(²n/2). Another implication is an algorithm for general graphs whose running time is O(n^1.7088).     

Topological Dynamics of Cellular Automata: Dimension Matters

Topological dynamics of cellular automata (CA), inherited from classical dynamical systems theory, has been essentially studied in dimension 1. This paper focuses on higher dimensional CA and aims at showing that the situation is different and more complex starting from dimension 2. The main results are the existence of non sensitive CA without equicontinuous points, the non-recursivity of sensitivity constants, the existence of CA having only non-recursive equicontinuous points and the existence of CA having only countably many equicontinuous points. They all show a difference between dimension 1 and higher dimensions. Thanks to these new constructions, we also extend undecidability results concerning topological classification previously obtained in the 1D case. Finally, we show that the set of sensitive CA is only $\varPi _{2}^{0}$ in dimension 1, but becomes $\varSigma _{3}^{0}$ -hard for dimension 3.     

Randomness on Computable Probability Spaces—A Dynamical Point of View

We extend the notion of randomness (in the version introduced by Schnorr) to computable probability spaces and compare it to a dynamical notion of randomness: typicality. Roughly, a point is typical for some dynamic, if it follows the statistical behavior of the system (Birkhoff’s pointwise ergodic theorem). We prove that a point is Schnorr random if and only if it is typical for every mixing computable dynamics. To prove the result we develop some tools for the theory of computable probability spaces (for example, morphisms) that are expected to have other applications.     

Deformation Transfer to Multi‐Component Objects

We present a simple and effective algorithm to transfer deformation between surface meshes with multiple components. The algorithm automatically computes spatial relationships between components of the target object, builds correspondences between source and target, and finally transfers deformation of the source onto the target while preserving cohesion between the target's components. We demonstrate the versatility of our approach on various complex models.     

Assessment of Digital Elevation Model (DEM) aggregation methods for hydrological modeling: Lake Chad basin,Africa

Digital Elevation Models (DEMs) are used to compute the hydro-geomorphological variables required by distributed hydrological models. However, the resolution of the most precise DEMs is too fine to run these models over regional watersheds. DEMs therefore need to be aggregated to coarser resolutions, affecting both the representation of the land surface and the hydrological simulations. In the present paper, six algorithms (mean, median, mode, nearest neighbour, maximum and minimum) are used to aggregate the Shuttle Radar Topography Mission (SRTM) DEM from 3″ (90 m) to 5′ (10 km) in order to simulate the water balance of the Lake Chad basin (2.5 Mkm²). Each of these methods is assessed with respect to selected hydro-geomorphological properties that influence Terrestrial Hydrology Model with Biogeochemistry (THMB) simulations, namely the drainage network, the Lake Chad bottom topography and the floodplain extent.The results show that mean and median methods produce a smoother representation of the topography. This smoothing involves the removing of the depressions governing the floodplain dynamics (floodplain area<5000 km²) but it eliminates the spikes and wells responsible for deviations regarding the drainage network. By contrast, using other aggregation methods, a rougher relief representation enables the simulation of a higher floodplain area (>14,000 km² with the maximum or nearest neighbour) but results in anomalies concerning the drainage network. An aggregation procedure based on a variographic analysis of the SRTM data is therefore suggested. This consists of preliminary filtering of the 3″ DEM in order to smooth spikes and wells, then resampling to 5′ via the nearest neighbour method so as to preserve the representation of depressions. With the resulting DEM, the drainage network, the Lake Chad bathymetric curves and the simulated floodplain hydrology are consistent with the observations (3% underestimation for simulated evaporation volumes).