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The paper presents a universal architectural pattern and an associated specification method that can be applied in the design of robot control systems. The approach describes the system in terms of embodied agents and proposes a multi-step decomposition enabling precise definition of their inner structure and operation. An embodied agent is decomposed into effectors, receptors, both real and virtual, and a control subsystem. Those entities communicate through communication buffers. The activities of those entities are governed by FSMs that invoke behaviours formulated in terms of transition functions taking as arguments the contents of input buffers and producing the values inserted into output buffers. The method is exemplified by applying it to the design of a control system of a robot executing one of the most important tasks for a service robot, i.e. picking up, by a position-force controlled robot, an object located using an RGB-D image acquired from a Kinect. Moreover in order to substantiate the universality of the presented approach we present how classical, known from the literature, robotic architectures can be expressed as systems composed of one or more embodied agents. [ABSTRACT FROM AUTHOR]

The paper presents a universal architectural pattern and an associated specification method that can be applied in the design of robot control systems. The approach describes the system in terms of embodied agents and proposes a multi-step decomposition enabling precise definition of their inner structure and operation. An embodied agent is decomposed into effectors, receptors, both real and virtual, and a control subsystem. Those entities communicate through communication buffers. The activities of those entities are governed by FSMs that invoke behaviours formulated in terms of transition functions taking as arguments the contents of input buffers and producing the values inserted into output buffers. The method is exemplified by applying it to the design of a control system of a robot executing one of the most important tasks for a service robot, i.e. picking up, by a position-force controlled robot, an object located using an RGB-D image acquired from a Kinect. Moreover in order to substantiate the universality of the presented approach we present how classical, known from the literature, robotic architectures can be expressed as systems composed of one or more embodied agents. [ABSTRACT FROM AUTHOR]

Retention-detention basins are important structures for managing stormwater. However, their long-term operation raises the problem of managing the sediments they accumulate. Potential uses for such sediments have been envisaged, but each sediment must be characterised beforehand to verify its harmlessness. In this paper we address this issue through the development of a battery of bioassays specifically adapted to such sediments. We tested the method on samples taken from four retention basins in the region of Lyon (France). This battery focuses on the toxic effects linked to both the solid phase (ostracod and Microtox® solid-phase tests) and the liquid-phase (interstitial water) of sediments (rotifer and Microtox® liquid-phase tests). The results obtained permit the sorting of sediments presenting little toxicity, and which could therefore be potentially exploitable, from those from more polluted areas presenting higher toxicity that limits their use. [ABSTRACT FROM AUTHOR]

Infiltration basins are widely used in urban environments as a technique for managing and reducing the volume of stormwater. These basins can be spontaneously colonized by wild plants, which can be used as bioindicators of edaphic characteristics. As the basins are anthropogenic environments, the description of plant biodiversity allows the determination of which species colonize such environments and identification of the relationships between plants, basin type and operation. Nineteen infiltration basins were selected according to their catchment types (industrial, urban, agricultural). The dominant species were identified and sampled. Rumex sp., Taraxacum sp. and Artemisia sp. are the three types most represented (88, 61 and 55% respectively of the basins studied). Their families and their respective orders are those most commonly found (Caryophyllales, Asterales and Polygonaceae, Asteraceae). Poaceae is the family grouping with the largest number of different species (11). Although each species occupies only 1 or 2 basins, plants of this family occupy 61% of the basins. Although the catchment characteristics of the 19 basins do not play a direct role in the diversity of plant families, they can influence the presence or absence of certain species. Thus, these plants can be used as bio-indicators of basin soil and operating characteristics, such as sediment depths, inundation frequency and duration. [ABSTRACT FROM AUTHOR]

Abstract: Infiltration basins are part of the best management practices. They are aimed at infiltrating stormwater to prevent additional collection and treatment through rainwater systems. In the suburbs of Lyon (France), many of these infiltration basins were built over fluvio-glacial deposit. These basins have been the subject of research programs on vadose zone flow and fate of pollutants. This study focuses on the impact of the heterogeneity of the fluvio-glacial deposit on both flow pattern and solute transfer. A proper geological and sedimentological description is first proposed to characterize the efficient water transfer properties of the fluvio-glacial deposit at the work scale (1ha). The local geological and sedimentological architecture of the deposit and its lithofacies were investigated locally through trenches using both particle size analysis and sedimentological approach. This information was extended to the whole work by combining several geophysical techniques, i.e. GPR, electric resistivity and seismic refraction tomography (data not shown). Then water infiltration experiments were performed on each lithofacies to derive the hydrodynamic properties through BEST algorithm (Beerkan estimation of Soil Transfer properties), leading to the corresponding hydrofacies. In addition, soil-column and batch experiments were performed to estimate hydrodispersive parameters by tracer experiments and the geochemical properties of lithofacies for a model pollutant, i.e. copper (Cu). All these data were implemented into Hydrus to model flow and solute transfer through a 2D soil profile with a precise description of the hydrofacies at the basin scale (flow domain 14x2 m2). The results are highly relevant because they emphasize different types of preferential flow due to either the presence of capillary barriers, drainage layers or pipe flow, which may be responsible for the enhancement of pollutant transfer. In particular, they show that sand lenses may play an important role whereas unconnected gravels may have insignificant effect on flow. This methodology may help in understanding the mechanisms which that are responsible for preferential solute transfer. A sensitivity analysis combining the distribution of lithofacies, the soil initial water content and unsaturated hydraulic properties allows bettering understanding the development of preferential flows across the vadose zone underneath the basin. This data is of great interest in terms of the optimization of basin infiltration monitoring. [Copyright &y& Elsevier]

In order to evaluate the historical impact of urban stormwater runoff on a lacustrine environment, eight sediment cores were collected in October 2006 in Lake Bourget (Savoie, France). Sediment samples were analysed for polycyclic aromatic hydrocarbons (PAH) and polychlorobyphenyls (PCB) in order to correlate the vertical profiles of contamination and the evolution of the urbanisation on the watershed for the last 100 years. Overall, we observe that vertical profiles of PCB and PAH concentrations in Lake Bourget are showing a downward trend, probably resulting from the pollution control measures. Concentrations of PCB and PAH measured in surface sediments are approximately 5-10 fold less than maximal concentrations found in the cores. Maximal PAH concentrations were found at the bottom of the cores (~40 cm) which approximately correspond to the beginning of the 20th century. Maximal PCB concentrations measured in cores L5 and L6 are respectively 850 and 790 μg/g dw (dryweight). The peak of PCB corresponds to the maximum of PCB production and consumption in the 1970s. In surface sediments total PCB concentrations range between 47 and 79 μg/kg dw. Those concentrations are particularly high compared to other values measured in lake sediments and highlight the problem of a local source of PCB contamination in the watershed. General trends were observed, yet the part of urban stormwater runoff in the total contamination could not be determined. [ABSTRACT FROM AUTHOR]

Purpose – This paper seeks to develop universal software (a programming framework) enabling the implementation of service robot controllers. The software should distinguish the hardware-oriented part of the system from the task-oriented one. Moreover, force, vision as well as other sensors should be taken into account. Multi-effector systems have to be considered. Design/methodology/approach – The robot programming framework MRROC++ has been implemented as a hierarchical structure composed of processes, potentially consisting of threads. All of the software is written in an object-oriented manner using C++ and is supervised by a QNX real-time operating system. The framework has been verified on several systems executing diverse tasks. Here, a Rubik's cube puzzle-solving system, consisting of two arms and utilizing force control and visual servos, is presented. Findings – The presented framework is well suited to tasks requiring two-handed manipulation with force sensing, visual servoing and online construction of plans of actions. The Rubik's cube puzzle is a reasonable initial benchmark for validation of fundamental service robot capabilities. It requires force sensing and sight coupled with two-handed manipulation and logical reasoning, as do the majority of service tasks. Owing to the use of force sensing during manipulation, jamming of the faces has always been avoided; however, visual servoing could only cope with slow handing over of the cube due to the volume of computations associated with vision processing. Research limitations/implications – The proposed software structure does not limit the implementation of service robot controllers. However, some of the specific algorithms used for the solution of the benchmark task (i.e. Rubik's cube puzzle) need to be less time-consuming. Practical implications – The MRROC++ robot programming framework can be applied to the implementation of diverse robot controllers executing complex service tasks. Originality/value – A demanding benchmark task for service robots has been formulated. This task, as well as many others, has been used to validate the MRROC++ robot programming framework which significantly facilitates the implementation of diverse robot systems. [ABSTRACT FROM AUTHOR]

After the proof of a not very known refinement of the Noether Normalization Theorem, we obtain two sharp degree bounds for the geometric degree of a dominating morphism of irreducible affine algebraic varieties and for the degree of the components of the inverse of an isomorphism of such varieties, generalizing by this way the well-known Gabber bound for automorphisms of affine spaces. [ABSTRACT FROM AUTHOR]

Geotextiles are fibrous materials increasingly employed for the design of infiltration basins. However, their influence on the transfer of contaminants carried by stormwater has not been fully investigated. This study, based on column leaching experiments, aims at showing the effect of geotextiles on the transfer of three heavy metals (Zn, Pb and Cd) in a reactive soil (simulating an infiltration basin at laboratory scale). This effect depends on several factors, such as type of geotextile, hydric conditions (geotextile water content), hydraulic conditions (flow-rates) and the number of geotextiles installed. In all cases, geotextiles influence heavy metal retention by modifying flow and thus regulating contact between these metals and the reactive soil. [ABSTRACT FROM AUTHOR]

Although geotextiles are increasingly employed in stormwater infiltration basins, their influence on the flow and transfer of contaminants, such as heavy metals, has not been fully investigated. Leaching column experiments were conducted to characterize the flow and transfer of three heavy metals (zinc, lead, and cadmium) in a calcareous soil with and without geotextiles under steady-state flow and close to saturation for the soil. The influence of geotextiles was characterized for two types of geotextiles (nee- diepunched and the rmosea led) and for two different initial saturation degrees for the needlepunched geotextile. The main results showed that when placed wet the needlepunched geotextile had no influence. When placed dry, it homogenized the flow in its surroundings and thus allowed better contact between heavy metals and the reactive soil, resulting in an increase of their retention. The thermosealed geotextile, placed dry, homogenized the flow and increased retention over a larger area, resulting in optimal global retention. In conclusion, geotextiles could be used in infiltration basins, provided that their effect on both flow and heavy metal retention is optimized by appropriate design-choice of geotextiles-and appropriate monitoring-control of hydric conditions. [ABSTRACT FROM AUTHOR]

An understanding of preferential flow in the vadose zone is crucial for the prediction of the fate of pollutants. Infiltration basins, developed to mitigate the adverse effects of impervious surfaces in urban areas, are established above strongly heterogeneous and highly permeable deposits and thus are prone to preferential flow and enhanced pollutant transport. This study numerically investigates the establishment of preferential flow in an infiltration basin in the Lyon suburbs (France) established over a highly heterogeneous glaciofluvial deposit covering much of the Lyon region. An investigation of the soil transect (13.5 m long and 2.5 m deep) provided full characterization of lithology and hydraulic properties of present lithofacies. Numerical modeling with the HYDRUS-2D model of water flow in the transect was used to identify the effects of individual lithofacies that constitute the deposit. Multiple scenarios that considered different levels of heterogeneity were evaluated. Preferential flow was studied for several values of infiltration rates applied after a long dry period. The numerical study shows that the high contrast in hydraulic properties of different lithofacies triggers the establishment of preferential flow (capillary barriers and funneled flow). Preferential flow develops mainly for low water fluxes imposed at the surface. The role of individual lithofacies in triggering preferential flow depends on their shapes (layering versus inclusions) and their sizes. While lenses and inclusions produce preferential flow pathways, the presence of the surface layer has no effect on the development of preferential flow and it only affects the effective hydraulic conductivity of the heterogeneous transect.

Reports on the impact of the interaction of contaminants on the management of contamination. Modification of the transport of heavy metals in soil; Performance of experiments on the elution of tracers and heavy metals; Comparison of water flow and metal transport.

Describes the implementation of a monitoring system to measure impact of stormwater runoff infiltration. Ecological processes; Groundwater ecosystems; Infiltration; Metrology; Soil monitoring; Stormwater.