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Wind energy is in the spotlight, it is nowadays the fastest growing source of energy in the world. The objective of this work is to examine wind power potential of Laayoune site using wind speed, wind direction, and other meteorological data collected during one year. This type of complete examination provides information of wind characteristics of potential sites and helps in choosing appropriate wind turbine. In the first part, we have been present a comparison of three methods for estimating parameters of Weibull distribution function wind speed data namely Standard Deviation , Least Squares and Mabchour’s. The comparison has been done using Excel sheet and ALWIN software. In second part, we have been compare three various wind turbines: WES 18-100KW, XANT M-21 100KW and Northem Power NPS 21- 100K for the production of a 50MW electric power from wind energy farm installed in Laayoune city. The criteria of turbine choice is based on the price per kilowatt hour and the higher annual production. The simulation results using HOMER and ALWIN software showed that the wind turbine: XANT M-21 100KW has the higher annual production with low cost of installation.

The research work presented in this study focuses on the construction and the analysis of a Maximum Power Point Tracking (MPPT) control system for a Wind Energy Conversion System (WECS) based on a Permanent Magnet Synchronous Generator (PMSG). The PMSG is a commonly used generator for direct-drive and variable-speed wind energy conversion. The study focuses on controlling the generator and the converter on the DC load side to follow the wind speed reference set by the MPPT algorithm. The paper presents the formulation of the optimisation problem, including the optimisation space, the restrictions, and the goals. The design improvement incorporates the use of Ant Colony Optimisation (ACO) to extract the maximum power of the WECS. In this study, both Proportional Integral Derivative (PID) controllers and the ACO heuristic approach are employed for controlling and stabilising the MPP of the power generated by the Wind Turbine (WT). The ACO approach is utilized to determine the optimal settings (Kp, Ki, Kd) based on five performance indicators: Integrated Squared Error (ISE), Integrated Absolute Error (IAE), Integrated Time Absolute Error (ITAE), Integrated Time Squared Error (ITSE), and the Mean Squared Error (MSE). The suggested system is modelled and simulated in Matlab/Simulink by using a 12.3 kW PMSG. The results show generated power, DC bus voltage, electromagnetic torque, and currents. The results of the simulation demonstrate that the WT can successfully track the necessary MPP. [ABSTRACT FROM AUTHOR]

Background: Abdominal desmoid tumors arise in young adults between 20 and 40 years. They are characterized by a local recurrence in 20 to 30% of cases., Aim: review the clinical and pathologic features of this entity, look for the expression of immunohistochemical markers (actine, desmine, CD34, vimentin) and also to estimate the expression of two potential targets therapy; the hormonal receptors and the CD117., Methods: From 1990 to 2004, three cases of abdominal desmoid tumors were diagnosed in the Pathologic laboratory of the Charles Nicole Hospital of Tunis., Results: The study concerned three women 62, 35 and 30 year-old. All the patients were operated and the size of tumours varied to 5 to 7cm. The CD117 and the hormonal receptors were negative in every case. None of the patients presented local recurrence., Conclusion: Abdominal desmoid tumors are locally aggressive but never give metastasis. The negativity of these lesions to the CD117 and in the hormonal receptors does not imply resistance in the hormonal treatment by anti-estrogens.

Background: Extra-adrenal pheochromocytoma is a rare entity. Its occurrence in the urinary bladder has only been reported less than 200 times., Aim: Report 2 news cases, Cases Report: Here we present two case reports of bladder paraganlioma with an update of the diagnostic techniques, treatment modalities and follow-up of patients with this disease. The common presentation of paraganglioma of the urinary bladder is painless haematuria, headache, palpitation and anxiety. Treatment of this lesion requires the same preparation as for any other site of pheochromocytoma. Partial cystectomy ensures radical and effective treatment. Long-term surveillance is necessary as recurrences or metastases have been described 20 and 40 years after treatment.

Primary hepatic carcinoid tumors are extremely rare, and fewer than 60 cases have been reported in the literature. Long-term follow-up is necessary for establishing the primary nature of liver carcinoids. We report a case arising in a young 20 years-man having Zollinger-Ellison syndrome on presentation. Intensive and careful investigation revealed no other origin of the tumor. Resection is the treatment of choice for primary hopatic carcinoid tumors. Their prognosis seems to be more favorable when compared with other hepatic carcinomas.

To establish the pathologic profile of broncho-pulmonary carcinoma, 869 cases were retrospectively collected. Mean age was 60, 1 years (range 13 - 98 years), with men predominating (10, 3 male (M) / 1 female (F). This sex-ratio was less than one recorded in 1994 (11, 5 M / 1F), and then the question is: did the womanly broncho-pulmonary carcinoma on the increase, in Tunisia?. 16, 5 % of women and 3, 9% of men were aged less than 41 years, but sex ratio was 2,4M / 1F. They represented 5, 1% of all cases. Such result differs from reports in the literature (1 - 3, 4%). In histological data, we noted that adenocarcinoma is actually more frequent than epidermoid carcinoma. Its ratio increased from 15, 3 % in 1994 to 30, 3 % in 2003, whereas, epidermoid carcinoma's ratio decreased from 42, 8 % to 29, 5 %. The relationship tobacco- different histological type of broncho-pulmonary carcinoma was clearly observed, varying between 90, 6% (adenocarcinoma) and 100 % (large cell carcinoma).