908 research outputs found
Policy process and education reform in the Arab world
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
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
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Client-server-based LBS architecture: A novel positioning module for improved positioning performance
Permission to distribute obtained from publisher.This work presents a new efficient positioning module that operates over client-server LBS architectures. The
aim of the proposed module is to fulfil the position information requirements for LBS pedestrian applications
by ensuring the availability of reliable, highly accurate and precise position solutions based on GPS single
frequency (L1) positioning service. The positioning module operates at both LBS architecture sides; the client
(mobile device), and the server (positioning server). At the server side, the positioning module is responsible
for correcting user’s location information based on WADGPS corrections. In addition, at the mobile side,
the positioning module is continually in charge for monitoring the integrity and available of the position
solutions as well as managing the communication with the server. The integrity monitoring was based on
EGNOS integrity methods. A prototype of the proposed module was developed and used in experimental trials
to evaluate the efficiency of the module in terms of the achieved positioning performance. The positioning
module was capable of achieving a horizontal accuracy of less than 2 meters with a 95% confidence level
with integrity improvement of more than 30% from existing GPS/EGNOS services
Synthetic Aperture Focusing Technique Using the Envelope Function for Ultrasonic Imaging
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
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)
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
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
, the degree of correlation between speckle images recorded at
time and . Heterogeneous dynamics results in significant
fluctuations of with time . We describe how to optimize TRC
measurements and how to detect and avoid possible artifacts. The statistical
properties of the fluctuations of 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 of detected speckles. We propose and demonstrate a method to
correct for the noise contribution, based on a 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
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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