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Search Results: 1 - 10 of 403 matches for " Asma Zidi "
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Invasive Thymoma with Endobronchial Polypoid Growth  [PDF]
Samira Aouadi, Emna Braham, Ayda Ayadi, Houda Gharsalli, Asma Zidi, Adel Marghli, Sonia Maalej, Leila Douik El Gharbi
Open Journal of Respiratory Diseases (OJRD) , 2015, DOI: 10.4236/ojrd.2015.54008
Abstract: Thymomas are the most common neoplasms of the mediastinum. It is common that thymoma invades neighboring structures in the thorax, but direct polypoid tumor growth into the airway is extremely rare. We report a rare case of invasive thymoma with polypoid endobronchial growth in a 66-year-old woman. Computed tomography demonstrated an anterior mediastinal tumor which extended into the right upper lobe. Endoscopic examination revealed a polypoid tumor which occluded the right upper bronchus. A biopsy specimen obtained from the intraluminal mass was very suggestive of thymoma. The patient had no parathymic syndrome. The tumor was resected with the right upper lobe. The final post-operative tissue findings confirmed a type B2 thymoma of the World Health Organisation classification.
A Generalized Framework for Ontology-Based Information Retrieval Application to a public-transportation system
Amir Zidi,Mourad Abed
Computer Science , 2014, DOI: 10.1109/ICAdLT.2013.6568453
Abstract: In this paper we present a generic framework for ontology-based information retrieval. We focus on the recognition of semantic information extracted from data sources and the mapping of this knowledge into ontology. In order to achieve more scalability, we propose an approach for semantic indexing based on entity retrieval model. In addition, we have used ontology of public transportation domain in order to validate these proposals. Finally, we evaluated our system using ontology mapping and real world data sources. Experiments show that our framework can provide meaningful search results.
Effects of Fiber Weight Ratio, Structure and Fiber Modification onto Flexural Properties of Luffa-Polyester Composites  [PDF]
Lassaad Ghali, Slah Msahli, Mondher Zidi, Faouzi Sakli
Advances in Materials Physics and Chemistry (AMPC) , 2011, DOI: 10.4236/ampc.2011.13013
Abstract: The effect of chemical modification, reinforcement structure and fiber weight ratio on the flexural proprieties of Luffa-polyester composites was studied. A unsaturated polyester matrix reinforced with a mat of Luffa external wall fibers (ComLEMat), a short Luffa external wall fibers(ComLEBC) and a short Luffa core fi-bers (ComLCBC) was fabricated under various conditions of fibers treatments (combined process, acetylat-ing and cyanoethylating) and fiber weight ratio. It resorts that acetylating and cyanoethylating enhance the flexural strength and the flexural modulus. The fiber weight ratio influenced the flexural properties of com-posites. Indeed, a maximum value of strength and strain is observed over a 10% fiber weight ratio. The uses of various reinforcement structures were investigated. The enhancement of elongation at break and the strain values of the composite reinforced by natural mat was proved.
A High Dynamic Range GMI Current Sensor  [PDF]
Aktham Asfour, Jean-Paul Yonnet, Manel Zidi
Journal of Sensor Technology (JST) , 2012, DOI: 10.4236/jst.2012.24023
Abstract: The design and performances of a high dynamic range DC-AC current sensor utilizing Giant Magneto-Impedance (GMI) are presented. The sensor is based on a GMI element with negative feedback. The sensing element is a 30 μm diameter GMI Co-based amorphous wire. It is curled to a toroidal core of 2 cm diameter. A bias magnetic field of about 650 A/m is applied to the GMI element to obtain an asymmetric GMI effect. A strong negative feedback is introduced to ensure linearity in a wide dynamic range. Analog conditioning electronics was fully developed. This includes a square wave oscillator based on an inverter trigger; a peak detector and a high gain amplifier with zero adjust. The GMI element is driven at a 3 MHz frequency and 5 mA peak-to-peak current. The closed-loop operations are investigated and the performances of the sensor are presented. DC current measurements are performed. The sensor exhibits good sensitivity and very good linearity, free from hysteresis, in a wide dynamic range of ±40 A. The sensitivity is about 0.24 V/A and the linearity error is about 0.02% of the full scale (FS). The hysteresis error is smaller than the measurement accuracy. AC current measurements using the developed sensor have also been successfully achieved. The sensor bandwidth in closed-loop was about 1.7 kHz.
Development of Large-Scale Land Information System (LIS) by Using Geographic Information System (GIS) and Field Surveying  [PDF]
Asma Th. Ibraheem
Engineering (ENG) , 2012, DOI: 10.4236/eng.2012.42014
Abstract: Cadastral maps are an important component of land administration in most countries. In virtually all developed countries, the needs of computerized land and geographic information systems (LIS/GIS) has given urgent impetus to computerizing cadastral maps and creating digital cadastral data bases (DCDB). This process is creating many institutional, legal, technical and administrative problems. This desire to establish DCDBs is being given increased impetus due to a new range of enabling technologies such as satellite position fixing (GPS), improved spatial data collection techniques such as digital theodolites and “soft copy” photogrammetry, as well as a vast range of new information and communications technological tools, thus contributing to the advancement and keeping up with the great countries. This paper presents the problem of cadastral maps. The hitherto existing cadastre, consisting of paper maps and land registers, is now becoming insufficient. Its shortcomings force developments leading to its improvement. One of the ways is the creation of a Land Information System. A digital cadastral map is the main component of this system. The structure and information content of the map is presented, its differences from analogue maps are shown, and the process of map creation is described. A digital cadastral map can be the basis for additional thematic layers, successively converting it into a complex system for management of administrative units.
Groundwater Over-Pumping and Recent Earthquakes in the Northern United Arab Emirates: A Natural Hazard Accentuated by Human Activity  [PDF]
Asma Al-Farraj
Journal of Water Resource and Protection (JWARP) , 2012, DOI: 10.4236/jwarp.2012.49092
Abstract: At the present day the United Arab Emirates (UAE) is on the flank of the Arabian plate, but some way away from the major modern earthquake epicentres. It normally experiences only minor earthquakes whose epicentres lie along the suture between the Arabian and Asiatic plates in Iran, the Arabian Gulf and the Gulf of Oman. In March 2002 a series of earthquakes occurred in several areas in the northern UAE, with foci along fault lines within the UAE. What made these earthquakes different from earlier earthquakes was their strength and frequency. For the first time in the area, earthquakes of a magnitude 5.5 (on the Richter scale) occurred, and continued over a period of three days. The causes appear to involve more than fault zone and plate tectonics, and may be related to human activity. Tracing the earthquakes during the past three decades indicates that the earthquakes followed major groundwater over-pumping, itself a result of population growth, growth in the number of farms and number of bottled water factories.
Estimation of Soil Erosion Risk Using the Universal Soil Loss Equation (USLE) and Geo-Information Technology in Oued El Makhazine Watershed, Morocco  [PDF]
Asma Belasri, Abdellah Lakhouili
Journal of Geographic Information System (JGIS) , 2016, DOI: 10.4236/jgis.2016.81010
Abstract: Soil erosion by water is one of the major threats to soils in the north of Morocco; soil erosion not only decreases agricultural productivity, but also reduces the water availability. In the current study, Oued El Makhazine watershed is selected to estimate annual soil loss using the Universal Soil Loss Equation (USLE), remote sensing (RS) and geographic information system (GIS). GIS data layers including, rainfall erosivity (R), soil erodibility (K), slope length and steepness (LS), cover management (C) and conservation practice (P) factors are computed to determine their effects on average annual soil loss in the area. The resultant map of annual soil erosion shows a maximum soil loss of 735 t·h-1·y-1, about 65.25% (1575 km2), of the watershed ranges between 0 and 95 t·h-1·y-1. Higher soil losses are observed at higher LS factor area. The spatial erosion maps generate with USLE method, remote sensing and GIS can serve as effective inputs in deriving strategies for land planning and management in the environmentally sensitive mountainous areas.
Trade Creation and Trade Diversion between Tunisia and EU: Analysis by Gravity Model
Ahmed Zidi,Said Miloud Dhifallah
International Journal of Economics and Finance , 2013, DOI: 10.5539/ijef.v5n5p131
Abstract: Since the middle of nineties, there has been a great rise of free trade agreements (FTAs) between the North and South countries. Indeed, the objective of this article is to know if FTASbetween an ndustrialized region as Europe and a small country as Tunisia are capable of increasing exchanges among them and then improving the trade of the weakest country. Our aim is to know if agreements between industrial countries and developed countries are able to increase trade between them and therefore improve the trade of the less developed country. To answer to this question we evaluate the two effects of regional integration: trade creation and diversion trade. We obtain two main results: the first result is after five years of the agreement between Tunisia and Europe, there is no trade creation. The second result shows that the preferential agreement between the two partners does not generate trade diversion of imports. However, there is a trade diversion of exports.
An Extensive Cholesteatoma with Bezold’s Abscess  [PDF]
Norhafiza Mat Lazim, Asma Abdullah
International Journal of Clinical Medicine (IJCM) , 2011, DOI: 10.4236/ijcm.2011.23049
Abstract: Cholesteatoma has been known to be associated with multiple complications either extracranially or intracranially. Among the extracranial complications, mastoiditis and mastoid abscess are the most common. Bezold’s abscess formation with cholesteatoma is a rare occurrence but when present can lead to sinister sequalae if not properly managed. The treatment of cholesteatoma is mainly by surgical exploration namely mastoidectomy. The aim of treatment is to eradicate the diseased mastoid and to prevent subsequent complications. Beside surgical intervention, the patient will also require intensive systemic and topical antibiotic therapy. With proper treatment patient will be hindered from experiencing unwanted complications.
Bayesian Estimation of Non-Gaussian Stochastic Volatility Models  [PDF]
Asma Graja Elabed, Afif Masmoudi
Journal of Mathematical Finance (JMF) , 2014, DOI: 10.4236/jmf.2014.42009
Abstract:

In this paper, a general Non-Gaussian Stochastic Volatility model is proposed instead of the usual Gaussian model largely studied. We consider a new specification of SV model where the innovations of the return process have centered non-Gaussian error distribution rather than the standard Gaussian distribution usually employed. The model describes the behaviour of random time fluctuations in stock prices observed in the financial markets. It offers a response to better model the heavy tails and the abrupt changes observed in financial time series. We consider the Laplace density as a special case of non-Gaussian SV models to be applied to our data base. Markov Chain Monte Carlo technique, based on the bayesian analysis, has been employed to estimate the model’s parameters.

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