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Experimental and Numerical Analyses of the Pull-out Response of a Steel Post/Bovine Bone Cementless Fixation

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Journal of Bionic Engineering 2012年第4期9卷 501-507页

作者： Khaled gammoudi Mohamed Kharrat Maher Dammak National Engineering School of Sfax Electromechanical Systems Laboratory Soukra road km 3.5 B.P. 1173 3038 Sfax Tunisia Higher Institute of Technological Studies of Gafsa University campus Sidi Ahmed Zarrouk 2112 Gafsa Tunisia Faculty of Sciences of Gafsa University campus Sidi Ahmed Zarrouk 2112 Gafsa Tunisia Preparatory Institute for Engineering Studies of Sfax Menzel Chaker Road Km 0.5 B.P. 1172 3018 Sfax Timisia

Effect of initial interference fit on pull-out strength in cementless fixation between bovine tibia and smooth stainless steel post was investigated in this study. Compressive behavior of bovine spongious bone was studied using mechanical testing in order to evaluate the elastic-plastic properties in different regions of the proximal tibia. Friction tests were carried out in the aim to evaluate the friction behavior of the contact between bovine spongious bone and stainless steel. A cylindrical stainless steel post inserted in a pre-drilled bovine tibia with an initial interference fit was taken as an in vitro model to assess the contribution of post fixation to the initial stability of the Total Knee Arthroplasty （TKA） tibial component. Pull-out experiments were carried out for different initial interference fits. Finite Element Models （FEM） using local elastic-plastic properties of the bovine bone were developed for the analysis of the experimental ultimate pull-out force results. At the post/bone interface, Coulomb friction was considered in the FEM calculations with pressure-dependent friction coefficient. It was found that the FEM results of the ultimate force are in good agreement with the experimental results. The analysis of the FEM interfacial stresses indicates that the micro-slip initiation depends on the local bone properties.

关键词： total knee arthroplasty bovine bone/steel post fixation interference fit puU-out strength FEM

Implementation of photovoltaic water pumping system with MPPT controls

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Frontiers in Energy 2015年第2期9卷 187-198页

作者： Najet REBEI Ali HMIDET Rabiaa gammoudi Othman HASNAOUI Unit of Research (ERCO) National Institute of Applied Sciences ofTunisia North Urban Center University of Carthage 1080 Tunis CedexTunisia

To increase the output efficiency of a photo- voltaic （PV） system, it is important to apply an efficient maximum power point tracking （MPPT） technique. This paper describes the analysis, the design and the experi- mental implementation of the tracking methods for a stand- alone PV system, using two approaches. The first one is the constant voltage （CV） MPPT method based on the optimum voltage, which was deduced experimentally, and considered as a reference value to extract the optimum power. The second one is the increment conductance （Inc- Cond） MPPT method based on the calculation of the power derivative extracted by the installation. The output controller can adjust the duty ratio to the optimum value. This optimum duty ratio is the input of a DC/DC boost converter which feeds a set of Moto-pump via a DC/AC inverter. This paper presents the details of the two approaches implemented, based on the system perfor- mance characteristics. Contributions are made in several aspects of the system, including converter design, system simulation, controller programming, and experimental setup. The MPPT control algorithms implemented extract the maximum power point （MPP）, with satisfactory performance and without steady-state oscillation. MATLAB/Simulink and dSpace DSll04 are used to conduct studies and implement algorithms. The two proposed methods have been validated by implementing the performance of the PV pumping systems installed on the roof of the research laboratory in INSAT Tunisia. Experimental results verify the feasibility and the improved functionality of the system.

关键词： photovoltaic generator (PVG) maximum

Fuzz-TIME: an intelligent system for managing fuzzy temporal information

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International Journal of Intelligent Computing and Cybernetics 2017年第2期10卷 200-222页

作者： Aymen gammoudi Allel Hadjali Boutheina Ben Yaghlane Institut Superieur De Gestion De Tunis LARODECTunisTunisia Laboratoire d’Informatique et d’Automatique pour les Systèmes École nationale supérieure de mécanique et d’aérotechniqueChasseneuil-du-PoitouFrance IHECT University of CarthageTunisTunisia

Purpose-Time modeling is a crucial feature in many application ***,temporal information often is not crisp,but is subjective and *** purpose of this paper is to address the issue related to the modeling and handling of imperfection inherent to both temporal relations and ***/methodology/approach-On the one hand,fuzzy extensions of Allen temporal relations are investigated and,on the other hand,extended temporal relations to define the positions of two fuzzy time intervals are ***,a database system,called Fuzzy Temporal Information Management and Exploitation(Fuzz-TIME),is developed for the purpose of processing fuzzy temporal ***-To evaluate the proposal,the authors have implemented a Fuzz-TIME system and created a fuzzy historical database for the querying *** demonstrative scenarios from history domain are proposed and *** limitations/implications-The authors have conducted some experiments on archaeological data to show the effectiveness of the Fuzz-TIME ***,thorough experiments on large-scale databases are highly desirable to show the behavior of the tool with respect to the performance and time execution *** implications-The tool developed(Fuzz-TIME)can have many practical applications where time information has to be dealt *** particular,in several real-world applications like history,medicine,criminal and financial domains,where time is often perceived or expressed in an imprecise/fuzzy *** implications-The social implications of this work can be expected,more particularly,in two domains:in the museum to manage,exploit and analysis the piece of information related to archives and historic data;and in the hospitals/medical organizations to deal with time information inherent to data about patients and ***/value-This paper presents the design and characterization of a novel and intelligent database system to process and manage

关键词： Information retrieval Fuzzy set theory Fuzzy temporal relations Fuzzy time intervals Temporal databases

Threshold Effects in the Capital Account Liberalization and Foreign Direct Investment Relationship

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Chinese Business Review 2014年第9期13卷 562-577页

作者： gammoudi Mouna Cherif Mondher Universite de Reims Region Champagne-Ardenne France

This paper examines how capital account liberalization （CAL） affects foreign direct investment （FDI） inflows. Authors use a dynamic panel model encompassing 14 Middle East countries over the period from 1985 to 2009. The findings suggest that countries that are able to reap the benefits of the capital openness policy satisfy certain threshold conditions regarding the level of financial development and institutional quality. Thus to promote FDI, governments in this region should develop a set of policies that not only focus on financial openness, but also on the improvement of the financial system and legal institutions.

关键词： capital account liberalization (CAL) foreign direct investment (FDI) institutional quality system GMM estimator

Screening of antibacterial activity in marine green, red and brown macroalgae from the western coast of Libya

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Natural Science 2013年第1期5卷 7-14页

作者： Rabia Alghazeer Fauzi Whida Entesar Abduelrhman Fatiem gammoudi Salah Azwai Biology department Faculty of Education Azzawiya University Azzawiya Libya Botany Department Faculty of Sciences Tripoli University Tripoli Libya Chemistry Department Faculty of Sciences Tripoli University Tripoli Libya Microbiology and Parasitology Department Faculty of Veterinary Medicine Tripoli University Tripoli Libya

Marine macroalgae are considered as an excellent source of bioactive compounds which has a broad range of biological activities including antibacterial and antioxidant. Crude methanolic and water extracts of 19 marine algal species (6 Chlorophyta, 8 Phaeophyta and 5 Rhodophyta) collected from the western coast of Libya were evaluated for antibacterial activity against pathogenic bacteria (4 Gram-positive, 4 Gram-nega- tive). The extracts showed a significant antibacterial activity against Gram positive (Staphylococcus aureus, Bacillus subtilis, Bacillus spp., and Staphylococcus epidermidis) as well as Gram negative bacteria (Escherichia coli, Salmonella typhi, Klebsiella spp., and Pseudomonas aerugi- nosa). The algal aqueous and methanolic extracts displayed different degrees of antimicrobial activities against different bacteria, in some cases methanolic extracts showed higher antibacterial activity than aqueous extracts. Among tested algae, Brown algae namely Cystoseira crinite exhibited the highest antibacterial activity among tested algal species.

关键词： Macroalgae Phytochemicals Screening Antibacterial Activity

<i>In Vitro</i>Antibacterial Activity of Flavonoid Extracts of Two Selected Libyan Algae against Multi-Drug Resistant Bacteria Isolated from Food Products

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Journal of Biosciences and Medicines 2017年第1期5卷 26-48页

作者： Rabia Alghazeer Abdalla Elmansori Moammar Sidati Ftaim gammoudi Salah Azwai Hesham Naas Aboubaker Garbaj Ibrahim Eldaghayes Department of Chemistry Faculty of Sciences University of Tripoli Tripoli Libya Department of Botany Faculty of Sciences University of Tripoli Tripoli Libya Marin Biology Research Center Tajura-East of Tripoli Tripoli Libya Department of Microbiology and Parasitology Faculty of Veterinary Medicine University of Tripoli Tripoli Libya Department of Food Hygiene and Control Faculty of Veterinary Medicine University of Tripoli Tripoli Libya

This study aimed to evaluate the antibacterial activity of flavonoids extracted from two Libyan brown algae namely Cystoseira compressa and Padina pavonica using microwave-assisted extraction method against pathogenic bacteria isolated from meat, meat products, milk and dairy products (Staphylococcus aureus subsp. aureus (5 isolates), Bacillus cereus (3 isolates), Bacillus pumilus (1 isolate), Salmonella enterica subsp. enteric (4 isolates) and Enterohaemor-rhagic Escherichia coli O157 (EHEC O157) (4 isolates)). All of these isolates were muti-drug resistant with high MAR index. The results showed that C. compressa extract exhibited better and stronger antibacterial activities against the seventeen tested isolates with inhibition zones diameter ranged from 14 - 22 mm compared to P. pavonica extract which showed positive effect against 9 isolates with low inhibition zone ranged from 11 - 16.5 mm. Flavonoids extracted from C. compressa also displayed the best spectrum of bactericidal effect with a ratio MBC/MIC ≤ 4 obtained on all susceptible tested bacterial strains. Flavonoids and proanthocyanidins significantly contributed to the antibacterial properties. The mode of action of these active extracts is under investigation.

关键词： Brown Algae Flavonoids Multi-Drug Resistant Bacteria Antibacterial Activity

A Novel 3-D Nano-assembly Bacteria Based Biosensor for Enhanced Detection of Heavy Metal Pollutants

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Journal of Environmental Science and Engineering(A) 2012年第7期1卷 924-935页

作者： Mina Souiri Ibtissem gammoudi Laurence Mora Hafedh Ben Ouada Thierry Jouenne Nicole Jaffrezic-Renault Corinne Dejous Ali Othmane Anthony C. Duncan Biophysic Laboratory LIMA Faculty of Medicine of Monastir University of Monastir Monastir 5019 Tunisia Department of Bioengineering of Cardiovascular Polymers Galilee Institute Villetaneuse 93430 France Laboratory of the Interfaces of the Advanced Materials Faculty of Sciences of Monastir Monastir 5000 Tunisia Proteomic Platform Faculty of Sciences of Rouen Mont Saint A ignan Cedex 76821 France Analytical Sciences Laboratory Claude Bernard Lyon 1 University Villeurbanne Cedex 69622 France University of Bordeaux Talence 33405 France

Nowadays, at a time of growing concern for sustainable development and compliance with environmental standards and legislation, the detection of heavy metal contaminants in environmental matrices represents a difficult but important task. The current major limitation lies in the poor detection limits of the targeted pollutant＇s trace concentrations by the available conventional techniques. In order to elaborate a novel ＂living＂ self assembled electrochemical 3-D biosensor, the authors propose a new concept to overcome this shortcoming. The advantages of the properties of polyelectrolyte-functionalized NBs （nanobeads） are combined along with the use of non covalently strongly bound micro-organisms. The designed 3-D biosensor is all the more promising as it has showed a significantly improved sensitivity. In fact, the detection limits of the tested heavy metals （cadmium and mercury） were as low as 1.0 × 10^-12 mol.L-1 and six to seven orders of magnitude lower than those provided by conventional 2-D biosensors. Furthermore, it is potentially applicable to a wide range of bioreceptor-pollutant detection systems.

关键词： Biosensor nanobeads PEM heavy metals E. coli EIS (electrochemical impedance spectroscopy).