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The purpose of this paper is to study the mechanical behavior in fatigue tensile mode of different cross-ply laminates constituted of unidirectional carbon fibers, hybrid fibers and glass fibers in an epoxy matrix; and to identify and characterize the local damage in the laminated materials with the use of the acoustic emission (AE) technique.

The tests in the fatigue mode permitted the determination of the effect of the stacking sequences, thickness of 90° oriented layers and reinforcement types on the fatigue mechanical behavior of the laminated materials. The damage investigation in those materials is reached with the analysis of AE signals collected from fatigue tensile tests.

The results show the effects of reinforcement type, stacking sequences and thicknesses ratio of 90° and 0° layers on the mechanical behavior. A cluster analysis of AE data is achieved and the resulting clusters are correlated with the damage mechanism of specimens under loading tests.

The analysis of AE signals collected from tensile tests of the fatigue failure load allows the damage investigation in different types of cross-ply laminates which are differentiated by the reinforcement type, stacking sequences and thicknesses ratio of 90° and 0° layers.

European Educational Policies have been studied not only from an economic and political approach but also from an educational and cultural one. On this basis, and according to the contemporary political, cultural, economic and social changes and reclassifications, modern higher education and teacher education – not only in Europe but in Africa and elsewhere – suggest new aims and targets. These aims are to find new ways of knowledge communication and production. Educational policies in Europe – like the Bologna Declaration and the Uniformization of Higher Education provide some ‘lessons’ for Higher Education and Teacher Education in Africa.

Over the past 65 years, Sub-Saharan Africa has been the terrain of the biggest education expansion drive in human history (Wolhuter & Van Niekerk, 2009). On top of this expansion, Africa has been the site of imaginative experiments and innovations in education (Samoff & Carrol, 2013, p. 403). These all seem to offer attractive and fertile ground for Comparative and International Education scholarship to flourish. This chapter surveys the historical development and current presence of various facets of the scholarly field of Comparative and International Education in Sub-Saharan Africa. The ultimate aim is to chart a future course for the field in the context of the meteoric rise (economically, demographically, and politically) of the continent. To commence with, an overview of this context is first given. Subsequently the history of formal education and then of higher education in the region are sketched. The evolution and current state of Comparative and International Education within this context is then surveyed, concluding with a reflection on its future prospects and course.

The aim of the present study is to investigate the mechanical behaviour of cross‐ply laminates under static tensile and buckling loading. Different cross‐ply laminates constituting of carbon fibers (CFRP), hybrid fibers (HFRP) and glass fibers (GFRP) in an epoxy matrix were considered. This work is also interested in identifying and characterizing the local damage in the composites with the use of acoustic emission method (AE).

The cross‐ply laminates are differentiated by the stacking sequences, thickness of 90° oriented layers and reinforcement. They are subjected to the static tensile and buckling load. The damage investigation is reached by the analysis of acoustic emission signals collected from static buckling tests.

The results show the effects of reinforcement type, stacking sequences and thicknesses ratio of 90° and 0° layers on the stiffness, failure load and displacement. A cluster analysis of acoustic emission data is achieved and the results are correlated to the damage mechanism of specimens under buckling tests.

The analysis of acoustic emission signals collected from static buckling tests under loading levels of 40, 60 and 100 per cent of the static failure load allows the damage investigation in cross‐ply laminates.

The way and manner in which energy is produced is known to have a significant impact on emissions. For this reason, the UK government has sought to enhance the efficiency of energy production/conversion by focusing on a number of energy production approaches, including Combined Heat and Power (CHP). The purpose of this paper is to describe a practical approach for assessing the feasibility of CHP.

The authors provide an overview of Combined Heat and Power (CHP); describe a new and easy‐to‐implement feasibility and optimisation model to aid in the installation of CHP; and discuss the practical feasibility issues of CHP through an analysis of existing case studies using the proposed model. The modelling utilises regression models which are created using historical data obtained from public sources.

Compared against alternatives, the model is shown to be particularly useful, as its functionality is embedded in resource‐intensive prime mover specifications obtained from seven real industrial cases.

The need for such a practical and easy‐to‐use model is driven by the existence of numerous models, which are mainly complex and not necessarily “user‐friendly”. The proposed model is set to provide a practical and user‐friendly model for CHP appraisal that is easy to understand and assess in terms of prime movers such as capital cost, payback, annual financial and CO₂ savings.

This chapter presents the development of Comparative Education in the most representative countries for this discipline in Western Europe, taking into account the diachronic evolution (since the first texts of Jullien de Paris in 1718 or the written work of Sadler in 1900) and the synchronicity of the discipline from which our patterns of committed intellectual activism have been perceived and have consequently allowed the regulation of its current mapping.

Special reference will be given to some of the classic and renewed dilemmas that have prevailed over the decades as cross-cutting themes of interest for specialists in Comparative Education with issues related to denomination, its purposes of ideographic or nomothetic nature, its sometimes problematic entailment with International Education, the significance of the lending and transferring policies in the current scenarios or the present increasing globalization phenomenon in our educational reality, among others.

The chapter also aims at recognizing the possibilities and, at the same time, the limitations currently faced by “Comparative Educations” in Cowen´s words, through working effectively with the most idiosyncratic signs of identity in the discourse and its most immediate future projection in the coming years.

We focus our article on the reasons that support the importance of the discipline: the global evolution of the current supranational scenarios from a social, economic or cultural perspective; the state of education since the contribution of educational policies or the situation of higher education in the context of the European Higher Education Area (EHEA) that, among other aspects, mark the good stage through which the analyzed discipline is experiencing.

Finally, the ratification of this statement is complemented by the firm consolidation of Comparative Education in the European context, giving reference not only to the articulation of its own associations or societies created but also to the journals emerged from them, with a notable impact on the rest of the world and their special contribution to the dissemination of the purposes of the discipline related to the generation and diffusion of policies and practices from a comparative view.

Mobile robots may perform very critical tasks under difficult operating conditions. Faults encountered during their tasks may cause the task to be interrupted or failed completely. In the active fault tolerant control methods, it is very important not only to detect the faults that occur in the robot, but also to isolate these faults to develop a fault recovery strategy that is suitable for that specific type of fault. This study aims to develop a model-based fault detection and isolation method for wheel slippage and motor performance degradation that may occur in wheeled mobile robots.

In the proposed method, wheel speeds can be estimated via the dynamic model of the mobile robot, which includes a friction model between the wheel and the ground. Four residual signals are obtained from the differences between the estimated states and the measured states of the mobile robot. Mobile robot’s faults are detected by using these signals. Also, two different residual signals are generated from the calculation of the traction forces with two different procedures. These six residual signals are then used to isolate possible wheel slippage and performance degradation in a motor.

The proposed method for diagnosing wheel slip and performance degradation in motors are tested by moving the robot in various directions. According to the data obtained from the test results, a logic table is created to isolate these two faults from each other. Thanks to the created logic table, slippage in any wheel and performance degradation in any motor can be detected and isolated.

Two different recovery strategies are needed to recover temporary wheel slippage and permanent motor faults. Therefore, it is important to isolate these two faults that create similar symptoms in robot’s general movement. Thanks to the method proposed in this study, it is not only possible to isolate the slipping wheel with respect to the non-slipping wheels or to isolate the faulty motor from the non-faulty ones, but also to isolate these two different fault types from each other.

This chapter commences by depicting the rise of Africa as a force on the world map as a contextual background for a survey of the education expansion and reform project on the continent in the past 65 years – arguably the biggest education expansion drive in human history. The main lines of the education expansion and education reform in Africa are reconstructed. Education in Africa is then assessed in terms of three dimensions: quantitative, qualitative, and equalization. While being nothing short of spectacular, the education project in Africa faces severe challenges, on all three fronts of the quantitative expansion, quality, and equality dimensions. At the same time, as the African continent is embracing the world of the twenty-first century, this changed world is also adding its share of imperatives to education. Finally, the role of comparative international scholarship in negotiating these imperatives and challenges is noted.