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Impact Assessment of Technology Change on Durum Wheat Productivity： A Cross Sectional Analysis in Central Semi-arid Tunisia

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Journal of Agricultural Science and Technology(B) 2014年第1期4卷 49-57页

作者： ali Chebil aymen Frija Sondes Amri National Institute for Research in Rural Engineering Waters and Forests (1NRGREF) Ariana 2080 Tunisia Higher School of Agriculture (ESA) Mograne Zaghouan 1121 Tunisia

The enhancement of wheat yield in Tunisia becomes a must for policy makers who need to reduce the importations of this commodity. In this context, the ＂Food Security in Arab Countries＂ project has been established in order to transfer technological innovations that improve irrigated wheat productivity. As a pilot area, this project is being implemented in Chebika （Central Tunisia） region, where in the last two years a new technological package of durum wheat production has been tested by many farmers of the region. The objective of this study is to identify the sources of output gains between farmers participating in the project trials and farmer＇s using conventional techniques. Tornqvist-Thiel index was used for the identification of the output gains generated by the technology package. Data used for the analysis were collected from 60 participating farmers during 2011-2012 cropping season, and 110 non-participating farmers. Results show that average production value differential between participating and non-participating farmers is 48.4%. This value is composed of 9.3% gain generated from global factor productivity and 39.1% from the increase of the inputs use. It also indicates the relative importance of inputs contributing to the global factor productivity difference between enhanced technological package and conventional practices in the region. These results are valuable for policy makers since they can be used to focus on main factors affecting the improvement of irrigated wheat productivity in Central Tunisia. Encouraging the adoption of the new technological package is then highly recommended.

关键词： Technological package irrigated wheat Tornqvist-Thiel index productivity gains Central Tunisia.

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The Double Excitation： A Solution to Improve Energetic Performances of High Power Synchronous Machines

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Journal of Energy and Power Engineering 2012年第5期6卷 719-724页

作者： aymen Ammar Frederic Gillon Pascal Brochet Laboratory of Electrical Engineering and Power Electronics Ecole Centrale de Lille University of Lille North of France Villeneuved'Ascq 59650 France

DFSM （doubly fed synchronous machine） presents several advantages such as efficiency improvement, weight reduction and increase of the utilization factor （kW/kg）. In this paper the authors focus on impact of the DFSM on the efficiency and machine weight in comparison to conventional synchronous generator with wound rotor. Different topologies of DFSM are briefly described and the different methods and models for performances prediction are presented.

关键词： Double excitation losses no load characteristic permanent magnet reluctances network vector diagram.

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The Breeding Status of the Glossy Ibis Plegadis falcinellus in the Lebna Dam in Cap Bon, Tunisia

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Journal of Life Sciences 2012年第7期6卷 776-782页

作者： aymen Nefla Ridha Ouni Sad Nouira Department of Biology University of Sciences of Tunis El Manar 11 Tunis 2092 Tunisia Association for the Protection of Environmental and Natural Heritage Bejaoua 2 SidiThabet CP. 2020 Tunisia

The study of the reproduction of the Glossy Ibis （Plegadisfalcinellus） in Tunisia was undertaken from 2008 to 2010. Until the discovery of nesting in 2008, this species had only been considered as wintering in Tunisia. The Tunisian breeding population resides in the Lebna Dam in the north east of the country where it forms a mixed nesting colony with other species of the family Ardeidae （（Bubulcus ibis （Bi）： 388 pairs, Ardeola ralloides （Ar）： 17 pairs, Egretta garzetta （Eg）： 27 pairs）, （Bi： 300 pairs, At： 25 pairs, Eg： 40 pairs） and （Bi： 400 pairs, Ar： 30 pairs, Eg： 10 pairs） recorded in 2008, 2009 and 2010 respectively）. all nests were constructed on Acacia horrida. Laying began in early May. The average clutch size over the three years of the study was 3.44 ± 0.73 eggs （N = 29 nests）. Hatching success was 83 % （2.86 ± 1.18 eggs hatched/nest） and 2.65 ± 1.17 hatchlings/nest survived until the age of 10 to 12 days. Egg mortality was 17% during the incubation phase and chick mortality was 7.2%. No interannual variation was detected in these parameters.

关键词： Breeding parameters Plegadisfalcinellus Lebna dam Tunisia.

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Reperfusion of Delayed Acute Occlusive Limb Ischemia: Is It Worthwhile?

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World Journal of Cardiovascular Diseases 2014年第12期4卷 580-585页

作者： Mohamed A. Elsharawy aymen Elsaid Ibrahim Elsharawi Vascular Division Department of Surgery University of Dammam Al-Khobar KSA Royal College of Surgeon of Ireland Busaiteen Bahrein

Delayed reperfusion of acute occlusive limb ischemia causes local and systemic serious consequences and is the main cause of morbidity and mortality in these patients. The aim of this study was to examine the outcome and risk factors of reperfusion injury in such cases. Patients and Methods: Retrospective review of all cases presented, to King Fahd Hospital of University, with acute occlusive limb ischemia more than 12 hours was performed between June 2004 and November 2012. Grades of ischemia, extremities, comorbidities, morbidities and mortality were recorded. Results: During the study period, 92 patients were included, 47 (51%) were embolic and the rest was thrombotic. On admission, 15 patients had grade III ischemia, 68 had grade IIb, 8 had grade IIa and 1 had grade I. Four patients died (4.3%) and 15 (16%) patients had amputation. The risk factors of amputation were age (p = 0.031), extremity (lower limb 21% vs. Upper limb 0%, p = 0.019), cause of ischemia (thrombotic 24% vs. embolic 8.5%, p = 0.049) and grade of ischemia (p = 0.001). Conclusion: Delayed reperfusion of acute occlusive ischemia carries acceptable morbidity and mortality and could be performed even in irreversible ischemia. The risk factors of amputation are age, lower limb ischemia, thrombosis and grade III ischemia.

关键词： Acute Limb Ischemia Thrombosis Embolism Delayed Ischemia

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Comparison the Performances of Three Earthing Systems for Micro-Grid Protection during the Grid Connected Mode

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Smart Grid and Renewable Energy 2011年第3期2卷 206-215页

作者： Rashad Mohammedeen Kamel aymen Chaouachi Ken Nagasaka 不详

This paper presents, tests and compares three earthing systems (TT, TN and IT) for Micro-Grid (MG) protection against various fault types during the connected mode. The main contribution of this work is including the models of all the micro sources which interfaced to the MG by power electronic inverters. Inverters in turns are provided with current limiters and this also included in the inverter models to exactly simulate the real situation in the MG during fault times. Results proved that the most suitable earthing system for MG protection during the connecting mode is the TN earthing system. That system leads to a suitable amount of fault current sufficient to activate over current protection relays. With using TN system, Touch voltages at the faulted bus and all other consumer’s buses are less than the safety limited value if current limiter is included with the transformer of the main grid which connects MG. For the two others earthing systems (TT and IT), fault current is small and nearly equal to the over load current which make over current protection relay can not differentiate between fault current and overload current. all models of micro sources, earthing systems, inverters, main grid and control schemes are built using Matlab?/Simulink? environment.

关键词： Micro Grid Protection Earthing Systems Fault Current Touch Voltage Micro Sources and Inverters Grid Connecting Mode

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Enhancing Hygrothermal Performance in Multi-Zone Constructions through Phase Change Material Integration

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Frontiers in Heat and Mass Transfer 2024年第3期22卷 769-789页

作者： Abir Abboud Zakaria Triki Rachid Djeffal Sidi Mohammed El Amine Bekkouche Hichem Tahraoui Abdeltif Amrane aymen Amin Assadi Lotfi Khozami Jie Zhang Laboratory of Biomaterials and Transport Phenomena University of MedeaMedea26000Algeria Unitéde Recherche Appliquée en Energies Renouvelables(URAER)Centre de Développement des Energies Renouvelables(CDER) Ghardaia47133Algeria Laboratoire de Génie des Procédés Chimiques Department of Process EngineeringUniversity of Ferhat AbbasSetif19000Algeria Universitéde Rennes Ecole Nationale Supérieure de Chimie de RennesCNRSISCR-UMR6226Rennes35000France College of Engineering Imam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia School of Engineering Merz CourtNewcastle UniversityNewcastle upon TyneNE17RUUK

As buildings evolve to meet the challenges of energy efficiency and indoor comfort,phase change materials(PCM)emerge as a promising solution due to their ability to store and release latent *** paper explores the transformative impact of incorporating PCMon the hygrothermal dynamics of multi-zone *** study focuses on analyzing heat transfer,particularly through thermal conduction,in a wall containing PCM.A novel approach was proposed,wherein the studied system(sensitive balance)interacts directly with a latent balance to realistically define the behavior of specific humidity and mass flow *** addition,a numerical model implemented in MATLAB software has been developed to investigate the effect of integrating PCM on the hygrothermal balances inside the *** obtained results indicate a consistent response in internal temperatures,specific humidity,and mass flow rates,with temperature differences ranging from 5℃to 13℃and a maximum phase shift of 13 *** addition,the findings provided valuable insights into optimizing the design and performance of multi-zone constructions,offering a sustainable pathway for enhancing building resilience and occupant well-being.

关键词： Multi-zone constructions phase changematerial hygrothermal balances heat transfer thermal conduction energy efficiency

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Design and Testing of Three Earthing Systems for Micro-Grid Protection during the Islanding Mode

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Smart Grid and Renewable Energy 2010年第3期1卷 132-142页

作者： Rashad M. Kamel aymen Chaouachi Ken Nagasaka 不详

This paper presents and tests three earthing systems (TT, TN and IT) for Micro-Grid (MG) protection against various fault types when the MG transferred to the islanding mode. The main contribution of this work is including the models of all micro sources which interfaced to the MG by power electronic inverters. Inverters in turns are provided with current limiters and this also included with the inverter models to exactly simulate the real situation in the MG during fault times. Results proved that the most suitable earthing system for MG protection during the islanding mode is the TN earthing system. That system leads to a suitable amount of fault current sufficient to activate over current pro-tection relays. With using TN earthing system, touch voltages at the faulted bus and all other consumer’s buses are less than the safety limited values during islanding mode. For the two others earthing systems (TT and IT), fault currents are small and nearly equal to the over load currents which make over current protection relay can not differentiate between fault currents and overload currents. all models of micro sources, earthing systems, inverters and control schemes are built using Matlab?/Simulink? environment.

关键词： Micro Grid Protection Earthing Systems Fault Current Touch Voltage Micro Sources and Inverters

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Hidden Markov Models for Automatic Speech Recognition

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Journal of Mechanics Engineering and Automation 2011年第1期1卷 68-73页

作者： Mbarki aymen Ammari Abdelaziz Sghaier Halim Hassen Maaref Laboratory of Micro-Optoelectronique and Nanostructure Faculty of Sciences Monastir 5000 Tunisia

In this paper the authors look into the problem of Hidden Markov Models （HMM）： the evaluation, the decoding and the learning problem. The authors have explored an approach to increase the effectiveness of HMM in the speech recognition field. although hidden Markov modeling has significantly improved the performance of current speech-recognition systems, the general problem of completely fluent speaker-independent speech recognition is still far from being solved. For example, there is no system which is capable of reliably recognizing unconstrained conversational speech. also, there does not exist a good way to infer the language structure from a limited corpus of spoken sentences statistically. Therefore, the authors want to provide an overview of the theory of HMM, discuss the role of statistical methods, and point out a range of theoretical and practical issues that deserve attention and are necessary to understand so as to further advance research in the field of speech recognition.

关键词： Hidden markov models (HMMs) speech recognition HMM problems viterbi algorithm.

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Experimental Study of Osmotic Dehydration of Date （Phoenix dactylifera L,）： Application for Lemsi Cultivars

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Journal of Food Science and Engineering 2013年第7期3卷 388-393页

作者： Sdayria aymen Farhat Abdelhamid Bellagha Sihem Sahli ali Laboratoire d 'Energ~tique et des Transferts Thermiques et Massique LETTM FST Universit~ de Tunis AI-Manar Tunisie Laboratoire de Maitrise des Technologies de l 'Energie LMTE Centre de Recherche et des Technologies de l 'Energie CRTEn BP95 Hammam Lif 2050 Tunisie lnstitut National Agronomique de Tunis Tunis 1082 Tunisie

The cultivar date Lemsi is well known in the coastal oasis of Tunisia for both its quality stage ＂blah＂ and its earliness. This variety is characterized by its astringent taste and has never been studied extensively. An osmotic dehydration treatment is necessary to improve the quality of the final product for maintaining its integrity. Thus, it is a preservation technique that is often used as pretreatment to obtain partially dehydrated fruit. In this experimental study, the cultivar date Lemsi were cut into cubes of 1 cm3 and were immersed in sucrose solutions of 50%, 60% and 70% at 20℃ for 0-240 min. The moisture content, the solute gain, the water loss and the ratio WL/SG are determined and discussed. The results deduced from this work have showed that sugar gain SG, water loss WL and the ratio WL/SG are increased with concentration of osmotic solution. Likewise, the osmotic dehydration treatment need to be followed of a convective drying to ensure the quality of the final product.

关键词： Osmotic dehydration Phoenix dactilifera L. lemsi cultivars water loss solute gain.

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Diagnostic Accuracy of IS6110 Insertion Gene, <i>Hsp65</i>, and Xpert MTB/RIF for Rapid Diagnosis of Pulmonary Tuberculosis

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Journal of Tuberculosis Research 2017年第1期5卷 1-12页

作者： aymen Awad Abdelhaleem almonther Abdallah Hershan Pradeep Kumar Agarwal Endemic and Tropical Diseases Unit Medical Research Center Jazan University Jazan Saudi Arabia Faculty of Medical Laboratory Sciences Alneelain University Khartoum Sudan Faculty of Medicine Jazan University Jazan Saudi Arabia Jazan Chest Disorders Hospital Jazan Saudi Arabia

Purpose: To evaluate diagnostic accuracy of IS6110 insertion genes, hsp65, and Xpert MTB/RIF for rapid diagnosis of pulmonary tuberculosis. Methods: Sixty patients, medically reported HIV negative, clinically suspected of having pulmonary tuberculosis, were included in this study, and consented before enrolment. Sputum samples were gathered once, and tested by smear for Acid Fast Bacilli (AFB). Cultured in the Loewenstein-Jensen (LJ) medium for M. tuberculosis growth, M. tuberculosis DNA was detected by conventional PCR targeting IS6110, and hsp65 genes using specific primers, and automated nested real-time PCR targeting rpoB gene. Sensitivity, specificity and diagnostic accuracy were calculated for each method compared to culture. Results: Compared with culture as reference method, smear, IS6110, hsp65, and Xpert MTB/RIF had sensitivity 77.14%, 100%, 100%, and 100%, specificity 92%, 96%, 96%, and 96.97%, and diagnostic accuracy 83.33%, 98.33%, 98.33% and 98.21% respectively. Molecular diagnostic methods had the highest diagnostic accuracy, whereas smear had the lowest. No statistical significance, (p value > 0.05) was detected between the patients’ demographic data and the presence or absence of TB infection. Conclusion: The diagnostic accuracy that we got from the molecular methods, confirmed the diagnostic value of molecular detection of M. tuberculosis in pulmonary cases, supporting the application of automated and conventional PCR in rapid analysis. Smear could be more efficient when used for treatment monitoring. Combination between one-molecular techniques with smear as a routine method could be valid for rapid diagnosis of TB.

关键词： Rapid Diagnosis Pulmonary TB Molecular Tests

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