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Frontiers in Energy 2016年第2期10卷 155-163页

作者： Louar FATEH Ouari AHMED Omeiri AMAR Djellad ABDELHAK bouras lakhdar Department of Electrical Engineering University of Badji MokhtarAnnaba 23000 Algeria Department of Electrical Engineering University of 20 Aout 1955Skikda Skikda 21000 Algeria

The interest for the use of renewable energies has increased, because of the increasing concerns of the environmental problems. Among renewable energies, wind energy is now widely used. Wind turbines based on an asynchronous generator with a wound rotor present the inconvenience of requiring a system of tings and brooms and a multiplier, inferring significant costs of maintenance. To limit these inconveniences, certain manufacturers developed wind turbines based on synchronous machines with large number of pairs of poles coupled directly with the turbine, avoiding using the multiplier. If the generator is equipped with permanent magnets, the system of rings and brooms is eliminated. The control of the permanent magnet synchronous generator （PMSG） can be affected with the implementation of various techniques of control. This paper presented a new approach mainly based on the control strategy of power production system based on the PMSG. In fact, a mathematical model that simulates the Matlab chain was established with the introduction of control techniques, such as direct control of the torque （DTC） to control the load side converter （LSC）, the control of the speed of the turbine and the DC-bus voltage ensured by PI regulators. To show the performance of the correctors used, some simulation results of the system were presented and analyzed.

关键词： wind turbine permanent magnet synchronous

Kostmann’s Neutropenia: A Case Report

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Open Journal of Pediatrics 2024年第5期14卷 869-872页

作者： Khaoula Achir Ilham Tadmori Mounia lakhdar Idrissi Fatima Zahra Souilmi Mohamed Hbibi Moustapha Hida Pediatric Department of CHU Hassan II in Fez Fez Morocco

Kostmann syndrome, or severe congenital neutropenia, is a rare condition in children marked by a neutrophil count of less than 500/mm3. This congenital agranulocytosis, an autosomal recessive genetic disorder, is often first identified by a neonatal infectious syndrome. The deficiency in neutrophils increases susceptibility to bacterial and fungal infections. Prior to the availability of hematopoietic growth factors, the disease was associated with significant morbidity and early mortality. We present the case of a 17-month-old boy who was admitted to the pediatric emergency department at Hassan II University Hospital in Fes with skin abscesses.

关键词： Kostmann Syndrome Severe Congenital Neutropenia Skin Abscesses

Extra-Axial Anaplastic Pleomorphic Xanthoastrocytoma Mimicking Meningioma: A Case Report with Literature Review

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Open Journal of Modern Neurosurgery 2024年第3期14卷 203-211页

作者： Kaoutar Stitou Ilias Zahir Oualid Mohammed Hmamouche Marouane Hammoud Faycal lakhdar Mohammed Benzagmout Khalid Chakour Mohammed El Faiz Chaoui Department of Neurosurgery University Hospital of Fez Fez Morocco

Background: A number of meningeal neoplastic lesions may radiologically and clinically simulate meningioma, include hemangiopericytomas, solitary fibrous tumors, schwannomas, hematolymphoid lesions, metastases, and others very rarely, also may clinically mimic meningiomas. Case Description: We present the case of A 28-year-old male patient, with no notable medical history, who presented with worsening headaches for 3 months, imbalance, and visual deficits, An initial MRI revealed extra-axial lesion involving the right Parieto-occipital, The tumor was hypointense on T1-weighted MR images, hyperintense signals on T2-weightedMR images, and heterogeneously enhanced suggestive of a meningioma, total resection was achieved, and the histopathological analysis confirmed the diagnosis of an angioblastic meningioma. However, 15 months later, the patient presented with the same initial visual complaints. A subsequent MRI showed lesion recurrence, leading to a second surgical intervention. The histopathological analysis confirmed the diagnosis of an anaplastic xanthoastrocytoma. Conclusion: This represents an unusual location for an anaplastic pleomorphic xanthoastrocytoma, which should broaden the differential diagnosis of extra-axial lesions.

关键词： Anaplastic Features BRAF Extra-Axial High Mitotic Rate High Proliferation Index Meningeal Pleomorphic Xanthoastrocytoma

Primary Multiple Cerebral Hydatid Cyst in 8 Year-Old Girl: A Rare Cause of Childhood Seizure

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Open Journal of Modern Neurosurgery 2024年第2期14卷 149-157页

Background: Cystic echinococcosis is a zoonotic infection that occurs worldwide. Humans are infected through ingestion of parasite eggs in contaminated food, water or through direct contact with infected dogs, which are the definite host. Humans serve accidentally as intermediate host, and occurrences are common in children and young adults. Cystic echinococcosis is endemic in Mediterranean, South American, Middle Eastern, Central Asia, East Africa countries and Australia. Multiple cerebral hydatid cysts are very rare with only a few reports in the literature. Case Description: We present the case of an 8-year-old girl who presented with focal seizures, hemiparesis, headache, vomiting and bilateral optic atrophy. Diagnostic workup was performed, and magnetic resonance imaging revealed multiple intracranial cysts predominantly in the right frontal region with significant mass effect. A total of 11 intracranial cysts were removed surgically, and the child recovered uneventfully. Conclusion: Neurosurgeons should keep hydatidosis in the list of differentials when evaluating patients with cystic diseases of the brain. Although the removal of such cysts is challenging, outcomes are excellent when cysts are evacuated without rupture and patients show complete resolution of symptoms.

关键词： Hydatid Cysts Multiple Hydatic Cysts Childhood Seizures

Expo 2020 Dubai’s Impact on the United Arab Emirates’Brand:A Quantitative Analysis About American and European Media Companies

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Journalism and Mass Communication 2024年第1期14卷 11-22页

作者： lakhdar Chadli Canadian University Dubai DubaiUnited Arab Emirates

Countries implement corporate communication initiatives to improve their international relations,achieve different business objectives,and reinforce their *** branding activities are mainly based on international events:sport,culture,social *** paper evaluates the Expo 2020 Dubai’s impact on the United Arab Emirates’*** conducted a literature review about nation branding,and then we resorted to 15 indicators to analyze how the most important newspapers from some of the most influential countries(United States,Russia,France,and Germany)covered this event from a journalistic and corporate communication *** results proved that 82 articles were published about this topic,and the most common criteria respected were quoting organizers(n=61),using the Expo’s logo(n=45)and the image of a falcon(n=43).We concluded that most media companies focused on facts related to the Expo and did references to the country’s identity(values,flag,falcon),but most of them did not include links to the Dubai Expo’s and UAE public authorities’websites.

关键词： corporate communication brand reputation countries international event

On Abstract Third-Order Differential Equation and Its Applications

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Acta Mathematica Sinica,English Series 2023年第3期39卷 399-411页

作者： Belkacem CHAOUCHI lakhdar BENAISSA Marko KOSTIC Department of Mathematics Faculty of Science and TechnologyUniversity of Khemis MilianaKhemis MilianaAlgeria Department of Mathematics Faculty of ScienceUniversity of AlgiersAlgeria Faculty of Technical Sciences University of Novi SadTrg D.Obradovica 621125 Novi SadSerbia

In this paper,we consider an abstract third-order differential equation and deduce some results on the maximal regularity of its strict *** assume that the inhomogeneity appearing in the right-hand term of this equation belongs to some anistropic Holder *** illustrate our results by a BVP involving a 3D Laplacian posed in a cusp domain of R^(4).

关键词： Abstract third-order differential equation cusp domain strict solution

Modeling of a distillation column based on NARMAX and Hammerstein models

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International Journal of Modeling, Simulation, and Scientific Computing 2017年第3期8卷 227-240页

作者： lakhdar Aggoune Yahya Chetouani Automatic Laboratory of Setif Department of Electrical Engineering Setif 1 UniversityMaaboudaStreet of Bejaia 19000Setif Algeria Universite de Rouen IUTChemical Engineering Department Rue Lavoisier76130 Mont-Saint-AignanFrance IRSEEM ESIGELECTechnopole du MadrilletAvenue Galilee 76800 Saint-Etienne-du-RouvrayFrance

The modeling of distillation column process is a very challenging problem because of the complex dynamic *** paper investigates a Nonlinear Autoregressive Moving Average with eXogenous input(NARMAX)model,and a Hammerstein model to approximate the evolution of the overhead temperature in a separation *** model development and validation are studied through experiments carried out on a distillation plant of laboratory *** model order selection criteria such as Aikeke’s Information Criterion(AIC),Root Mean Square Error(RMSE)and Nash–Sutcliffe Efficiency(NSE)are used to evaluate the prediction performance of the process *** results illustrate that both models produce acceptable predictions but the NARMAX model outperforms the Hammerstein model.

关键词： Black-box modeling NARMAX model Hammerstein model complex systems

Recognition of Offline Handwritten Arabic Words Using a Few Structural Features

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Computers, Materials & Continua 2021年第3期66卷 2875-2889页

作者： Abderrahmane Saidi Abdelmouneim Moulay lakhdar Mohammed Beladgham Department of Electrical Engineering Laboratory:LTITTahri Mohammed UniversityBechar08000Algeria

Handwriting recognition is one of the most significant problems in pattern recognition,many studies have been proposed to improve this recognition of handwritten text for different ***,Fewer studies have been done for the Arabic language and the processing of its texts remains a particularly distinctive problem due to the variability of writing styles and the nature of Arabic scripts compared to other *** present paper suggests a feature extraction technique for offlineArabic handwriting recognition.A handwriting recognition system for Arabic words using a few important structural features and based on a Radial Basis Function(RBF)neural networks is *** methods of feature extraction are central to achieve high recognition *** proposed methodology relies on a feature extraction technique based on many structural characteristics extracted from the word skeleton(subwords,diacritics,loops,ascenders,and descenders).In order to reach our purpose,we built our own word database and the proposed system has been successfully tested on a handwriting database of Algerian city names(wilayas).Finally,a simple classifier based on the radial basis function neural network is presented to recognize certain words to verify the reliability of the proposed feature *** experiments on some images of the benchmark IFN/ENIT database show that the proposed system improves recognition and the results obtained are indicative of the efficiency of our technique.

关键词： Offline Arabic handwriting recognition preprocessing feature extraction structural features RBF neural network

Inhomogeneous barrier height effect on the current–voltage characteristics of an Au/n-InP Schottky diode

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Journal of Semiconductors 2015年第12期36卷 81-86页

作者： Kamal Zeghdar lakhdar Dehimi Achour Saadoune Nouredine Sengouga Laboratory of Metallic and Semi-conducting Materials (LMSM) Université de Biskra Faculty of Science Université de Batna

We report the current-voltage （I-V） characteristics of the Schottky diode （Au/n-InP） as a function of temperature. The SILVACO-TCAD numerical simulator is used to calculate the I-V characteristic in the tem- perature range of 280-400 K. This is to study the effect of temperature on the I-V curves and assess the main parameters that characterize the Schottky diode such as the ideality factor, the height of the barrier and the series resistance. The I-V characteristics are analyzed on the basis of standard thermionic emission （TE） theory and the inhomogeneous barrier heights （BHs） assuming a Gaussian distribution. It is shown that the ideality factor de- creases while the barrier height increases with increasing temperature, on the basis of TE theory. Furthermore, the homogeneous BH value of approximately 0.524 eV for the device has been obtained from the linear relationship between the temperature-dependent experimentally effective BHs and ideality factors. The modified Richardson plot, according to the inhomogeneity of the BHs, has a good linearity over the temperature range. The evaluated Richardson constant A^＊ was 10.32 A·cm^-2·K^-2, which is close to the theoretical value of 9.4 A·cm^-2·K^-2 for nInP. The temperature dependence of the I-V characteristics of the Au/n-InP Schottky diode have been successfully explained on the basis of the thermionic emission （TE） mechanism with a Gaussian distribution of the Schottky barrier heights （SBHs）. Simulated I-V characteristics are in good agreement with the measurements [Korucu D, Mammadov T S. J Optoelectronics Advanced Materials, 2012, 14：41 ]. The barrier height obtained using Gaussian Schottky barrier distribution is 0.52 eV, which is about half the band gap of InP.

关键词： simulation SDB Silvaco InP temperature I-V-T

Effect of gate engineering in submicron GaAs MESFET for microwave frequency applications

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Journal of Semiconductors 2016年第4期37卷 39-43页

作者： Nacereddine lakhdar Brahim Lakehal Department of Electronics University of El Oued LEA Department of Electronics University of Batna Department of Electronics University of Kasdi Merbah Ouargla

We present an approach of GaAs MESFET incorporating the gate engineering effect to improve immunity against the short channel effects in order to enhance the scaling capability and the device performance for microwave frequency applications. In this context, a physics-based model for I–V characteristics and various microwave characteristics such as transconductance, cut-off frequency and maximum frequency of oscillation of submicron triple material gate（TM） GaAs MESFET are developed. The reduced short channel effects have also been discussed in combined designs i.e. TM, DM and SM in order to show the impact of our approach on the GaAs MESFETs-based device design. The proposed analytical models have been verified by their good agreement with 2D numerical simulations. The models developed in this paper will be useful for submicron and microwave analysis for circuit design.

关键词： gate engineering GaAs MESFET cut-off frequency short channel effects(SCEs) work function modeling