Tunisian National Institute of Applied Sciences and Technology

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Tunisian National Institute of Applied Sciences and Technology

Tunisia
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Clodoveo M.L.,University of Bari | Hachicha Hbaieb R.,Tunisian National Institute of Applied Sciences and Technology
Food Research International | Year: 2013

The entire virgin olive oil (VOO) process has changed very little over the last 20years. One of the essential challenges of VOO industrial plant manufacturing is to design and build advanced machines in order to improve the working capacity of the industrial plants and create more sustainable engineering solutions. Ultrasound (US) and microwave (MW) are emerging technologies that have already found application in the food industry. Yet, application in the VOO sector has been scarcely investigated. In order to ascertain if the mentioned emerging technologies are able to increase the environmental sustainability improving VOO extraction yields, two different treatments (US and MW) of olive paste were adopted in the VOO extraction process on a pilot scale plant. In these experimental conditions, the main parameters legally established (acidity, peroxide value, and specific extinction coefficients (K232 and K270)) to evaluate VOO quality were not affected by the US and MW treatments. Moreover US and MW processes reduced significantly the length of the malaxation and improved the extraction yield as compared with the control when the oils were extracted from the paste without malaxation. Results also prove that US technology was more sustainable than MW which appears as an energy consuming method in a pilot scale plant. Therefore the industrial application of these technologies could represent the first step toward the development of continuous new devices. © 2013 Elsevier Ltd.


Haouas H.,Tunisian National Institute of Applied Sciences and Technology
Hematology | Year: 2014

Background: Angiogenesis is a word of Greek origin, 'angeio' refers to blood vessel, and genesis refers to creation, meaning the generation of new blood vessels. This process is essential for vertebratedevelopment and plays a key role in human diseases. Angiogenesis is generally understood to be essential for the growth and metastasis of solid tumors and is also important in acute myeloid leukemia (AML). Methods: This review summarizes the essential features of physiological and tumoral angiogenesis and the methods used for their assessment. Results: Technologies for evaluating angiogenesis in AML are discussed and the prognostic significance of angiogenic factors is considered in the context of optimizing treatment. Conclusion: As acute myelogenous leukemia and endothelial cells depend on each other for survival and proliferation, therapy directed against several pro-angiogenic factors might help to enhance the AML outcome. © W. S. Maney & Son Ltd 2014.


Boubaker O.,Tunisian National Institute of Applied Sciences and Technology
International Journal of Advanced Robotic Systems | Year: 2013

For at least fifty years, the inverted pendulum has been the most popular benchmark, among others, in nonlinear control theory. The fundamental focus of this work is to enhance the wealth of this robotic benchmark and provide an overall picture of historical and current trend developments in nonlinear control theory, based on its simple structure and its rich nonlinear model. In this review, we will try to explain the high popularity of such a robotic benchmark, which is frequently used to realize experimental models, validate the efficiency of emerging control techniques and verify their implementation. We also attempt to provide details on how many standard techniques in control theory fail when tested on such a benchmark. More than 100 references in the open literature, dating back to 1960, are compiled to provide a survey of emerging ideas and challenging problems in nonlinear control theory accomplished and verified using this robotic system. Possible future trends that we can envision based on the review of this area are also presented. © 2013 Boubaker.


Mehdi H.,Tunisian National Institute of Applied Sciences and Technology | Boubaker O.,Tunisian National Institute of Applied Sciences and Technology
International Journal of Advanced Robotic Systems | Year: 2011

This paper presents an efficient and fast method for fine tuning the controller parameters of robot manipulators in constrained motion. The stability of the robotic system is proved using a Lyapunov-based impedance approach whereas the optimal design of the controller parameters are tuned, in offline, by a Particle Swarm Optimization (PSO) algorithm. For designing the PSO method, different index performances are considered in both joint and Cartesian spaces. A 3DOF manipulator constrained to a circular trajectory is finally used to validate the performances of the proposed approach. The simulation results show the stability and the performances of the proposed approach. © 2011 Mehdi and Boubaker; licensee InTech.


Messaoud C.,Tunisian National Institute of Applied Sciences and Technology | Boussaid M.,Tunisian National Institute of Applied Sciences and Technology
Chemistry and Biodiversity | Year: 2011

Extracts of mature dark blue and white berries from two Tunisian Myrtus communis morphs growing at the same site were assessed for their essential-oil and fatty-acid compositions, phenolic contents, and antioxidant activities. The GC and GC/MS analyses of the essential oils allowed the identification of 33 constituents. The oils from the dark blue fruits showed high percentages of α-pinene (11.1%), linalool (11.6%), α-terpineol (15.7%), methyl eugenol (6.2%), and geraniol (3.7%). Myrtenyl acetate (20.3%) was found to be the major compound in the oils from white berries. GC Analysis of the pericarp and seed fatty acids showed that the polyunsaturated fatty acids constituted the major fraction (54.3-78.1%). The highest percentages of linoleic acid (78.0%) and oleic acid (20.0%) were observed in the seeds and the pericarps of the white fruits, respectively. The total phenol, flavonoid, and flavonol contents and the concentration of the eight anthocyanins, identified by HPLC analysis, were significantly higher in the dark blue fruits. All extracts showed a substantial antioxidant activity, assessed by the free radical-scavenging activity and the ferric reducing power, with the dark blue fruit extracts being more effective. © 2011 Verlag Helvetica Chimica Acta AG, Zürich.


Mehdi H.,Tunisian National Institute of Applied Sciences and Technology | Boubaker O.,Tunisian National Institute of Applied Sciences and Technology
International Journal of Social Robotics | Year: 2012

In this paper, stiffness and impedance control concepts are used to solve position and force control for robot-aided rehabilitation. New asymptotic stability conditions are proposed using a suitable Lyapunov approach and based on the relationship between the dynamics of the robot and its energy. The efficiency of the proposed approach is tested on a planar 3 DOF robot-aided rehabilitation constrained to a circular trajectory. The robotic device is configured to be safe and stable in compliant motion in contact with the human arm. It is also designed to be adapted easily to different subjects for performing different tasks. Force and control parameters are tuned using a non linear optimization strategy for which the stability conditions are considered as inequality constraints. Simulation results show that the robot could guide the upper limb of subjects in circular movements under predefined model of the external force and prove the stability and the performances of the compliant motion control strategy. © 2011 Springer Science & Business Media BV.


Aloulou A.,Tunisian National Institute of Applied Sciences and Technology | Boubaker O.,Tunisian National Institute of Applied Sciences and Technology
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2011

In this paper, an optimized gait pattern generation is produced for a three dimensional bipedal robot using a Minimum Jerk criterion in the single support phase. Three approaches are introduced and compared in this framework. The Minimum Jerk based control approaches are the point-to-point, the Via-point and the shape function trajectory. Simulation results show that the point-to-point Minimum Jerk-based control cannot be satisfactory since the supposed swinging leg of the bipedal robot doesńt lift off the ground. However, a bipedal stable human-like movement is guaranteed using both last approaches. © 2011 Springer-Verlag.


AbdelMalek F.,Tunisian National Institute of Applied Sciences and Technology
IEEE Photonics Technology Letters | Year: 2011

In this letter, we theoretically propose a biosensor based on a two-dimensional left-handed photonic crystal coupled to an M-shaped resonator. The sensor is optimized to operate in an aqueous environment. By controlling the radius of the air cylinder defect, a strong interaction between light and biomolecules in aqueous solution is achieved. We demonstrate numerically that by confining the biomolecular into the region of interest, a high sensitivity is reached. It is shown that shifts in the peak wavelength values are strongly related to the refractive index changes. © 2006 IEEE.


Yosr Z.,Tunisian National Institute of Applied Sciences and Technology | Hnia C.,Tunisian National Institute of Applied Sciences and Technology | Rim T.,Tunisian National Institute of Applied Sciences and Technology | Mohamed B.,Tunisian National Institute of Applied Sciences and Technology
Industrial Crops and Products | Year: 2013

Rosmarinus officinalis var. typicus Batt. essential oils and acetonic extracts were isolated from different organs at different growth stages of branches developed after decapitation of the main stem apices of clonal plants. Oils assessed by GC-MS were present in high concentration (1.23 and 1.43%) in leaves being collected during the vegetative and flowering stages. Significant variations of component contents were observed according rather to organs than to phenological stages of branches. 1.8-Cineole (35.8%) was the main constituent in leaves, while, β-caryophyllene (16.7%) was identified as the main constituent for stems. Flowers were characterized by high levels of caryophyllene oxide (11.9%). The discrepancy could be due, either to differential oil accumulation or physiological and biochemical interactions within and among organs during morphogenesis.Total polyphenols (4.8-37.4%), flavonoids (3.0-28.5%) and condensed tannins (0.2-2.4%) were identified in all plant parts. The total polyphenols and condensed tannins were more accumulated in leaves (28.6 and 24.0. mg EAG/g DW) and their concentration was high at the vegetative and fruiting stages, suggesting that flowering contribute to the modification of their accumulation. The amounts of flavonoids in leaves and stems (14.7-17.5. mg ER/g DW) did not vary significantly in course of time. The level of antioxidant activity of acetonic extracts estimated by DPPH and FRAP test systems was high for leaf and stem extracts isolated at the flowering stage. Compared to the acetonic extracts, essential oils exhibited lower antioxidant activity. © 2012 Elsevier B.V.


Zaouali Y.,Tunisian National Institute of Applied Sciences and Technology | Bouzaine T.,Tunisian National Institute of Applied Sciences and Technology | Boussaid M.,Tunisian National Institute of Applied Sciences and Technology
Food and Chemical Toxicology | Year: 2010

The essential oil composition of Rosmarinus officinalis var. typicus and var. troglodytorum endemic to Tunisia, and growing wild in different bioclimates, was determined by GC and GC-MS. Oils were assessed for their antimicrobial and antioxidant activity. A variation of the chemical composition attributed to varieties rather than to bioclimates was revealed. 1.8-Cineole (47.2-27.5%) and camphor (12.9-27.9%) were identified as the main constituents of var. typicus and var. troglodytorum, respectively. The principal component analysis performed on oil constituents for all the populations allowed the distinction of two distinct population groups in accordance to the varietal subdivision. Based on the determination of the diameter of inhibition and the determination of the minimum inhibitory concentration, a low to moderate antimicrobial activity according to oils was revealed against eight bacteria tested. However, oils from var. troglodytorum showed higher bactericidal effect than those from var. typicus. The oils' antioxidant activity, determined by 1,1-diphenyl-1-picrylhydrazyl (DPPH) assay, ferric reducing (FRAP) assay and β-carotene bleaching test, was relatively high. The highest activity was found in oils from var. troglodytorum and in one population of var. typicus from the upper semi-arid bioclimate. © 2010.

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