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Use of soft computing techniques for tunneling optimization of tunnel boring machines

Underground Space 2021年第3期6卷 233-239页

作者： Isam Shahrour Wengang Zhang College of Civil Engineering Tongji UniversityShanghai 200092China laboratoire Genie Civil et geo-environnement Universite de LilleFrance School of Civil Engineering Chongqing UniversityChina

Thanks to advances in tunnel boring machine(TBM)and monitoring,significant progress has been achieved in the application of soft computing techniques for the optimization of TBM tunneling and the reduction of disturbance related to tunneling in urban *** experimental,analytical,and numerical methods have limitations in solving problems related to TBM tunneling,engineers can use soft computing techniques in analyzing the relationship between the target tunneling responses and influential design inputs parameters,including the geometrical,geological,and TBM operational *** techniques are useful in achieving robust and low-cost ***,engineers face difficulties in making an optimal choice of the soft computing technique to solve the complex problems related to TBM *** help with this choice,this study presents state of the art about the use of soft computing techniques in TBM tunneling through practical *** study proposes recommendations for the optimal use of these techniques,in particular(i)the importance of preliminary analyses for the selection and reduction of input parameters,(ii)the necessity to complete insufficient data using laboratory tests and numerical modeling,(iii)the selection of reduced number of hidden layers and nodes to avoid overfitting,(iv)the use of recurrent neural networks to deal with time-series data,and(v)the association of soft computing methods with hybrid optimization techniques to reduce the risk of convergence to local minima.

关键词： Soft computing Tunneling Tunnel boring machine Artificial neural network Machine learning Optimization Settlement Convergence Artificial intelligence

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defluoridation of groundwater by calcined Mg/Al layered double hydroxide

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Emerging Contaminants 2016年第1期2卷 42-48页

作者： A.Elhalil S.Qourzal F.Z.Mahjoubi R.Elmoubarki M.Farnane H.Tounsadi M.Sadiq M.Abdennouri N.Barka Univ Hassan 1 Laboratoire des Sciences des Matéeriauxdes Milieux et de la Modélisation(LS3M)BP.14525000 KhouribgaMorocco Equipe de matériaux Photocatalyse et EnvironnementDépartement de ChimieFacultédes SciencesUniversitéIbn ZohrB.P.8106 CitéDakhlaAgadirMorocco

The present study evaluated calcined Mg/Al layered double hydroxide(CLDH)availability for the removal of fluoride from local *** Mg/Al layered double hydroxide(LDH)was synthesized by coprecipitation method and characterized by XRD,FT-IR and TGA-TDA *** defluoridation experiments were performed under various conditions such as calcination,solution pH,contact time,temperature,material dosage and *** results indicate that fluoride removal strongly increased after calcination of the LDH up to 600℃.The maximum fluoride removal was obtained at solution pH of *** of fluoride removal followed the pseudo-second order kinetic *** rise in solution temperature strongly enhances the removal *** adsorption mechanism involved surface adsorption,ion exchange interaction and original LDH structure reconstruction by rehydration of mixed metal oxides and concomitant intercalation of fluoride ions into the interlayer *** optimum dosages required to meet the national standard for drinking water quality were found to be 0.29 and 0.8 g/L,respectively,for Bejaad and Settat goundwaters.A decrease in the fluoride uptake with increasing the number of regeneration cycles was observed.

关键词： Fluoride removal Groundwater Layered double hydroxide Drinking water quality

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Photocatalytic degradation of 4-chlorophenol under P-modified TiO2/UV system: Kinetics, intermediates, phytotoxicity and acute toxicity

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Journal of Environmental Sciences 2012年第3期24卷 479-487页

作者： Kais Elghniji Olfa Hentati Najwa Mlaik Ayman Mahfoudh Mohamed Ksibi University of Sfax Laboratoire EauEnergie et Environnement ENISB.P 11733038 SfaxTunisia Institut Supe'rieur de Biotechnologie de Sfax B.P 1175 3038 SfaxTunisia

A series of phosphorus-modified titanium dioxide samples with varying P/Ti atomic ratio were conveniently prepared via a conventional solgel route. The effects of phosphorus content and calcination temperature on the crystalline structure, grain growth, surface area, and the photocatalytic activity of P-modified TiO2 were investigated. The XRD results showed that P species slow down the particle growth of anatase and increase the anatase-to-rutile phase transformation temperature to more than 900°C. Kinetic studies on the P-modified TiO2 to degraded 4-chlorophenol had found that the TP5500 prepared by adopting a P/Ti atomic ratio equal to 0.05 and calcined at 500°C had an apparent rate constant equal to 0.0075 min 1, which is superior to the performance of a commercial photocatalyst degussa P25 Kapp = 0.0045 min 1 and of unmodified TiO2 （TP0500） Kapp = 0.0022 min 1. From HPLC analyses, various hydroxylated intermediates formed during oxidation had been identified, including hydroquinone （HQ）, benzoquinone （BQ） and （4CC） 4-chlorocatechol as main products. Phytotoxicity was assessed before and after irradiation against seed germination of tomato （Lycopersicon esculentum） whereas acute toxicity was assessed by using Folsomia candida as the test organism. Intermediates products were all less toxic than 4-chlorophenol and a significant removal of the overall toxicity was accomplished

关键词： P-modified TiO2 photocatalyst 4-chlorophenol acute toxicity germination

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Assessment of Radon Concentrations inside Residential Buildings and Estimation of the Dose in the City of Kaya, Burkina Faso

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Open Journal of Applied Sciences 2023年第7期13卷 1066-1078页

作者： Wend-Yam Appolinaire Elola Telado Luc Bambara Ali Doumounia Nièssan Kohio Soumaila Ouédraogo François Zougmore laboratoire de matériaux et environnement Université Joseph Ki-Zerbo Burkina Faso Institut des Sciences et de Technologie Ecole Normale Supérieure Burkina Faso

Colorless, incessant radon gas is notably the second most important cause of lung cancer after smoking in smokers and the first cause in non-smokers. Having little effect in the atmosphere, radon gas accumulates in confined spaces. Therefore, the determination of radon concentrations inside residential buildings is very important to improve the health of the inhabitants. The objective of this research is to measure the concentration of radon in indoor air in residential areas of the city of Kaya and to assess the absorbed dose, the effective dose and the relative risk of lung cancer. In this study, the CORENTIUM AIR THINGS digital radon detector is used to determine the radon concentration in twenty-one houses in Kaya. The CORENTIUM AIR THINGS digital radon detector has been placed in each residential building for a minimum period of one week and the concentration values are read every 24 hours. This research revealed that the average concentration of radon was 28.47 Bq/m3 in the residential areas of Kaya. The radon concentration in a house has been found to exceed 100 Bq/m3, which is the level authorized by the World Health Organization (WHO). In the long term, the absorbed dose varies from 0.118 mSv to 4.975 mSv and the effective dose is between 0.229 mSv and 12.002 mSv. In the short term, the absorbed dose varies between 0.095 mSv to 5.001 mSv and the effective dose is between 0.283 mSv to 11.935 mSv. The mean lung cancer relative risk (CPRR) from indoor exposure was 1.026. There is a need to raise awareness among the population of the city of Kaya on this issue and to take measures to reduce radon in homes when the concentrations are above the limit recommended by the WHO.

关键词： Radon Concentration Dose Relative Risk Lung Cancer

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Analogy between adsorption and sorption： An elementary mechanistic approach. I. Monolayer adsorption and sorption without solvent cluster formation

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Chinese Journal of Chemical Engineering 2017年第12期25卷 1740-1749页

作者： Pierre Schaetzel Sébastien Thomas Hasna Louahlia Gualous laboratoire Universitaire des Sciences Appliquées de Cherbourg Université de Caen IUT de Caen Boulevard Marechal Juin 14032 Caen cedex France Institut de chimie et procédés pour l'énergie l'environnement et la santé Université de Strasbourg 25 rue Becquerel 67087 Strasbourg cedex 2 France

The elementary mechanistic model of adsorption and sorption is based on a simple hypothesis： the adsorption sites are uniformly distnbuted on the surface of the pore walls in the adsorbent, the sorption sites are uniformly distributed in the volume of the polymer. In this first paper we will analyze the simple case where one solute molecule is only allowed to occupy a single adsorption or sorption site. A common elementary occupation law of the free sites is assumed： the differential increase of the number of the adsorbed/sorbed molecules is proportional to the differential increase of the activity of the solute and the concentration of the free （non-occupied） sites in the solid. The proportionality coefficient is called affinity coefficient depending on the solid/solute couple and on the temperature and independent of the concentration of the solute. In adsorption the concentration of the free sites is a surface concentration on the pore walls and in sorption it is expressed by the molarity. The simple monolayer adsorption law of Jovanovic is obtained： n = no（1 - e KP） where n is the number of moles adsorbed when the pressure is P. no is the total number of adsorption sites and K the affinity coefficient for adsorption. The sorption law writes： a = 1/k [Ф/1-Ф] ＋ 1-r/k In [1 ＋ 1/r Ф/1-Ф] where Ф, r and k hold respectively for the volume fraction of the solvent in the polymer, for the ratio of the molar volumes of the solvent to the elementary polymer chain containing one single adsorption site and for the sorption affinity coefficient. The confrontation of these equations to experimental isotherms is satisfactory in comparison with the classical Langmuir and Flory-Huggins equations： the best results are obtained for adsorption of vapors on a 5A zeolite and for all analyzed sorption results.

关键词： Adsorption isotherms Sorption isotherms Flory-Huggins theory Langmuir equation

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Investigation of structural parameters and self-aggregation of Algerian asphaltenes in organic solvents

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Petroleum Science 2015年第3期12卷 509-517页

作者： Asma Larbi Mortada Daaou Abassia Faraoun laboratoire de Synthèse organique Physico-chimieBiomolcules et Environnement (LSPBE)Department of Industrial Organic ChemistryFaculty of ChemistryUniversity of Sciences and Technology of Oran laboratoire de Chimie Physique Macromoléculaire (LCPM) Department of ChemistryFaculty of SciencesUniversity of Oran

Elemental analysis, Fourier transform infrared （FTIR）, 1H-NMR, fluorescence spectroscopy, and surface tension methods have been used to characterize the molecular structure and the aggregation behaviors of two asphaltenic fractions derived, respectively, from an Alge- rian petroleum well and a corresponding storage tank deposit. Elemental analysis, FTIR, ~H-NMR, and fluores- cence spectroscopy were used to investigate the chemical composition and structural parameters of asphaltenes, while the surface tension method was used to measure the critical micelle concentration （CMC） in organic solvents with different solubility parameters and polarities in order to characterize the asphaltenes＇ aggregation behaviors. Results show that the unstable asphaltenes fraction extracted from the storage tank deposit possesses a higher polarity （higher heteroatoms content） and a lower aro- maticity than stable asphaltenes from the petroleum well. The CMC results indicate that asphaltenes with high polarity and low aromaticity have a high solubility in polar solvents such as nitrobenzene, whereas asphaltenes with low polarity and high aromaticity are more soluble in solvents with weak polarity, like toluene. It is concludedthat the difference of structure of asphaltene samples and polarity of solvents can lead to difference of aggregation behaviors.

关键词： Asphaltenes Algerian petroleum Structural parameters - CMC

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Soil Contamination due to E-Waste Disposal and Recycling Activities: A Review with Special Focus on China

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Pedosphere 2012年第4期22卷 470-488页

作者： G. ECHEVARRIA T. STERCKEMAN M. O. SIMONNOT J. L. MOREL INPL(ENSAIA)/INRA Laboratoire Sols et Environnement 2 Avenue de la For et de Haye BP 172 54505 Vandoeuvre-lès-Nancy Cedex (France) laboratoire Réactions et Génie des Procédés (LRGP) Université de Lorraine-CNRS (UPR 3349) 1 Rue Grandville BP20451 54001 Nancy Cedex (France)

Considering that even contaminated soils are a potential resource for agricultural production, it is essential to develop a set of cropping systems to allow a safe and sustainable agriculture on contaminated lands while avoiding any transfer of toxic trace elements to the food chain. In this review, three main strategies, i.e., phytoexclusion, phytostabilization, and phytoextraction, are proposed to establish cropping systems for production of edible and non-edible plants, and for extraction of elements for industrial use. For safe production of food crops, the selection of low-accumulating plants/cultivars and the application of soil amendments are of vital importance. Phytostabilization using non-food energy and fiber plants can provide additional renewable energy sources and economic benefit with minimum cost of agricultural measures. Phytoextracting trace elements （e.g., As, Cd, Ni, and Zn） using hyperaccumulator species is more suitable for slightly and moderately polluted sites, and phytomining of Ni from serpentine soils has shown a great potential to extract Ni-containing bio-ores of economic interests. We conclude that appropriate combinations of soil types, plant species/cultivars, and agronomic practices can restrict trace metal transfer to the food chain and/or extract energy and metals of industrial use and allow safe agricultural activities.

关键词： agronomic practices food safety hyperaccumulator phytoremediation trace element

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Direct oxidation of methane to oxygenates over heteropolyanions

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Journal of Natural Gas Chemistry 2008年第3期17卷 309-312页

作者： Ouarda Benlounes Sadia Mansouri Chérifa Rabia Smain Hocine laboratoire de Chimie Appliqueé et de Génie Chimique Université Mouloud Mammeri laboratoire de Chimie du Gaz Naturel Institut de Chimie USTHB

Partial oxidation of methane to formaldehyde and methanol was studied at atmospheric pressure in the temperature range of 700-750 °C using heteropolycompound catalysts （NH4）6HSiMo11FeO40, （NH4）4PMo11FeO39, and H4PMo11VO40, which were prepared and characterized by various analysis techniques such as infrared, visible UV, XRD and DTA. O2 or N2O was used as the oxidizing agent, and the principal products of the reaction were CH3OH, CH2O, CO, CO2, and water. The conversion and the selectivity of products depend strongly on the reaction temperature, the nature of oxidizing agent, and the composition of catalyst.

关键词： methane oxidation heteropolycompounds methanol oxygenates

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Optical Constant and Electrical Resistivity of Annealed Sn3Sb2S6 Thin Films

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Acta Metallurgica Sinica(English Letters) 2016年第3期29卷 287-294页

作者： Y.Fadhli A.Rabhi M.Kanzari laboratoire de Photovoltaique et materiaux Semi-conducteurs-ENIT BP 37 Le belvedere 1002 Tunis Tunisia laboratoire de Photovoltaiques et materiaux Semi-conducteurs-ENIT-IPEITunis Montfleury Universite de Tunis Tunis Tunisia

In this study,we report the annealing effects on the physical properties of Sn_3Sb_2S_6 thin ***_3Sb_2S_6 thin films were prepared onto non-heated glass substrates via thermal evaporation *** as-deposited films were annealed in air for 1 h in the temperature range from 100 to 300 °C.X-ray diffraction results show that the crystallinity of the thin films increased after *** microstructure parameters crystallite size,dislocation density,lattice strain and stacking fault probability were *** optical properties were obtained from the analysis of the experimental recorded transmittance and reflectance spectral data over the wavelength range 300–1800 *** absorption coefficient（10~5cm^（-1）） reached to the visible and near-IR spectral range.A decrease in optical band gap from 1.92 to 1.71 e V by increasing the air annealing temperature was *** energy E_o and dispersion energy E_d of the films after annealing were estimated according to the model of Wemple–Di Domenico single ***–Fan model was applied to determine the electron free carrier susceptibility and the ratio of carrier concentration to the effective *** layers annealed at temperatures 〉150 ℃ undergo abrupt changes in their electrical properties and exhibit a resistive hysteresis *** properties confer to the material interest perspectives for its application in diverse advanced technologies such as photovoltaic applications and optical storage.

关键词： Thin films Sn_3Sb_2S_6 Optical constants Resistivity Hysteresis

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Consideration of Size and Dimension in the Evaluation of Transfers during Convective Drying of Sweet Potato

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Journal of Analytical Sciences, Methods and Instrumentation 2020年第4期10卷 104-112页

作者： Abdou-Salam Ganame Kondia Honore Ouoba François Zougmore laboratoire des matériaux et environnement (LAME) Unité de Formation et de Recherche en Sciences Exactes et Appliquée (UFR/SEA) Université de Ouaga I Ouagadougou Burkina Faso

This work is interested in solving the complex problem of understanding mass transfers in biological media. The contribution of the initial sample size is taken into account. Transfers are established more efficiently in small samples. Thus, from the first 50 minutes, the cubic sample at 1 cm stop is already at 50% while the sample at 4 cm edge is at about 90% of its initial water content. Likewise the shape is combined with the size. But it is revealed that if we fix similar characteristic dimensions, we can bypass the notion of initial shape. Thus the cubic samples 4 cm of edges. 4 cm diameter of spherical shape, 4 cm × 4 cm height-diameter cylindrical one, all dry identically.

关键词： Mass Transfer Size Shape Agri-Food Products

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