Fracture parameters formulation for single edge notched AS4 stitched warp-knit fabric composite plate

The three-dimensional problem of the fracture for the single edge notched tension plate (SENT) of orthotropic material is considered in this paper. The finite element solution is used to evaluate the singular and non-singular terms of the William series, i.e. Stress intensity factor (SIF) and T-stresses namely T11, T13 and T33. Based on the obtained numerical results, a fitting procedure is performed in order to propose analytical formulations giving the fracture parameters near the crack tip. The obtained results are in good agreement with the finite elements calculation and other literature results

Fracture parameters formulation for single edge notched AS4 stitched warp-knit fabric composite plate

The three-dimensional problem of the fracture for the single edge notched tension plate (SENT) of orthotropic material is considered in this paper. The finite element solution is used to evaluate the singular and non-singular terms of the William series, i.e. Stress intensity factor (SIF) and T-stresses namely T11, T13 and T33. Based on the obtained numerical results, a fitting procedure is performed in order to propose analytical formulations giving the fracture parameters near the crack tip. The obtained results are in good agreement with the finite elements calculation and other literature results

Fracture parameters formulation for single edge notched AS4 stitched warp-knit fabric composite plate

The three-dimensional problem of the fracture for the single edge notched tension plate (SENT) of orthotropic material is considered in this paper. The finite element solution is used to evaluate the singular and non-singular terms of the William series, i.e. Stress intensity factor (SIF) and T-stresses namely T11, T13 and T33. Based on the obtained numerical results, a fitting procedure is performed in order to propose analytical formulations giving the fracture parameters near the crack tip. The obtained results are in good agreement with the finite elements calculation and other literature results

Extracted Electronic Parameters of a Novel Ag/SnO2:In/Si/Au Schottky Diode for Solar Cell Application

The effect of indium on the characteristics of Ag / SnO2 : In / Si / Au Schottky diode (SD) is studied. The electronic parameters, ideal factor, the effective barrier, flat band barrier height, the series resistance, the saturation current density of the diodes were extracted from the current voltage (I-V) and capacitance voltage (C-V) characteristics. The series resistance (Rs) determined by Cheung method increases (508-534 Ω) with In doping level while the barrier height still constant around 0.57 V. Norde approximation gives a similar barrier height values of 0.69 V but the series resistance reaches higher values of 5500 Ω

Range entropy: A bridge between signal complexity and self-similarity

Approximate entropy (ApEn) and sample entropy (SampEn) are widely used for temporal complexity analysis of real-world phenomena. However, their relationship with the Hurst exponent as a measure of self-similarity is not widely studied. Additionally, ApEn and SampEn are susceptible to signal amplitude changes. A common practice for addressing this issue is to correct their input signal amplitude by its standard deviation. In this study, we first show, using simulations, that ApEn and SampEn are related to the Hurst exponent in their tolerance r and embedding dimension m parameters. We then propose a modification to ApEn and SampEn called range entropy or RangeEn. We show that RangeEn is more robust to nonstationary signal changes, and it has a more linear relationship with the Hurst exponent, compared to ApEn and SampEn. RangeEn is bounded in the tolerance r-plane between 0 (maximum entropy) and 1 (minimum entropy) and it has no need for signal amplitude correction. Finally, we demonstrate the clinical usefulness of signal entropy measures for characterisation of epileptic EEG data as a real-world example.Comment: This is the revised and published version in Entrop

Numerical Analysis of Plate Thickness Effect on Residual Stress Distribution around a Cold Expanded Hole

The process of cold expansion creates compressive stresses around the mounting hole, which can help to reduce stress concentrations during the loading of a structure. A numerical simulation using the finite element method was conducted to analyse the effect of cold expansion on perforated plates of different thicknesses. The simulation considered the thickness of the plate and the tapered mandrel and examined the induced residual stresses. The results showed that the magnitude of the circumferential residual stresses varied depending on the thickness of the plate and that the extent of the zone of compressive stresses was strongly affected by the plate thickness. These findings are particularly relevant to the optimisation of the cold expansion process, as the optimal parameters for a particular plate thickness may not be optimal for some other thickness. Therefore, the results of this study can guide the optimisation of the cold expansion process for different plate thicknesses

Arabic language maintenance among the Arabic-speaking community in the regional Queensland city of Toowoomba, Australia

This research project explores language maintenance efforts, experiences and challenges faced by the Arabic-speaking community in the regional Queensland city of Toowoomba, Australia. The purpose of this inquiry was to identify issues that might have contributed to or prevented the maintenance of Arabic language among Arabic speakers. The theoretical framework was developed by the researcher from several existing language maintenance theories and models. A qualitative approach was selected to investigate the language maintenance phenomenon through engaging in the everyday life of the Arabic speakers. Additionally, a descriptive and interpretive ethnography was applied to understand this community from insider and outsider perspectives, aiming to enhance the quality and richness of the results. Data were collected through participant observations, in-depth semi-structured interviews with 20 adult individuals, and a research journal. Subsequently, a thematic analysis was undertaken which involved organizing, exploring and coding the data into several themes, and displaying and interpreting the data to answer the research questions. The emerging themes informed the findings of this study to answer the research questions. The conclusions of this research are envisaged to enrich the knowledge and theories of language maintenance and raise awareness of the Arabic speakers and the community about the importance of maintaining their language

I AM NOT READY FOR TEACHING! EFL GRADUATES’ CHALLENGES AND EXPECTATIONS OF THE PROFESSION

Every school year, Algerian Ministry of Education recruits hundreds of university Masters’ graduates to occupy job vacancies in teaching English both in Middle and Secondary schools. However, student teachers who eventually become novice teachers are often blamed of being unprepared and unqualified for the profession. Student teachers alike express their dissatisfaction with the quality of teacher education they have received and the lack of training in different areas of teaching.  This exploratory paper seeks to investigate the level of readiness and preview the forecasted challenges that university graduates of English may encounter as they enter the school life. To do so, a questionnaire was administered to 136 Masters’ graduates of English at Biskra University to survey their major challenges and expectations of the teaching profession. The results revealed that a considerable number of student teachers are reluctant to join schools as they feel ill-equipped and untrained to become teachers though they see teaching as a promising job for the future. They also express their need to have pre-service teacher training sessions along their studies in which core elements of teaching need to be practiced and simulated especially lesson planning, classroom management and teaching language skills. The surveyed student teachers expressed their uncertainties of dealing with learners’ discipline problems in large classes especially in Secondary Schools, and preparing lessons from a textbook they have never trained to work with. For better insights into novice teachers’ challenges, a classroom observation-based enquiry and one-on-one interviews with beginning teachers may reveal further difficulties and suggest better recommendations