A Survey on Teachers’ Awareness and Attitudes on Computer-corpus Data: An Assisted Technology-based EFL Vocabulary Selection and Instruction Source

AbstractThe present research paper focuses on the area of vocabulary teaching in the foreign language classroom. It attempts to highlight the way computer corpus data ease the difficulties involved in EFL (English Foreign Language) vocabulary teaching and learning. The paper aims at exploring the extent of awareness of EFL teachers to the concept of computer corpus-data, raising awareness on the efficacy of computer-corpus data in the area of EFL vocabulary selection and instruction and analyzing teachers’ attitudes on the application of those data as a language source in selecting EFL vocabulary teaching materials

Improvement of the Mechanical Behavior of Composite Materials with Different Binders Based on Local Plant Fibers Alfa and Diss

Concerned about the environmental and economic impact, composite materials are increasingly used in the construction sector. Indeed, the use of plant fibers as reinforcement in construction materials have been the subject of several researches in recent years; the main motivation is the weight gain combined with high mechanical characteristics. The objective of this research concerns the study of the physicomechanical properties of composite materials with cement and clay matrices reinforced with Alfa and Diss fibers with dimensions ranging from 2 to 8 cm. This involves evaluating the performance of these materials according to the formulation, for a volume ratio (Alfa or Diss / Matrix fibers equal to 4), using dry fibers and pre-wetted fibers. The study of the mechanical properties showed a drop of the performance for both compression and bending strength compared to the reference material without adding fibers (cement or clay paste). It should be noted that the best mechanical performance is obtained for the case of composites materials with cementitious matrix with pre-wetted fibers. On the other hand, in the case of composites with clayey matrices, pre-wetting does not improve the mechanical characteristics. It is also noted that the best dimensions of fibers which improve the mechanical characteristics in bending are generally 6 cm for composites with a clay matrix and between 2 and 4 cm for cementitious composites. In all cases, the fibers in composite materials with cement or clay matrix create a bridging effect, making it possible to limit the progression of cracks during loading. This phenomenon gives to the various composite materials a ductile behavior

Mechanical behaviour of Composites based on Diss and Aflfa fibres in different matrices

The use of natural fibers in cementitious matrices has an incompatibility, which results considerable retardation of setting and very low resistances during the composite tests with natural crushed Diss, despite the fact that the fibers have considerable tensile strengths, because of the sugars and water- soluble components contained in natural plants. To improve the fibers contribution in cementitious composites, we have carried out a treatment by boiling the natural fibers to extract the substances responsible for the bad connection between fibers and the cement paste. This phenomenon of incompatibility disappears with the use of clay matrix or lime, which allows using the fibers without any treatment. We were able to determine the mechanical behavior of composites in flexion and compression by measuring stresses and deformations. Through our vast experimental program on the composites of natural fibers of Alfa and Diss in different matrices (cement and clay) and different sizes ranging from 2 to 8 cm, we have found: 1) The best resistance in bending and compression are generally reached for the composites with fibers having the dimensions between 4 and 6 cm. 2) The best bending strengths are achieved for composites with cementitious matrices, because of the good adhesion of the fibers to the matrix. 3) The best compressive strengths are achieved for clay matrix composites, which are due to the good compressibility of the clay. 4) The composites of Alfa and Diss fibers presented a very ductile behavior as well in flexion as in compression, contrary to the pure binder paste which has a brittle behavior. 5) The composites obtained have a very low density, which makes it possible to classify them as lightweight materials and have a very ductile behavior, which suggests using these materials as filling in the seismic zones

Mechanical behaviour of Composites based on Diss and Aflfa fibres in different matrices

The use of natural fibers in cementitious matrices has an incompatibility, which results considerable retardation of setting and very low resistances during the composite tests with natural crushed Diss, despite the fact that the fibers have considerable tensile strengths, because of the sugars and water- soluble components contained in natural plants. To improve the fibers contribution in cementitious composites, we have carried out a treatment by boiling the natural fibers to extract the substances responsible for the bad connection between fibers and the cement paste. This phenomenon of incompatibility disappears with the use of clay matrix or lime, which allows using the fibers without any treatment. We were able to determine the mechanical behavior of composites in flexion and compression by measuring stresses and deformations. Through our vast experimental program on the composites of natural fibers of Alfa and Diss in different matrices (cement and clay) and different sizes ranging from 2 to 8 cm, we have found: 1) The best resistance in bending and compression are generally reached for the composites with fibers having the dimensions between 4 and 6 cm. 2) The best bending strengths are achieved for composites with cementitious matrices, because of the good adhesion of the fibers to the matrix. 3) The best compressive strengths are achieved for clay matrix composites, which are due to the good compressibility of the clay. 4) The composites of Alfa and Diss fibers presented a very ductile behavior as well in flexion as in compression, contrary to the pure binder paste which has a brittle behavior. 5) The composites obtained have a very low density, which makes it possible to classify them as lightweight materials and have a very ductile behavior, which suggests using these materials as filling in the seismic zones

Abstracts of 1st International Conference on Computational & Applied Physics

This book contains the abstracts of the papers presented at the International Conference on Computational & Applied Physics (ICCAP’2021) Organized by the Surfaces, Interfaces and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria, held on 26–28 September 2021. The Conference had a variety of Plenary Lectures, Oral sessions, and E-Poster Presentations. Conference Title: 1st International Conference on Computational & Applied PhysicsConference Acronym: ICCAP’2021Conference Date: 26–28 September 2021Conference Location: Online (Virtual Conference)Conference Organizer: Surfaces, Interfaces, and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria