Assessment of Equity and Adequacy of Water Delivery in Irrigation Systems Using Remote Sensing-Based Indicators in Semi-Arid Region, Morocco

The irrigation performance criteria of equity and adequacy are of primary concern for irrigation managers. The input data required at various scales to assess irrigation performance, often not available, need costly intensive field campaigns. Remote sensing techniques, used to directly estimate crop evapotranspiration (ETc), became recently an attractive option to assess irrigation performance from individual fields to irrigation scheme or river basin scale. In this study, ETc maps were obtained by combining the FAO-56 dual approach with relationships between crop biophysical variables and NDVI (Normalized Difference Vegetation Index), using high spatial resolution time series of SPOT and Landsat images. This approach was applied for 2002/2003 growing season in Haouz plain, Morocco. Remote sensing-based indicators, reflecting equity and adequacy of the irrigation water delivery were estimated. Adequacy was determined according to Relative Irrigation supply (RIS), Depleted Fraction (DF) and Relative Evapotranspiration (RET) and equity according to the coefficient of variation of ETc. The analysis of these indicators exhibits a great variability among fields. Variability in irrigation performance at all levels, associated factors and possible improvements are discussed. This study demonstrates how remote sensing-based estimates of water consumption provide better estimates of irrigation performance at different scales than the traditional field survey methods.     

Linear and quadratic solid–shell finite elements SHB8PSE and SHB20E for the modeling of piezoelectric sandwich structures

In this article, hexahedral piezoelectric solid–shell finite element formulations with linear and quadratic interpolation, denoted by SHB8PSE and SHB20E, respectively, are proposed for the modeling of piezoelectric sandwich structures. Compared to conventional solid and shell elements, the solid–shell concept reveals to be very attractive, due to a number of well-established advantages and computational capabilities. More specifically, the present study is devoted to the modeling and analysis of multilayer structures that incorporate piezoelectric materials in the form of layers or patches. The interest in this solid–shell approach is shown through a set of selective and representative benchmark problems. These include numerical tests applied to various configurations of beam, plate and shell structures, both in static and vibration analysis. The results yielded by the proposed formulations are compared with those given by state-of-the-art piezoelectric elements available in ABAQUS, in particular, the C3D20E quadratic hexahedral finite element with piezoelectric degrees of freedom.     

PLA/SiO2 composites: Influence of the filler modifications on the morphology,crystallization behavior,and mechanical properties

Films of an architecturally modified poly(lactic acid) (PLA_REx) with three different types of fumed silica nanofillers (SiO₂) were processed through reactive extrusion‐calendering in a pilot plant. The effects of the SiO₂ type on both the dispersion and the crystallization behavior under dynamic and isothermal conditions are investigated using transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). The mechanical properties are assessed by tensile testing. TEM micrographs showed that the improved chemical affinity of both surface‐treated SiO₂ toward PLA_REx end groups did not improve particle dispersion. DSC results revealed that untreated SiO₂ nucleated PLA_REx more efficiently than both surface‐modified silicas. The activation energy for the isothermal crystallization process, as determined by an Arrhenius method, suggests that addition of untreated SiO₂ enhances the crystallization rate of PLA_REx. However, it seems that the tensile behavior remained unchanged whether silicas were added or not. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45367.     

Carrier compensation and activation energy studies in pyrolytic In2O3 thin film

The thermal activation energies of polycrystalline thin films of In₂O₃ on a glass substrate have been studied by a post deposition heat treatment in the temperature range 30 to 240 C in air. The temperature dependence behaviour of the film and the various activation energies obtained have been explained by taking the existing grain boundary trapping models and other semiconductor models into account. It has been concluded however that at temperatures above 190C a dissociative chemisorption process may become active in the film and partially compensate the carriers generated for electrical conduction.     

Application of practical fuzzy arithmetic to fuzzy internal model control

This paper applies a new fuzzy arithmetic of interval calculus and fuzzy quantities to automatic control. Practical results are obtained which overcome those based on the extension principle or α-cuts. The proposed approach is based on a different representation of fuzzy numbers, though most common arithmetic operators cannot be directly applied for designing a fuzzy controller due to the unjustified overestimation effect. To avoid this phenomenon, a procedure based on an “exact” resolution calculus is proposed, whose solutions allow creating a fuzzy internal model control scheme. The validity of the new method is illustrated by a real-time educational engineering application on classical control design: a coupled tanks system.     

Optical and nuclear characterization of Xe-induced nanoporosity in SiO2

We performed RBS, infrared (IR) and C-V measurements in order to follow the evolution of Xe, bubbles/cavities and other defects (with a focus on NBOHC: non-bridging oxygen hole center) and dielectric constant (k), in high dose Xe implantation in SiO₂. As-implanted sample provides the lowest value of k which increases with post thermal annealing. In the meantime, the concentration of negatively charged defects decreases with annealing while Xe out-diffuses after annealing at 1100 °C leaving Xe free cavities in the sample. By combining these results one can determine the contribution of nanoporosity in dielectric constant evolution.     

Effect of protein hydrolysates from sardinelle (Sardinella aurita) on the oxidative status and blood lipid profile of cholesterol-fed rats

This study was designed to test the hypolipidemic properties and antioxidative activities of sardinelle (Sardinella aurita) protein hydrolysates (SPHs) obtained by treatment with crude enzyme preparations from Bacillus pumilus A1(SPHA1), Bacillus mojavensis A21(SPHA21) and crude enzyme extract from sardinelle viscera (SPHEE).Wistar rats were fed during 7 weeks a standard laboratory diet, a cholesterol-enriched diet (1%) or a cholesterol SPH-enriched diet. The hypercholesterolemic diet induced the elevation of total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C). Supplementing cholesterol-enriched diet with SPHs or whole sardinelle protein (WSP) at a concentration of 5% (w/w) increased the serum level of high-density lipoprotein cholesterol (HDL-C) and HDL-C/TC ratio and decreased the serum levels of TC, TG, LDL-C and LDL-C/HDL-C ratio significantly.The thiobarbituric acid-reactive substances (TBARS) level, as an indicator of lipid peroxidation, and the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were examined. The hepatic antioxidant enzymes activities were significantly decreased and the malondialdehyde (MDA) level was increased in rats fed a cholesterol-enriched diet compared to those fed a standard diet. The treatment of hypercholesterolemic (HCD) diet rats with SPHs reduced the MDA concentration and increased the antioxidant enzyme activities.These results suggested that the hypolipidemic effect of SPHs might be due to their abilities to lower serum TC, TG, and LDL-C levels as well as to their antioxidant activities preventing the lipid peroxidation process.     

Atomic Layer Deposition on Bulk Quantities of Surfactant-Modified Single-Walled Carbon Nanotubes

Atomic layer deposition (ALD) on single-walled carbon nanotubes (SWNTs) can be achieved through physical surface modification using liquid-phase pretreatment dispersion techniques. Al₂O₃ ALD on nonfunctionalized SWNTs produced isolated nodule growth. Ethanol and sodium dodecylsulfate (SDS) pretreatment methods were utilized to disperse and functionalize batches of nanotube powders. Ethanol-based dispersion techniques provided hydroxylated surfaces that promoted continuous Al₂O₃ films on SWNT surfaces. The SDS method provided a dense nucleation site pattern that allowed for conformal Al₂O₃ film growth. Al₂O₃ ALD processes yielded growth rates of 0.13 nm/cycle, independent of the functionalization technique, at 450 K. X-ray photoelectron spectroscopy was used to quantify the composition of the films, which were amorphous as deposited. A surfactant-assisted ALD mechanism is proposed, which retains a physisorbed micelle structure as a template for the dense precursor nucleation site pattern. Liquid-phase pretreatment was found to be an efficient mechanism to overcome attractive forces associated with nanoscale particle systems, and significantly reduced the size of nanotube bundles. The successful ALD on an individual suspended nanotube in other work was extended to the bulk coating of SWNT powders. This work demonstrates significant progress toward the goal of producing commercially viable SWNT-based nanocomposite devices that incorporate bulk quantities of ALD-functionalized nanotubes.     

Parallel matrix factorization-based collaborative sparsity and smooth prior for estimating missing values in multidimensional data

Pattern Analysis and Applications - Parallel matrix factorization has recently emerged as a powerful tool for low-rank tensor recovery problems. However, using only the low-rank property is often...     

Study of Rust Effect on the Corrosion Behavior of Reinforcement Steel Using Impedance Spectroscopy

Most studies on corrosion of steel reinforcement in concrete are conducted on steel samples with polished surface (free of all oxides) in order to reproduce the same experimental conditions. However, before embedding in concrete, the steel bars are often covered with natural oxides (rust), which are formed during exposure to the atmosphere. The presence of this rust may affect the electrochemical behavior of steel rebar in concrete. In order to understand the effect of rust on the corrosion behavior of reinforcement steel, potentiodynamic and electrochemical impedance spectroscopy (EIS) tests were carried out in a simulated concrete pore solution using steel samples with two different surface conditions: polished and rusted samples. The obtained results have shown that the presence of rust on the steel bar has a negative effect on its corrosion behavior, with or without the presence of chlorides. This detrimental effect can be explained by the fact that the rust provokes a decrease of the electrolyte resistance at the metal-concrete interface and reduces the repassivating ability. In addition, the rust layer acts as a barrier against the hydroxyl ion diffusion, which prevents the realkalinization phenomenon.