250 research outputs found

    Intéractions aérosols-rayonnement-nuages et variabilité climatique en méditerranée - Approche par la modelisation régionale couplée

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    Le bassin méditerranéen est sujet à de nombreuses sources d'aérosols présentant une variabilité spatio-temporelle élevée. Ces aérosols interagissent de manière directe avec les rayonnements solaire et thermique, et de manière indirecte avec les nuages et la dynamique atmosphérique. Ils peuvent donc avoir un impact important sur le climat de cette région. Ce travail de thèse, à la frontière entre les projets HyMeX et ChArMEx, considère une approche par la modélisation régionale couplée pour répondre aux questions des interactions aérosols-rayonnement-nuages par rapport à la variabilité climatique de la région méditerranéenne. Afin de mieux caractériser les aérosols méditerranéens, une nouvelle climatologie mensuelle et interannuelle d'épaisseur optique a été développée à partir d'une combinaison de produits satellites et de modèles. Ce jeu de données, disponible pour tous les modèles régionaux de climat en Méditerranée sur la période 1979-2012, a été mis au point dans le but d'obtenir la meilleure estimation possible du contenu atmosphérique en aérosols pour les cinq types considérés (sulfates, carbone suie et organique, poussières désertiques et sels marins). Des ensembles de simulations réalisées sur la période 2003-2009 avec et sans aérosols montrent un impact majeur sur le climat régional. Cet impact se caractérise par un forçage radiatif négatif en surface (dû à la diffusion et l'absorption du rayonnement solaire incident) de -15 W.m−2 en moyenne annuelle sur la mer Méditerranée, par un refroidissement induit en surface à la fois sur mer et sur terre de l'ordre de 0.5◦C en moyenne annuelle, par une diminution moyenne des précipitations ainsi que par des changements de nébulosité. Le cycle saisonnier et les structures spatiales du climat méditerranéen sont ainsi significativement modifiés, ainsi que certaines situations spécifiques comme la canicule de juillet 2006 qui a été renforcée par la présence d'aérosols désertiques. Le rôle essentiel de la température de surface de la mer Méditerranée dans la réponse du climat aux aérosols est mis en évidence, et permet de comprendre les modifications induites des flux air-mer (notamment la diminution de la perte en chaleur latente) et ses conséquences sur le climat régional. La convection océanique en mer Méditerranée est également renforcée par la présence d'aérosols. En outre, on démontre que la diminution des aérosols anthropiques observée depuis plus de trente ans a contribué significativement aux tendances climatiques de rayonnement (représentant 81 ± 15 % de l'éclaircissement) et de température (représentant 23 ± 5 % du réchauffement) observées en Europe et en Méditerranée. D'autre part, un schéma interactif d'aérosols a été mis en place dans le modèle atmosphérique ALADIN-Climat afin de pouvoir comprendre les processus liés aux aérosols à l'échelle quotidienne. On montre ici la capacité de ce schéma de simuler de manière réaliste les aérosols présents en Méditerranée, notamment dans le cas des intrusions de poussières désertiques observées pendant la campagne de mesures ChArMEx/TRAQA. Un exercice d'intercomparaison avec d'autres modèles intégrant les aérosols désertiques confirme la performance du nouveau schéma. De plus, utiliser un schéma prognostique d'aérosols au lieu d'une climatologie mensuelle permet de mieux reproduire les variations quotidiennes et en particulier les extrêmes de rayonnement et de température en surface. Cela induit aussi une modification du climat moyen, dans la mesure où les variations des aérosols et de leurs effets dépendent des régimes de temps et de la nébulosité. Cette thèse conclut ainsi à la nécessité pour les systèmes climatiques de modélisation régionale en Méditerranée de bien prendre en compte les effets radiatifs des aérosols et leur variabilité spatiotemporelle, y compris à haute fréquence. Les impacts de ces effets radiatifs sur de nombreux paramètres (rayonnement, température, humidité, flux air-mer, circulation océanique, etc.) sont en effet démontrés à différentes échelles d'espace et de temps (variabilité quotidienne, cycle saisonnier, tendances climatiques, extrêmes, structures spatiales). Ce travail a aussi montré que le couplage entre l'atmosphère et la mer Méditerranée est indispensable pour des études aérosols-climat dans cette région. ABSTRACT : The Mediterranean basin is affected by numerous and various aerosols which have a high spatiotemporal variability. These aerosols directly interact with solar and thermal radiation, and indirectly with clouds and atmospheric dynamics. Therefore they can have an important impact on the regional climate. This work, located at the boundary between the ChArMEx and HyMeX programs, considers a coupled regional modeling approach in order to address the questions of the aerosol-radiation-cloud interactions with regards to the climate variability over the Mediterranean. In order to improve the characterization of Mediterranean aerosols, a new interannual monthly climatology of aerosol optical depth has been developed from a blended product based on both satellitederived and model-simulated datasets. This dataset, available for every regional climate model over the Mediterranean for the 1979-2012 period, has been built to obtain the best possible estimate of the atmospheric aerosol content for the five species at stake (sulfate, black carbon, organic matter, desert dust and sea salt particles). Simulation ensembles, which have been carried out over the 2003-2009 period with and without aerosols, show a major impact on the regional climate. This impact is characterized by a negative surface radiative forcing (due to the absorption and the scattering of the solar incident radiation) of -15 W.m−2 on annual average over the Mediterranean Sea, an induced surface cooling both over land and sea of about -0.5◦C on annual average, a decrease in precipitation as well as cloud cover changes. The seasonal cycle and the spatial patterns of the Mediterranean climate are significantly modified, as well as some specific situations such as the heat wave in July 2006 strengthened by the presence of desert dust particles. The essential role of the Mediterranean sea surface temperature is highlighted, and enables to understand the induced changes on air-sea fluxes (notably the decrease in the latent heat loss) and the consequences on regional climate. Oceanic convection is also strengthened by aerosols. In addition, the decrease in anthropogenic aerosols observed for more than thirty years is shown to significantly contribute to the observed Euro-Mediterranean climatic trends in terms of surface radiation (representing 81 ± 15 % of the brightening) and temperature (representing 23 ± 5 % of the warming). Besides, an interactive aerosol scheme has been developed in the atmospheric model ALADINClimate in order to better understand aerosol processes at the daily scale. This scheme shows its ability to represent correctly the aerosol patterns over the Mediterranean, especially with regards to dust outbreaks that were measured during the ChArMEx/TRAQA field campaign. An intercomparison exercise with several dust models confirms the performance of the new scheme. Moreover, the use of a prognostic aerosol scheme instead of a monthly climatology enables to better reproduce the daily variations of surface radiation and temperature and related extremes. This also leads to changes in the mean climate, insofar as aerosol variations and their effects depend on weather regimes and cloud cover. Finally this study concludes with the need for regional climate system models over the Mediterranean to take into account the radiative aerosol effects and their spatio-temporal variability, including at high frequency. The impacts of these radiative effects on numerous parameters (radiation, temperature, humidity, ocean-atmosphere fluxes, oceanic circulation, etc.) are indeed shown and understood at different space and time scales (daily variability, seasonal cycle, climate trends, spatial structures). This work has also shown the importance of the coupling between the atmosphere and the Mediterranean Sea for aerosol-climate studies in this region

    Segmenting video frame images using genetic algorithms

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    Image segmentation plays an important role in computer vision. It is a process that partitions a digital image into several meaningful regions ,by identifying regions of an image that have common properties while separating regions that are dissimilar. The image segmentation problem is posed as an optimization procedure. In this thesis, an optimization approach based on genetic algorithm is introduced for finding optimal image segmentation. The design and implementation of genetic algorithm image segment or (GSAI) system are described. GSAI system employs finds optimal value using genetic operators "crossover operator and mutation operator". The different proposed / implementation segmentation methods of the GSAI system were tested using Gray image are taken from one films and with size 352x240 pixels for video frames images of In this is work focused on genetic algorithm coefficients which affect in direct and active way in the work of GA to study and analysis dependable video images which are taken from video clips after partitioning to multiple frames

    Partially Purification M Protein from Streptococcus Pyogens and Molecular Study of Some Virulence Factors

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    The current study was conducted to isolation one type of surface protein of Streptococcus pyogens this protein separated using partially purification method. Purifiction  process include precipitation of crude  M protein  one peak of this protein was appeared, the best precipitate rate was 30% . PCR assay were performed to identify the presence of some genes related to pathogenicity in bacteria responsible from Tonsillitis .Streptococcus pyogens represented the largest causative agent of inflammation of the tonsil so the study revealed the presence of certain gene in some isolate of bacteria, including the gene SpeB that gave large proportions in the study isolates 12 out of 37 at a rate of (32.4%). Keywords : S.pyogens , Tonsillitis , M protein ,PCR ,Spe

    Improved technique for hiding data in a colored and a monochrome image

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    Find a new way to hide the different types of confidential and important text files inside the images without noticing any change or distortion of the information in the images after the process of concealment or attempt to be detected by hackers. And then extract these texts and retrieved on demand without loss or loss or distortion of any of its content. The algorithm was used to hide the different text in different image formats using (256) elements, monochrome and color where about 4500 characters were hidden in a monochrome image and about 900 characters in a color image and with a hiding distance (S) where N = 3, key = 3. The overall error rate is low (0.05-0.17) and no distortions were observed on the resulting imag

    Pola dakwah Kyai dalam membangun Sosio-Religius masyarakat di Kecamatan Leces Kabupaten Probolinggo

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    ABSTRAK Kegiatan dakwah dalam Islam menjadi poros utama perkembangan agama Islam yang selalu menjadi sorotan para ulama untuk memperbaiki akhlak umat manusia. Dakwah di Indonesia tidak lepas dari sosok kyai yang dinilai mampu menginternalisasikan nilai-nilai ajaran Islam dalam sendi kehidupan masyarakat. Setiap kyai memiliki pola dakwak masing-masing dalam pendekatan dakwahnya sesuai kondisi sosio-kultural mad’unya, seperti yang dilakukan oleh ketiga kyai di Kecamatan Leces Kabupatan Probolinggo yaitu: Kyai Hasan, Kyai Abbas dan Kyai Barizi. Penelitian ini bertujuan untuk mengungkapkan tentang pola dakwah kyai dalam membangun sosio-religius masyarakat di Kecamatan Leces Kabupaten Probolinggo, dengan sub fokus mencakup: (1) peran dakwah kyai, (2) pola dakwah kyai, dan (3) tantangan serta hambatan dakwah kyai. Penelitian ini termasuk penelitian kualitatif yang menggunakan pendekatan analisis deskriptif dalam studi lapangan. Pengumpulan data dilakukan dengan cara observasi pengamat, wawancara mendalam, dan studi dokumentasi. Teknik analisis data meliputi reduksi data, penyajian data dan penarikan kesimpulan. Pengecekan keabsahan temuan dilakukan dengan triangulasi sumber dan triangulasi teknik. Hasil penelitian menunjukkan bahwa: (1) Kyai di Kecamatan Leces memiliki peran dakwah yang berbeda terhadap mad’unya. Kyai Hasan yang biasa diminta masyarakat untuk memimpin do’a, sedikit memberikan ilmu-ilmu syariat dalam kegiatan atau keadaan tertentu. Kyai Abbas yang tergolong kyai muda berperan sebagai penggerak masyarakat untuk mengikiuti majelis an-Nur. Sedangkan Kyai Barizi yang selain memimpin kegiatan keagamaan juga dipecaya sebagai bapaknya masyarakat yang menjadi pengayom, penggerak, dan problem solver yang dapat memecahkan permasalahan masyarakat. (2) Pola dakwah kyai di Kecamatan Leces memiliki strategi dan pendekatan yang berbeda berdasarkan kondisi sosio-kultural masyarakat dan juga dasar keilmuan dan pengalaman dari masing-masing kyai. Seperti pendekatan pengajian, pendidikan atau pesantren, thariqat atau spiritual dan Politik. (3) Setiap kyai di Kecamatan Leces mendapatkan hambatan dan tantangan dari mad’unya, meliputi: melakukan hal-hal yang kurang baik, niradab, kecenderungan pada kelompok atau kyai tertentu dan juga kurangnya solidaritas antar warganya. ABSTRACT Da'wah in Islam is the main activities of the development of Islam, which has always been in the outlook of scholars to improve the mankind morals. Da'wah in Indonesia can’t be separated from the figure of the kyai who is considered to internalizing the values of Islam in the joints of people's lives. Every kyai has his own da’wah pattern of his da'wah approach according to the socio-cultural conditions of his mad'u, as carried out by the three of kyai in Leces District, Probolinggo Regency, called Kyai Hasan, Kyai Abbas and Kyai Barizi. This study aims to reveal the pattern of da'wah in building socio-religious society in Leces District, Probolinggo Regency, with sub-focuses including: (1) the role of kyai da’wah (2) the pattern of kyai da’wah, (3) also the challenges and obstacles of kyai da’wah. This research is a qualitative study that uses a descriptive analysis approach. Data collection was carried out by means of observation, in-depth interviews, and documentation studies. Data analysis techniques include data reduction, presentation and conclusion. Checking the validity of the findings is done by triangulating sources and triangulating techniques. The results show that: (1) Kyai in Leces District have a different da'wah role towards their mad'u. Kyai Hasan, who is usually lead the community to prayers, gives a little knowledge of Shari'a Islam in certain activities or conditions. Kyai Abbas, who is classified as a young kyai, has a rule as a motivator for the community to join the an-Nur assembly. Meanwhile, Kyai Barizi, who apart from leading religious activities, is also believed to be the father of the community, who is the protector and problem solver. (2) The pattern of da'wah in Leces Sub-District has different strategies and approaches based on the socio-cultural conditions of the community as well as the scientific basis and experience of each kyai. Such as approaches to recitation, education or pesantren, tariqat or spirituality and politics. (3) Every kyai in Leces Subdistrict faces obstacles and challenges from his mad'u, including: doing things that are not good, non-compliant, tendencies towards certain groups or kyai and also a lack of solidarity among its members. مستخلص البحث أصبحت أنشطة الدعوة في الإسلام المحور الرئيسي لتطور الإسلام الذي كان في دائرة الضوء من العلماء لتصليح الأخلاق الإنسانية دائمًا. كانت الدعوة في إندونيسيا لا تنفصل عن شخصية الكياهي التي تستطيع على استيعاب قيم الإسلامية في حياة الناس. كل الكياهي له منهج الدعوة فيه وفقًا لحالته الاجتماعية والثقافية المجنون كما فعلهم الكياهي في منطقة ليجس فربولنجو و هم الكياهي حسن و الكياهي عباس و الكياهي بارزي. يهدف هذا البحث إلى الكشف عن نمط دعوة الكيهاء في بناء المجتمعات الاجتماعية الدينية في منطقة ليجس في فربولنجو مع التركيز على (1) دور دعوة الكياهي (2) تخطيط دعوة الكياهي (3) تحديات وعقبات دعوة الكياهي. يتضمن هذا البحث بحثًا نوعيًا بمنهج التحليل الوصفي في الدراسات الميدانية. يتم جمع البيانات عن طريق الملاحظة والمقابلات المتعمقة و التوثيق. تتضمن تقنيات تحليل البيانات تقليل البيانات وعرض البيانات ورسم الاستنتاجات. كان التحقق يتم من صحة النتائج عن طريق تثليث المصدر والتثليث التقني. أظهرت النتائج أن: (1) كان الكيهاء في ليجس له دور هام في الدعوة الإسلامية تجاه المدعو في المجتمع. مثل كياهي حسن، الذي يطلبه المجتمع في إمامة الدعاء لكثير من المجاليس وألقى العلوم الشريعة في المجاليس والأنشطة المجتمعية. وكذا كياهي عباس، له دور كبير في تحريك المجتمع وتنسيقه لمشاركة مجلس "النور". أما كياهي باريزي يعتبر أنه أبو المجتمع حيث يرئس ويُحَرِّكُ ويحامي ويُحِلُّ الْمُشكلاتِ فيهم. (2) إن نمط دعوة الكيهاء في ليجس لهم الاستراتيجيات والمناهج المختلفة حسب الظروف الاجتماعية والثقافية للمجتمع، وكذلك الأساس العلمي والخبرة للكيهاء. وذالك في كثير من التعاليم الدينية والمؤسسة التربوية والطريقة والسياسة. (3) يواجه كل كياي في ليجس عقبات وتحديات من المدعوين مثل الأفعال السيئة وسوء الأخلاق والتعصب الحزبية وعدم التضامن بين الناس

    Experiences and perspectives of adults on using opioids for pain management in the postoperative period : A scoping review protocol.

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    Funding The main reviewer (DA) is funded by Prince Sultan Military College of Health Sciences, Dhahran, Saudi Arabia and the Saudi Arabian Cultural Bureau in London, UK. This review will be part of DA’s PhD study at the University of Aberdeen.Peer reviewedPublisher PD

    Narcolepsy among Adults: A Descriptive Study

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