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Evaluating the Spatial Uncertainty of Future Land Abandonment in a Mountain Valley(Vicdessos, Pyrenees-France): Insights from Model Parameterization and Experiments

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Journal of Mountain Science 2015年第5期12卷 1095-1112页

作者： Thomas Houet Laure Vacquié David Sheeren GEOde UMR 5602 CNRS –UT2J Université Toulouse Jean Jaurès Maison de la recherche 5 allées Antonio Machado31058 Toulouse Cedex Dynafor UMR 1201 INRA/INPT-ENSAT Ecole Nationale Supérieure Agronomique de Toulouse Avenue del’Agrobiopole B.P. 32607 - Auzeville-Tolosane 31326 - Castanet-Tolosan Cédex

European mountains are particularly sensitive to climatic disruptions and land use *** latter leads to high rates of natural reforestation over the last 50 years. Faced with the challenge of predicting possible impacts on ecosystem services,LUCC models offer new opportunities for land managers to adapt or mitigate their *** the spatial uncertainty of future LUCC is crucial for the definition of sustainable land use strategies. However, the sources of uncertainty may differ, including the input parameters, the model itself, and the wide range of possible futures. The aim of this paper is to propose a method to assess the probability of occurrence of future LUCC that combines the inherent uncertainty of model parameterization and the ensemble uncertainty of the future based scenarios. For this purpose, we used the Land Change Modeler tool to simulate future LUCC on a study site located in the Pyrenees Mountains(France) and two scenarios illustrating two land use strategies. The model was parameterized with the same driving factors used for its calibration. The definition of ‘static vs. dynamic' and ‘quantitative ***(discretized)' driving factors, and their combination resulted in four parameterizations. The combination of model outcomes produced maps of the spatial uncertainty of future LUCC. This work involves adapting the definition of spatial uncertainty in the literature to future-based LUCC studies. It goes beyond the uncertainty of simulation models by integrating the uncertainty of the future to provide maps to help decision makers and land managers.

关键词： Land use Land cover Scenario Model Mountainous reforestation Land abandonment Landmanagement

Sedimentary dynamics and ecological state of Nakta tidal flat (littoral), South of Sfax, Gulf of Gabès,Tunisia

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Chinese Journal Of Geochemistry 2007年第3期26卷 244-251页

作者： Gargouri-Ben Ayed Z. Souissi R. Soussi M. Abdeljaouad S. Zouari K. Laboratoire de radio-analyses et environnement Ecole Nationale d'Ingénieurs de Sfax BP W 3038 Sfax Tunisie université Tunis El Manar Faculté des Sciences de Tunis Département de géologie 2092 Tunis Tunisie

The tidal flat of Nakta is located in the northern part of the gulf of Gabes and in the southern coast of Sfax. It corresponds to a flat reef protected from less topography, with a slope ranging between 2° and 4°, which borders the Gargour Wadi. The study sector is renowned to have moderate hydrodynamics which lasts almost for two millenary (14C isotopic dating). The sedimentological study of the Nakta tidal flat revealed different facies: fine-grained sand in the intertidal zone and carbonated muddy sand in the infratidal zone. Equilibrium state of the Nakta ecosystem depends entirely on tide currents, which mainly inhibit drift currents. The Nakta tidal flat is characterized by a variety of faunal species (Cerastoderma glaucum, Arca noe, Cardita antiquatus, Chlamys varied, Ruditapes deccussatus, Tapes rhomboids, Pinctada radiate, etc.) and floristic diversities (Halocnemum strobilacum, Halimione portulacoides, Enteromorpha linza, Ulva rigida, Cymodocea nodosa, Posidonia oceanica). The species are abundant in the infratidal zone, while in its intertidal zone, faunal species remain little diversified and are dominated by limivorous diggering. The paleogeographic study of the Nakta tidal flat showed the alternation of regression and transgression periods.

关键词：沿海地区沉积物矿物学放射测年学重金属

An evolutionary computational framework for capacity-safety trade-off in an air transportation network

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Chinese Journal of Aeronautics 2019年第4期32卷 999-1010页

作者： Md.Murad HOSSAIN Sameer ALAM Daniel deLAHAYE School of Engineering and Information Technology University of New South Wales School of Mechanical and Aerospace Engineering Nanyang Technological University MAIAA Laboratory Ecole Nationale de l'Aviation Civile

Airspace safety and airport capacity are two key challenges to sustain the growth in Air Transportation. In this paper, we model the Air Transportation Network as two sub-networks of airspace and airports, such that the safety and capacity of the overall Air Transportation network emerge from the interaction between the two. We propose a safety-capacity trade-off approach,using a computational framework, where the two networks can inter-act and the trade-off between capacity and safety in an Air Transport Network can be established. The framework comprise of an evolutionary computation based air traffic scenario generation using a flow capacity estimation module(for capacity), Collision risk estimation module(for safety) and an air traffic simulation module(for evaluation). The proposed methodology to evolve air traffic scenarios such that it minimizes collision risk for given capacity estimation was tested on two different air transport network topologies(random and small-world) with the same number of airports. Experimental results indicate that though airspace collision risk increases almost linearly with the increasing flow(flow intensity) in the corresponding airport network, the critical flow depend on the underlying network configuration. It was also found that, in general, the capacity upper bound depends not only on the connectivity among airports and their individual performances but also the configuration of waypoints and mid-air interactions among conflicts. Results also show that airport network can accommodate more traffic in terms of capacity but the corresponding airspace network cannot accommodate the resulting traffic flow due to the bounds on collision risk.

关键词： Airport network Airspace capacity Airspace safety Collision risk Flow intensity

A low power consumption control scheme:application to a piezostack-based active mount

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Frontiers of Mechanical Engineering 2013年第4期8卷 383-389页

作者： T.LOUKIL O.BAREILLE M.N.ICHCHOU M.HADDAR LTDS Ecolc Centrale de Lyon36 Avenue Guy de Collongue U2MP Ecole Nationale d'lngenieurs de Sfax

Piezostack-based active mounts have shown great efficiency for vibration control in a wide frequency *** this paper,we investigate the performances of the global semi-active control strategy presented by Ichchou et al.[1]for a control system consisting of an active mount and a supported *** control strategy allows extracting vibrations energy of the supported mass,storing it in accumulators to be reused for powering in part the actuators(two piezostacks).Consequently,energy needs are reduced versus good control performances comparable to those of the active control based on the negative velocity *** performances of the controller are evaluated in both frequency(transmitted force)and time(acceleration)domains which show that vibrations of the supported mass due to base excitations are efficiently attenuated with the proposed *** energetic analysis confirms the reduced energy requirement compared to the active scheme.

关键词： hybrid mount energy control piezoelectric harvesting

Ultrasound-assistant preparation of Cu-SAPO-34 nanocatalyst for selective catalytic reduction of NO by NH_3

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Journal of Environmental Sciences 2015年第9期27卷 135-143页

作者： Parvaneh Nakhostin Panahi Ali Niaei Darush Salari Seyed Mahdi Mousavi Gérard delahay department of Chemistry Faculty of Science University of Zanjan department of Chemical Engineering & Petroleum University of Tabriz department of Applied Chemistry Faculty of Chemistry University of Tabriz Faculty of Chemistry University of Kashan Institut Charles Gerhardt UMR 5253 CNRS/UM2/ENSCM/UM1 Equipe"Matériaux Avancés pour la Catalyse et la Santé"Ecole Nationale Supérieure de Chimie de Montpellier 8 rue de l'Ecole Normale34296 Montpellier cedex France

The influence of the various preparation methods of Cu-SAPO-34 nanocatalysts on the selective catalytic reduction of NO with NH3 under excess oxygen was studied. Cu-SAPO-34 nanocatalysts were prepared by using four techniques： conventional impregnation（IM）,ultrasound-enhanced impregnation（UIM）, conventional deposition precipitation（DP） using Na OH and homogeneous deposition precipitation（HDP） using urea. These catalysts were characterized in detail by various techniques such as N2-sorption, XRD, TEM, H2-TPR,NH3-TPD and XPS to understand the catalyst structure, the nature and the dispersed state of the copper species, and the acid sites for NH3 adsorption. All of the nanocatalysts showed high activities for NO removal. However, the activities were different and followed the sequence of Cu-SAPO-34（UIM）〉 Cu-SAPO-34（HDP）〉 Cu-SAPO-34（IM）〉 Cu-SAPO-34（DP）.Based on the obtained results, it was concluded that the NO conversion on Cu-SAPO-34 nanocatalysts was mainly related to the high reducibility of the isolated Cu^2＋ions and Cu O species, the number of the acid sites and the dispersion of Cu O species on SAPO-34.

关键词： NO NH3-SCR Cu-SAPO-34 Ultrasonic impregnation

Water Production by Condensation of Wet Air

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Modern Mechanical Engineering 2020年第2期10卷 17-24页

作者： Louis Okotaka Ebale Guy Dieudonne Moukandi N’kaya Wilfrid Kombo Feldha Kibongani Laboratoire de Mécanique Energétique et Ingénierie Ecole Nationale Supérieure Polytechnique Université Marien Ngouabi Brazzaville Congo

It is now assumed that climate warming is effective and noticeable. It not only leads to a lack of water that is increasing in desert areas, but it must be kept in mind that the inhabitants of the villages located in the geographical areas whose access to water is difficult, make binding efforts to gain access to water. This article proposes to present the possibility of obtaining water by the condensation of the water vapors of the air by applying the thermodynamic processes of the humid air as well as those of the refrigerating installations. In fact, atmospheric air contains suspended water vapors. When this steam cools below its rose point, there is condensation if water vapors and liquid water or ice appears. It was obtained a quantity of condensed vapors in a refrigeration facility. This amount is directly proportional to the refrigeration power whose efficiency can be improved by the use of photovoltaic energy given the reduced financial cost of this energy. This seems to be a hope among the possible solutions to be considered for the resolution of the water issue.

关键词： Refrigeration Installation Satured Wet Air Condensed Vapors dew Temperature

Analysis and optimal synthesis of single loop spatial mechanisms

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2011年第9期12卷 665-679页

作者： Med Amine LARIBI Lotfi ROMDHANE Sad ZEGHLOUL Laboratoire de Génie Mécanique LAB-MA-05 Ecole Nationale d'Ingénieurs de Sousse Institut Pprime-UPR 3346 CNRS-Université de Poitiers-ENSMA Département Génie Mécanique et Systémes Complexes SP2MIBP30179 86962 Futuroscope France

In this work, a systematic approach is presented to obtain the input-output equations of a single loop 4-bar spatial mechanisms. The dialytic method along with denavit-Hartenberg parameters can be used to obtain these equations efficiently. A genetic algorithm （GA） has been used to solve the problem of spatial mechanisms synthesis. Two types of mechanisms, e.g., RSCR and RSPC （R： revolute; S： spherical; C： cylindrical; P： prismatic）, have illustrated the application of the GA to solve the problem of function generation and path generation. In some cases, the GA method becomes trapped in a local minimum. A combined GA-fuzzy logic （GA-FL） method is then used to improve the final result. The results show that GAs, combined with an adequate description of the mechanism, are well suited for spatial mechanism synthesis problems and have neither difficulties inherent to the choice of the initial feasible guess, nor a problem of convergence, as it is the case for deterministic methods.

关键词： Spatial mechanisms Genetic algorithm-fuzzy logic (GA-FL) method denevit-Hartenberg parameters Mechanism synthesis

Law of Distribution of Quantities of Shells on Togolese Littoral

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Open Journal of Civil Engineering 2020年第1期10卷 69-82页

作者： Kossi Bollanigni Amey ecole nationale supérieure d’Ingénieurs de l’université de Lomé Lomé Togo Equipe de Recherche et Développement de FORMATEC Lomé Togo

This study aims at analyzing the repartition of the quantities of shells of sand sediments of Togolese littoral, and at determining the law underlying their longitudinal and transversal distributions. Samples (210), collected all along Togolese littoral starting from Togo-Ghana border up to Togo-Benin border, are subject to the test of sieving. Each refusal on sieve is tested against construction of shells by hydrochloric acid. The determination of the quantity of shells according to their size and to longitudinal and transversal distributions on the littoral is completed. As a conclusion, the quantity of shells in the sediments is getting lower and lower starting from the aerial mid-beach (14.2%) to the mid-foreshore (11.80%), and getting higher and higher from the mid-foreshore (11.80%) to the low-foreshore (13.32%). It is getting lower and lower according to the direction of sediments’ transportations. This quantity of shells is high (40.87%) in the fine-grained sands (Ø Ø > 2 mm) and low (>24.26%) in the average-grained sands (0.125 mm ≤ Ø ≤ 2 mm). The average quantity of shells of 12.67% is lower than the recommended maximum quantity (30%) for the sands used for concrete. Thus, for the concrete works, the littoral sands might be seen as useful since they are granulating for concrete.

关键词： Sediment Togolese Littoral Quantity of Shells Distribution

Continuous frequency and phase spectrograms: a study of their 2D and 3D capabilities and application to musical signal analysis

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2008年第2期9卷 199-206页

作者： Laurent NAVARRO Guy COURBEBAISSE Jean-Charles PINOLI ecole nationale supérieure des Mines de Saint-Etienne Centre Ingénierie et Santé (CIS) and LPMG UMR 5148 CNRS 158 cours Fauriel 42023 Saint-Etienne cedex 2 France Medical Imaging Research Center (CREATIS-LRMN) UMR 5220 CNRS U630 INSERM Université Lyon 1 INSA Lyon Bat. Blaise Pascal 7 Av. Jean Capelle 69621 Villeurbanne France

A new lighting and enlargement on phase spectrogram （PS） and frequency spectrogram （FS） is presented in this paper. These representations result from the coupling of power spectrogram and short time Fourier transform （STFT）. The main contribution is the construction of the 3D phase spectrogram （3DPS） and the 3D frequency spectrogram （3DFS）. These new tools allow such specific test signals as small slope linear chirp, phase jump case of musical signal analysis is reported. The main objective is to and small frequency jump to be analyzed. An application detect small frequency and phase variations in order to characterize each type of sound attack without losing the amplitude information given by power spectrogram

关键词： Frequency spectrogram (FS) Phase spectrogram (PS) Time-frequency representations Musical signals