IMEKO Event Proceedings Search

   

Page 154 of 977 Results 1531 - 1540 of 9762

Efstathios Adamopoulos, Fulvio Rinaudo
An Updated Comparison on Contemporary Approaches for Digitization of Heritage Objects

Continuous developments on sensors, data acquisition techniques, algorithms and computational systems have enabled automation, higher processing velocities and increased metric accuracy regarding the modeling of tangible heritage. For applications on heritage artefacts or architectural details, scanning and photogrammetric systems based on structure-frommotion (SfM) approach have prevailed, due to lower costs, fast acquisition and processing, re-producibility of workflows and ability to capture high-resolution texture. This study presents an updated comparison of contemporary digitization approaches to examine in extent required processing stages, compare costs and evaluate produced 3D results according to their metric properties, quality of texture and visual fidelity.

Siwar Jebril, Raoudha Khanfir Ben Jenana, Chérif Dridi
Green Synthesis and Characterization of Silver Nanoparticles using aqueous extracts of three Tunisian plant species, Basil, Eucalyptus and Geranium

Green synthesis of silver nanoparticles (AgNPs) has been produced by mixing silver nitrate solution with leaf aqueous extracts of three Tunisian plants namely Basil, Eucalypltus and Geranium as a reducing and stabilizing agent for AgNPs. After only 10 min of reaction, the light yellow color of the plant leaf extract was changed to brown due to the reduction of silver ions to AgNPs, under ambient conditions. The formation of biosynthesized AgNPs was monitored by UV-Visible spectroscopy which revealed an absorption peak at 400 nm. X- Ray Diffraction (XRD) was used to confirm the average particle size of AgNPs which were found to be 40, 50 and 30 nm using Basil, Eucalypltus and Geranium leaves aqueous extracts, respectively. Fourier transform infrared (FTIR) spectrum confirmed the possible interaction between silver nanoparticles and capping agents.

Sabrine Khriji, Meriam Ben Ammar, Ahmed Fakhfakh, Ines Kammoun, Olfa Kanoun
Energy Aware Fault Tolerant Re-clustering Algorithm for Wireless Sensor Networks

Since communication and data transmission present the most energy consuming task in Wireless Sensor Networks (WSNs), cluster-based routing protocols emerged as significant solutions for the energy conservation problem. In this paper, a fault tolerant based unequal clustering algorithm is proposed to extend the network lifetime of wireless sensor nodes. A threshold value is fixed to avoid the re-clustering process in some rounds leading to reduce the total number of data packets. The performance of the improved clustering algorithm is carried out with the network simulator NS3. A comparison between both unequal clustering with and without fault tolerant technique shows that avoid holding the selection of CHs in some rounds achieves better performance in terms of energy consumption and network lifetime.

Menyar Ben Jaballah, Najib Ben Messaoued, Chérif Dridi
Optimisation of the GCE electrode Architectures based on MWCNT and Silver nanoparticles for Electrochemical Sensing of BPA

A novel electrochemical sensor for bisphenol A (BPA) comprising a functionalized multiwalled carbon nanotube (MWCNT) and a low cost Silver nanoparticle (AgNP) modified glassy carbon electrode (GCE) has been developed. The MWCNT was functionalized with carboxylate groups by nitric acid and was characterized by FT-IR . The electrochemical characterization of the developed sensor was investigated by cyclic voltammetry. Modified electrode architectures with MWCNT and different amounts of deposited AgNP layers were tested. Under the best experimental conditions, the sensor exhibited a linear response to BPA from 70 nM to 6000 nM, with a limit of detection of 40 nM. Finally, real samples tests in drinking water were tested.

Marwa Gassab, Achref Chebil, Chérif Dridi
Electrochemical Characteristic of Interdigital Electrodes Supercapacitors for Embedded Electronics

Micro-supercapacitors (MSCs) are drawing more and more attention in the field of energy storage devices due to their distinct advantages such as their high power density, good electrochemical performances and long maintenance-free lifetime. In this work, a simulative approach (based on FEM (finite element method)) was employed to investigate the interplay of architecture between the geometric parameters for different electrodes number, length and width of an interdigitated structure. Cyclic voltammetry (CV) have been numerically calculated showing the maximum current response for optimized geometry parameters (length = 6500 µm, 16 electrodes width = 200 µm) of about 92 mA/cm². All the results demonstrate that this kind of micro-supercapacitor is a promote candidate that can be used in future autonomous systems.

Malak Talbi, Ammar Al-Hamry, Priscila Rios Teixeira, Leonardo G. Paterno, Mounir Ben Ali, Olfa Kanoun
Investigation of Nitrite Detection with Electrochemical Impedance Spectroscopy

An electrochemical impedance spectroscopy study is described for the determination of nitrite. A screen printed carbon electrode (SPCE) was modified with biocompatible gold nanoparticles stabilized by a polymer (branched polyethyleneimine). The modified SPCE exhibits high electro catalytic activity toward nitrite oxidation, typically at a working potential at around 0.5 V (vs. Ag/AgCl). Sensitive impedimetric detection of nitrite is demonstrated. The studied detection range extends from 1 to 10000 µM. Based on found results, the sensor’s performances will be calculated (limit of detection, sensitivity, linear range...) and further studies like stability and selectivity test will be continued.

Ghada Bouattour, Ayda Bouhamed, Ammar Al-Hamry, Rajarajan Ramalingame, Houda Ben Jmeaa Derbel, Olfa Kanoun
Design and Investigation on Flexible Inductive Power Tranmission Shields

Inductive power transmission coils are more and more used to charge devices wirelessly. In many applications, robustness, small size and flexibility of the used coils are required. For that, a design of flexible coil associated to a flexible ferrite shield becomes a necessity in order to achieve an efficient power transfer. In this paper, a new material composition for the ferrite shield have been proposed. It guarantees a better flexibility and performance using a simple fabrication process. Therefore, an optimization of the ferrite shield concentrations and thicknesses are performed. The influence of different prepared ferrite shield on the coil self-inductance and quality factor are investigated. Results shows that a concentration of ferrite of about 85 wt. % present the highest efficiency in case of high thickness with a self-inductance of 20.5 µH while in low concentration the measured coil self-inductance is around 17.5 µH.

E. Moke Aman, A. Lay-Ekuakille, S. Kidiamboko Guwa Gwa Band, J. Djungha Okadiowo
Metrics of Expression of Results in Environmental Noise Monitoring Processing: Machine Learning Approach

Although modern instruments for environmental noise are equipped with sophisticated devices, the accuracy and uncertainty for discriminating a source from another one, hence a group from another, depend upon the variability of the signal content. Conventional techniques exhibit limits for this kind of variability. The paper proposes an approach according to machine learning technique for processing different levels of environmental noise, classifying them.

Dhouha El Houssaini, Sabrine Khriji, Kamel Besbes, Olfa Kanoun
Real Time Temperature Measurement for Industrial Environment

Temperature measurement is critical for several ap- plications, where the detection of any environmental changes can be triggered by sever problem, such as fire, aeration irregularity and system fault. Considering, Wireless Sensor Networks (WSNs) in industrial monitoring applications presents as an alternative solution for real time and continuous measurement systems. They enable to have a complete overview of the monitored area and the state of the system itself as well. A real time measurement system based on WSNs is proposed to monitor the temperature in industrial environment. In this work, energy efficient, and cost effective sensor nodes were chosen for the WSNs in order to enable to extend the lifetime of the network and reduce the maintenance fees. For this reasons, the low power wireless platform panStamp NRG 2.0 is used. To measure the environmental temperature, two sensors were used; SI7021 and DHT11.

D. Mpoyi Katamba, A. Lay-Ekuakille, S. Kidiamboko Guwa Gwa Band
Application of Empirical Mode Decomposition for Tool Wear Monitoring using Vibration Measurement

Tool wear monitoring requires excellent capabilities of detecting small defects within the item under test. Diverse techniques have been using to detect the effect of vibrations on a tool, hence on material. The paper presents an EMD (empirical mode decomposition) approach for point out the effect of vibrations for a tool under machining in industrial process. EMD exhibits good results in processing some signals and simplicity in its use.

Page 154 of 977 Results 1531 - 1540 of 9762