4,192 research outputs found
Multiphase Modular Multilevel Converter Based Drive System for Oil and Gas Recovery in Subsea Applications
Get PDFAdjustable Speed Drives (ASDs) in subsea/offshore oil and gas applications are involved in several processes throughout production, transportation, and treatment phases, as they supply pumps and compressors. Therefore, ASDs’ in subsea applications have gone through continuous development. The currently existing systems exhibit several energy-conversion challenges that negatively impact the industry costs and green energy. In order to improve the energy-conversion efficiencies, this thesis, apparently, adopts a trend of using low-rating semiconductor devices to handle medium-/high-voltage levels along the various drive system stages. A trend that is believed, by the author, to become in the near future the foundation of flexible, redundant, and compact energy-conversion in the majority of medium-/high-voltage power applications. This thesis proposes the employment of Modular Multilevel Converters (MMCs) in MV-ASD applications in order to ease a transformerless operation while handling medium voltages using low-rating semiconductors. This, in return, reduces the system size and weight. The zero-/low-speed operation of MMC-based ASDs (a main challenge of applying MMCs in ASDs) is investigated in this thesis. The recent techniques proposed to improve operation during those intervals, implement complex hardware/software approaches. To cope with this issue, this thesis proposes multiphase machines for MMC-based AC-drives. Among several advantages regarding the power splitting, multiphase machines provide additional degrees of freedom compared to their three-phase counterparts. Novel exploitation to these additional degrees of freedom is proposed by injecting a secondary current component in the load current with specific magnitude and frequency during zero-/low-speed intervals enabling the drive system to function duly. Since the control of these secondary components is already inherited in the current controller structure of any multiphase machine, no additional algorithms or sensors will be required. Moreover, a hybrid-boost MMC converter is proposed to boost the MMC output voltage. The stepped output voltage generated by the MMC reduces or eliminates the filtering requirements. The boosting capability of the proposed architecture eliminates the need for bulky low-frequency transformers at the converter output terminals. In order to enhance the drive output torque, a Trapezoidal Phase Disposition Pulse Width Modulation Technique (TPD-PWM) is proposed in this thesis. Different slope angles of the trapezoidal modulation signal are tested and compared to other modulation techniques in order to select the angle with the best torque enhancement meanwhile maintaining good Total Harmonic Distortion (THD) levels. Moreover, the adopted modulation technique reduces the switching losses compared to the conventional Sinusoidal-based PWM. Eventually, a series-connected Half-Bridge (HB) modules are proposed as an Active Front End (AFE) rectifier for the drive system in order to generate an adequate DC-link voltage for the medium-voltage drive system using low-rating semiconductor devices. The proposed techniques through this thesis have been supported with both experimental and simulation results
Daoud, Mohamed (2014): المعجـم الموسوعى للتعبير الاصطلاحى فى اللغة العربية. (El diccionario enciclopédico de la expresión idiomática en la lengua árabe), Cairo, Dar Nahda, 1544 pp. [Reseña]
Get PDFReview of Daoud, Mohamed (2014): المعجـم الموسوعى للتعبير الاصطلاحى فى اللغة العربية. (El diccionario enciclopédico de la expresión idiomática en la lengua árabe), Cairo, Dar Nahda, 1544 pp. Reseña de Daoud, Mohamed (2014): المعجـم الموسوعى للتعبير الاصطلاحى فى اللغة العربية. (El diccionario enciclopédico de la expresión idiomática en la lengua árabe), Cairo, Dar Nahda, 1544 pp. Recensión de Daoud, Mohamed (2014): المعجـم الموسوعى للتعبير الاصطلاحى فى اللغة العربية. (El diccionario enciclopédico de la expresión idiomática en la lengua árabe), Cairo, Dar Nahda, 1544 pp. 
Phonation in Somali phonology
No full textThe author presents a phonological study on Somali language, in particular it focuses on the binary feature voiced/unvoiced stating its inadequacy.Qoraagu wuxuu halkan ku muujinayaa daraasaad ku saabsan codaynta Af-soomaaliga, wuxuuna si gaar ah diiradda u saarayaa labada qaab codlle/codlaawe oo aan is lahayn.L'autore presenta uno studio fonologico sulla lingua somala: in particolare definisce il tratto binario sonoro/sordo inadeguato ad un'esauriente descrizione della lingua.Mohamed Mohamed Abdi (a cura di
Hautverdächtig
Get PDFBook Title: Postcolonial Studies; Racial Profiling
Chapter Title: Hautverdächtig
Author(s): Mohamed Wa Baile, Ellen Höhne
Publisher: transcript Verlag
DOI: 10.14361/9783839441459-004
ISBN(s): 978-3-8376-4145-5, 978-3-8394-4145-9
ISSN(s): 2703-1233, 2703-124
The Nixon Doctrine and U.S. Relations with the Republic of Afghanistan, 1973–1978: Stuck in the Middle with Daoud
No full text The overthrow of the monarchy in Afghanistan in 1973 was a seminal moment in the country's history and in U.S. policy in Central Asia. The return of Mohamed Daoud Khan to power was aided by the People's Democratic Party of Afghanistan (PDPA, the Communist party) and military officers trained in the Soviet Union. Even as Communism was making its first substantive gains in Afghanistan, the United States was wrestling with how best to pursue its strategy of containment. Stung by the experience of Vietnam, President Richard Nixon concluded that the United States could not unilaterally respond to every instance of Communist expansion. In the turbulent years that followed, U.S. diplomacy and Daoud's desire for nonalignment combined to mitigate Soviet influence in Afghanistan. However, the U.S. triumph was fleeting insofar as Daoud's shift toward nonalignment triggered the erosion of Soviet-Afghan relations, culminating in the overthrow of his government and the final ascension of the PDPA. </jats:p
Entretien avec Mohamed Miloud Gharrafi
Get PDFMohamed Miloud Gharrafi, auteur de plusieurs recueils de poèmes en arabe, a signé, en 2014, une anthologie bilingue de ses poèmes autotraduits, augmentée d’inédits, intitulée Échos lointains. Il a accepté de s’entretenir avec nous sur sa pratique d’écrivain et de traducteur, et de présenter sa vision de l’acte de traduction et de ses relations avec la création, aussi bien dans le cas de l’autotraduction que dans celui de la traduction d’autres poètes, dont il a fait l’expérience à plusieurs reprises. Cette réflexion l’amène à poser la question des liens complexes, dans la poésie et sa traduction, entre la forme et le sens. Elle l’amène également à décrire son rapport, à la fois de filiation et de rupture, avec la tradition poétique arabe, ainsi que ses appartenances multiples à divers univers culturels et littéraires.Mohamed Miloud Gharrafi, author of several collections of poems in Arabic, signed a bilingual anthology of his self-translated poems in 2014, supplemented by unpublished ones, entitled Échos lointains. He has agreed to talk with us about his practice as a writer and translator, and to present his vision of the act of translation and its relationship with creation, both in the case of self-translation and in the case of the translation of other poets, which he has experienced on several occasions. This reflection leads him to question the complex links, in poetry and its translation, between form and meaning. It also leads him to describe his relationship, both of filiation and rupture, with the Arab poetic tradition, as well as his multiple affiliations to various cultural and literary worlds
Mohamed Enver Surty’s In Pursuit of Dignity
Get PDFIn Pursuit of Dignity is the unusual autobiography of our erstwhile Deputy Minister of Basic Education, Mohamed Enver Surty. The author served in government for twenty five years with distinction, and can be justly proud of a distinguished career both as a lawyer and as a government minister
Department of Modern Languages and Civilizations, Faculty of Humanities, University of Genoa, Italy
Get PDFThis research reviews the history of the Anglo-Iranian Oil Company in Iran since Darcy obtained the oil concession in 1903 and then the establishment of the Anglo-Iranian Oil Company, which controlled the extraction and sale of oil in Iran until 1950, the year that witnessed the rise of the national trend in Iran Led by Mohamed Mosadegh, he entered into a conflict with Britain after he nationalized the Anglo-Iranian Oil Company, which London saw as a dangerous development, which prompted it to present the issue to the Security Council. Oil nationalization, and with the failure of all political attempts to dissuade Mosadegh from his decision, both London and Washington resorted to supporting the Iranian opposition and the dismissal of the Iranian prime minister on August 19, 1953, and the approval of the new prime minister on the decision to cancel the nationalization of oil in 1954. Here the researcher followed the descriptive analytical method. He also relied on a number of US State Department documents and British documents in this study, as well as documents of the United Nations and the World Bank
Tradurre la bande dessinée migrante. Il caso de Les Mohamed di Jérôme Ruillier
Get PDFThe comic book Les Mohamed (2011) by French author Jérôme Ruillier is situated in the landscape of migrant bande dessinée, with its own singular characteristics. In this work, the author traced a global portrait of Maghrebi immigrants in France, by adapting the documentary/book Mémoires d’immigrés (1997) by French-Algerian author Yamina Benguigui. As migrant storytellers in general, bande dessinée authors are often the first ‘translators’ of unknown or removed realities, making them accessible to a large public. But what happen when they are translated in their turn? In a first part, this article canvases the process of intersemiotic translation that brought from Mémoires d’immigrés to Les Mohamed. In a second part, it focuses on the verbal/visual aspects of Ruillier’s work and especially on the solutions I adopted in the Italian translation (Se ti chiami Mohamed 2015)
Orality as Aesthetic Device: Articulating Language, Religion, and Authority in Mohamed Akounad’s Tawargit d Imik
Get PDFThis article explores Mohamed Akounad\u27s novel Tawargit d imik, which focuses on protagonist Ssi Brahim who struggles to convey the essence of his religious sermons to an exclusively amazigh audience amidst societal opposition. By examining Ssi Brahim\u27s character as the author\u27s alter ego, the study aims to assess the novel\u27s portrayal of religious concerns and activism for Tamazight and identity, particularly in relation to orality. Employing a sociolinguistic approach drawing from Bourdieu\u27s Language and Symbolic Power, the analysis delves into the intersection of religion, authority, and language, placing orality at the heart of their role within the narrative. This study proposes a dual analytical approach, comprising textual and transtextual analyses, in order to unravel the protagonist\u27s journey and explore intertextual connections with sacred texts.
Keywords: orality, intertextuality, language, linguistic capital, symbolic capital, Tamazight, religion, powe
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