770 research outputs found
Determinants of Graduate Unemployment in Tunisia
According to the report of the Central Bank of Tunisia (2009), the unemployment rate had reached 13.3% in 2009. This rate had steadily increased from 12.5% in 2006. This is one of the major challenges of the Tunisian economy and many countries of the MENA region. Furthermore, with more than 500 000 job seekers, the unemployment rate in Tunisia remains one of the highest in the MENA region. A feature of unemployment in Tunisia is the unemployment of graduates. The unemployment rate for this category of young people has recently grown dramatically from 16.9% in 2006 to 21.9% in 2009. This rate is expected to rise in coming years despite all the arrangements made for young graduates to insert them into the labour market. To understand the determinants of this type of unemployment, the paper is based on the diagnosis of the situation through a synthesis of the key findings of surveys conducted in 2005 and 2007 on the promotion of graduates in 2004. This diagnosis was supported by an econometric model linking the unemployment indicator to the key indicators of qualification. The massification of the higher education and the lack of creation of adequate jobs are the main causes of the exponential rise of the unemployment rate for graduates. This situation has forced many students to continue their studies, thus paradoxically minimizing their chances of being recruited because of their over qualification. With the exception of a few specialties such as medicine, computing, telecommunications and architecture, where opportunities are available, especially abroad, other types of graduates meet more or less difficulty on the labour market. The solutions to overcome this crisis of unemployment are rather difficult, requiring enormous resources over several years. These solutions would affect several areas; such as the higher education, the vocational training, the investment and the regional integration.
Espaces méditerranéens, vers une convergence politique et économique ?
Do political and commercial links between EUROMED member states tend to increase during the last decade? Tools from ‘Social Network Analysis' allow focusing on actors' relational structures and highlight the persistence of a centre-periphery organization within the EUROMED.Les liens politiques et commerciaux entre pays membres de l'Union pour la Méditerranée tendent-ils à se renforcer au cours de la dernière décennie ? Utiliser des méthodes issues de l'analyse des réseaux sociaux permet de mettre l'accent sur les structures relationnelles des acteurs et révèle la persistance d'une organisation centre-périphérie au sein de l'EUROMED
Image annotation and retrieval based on multi-modal feature clustering and similarity propagation.
The performance of content-based image retrieval systems has proved to be inherently constrained by the used low level features, and cannot give satisfactory results when the user\u27s high level concepts cannot be expressed by low level features. In an attempt to bridge this semantic gap, recent approaches started integrating both low level-visual features and high-level textual keywords. Unfortunately, manual image annotation is a tedious process and may not be possible for large image databases. In this thesis we propose a system for image retrieval that has three mains components. The first component of our system consists of a novel possibilistic clustering and feature weighting algorithm based on robust modeling of the Generalized Dirichlet (GD) finite mixture. Robust estimation of the mixture model parameters is achieved by incorporating two complementary types of membership degrees. The first one is a posterior probability that indicates the degree to which a point fits the estimated distribution. The second membership represents the degree of typicality and is used to indentify and discard noise points. Robustness to noisy and irrelevant features is achieved by transforming the data to make the features independent and follow Beta distribution, and learning optimal relevance weight for each feature subset within each cluster. We extend our algorithm to find the optimal number of clusters in an unsupervised and efficient way by exploiting some properties of the possibilistic membership function. We also outline a semi-supervised version of the proposed algorithm. In the second component of our system consists of a novel approach to unsupervised image annotation. Our approach is based on: (i) the proposed semi-supervised possibilistic clustering; (ii) a greedy selection and joining algorithm (GSJ); (iii) Bayes rule; and (iv) a probabilistic model that is based on possibilistic memebership degrees to annotate an image. The third component of the proposed system consists of an image retrieval framework based on multi-modal similarity propagation. The proposed framework is designed to deal with two data modalities: low-level visual features and high-level textual keywords generated by our proposed image annotation algorithm. The multi-modal similarity propagation system exploits the mutual reinforcement of relational data and results in a nonlinear combination of the different modalities. Specifically, it is used to learn the semantic similarities between images by leveraging the relationships between features from the different modalities. The proposed image annotation and retrieval approaches are implemented and tested with a standard benchmark dataset. We show the effectiveness of our clustering algorithm to handle high dimensional and noisy data. We compare our proposed image annotation approach to three state-of-the-art methods and demonstrate the effectiveness of the proposed image retrieval system
Updated management of malignant biliary tract tumors: an illustrative review
The management of malignant biliary tumors (MBTs) is complex and requires a multidisciplinary approach. Guidelines and methods of staging for biliary tumors have recently been released by main international societies, altering the clinical and radiologic approach to this pathologic condition. The aim of the present review is to detail the updated role of imaging in preoperative staging and follow-up and to illustrate clinical/therapeutic pathways. In addition, future perspectives on imaging and targeted/embolization therapies are outlined
Experimental Performance Evaluation and Frame Aggregation Enhancement in IEEE 802.11n WLANs
The IEEE 802.11n standard promises to extend today’s most popular WLAN standard by significantly increasing reach, reliability, and throughput. Ratified on September 2009, this standard defines many new physical and medium access control (MAC) layer enhancements. These enhancements aim to provide a data transmission rate of up to 600 Mbps. Since June 2007, 802.11n products are available on the enterprise market based on the draft 2.0. In this paper we investigate the effect of most of the proposed 802.11n MAC and physical layer features on the adhoc networks performance. We have performed several experiments in real conditions. The experimental results demonstrated the effectiveness of 802.11n enhancement. We have also examined the interoperability and fairness of 802.11n. The frame aggregation mechanism of 802.11n MAC layer can improve the efficiency of channel utilization by reducing the protocol overheads. We focused on the effect of frame aggregation on the support of voice and video applications in wireless networks. We also propose a new frame aggregation scheduler that considers specific QoS requirements for multimedia applications. We dynamically adjust the aggregated frame size based on frame's access category defined in 802.11e standard
Ischiopubic and odontoid synchondrosis in a boy with progressive pseudorheumatoid chondrodysplasia
<p>Abstract</p> <p>Purpose</p> <p>To present the case of a 14-year-old boy with clinical and radiographic features of pseudorheumatoid chondrodyspalsia with additional, potentially serious, cervical malformations.</p> <p>Methods</p> <p>Detailed clinical and radiological examinations were undertaken with emphasis on the usefulness of 3D-CT scanning.</p> <p>Results</p> <p>There was synchondrosis between the odontoid and the body of the axis and the cephalad part of the odontoid was detached. Bilateral ischiopubic ossification defects and ischiopubic and odontoid synchondroses were additional abnormalities. 3D-CT scan showed an orthotopic type of os odontoideum associated with an occult axial fracture.</p> <p>Conclusion</p> <p>Children who are younger than seven years of age are predisposed to develop odontoid fracture. The latter occur because of the presence of physiological odontoid synchondrosis, but fractures can result from trivial injuries as well as from high-energy trauma. The persistence of an infantile odontoid, with a large pre-adulthood head in children with skeletal dysplasias, is a major risk factor for sudden death or significant morbidity. Comprehensive orthopaedic management must follow early identification of these malformations.</p
When the silent child speaks: identity and subversion in Anthony Browne’s voices in the park
By examining the subversive discourse of both children, Charles and Smudge, this paper will focus on the child’s identity in Anthony Browne’s postmodern picture book Voices in the Park. Drawing on the postmodern theory and mainly on Lyotard’s perception of childhood as a time of intense creativity and imagination, where the child is free to explore the world in a way that is not bound by the adult’s rationality and logic, this paper will analyse how Charles’s and Smudge’s discourses dare to go against the normative discourse of their parents. Smudge manages to change her father’s discourse, while Charles deconstructs his mother’s discourse by exposing its flaws and creating the possibility for resistance. By analysing the underlying tensions between the normative discourses of the parents and that of the children, which Lyotard calls the ‘other of all discourse’, this study offers some insights into the identity of the child Browne presents to his readers. This paper highlights the nature of the agency the children manage to construct through their encounters in the park. It will conclude that although children are an integral part of the parents’ normative power structure, they manage to become a disruptive force of change from within the system itself
Analyse des MIB en vue d'extraction d'information pour le placement des tâches
Stage d'école d'ingénieur de Tunis. Rapport de stage.Les MIB classiques de la gestion SNMP contiennent de nombreuses informations. Dans le cadre du placement l'utilisation des informations de type réseau sont intéressantes. Néanmoins, peu d'information réellement utiles existent dans les MIB standard, surtout pour la découverte automatique de la topologie physique du réseau
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