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A derivation for the finite element equations of consolidation by the principle of virtual work and virtual complementary work is presented. This provides a simple alternative to derivation by variational principles or the Laplace transform. In the final part of the paper the equations are rearranged into a form suitable for time stepping for non‐linear applications.

Elasto‐plastic models based on critical state formulations have been successful in describing many of the most important features of the mechanical behaviour of soils. This review paper deals with the applications of this class of models to the numerical analysis of geotechnical problems. After a brief overview of the development of the models, the basic critical state formulation is presented together with the main modifications which have actually been used in computational applications. The problems associated with the numerical implementation of this type of models are then discussed. Finally, a summary of reported computational applications and some specific examples of analyses of geotechnical problems using critical state models are presented.

This chapter presents the impact of the Covid-19 pandemic on the course of studies and life career skills development of undergraduate students at the University of Macedonia, a mid-sized public Greek University. It describes a multivariate methodology research that investigated how the students, first-hand experienced the unexpected changes from face-to-face on campus to synchronous online education during the lockdown and how they coped with these changes. Change is considered and described as a main component within current life and career trajectories addressing chaotic and unpredictable circumstances while Chaos Theory of Careers (CTC) offers the theoretical background of the chapter. The research followed the mixed methods paradigm: a multilevel embedded sequential explanatory design including a participant selection model and multivariate data analysis methods. A survey (N = 621) was conducted; individual interviews and focus groups’ discussions further explained the quantitative findings. The emerging clusters of students revealed similarities in feelings, motivation, adaptation, and life career skills development. The first cluster comprised of older, digitally high-skilled students, with the required technological equipment, adaptable to change, self-regulated, strongly in favor of synchronous online education; in the second cluster were grouped the younger, digitally medium-skilled students, who regularly participated in both modalities, critically recognized the advantages of either one, feeling strongly in favor of a combination; finally, the third cluster included digitally medium-skilled students who found serious difficulty in using online platforms, dissatisfied with social isolation and distant interaction, strongly preferring face-to-face instruction, valuing direct physical contact, social connection, and networking.

Contact problems are among the most difficult ones in mechanics. Due to its practical importance, the problem has been receiving extensive research work over the years. The finite element method has been widely used to solve contact problems with various grades of complexity. Great progress has been made on both theoretical studies and engineering applications. This paper reviews some of the main developments in contact theories and finite element solution techniques for static contact problems. Classical and variational formulations of the problem are first given and then finite element solution techniques are reviewed. Available constraint methods, friction laws and contact searching algorithms are also briefly described. At the end of the paper, a bibliography is included, listing about seven hundred papers which are related to static contact problems and have been published in various journals and conference proceedings from 1976.

Access to education has been globalized and democratized to a certain extent through massive open online courses (MOOCs) and other open-access platforms and content databases. In a recent study by Inayatullah and Milojević (2014), the recommendations were to establish a pilot project, enhance digital pedagogy and learning, customize degrees, create a culture of change in higher education, enhance collaboration, support research activities, redefine frames of reference, and anticipate and prepare for futures trends. The need for democratization of education has been increasing to meet the need of individuals and groups to assert and highlight their identity and role in society. Education is the means to facilitate this through a practical and active approach through wider stakeholder participation. Religious belief was identified as the main cause of conflicts among multi-ethnic cohorts. Adding socio-cultural differences to the mix and uncontrolled access to various opinions through social media makes the task much more complex. Educational policies must consider mother-tongue learning to improve learning outcomes. However, making the vast learning content accessible in multiple languages could be daunting. This chapter explores these emerging challenges and changing stakeholder expectations from the formal education system. The policy implications, possible technology-driven solutions, and their effectiveness in addressing the growing challenges of a global learning village have been explored.

This paper presents a numerical investigation of the interaction of surfaces radiation with developing laminar free convective heat transfer in a divided vertical channel. The influence of the radiation on the heat transfer and on the air flow is studied for various sizes (width and length) of the plate.

The specifically developed numerical code is based on the utilization of the finite volume method. The SIMPLER algorithm for the pressure‐velocity coupling is adopted. The view factors are determined by using boundary elements to fit the surfaces, an algorithm solving the shadow effect and a Monte Carlo method for the numerical integrations.

Results obtained show that the radiation: plays a very important role on the paces of the isotherms, especially at Ra≥1,600; increases considerably the average wall Nusselt number; and increases the mass flow rate and the average channel Nusselt number at high Rayleigh numbers. The plate location has a significant effect on the heat transfer only in presence of the radiation exchange. The increase of both length and width of the plate causes a decrease of the heat transfer and the mass flow rate.

The use of the code is limited to the flow that is assumed to be incompressible, laminar and two dimensional. The radiative surfaces are assumed diffuse‐gray.

Natural convection in vertical channels formed by parallel plates has received significant attention because of its interest and importance in industrial applications. Some applications are solar collectors, fire research, electronic cooling, aeronautics, chemical apparatus, building constructions, nuclear engineering, etc.

In comparison to the most of the previous studies on natural convection in partitioned channels, the radiation exchange was neglected. This study takes into account the radiation exchange in a divided channel.

A simple procedure for accurate calculation of pore pressures in undrained elasto‐plastic materials is described. An 8‐node element is used, with ‘reduced’ integration during stress redistribution, and ‘full’ integration to form the global stiffness matrix for the modified Newton—Raphson procedure. An analysis of passive earth pressure in an undrained soil is used to demonstrate the algorithm and computed results are compared with a closed‐form solution.

The effect of a rectangular obstruction of different sizes on natural convection heat transfer in the case of a vertical channel has been analysed for T boundary conditions on the walls. A comparison of the Nusselt number values with those for plane channel is presented. For smaller obstruction depths and for asymmetric heating, there is not much variation of the results from a case of channel with a baffle for asymmetric heating. For large obstruction depths, the flow conditions show a behaviour similar to that of a channel with a backward‐facing step.

The concept of innovation should not be reduced to its technological dimension but encompasses the whole context of its deployment and implementation. Regardless of technology, an innovation may be successful or not depending on how well its implementation suits each single context. In the case of education, this consists, to a sizeable extent, in a communicational and interpersonal context. The hypothesis of this piece is that maintaining optimal communication between participants is a key factor of success of new online teaching methods. Given that in this regard, there are similarities between negotiating practice and teaching practice, it is worth examining whether good practices developed in online international negotiation are transferable to online teaching. The chapter identifies a number of practices from online negotiation that perform well in online teaching. It focuses on communicational aspects, mutual understanding (monitoring and optimization of understanding), motivation to listen, attention, active participation, and non-verbal communication. Online teaching and online negotiation share another common feature: some unresolved challenges are common to both disciplines. This should also be taken into account when migrating educational programmes online. The research is informed by the author's first-hand experience from practice in both international diplomatic negotiation and academic teaching.

In this paper the authors have sought to create solid connection between theory and practices pertaining to the immense value of students' emotional engagement in online instruction. This conceptual paper is motivated by the inadequacy of literature translating the emotional engagement concept to the micro level of online instructions within the upsurge intention to the new trend of online teaching-learning. This paper aims to contribute by addressing the fundamental issues of emotional engagement starting from revisiting the roles of teachers in students' emotional engagement, reviewing and underscoring the importance of students' emotional engagement in higher education and finally conceptualizing and framing how to infuse emotional engagement into the instructions.

The explanation of how to advocate for students' emotional engagement in online learning praxis is inadequately discussed although the library of literature has informed the fundamental role of students' emotional engagement in establishing successful online learning. This paper aims to address this practical need by interactively connecting the theory, empirical findings and pedagogical practices in the area to provide praxeological contribution to the development of quality online teaching-learning practices.

This study presents a framework that advances the existing body of research at the juncture of emotional engagement and online learning. This conceptual paper foregrounds an examination of the roles of teachers in students' emotional engagement and underscores the significance of students' emotional engagement in higher education. Moreover, it proposes a conceptual framework delineating effective strategies for the integration of emotional engagement within instructional methodologies. This framework comprises four key aspects: (1) fostering students' learning autonomy and ownership, (2) establishing socioemotional construction through verbal and non-verbal expressions, (3) integrating a multimodal approach to online learning and (4) honing the art of constructive feedback.

This conceptual paper is rooted in a nested theory and draws upon empirical studies. While the presented framework holds promise, its efficacy in the classroom setting requires validation through further empirical investigation.

Those proposed pedagogical strategies detailed with the practical examples explained in the previous part would afford students with a better socioemotional amenities of learning environment benefitting them with positive affective engagement.

Given the imperative to enhance students' emotional engagement in online learning and the limited discourse surrounding its practical implementation, the proposed framework stands poised to enrich and inform online pedagogical practices.