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Abstract: In this paper the design and simulation of two renewable-based standalone energy systems for application in two different locations are carried out. More specifically, the systems examined are a standalone PV system and a standalone hybrid PV–Wind system. The locations considered are those of Nicosia, Cyprus and Nice, France. These two locations have similar Mediterranean climates with different wind potential and slightly different solar irradiation levels which lead to interesting conclusions concerning the application of such systems. Since both systems are standalone, the energy produced is stored in a battery bank. The software used for the modeling and simulation processes is TRNSYS. The results of this paper define the optimal type and size of the renewable-based system to be applied in each of the locations examined at the minimum system cost. Additionally, a comparison of the two systems for both locations in terms of technical and economic aspects is presented where it is concluded that the type of the system to be used in each case is directly depended on the climatic characteristics of the specific location. More specifically, for Nicosia the solely PV system provides a better option than the PV–Wind hybrid system while in Nice the opposite is the case. [Copyright &y& Elsevier]

Summary: This paper presents a detailed analysis of the September 8–9, 2002 flash flood event in the Gard region (southern France) using two distributed hydrological models: CVN built within the LIQUID® hydrological platform and MARINE. The models differ in terms of spatial discretization, infiltration and water redistribution representation, and river flow transfer. MARINE can also account for subsurface lateral flow. Both models are set up using the same available information, namely a DEM and a pedology map. They are forced with high resolution radar rainfall data over a set of 18 sub-catchments ranging from 2.5 to 99km2 and are run without calibration. To begin with, models simulations are assessed against post field estimates of the time of peak and the maximum peak discharge showing a fair agreement for both models. The results are then discussed in terms of flow dynamics, runoff coefficients and soil saturation dynamics. The contribution of the subsurface lateral flow is also quantified using the MARINE model. This analysis highlights that rainfall remains the first controlling factor of flash flood dynamics. High rainfall peak intensities are very influential of the maximum peak discharge for both models, but especially for the CVN model which has a simplified overland flow transfer. The river bed roughness also influences the peak intensity and time. Soil spatial representation is shown to have a significant role on runoff coefficients and on the spatial variability of saturation dynamics. Simulated soil saturation is found to be strongly related with soil depth and initial storage deficit maps, due to a full saturation of most of the area at the end of the event. When activated, the signature of subsurface lateral flow is also visible in the spatial patterns of soil saturation with higher values concentrating along the river network. However, the data currently available do not allow the assessment of both patterns. The paper concludes with a set of recommendations for enhancing field observations in order to progress in process understanding and gather a larger set of data to improve the realism of distributed models. [Copyright &y& Elsevier]

Abstract: Ventilation is a crucial element while managing fire events in tunnels. This paper deals with ventilation strategies to be applied in case of fire in a long tunnel. The Frejus road tunnel has been considered as an application. This is a single tube road tunnel with semi-transversal ventilation. Ordinary and emergency ventilations are operated by using dedicated supply and extraction ducts. The optimal configuration of the ventilation system depends not only on the fire size and its location, but also on the pressure at the portals (which is an important factor in the case of a long tunnel), the traffic, etc. In this paper, some particular scenarios are analyzed. These scenarios correspond to particular fire locations, fire sizes, pressure and temperature at the portals, and traffic. Fuzzy-logic approach is applied in order to generalize the results obtained in these scenarios, so that any event can be managed. Some transient simulations are performed in order to test the control strategy. The values of input parameters selected for the test cases are not coincident with those selected to build the control strategy. Transient simulations allows one to check not only the extension of the tunnel portion occupied by smoke, but also the time required to confine the smoke front. [Copyright &y& Elsevier]

In France like in many other countries, the soil is monitored at the locations of a regular, square grid thus forming a systematic sample (SY). This sampling design leads to good spatial coverage, enhancing the precision of design-based estimates of spatial means and totals. Design-based estimation of the mean or total from SY samples is straightforward. However, an unbiased estimator of the sampling variance of the estimated mean or total does not exist. This paper compares five variance approximations, being the simple random (SI), stratified simple random (STSI), Geary's spatial autocorrelation C index (Geary), Moran's I index (Moran), and the model-based (MB) approximation in a simulation study and a real-world case study. In a simulation study the model distribution of the conditional bias (conditioned on a simulated reality) of the variance approximations is estimated for various variograms and two sample sizes. In the case study the data of the first campaign of the French Soil Monitoring Network are used to estimate the spatial means of six soil variables (C, Tl, Cd, Ni, K, Mn) for aggregated soil map units of France, and to approximate their sampling variances. The bias in the approximated variances is explored with MODIS-NDVI data. With variograms with no or a small relative nugget variance approximation STSI and MB are the best choices. In situations with large relative nugget STSI is to be preferred over MB as MB then may somewhat underestimate the variance. Moran and SI should be avoided as approximation methods, as they seriously underestimate (Moran) and overestimate (SI) the variance in many cases. The approximated standard error of total soil organic carbon stock in France as obtained with MB was 0.0335 Pg, which was small compared to the estimated stock of 3.580 Pg. [ABSTRACT FROM AUTHOR]

Abstract: Most worldwide fish stocks are overexploited, and so exploited beyond the Maximum Sustainable Yield (MSY) and the Maximum Economic Yield (MEY). Not exploiting fisheries resources at MSY or MEY leads to the loss of production and rents from the fisheries. A large part of the EU fisheries are managed based on single species stock assessments; however, in reality, most species are caught together with other species and by different fleets. In multi-species and multi-fleet fisheries, single species assessments, and consequently MSY and MEY reference points, are often not valid, and so the catch recommendations. In this paper it is investigated the MSY and MEY estimation in multi-species and multi-fleet fisheries in comparison to single species assessments. Analyses are applied to the Bay of Biscay demersal fishery using the IAM bio-economic model. The impact of exploiting at MSY and MEY on the optimal effort allocation between fleets with different exploitation patterns and economic structures is analyzed. When accounting for the multi-species nature of the fishery, MSY landings are 0.4% to 2.7% lower than the single species simulations estimates. When accounting for the multi-fleet nature of the fishery, MSY landings are 27.2% to 30.2% higher than the single-fleet estimates. When considering the multi-fleet characteristics, MEY landings are 6.6% higher and profits are 66.5% higher than in the single-fleet simulation. Optimal effort at MEY is lower than at MSY, but when accounting for multi-fleet the optimal effort decreases for some fleets while increases for gillnetters. The results also provide an estimation of the profits at MEY (or costs of not being at MEY). Profits can be then up to 10.7 times larger than the current profits (256 million Euros compared to the current 24 million Euros). [Copyright &y& Elsevier]

Abstract: This paper addresses the relationship between anthropogenic forest habitat fragmentation and the form of urban patterns. Using a two-step methodology we first generate 40 theoretical residential development scenarios following a repeatable procedure; the simulated urban forms are either moderately compact or fractal. Then, we compare the scenarios according to the functional connectivity of the remaining forest habitat using a graph-based approach. The methodology is applied to the urban region of Besançon (France), where forest surfaces are considered as a generic habitat for several animal species. Results obtained show that fractal scenarios of residential development are almost equivalent to moderately compact scenarios regarding the connectivity of forest habitat when the residential development is weak. In the case of a more intense residential development, fractal scenarios are superior to nonfractal scenarios when low dispersal distances of animals are concerned. [Copyright &y& Elsevier]

Abstract: The paper seeks to quantify the effect of urban politics on the microclimate of the city of Nantes (France), in particular those initiated by the sanitarians in the mid-19th century to find a remedy for the insalubrity that had been developing with urban densification since the late 17th century. Intensive historical research was first carried out in order to define and date the major transformations undergone by the city, its structure (densification, then widening of the streets, filling of water courses), the lifestyle habits (heating) or the building practices (appearance of stone and paving, higher buildings, insulation). This led to the definition of 5 characteristic states of the city, in 1680, 1756, 1835, 1880 and 1945. A numerical modelling approach is then used to simulate the urban microclimate of Nantes for these 5 states. The historical information (plans, illustrations) is incorporated into a Geographic Information System in order to determine the general characteristics of the city at the different dates. These are then used to initialize the TEB model which simulates urban energy behaviour and microclimate. While air temperature increases regularly and evaporation decreases (as expected) with greater amount of mineral surfaces, the evolution of humidity is more surprising. Air humidity first increases until the 1850s due to narrower streets. Then it decreases further with the sanitarian transformations which allow the streets to become ventilated and dry. This study gives a good indication of how town-planning actions can, in the long term, influence the urban climate. [Copyright &y& Elsevier]

Summary: This paper presents the application of the Analytic Element Method (AEM) and particle swarm optimization (PSO) based simulation–optimization model for the solution of groundwater management problems. The AEM-PSO model developed was applied to the Dore river basin, France to solve two groundwater hydraulic management problems: (1) maximum pumping from an aquifer, (2) minimum cost to develop the new pumping well system. Discharge as well as location of the pumping wells were taken as the decision variables. The influence of the piping length was examined in the total development cost for new wells. The optimal number of wells was also calculated by applying the model to different sets of wells. The constraints of the problem were identified with the help of water authority, stakeholders and officials. The AEM flow model was developed to facilitate the management model in particular, as in each iteration optimization model calls a simulation model to calculate the values of groundwater heads. The AEM-PSO model was found to be efficient in identifying the optimal location and discharge of the pumping wells. The penalty function approach was found to be valuable in PSO and also acceptable for groundwater hydraulic management problems. [Copyright &y& Elsevier]

Abstract: Tritium (3H or T) is one of the major radionuclides released by nuclear power plants (NPP) into rivers. However, tritiated water (HTO) flux from water to air is seldom considered when assessing health effects of such releases. The aim of this paper is to present the result of a research program, called LORA, conducted on the Loire River (France). To improve our understanding of HTO flux from surface water to air, three field campaigns were organised during the NPP’s radioactive releases to measure simultaneously the activity concentrations in air on the riverbank, using an innovative system, and in river water. The measurements showed that during radioactive releases, water vapour was enriched in 3H. These results were used to calibrate exchange velocities. The average of these estimated exchange velocities was more than one order of magnitude higher than those calculated in the literature from indoor experiments. The variability of these values was also larger, showing that outdoor studies cover a wide range of conditions influencing HTO flux. No correlation was observed between exchanges velocities and meteorological conditions. However, there was a significant difference between day and night with a higher value observed during the day. Two approaches used to calculate HTO evaporation from water (i.e. the approach based on water evaporation and the approach considering that HTO follows its own concentration gradient) were included in a hydrodynamic model, which was used to evaluate HTO air activity along the Loire River. In conclusion, only the approach considering that HTO follows its own gradient led to a good agreement between measurements and predictions. A one-year simulation was done to estimate the contribution of this process to the dose. Its contribution can be considered as negligible in this case compared to the other pathways such as ingestion of water or foodstuffs. [Copyright &y& Elsevier]

Summary: In the general context of field experiment design, this paper presents a modeling study that quantifies the respective impact of rainfall estimation and soil variability on the simulated discharge for an extreme event in southern France. The CVN distributed hydrological model, built within the LIQUID® modeling platform is used. The method is illustrated for two medium sized catchments, Saumane (99km2) and Uzès (88km2) using raingauges and two radar estimates. The soil properties are extracted from an existing soil database provided for the whole region. The model parameter specification uses available observation and a priori hydrological knowledge. No parameter adjustment is performed. For model evaluation on the regional scale, simulated maximum peak discharges are compared with post-flood estimations for 32 catchments. The area of these catchments ranges from 2.5 to 99km2 and model results are satisfactory. Then, the study focuses on the Saumane and Uzès catchments. A sensitivity analysis highlights the role of the Manning roughness coefficient on the simulated hydrographs dynamics. The impact of the bottom boundary condition of the infiltration and water redistribution module is also shown for the gauged Saumane catchment. Then the impact of rainfall input and soil spatial variability is presented. The results show that (i) the use of radar data is necessary to properly simulate the flood dynamics; (ii) although radar volume-scanning strategy has been shown to give more accurate results on a pixel/gauge comparison of the rainfall estimations, it is not necessarily the case when catchment averaged amounts are considered, especially for catchments in mountainous areas; (iii) the impact of the variability in soil properties on the simulated discharges is of the same order of magnitude as the impact of differences in rainfall estimation; (iv) the flood dynamics presents two phases: the first one, mainly controlled by the soil properties and the second one, since the soils are saturated, controlled by the rainfall variability. Therefore, uncertainties on both observations need to be mitigated in order to improve flash-flood understanding. [Copyright &y& Elsevier]

Abstract: A model for the spatial variation of aerosol concentrations and deposition along the coastal zone is of great interest for studies on air and water quality. In coastal areas, sea-spray aerosols generated at the sea surface by the interaction between wind and waves add to a continental contribution emitted from natural and/or anthropogenic sources. To include coastal effects in the model for the prediction of aerosol concentrations, Piazzola et al. (2003) developed the coastal Mediterranean aerosol model. The present paper deals with an extension of the Mediterranean coastal aerosol to a regional scale applied to the prediction of the sea surface flux deposition. This was achieved by the development of an automatic coupling process between the aerosol model and a regional meso-scale meteorological model which allows accounting for the details of the orography of the coast. The results show a non-homogeneous spatial coverage of aerosol concentrations over the northwestern Mediterranean. The simulations were then validated using aerosol size distributions recorded on board the ship “Atalante” for two kinds of meteorological conditions. Error calculations show a good performance of the coupling process since it predicts the aerosol concentration to within a maximum factor of 3 for particle radii between 0.1 to 10µm. This process was then used to provide the spatial distribution of the particle deposition fluxes over the study area. [Copyright &y& Elsevier]

Abstract: This paper presents a dynamic model of the helium flow in the cryogenic distribution line (QRL) used in the Large Hadron Collider (LHC) at CERN. The study is focused on the return pumping line, which transports gaseous helium at low pressure and temperature over . Our aim is to propose a new real-time model of the QRL while taking into account the non-homogeneous transport phenomena. The flow model is based on 1D Euler equations and considers convection heat transfers, hydrostatic pressure and friction pressure drops. These equations are discretized using a finite difference method based on an upwind scheme. A specific model for the interconnection cells is also proposed. The corresponding simulation results are compared with experimental measurements of a heat wave along the line that results from a quench of a superconducting magnet. Different hypotheses are presented and the influence of specific parameters is discussed. [Copyright &y& Elsevier]

Abstract: This paper presents a process and control simulator for industrial helium cryogenic plants controlled by Programmable Logic Controllers (PLC). This simulator can be used for different purposes such as operator training, test of the PLC programs or the optimization of the plant. The different component models used in the simulator are detailed and explained. Various large scale cryogenic plants used for the particle accelerator LHC (Large Hadron Collider) at CERN have been modeled and simulated. The good agreement between the simulation results and the dynamic behavior of real plants is demonstrated with experimental results. Various discussions complete the presentation. [Copyright &y& Elsevier]

Abstract: We present a new method for modeling the hadronic recoil in events produced at hadron colliders. The recoil is chosen from a library of recoils in data events and overlaid on a simulated event. Implementation of this method requires that the data recoil library describe the properties of the measured recoil as a function of the true, rather than the measured, transverse momentum of the boson. We address this issue using a multidimensional Bayesian unfolding technique. We estimate the statistical and systematic uncertainties from this method for the W boson mass and width measurements assuming of data from the Fermilab Tevatron. The uncertainties are found to be small and comparable to those of a more traditional parameterized recoil model. For the high precision measurements that will be possible with data from Run II of the Fermilab Tevatron and from the CERN LHC, the method presented in this paper may be advantageous, since it does not require an understanding of the measured recoil from first principles. [Copyright &y& Elsevier]

Abstract: The paper evaluates atmospheric reanalysis as possible forcing of model simulations of the ocean circulation inter-annual variability in the Gulf of Lions in the Western Mediterranean Sea between 1990 and 2000. The sensitivity of the coastal atmospheric patterns to the model resolution is investigated using the REMO regional climate model (18km, 1h), and the recent global atmospheric reanalysis ERA40 (125km, 6h). At scales from a few years to a few days, both atmospheric data sets exhibit a very similar weather, and agreement between REMO and ERA40 is especially good on the seasonal cycle and at the daily variability scale. At smaller scales, REMO reproduces more realistic spatio-temporal patterns in the ocean forcing: specific wind systems, particular atmospheric behaviour on the shelf, diurnal cycle, sea-breeze. Ocean twin experiments (1990–1993) clearly underline REMO skills to drive dominant oceanic processes in this microtidal area. Finer wind patterns induce a more realistic circulation and hydrology of the shelf water: unique shelf circulation, upwelling, temperature and salinity exchanges at the shelf break. The hourly sampling of REMO introduces a diurnal forcing which enhances the behaviour of the ocean mixed layer. In addition, the more numerous wind extremes modify the exchanges at the shelf break: favouring the export of dense shelf water, enhancing the mesoscale variability and the interactions of the along slope current with the bathymetry. [Copyright &y& Elsevier]

Abstract: CO2 injection into a depleted hydrocarbon field or aquifer may give rise to a variety of coupled physical and chemical processes. During CO2 injection, the increase in pore pressure can induce reservoir expansion. As a result the in situ stress field may change in and around the reservoir. The geomechanical behaviour induced by oil production followed by CO2 injections into an oil field reservoir in the Paris Basin has been numerically modelled. This paper deals with an evaluation of the induced deformations and in situ stress changes, and their potential effects on faults, using a 3D geomechanical model. The geomechanical analysis of the reservoir–caprock system was carried out as a feasibility study using pressure information in a “one way” coupling, where pressures issued from reservoir simulations were integrated as input for a geomechanical model. The results show that under specific assumptions the mechanical effects of CO2 injection do not affect the mechanical stability of the reservoir–caprock system. The ground vertical movement at the surface ranges from −2mm during oil production to +2.5mm during CO2 injection. Furthermore, the changes in in situ stresses predicted under specific assumptions by geomechanical modelling are not significant enough to jeopardize the mechanical stability of the reservoir and caprock. The stress changes issued from the 3D geomechanical modelling are also combined with a Mohr–Coulomb analysis to determine the fault slip tendency. By integrating the stress changes issued from the geomechanical modelling into the fault stability analysis, the critical pore pressure for fault reactivation is higher than calculated for the fault stability analysis considering constant horizontal stresses. [Copyright &y& Elsevier]

In this paper, we report an application of neural networks to simulate daily nitrate-nitrogen and suspended sediment fluxes from a small 7.1km2 agricultural catchment (Melarchez), 70km east of Paris, France. Nitrate-nitrogen and sediment losses are only a few possible consequences of soil erosion and biochemical applications associated to human activities such as intensive agriculture. Stacked multilayer perceptrons models (MLPs) like the ones explored here are based on commonly available inputs and yet are reasonably accurate considering their simplicity and ease of implementation. Note that the simulation does not resort on water quality flux observations at previous time steps as model inputs, which would be appropriate, for example, to predict the water chemistry of a drinking water plant a few time steps ahead. The water quality fluxes are strictly mapped to historical mean flux values and to hydro-climatic variables such as stream flow, rainfall, and soil moisture index (12 model input candidates in total), allowing its usage even when no flux observations are available. Self-organizing feature maps based on the network structure established by Kohonen were employed first to produce the training and the testing data sets, with the intent to produce statistically close subsets so that any difference in model performance between validation and testing has to be associated to the model and not to the data subsets. The stacked MLPs reached different levels of performance simulating the nitrate-nitrogen flux and the suspended sediment flux. In the first instance, 2-input stacked MLP nitrate-nitrogen simulations, based on the same-day stream flow and on the 80-cm soil moisture index, have a performance of almost 90% according to the efficiency index. On the other hand, the performance of 3-input stacked MLPs (same-day stream flow, same-day historical flux, and same-day stream flow increment) reached a little more than 75% according to the same criterion. The results presented here are deemed already promising enough, and should encourage water resources managers to implement simple models whenever appropriate. [Copyright &y& Elsevier]

Abstract: Morphodynamic modeling systems are being subjected to a growing development over the last decade and increasingly appear as valuable tools for understanding and predicting coastal dynamics and morphological changes. The recent improvements of a 2DH unstructured grid morphodynamic modeling system are presented in this paper and include the implementation of an adaptive morphodynamic time step, the integration and full coupling of a wave model and the forcing by large scale wave and tide models. This modeling system was first applied to a dissipative wave-dominated beach located on the French coast, where the availability of field data allowed for a fine calibration and validation of wave-induced flows and longshore transport, and an assessment of the various sediment transport formulae. The modeling system was then applied to a very dynamic Portuguese tidal inlet where numerical tests show the computational efficiency of using an adaptive time step. Morphodynamic simulations of this inlet with real wave and tidal forcings resulted in realistic morphological predictions. The two applications show that the improved modeling system is able to predict hydrodynamics, transport and morphological evolutions in complex coastal environments. [Copyright &y& Elsevier]

Abstract: The paper presents time-domain simulation for power electronic device equivalent impedance computation at ripple control signal frequency. The ripple control used by the grid is a low frequency voltage signal superimposed at MV substation. In France, the frequency used by grid ripple control systems is 175Hz. It is well known that some customer loads can disturb ripple control signal transmission such as capacitor bank, distributed generator, etc. These equipments can influence or disturb ripple control signal by two main ways: presence of a small impedance or an important interharmonic current injection at ripple control frequency. In transient state, even a symmetrical static converter can produce interharmonic currents. In site studies, some customer power electronic device (variable speed drive for example) is often modeled by an infinite impedance at ripple control frequency. However, site measurements and simulations show that this simplification can cause in some case important error in ripple control signal level assessment. The main purpose of this study is to define ripple control frequency equivalent impedances of typical converters used in industry. The study shows that a voltage source converter (rectifier with dc capacitor structure) gives a relative small impedance at ripple control frequency. It is recommended to integrate this impedance in performing ripple control signal propagation study by means of frequency-domain software. [Copyright &y& Elsevier]

Abstract: The paper presents a simplified model called PESTDRAIN. It simulates pesticide transport in a subsurface tile-drained field. It computes surface runoff and tile-drainage flow rates, along with the associated pesticide concentrations, with a variable event-driven time step. PESTDRAIN consists of three coupled modules: SIDRA, SIRUP and SILASOL. SIDRA and SIRUP are the water flow simulation modules in the saturated and unsaturated zones, respectively. SIDRA follows a simplified physically based approach while SIRUP follows a conceptual capacitive approach. SILASOL is the solute transport module for both the saturated and unsaturated zones and is based on transfer functions. It includes simple representations of adsorption and degradation of pesticides. PESTDRAIN was tested on field data sets collected for three drainage seasons at the La Jaillière experimental site in north-western France, for the wheat herbicides isoproturon (IPU) and diflufenican (DFF). After model calibration, relative errors for drainage and surface runoff flows over the season were 14% and 4%, respectively, and the Nash–Sutcliffe efficiency coefficient () value for drainage discharge was 0.58. A fair reproduction of a high temporal resolution IPU concentration data set in drainage discharge was also obtained (). For the validation data sets, PESTDRAIN was able to simulate accurately drainage discharge with Nash–Sutcliffe efficiency coefficients of 0.57 and 0.69. The global was 0.44 for all flow-weighted average weekly concentrations in drainage. Relative errors for the pesticide losses were 2.5% and 35% (IPU), and 60% (DFF). For surface runoff the results were not as accurate, but they remained correct in terms of time location and order of magnitude. Although further validation is necessary with more field data, PESTDRAIN appears as a promising tool for agricultural water management. [Copyright &y& Elsevier]

Abstract: This paper describes a tool called ‘Numerical Platon’ developed by the French Atomic Energy Commission (CEA). It provides a freely available (GNU LGPL license) interface for coupling scientific computing applications to various freeware linear solver libraries (essentially PETSc, SuperLU and HyPre), together with some proprietary CEA solvers, for high-performance computers that may be used in industrial software written in various programming languages. This tool was developed as part of considerable efforts by the CEA Nuclear Energy Division in the past years to promote massively parallel software and on-shelf parallel tools to help develop new generation simulation codes. After the presentation of the package architecture and the available algorithms, we show examples of how Numerical Platon is used in sequential and parallel CEA codes. Comparing with in-house solvers, the gain in terms of increases in computation capacities or in terms of parallel performances is notable, without considerable extra development cost. [Copyright &y& Elsevier]

Summary: The main objective of this paper is to evaluate a threshold-based flash flood warning method, by considering a wide range of climatic and physiographic conditions, and by focusing on ungauged basins. The method is derived from the flash flood guidance (FFG, hereafter) approach. The FFG is the depth of rain of a given duration, taken as uniform in space and time on a certain basin, necessary to cause minor flooding at the outlet of the considered basin. This rainfall depth, which is computed based on a hydrological model, is compared to either real-time-observed or forecasted rainfall of the same duration and on the same basin. If the nowcasted or forecasted rainfall depth is greater than the FFG, then flooding in the basin is considered likely. The study provides an assessment of this technique based on operational quality data from 11 mountainous basins (six nested included in five larger parent basins) located in north-eastern Italy and central France. The model used in this study is a semi-distributed conceptual rainfall–runoff model, following the structure of the PDM (probability distributed moisture) model. Two general questions are addressed: (1) How does the efficiency of the method evolve when the simulation parameters can not be calibrated but must be transposed from parent gauged basins to ungauged basins? (2) How sensitive are the results to the method used to estimate the initial soil moisture status? System performances are evaluated by means of categorical statistics, such as the critical success index (CSI). Results show that overall CSI is equal to 0.43 for the parent basins, where the hydrological model has been calibrated. CSI reduces to 0.28 for the interior basins, when model parameters are transposed from parent basins, and to 0.21, when both model parameters and soil moisture status is transposed from parent basins. Performance differences between FFG and use of time-constant soil moisture status are very high for the parent basins and decrease with decreasing the system accuracy. The percent difference amounts to 53% for the parent basins, to 25% for interior basins with parameter transposition, and to 19% for interior basins with parameter and soil moisture status transposition. These results improve our understanding of the applicability and reliability of this method at various scales and under various scenarios of data availability. [Copyright &y& Elsevier]

Abstract: Large stone course structures such as Roman amphitheatres or aqueducts can be modelled as collections of rigid or deformable discrete elements. The “Non-Smooth Contact Dynamics” (NSCD) computational method, on which the LMGC90®code used in this paper is based, is well suited to the dynamic simulation of the behaviour of such large collections of bodies with complex three-dimensional geometries. The obtained results for the simulation of the dynamic excitation for two examples of real antique structures, “Nîmes arena” and “Arles aqueduct” in France, are presented. The mechanical behaviour of the numerical models is then examined and, where possible, compared to the present state of the two-millennia-old structures. [Copyright &y& Elsevier]

Periphytic biomass has an important influence on the water quality of many shallow streams. The purpose of this paper is to synthesize the knowledge obtained on periphyton during the PIREN Seine research program. Periphyton was sampled using chl a measurements by acetone extraction and oxygen measurements with microelectrodes. The experiments reveal the presence of an important fixed biomass ranging between 123 and 850 mgchl a m−2 and the mean gross production (photosynthesis) is shown to range between 180 and 315 mgC m−2 h−1. An independent approach was performed using the ProSe model, which simulates transport and biogeochemical processes in 22 km of the Grand Morin stream. A strong agreement between in situ measurements and the model results was obtained. The gross production obtained using ProSe is 220 mgC m−2 h−1 for the periphyton, which matches the experimental data. Although the net photosynthetic activity of the phytoplankton (0. 84 gC gC−1 d−1) is higher than the periphytic one (0. 33 gC gC−1 d −1), the absolute periphytic activity is greater since the mean biomass (3. 4 gC m− 2) is 10 times higher than the phytoplanktonic one (0. 3 gC m−2), due to the short residence time of the water body (1. 5d). [Copyright &y& Elsevier]

Abstract: The ATLAS detector is a general purpose experiment designed to fully exploit the discovery potential of the Large Hadron Collider (LHC) at a nominal luminosity of 1034 cm−2 s−1. It is expected that after several years of successful data-taking, the LHC physics program will be extended by increasing the peak luminosity by one order of magnitude. For ATLAS, an upgrade scenario will imply the complete replacement of the Inner Detector (ID), since the current tracker will not provide the required performance due to cumulated radiation damage and a dramatic increase in the detector occupancy. In this paper, a proposal of a double-sided silicon micro-strip module for the short-strip region of the future ATLAS ID is presented. The expected thermal performance based upon detailed FEA simulations is discussed. First electrical results from a prototype version of the next generation readout front-end chips are also shown. [Copyright &y& Elsevier]