A robust invariant bipolar representation for R 3 surfaces: applied to the face description

In this paper, we intend to introduce a novel invariant curved surface representation under the 3D motion group. It is constructed from the superposition of the two geodesic potentials generated from a given couple of surface points. By sampling this continuous representation, invariant points are extracted from a large neighborhood around these reference points. Different numerical methods are implemented in order to find an efficient approximation in the mean of the shape distance. The inference of small distortions of points positions applied to the reference points is analyzed. We apply the proposed representation to real 3D images. The experimentations are performed on the 3D facial database Bosphorus.     

An inexpensive and efficient method for the synthesis of BTO and STO at temperatures lower than 200 °C

During the past decade the reduction in size of functional architectures has been a dominating trend in many fields of science and technology. The search for electronic materials that can be cheaply solution-processed into nanopowders, while simultaneously providing quality device characteristics, represents a major challenge for material scientists. Solvothermal process is used in order to obtain fine nanoparticles of BaTiO₃ and SrTiO₃ at low temperatures by using an inorganic, ionic precursor. Rietveld refinement proves the presence of a mixture of 65% tetragonal and 35% cubic nanoparticles in the barium titanate powder with an average size of 73 nm and 67 nm, respectively. FTIR shows that an acid treatment allows the elimination of carbonate impurities.     

Preface to the VECoS 2018 special issue of ISSE

Innovations in Systems and Software Engineering -     

Prevalence and profile of renovascular disease in type II diabetic patients with severe hypertension

The aim of this study was to determine the prevalence and profile of renal artery stenosis (RAS) in NIDDM population with severe hypertension. 60 consecutive NIDDM with severe HT (> or = 3 hypotensive drugs), 42 F/18 M (SR: 2.8), mean age: 66.6 +/- 6.5 years, diabetes duration: 14.1 +/- 6 years have had metabolic, ABPM and renal investigations: color duplex scan (CDS) (with renal us): n = 60, and/or arteriography: n = 17). 13 (21.5%) renal artery stenosis > or = 70%: 8 unilateral/5 bilateral were proved by arteriography. We compared classic HT (n = 47) versus renovascular HT (n = 13). There was no difference for age (years): 64.8 +/- 8 versus 70.6 +/- 6.4, HT duration (years): 11.6 +/- 6.8 versus 12.3 +/- 6. B.M.I.: 31.5 +/- 6 versus 27.6 +/- 3.3, HBA1C (%): 8.9 +/- 2.2 versus 8.8 +/- 0.9, cholesterol (mmol/L): 5.7 +/- 1.3 versus 5.5 +/- 0.6. Significant difference (p < 0.05) was noticed for S.R. (F/M): 2.9 versus 1.16, diabetes duration (years): 11.7 +/- 5 versus 16.5 +/- 8, frequency of retinopathy (%): 30 versus 61, smoking (%): 10 versus 40, triglycerides (mmol/L): 1.9 +/- 1.1 versus 2.6 +/- 1.1, and (p < 0.01) for blood pressure level (mmHg) (SBP: 142 +/- 20 vs 155 +/- 7, DBP: 81 +/- 13 vs 87 +/- 10, MBP: 103 +/- 16 vs 111 +/- 6), frequency (%) of HT escape (> or = 140/SBP, > or = 90/DBP) on ABPM: 40 versus 75 and 24 versus 40, insulin requirence (%): 36 versus 69, macroangiopathy (%): 51 versus 100 (coronaropathy: 34 vs 61, legs arteritis: 21 vs 69, carotid stenosis: 17 vs 30) and for renal function: frequency (%) of micro-macroalbuminuria: 36 versus 92 creatinaemia (mmol/L): 80 +/- 24 versus 124 +/- 44, creatinaemia clearance (mmL/min): 65 +/- 30 versus 40 +/- 12 while are found 5 renal insufficiencies (> or = 120 mmol/L). In NIDDM population with severe HT, renovascular HT is frequent (21.5%), and RAS must be evocated in unstable HT and/or renal injury with macro angiopathy, old NIDDM (> 15 years), requiring insulin. Colour duplex scan (+ renal US) mays lead to arteriography to confirm renal artery stenosis.     

Selection of dispersants for the dispersion of carbon black in organic medium

The dispersion of the carbon black pigment in non-aqueous medium requires the use of dispersant additives. Two carboxylic dispersants of different chemical nature and molar masses have been investigated regarding this purpose. Their adsorption behavior has been evaluated by means of adsorption isotherms. The molecular interactions taking place at the surface have been inferred from IR and ¹³C RMN spectroscopies. The rheological behavior of the dispersions has considerably been improved by the presence of the copolymer dispersant of higher molar mass. It might adsorb at the surface by hydrogen bindings while taking a flat conformation with tails and possibly few loops that contributed to the steric stabilization of particles. The consequences of the deflocculation of the suspension on the colorimetric properties are an enhanced tinting strength and improved color stability.     

Dynamic accumulation of 4-desmethylsterols and phytostanols during ripening of Tunisian Meski olives (Olea europea L.)

Eleven 4-desmethylsterols and two phytostanols were identified by GC–MS during the ripening of Meski olive. The maximum levels of 4-desmethylsterols (1300 mg/100 g oil) and phytostanols (7.5 mg/100 g oil) were reached at the 26th week after the flowering date (WAFD) of fruit. β-Sitosterol (72–86% of total 4-desmethylsterols) was the major 4-desmethylsterols during the maturity of fruit, while sitostanol was the predominant phytostanols (75–85% of total phytostanols). Δ5-Avenasterol (2–18%) and campesterol (1.6–4%) were the second and the third 4-desmethylsterol levels detected, respectively, during the ripening of Meski olive. The levels of campestanol varied from 15% to 25% of phytostanols. The rate of accumulation of those compounds occurred before 30th WAFD. Some of these compounds (4-desmethylsterols and phytostanols) showed nearly the same profile during the ripening of Meski olive which could be linked to the relation between these compounds during their biosynthetic pathway.     

Provision of quality of service in wireless fourth generation networks

A key word describing next generation wireless networks is ‘seamless’. Wireless fourth generation (4G) networks represent a set of new technologies that will enable seamless integration of various wireless access systems, while targeting to support various sophisticated and quality of service constraining applications, such as high‐speed data services and multimedia services. This paper first proposes an architecture for 4G networks. The most significant feature of this architecture is its flexibility, openness and ability to enable seamless handoff in a single logical overlay network composed of many heterogeneous access networks. A medium access control (MAC) protocol for basic access networks is then introduced. A generic scheduling scheme, named CS‐EDF (channel state‐earliest deadline first) and the details of an efficient handoff management method are also briefly introduced. The bandwidth utilization, handoff resources reservation, and scheduling scheme performances of the proposed schemes are discussed. Copyright © 2006 John Wiley & Sons, Ltd.     

A new analytical solution to the mechanical behaviour of fully grouted rockbolts subjected to pull-out tests

A new analytical approach able to predict the mechanical behaviour of fully grouted rockbolts subjected to pull-out tests is proposed in this paper. Input parameters of such approach are: bolt radius, bolt’s Young modulus, displacement of the free end of the bolt and the constitutive law of the rockbolt–grout joint interface. The limited circumstances under which it is accurate to determine such constitutive law from pull-out tests are also presented. A solution for the load–displacement curve obtained during pull-out tests has been developed and is detailed in the case of a tri-linear bond-slip model. Comparison with experimental results obtained via in situ pull-out tests has led to the validation of this approach.     

Modeling of hybrid photovoltaic/wind/fuel cells power system

In this paper, identification and modeling of a hybrid photovoltaic/wind/fuel cells power system is presented. This system comprises also a battery storage supplying a load via an inverter. The identification of each subsystem has been made and then the proposed system is modeled and simulated under Matlab/Simulink Package. The power control of the hybrid system is introduced by using LabVIEW Software. The mathematical model topology and its power management of the global system with battery bank system are significant contributions of our work. The proposed control strategy has been experimentally implanted and practical results are compared to those obtained by simulation under the same metrological conditions, showing the effectiveness of the proposed hybrid system.