Free poset algebras and combinatorics of cones

In Free poset Boolean algebra F(P ), uniqueness of normal form of non-zero elements is proved and the notion of support of a non-zero element is, therefore, well defined. An Inclusion–Exclusion-like formula is given by defining, for each non-zero element x, using support of x ∈F(P ) in a very natural way.      

Firing behavior of argillites from northern Tunisia as raw materials for ceramic applications

This study reports the firing properties of clayey materials from northern Tunisia to evaluate their possible use as raw material in ceramic. Physical, chemical, and mineralogical characterization and thermal behavior were carried out by inductively coupled plasma atomic emission, X-ray diffraction, Fourier transform infrared spectroscopy, differential thermal analysis, particle size distribution, and Atterberg limits tests. Firing properties were evaluated by color, firing shrinkage, water absorption, bulk density, apparent porosity, and flexural strength. Studied clayey materials are made up mainly by kaolinite and illite and are rich in iron. The main transformations after thermal analysis were identified from 500°C to 1000°C subsequent to the dehydroxylation of clay minerals, calcite decomposition, and the recrystallization process. Fired samples up to 1100°C showed better physical and mechanical properties related with a great densification resulting in a significant increase in linear shrinkage, bulk density, and flexural strength and a decrease in apparent porosity and water absorption up to 1100°C. This behavior is due to a crystalline and liquid phases formed at low firing temperature associated with a high content of fluxing agents. The fired ceramic materials exhibited low water absorption up to 2.26% and high flexural strength up to 32.6 MPa, which makes their potential use for some earthenware and stoneware products.     

Development and Characterization of Peptidic Fusion Inhibitors Derived from HIV‐1 gp41 with Partial D‐Amino Acid Substitutions

Interactions between C34 and N36 : Synthetic peptides with D ‐amino acid substitutions that mimic the human immunodeficiency virus (HIV) gp41 HR2 region may lead to new peptidic anti‐HIV‐1 drugs that retain potent antiviral activity while being more resistant to proteolytic degradation.

     

Azo dyes decolourization by the laccase from Trametes trogii

Dye decolourizing potential of laccase obtained from the white rot fungus Trametes trogii was studied for two reactive dyes; namely Reactive Black 5 (diazoic) and Reactive Violet 5 (monoazoic). The presence of a redox mediator as 1-hydroxybenzotriazole (HBT) was found to be essential for the decolourization of the said two dyes. The optimization of the decolourization process using experimental design was studied with three variables: dye (25, 50, 100 mg/L), enzyme (0.1; 0.5; 1 U/mL) and redox mediator (0.1; 0.5; 1 mM) concentrations. Results of this investigation revealed that the optimum concentrations of dye, enzyme and HBT for the degradation of the Reactive Black 5 (RB5) were 25 mg/L, 1U/mL and 1 mM, respectively, for a maximum decolourization about 93%. However, the optimum concentrations for Reactive Violet 5 (RV5) were found to be 25 mg/L, 0.5 U/mL and 0.5 mM, for a total removal of the dye. The apparent capacity of this laccase to decolourize azo dyes make it a suitable candidate for further applications in biobleaching and the treatment of textile effluents.     

Study of RF N LDMOS critical electrical parameter drifts after a thermal and electrical ageing in pulsed RF

An innovative reliability test bench dedicated to RF power devices is currently implemented. This bench allows to apply both electric and thermal stress for lifetime test under radar pulsed RF conditions. This paper presents the first investigation findings of critical electrical parameter degradations after thermal and electrical ageing. It shows that the tracking of a set of parameters (drain–source current, on-state resistance, threshold voltage, feedback capacitance and transconductance) can give insight into the hot carrier injection phenomenon for a RF n⁻ channel lateral DMOS (N⁻ LDMOS) working under pulsed conditions.     

Cellular reuse patterns quality and efficiency comparison

Capacity enhancement and interference performance are among the most important issues in the 2nd and 3rd generation cellular networks planning. The main objective of the planning process is to reach a tradeoff between the quality and the capacity of the network. In this paper, we study and compare the CIR and spectral efficiency of different cellular reuse patterns. We also establish the exact analytical PDF expression of CIR assuming one interferer in the serving cell, we then generalize this expression to many interferer tiers. Shadowing effect is also carefully considered in the CIR distribution extension. Moreover, numerical computations are performed to estimate spectral efficiency values for the different patterns studied. Some simulations are also developed to give the comparison a concrete and a practical aspect. A reuse partitioning (RP) capacity scheme is used to serve as the basis of the study. In particular, RP sub‐cells' sizes and number of partitions are optimized in order to maximize the traffic capacity parameterized by spectral and trunking efficiency while involving the financial cost. The efficiency/cost comparison is among the main novel issues contributed by the paper. Copyright © 2006 John Wiley & Sons, Ltd.     

Nutritional characteristics,biochemical composition and antioxidant activities of Moroccan Oat varieties

Oat has been recognized as a healthy food for a long time. In this study, physicochemical analysis including, moisture, pH, ash, fibres, proteins, starch, carbohydrates, some minerals, sugars, fatty acids, sterols, total phenolic, and flavonoid contents of four Moroccan Oat varieties (Amlal, Tissir, Zahri and Ghali) were investigated. Additionally, starch morphology has been described according to scanning electron microscopy, and viscosity as measured on a rotary rheometer, increased with stabilization time. Furthermore, Oat extracts were analyzed with regard to their antioxidant activities using DPPH radicals’ cation, Trolox equivalent antioxidant capacity and ferric reducing/antioxidant power. Results from this investigation demonstrated that Moroccan Oat varieties constitute an interesting supplement of natural antioxidants, especially phenolic compounds. Moreover, potassium was the main mineral in Oat seeds (1628.17–2541.52 mg/Kg); also, the oleic, linoleic, and palmitic acids were the dominant fatty acids. While the major sterols were, β-sitosterol, Δ-5-avenasterol and campesterol. Finally, sugar analysis by HPLC-RI indicate that sucrose content was higher than glucose and fructose respectively, and that Ghali and Amlal varieties exhibit an important total sugars levels. Those results highlight the possible contributions of Oat seeds to nutritional therapy.     

Predicting Motorway Traffic Performance by Data Fusion of Local Sensor Data and Electronic Toll Collection Data

Abstract: This article proposes data fusion from different sources to improve estimation and prediction accuracy of traffic states on motorways. This is demonstrated in two case studies on an intraurban and an interurban motorway section in Austria. Data fusion in this case combines local detector data and speed data from the Electronic Toll Collection (ETC) system for heavy goods vehicles (HGV). A macroscopic model for open motorway sections has been used to estimate passenger car and HGV density, applying a standard state‐space model and a linear Kalman filter. The resulting historical database of 4 months of speed‐density patterns has been used as a basis for pattern recognition. A nonparametric kernel predictor with memory length of 9 and 18 hours has been used to predict HGV speed for a prediction horizon of 15 minutes to 2 hours. Results show good overall prediction accuracy. Correlation analysis showed little bias of predicted speed for free flow and congested time intervals, whereas transition states between free flow and congestion were frequently biased. Prediction accuracy can be improved by applying a combination of different prediction methods. On the other hand, computational performance of the prediction has to be further improved prior to implementation in a traffic management center.     

Growth temperature impact on MOVPE-grown BInGaAs/GaAs QWs designed for optoelectronic applications

Journal of Materials Science: Materials in Electronics - In this work, quaternary BInGaAs single quantum wells have been grown on GaAs substrate by metal–organic vapor-phase epitaxy. The...     

Long-term bond performance of GFRP bars in concrete under temperature ranging from 20 °C to 80 °C

Eighty pull-out specimens were used to study the effect of temperature ranging from 20 °C to 80 °C in dry environment on bond properties between Glass Fiber Reinforced Polymer (GFRP) bars and concrete. The pullout-test specimens were subjected during 4 and 8 months to high temperatures up to 80 °C and then compared to untreated specimens (20 °C). Experimental results showed no significant reduction on bond strength for temperatures up to 60 °C. However, a maximum of 14% reduction of the bond strength was observed for 80 °C temperature after 8 months of thermal loading. For treated specimens, the coefficient β in the CMR model, which predicts the bond–stress–displacement behavior, seems to be dependant with the temperature.