498 research outputs found

    Automatic treebank-based acquisition of Arabic LFG dependency structures

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    A number of papers have reported on methods for the automatic acquisition of large-scale, probabilistic LFG-based grammatical resources from treebanks for English (Cahill and al., 2002), (Cahill and al., 2004), German (Cahill and al., 2003), Chinese (Burke, 2004), (Guo and al., 2007), Spanish (O’Donovan, 2004), (Chrupala and van Genabith, 2006) and French (Schluter and van Genabith, 2008). Here, we extend the LFG grammar acquisition approach to Arabic and the Penn Arabic Treebank (ATB) (Maamouri and Bies, 2004), adapting and extending the methodology of (Cahill and al., 2004) originally developed for English. Arabic is challenging because of its morphological richness and syntactic complexity. Currently 98% of ATB trees (without FRAG and X) produce a covering and connected f-structure. We conduct a qualitative evaluation of our annotation against a gold standard and achieve an f-score of 95%

    Parsing Arabic using treebank-based LFG resources

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    In this paper we present initial results on parsing Arabic using treebank-based parsers and automatic LFG f-structure annotation methodologies. The Arabic Annotation Algorithm (A3) (Tounsi et al., 2009) exploits the rich functional annotations in the Penn Arabic Treebank (ATB) (Bies and Maamouri, 2003; Maamouri and Bies, 2004) to assign LFG f-structure equations to trees. For parsing, we modify Bikel’s (2004) parser to learn ATB functional tags and merge phrasal categories with functional tags in the training data. Functional tags in parser output trees are then "unmasked" and available to A3 to assign f-structure equations. We evaluate the resulting f-structures against the DCU250 Arabic gold standard dependency bank (Al-Raheb et al., 2006). Currently we achieve a dependency f-score of 77%

    An automatically built named entity lexicon for Arabic

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    We have successfully adapted and extended the automatic Multilingual, Interoperable Named Entity Lexicon approach to Arabic, using Arabic WordNet (AWN) and Arabic Wikipedia (AWK). First, we extract AWN’s instantiable nouns and identify the corresponding categories and hyponym subcategories in AWK. Then, we exploit Wikipedia inter-lingual links to locate correspondences between articles in ten different languages in order to identify Named Entities (NEs). We apply keyword search on AWK abstracts to provide for Arabic articles that do not have a correspondence in any of the other languages. In addition, we perform a post-processing step to fetch further NEs from AWK not reachable through AWN. Finally, we investigate diacritization using matching with geonames databases, MADA-TOKAN tools and different heuristics for restoring vowel marks of Arabic NEs. Using this methodology, we have extracted approximately 45,000 Arabic NEs and built, to the best of our knowledge, the largest, most mature and well-structured Arabic NE lexical resource to date. We have stored and organised this lexicon following the Lexical Markup Framework (LMF) ISO standard. We conduct a quantitative and qualitative evaluation of the lexicon against a manually annotated gold standard and achieve precision scores from 95.83% (with 66.13% recall) to 99.31% (with 61.45% recall) according to different values of a threshold

    COMPATABILITY BETWEEN ARCHITECTURAL EDUCATION AND PROFESSIONAL PRACTICEIN EGYPT

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    The impact of education on countries urbanism is clear as much as culture, economy, and politics are. In Egypt, although urban education is usually appended by architectural education; the current educational methods, and content in architecture schools do not grant the needed convergence between educational institutions and the needs of professional practice regulations. This paper focuses on curricula of architectural education for under graduate engineering programs in Egypt. It analyzes various programs of architecture in higher education referring to the practice regulations. As well as investigating if they are reflected clearly on the architecture education or not. Case studies will include four main Egyptian undergraduate architectural engineering programs. The study uses the qualitative approach in which descriptive analysis of different disciplines ratios, and study hours taught to students during undergraduate phase is done. As the qualitative approach in the exposure to the rules and regulations presenting Egyptian professional practice. Two comparisons are held during the discussion, one between different educational programs systems in Egypt, and another one about fulfilling the role of architect authorized by law, and regulations. Finally, the research ends with a number of conclusions concerning the analytical study, and recommendations on connecting three main pillars, including the architecture education, the laws and regulations, and the professional practice requirements

    Handling unknown words in statistical latent-variable parsing models for Arabic, English and French

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    This paper presents a study of the impact of using simple and complex morphological clues to improve the classification of rare and unknown words for parsing. We compare this approach to a language-independent technique often used in parsers which is based solely on word frequencies. This study is applied to three languages that exhibit different levels of morphological expressiveness: Arabic, French and English. We integrate information about Arabic affixes and morphotactics into a PCFG-LA parser and obtain stateof-the-art accuracy. We also show that these morphological clues can be learnt automatically from an annotated corpus

    The Challenges and Risks facing ICT in the Management and Operation of the Smart Grid

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    The Smart Grid integrates the traditional electrical power grid with information and communication technologies (ICT). Such integration empowers the electrical utilities providers and consumers, improves the efficiency and the availability of the power system while constantly monitoring, controlling and managing the demands of customers. Through smart grid, the power system becomes smart by communicating, sensing, control and applying intelligence.The Smart Grid is also kept the environment free from pollution; minimize the cost, effective operations, against all types of hazards and danger.Smart Grid is a huge complex network composed of millions of devices and entities connected with each other through wireless communications techniques including Home Area Networks (HANs) and Wide Area Networks (WANs). Such a massive network comes with many security concerns and vulnerabilities. In this paper, we highlight the complexity of the smart grid network and discuss the comparison between heterogeneous network. We discuss then the challenges that exist in securing the smart power grid and the countermeasures and solutions applied for information and communication networks to secure Smart Power Grid. We conclude by over viewing the key functions and benefits of using the Smart Gird technology and how this impacts on human livelihood, economy and the environment.</p
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