913 research outputs found

    Policy process and education reform in the Arab world

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    This paper explores and summarises the status, policies, challenges and reforms of the education systems in the Arab World. There is much that the systems have in common, especially in relation to cultural background, language and general strategies – this despite the striking differences that exist in the region in terms of the stage of development as reflected in such indicators as literacy rates, participation rates, gender issues, funding, and so on. The steady shift of the status of, and approach to education from being predominantly a social service reflecting mainly individual needs and human rights, and thus is mostly supply driven, to a balanced socioeconomic activity that incorporates the necessary aspects of a social service and economic investment has been a common phenomenon in Arab countries. One of the major developments in this respect is the growing privatisation and globalisation of educational services, especially in higher education. Modern technologies helped to support such developments and enhance a commodity approach with all its pros and cons which are clear mainly in distance and open education that utilises e-learning methodologies and which is spreading quickly, whether in open universities or as blended education in ordinary ones. The governance and structural aspects of the education systems in the Arab World have been characterised by some apparent weaknesses that are reflected in the ongoing efforts to improve their relevance to developmental needs and labour market requirements, enhance the decentralisation aspects and school empowerment, and develop the technical and vocational education systems. The relatively high population growth rate, coupled with the phenomenon of mass education and the lack of resources in the majority of Arab countries, have reflected negatively on the qualitative aspects of educational efforts and services, and have resulted, in many cases, in poor efficiency. This is clear for example in the modest achievements in the field of scientific research. In the educational field, the Arab World does not lack regional and sub-regional organisations and set-ups, although the effectiveness of such organisations has so far been subject to criticism despite many distinct efforts and achievements.peer-reviewe

    LES Modelling of Propagating Turbulence Premixed Flames using a Dynamic Flame Surface Density Model

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    A Dynamic flame surface density (DFSD) model, developed recently from experimental images for transient turbulent premixed flames, is implemented and tested using the large eddy simulation (LES) modelling technique. Numerical predictions from DFSD model are compared with those predicted using the flame surface density (FSD) sub-grid scale (SGS) model for reaction rate. In the SGS-DFSD model, dynamic formulation of the reaction rate is coupled with the fractal analysis of the flame front structure. The fractal dimension is evaluated dynamically from an empirical formula based on the sub-grid velocity fluctuations. A laboratory scale combustion chamber with inbuilt solid obstacles is used for model validation and comparisons. The flame is initiated from igniting a stichiometric propane/air mixture from stagnation. The results obtained with the DFSD model are in good comparisons with experimental data and the essential features of turbulent premixed combustion are well captured. It has also been observed that the SGS-DFSD model for reaction rate found to capture the unresolved flame surface density contributions. Further investigations are planned to examine and validate of the SGS-DFSD for different flow geometries

    Synthetic Aperture Focusing Technique Using the Envelope Function for Ultrasonic Imaging

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    In traditional ultrasonic imaging systems, a transducer is scanned across the surface of a specimen at constant intervals. Synthetic aperture focusing techniques (SAFT) have been utilized extensively to process the RF data in order to enhance the signal-to-noise ratio of the image [1]. However, the implementation of the algorithm using sampled RF data has the disadvantage of requiring large memory and high-speed devices. These requirements can be reduced by using the envelope of the RF signal which involves processing the baseband signal. The envelope detection can be easily implemented as part of the receiver circuit

    Penggunaan Media Edu-Game Berbasis Ular Tangga Fisika dalam Pembelajaran Materi Gelombang pada Siswa Kelas XI SMA Negeri 1 Gorontalo

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    Penelitian ini bertujuan untuk mengetahui penggunaan media edu-game berbasis ular tangga Fisika dalam materi gelombang. Jenis penelitian yang digunakan pada penelitian ini adalah penelitan deskriptif dengan menggunakan pendekatan kuantitatif. Berdasarkan data yang diperoleh untuk lembar observasi aktivitas guru pada pertemuan I persentase aktivitas guru tercapai 95.2 %, pertemuan II tercapai 97.6 %, dan pertemuan III tercapai 98.8 %, sedangkan persentase aktivitas peserta didik pada pertemuan I tercapai 94.2 %, pertemuan II tercapai 96.8 %, dan pertemuan III tercapai 98 %. Angket minat peserta didik untuk indikator perasaan senang diperoleh rata-rata persentase 97.4 %, indikator perhatian diperoleh persentase rata-rata 94 %, indikator ketertarikan diperoleh rata-rata persentase 93.4 %, dan indikator keterlibatan peserta didik dalam belajar diperoleh rata-rata persentase 96 %. Hasil belajar peserta didik pada materi gelombang setelah diajarkan menggunakan media edu-game berbasis ular tangga Fisika dapat dilihat bahwa dari 30 orang peserta didik, 29 orang yang memenuhi KKM dan 1 orang yang tidak memenuhi KKM. Oleh karena itu, penggunaan media edu-game berbasis ular tangga Fisika pada pembelajaran materi gelombang pada peserta didik kelas XI IPA3 SMA Negeri 1 Gorontalo sudah maksimal atau sangat baik

    Hybrid Wind Speed Prediction Model Using Intrinsic Mode Function (IMF) and Gradient Boosted Machine (GBM)

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    Before sitting a wind turbine, reliable wind speed prediction is prerequisite requirements that must be performed in order to get optimum energy yield. Single model has a lot of constraints in terms of prediction accuracy, to solve this persistent problem, this paper presents the application of hybrid model based on IMF and GBM so as to predict the wind speed in the areas with limited or absent of data. In the first place, the observed wind speed was decomposed into six using IMF in order to reduce ill-define stochastic nature of wind speed. The decomposed wind speed was used to train, test and validate the model developed GMB model which was developed in a Matlab environment. The final predicted values are obtained by summing all the individual prediction sub models. Wind speed data observed in the existing wind stations in Sarawak for a period of 1 year from 2017 to 2018 were used for the simulation. The model implementation confirmed that the proposed model is robust and capable to predict wind speed in remote and rural areas. A comparison with conventional method (ARIMA) was further investigated, the results showed the superiority of the new hybrid model over ARIMA

    Time Resolved Correlation measurements of temporally heterogeneous dynamics

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    Time Resolved Correlation (TRC) is a recently introduced light scattering technique that allows to detect and quantify dynamic heterogeneities. The technique is based on the analysis of the temporal evolution of the speckle pattern generated by the light scattered by a sample, which is quantified by c_I(t,τ)c\_I(t,\tau), the degree of correlation between speckle images recorded at time tt and t+τt+\tau. Heterogeneous dynamics results in significant fluctuations of c_I(t,τ)c\_I(t,\tau) with time tt. We describe how to optimize TRC measurements and how to detect and avoid possible artifacts. The statistical properties of the fluctuations of c_Ic\_I are analyzed by studying their variance, probability distribution function, and time autocorrelation function. We show that these quantities are affected by a noise contribution due to the finite number NN of detected speckles. We propose and demonstrate a method to correct for the noise contribution, based on a N→∞N\to \infty extrapolation scheme. Examples from both homogeneous and heterogeneous dynamics are provided. Connections with recent numerical and analytical works on heterogeneous glassy dynamics are briefly discussed.Comment: 19 pages, 15 figures. Submitted to PR

    How to Stop Spread of Misinformation on Social Media: Facebook Plans vs. Right-click Authenticate Approach

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    One of the key features of social networks is that users are able to share information, and through cascades of sharing information, this information may reach a large number of individuals. The high availability of user-provided contents on online social media facilitates people aggregation around shared beliefs, interests, worldviews and narratives. With lack of means to verify information, social media has been accused of becoming a hot bed for sharing of misinformation. Facebook, as one of the largest social networking services, has been facing widespread criticism on how its newsfeed algorithm is designed thus amplifying dissemination of misinformation. In late 2016, Facebook revealed plans to address fake news on Facebook newsfeeds. In this work, we study the methods Facebook has proposed to combat the spread of misinformation and compare it with our previously proposed approach called `Right-click Authenticate'. By analyzing the Business Process Modeling and Notation of both approaches, this paper suggests some key weaknesses and improvements social media companies need to consider when tackling the spread of misinformation online
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