Context in Mobile learning: the point of view of the learners

Context-awareness is becoming a crucial component in the mobile learning systems due to the dynamic changing of the Mobile learning environment, a Context-aware mobile learning system senses mobile environment and reacts to changing context during the learning process. Some efforts have been made in the area of Context-aware Mobile learning systems in order to propose a user model, most of them are focusing on the technological context such as the network performances, mobile devices capabilities, others are focusing on the learners’ style and preferences, and no one tried to understand the learners’ needs. However, no one tried to study the Learning context from the point of view of the learners. For this purpose, we created a questionnaire, in which we tried to understand which learning contexts are important to the learners in the learning process, and we use it to understand their needs and preferences, to inform the design of a new Context aware Mobile Learning Approach

A Partitioned Fluid-Structure Interaction Approach during Steel Solidification: Application to the Simulation of Ingot Casting

International audienceOne of the critical challenges encountered when modeling a thermo-mechanical problem in the context of steel casting processes, is to achieve a concurrent and efficient computation of fluid flow (ingot mould filling, nozzle jet in continuous casting) and solid mechanics (stress-strain in solidified regions). This is of crucial importance in industry for the prediction of surface or sub-surface cracks for instance that may initiate in solidified regions during the filling stage of ingot casting, or in the mould region during continuous casting. The current state-of-the-art [15-17-21] consists in separating the analysis in two distinct stages: fluid flow using CFD codes and stress-strain analysis using structural codes. This induces several drawbacks regarding practical use and computational efficiency. A monolithic formulation, treating the fluid-solid interaction (FSI) may be investigated but is not adapted to the context of solidification, because of huge differences between liquid viscosity and solid consistency. It is then preferable to consider this FSI problem as a weak interaction problem, for which a partitioned formulation is more efficient than a monolithic one. Therefore, a two-step resolution strategy combining fluid flow and solid mechanics has been developed. Liquid flow (natural convection or filling flow), thermal dilatation as well as thermally induced deformation of the solid phase are accounted for

The impact of economic recovery programs on indicators of economic welfare in Algeria -An econometric study using the ARDL model for the period 2000-2020-

عمدت الجزائر في ظل البحبوحة المالية التي حققتها نتيجة ارتفاع أسعار النفط الى تعميم إستراتيجية بعيدة المدى من خلال تقصي سياسة توسعية تهدف الي بعث ديناميكية الاستثمار على النحو الكفيل بإنعاش المؤشرات الإقتصادية الكلية والعمل على رفع الكفاءة الاستيعابية للاقتصاد الجزائري. لذا، تهدف هذه الدراسة إلى تحديد العلاقة قصيرة وطويلة المدى بين الانفاق الحكومي ونصيب الفرد من الناتج الداخلي الخام (مؤشر الرفاهية) خلال الفترة 2000-2020، باستخدام نموذج ARDL، وخلصت الدراسة القياسية إلى أن الإنفاق العام له تأثير إيجابي على نصيب الفرد من الناتج المحلي الإجمالي فقط على المدى الطويل بنسبة 55٪، والنموذج المقدر ليس به مشاكل في الاقتصاد القياسي.In light of the financial surpluses that it achieved as a result of the high oil prices, Algeria proceeded to generalize a long-run strategy through the application of an expansionary policy aimed at reviving investment dynamism in a way that would ensure the revival of macroeconomic indicators and work to raise the absorptive efficiency of the Algerian economy. Therefore, This Study aims to determine the short and long-run relationship between public expenditures and per capita gross domestic product (welfare index), during the period 2000-2020, using the ARDL model.  The econometric study concluded that public expenditures have a positive impact on the per capita GDP only in the long run by 55%. In addition to, The estimated model has no econometric problems

Co-crystal structures of furosemide:urea and carbamazepine:indomethacin determined from powder x-ray diffraction data

Co-crystallization is a promising approach to improving both the solubility and the dissolution rate of active pharmaceutical ingredients. Crystal structure determination from powder diffraction data plays an important role in determining co-crystal structures, especially those generated by mechanochemical means. Here, two new structures of pharmaceutical interest are reported: a 1:1 co‑crystal of furosemide with urea formed by liquid-assisted grinding and a second polymorphic form of a 1:1 co‑crystal of carbamazepine with indomethacin, formed by solvent evaporation. Energy minimization using dispersion-corrected density functional theory was used in finalizing both structures. In the case of carbamazepine:indomethacin, this energy minimization step was essential in obtaining a satisfactory final Rietveld refinement

Online Prediction of Nonlinear Signal Processing Problems Based Kernel Adaptive Filtering

This paper presents two of the most knowing kernel adaptive filtering (KAF) approaches, the kernel least mean squares and the kernel recursive least squares, in order to predict a new output of nonlinear signal processing. Both of these methods implement a nonlinear transfer function using kernel methods in a particular space named reproducing kernel Hilbert space (RKHS) where the model is a linear combination of kernel functions applied to transform the observed data from the input space to a high dimensional feature space of vectors, this idea known as the kernel trick. Then KAF is the developing filters in RKHS. We use two nonlinear signal processing problems, Mackey Glass chaotic time series prediction and nonlinear channel equalization to figure the performance of the approaches presented and finally to result which of them is the adapted one

A partitioned resolution for concurrent fluid flow and stress analysis during solidification: application to steel ingot casting

International audienceIn simulation of solidification processes, an open issue is the concurrent modelling of fluid flow and solid mechanics. This is critical for the prediction of cracks formed in solidified regions during the filling stage of ingot casting, or in the mould during continuous casting. The proposed approach consists of a partitioned two-step resolution strategy

A Dynamic and Adaptable Service Composition Architecture in the Cloud Based on Multi-Agent Systems

Nowadays, service composition is one of the major problems in the Cloud due to the exceptional growth in the number of services deployed by providers. Recently, atomic services have been found to be unable to deal with all client requirements. Traditional service composition gives the clients a composite service without non-functional parameters. To respond to both functional and non-functional parameters, we need a service composition. Since web services cannot communicate with each other or participate dynamically to handle changes service parameters in service composition, this issue has led us to use a dynamic entity represented by an agent based on dynamic architecture. This work proposes an agent-based architecture with a new cooperation protocol that can offer an automatic and adaptable service composition by providing a composite service with the maximum quality of service. The implementation of this model has been provided in order to evaluate the authors' system. The obtained results demonstrate the effectiveness of their proposed system

A Self-adaptive Agent-based System for Cloud Platforms

Cloud computing is a model for enabling on-demand network access to a shared pool of computing resources, that can be dynamically allocated and released with minimal effort. However, this task can be complex in highly dynamic environments with various resources to allocate for an increasing number of different users requirements. In this work, we propose a Cloud architecture based on a multi-agent system exhibiting a self-adaptive behavior to address the dynamic resource allocation. This self-adaptive system follows a MAPE-K approach to reason and act, according to QoS, Cloud service information, and propagated run-time information, to detect QoS degradation and make better resource allocation decisions. We validate our proposed Cloud architecture by simulation. Results show that it can properly allocate resources to reduce energy consumption, while satisfying the users demanded QoS

CFD Simulation With Ansys Effect Of Twisted Tape Ratio On Nusselt Number and Reynold Number Solar Collector

Solar collector is one of the tools used to harness solar power and then convert it into heat which is used to heat water. The solar collector used is a flat plate type solar collector, the drawback of this solar collector is its low efficiency value. One method that can be used to increase its efficiency is to add twisted tape. Twisted tape serves to increase the value of the nusselt number and reynold number, where the increasing nusselt number and reynold number means the efficiency will increase, the Twisted Tape Ratio is the ratio between the distance of two peaks (H) and the width of the pipe (D). In this study using three variations of the tape ratio, namely 5,4, and 3, at Y = 5 the highest nusselt value and the Reynold number 4000 and Nuselt Number 24 were used, this is because the Twisted Tape ratio is 4 and 3 forms of twisted tape inhibit the flow. which causes a decrease in the value of the nusselt number and reynold number